| 1. |
- Källén, Karin, et al.
(author)
-
Ophthalmologic Outcome of Extremely Preterm Infants at 6.5 Years of Age Extremely Preterm Infants in Sweden Study (EXPRESS)
- 2016
-
In: Jama Ophthalmology. - : American Medical Association (AMA). - 2168-6165 .- 2168-6173. ; 134:5, s. 555-562
-
Journal article (peer-reviewed)abstract
- IMPORTANCE This follow-up study of extremely preterm (EPT) children (<27 weeks' gestational age [GA] at birth) revealed major eye and visual problems in 37.9%(147 of 388) of all EPT infants and in 55.4%(67 of 121) of the most immature subgroups at 6.5 years of age. These major eye and visual problems were strongly associated with treatment-requiring retinopathy of prematurity (ROP). OBJECTIVES To investigate the ophthalmologic outcome of a national cohort of EPT children at 6.5 years of age and to evaluate the impact of prematurity and ROP. DESIGN, SETTING, AND PARTICIPANTS All surviving EPT children born in Sweden between April 1, 2004, and March 31, 2007, were included and compared with a matched term control group, as part of a prospective national follow-up study. MAIN OUTCOMES AND MEASURES Visual acuity, refraction in cycloplegia, and manifest strabismus were evaluated and compared with GA at birth and with treatment-requiring ROP. RESULTS The study cohort comprised 486 participants. The mean (SD) GA of the children who were included was 25 (1) weeks, and 45.7%(222 of 486) were female. At a median age of 6.6 years, 89.3%(434 of 486) of eligible EPT children were assessed and compared with 300 control group children. In the EPT group, 2.1%(9 of 434) were blind, 4.8%(21 of 434) were visually impaired according to the World Health Organization criteria, and 8.8% (38 of 434) were visually impaired according to the study criteria. Strabismus was found in 17.4% (68 of 390) and refractive errors in 29.7%(115 of 387) of the EPT children compared with 0% (0 of 299) and 5.9% (17 of 289), respectively, of the control children (P<.001). Altogether at 6.5 years of age, 37.9%(147 of 388) of the EPT children had some ophthalmologic abnormality compared with 6.2%(18 of 290) of the matched control group (95% CI of the difference, 26.1%-37.2%). When treatment-requiring ROP was adjusted for, no significant association between GA and visual impairment could be detected. For refractive errors, the association with GA remained after adjustment for treatment-requiring ROP (odds ratio, 0.72; 95% CI, 0.58-0.91 for each 1-week increment). CONCLUSIONS AND RELEVANCE In a Swedish national cohort of EPT children at 6.5 years of age, major eye and visual problems were frequently found. Treatment-requiring ROP was a stronger impact factor than GA on visual impairment and strabismus, but not on refractive errors, as a whole. In modern neonatal intensive care settings, ophthalmologic problems continue to account for a high proportion of long-term sequelae of prematurity.
|
|
| 2. |
- Parissi, Marlen, et al.
(author)
-
Corneal Nerve Regeneration After Collagen Cross-Linking Treatment of Keratoconus A 5-Year Longitudinal Study
- 2016
-
In: JAMA ophthalmology. - : AMER MEDICAL ASSOC. - 2168-6165 .- 2168-6173. ; 134:1, s. 70-78
-
Journal article (peer-reviewed)abstract
- IMPORTANCE It is unknown whether a neurotrophic deficit or pathologic nerve morphology persists in keratoconus in the long term after corneal collagen cross-linking (CXL) treatment. Nerve pathology could impact long-term corneal status in patients with keratoconus. OBJECTIVE To determine whether CXL treatment of keratoconus results in normalization of subbasal nerve density and architecture up to 5 years after treatment. DESIGN, SETTING, AND PARTICIPANTS Observational study of 19 patients with early-stage keratoconus indicated for a first CXL treatment with longitudinal follow-up to 5 years postoperatively (examinations were performed from 2009 to 2015; analysis was performed from February to May 2015) and 19 age-matched healthy volunteers at a primary care center and a university hospital ophthalmology department. EXPOSURE The patients with keratoconus underwent standard epithelial-off UV-A/riboflavin CXL treatment with 30-minute UV-A exposure at 3mW/cm(2) irradiance. MAIN OUTCOMES AND MEASURES Central corneal subbasal nerve density and subbasal nerve architecture by use of laser-scanning in vivo confocal microscopy; subbasal nerve analysis by 2 masked observers and by use of a fully automated method; wide-field mosaics of subbasal nerve architecture by use of an automated method; and ocular surface touch sensitivity by use of contact esthesiometry. RESULTS Mean (SD) age of the 19 patients with keratoconus was 27.5 (7.1) years (range, 19-44 years), and minimal corneal thickness was 428 (36) mu m (range, 372-497 mu m). Compared with the mean (SD) preoperative subbasal nerve density of 21.0 (4.2) mm/mm(2) in healthy corneas, the mean (SD) preoperative subbasal nerve density of 10.3 (5.6) mm/mm(2) in the corneas of patients with stage 1 or 2 keratoconus was reduced 51%(mean difference, 10.7 mm/mm(2) [95% CI, 6.8-14.6 mm/mm(2)]; P < .001). After CXL, nerves continued to regenerate for up to 5 years, but nerve density remained reduced relative to healthy corneas at final follow-up (mean reduction, 8.5 mm/mm(2) [95% CI, 4.7-12.4 mm/mm(2)]; P < .001) despite recovery of touch sensitivity to normal levels by 6 months. Preoperatively, more frequent nerve loops, crossings, and greater crossing angles were observed in the corneas of patients with keratoconus compared with healthy corneas. Postoperatively, the frequency of nerve looping increased, crossings were more frequent, and nerve tortuosity increased. Wide-field mosaics indicated persistent disrupted orientation of the regenerating subbasal nerves 5 years after CXL. CONCLUSIONS AND RELEVANCE Keratoconus is characterized by a neurotrophic deficit and altered nerve morphology that CXL treatment does not address, despite providing a positive biomechanical effect in the stroma. Given the widespread use of CXL in the management of patients with keratoconus, the progression of abnormal innervation after CXL should be recognized.
|
|
