La photothérapie dynamique : résultats cliniques et indications actuelles. - 08/03/08
U (Lübeck, Allemagne) Sschmidt-Erfurth
Background. Photodynamic therapy (PDT) was recently added to the spectrum of therapeutic options in the treatment of neovascular disease. Prospective, randomized clinical trials have proven benefit in choroidal neovascularization (CNV) due to age-related macular degeneration (AMD), CNV associated with pathologic myopia (PM) and CNV due to other pathologies of the macula. Prospective pilot series have furthermore demonstrated useful applications of the modality in patients with intraocular hemangioma.
Patients and method. PDT is performed using verteporfin as a sensitizing agent at a drug dose of 6 mg/m body surface administered intravenously over a 10 min. infusion. Irradiation is started 5 min after i.v. application at a non-thermal light intensity of 600mW/cm 2 applied as a single spot. Recommended light doses are 50J/cm 2 for CNV due to AMD or PM. A light exposure of 100J/cm 2 2 was used in hemangiomas.
Results. Predominantly classic CNV lesions showed the highest benefit during the longest follow-up. After 2 years visual stabilization was maintained in 59% of verteporfin-treated eyes as compared to 31% of placebo-treated eyes. This benefit was sustained during following years of observation. In eyes with PM-related CNV visual improvement was more frequent with an increase in visual acuity of at least 1 line in 39% of treated eyes, but prevention of visual loss was found to be less reliable. In exclusively occult CNV the primary visual acuity and to a lesser degree the initial size of the lesion predicted the outcome: A better prognosis was seen in eyes with a visual acuity below 20/50 and a CNV size of less than 4 disc areas. Indocaynine green angiography and topographic imaging revealed a high risk for persistent choroidal damage in frequent retreatments. Choroidal hemangiomas respond extremely favourably to PDT with regression of the tumor, resolution of exudation and substantial improvement in vision. The functional outcome of retinal hemangiomas is poor despite anatomical success.
Conclusion. PDT is a modality which offers reliable and clinically relevant benefit in a group of patients with choroidal neovascularization or subretinal hemangiomatous lesions. The level of improvement largely depends on the appropriate indication and correct selection of patients.
© 2002 Elsevier Masson SAS. Tous droits réservés.
Vol 25 - N° 5
P. 16 - avril 2002 Retour au numéroBienvenue sur EM-consulte, la référence des professionnels de santé.