| 1. |
- Andersson-Engels, S., et al.
(författare)
-
Tissue diagnostics using laser-induced fluorescence
- 1989
-
Ingår i: Berichte der Bunsengesellschaft für Physikalische Chemie. - : Wiley. - 0005-9021. ; 93:3, s. 335-342
-
Tidskriftsartikel (refereegranskat)abstract
- We have performed extensive investigations of laser-induced fluorescence in animal and human tissue aimed at instant tissue characterization. Autofluorescence, as well as specific fluorescence from HPD/DHE and other photosensitizers, has been utilized. The studies have been focused on the demarcation of malignant tumours and atheroscleortic plaques. A nitrogen laser or an excimer-pumped dye laser was used to induce fluorescence, which was analysed with an intensified optical multichannel system. A fibre-optic sensor system was developed for the clinical work. Multi-colour fluorescence imaging has also been demonstrated along a line and equipment for two-dimensional imaging is being constructed. Dimensionless spectroscopic functions, which are not affected by factors that are clinically uncontrollable have been employed for optimum tissue discrimination. The investigations have so far been performed in a time-integrated mode, but time-resolved studies are now being initiated to fully exploit the diagnostic power of tissue laser-induced fluorescence. In addition to a presentation of our own work a brief review of tissue fluorescence studies performed by other groups is also given.
|
|
| 2. |
- Andersson-Engels, S., et al.
(författare)
-
Aspects of tumour demarcation in rats by means of laser-induced fluorescence and haematoporphyrin derivatives
- 1988
-
Ingår i: Lasers in Medical Science. - 0268-8921. ; 3:239, s. 239-248
-
Tidskriftsartikel (refereegranskat)abstract
- The effects of different parameters of interest for the localization of malignant tumours in situ by means of laser-induced fluorescence and haematoporphyrin derivatives were investigated. Such parameters are drug composition, drug concentration, laser pulse energy and excitation wavelength. In order to assess the relative merits of the two tumour-seeking agents Photofrin (haematoporphyrin derivative) and Photofrin II (dihaematoporphyrin ether) we have performed a comparative study on rat tissues. The results suggest that Photofrin is at least as good as the therapeutically more potent agent Photofrin II. A linear relation between drug dose and recorded porphyrin fluorescence intensity was also found. Using not only the porphyrin fluorescence, but also natural tissue autofluorescence, better tumour demarcation is observed when utilizing an excitation wavelength shorter than the porphyrin excitation peak at 405 nm.
|
|
| 3. |
|
|
| 4. |
- Andersson, P. S., et al.
(författare)
-
TISSUE CHARACTERIZATION USING LASER-INDUCED FLUORESCENCE.
- 1987
-
Ingår i: Conference on Lasers and Electro-Optics. - 0936659491 ; 14, s. 46-48
-
Konferensbidrag (refereegranskat)abstract
- In cancer tumor detection, tissue autofluorescence and characteristic features of injected hematoporphyrin derivative (HPD) can be utilized. The authors have studied the importance of the excitation wavelength for the achievable contrast between tumor and surrounding tissue using a rat tumor model. They have also compared the relative merits of two HPD preparations for tumor fluorescence detection. The real-time capability of the fluorescence technique is discussed.
|
|
| 5. |
- Ingemarsson, Ingemar, et al.
(författare)
-
Effects of isradipine, a new calcium antagonist, on postpartum uterine activity
- 1989
-
Ingår i: Acta Obstetricia et Gynecologica Scandinavica. - : Wiley. - 1600-0412 .- 0001-6349. ; 68:8, s. 725-730
-
Tidskriftsartikel (refereegranskat)abstract
- The effects of a new calcium antagonist, isradipine (PN 200-110) on postpartum uterine activity and the maternal cardiovascular system were investigated. Uterine activity was recorded by a microtip transducer catheter inserted transcervically within 45 min of normal vaginal delivery. 0.5 mg of isradipine was given as a bolus injection during 5 min to 7 women with spontaneous uterine activity and 1 mg was given during a 15-min period to another 8 women with oxytocin-stimulated uterine activity. Matched controls with similar pre-injection activity (+/- 5%) but not given the drug were selected for comparison. The effects of the drug in 3 women (given 1 mg of isradipine) were compared with those in matched controls and in women given 0.25 mg of terbutalin i.v. as a bolus injection. Isradipine had a marked inhibitory effect on both spontaneous and oxytocin-stimulated uterine activity. The inhibitory effect of 1 mg of isradipine seemed comparable to that of 0.25 mg of terbutalin. The inhibition occurred within 1-2 min after the injection and was sustained throughout the study period (2 h). A transient reduction of the systolic (mean maximum decrease 10-15%) and diastolic blood pressure (mean maximum decrease 15-20%) was seen, particularly during the injection period. Hypotension (systolic blood pressure less than 80 mmHg) was not recorded. A moderate increase in pulse rate (mean maximum increase 22-27%) was seen in all cases. The results show that isradipine given as a bolus injection can inhibit early postpartum uterine activity, with minimal side effects.
|
|
| 6. |
|
|
| 7. |
- Andersson-Engels, S., et al.
(författare)
-
A Comparison of tumor demarcation potential for various hematoporphyrin derivatives and phtalocyanine using laser-induced fluorescence
- 1988
-
Ingår i: Proceedings of SPIE - The International Society for Optical Engineering. - : SPIE. - 0277-786X. ; 907, s. 80-86
-
Konferensbidrag (refereegranskat)abstract
- Laser-induced fluorescence data for rats injected with the different tumor-marking drugs, dihematoporphyrin ether, poly hematoporphyrin esters, hematoporphyrin and phtalocyanine, are presented. Studies were performed at two different excitation wavelengths. Comparisons between the different drugs are made with regard to fluorescence intensity and tumor demarcation capability. Further, the origin of the differences in fluorescence characteristics is briefly di scussed.
|
|
| 8. |
- Andersson, S., et al.
(författare)
-
Tumour Localization by Means of Laser-Induced Fluorescence in Hematoporphyrin Derivative (HPD) — Bearing Tissue
- 1985
-
Ingår i: Laser Spectroscopy VII : Proceedings of the Seventh International Conference, Hawaii, June 24-28, 1985 - Proceedings of the Seventh International Conference, Hawaii, June 24-28, 1985. - Berlin, Heidelberg : Springer Berlin Heidelberg. - 9783662152539 - 9783540396642 ; , s. 401-406
-
Konferensbidrag (refereegranskat)abstract
- Following systemic injection, hematoporphyrin derivative (HPD) is known to be selectively retained in malignant tissue. This property can be used in a two-fold way: a) for localizing tumours by observing the characteristic dual-peaked laser-induced fluorescence from HPD, and b) for photodynamic therapy (HPD-PDT) using a localized HPD-assisted singlet oxygen release induced by irradiation of 630 nm laser light. This rapidly developing field has recently been reviewed by DOUGHERTY.
|
|
| 9. |
|
|
| 10. |
|
|
