text: Purpose: : Quantitative and regional measurement of retinal blood flow in rodents is of prime interest for the investigation of regulatory mechanisms of ocular circulation in physiological and pathological conditions. In this study, a new quantitative autoradiographic method using N-isopropyl-p-14C-iodoamphetamine ([14C]-IMP), a diffusible radioactive tracer, was evaluated for its ability to detect changes in retinal blood perfusion during hypercapnia. Findings were compared to cerebral blood flow values measured simultaneously.
  Methods: : Hypercapnia was induced in awake Wistar rats by inhalation of 5% or 8% CO2 in medical air. Five minutes later, 100 µCi/kg [14C]-IMP was injected in the femoral vein within 30s. Two minutes later, the brain was frozen, the eyes were enucleated and both retinas were dissected out. One retina was digested and the amount of total radioactivity was determined with a scintillation counter. The other retina was whole-mounted on a glass slide and exposed with 20-micron thick brain sections on X-ray film for the quantification of regional changes in four retinal quadrants (nasal, temporal, superior and inferior) with computerized analysis (MCID basic 7.0).
  Results: : Retinal and cerebral blood flow were significantly increased under hypercapnic conditions. Autoradiographic analysis showed that retinal blood flow increased in every quadrants examined by 23 to 42%.
  Conclusions: : These results showed that hypercapnia-induced increase in retinal blood flow can be quantified using [14C]-IMP autoradiographic method and compared with brain changes. Therefore, this technique is a powerful tool to study how retinal blood flow is regulated in different regions of the rat retina.
  Abstract: : Purpose:To evaluate the clinical and histopathologic features of two cases of surgically resected ciliochoroidal melanomas. Methods:Clinical features of two patients with ciliochoroidal melanoma were reviewed. The resection specimens were processed routinely for histologic examination with the anterior, posterior, deep and lateral margins of resection evaluated for the presence of melanoma. Subsequent enucleation specimens were processed and evaluated for the presence of melanoma. Results:In the first case, the tumor microscopically extended to the anterior and lateral margins of resection. The blind, painful eye was enucleated and failed to exhibit melanoma. In the second case, the melanoma was transected and the posterior margin was frankly positive for melanoma. The eye was enucleated for residual tumor, and a 3 x 2 nodule of melanoma was present. Conclusion:There are two types of positive surgical margins of excision for uveal melanoma; microscopic and transected tumor. Observation with or without local adjuvant therapy is recommended for the former, and local adjuvant therapy or enucleation is recommended for the latter.
  Abstract: : Purpose:To investigate the effect of cataract surgery on the results of FDT perimetry. Methods:Subjects who were scheduled to undergo cataract surgery were prospectively identifed. Subjects underwent FDT perimetry in both eyes using the C-20 full threshold algorithm. Visual field testing was performed within one month before, and within three months after cataract surgery. The eye that did not undergo surgery served as a control. Results:49 eyes of 49 patients were included in this study. A mean improvement in mean deviation (MD) of 4.15 dB (P<.0001) was observed in the eyes that underwent cataract surgery. A mean improvement in MD of 1.33 dB (P=.13) was observed in the control eyes. The mean improvement in MD attributable to cataract surgery (improvement in surgical eye - improvement in control eye) was 2.82 dB (P<.008). Conclusion:Cataract removal does result in an improvement in the MD using FDT perimetry.