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U Schmidt-Erfurth

Publications and source records attributed to U Schmidt-Erfurth.

At least 37 records · Page 2Linked to original sources
PubMed2001

Three-dimensional topographic angiography in chorioretinal vascular disease.

PURPOSE: To evaluate a new angiographic technique that offers three-dimensional imaging of chorioretinal vascular diseases. METHODS: Fluorescein (FA) and indocyanine green angiography (ICGA) were performed using a confocal scanning laser ophthalmoscope. Tomographic series with 32 images per set were taken over a depth of 4 mm at an image frequency of 20 Hz. An axial analysis was performed for each x/y position to determine the fluorescence distribution along the z-axis. The location of the onset of fluorescence at a defined threshold intensity was identified and a depth profile was generated. The overall results of fluorescence topography were displayed in a gray scale-coded image and three-dimensional relief. RESULTS: Topographic angiography delineated the choriocapillary surface covering the posterior pole with exposed larger retinal vessels. Superficial masking of fluorescence by hemorrhage or absorbing fluid did not preclude detection of underlying diseases. Choroidal neovascularization (CNV) appeared as a vascular formation with distinct configuration and prominence. Chorioretinal infiltrates exhibited perfusion defects with dye pooling. Retinal pigment epithelium detachments (PEDs) demonstrated dynamic filling mechanisms. Intraretinal extravasation in retinal vascular disease was detected within a well-demarcated area with prominent retinal thickening. CONCLUSIONS: Confocal topographic angiography allows high-resolution three-dimensional imaging of chorioretinal vascular and exudative diseases. Structural vascular changes (e.g., proliferation) are detected in respect to location and size. Dynamic processes (e.g., perfusion defects, extravasation, and barrier dysfunction) are clearly identified and may be quantified. Topographic angiography is a promising technique in the diagnosis, therapeutic evaluation, and pathophysiological evaluation of macular disease.

Choroid↗
PubMed2000

A preliminary study of photodynamic therapy using verteporfin for choroidal neovascularization in pathologic myopia, ocular histoplasmosis syndrome, angioid streaks, and idiopathic causes.

OBJECTIVE: To evaluate short-term safety and the effects on visual acuity and fluorescein angiography of single or multiple sessions of photodynamic therapy with verteporfin for choroidal neovascularization (CNV) not related to age-related macular degeneration (AMD), including pathologic myopia, the ocular histoplasmosis syndrome, angioid streaks, and idiopathic causes. DESIGN: A nonrandomized, multicenter, open-label, dose-escalation phase 1 and 2 clinical trial. SETTING: Four ophthalmic centers in Europe and North America providing retinal care. PARTICIPANTS: Thirteen patients with subfoveal CNV due to pathologic myopia, the ocular histoplasmosis syndrome, angioid streaks, or idiopathic causes. METHODS: Standardized protocol refraction, visual acuity testing, ophthalmic examinations, color photographs, and fluorescein angiograms were used to evaluate the results of photodynamic therapy treatments with verteporfin. Follow-up ranged from 12 weeks for patients who were treated once to 43 weeks for patients who were treated up to 4 times. RESULTS: Verteporfin therapy was well tolerated in patients with CNV not related to AMD. No deterioration in visual acuity was observed; most patients gained at least 1 line of vision. Reduction in the size of leakage area from classic CNV was noted in all patients as early as 1 week after verteporfin therapy, with complete absence of leakage from classic CNV in almost half of the patients. Improvement in visual acuity after verteporfin therapy was greatest (+6, +8, and +9 lines) in 3 patients with relatively poor initial visual acuity (between 20/200 and 20/800). Up to 4 treatments were found to have short-term safety even with retreatment intervals as short as 4 weeks. CONCLUSIONS: Treatment of CNV not related to AMD with verteporfin therapy achieves short-term cessation of fluorescein leakage from CNV in a small number of patients without loss of vision. Further randomized clinical trials including a larger number of patients are under way to confirm whether verteporfin therapy is beneficial for subfoveal CNV not related to AMD.

Adult↗
PubMed2000

[Correlation of morphologic changes between optical coherence tomography and topographic angiography in a case of gyrate atrophy].

PURPOSE: To characterize ultrastrructual changes in atrophic disease of the retina, RPE and choroid as seen with gyrate atrophy using two new diagnostic modalities, optical coherence tomography (OCT) and topographic angiography. PATIENT AND METHOD: OCT images were taken in a patient with pericentral choroidal atrophy using a slit-lamp-adapted OCT system. Ophthalmoscopy, conventional and topographic angiographic findings were correlated to the reflectivity changes as seen on OCT. RESULTS: Areas of chorioretinal atrophy correlated with a loss of reflectivity in the RPE-choriocapillaris complex on OCT. Additionally OCT identified a thinning of the nerve fiber layer. Topographic angiography demonstrated an extensive defect, seen as an area of depression, consistent with a loss of choriocapillaris and larger-sized choroidal vessels. In contrast to conventional angiography, central islands were not found to demonstrate structural intensity, while the midperipheral surrounding area was clearly elevated to physiological levels. CONCLUSION: OCT and topographic angiography provide in vivo insight into morphologic changes within neurosensory retina and choroid caused by pericentral choroidal atrophy.

Choroid↗
PubMed2000

Photodynamic therapy of choroidal hemangioma: two case reports.

BACKGROUND: Photocoagulation, cryotherapy and radiotherapy have been used to treat angiomatous lesions. Depending on the location of the angioma, these treatments can cause additional, significant functional damage. Photodynamic therapy (PDT) however, allows a selective occlusion of vascular lesions without damaging adjacent retinal structures. METHODS: Two patients with isolated choroidal hemangiomas involving the posterior pole were treated with PDT. Treatments were performed using a diode laser at 692 nm, a light dose of 100 J/cm2 and 6 mg/m2 body surface area verteporfin (BPD-MA). PDT was applied in two courses in one eye and in four in the other eye at 1-4 months intervals. Patients were followed up for 9-12 months with visual acuity measurements and dilated ophthalmoscopy. Ultrasound, indocyanine green angiographic and fluorescein angiographic images were evaluated at each visit. RESULTS: Tumor heights were 3.3 and 4.6 mm on pretreatment ultrasound. After therapy, patients with isolated choroidal hemangioma showed total regression of the lesion and improved visual acuity due to resorption of retinal edema. Serous retinal detachment and cystoid macular edema resolved. Ultrasound demonstrated a progressive decrease in tumor height after each PDT application, with complete disappearance of the lesion. Retinal vessels were not affected by the treatment, and retinal function recovered in areas with previous tumor involvement. CONCLUSION: PDT allows selective treatment of large intraocular angiomatous lesions. Without optimized parameters, complete regression of choroidal hemangiomas, resolution of secondary complications and improvement of visual acuity were documented.

Adult↗
PubMed2000

Confocal laser scanning fluorescence topography: a new method for three-dimensional functional imaging of vascular structures.

Three-dimensional topography of perfused vascular structures is possible via confocal laser scanning of intravascular fluorescence. The lateral resolution is given by the spot size of the scanning laser beam (optimally 10 microm at the retina). The axial resolution, however, depends on the accuracy of detection of the surface of the fluorescent structure, which is typically one order of magnitude higher (30 microm at the retina) than the confocal resolution. The vascular structure is stained with an appropriate fluorescent dye prior to the investigation using standard systemic dye injection. Confocal scanning of the fluorescence in planes of different depths within the vascular structure under investigation leads to a three-dimensional data set. Signal processing includes passive eye tracking, lateral averaging and axial determination of the surface of the fluorescent structure. The potential of this new technique is demonstrated by showing the topography of physiological vessel structures as well as of selected vascular diseases such as cone dystrophy, RPE detachment, choroidal haemangioma and retinal laser coagulation. Confocal laser angioscopic fluorescence topography (CLAFT) measures the three-dimensional surface structure of functional (perfused) vasculature and surrounding leakage. CLAFT may help to diagnose and quantify status and time course of vascular diseases.

Contrast Media↗
PubMed2000

[Choroidal changes after photodynamic therapy (PDT). A two-year follow-up study of 38 patients].

BACKGROUND: Photodynamic therapy is a new option for treatment of choroidal neovascularisation in patients with age-related macular degeneration. But choroidal changes and associated angiographic characteristics have not been further evaluated. PATIENTS: Indocyanine green angiography was used to follow 38 patients with subfoveal choroidal neovascularisation in age-related macular degeneration over up to two years. All patients were treated with the photosensitizer Benzoporphyrin Derivative-MA receiving either a single or triple treatment. RESULTS: Indocyanine green angiography shows two effects of photodynamic therapy. On the one hand a selective and lasting closure of choroidal neovascularisation was documented. Choroidal neovascularisation-size and leakage was significantly reduced in the entire treatment group to 20.7% and 28.3% one week after treatment, followed by a slow increase to 33.3% and 41.2% at up to two years longterm follow up. On the other hand photodynamic therapy causes typically a peri-lesional hypofluorescence in Indocyanine green angiography. This hypofluorescence is most likely due to choroidal hypoperfusion and vascular endothelial changes. A continuous increase in fluorescence was shown, reaching again 90% of the pretreatment intensity at 3 months, documenting a good recovery of the choroidal network. CONCLUSION: The results show that photodynamic therapy is an alternative treatment in age-related macular degeneration with choroidal, subfoveal neovascularisation. Indocyaningreen angiography reflects well choroidal changes associated with this therapy and may be helpful to choose treatment intervals.

Choroid↗
PubMed2000

[Micro-perimetric documentation of retinal function in photodynamic therapy of choroid neovascularizations].

PURPOSE: Photodynamic therapy provides occlusion of choroidal neovascularization by intravascular endothelial damage. The photodynamic approach offers the potential to occlude choroidal neovascularization selectively without altering adjacent sensory retina and therefore to preserve visual acuity. To determine the selectivity of photodynamic therapy photoreceptor function was measured by microperimetry allowing topic mapping of retinal function. METHODS: A Rodenstock scanning laser ophthalmoscope was used to document preservation of central visual fields before and after photodynamic therapy. Single photodynamic therapy without known efficient parameters was performed in 13 patients and repeated photodynamic therapy using optimised light doses was performed in 10 patients with subfoveal choroidal neovascularization using benzoporphyrin derivate (verteporfin). Intensity and dimension of central scotomas were measured, using a grading system of stimuli ranging from 0-32 dB. Areas of absolute and relative defect were defined and fixation localisation was monitored. Perimetric testing was done pre photodynamic therapy, one week, one month and three months post photodynamic therapy. RESULTS: Postoperative scotomas after single photodynamic therapy were smaller in 8%, identical in 61% and larger in 31% compared with preoperative findings. After repeated photodynamic therapy postoperative scotomas were smaller in 70%, identical in 30% and larger in no case. The observed increase was less than 25% of the original size. Postoperative defects were always significantly smaller than the entire size of the irradiated area. No new scotomas were found after photodynamic therapy. Angiographically visible occlusion post photodynamic therapy was in general larger than scotoma size. CONCLUSION: Documentation of the retinal function by microperimetry after photodynamic therapy of subfoveal choroidal neovascularization shows no new scotoma in the treated area. This can also be documented in the hypofluorescent area around the lesion one week after the treatment. After repeated treatment a reduced scotoma size due to choroidal neovascularization could be seen in 2/3 of the patients after 3 months. No initial vision loss as seen in conventional photocoagulation could be documented after photodynamic therapy.

Aged↗
PubMed1999

Photodynamic therapy with verteporfin for choroidal neovascularization caused by age-related macular degeneration: results of a single treatment in a phase 1 and 2 study.

OBJECTIVE: To evaluate the safety and short-term visual and fluorescein angiographic effects of a single photodynamic therapy treatment with verteporfin with the use of different dosage regimens in patients with choroidal neovascularization (CNV) from age-related macular degeneration. DESIGN: Nonrandomized, multicenter, open-label, clinical trial using 5 dosage regimens. SETTING: Four ophthalmic centers in North America and Europe providing retinal care. PARTICIPANTS: Patients with subfoveal CNV caused by age-related macular degeneration. METHODS: Standardized protocol refraction, visual acuity testing, ophthalmic examination, color photographs, and fluorescein angiograms were used to evaluate the effects of a single treatment of photodynamic therapy with verteporfin. Follow-up was planned through 3 months in 97 patients and for less than 3 months in 31 other patients. RESULTS: The mean visual acuity change (and range of change) from baseline at the follow-up examination at week 12 after a single treatment with regimens 1 through 5 was -0.2 (-3 to +2), -0.9 (-9 to +5), -1.6 (-9 to +2), +0.4 (-8 to +7), and +0.1 (-8 to +9) lines, respectively. Only the highest light dose (150 J/cm2) in regimens 2 and 3, which produced angiographic nonperfusion of neurosensory retinal vessels, caused marked vision loss. Some cessation of fluorescein leakage from CNV was achieved without loss of vision when the light dose used was less than 150 J/cm2. Systemic adverse events were rare. Cessation of fluorescein leakage from CNV was noted in all regimens by 1 week after photodynamic therapy. Fluorescein leakage from at least a portion of the CNV reappeared by 4 to 12 weeks after treatment in almost all cases. Progression of classic CNV beyond the area of CNV identified before treatment was noted in 42 (51%) of the 83 eyes with classic CNV followed up for 3 months after a single treatment. Eyes in which the area of any CNV leakage at 12 weeks was less than at baseline had a significantly better visual acuity outcome (+0.8 line) than eyes in which CNV leakage progressed (-0.8 line). CONCLUSIONS: Photodynamic therapy with verteporfin achieved short-term cessation of fluorescein leakage from CNV without loss of vision or growth of classic CNV in some patients with age-related macular degeneration. Except for nonperfusion of neurosensory retinal vessels at a light dose of 150 J/cm2, no other adverse events were of concern. Randomized clinical trials to investigate whether this new modality can preserve vision in patients with CNV secondary to age-related macular degeneration are justified.

Aged↗
PubMed1999

Photodynamic therapy with verteporfin for choroidal neovascularization caused by age-related macular degeneration: results of retreatments in a phase 1 and 2 study.

OBJECTIVES: To evaluate safety and short-term visual acuity and fluorescein angiographic effects of photodynamic therapy (PDT) after retreatments with verteporfin for choroidal neovascularization (CNV) in age-related macular degeneration (AMD) that demonstrated fluorescein leakage after at least 1 course of PDT. DESIGN: Nonrandomized, multicenter, open-label phase 1 and 2 clinical trial using 2 different retreatment dosage regimens. SETTING: Four ophthalmic centers in Europe and North America providing retinal care. METHODS: Standardized protocol refraction, visual acuity testing, ophthalmic examinations, color photographs, and fluorescein angiograms were used to evaluate the results of multiple PDT treatments. Two regimens (regimens 2 and 4) for treatment and retreatment were chosen from 5 used in a single-treatment study. Both regimens used a verteporfin dose of 6 mg/m2 infused for 10 minutes. However, regimen 2 used a light dose of 100 J/cm2 applied 20 minutes after the start of the verteporfin infusion, whereas regimen 4 used a light dose of 50, 75, or 100 J/cm2 applied 15 minutes after infusion commenced. Posttreatment evaluations were planned in 31 participants up to 3 months after up to 2 retreatments given at 2- or 4-week intervals after initial PDT treatment. Similar posttreatment evaluations were planned after retreatments in 5 additional participants who were reenrolled some time more than 12 weeks after an initial PDT treatment. RESULTS: The average visual acuity change for the 31 participants who had retreatment within 2 to 4 weeks after the initial treatment and a follow-up examination 16 to 20 weeks after the initial treatment was 0.2 lines (range, -4 to 4 lines) in regimen 2 and -1.0 line (range, -5 to 3 lines) in regimen 4. Similar outcomes were noted in the 5 reenrolled participants. Cessation of fluorescein leakage from classic CNV for at least 1 to 4 weeks could be achieved without loss of visual acuity after at least 2 treatments in 2 (6.5%) of 31 patients. Similar to single-treatment effects, the disappearance of leakage was documented regularly at 1 week after each retreatment. Fluorescein leakage reappeared by 4 to 12 weeks after a retreatment in almost all cases. However, compared with baseline, leakage activity appeared to be reduced after multiple PDT courses. For the 31 patients who had follow-up for 3 months after the last retreatment and had received retreatment 2 to 4 weeks after the initial treatment, progression of CNV beyond the area identified before the retreatment was noted in 10 (48%) of the 21 eyes with classic CNV in regimen 2 and 9 (90%) of 10 eyes in regimen 4. The rate and severity of ocular or systemic adverse events were not increased by multiple applications. CONCLUSIONS: Multiple applications of PDT with verteporfin achieve repetitive, short-term cessation of fluorescein leakage from CNV secondary to AMD, without loss of visual acuity. This strategy can be used in randomized clinical trials investigating the efficacy of verteporfin in PDT for recurrent fluorescein dye leakage from persistent or recurrent CNV, following an initial or subsequent PDT treatment, with maintenance of visual acuity. Retreatments may achieve progressive cessation of leakage and prevent further growth of CNV and subsequent visual loss.

Aged↗
PubMed1999

[Photodynamic therapy: ICG angiography findings].

PURPOSE: Photodynamic therapy (PDT) has been shown to provide immediate occlusion of choroidal neovascularization (CNV), followed by recurrent leakage after single PDT in the majority of the cases after 3 months. Indocyanine green angiography (ICG-A) was used to evaluate completeness of CNV occlusion, effects on physiological choroid and patterns of CNV recurrence. METHODS: ICG-A was performed using a confocal laser scanning ophthalmoscope (HRA) before PDT at 1 week, 4 and 12 weeks following PDT. Twenty patients with single and 10 patients with repeated PDT treatments with administration of benzoporphyrin derivative and radiant exposures between 50 and 150 J/cm2 were evaluated. RESULTS: Before PDT well-defined CNV was detectable during early ICG-A in all lesions. Depending on the number of treatments, CNV was absent in early phase ICG-A in 46-83%. CNV reappeared at week 4 in many and at 12 weeks in 77 (66%) of the cases. The treated area regularly showed hypofluorescence, which persisted until week 12. The intensity of choroidal hypofluorescence showed wide interindividual variability. Recurrence may originate from persistent feeder vessels. CONCLUSION: With ICG-A we demonstrated that PDT induces hypofluorescence of CNV and choroid possibly due to perfusion changes or blockade phenomena. Recurrence may be due to reperfusion of the preexisting CNV or regrowth from feeder vessels.

Adult↗
PubMed1999

[Confocal indocyanine green angiography with 3-dimensional topography. Results in choroid neovascularization (CNV)].

BACKGROUND: Confocal indocyanin green angiography (ICGA) offers detailed two-dimensional imaging of choroidal pathologies. However, the spatial extension of lesions is not reproduced. We developed a novel method for three-dimensional documentation of choroidal vascular abnormalities. METHODS: Focal series were performed using a laser scanning ophthalmoscope (Heidelberg Retina Angiograph). Thirty-two images within a distance of 4 mm were taken at a frequency of 20 Hz. Following correction of dislocation, a surface of normalized fluorescence intensity was determined and displayed topographically. RESULTS: In physiological eyes three-dimensional ICGA demonstrates the homogeneous concavity of the choroid with prominent overlay of retinal vessels. Classic choroidal neovascularization (CNV) imposes as substantial elevation. Occult CNV are demarcated despite negative conventional ICGA due to reduction of blocking phenomena. Therapeutic interventions such as photocoagulation, photodynamic therapy and surgery induce a resolution of CNV with or without residual defects within the choroidal pattern. CONCLUSION: Topographic ICGA allows for the first time in-vivo representation of prominence and depth of vascularized pathologies and provides a tool for improved diagnostic and therapeutic evaluation.

Choroidal Neovascularization↗
PubMed1999

Macular injury by a military range finder.

OBJECTIVE: The authors report the clinical findings of a civilian patient who unintentionally looked into the laser beam of a military range finder. Detailed information on the range finder is given. The objective is to illustrate the potential danger of such devices and to give detailed information on the device, the clinical findings associated with exposure, and the laser-tissue interaction mechanism. METHODS: The patient was examined with fluorescein angiography, indocyanine green angiography, microperimetry, and optical coherence tomography, both in the acute stage (2 hours) and 4 weeks later. Fluorescein angiography was performed again 4 months later. A total of 100 mg prednisone tapered over 9 days was prescribed. Additionally, 50 microg tissue plasminogen activator (TPA) and 0.5 mL pure C2F6 were injected in the vitreous. RESULTS: In the acute phase, hemorrhage was located beneath the retina, primarily beneath the retinal pigment epithelium. Retinal defects as seen initially over the subretinal blood were reduced after 4 weeks, but a retinal defect ranging from the lasered site toward the fovea remained. Visual acuity slightly increased from 20/100 to 20/63 after 4 weeks. Indocyanine green angiography showed a large hypofluorescent spot in the macula. Four months after the accident, a classic choroidal neovascularization developed, originating from the lasered site. The technical parameters of the range finder were: Nd:YAG laser (1,064 nm), pulse duration 10 ns, beam divergence 1.5 mrad, energy 10 mJ. CONCLUSION: A range finder can produce severe macular injury. The primary laser-tissue interaction mechanism seems to be explosive disruption of choroidal tissue. Intravitreal injection of TPA and C2F6 did not show a clear benefit to such laser lesions. A late complication can be secondary choroidal neovascularization.

Adult↗
PubMed1999

Indocyanine green angiography and retinal sensitivity after photodynamic therapy of subfoveal choroidal neovascularization.

Photodynamic therapy (PDT) is currently being evaluated in clinical trials for the treatment of choroidal neovascularization (CNV). Preliminary results indicate that PDT achieves immediate absence of leakage from CNV while maintaining visual acuity. Indocyanine green angiography reveals a reduction in CNV size and a persistent decrease in leakage activity after PDT. PDT appears to be characteristically accompanied by choroidal perfusion changes that regularly resolve within 3 months. Microperimetry shows an improvement of the central visual field with a decrease in scotoma size and intensity. Repeated PDT applications do not cause additional damage to the treated area, but might further enhance the recovery of macular function. A placebo-controlled, multi-center trial (TAP trial) evaluating the benefit of repeated PDT treatments in 3-month intervals is currently underway.

Choroidal Neovascularization↗
PubMed1998

[Photodynamic therapy. Minimally invasive treatment of choroidal neovascularization].

The exudative stage of age-related macular degeneration (AMD) with choroidal neovascularization (CNV) commonly leads to rapidly progressive visual loss. Conventional laser coagulation with its unspecific destruction of the CNV, including adjacent retinal structures, often causes an additional reduction in visual acuity, particularly in cases with central localization of the pathological process. Photodynamic therapy (PDT) induces selective occlusion of CNV via light-induced pharmacological thrombosis without any damage to the retina in the macular area. Pilot studies have demonstrated complete occlusion of CNV with subsequent restoration of retinal function. Even repeated application was not associated with any alteration of the photoreceptor layer. The treatment strategy in PDT consists of repetitive thrombosis of CNV with progressive occlusion of the exudative lesion adjusted to the angiographic appearance. A randomized multicenter trial is currently underway and is evaluating the long-term visual results documented in 609 patients with subfoveal CNV who underwent control and eventual PDT at 3-month intervals. If PDT proves to be beneficial, an easy and non-invasive treatment modality could be offered to numerous patients who demonstrated occult classic CNV and are otherwise facing an extremely poor prognosis.

Choroidal Neovascularization↗
PubMed1998

[Lipid metabolism in retinal pigment epithelium. Possible significance of lipoprotein receptors].

PURPOSE: The retinal pigment epithelium (RPE) regulates the lipid metabolism of the photoreceptors by catalysis of membrane outer segments and via choriocapillary perfusion is also exposed to the regulation of blood lipid levels. Since the uptake the metabolism of cholesterol are mediated by specific low-density lipoprotein (LDL) receptors, expression and regulation of this receptor-type were studied in RPE cultures. METHODS: In vitro experiments were carried out in transformed (SV40) human RPE cells. Human fibroblasts were used as a comparative cell line with known receptor expression. LDL was coupled to a fluorescent marker (Dil); receptor binding was quantified by flow cytometry. Expression and saturation characteristics were determined. LDL metabolism was examined by variation of the temperature (4 and 37 degrees C). LDL and Dil-LDL showed competition at the receptor. RESULTS: RPE cells demonstrated a higher uptake of Dil-LDL than fibroblasts. Expression could be further stimulated by culture conditions. Uptake kinetics were saturable with complete saturation at 50 micrograms/ml Dil-LDL. LDL uptake was shown to be temperature-dependent, indicating an energy-dependent pathway. CONCLUSIONS: RPE cells exhibit significant expression of receptors for native LDL, possibly mediating the lipid metabolism of the RPE-photoreceptor complex, as well as the uptake of blood lipids. Lack of regulation of the receptor for LDL may lead to intracellular accumulation of lipids, which may play a role in the pathogenesis of AMD.

Cholesterol↗
PubMed1998

Photodynamic therapy of subfoveal choroidal neovascularization: clinical and angiographic examples.

BACKGROUND: Conventional photocoagulation of subfoveal choroidal neovascularization (CNV) is often accompanied by visual loss due to thermal damage to adjacent retinal structures. Photodynamic therapy (PDT) allows vascular occlusion by selective photochemical destruction of vascular endothelial cells only. In a pilot study we evaluated the use of PDT in CNV. METHODS: In a clinical phase I/II trial, patients with subfoveal CNV were treated with PDT. Benzoporphyrin derivative monoacid ring A (BPD) was used as sensitizer at a drug dose of 6 mg/m2 or 12 mg/m2. Irradiation was performed via a diode laser emitting at 690 nm coupled into a slit lamp. Safe and maximum tolerated light doses were defined by dose escalation from 25 to 150 J/cm2. Photodynamic effects were documented ophthalmoscopically and angiographically. RESULTS: Sixty-one patients received a single course of BPD-PDT. Preliminary results suggest no damage to retinal structures within the treated area clinically. Retinal perfusion was not altered, while CNV demonstrated immediate absence of fluorescein leakage in the majority of lesions subsequent to PDT. At optimized parameters (6 mg/m2 and 50 J/cm2) complete cessation of leakage from classic CNV occurred in 100% of cases at 1 week and in 50% at week 4. In 70-80% of classic CNV, leakage reappeared at week 12, but markedly less than before treatment. CONCLUSION: PDT allows temporary absence of leakage from CNV with preservation of visual acuity. The long-term prognosis of CNV secondary to age-related macular degeneration treated with repeated courses of PDT is being evaluated in a phase III trial.

Adult↗