| 1. |
- Barth, Henrik, et al.
(author)
-
A cross-linked hyaluronic acid hydrogel (Healaflow(®)) as a novel vitreous substitute
- 2016
-
In: Graefe's Archives for Clinical and Experimental Ophthalmology. - : Springer. - 0721-832X .- 1435-702X. ; 254:4, s. 697-703
-
Journal article (peer-reviewed)abstract
- Purpose: Vitrectomy requires the substitution of the natural vitreous, as well as tamponading of retinal breaks. Clinically available alternatives such as gas and silicone oil have side effects such as inflammation, secondary glaucoma, cataract, and a need for head posturing. In this study, a hydrogel of cross-linked sodium hyaluronic acid (Healaflow(®)) is evaluated for use as a novel vitreous substitute.Methods: A combined 25-20-gauge pars plana vitrectomy with posterior vitreous detachment was performed in the right eye of twelve pigmented rabbits, with subsequent injection of approximately 1 ml Healaflow(®). Clinical evaluation, measurement of intraocular pressure (IOP), and full-field ERG were performed postoperatively. The rabbits were sacrificed at different time-points between 42 and 105 days. After enucleation, the eyes were examined macroscopically, photographed, and prepared for histological examination with routine microscopy and immunohistochemistry.Results: Healaflow(®) was successfully used with standard surgical procedures and remained translucent but did lose most of its viscosity during the postoperative period. One rabbit was lost due to unrelated causes. In two eyes iatrogenic partial retinal detachments were seen, and in two eyes significant cataract developed due to intra-operative complications. ERG-recordings revealed no toxic effect on rod or cone function. Routine microscopy and immunohistochemistry demonstrated normal morphology with some Müller cell activation (up-regulation of glial acidic fibrillary protein, GFAP) compared to unoperated eyes and no significant DNA-fragmentation (TUNEL-assay).Conclusions: Healaflow® did not affect retinal morphology or function negatively during long-term use as a vitreous substitute, making it highly interesting in this setting. An estimated retention time of a few weeks suggests potential for use as a short-term tamponade. Future work will include an increased ratio of cross-linking to prolong the structural integrity of the gel.
|
|
| 2. |
- Barth, Henrik, et al.
(author)
-
A new model for in vitro testing of vitreous substitute candidates
- 2014
-
In: Graefe's Archives for Clinical and Experimental Ophthalmology. - Hedidelberg, Germany : Springer. - 0721-832X .- 1435-702X. ; 252:10, s. 1581-1592
-
Journal article (peer-reviewed)abstract
- Purpose: To describe a new model for in vitro assessment of novel vitreous substitute candidates.Methods: The biological impact of three vitreous substitute candidates was explored in a retinal explant culture model; a polyalkylimide hydrogel (Bio-Alcamid (R)), a two component hydrogel of 20 wt.% poly (ethylene glycol) in phosphate buffered saline (PEG) and a cross-linked sodium hyaluronic acid hydrogel (Healaflow (R)). The gels where applied to explanted adult rat retinas and then kept in culture for 2, 5 and 10 days. Gel-exposed explants were compared with explants incubated under standard tissue culture conditions. Cryosections of the specimens were stained with hematoxylin and eosin, immunohistochemical markers (GFAP, Vimentin, Neurofilament 160, PKC, Rhodopsin) and TUNEL.Results: Explants kept under standard conditions as well as PEG-exposed explants displayed disruption of retinal layers with moderate pyknosis of all neurons. They also displayed moderate labeling of apoptotic cells. Bio-Alcamid (R)-exposed explants displayed severe thinning and disruption of retinal layers with massive cell death. Healaflow (R)-treated explants displayed normal retinal lamination with significantly better preservation of retinal neurons compared with control specimens, and almost no signs of apoptosis. Retinas exposed to Healaflow (R) and retinas kept under standard conditions showed variable labeling of GFAP with generally low expression and some areas of upregulation. PEG-exposed retinas showed increased GFAP labeling and Bio-Alcamid (R)-exposed retinas showed sparse labeling of GFAP.Conclusions: Research into novel vitreous substitutes has important implications for both medical and surgical vitreoretinal disease. The in vitro model presented here provides a method of biocompatibility testing prior to more costly and cumbersome in vivo experiments. The explant culture system imposes reactions within the retina including disruption of layers, cell death and gliosis, and the progression of these reactions can be used for comparison of vitreous substitute candidates. Bio-Alcamid (R) had strong adverse effects on the retina which is consistent with results of prior in vivo trials. PEG gel elicits reactions similar to the control retinas whereas Healaflow (R) shows protection from culture-induced trauma indicating favorable biocompatibility.
|
|
| 3. |
- Barth, Henrik, et al.
(author)
-
A New Retinal Detachment Treatment Model for Evaluation of Vitreous Tamponades
- 2021
-
In: Current Eye Research. - : Taylor & Francis. - 0271-3683 .- 1460-2202. ; 46:3, s. 373-379
-
Journal article (peer-reviewed)abstract
- PURPOSE: To develop a treatment model of rhegmatogenous retinal detachment (RRD) in which the effects of various vitreous tamponades can be explored.METHODS: In a primary session, detachment was produced in the right eye of 24 rabbits using vitrectomy, posterior vitreous detachment, retinal break induction, and subretinal injection of viscoelastic solution. The following day, detachments were treated in 16 eyes using SF6 (n = 8) or Healaflow® (HF, a cross-linked hyaluronic acid hydrogel, n = 8) tamponade. Animals were followed for 1 month and thereafter examined macroscopically and morphologically in hematoxylin and eosin-stained sections.RESULTS: Retinal detachment (RD) was successfully treated using repeated surgery. Two HF eyes developed progressive vitritis and were excluded from further evaluation. Enlargement of the initial retinal rupture with concomitant RD was seen in 4/8 SF6 eyes, while all 6 HF eyes displayed an attached retina. Attached areas showed a normal retinal morphology except for in 1 HF eye with extensive degeneration.CONCLUSIONS: The RRD repeat vitrectomy model offers a possibility to explore the efficacy and complications of novel potential vitreous tamponades. Gel-based Healaflow® displays excellent anatomic reattachment, however, vitritis and retinal degeneration in some cases warrants further investigation.
|
|
| 4. |
|
|
| 5. |
|
|
| 6. |
- Barth, Henrik, et al.
(author)
-
Inflammatory responses after vitrectomy with vitreous substitutes in a rabbit model
- 2019
-
In: Graefe's Archives for Clinical and Experimental Ophthalmology. - : Springer. - 0721-832X .- 1435-702X. ; 257:4, s. 769-783
-
Journal article (peer-reviewed)abstract
- PURPOSE: To investigate the inflammatory response of current and future potential vitreous substitutes in an experimental in vivo vitrectomy model.METHODS: Twenty-five gauge pars plana vitrectomy was performed in the right eye of 60 pigmented rabbits, with subsequent injection of 0.5-1.0 ml of Healaflow® (cross-linked hyaluronic acid, n = 12), Bio-Alcamid® (polyalkylimide, n = 8), silicone oil (n = 12), or balanced saline solution (BSS, n = 28). Postoperative clinical evaluation was performed; and the rabbits were sacrificed at 1 day, 1 week, or 1 month. The eyecups were then examined macroscopically; the retinas sectioned and stained with hematoxylin and eosin (Htx), and immunohistochemically labeled for glial fibrillary acidic protein (GFAP), CD45, galectin-3, CD68, and CD20. Unoperated left eyes from treated animals as well as eyes from untreated animals were used as controls.RESULTS: Vitrectomy without major complications was achieved in 46/60 eyes. The remaining 14 eyes were analyzed separately. One eye developed endophthalmitis after 1 week and was excluded. Eyes treated with Healaflow®, silicone oil, and BSS had a comparable appearance macroscopically and in Htx-stained sections, whereas Bio-Alcamid®-injected eyes exhibited increased macroscopic inflammation and severely affected retinas. GFAP upregulation was present in all treatment groups, most prominent in eyes treated with Bio-Alcamid® and silicone oil. Upregulation of CD45 and CD68 in the inner retina and vitreous space was most prominent with Bio-Alcamid® treatment, and these eyes together with their silicone oil-treated counterparts also displayed a stronger upregulation of CD20-labeled cells compared with remaining groups. General upregulation of galectin-3, mainly in the inner retina, was found in all groups. In eyes with perioperative complications, labeling of CD45, CD68, and especially GFAP was comparably high.CONCLUSIONS: We here describe differences in the postsurgery inflammatory profiles of existing and potential vitreous substitutes. Bio-Alcamid® and silicone oil display severe signs of gliosis and inflammation, whereas Healaflow® elicits minimal reactions comparable with BSS, highlighting its potential application as a vitreous substitute in a future clinical setting.
|
|
| 7. |
- Bäckman, Anders, et al.
(author)
-
The efficiency of cross-linking methods in eradication of bacteria is influenced by the riboflavin concentration and the irradiation time of ultraviolet light
- 2014
-
In: Acta Ophthalmologica. - Hoboken, USA : John Wiley & Sons. - 1755-375X .- 1755-3768. ; 92:7, s. 656-661
-
Journal article (peer-reviewed)abstract
- Purpose: To determine bacterial eradication using numerous riboflavin concentrations and different ultraviolet light A (UVA) radiant and exposure time in an experimental model.Methods: Dilutions of Staphylococcus epidermidis were mixed with riboflavin at varying concentrations (0.007-0.09%). Effects on bacterial growth were evaluated after 0, 3, 6, 30 and 60min of UVA exposure (irradiance 30 and 3mW/cm(2)). Standard settings of UVA were compared with high-power UVA approach. Different fluid thicknesses of the exposed dilutions were also examined to improve the model.Results: Bacterial eradication (%) was increased after 60 compared with 30min of UVA exposure for concentrations of 0.03-0.07% but not for 0.09% riboflavin. There was a significant difference between the efficacy between 0.03 and 0.09% and eradication dropped from 80% to 50% (p=0.01). A correlation could be calculated for the amount of riboflavin at 60min of UVA and the ability to kill bacteria (p=0.01). The antibacterial effect was more pronounced when the tested bacterial suspension thickness was reduced. High-power UVA method was less potent in microbial elimination, eradicating only 60% of bacteria after 6min versus 97-99% after 60min in the low-power setting, compared with respective controls (p=0.02).Conclusions: In these in vitro experiments, a longer UVA exposure time in combination with lower riboflavin levels were found to be favourable in killing bacteria as compared to the standard cross-linking settings. Further studies are needed to evaluate the clinical relevance of these findings.
|
|
| 8. |
- Carlsson, Jan-Olof, et al.
(author)
-
Retinal surgery quality indicators for uncomplicated primary rhegmatogenous retinal detachment without a national registry
- 2022
-
In: Acta Ophthalmologica. - : Wiley-Blackwell Publishing Inc.. - 1755-375X .- 1755-3768. ; 100:8, s. e1589-e1594
-
Journal article (peer-reviewed)abstract
- PURPOSE: The objective of this study was to evaluate the possibility of analysing quality indicators for uncomplicated primary rhegmatogenous retinal detachment in a hospital department of ophthalmology without the support of a national registry or need to collect data from referring ophthalmological centres.METHODS: In 2014, we operated 231 consecutive eyes with uncomplicated retinal detachment. Our quality indicators were primary anatomical success, final anatomical success and postoperative endophthalmitis. We reviewed medical records in our university surgical department retrospectively and compared them with medical records from the regional hospitals that had referred most of the operated patients and done their own postoperative examination. Our hypothesis was that any retinal re-detachment and/or serious postoperative complication would be reported back.RESULTS: The medical records at the surgical department revealed primary anatomic success for 91.3% of eyes and final anatomical success of 99.6%. The data from the regional hospitals confirmed that our hypothesis was correct. All patients with adverse outcomes were referred back for reoperation. Patients who were not referred again had an attached retina and showed no signs of endophthalmitis.CONCLUSION: Our hypothesis that data in the surgical department's medical records would closely reflect those in referring hospitals was borne out. This supports, under current conditions, an effective strategy for analysing chosen quality indicators without relying on a national registry or reviewing records from regional hospitals.
|
|
| 9. |
|
|
| 10. |
- Crafoord, Sven, 1950-, et al.
(author)
-
Cellular migration into neural retina following implantation of melanin granules in the subretinal space
- 2000
-
In: Graefe's Archives for Clinical and Experimental Ophthalmology. - : Springer Science and Business Media LLC. - 0721-832X .- 1435-702X. ; 238:8, s. 682-689
-
Journal article (peer-reviewed)abstract
- Background: In some retinal diseases and following transplantation of retinal pigment epithelium (RPE), melanin granules are liberated to the subretinal space. Our aim was to investigate the cellular response to implanted extracellular melanin. Methods: After pars plana vitrectomy, 17 albino rabbits received a suspension of melanin granules in the subretinal space. Postoperative examination included ophthalmoscopy, color fundus photography, histology using monoclonal antibodies identifying RPE cells (AE1/3), macrophages (RAM 11), B-lymphocytes (CD20) and T-lymphocytes (CD45), and electron microscopy. The follow-up time was 2 weeks, 4 weeks and 6 months. Results: On fundus photographs, the layer of melanin showed focal attenuation with lighter areas at 6 months. Melanin granules were phagocytosed by RPE cells and macrophages at 2 weeks, as identified by monoclonal antibodies. In areas where an abundance of melanin was present, multilayers of macrophages were seen associated with considerable photoreceptor damage. Pigment-laden cells invaded the neural retina. The cellular infiltration of the retina was focal, and when it involved the outer nuclear layer the photoreceptor damage was severe. Electron microscopy demonstrated the presence of melanosomes intracellularly in Müller glia. The process of phagocytosis and removal of melanin granules from the subretinal space was slow and not completed at 6 months. Conclusion: Our experiments show that implantation of melanin granules in the subretinal space of albino rabbits may induce a considerable phagocytic cellular response featuring the host’s RPE, macrophages and glial cells. The migration of pigment-laden cells into the neural retina was associated with focal photoreceptor damage.
|
|
| 11. |
|
|
| 12. |
- Crafoord, Sven, 1950-, et al.
(author)
-
Cyclosporine treatment of RPE allografts in the rabbit subretinal space
- 2000
-
In: Acta Ophthalmologica Scandinavica. - : Wiley. - 1395-3907 .- 1600-0420. ; 78:2, s. 122-129
-
Journal article (peer-reviewed)abstract
- Purpose: To determine the effects of systemic cyclosporine A (CsA) on the survival of retinal pigment epithelial (RPE) allografts in the subretinal space in an animal model using atraumatic transplantation surgery.Methods: Following pars plana vitrectomy, an RPE cell suspension from brown rabbits was injected with a glass micropipette into the subretinal space of 39 albino rabbits. For immunosuppression, 22 rabbits were given an injection of CsA, 20 mg daily intramuscularly, 17 rabbits with RPE grafts were controls. The grafts were monitored by biomicroscopy, color fundus photography, and fluorescein angiography. Rabbits were sacrificed at 1, 3 and 6 months, respectively, and the eyes processed for light and electron microscopy including immunohistochemistry.Results: After three months, the transplanted RPE cells, in both the CsA group and the controls, formed a monolayer in the subretinal space. Although a few macrophages were encountered, there was no massive cellular infiltration and the photoreceptor layer was well preserved. After six months, however, there was a disruption of grafted RPE cells in both groups, characterized by dispersion of melanin pigment in the subretinal space, and invasion of macrophages with focal photoreceptor damage but no infiltration of lymphocytes in the retina or choroid. No significant differences between the CsA treated and the control eyes were discernible.Conclusion: Although the subretinal space has been considered an immunologically privileged site, we found that the survival of RPE allografts was limited. CsA did not prevent RPE allograft destruction in the subretinal space. The transplant seems to be disrupted either by immunological mechanisms that are not inhibited by CsA, or by nonimmunologic events.
|
|
| 13. |
|
|
| 14. |
- Crafoord, Sven, 1950-, et al.
(author)
-
Experimental transplantation of autologous iris pigment epithelial cells to the subretinal space
- 2001
-
In: Acta Ophthalmologica Scandinavica. - : Wiley. - 1395-3907 .- 1600-0420. ; 79:5, s. 509-514
-
Journal article (peer-reviewed)abstract
- Purpose: To investigate the cellular morphology in the subretinal space following transplantation of iris pigment epithelial (IPE) cells from the same eye. Methods: Following an iridectomy, fresh IPE cells were prepared and no culturing performed. After pars plana vitrectomy, a suspension of autologous IPE cells was injected into the subretinal space in 37 rabbits. The grafts were monitored by ophthalmoscopy and colour fundus photography. Rabbits were sacrificed at 1, 2, 3 and 6 months, respectively, and the eyes examined with light and electron microscopy. Results: The grafted area retained the same configuration over 6 months but then appeared less pigmented. At 1-3 months, the IPE formed one or more contiguous layers on top of native RPE. At 6 months, cells compatible with grafted IPE were present in the subretinal space, often forming monolayer-like chains integrating with the native RPE. Depigmented cells of presumed IPE origin were seen and frequently in association with abundant melanin granules located in the apical portion of adjacent RPE cells. In such areas, large macrophage-like cells were observed. Conclusion: Transplanted IPE cells survived for up to 6 months in the subretinal space. Our observations suggest a scenario of remodelling of the cellular layers in the subretinal space over time where grafted IPE cells formed a compound layer with the native RPE. Transplantation of autologous IPE cells may have a potential as a treatment modality in selected cases of age-related macular degeneration.
|
|
| 15. |
- Crafoord, Sven, 1950-
(author)
-
Experimental transplantation of retinal and iris pigment epithelial cells into the subretinal space
- 2000
-
Doctoral thesis (other academic/artistic)abstract
- A dysfunction of the retinal pigment epithelium (RPE) is the main cause for the development of age-related macular degeneration (ARMD) and visual loss in elderly people. For about 10 years experimental and clinical attempts to transplant RPE cells have been performed. The aims of this study were to elucidate the long term results of RPE allografts, to develop an atraumatic transplantation technique, and to explore the cellular response to RPE allografts, melanin granules, and autologous IPE cells.Surgery was performed on rabbits with a follow-up period of up to six months. After a pars plan vitrectomy, a subretinal bleb was created into which a suspension of RPE/IPE donor cells or melanin granules was injected. Pigmented RPE donor cells or preparations of melanin granules were implanted subretinally in albino rabbits. Pigmented rabbits were used in IPE transplantation. The eyes were monitored with ophthalmoscopy, fundus photography, light microscopy, electron microscopy and immunohistochemistry.Transplantation of suspensions of fresh pigmented RPE cells to the subretinal space in rabbits is feasible and induces virtually no complications when an atraumatic surgical procedure is used. The allograft forms a monolayer in conjunction with the native RPE and persists almost intact up to three months. At six months after transplantation, there was a cellular response exhibiting multilayers of cells, such as RPE and macrophages. Damage to adjacent photoreceptors in combination with melanin granules in the subretinal space indicates graft failure. No infiltration of lymphocytes was seen. Whether the cellular response was due to immunological or non-immunological mechanisms could not be determined from this experiment.Cyclosporine (CsA) could not prevent disintegration of the RPE transplant and graft failure. CsA was not capable of promoting graft survival as compared to the controls. The transplant seems to be disrupted either by immunological mechanisms that are not inhibited by CsA, or by non-immunologic events.Implantation of melanin granules to the subretinal space of albino rabbits induces a considerable phagocytic cellular response involving the host’s RPE, macrophages and glial cells. The migration of pigment-laden cells into the neural retina was frequently associated with focal photoreceptor damage. The cellular response was identical to that ensuing RPE cell transplantation. These findings support the concept that non-immunological events have a considerable influence on the outcome.In order to evaluate the impact of non-immunological mechanisms, a technique of transplanting fresh autologous IPE cells to the subretinal space of the same eye was developed. Grafted IPE cells were seen to survive for six months. There was a remodeling of the compound cellular layers in the subretinal space over time where grafted IPE cells joined the native RPE cells. The cellular response that developed exhibited macrophages, but no lymphocytes, and was in this respect similar to that observed following RPE transplantation.In RPE allografts, the photoreceptors appeared normal on light microscopy at three months, but at six months, the photoreceptors overlying the transplants generally exhibited pathological changes. In autologous IPE grafts, on the other hand, the photoreceptors displayed normal outer segment length and outer nuclear layer on top of grafted IPE cells. Focally, multilayers of both grafted IPE and RPE cells, together with macrophages, induce damage to adjacent photoreceptors as observed at 6 months. Cellular multilayers in the subretinal space, irrespective of genesis, are likely to have adverse effects on photoreceptors. The experiments using autologous IPE grafts show that non-immunogenic mechanisms have a decisive impact on the outcome of the transplant in the subretinal space.
|
|
| 16. |
|
|
| 17. |
- Crafoord, Sven, et al.
(author)
-
Experimental vitreous tamponade using polyalkylimide hydrogel
- 2011
-
In: Graefe's Archives for Clinical and Experimental Ophthalmology. - : Springer Science and Business Media LLC. - 0721-832X .- 1435-702X. ; 249:8, s. 1167-74
-
Journal article (peer-reviewed)abstract
- PURPOSE: To evaluate polyalkylimide as a possible vitreous tamponading agent.METHODS: A 20-gauge pars plana vitrectomy and posterior vitreous detachment were performed in the right eye of six pigmented rabbits. Approximately 1 ml of viscoelastic gel, polyalkylimide (Bio-Alcamid) was thereafter injected into the vitreous space. Full-field ERG and intraocular pressure (IOP, Tonopen) was measured pre-and postoperatively at regular intervals up to 28 days. At day 6 or 28, the rabbits were sacrificed and the eyes were examined macroscopically, photographed, and prepared for histological examination with routine microscopy.RESULTS: The viscoelastic hydrogel was successfully injected, and remained translucent with preserved gel properties throughout the postoperative period. The postoperative IOP was unchanged compared to preoperative values. Five of six eyes displayed retinal edema or pigmentary changes centrally while the periphery appeared intact. ERG recordings showed a radical decrease in rod- and cone-derived B-wave amplitudes. Histological examination confirmed varying degrees of edema combined with neuronal cell death within the retinal layers in the central part of the fundus, while the peripheral part appeared intact.CONCLUSION: Polyalkylimide displays favourable physical properties when used as a vitreous tamponade. However, the hydrogel causes functional and morphological retinal damage when in direct contact with the inner retina. Possible pathological mechanisms include osmotic imbalance and direct toxic effects, and modification of biochemical properties is warranted before clinical use will be possible.
|
|
| 18. |
- Crafoord, Sven, 1950-, et al.
(author)
-
Long-term outcome of RPE allografts to the subretinal space of rabbits
- 1999
-
In: Acta Ophthalmologica Scandinavica. - : Wiley. - 1395-3907 .- 1600-0420. ; 77:3, s. 247-254
-
Journal article (peer-reviewed)abstract
- Purpose: To determine the long-term RPE allograft survival in the subretinal space using suspensions of RPE cells and atraurnatic transplantation surgery.Methods: Nineteen albino rabbits were transplanted with suspensions of pigmented RPE cells from brown rabbits. Following pars plana vitrectomy, the RPE cell suspension was injected through a small retinotomy using a glass micropipette into the subretinal space under microscopic control. No immunosuppression was used. The eyes were monitored by biomicroscopy, color fundus photography, and fluorescein angiography. Rabbits were sacrificed at 1, 3 and 6 months, respectively, and the eyes processed for light and electron microscopy, using monoclonal antibodies for identifying macrophages.Results: Transplanted RPE cells were present in the subretinal space in all eyes at 6 months. There was no fluorescein leakage. Generally, the RPE allograft formed a monolayer, but focal fragmentation and disruption with dispersion of melanin pigment occurred. Foci of multilayers of cells in the subretinal space, containing large macrophages, were associated with adjacent photoreceptor damage. There was no infiltration of lymphocytes but macrophages and glial cells were contiguous to the transplant. Cells harboring intracytoplasmatic melanin pigment were observed in the neural retina.Conclusion: Transplantation of RPE cell suspensions to the subretinal space generally forms a monolayer that persists at 6 months, However, in areas of multilayers of RPE cells and macrophages, graft failure occurs in combination with adjacent photoreceptor damage. Graft failure is not associated with the infiltration of lymphocytes, but other mechanisms seem to occur.
|
|
| 19. |
- Crafoord, Sven, 1950-, et al.
(author)
-
Photoreceptor survival in transplantation of autologous iris pigment epithelial cells to the subretinal space
- 2002
-
In: Acta Ophthalmologica Scandinavica. - : Wiley. - 1395-3907 .- 1600-0420. ; 80:4, s. 387-394
-
Journal article (peer-reviewed)abstract
- Purpose: To investigate photoreceptor survival in transplantation of non-cultured iris pigment epithelial (IPE) cells to the subretinal space in a prospective experimental study. Methods: Upper iridectomies were carried out in the right eyes of 37 pigmented rabbits. Suspensions of freshly harvested autologous IPE cells (without culturing) were prepared and injected into the subretinal space of the same eye. Follow-up examinations were carried out using ophthalmoscopy and colour fundus photography. The rabbits were killed at 1, 2, 3 and 6 months, respectively, and the eyes examined with light and electron microscopy. Results: On histological examination, the photoreceptor cells were found to be well-preserved in grafted areas at 1-3 months. At 6 months, the photoreceptors generally disclosed a normal nuclear layer and long outer segments when overlying areas with single cells or clusters of transplanted IPE cells. Multilayers of cells in abundance, including native RPE cells and macrophages (stained with RAM 11), particularly under microfolds of the neural retina, were occasionally associated with photoreceptor damage and nuclear drop out from the outer retinal layer. There was no inflammatory response in the choroid and the choriocapillaris remained patent. Conclusion: The experiments show that grafting freshly harvested autologous IPE cells to the subretinal space is feasible and that the photoreceptors generally survive for at least 6 months when overlying the transplanted areas. Multi-layers of abundant cells in the subretinal space may induce adverse focal effects on adjacent photoreceptors.
|
|
| 20. |
- Crafoord, Sven, et al.
(author)
-
Sheathotomy in complicated cases of branch retinal vein occlusion
- 2008
-
In: Acta Ophthalmologica. - : Wiley. - 1755-3768 .- 1755-375X. ; 86:2, s. 146-150
-
Journal article (peer-reviewed)abstract
- Purpose: To report the clinical experience and results of using a microsurgical technique to decompress the arteriovenous connection in complicated branch retinal vein occlusion (BRVO) combined with haemorrhage, oedema and ischaemia.Methods: We carried out a retrospective, non-randomized, interventional case study of the surgical sheathotomy decompression procedure. We enrolled 12 patients (seven women, five men; median age 64 years) with BRVO and decreased visual acuity (VA) caused by haemorrhage, oedema and ischaemia. The mean duration of thrombosis was 7 months (2–15 months). The patients were examined for pre- and postoperative best corrected VA (BCVA), intraocular pressure (IOP) and fundus photography. Ten patients were examined with fluorescein angiography and eight with ocular coherence tomography (OCT). Postoperative progression of cataract was recorded, as were other complications. The mean follow-up time was 20 months (8–39 months).Results: Best corrected VA had improved in nine patients, was unchanged in one patient and had deteriorated in two patients at the last follow-up. Noted complications were venous haemorrhage at surgery in five patients, retinal detachment in one patient and progression of cataract in four patients.Conclusions: Microsurgical treatment with sheathotomy of BRVO is a technically feasible procedure with few complications. Postoperative increased reperfusion could explain the resolution of macular haemorrhage, oedema and ischaemia, and may improve visual function in patients with this common vascular eye disease.
|
|
| 21. |
- Crafoord, Sven, et al.
(author)
-
Transplantation of Autologous Iris Pigment Epithelial Cells To the Subretinal Space : II. Photoreceptor Survival and Consequences of Cellular Multilayers
-
Other publication (other academic/artistic)abstract
- Purpose: To study the effects of transplanted iris pigment epithelial (IPE) cells in the subretinal space on the survival of adjacent photoreceptors.Methods: An upper iridectomy was made on the right eye of 37 pigmented rabbits. Suspensions of autologous IPE cells were prepared and injected into the subretinal space of the same eye. Follow- up examinations was performed using ophthalmoscopy and calor fundus photography. At 1, 2, 3 and 6 months, respectively, the rabbits were sacrificed and the eyes examined with light and electron microscopy.Results: On histological examination, the photoreceptor cells were well preserved in grafted areas at 1-3 months. At 6 months, also, the photoreceptors generally disclosed a normal nuclear layer and long outer segments when overlying areas with single cells or clusters of IPE. However, multilayers of transplanted I PE, native RPE cells and macrophages in the subretinal space were frequently associated with photoreceptor damage and nuclear drop out from the outer retinal layer.Conclusion: In this experimental model, the photoreceptors generally survive adjacent to grafted IPE cells for 6 months. Multilayers of subretinal cells are likely to induce adverse effects on adjacent photoreceptors which is a new finding that requires further investigation.
|
|
| 22. |
- Crafoord, Sven, et al.
(author)
-
Transplantation of Autologous Iris Pigment Epithelial Cells to the Subretinal Space : I. Morphological Features
-
Other publication (other academic/artistic)abstract
- Purpose: To investigate the cellular morphology in the subretinal space following transplantation of iris pigment epithelial (IPE) cells from the same eye.Methods: Following an iridectomy, fresh IPE cells were prepared. After pars plana vitrectomy, a suspension of autologous IPE cells was injected into the subretinal space in 37 rabbits. The grafts were monitored by ophthalmoscopy and calor fundus photography. Rabbits were sacrificed at 1, 2, 3 and 6 months, respectively, and the eyes examined with light and electron microscopy.Results: The grafted area retained the same configuration over 6 months but then appeared less pigmented. At 1-3 months, the IPE formed one or more contiguous layers on top of native RPE. At 6 months, cells compatible with grafted IPE were present in the subretinal space forming mono-layer like chains integrating with the native RPE. Depigmented cells of presumed IPE origin were seen. lt was commonly observed that the apical portion of RPE cells disclosed abundant melanin granules. With time the grafted cells appeared to decrease in number but focal clusters of IPE cells and large macrophages were present.Conclusion: Transplanted IPE cells survived for up to 6 months in the subretinal space. Our observations suggest a scenario of remodeling of the cellular layers in the subretinal space over time where grafted IPE cells formed a compound layer with the native RPE. Transplantation of autologous IPE cells may have a potential as a treatment modality in selected cases of age-related macular degeneration with impending degeneration of RPE and choriocapillaris.
|
|
| 23. |
|
|
| 24. |
- Dabrowska-Kloda, Kinga, et al.
(author)
-
DMEK Surgery at a Tertiary Hospital in Sweden. Results and Complication Risks
- 2024
-
In: Clinical Ophthalmology. - : Dove Medical Press. - 1177-5467 .- 1177-5483. ; 18, s. 1841-1849
-
Journal article (peer-reviewed)abstract
- PURPOSE: This study reports clinical outcomes up to 6 years after Descemet's membrane endothelial keratoplasty (DMEK) performed at the Department of Ophthalmology, Örebro University Hospital, Örebro, Sweden.METHODS: The study has a cross-sectional and case series design. Inclusion criteria were all DMEK-operated eyes during 2013-2018 until repeat keratoplasty.RESULTS: Altogether 162 eyes from 120 patients were enrolled. Among eyes without preoperative comorbidities, examined 1-6 years after DMEK, 85.8% achieved visual acuity of 0.1 logMAR or better. The median endothelial cell density (ECD) loss was 27% in a cohort of eyes examined 1-2 years post-DMEK, 31% at 2-3 years, 42% at 3-4 years, and > 60% at 4-6 years post-DMEK. ECD at the examination timepoint was correlated with donor ECD (as expected) and time since surgery.CONCLUSION: The results from DMEK surgeries in Örebro, Sweden, are promising. Further studies with even longer follow-up are needed to evaluate graft sustainability.
|
|
| 25. |
- Gili, Nasser J., et al.
(author)
-
Preoperative preparation of eye with chlorhexidine solution significantly reduces bacterial load prior to 23-gauge vitrectomy in Swedish health care
- 2018
-
In: BMC Ophthalmology. - : BioMed Central (BMC). - 1471-2415. ; 18
-
Journal article (peer-reviewed)abstract
- Background: Bacteria in the conjunctiva present a potential risk of vitreous cavity infection during 23-gauge pars plana vitrectomy (PPV). Current preoperative procedures used in Sweden include irrigation with chlorhexidine solution (CHX) 0.05% only and no iodine solutions. We evaluated the bacterial diversity and load before and after this single antibacterial measure.Methods: In a prospective, consecutive cohort we investigated bacterial growth in samples from 40 eyes in 39 consecutive individuals subjected to vitrectomy. A conjunctival specimen was collected from each preoperative patient before and after irrigating of eye with CHX, 0.05% solution. Iodine was not used during any part of the surgery. One drop of chloramphenicol was administered prior to surgery. Samples from vitreous cavity were collected at the beginning and end of vitrectomy. All conjunctival specimens were cultured for different species and quantified using colony forming units (CFU).Results: There was a significant 82% reduction in the total number of CFUs for all bacteria in all eyes (P < 0.0001), and 90% reduction for coagulase negative staphylococci (CoNS) alone (P = 0.0002). The number of eyes with positive bacterial growth in conjunctival samples decreased from 33 to 18 after irrigation with CHX (P = 0.0023). The most common bacteria prior to surgery were CoNS (70%), Propionibacterium acnes (55%) and Corynebacterium species (36%). No case of post-vitrectomy endophthalmitis was reported during mean follow-up time, which was 4.6 +/- 2.3 (range; 1.5 to 9) months.Conclusions: Patients undergoing PPV harbored bacteria in conjunctiva capable of causing post-vitrectomy endophthalmitis. Preoperative preparation with CHX significantly reduced the bacterial load in the conjunctival samples subsequently leading to very low inoculation rates in recovered vitreous samples. Thus, CHX used as a single disinfectant agent might be an effective preoperative procedure for eye surgery in Sweden. This is a relatively small study but the results could be a reference for other intraocular surgeries.
|
|
| 26. |
- Gupta, Anil, et al.
(author)
-
Postoperative pain after abdominal hysterectomy : A double-blind comparison between placebo and local anesthetic infused intraperitoneally
- 2004
-
In: Anesthesia and Analgesia. - 0003-2999 .- 1526-7598. ; 99:4, s. 1173-1179
-
Journal article (peer-reviewed)abstract
- Abdominal hysterectomy is associated with moderate to severe postoperative pain. We randomly divided 40 patients (ASA status I-II) undergoing elective abdominal hysterectomy into 2 groups: group P received an infusion of normal saline 5 mL/h via a catheter placed intraperitoneally at the end of surgery, and group L received 0.25% levobupivacaine 12.5 mg/h (5 mL/h). Ketobemidone was administered IV via a patient-controlled analgesia pump as a rescue analgesic in all patients. The catheter was removed after 24 h. Incisional pain, deep pain, and pain on coughing were assessed 1, 2, 3, 4, 8, 16, and 24 h after surgery by using a visual analog scale. Ketobemidone consumption during 0-72 h was recorded. Time to sit, walk, eat, and drink; home discharge; and plasma concentrations of levobupivacaine were also determined. Pain at the incision site, deep pain, and pain on coughing were all significantly less in group L compared with group P at 1-2 h after surgery. After 4 h, the mean visual analog scale pain scores at rest and during coughing remained <3 cm during most time periods. Total ketobemidone consumption during 4-24 h was significantly less in group L compared with group P (mean, 19 versus 31 mg, respectively). A less frequent incidence of postoperative nausea, but not vomiting, was also found during 4-24 h in group L compared with group P (P < 0.025). Total and free plasma concentrations of levobupivacaine were small. We conclude that levobupivacaine used as an infusion intraperitoneally after elective abdominal hysterectomy has significant opioid-sparing effects.
|
|
| 27. |
- Joussen, Antonia M, et al.
(author)
-
Heavy silicone oil versus standard silicone oil in as vitreous tamponade in inferior PVR (HSO Study) : interim analysis
- 2011
-
In: Acta Ophthalmologica. - : Wiley. - 1755-375X .- 1755-3768. ; 89:6, s. e483-e489
-
Journal article (peer-reviewed)abstract
- PURPOSE: The Heavy Silicone Oil versus Standard Silicone Oil Study (HSO study) is designed to answer the question whether a heavier-than-water tamponade improves the prognosis of eyes with proliferative vitreoretinopathy (PVR) of the lower retina.METHODS: The HSO Study is a multicentre, randomized, prospective, controlled clinical trial stratified by surgeon comparing two endotamponades within a two-arm parallel-group design. Patients with inferiorly and posteriorly located PVR grade C-A6 were randomized to either HSO or standard silicone oil as a tamponading agent. The main end-point criteria are complete retinal attachment at 12 months and change in visual acuity (VA) 12 months postoperatively compared to the preoperative VA.RESULTS: Forty-six patients treated with HSO were compared to 47 patients treated with standard silicone oil. There was no difference among the groups regarding baseline data. Three patients in the HSO and five patients in the standard silicone oil group fulfilled intraoperative exclusion criteria. There was no significant difference between both groups regarding anatomical success. Neither noninferiority nor superiority was shown with regard to final acuity.CONCLUSIONS: The HSO Study is the first randomized prospective clinical trial to compare heavy and standard silicone oil in patients with PVR of the lower retina. The intermediate results failed to demonstrate superiority of a heavy tamponade.
|
|
| 28. |
- Landström, Fredrik J, et al.
(author)
-
Electroporation therapy of skin cancer in the head and neck area.
- 2010
-
In: Dermatologic Surgery. - : Ovid Technologies (Wolters Kluwer Health). - 1076-0512 .- 1524-4725. ; 36:8, s. 1245-50
-
Journal article (peer-reviewed)abstract
- BACKGROUND: Electroporation therapy is a new cancer treatment modality in which a locally applied electrical field enhances cell membrane permeability, allowing greater intracellular accumulation of a chemotherapeutic agent.OBJECTIVE: To evaluate the efficacy of electroporation therapy in treating basal cell and squamous cell carcinomas of the skin.MATERIALS AND METHODS: Six patients with skin cancer of the head and neck were treated using electroporation therapy with intratumorally injected bleomycin. Orbital growth, facial nerve proximity, or proximity to cartilage of the external meatus complicated four of these tumors. The intention was curative. The follow-up period was 24 months and included biopsies after 8 weeks.RESULTS: In four of the six patients, one treatment was enough to eradicate the tumor. In one patient, the tumor persisted even after a second treatment with electroporation therapy. A septal cartilage perforation was the only major complication. The cosmetic results were very satisfactory. One additional recurrence was recorded 6 months after the follow-up periodCONCLUSION: Electroporation therapy is a promising new cancer treatment that should be further evaluated as an alternative to surgery, especially in complicated skin cancer.
|
|
| 29. |
- Makdoumi, Karim, 1977-, et al.
(author)
-
A prospective long-term follow-up study of optic disc pit maculopathy treated with pars plana vitrectomy, drainage of subretinal fluid and peeling of internal limiting membrane
- 2020
-
In: Acta Ophthalmologica. - : Wiley-Blackwell. - 1755-375X .- 1755-3768. ; 98:8, s. 822-827
-
Journal article (peer-reviewed)abstract
- PURPOSE: To describe the long-term results of surgical repair of patients with optic disc pit maculopathy (ODP-M).METHODS: Prospective, consecutive, noncomparative follow-up study including 12 patients with ODP-M treated by pars plana vitrectomy (PPV), peeling of internal limiting membrane followed by gas tamponade. Subretinal fluid (SRF) was drained in 11 eyes through a retinotomy without laser photocoagulation. Preoperatively, macular detachment with retinoschisis was seen in 9 out of 12 eyes with three eyes having only subretinal fluid in the macular area. The median age at surgery was 20 years (range 9-60 years).RESULTS: Follow-up time from initial surgery was 63 months (median). Eight eyes were anatomically reattached after one operation without remaining SRF in the macula. Two patients required a reoperation due to leakage from the retinotomy and another two underwent a second PPV procedure due to late recurrences. Successful healing was at follow-up control observed in 11 of 12 eyes. There was no statistically significant difference in visual acuity between patients before and after surgery (p = 0.24). Central visual field defects with depressed mean deviation were detected in all treated eyes.CONCLUSION: In this long-term study of ODP-M final outcome regarding healing was relatively efficacious, however, a relatively large proportion had complications associated to retinotomies. We conclude that drainage of SRF should likely be avoided since it appears to contribute little to the resorption rate of SRF and seems to linked to unnecessary risks.
|
|
| 30. |
- Makdoumi, Karim, 1977-, et al.
(author)
-
Comparison of UVA- and UVA/riboflavin-induced growth inhibition of Acanthamoeba Castellanii
- 2013
-
In: Graefe's Archives for Clinical and Experimental Ophthalmology. - New York, USA : Springer. - 0721-832X .- 1435-702X. ; 251:2, s. 509-514
-
Journal article (peer-reviewed)abstract
- Purpose To investigate whether ultraviolet light (UVA) at 365 nm can inhibit/eliminate Acanthamoeba growth and if riboflavin would potentiate such an association.Method: Acanthamoeba castellanii in a fluid medium with a concentration of approximately 1.7 x 10(4) protozoa/ml were prepared with (0.01 %) and without riboflavin. Exposure of UVA (dose 5.475 J/cm(2)) took place twice, with each illumination period followed by culturing of 10 mu l in peptone yeast-extract glucose (PYG) medium for 7 days. Every suspension prepared had a non-exposed control solution. Determination of Acanthamoeba was conducted daily, by count in Burker chamber days 4 through 7 after exposure. Statistical analysis was done by repeated-measurement ANOVA and post-hoc analysis for unpaired samples.Results: The exposure of ultraviolet light resulted in an inhibited growth of Acanthamoeba compared to the non-exposed solutions, with a statistically significant reduction over time (p = 0.0003). The addition of riboflavin did not amplify the effect, and there were no tendencies for an interaction effect between UVA and riboflavin. The antiprotozoal effect of the UVA wavelength, utilized in CXL, is solely mediated by ultraviolet light, and riboflavin does not seem to amplify the antimicrobial efficacy.
|
|
| 31. |
|
|
| 32. |
- Makdoumi, Karim, et al.
(author)
-
Evaluation of antibacterial efficacy of photo-activated riboflavin using ultraviolet light (UVA)
- 2010
-
In: Graefe's Archives for Clinical and Experimental Ophthalmology. - : Springer Science and Business Media LLC. - 0721-832X .- 1435-702X. ; 248:2, s. 207-212
-
Journal article (peer-reviewed)abstract
- BACKGROUND: To evaluate the antibacterial efficacy of photo-activated riboflavin using Ultraviolet A (UVA) on three bacterial strains commonly detected in keratitis. METHODS: Three bacterial strains (Staphylococcus epidermidis, Staphylococcus aureus and Pseudomonas aeruginosa) were cultured on blood/hematin-agar plates and dispersed in PBS. Dispersion was done of 10 microl of bacterial stock-solutions in 90 microl of RPMI, where different riboflavin molarities had been added, to achieve a bacterial concentration of 1-4 x 10 (4)/ml. Riboflavin end molarities before illumination were 0, 100, 200, 300 and 400 microM. Each solution had a negative control. The solutions were illuminated with UVA (365 nm) for 30 minutes (5.4 J/cm(2)) and then continued for a total time of 60 minutes (10.8 J/cm(2)). A count of CFU was conducted after incubation and results compared. RESULTS: In all tested strains, a slight decrease of bacteria was seen when exposed to UV for 30 minutes. A doubling of the UV dose showed a marked decrease of bacterial count in all bacteria tested. The combination of UV and riboflavin showed a more extensive reduction of CFU, confirming an interaction effect between UV and riboflavin. CONCLUSION: Riboflavin photo-activation using UVA (365 nm) can achieve an extensive eradication of bacteria, and the combination is more potent in reducing bacterial number than UV alone.
|
|
| 33. |
- Makdoumi, Karim, et al.
(author)
-
Infectious keratitis treated with corneal crosslinking
- 2010
-
In: Cornea. - 0277-3740 .- 1536-4798. ; 29:12, s. 1353-1358
-
Journal article (peer-reviewed)abstract
- Purpose: To describe 7 eyes with severe infectious keratitis treated using collagen crosslinking (CXL) with riboflavin. Materials and Methods: Seven eyes of 6 patients with severe infectious keratitis were treated with corneal crosslinking. Three patients were contact lens users. Symptom duration before CXL ranged between 0 and 7 days. Corneal melting was present in all cases. Photodocumentation of the keratitis was carried out and repeated at follow-up. All but 1 patient received topical antibiotic treatment in addition to the CXL treatment. CXL was conducted according to the standardized protocol for keratoconus. Results: In all but 1 eye, patients experienced improvement in symptoms within 24 hours. Two patients reported no symptoms whatsoever at this time. Corneal melting was arrested and complete epithelialization was achieved in all cases. In the 2 eyes with hypopyon, this regressed completely within 2 days after the CXL. Follow-up ranged between 1 and 6 months. Discussion: Our experience based on the above and other cases suggest that CXL could be an effective tool in battling difficult cases of infectious keratitis. This treatment could present many advantages but will need further investigation.
|
|
| 34. |
- Makdoumi, Karim, 1977-, et al.
(author)
-
Levels of beta-trace protein in optic disc pit with macular detachment
- 2017
-
In: Acta Ophthalmologica. - : Wiley-Blackwell Publishing Inc.. - 1755-375X .- 1755-3768. ; 95:8, s. 815-819
-
Journal article (peer-reviewed)abstract
- BACKGROUND: To report beta-trace protein (βTP) levels in the subretinal fluid (SRF) of four patients with a macular detachment associated with optic disc pit (ODP).METHODS: Four patients with a serous retinal detachment involving the macula was operated by pars plana vitrectomy (PPV) with C2 F6 gas tamponade and peeling of internal limiting membrane (ILM). Patients with a follow-up period exceeding one year postoperatively were included in the study. The SRF was drained using a fine cannula without laser photocoagulation, and the samples were analysed using particle-enhancing nephelometry. The levels of βTP were compared to 20 routine cerebrospinal fluid (CSF) samples.RESULTS: In four of the five samples from SRF had relatively low βTP levels, with a mean concentration of 6.6 mg/l (range 2.0 to 23.1 mg/l) compared to 16.0 mg/l (range 6.3-26.8 mg/l) in CSF. The only SRF sample within the range corresponding to normal CSF was the first sample from patient 4, and the analysis of the renewed aspirate during the second operation was 2.8 mg/l. Postoperatively, the regression of SRF was slow, but regression of SRF in the foveal region took place in all cases; however, visual acuity (VA) was improved in only half of the patients.CONCLUSION: The results from the analysed SRF regarding βTP concentration in these patients indicate that the SRF in ODP is not identical to CSF, as the concentrations of βTP differ.
|
|
| 35. |
|
|
| 36. |
|
|
| 37. |
|
|
| 38. |
- Makdoumi, Karim, 1977-, et al.
(author)
-
UVA-riboflavin photochemical therapy of bacterial keratitis : a pilot study
- 2012
-
In: Graefe's Archives for Clinical and Experimental Ophthalmology. - New York, USA : Springer. - 0721-832X .- 1435-702X. ; 250:1, s. 95-102
-
Journal article (peer-reviewed)abstract
- Background: The aim of this work as to investigate the photochemical interaction used in corneal crosslinking (CXL) as the primary therapy for bacterial keratitis.Methods: A prospective non-randomized study was conducted including 16 patients with a clinical diagnosis of bacterial keratitis. No patient had any prior antibiotic treatment for the current infection. Photography and microbial culturing of the infected cornea were performed. Riboflavin was topically administered for 20 min and ultraviolet light (UVA) exposure settings for treatment of keratoconus were used. After the procedure, clinical examinations were done at least once daily until signs of improvement had been established. The frequency of examinations was thereafter reduced. Antibiotic therapy was initiated if infectious progression was suspected. The trial was registered at ISCRTN.org (no: 21432643).Results: All eyes responded to the photochemical treatment with improvement in symptoms and signs of reduced inflammation. Epithelial healing was achieved in all cases. Antibiotic administration was necessary in two cases. One patient required a human amniotic membrane transplant.Conclusions: This trial illustrates that photosensitization of riboflavin using UVA at 365 nm has the potential to induce healing in patients with microbial keratitis. The results from the treatment of these 16 patients with corneal ulcers indicate that UVA-riboflavin photochemical therapy merits a controlled study in order to assess its efficacy and safety compared to antibiotics.
|
|
| 39. |
- Makdoumi, Karim, 1977-, et al.
(author)
-
Vasoproliferative retinal tumours in a Swedish population
- 2011
-
In: Acta Ophthalmologica. - : Wiley-Blackwell Publishing Inc.. - 1755-375X .- 1755-3768. ; 89:1, s. 91-94
-
Journal article (peer-reviewed)abstract
- Purpose: To describe the clinical appearance and the visual outcome of a cohort of patients with vasoproliferative retinal tumours (VPRTs) that were diagnosed and treated between 2002 and 2007 at the University Hospital of Orebro.Methods: Nine patients with diagnosed VPRTs were included in a retrospective study. The mean age at the time of diagnosis was 50.2 years (range 7-74 years). Follow-up time ranged between 14 and 83 months (mean 42.6). Nine out of ten eyes received cryotherapy; six eyes were also treated with photocoagulation. One patient was treated with intravitreal injections of ranibizumab (Lucentis((R))) and another was referred for brachytherapy. Because of persisting macular oedema, one eye was treated with intravitreal injection of triamcinolon.Results: Of the treated eyes, one had anterior uveitis, six had macular oedema at baseline and four had an exudative retinal detachment at the time of diagnosis. Seven eyes underwent vitrectomy because of epiretinal membranes. Visual acuity at diagnosis was 0.21 (mean) (range 0.02-0.6) and at latest check-up 0.30 (mean) (range light perception (LP)-1.0), with improvement in six eyes and deterioration in two. Two out of four patients with retinal detachment were successfully treated surgically.Conclusion: VPRTs are benign intraretinal changes. Several complications are associated with this condition. All patients in this study had symptom-giving tumours and six patients (six eyes) already had profound macular oedema at presentation. In these cases, when complications have already developed, the final visual prognosis is poor, thereby making it important to detect these tumours early. The patient who received anti-vascular endothelial growth factor (VEGF; Lucentis) therapy showed a slow improvement and distinct regression in exudations during the follow-up time. However, no increase in visual acuity was seen. At latest examination a peripheral exudative retinal detachment was still observed. Whether anti-VEGF treatment is effective, as either an alternative or complementary therapy, must be established in the future.
|
|
| 40. |
- Pritchard, Christopher D., et al.
(author)
-
Evaluation of viscoelastic poly(ethylene glycol) sols as vitreous substitutes in an experimental vitrectomy model in rabbits
- 2011
-
In: Acta Biomaterialia. - Oxon, United Kingdom : Elsevier. - 1742-7061 .- 1878-7568. ; 7:3, s. 936-943
-
Journal article (peer-reviewed)abstract
- The aim of this study was to employ an experimental protocol for in vivo evaluation of sols of 5 wt.% poly(ethylene glycol) (PEG) in phosphate-buffered saline as artificial vitreous substitutes. A 20 gauge pars plana vitrectomy and posterior vitreous detachment were performed in the right eye of eight pigmented rabbits. Approximately 1 ml of the viscoelastic PEG sols was then injected into the vitreous space of six eyes. PEG with an average molecular weight of 300,000 and 400,000 g mol(-1) was used in two and four eyes, respectively. Two eyes received balanced salt solution and served as controls. Full-field electroretinography was carried out and intra-ocular pressure (IOP, palpation) measured pre- and post-operatively at regular intervals up to 41 days. The rabbits were killed and the eyes examined by retinal photography, gross macroscopic examination and histology. The viscoelastic sols were successfully injected and remained translucent throughout the post-operative period, with some inferior formation of precipitates. None of the eyes displayed IOP elevation post-operatively, but in three of the PEG sol injected eyes transient hypotony was noted. One eye sustained retinal detachment during surgery and another two in the post-operative period. ERG recordings confirmed preservation of retinal function in three out of four eyes injected with 400,000 g mol(-1) PEG. Histological examination revealed up-regulation of glial acidic fibrillary protein in Müller cells in PEG sol injected eyes, but normal overall morphology in eyes with attached retinas. The viscosity of the sol was not retained throughout the post-operative period, indicating the demand for polymer cross-linking to increase residence time. The results provide promising preliminary results on the use of PEG hydrogels as a vitreous substitute.
|
|
| 41. |
- Schulz-Key, Steffen, et al.
(author)
-
Longterm follow-up of pars plana vitrectomy for vitreous floaters : complications, outcomes and patient satisfaction
- 2011
-
In: Acta Ophthalmologica. - : Wiley. - 1755-375X .- 1755-3768. ; 89:2, s. 159-165
-
Journal article (peer-reviewed)abstract
- Purpose: Floaters caused by degenerative or postoperative changes in the vitreous can interfere with all aspects of visual functioning. The aim of this study is to report the longterm outcome of pars plana vitrectomy (PPV) for persistent vitreous opacities. Methods: In a retrospective, non-randomized, interventional case study we reviewed all cases of vitreous floaters that were vitrectomized at our department between 1997 and 2006. Patient complaints and satisfaction were assessed by a questionnaire administered at the end of follow-up. Results: Seventy-three consecutive cases were included (61 patients). Mean Snellen best corrected visual acuity (BCVA) before surgery was 0.81. Overall, 85% of patients complained of severe or very severe difficulty caused by floaters. A total of 42% of eyes were pseudophakic, four of which were operated with combined PPV and phacoemulsification. Mean follow-up time was 37 months. Of the phakic eyes, 60% were operated for cataract during follow-up. One retinal detachment (RD) occurred immediately postoperatively (1.3%) and another four eyes developed RD during longterm follow-up 24-44 months after PPV (5.5% of cases). Postoperative BCVA remained mostly unchanged. Overall, 88% of patients were satisfied with the results of the operation. Conclusions: Some patients make considerable complaints as a result of vitreous opacities and their distress does not correlate with visual acuity. Vitrectomy is a safe and effective procedure with which to help these patients. Patients should be informed about the risk of cataract progression, unexpected inflammatory reaction and an increased risk for RD several years after PPV (5.5%).
|
|
| 42. |
- Slidsborg, Carina, et al.
(author)
-
Experts do not agree when to treat retinopathy of prematurity based on plus disease
- 2012
-
In: British Journal of Ophthalmology. - London, United Kingdom : B M J Publishing Group. - 0007-1161 .- 1468-2079. ; 96:4, s. 549-553
-
Journal article (peer-reviewed)abstract
- Objectives: To investigate inter-reader agreement on five severity levels of central vascular changes (none, mild, moderate, severe pre-plus disease, plus disease) and aggressive posterior retinopathy of prematurity (ROP), and to see whether an unintended shift in indication for treatment occurred.Methods: Four international ROP readers participated. Before the grading of the photographs, the readers were informed that a high proportion of advanced ROP cases were included. In total, 243 photographs/948 quadrants were available from 136 infants. As a standard series of photographs was available, grading was performed under optimised conditions.Results: The four readers agreed on the quadrant scores of only 70 (7.38%) of the 948 quadrants-that is, on 1, 5, 15, 4 and 45 quadrants for scores 0, 1, 2, 3 and 4, respectively. The mean scores differed systematically between the readers (permutation test, p<0.0001). Agreement on presence of aggressive posterior ROP from all four readers was not obtained for any of the photographs. Readers scored plus disease in at least two quadrants in 95.5% of the eyes for which treatment was indicated. All four readers agreed on the scoring of indication for treatment for 195 eyes (80.2%); however, treatment was only recommended in 18 (7.4%) eyes. One reader was found to differ systematically from the others in indicating treatment (Rasch analysis; p=0.0001). Finally, a significant shift in indication for treatment occurred between birth period 2000-2002 and 2003-2006 (Mann-Whitney rank sum test, p<0.001).Conclusions: Inter-reader agreement on central vascular changes is poor, especially when based on more than two rating categories. The subjective nature of diagnosing such vascular changes possibly resulted in earlier treatment of preterm infants in Denmark over the entire study period (1997-2006). The recent increased incidence of treated infants in Denmark is, at least in part, explained by a significant shift in indication for treatment.
|
|
