ABSTRACT
BACKGROUND: Photodynamic therapy (PDT) with verteporfin is used for treatment of choroidal neovascularization in several conditions. Platelet aggregation is one of the mechanisms by which PDT is thought to work. This study sought to examine the hypothesis that systemic use of aspirin, an inhibitor of platelet aggregation, affects the efficacy of PDT. METHODS: A retrospective review was conducted of data for patients treated with PDT at one institution between 2001 and 2004. End points included total number of PDT treatments, mean time between PDT treatments, change in visual acuity from baseline to 3 months after last PDT treatment, and concurrent or subsequent treatments other than PDT. RESULTS: A total of 244 eyes of 222 patients met inclusion criteria, of which 102 eyes from 92 patients were included in the aspirin taking group. Aspirin takers received an average of 3.11 PDT treatments compared with 2.39 PDT treatments for nonaspirin takers (P = 0.001). Decrease in logMAR visual acuity was greater for aspirin takers (P = 0.0003), and a loss of > or =3 lines was seen in 58% of aspirin takers compared with 35% of nonaspirin takers (P = 0.0003). These differences remained statistically significant after controlling for patient age, lesion type, and lesion size. CONCLUSIONS: Patients taking aspirin required more PDT treatments and had worse visual outcomes than patients not taking aspirin, possibly due to aspirin's ability to inhibit platelet aggregation and thereby diminish the efficacy of PDT.
Subject(s)
Aspirin/therapeutic use , Choroidal Neovascularization/drug therapy , Photochemotherapy , Photosensitizing Agents/therapeutic use , Platelet Aggregation Inhibitors/therapeutic use , Porphyrins/therapeutic use , Aged , Female , Humans , Male , Retreatment , Retrospective Studies , Verteporfin , Visual AcuityABSTRACT
A 76-year-old man developed a sudden painless superior field defect in the right eye, retinal whitening along the inferior temporal arcade, and fluorescein angiographic evidence of lobular choroidal non-perfusion. One week later, ophthalmoscopy revealed inferior optic nerve edema with splinter hemorrhages consistent with an anterior ischemic optic neuropathy (AION) and a new cholesterol plaque near the macula. There was no clinical, serologic, or pathologic evidence of giant cell arteritis. Carotid ultrasound revealed no evidence of significant stenosis but did show an echolucent soft plaque in the right carotid artery. Transthoracic echocardiography demonstrated normal left ventricular function with no source of emboli. The presumed cause of the clinical findings in this patient was embolism, a rarely reported cause of AION. An embolic origin may be considered in non-arteritic AION associated with choroidal non-perfusion.
Subject(s)
Choroid/blood supply , Embolism/complications , Infarction/etiology , Optic Nerve/blood supply , Optic Neuropathy, Ischemic/etiology , Retina , Aged , Diagnosis, Differential , Embolism/diagnosis , Fluorescein Angiography , Follow-Up Studies , Fundus Oculi , Humans , Infarction/diagnosis , Ischemia/diagnosis , Ischemia/etiology , Male , Optic Neuropathy, Ischemic/diagnosis , Visual FieldsABSTRACT
PURPOSE: Treatment of retinal and choroidal diseases may be influenced by overlying blood. We compared the penetration through blood of various laser wavelengths used in thermal photocoagulation, photodynamic therapy, and transpupillary thermotherapy. METHODS: Laser light of wavelengths 514 nm, 568 nm, 647 nm, 689 nm, and 810 nm was directed through normal saline (control), whole blood with a hematocrit of 40%, and serial dilutions of whole blood until a steady-state reading of laser power output was obtained. Laser power output was measured with an Orion Laser Power/Energy monitor (Ophir Optronics LTD). Laser power was measured in milliwatts and expressed as a percentage of control. RESULTS: Five hundred fourteen-nanometer and 568-nm laser wavelengths penetrated the least through all dilutions of blood tested (>60% attenuation through the highest dilution tested); 647-nm, 689-nm, and 810-nm laser wavelengths penetrated most effectively through blood but were still significantly attenuated ( approximately 46%, 49.6%, and 47.0% attenuation, respectively, at the highest dilution tested). CONCLUSIONS: The presence of hemorrhage may have a significant effect on the delivery of laser energy to underlying structures/tissue. This may affect parameters used in thermal and nonthermal laser treatment of ocular diseases such as choroidal neovascularization.
