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Acipimox is a nicotinic acid-derived antilipolytic drug devoid of major side effects, and has been used in a number of human trials. This work reports the effects of Acipimox on leptin production from isolated rat adipocytes, in comparison with nicotinic acid and insulin. For cells isolated from normal animals, all these three reagents stimulated leptin release to a similar extent. Acipimox and nicotinic acid were more potent than insulin in stimulating leptin release from cells isolated from diabetic animals, probably because of impaired insulin sensitivity in cells from these diseased animals. Co-incubation of Acipimox with norepinephrine or dibutyryl cAMP diminished its stimulatory effects on leptin release, in parallel with increased lipolysis, suggesting that intracellular free fatty acids play an important role in mediating leptin production in adipocytes.

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PURPOSE: To evaluate the indication for endoscopic vitreoretinal surgery in proliferative diabetic retinopathy (PDR). METHODS: Chart review of consecutive cases of vitreoretinal surgery for PDR performed by one of the authors (Y.L.F.) over a 2-year period. RESULTS: Endoscopic vitreoretinal surgery was performed in 8 of 41 (19.5%) eyes. The surgical indications were small pupil (3), hyphema (3), pseudophakia with fibrotic posterior capsule (1), and pars plana neovascularization with anterior tractional retinal detachment (6). CONCLUSION: Endoscopic vitreoretinal surgery, by enhancing the visualization of the retroirideal space, is a useful technique in PDR with opaque ocular media and/or neovascularization of the pars plana and ciliary body.

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OBJECTIVE: To differentiate polypoidal choroidal vasculopathy (PCV) from central serous chorioretinopathy (CSC). DESIGN: A retrospective, observational case series. PARTICIPANTS: Thirteen patients originally diagnosed with CSC proved to have PCV after more extensive evaluation and follow-up. METHODS: A clinical and angiographic review of patients with manifestations of CSC, including macular detachment. MAIN OUTCOME MEASURES: Demographic data, funduscopic examination, and fluorescein and indocyanine green (ICG) angiographic findings. RESULTS: Thirteen patients initially suspected of having CSC were ultimately diagnosed as having PCV. These eyes had exudative macular detachments secondary to a small caliber, polypoidal choroidal vascular abnormality or so-called polypoidal choroidal neovascularization. The clinical manifestations in the fundus varied. They included multiple, variably sized serous pigment epithelial detachments, neurosensory retinal detachment, lipid deposition, patchy atrophy of the pigment epithelium and indistinct staining from decompensation of the posterior blood-retinal barrier on fluorescein angiography. In reality, the suspected PEDs proved to be polypoidal lesions of PCV when imaged with ICG angiography. CONCLUSIONS: The clinical diagnosis of CSC or PCV generally poses little challenge to the experienced retinal specialist. However, in CSC with persistent and/or recurrent exudation, a myriad of retinal pigment epithelial changes may evolve that make it difficult to differentiate these two entities. In such patients, ICG angiography is useful in differentiating CSC from PCV. An accurate clinical diagnosis is important since each of these entities, CSC and PCV, may differ in terms of their risk factors, natural course, and visual prognosis.

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PURPOSE: To characterize a newly discovered choroidal vascular abnormality in patients who have received radiation therapy for subfoveal choroidal neovascularization (CNV) secondary to age-related macular degeneration. DESIGN: Two-center cross-sectional study. PARTICIPANTS: In the United States, there were 95 patients who were treated with 10 or 12 Gy of external beam photons. In Belgium, 98 patients were treated with 20 Gy. These patients were examined retrospectively for the presence of a specific CNV abnormality. RESULTS: During the follow-up period, an unusual vascular growth pattern was identified in 12 patients (12.6%) of those treated in the United States and in 7 (7.1%) of those treated in Belgium. These patients developed round or oval vascular blebs along the outer border of their neovascular lesions. These blebs profusely leaked fluorescein dye and could be imaged best by indocyanine green angiography. Patients with these blebs appeared to have a marked propensity for loss of visual acuity. CONCLUSION: An unusual pattern of new vessel growth occurred in 19 of the 193 patients with CNV treated with radiation. This new entity, termed radiation-associated choroidal neovasculopathy, is a recognizable disorder that appears to have a particularly poor prognosis.

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PURPOSE: To determine systemic factors associated with central serous chorioretinopathy. METHODS: In a retrospective study, 230 consecutive patients with central serous chorioretinopathy examined in a referral setting were compared with a historical gender-matched and age-matched control group of 230 patients with ocular findings who were examined in the same referral setting. RESULTS: The median age of the patients was 49.8 years, and of the control subjects, 50.0 years. The male-female ratio for both groups was 2.7:1. Patients with central serous chorioretinopathy were more likely to use psychopharmacologic medications (odds ratio = 2.6; 95% confidence interval = 1.30 to 5.19; P = .0049) and corticosteroids (odds ratio = 3.17; 95% confidence interval = 1.30 to 7.70; P = .0067) and were more likely to have hypertension (odds ratio = 2.25; 95% confidence interval = 1.39 to 3.63; P = .0008) than were the control subjects. CONCLUSIONS: This study identified psychopharmacologic medication use, corticosteroid use, and hypertension as factors associated with central serous chorioretinopathy. These findings reinforce the concept that stress and adaptations to stress play a role in this disorder. The findings of possible associations between central serous chorioretinopathy and both hypertension and corticosteroid usage suggest that these modifiable factors may influence morbidity of central serous chorioretinopathy.

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Ophthalmic endoscopes allow examination of intraocular structures when traditional surgical microscopic visualization is limited or impossible. Periodic evaluation of the optical precision of these instruments is essential to ensure optimal intraoperative performance. A test card has been developed to aid in the calibration of ophthalmic endoscopes. Its 5 test targets assess white balance and fiberoptic bundle integrity, focus and resolution, orientation, color fidelity, and angle of view.

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BACKGROUND: Evaluation of the vasculature and blood flow in the fundus is limited by the small field of view of conventional fundus cameras. We sought to develop an easy method to image wide areas of the fundus. METHODS: Wide-angle contact fundus lenses with antireflective coatings in the infrared range were placed on the eye and indocyanine green angiography was done on the fundus through the contact lenses. More than 50 patients with varying fundus pathology have been examined. RESULTS: The angular field of view using this method can reach 160 degrees. Obtaining angiograms where the field of view extended anterior to the ora serrata was simplified, and studying the choroidal vasculature in detail was possible. In addition, imaging of entities such as peripheral choroidal neovascularization and choroidal tumors was enhanced with the present technique as compared with conventional techniques. CONCLUSIONS: Angiography through wide-angle fundus lenses is an easy and inexpensive method of visualizing large areas of the fundus. This technique may help improve our ability to image the angioarchitecture, hemodynamics, and pathologic changes in the retina and choroid.

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OBJECTIVE: This study aimed to determine the effect of external beam radiation therapy on choroidal neovascularization (CNV) secondary to age-related macular degeneration (AMD). DESIGN: The study design was a nonrandomized clinical trial with an historic control group. PARTICIPANTS: A total of 91 patients were treated with external beam radiation. These patients were compared retrospectively to the 119 patients in a control group. INTERVENTION: Patients with subfoveal CNV who did not meet the criteria for laser treatment defined by published reports from the Macular Photocoagulation Study Group or who did not want laser treatment were considered for radiation therapy in a nonrandomized, prospective clinical trial. Additional entry criteria for this prospective study included visual acuity better than or equal to 20/320 on the Early Treatment Diabetic Retinopathy Study chart and a lesion size less than 12 disc areas. The patients were treated with 5 fractions of 200 cGy 6 MV external beam photons. MAIN OUTCOME MEASURES: The visual acuity measured at baseline was compared to the visual acuity after 1 year of follow-up. RESULTS: The mean baseline visual acuity of the 91 patients entered into the Radiation Study was 20/80. After 1 year, 83 patients (91.2%) completed follow-up, and their mean visual acuity dropped to 20/200. By comparison, the mean baseline visual acuity of the control patients also was 20/80, and after 1 year, the control subjects had a mean visual acuity of 20/125. At 1 year of follow-up, 49.4% of patients treated with radiation and 38.1% of the control subjects lost 3 or more lines of visual acuity (P = 0.16). CONCLUSIONS: This study found that external beam radiation using 1000 cGy in 5 fractions, a dose similar to that used in previous studies, was not effective in the treatment of CNV secondary to AMD. These results suggest that patients should not be treated with this dose of external beam radiation for CNV secondary to AMD.

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PURPOSE: The purpose of the study is to investigate the demographic characteristics and clinical findings of central serous chorioretinopathy (CSC). METHODS: This study examined a consecutive series of 130 patients with CSC seen over an 18-month period. RESULTS: The mean age of the patients when examined was 51 years, and the male-to-female ratio was 2.6:1.0. A total of 62 patients were older than 50 years of age when first examined. Although the patients shared some clinical and angiographic similarities, the older patients had a lower mean visual acuity and were more likely to have diffuse retinal pigment epitheliopathy, bilateral involvement, and secondary choroidal neovascularization than were the younger patients. With ophthalmoscopic and angiographic examination results, it was possible to differentiate CSC in older adults from choroidal neovascularization. CONCLUSION: This study expands the clinical concept of CSC. The male-to-female ratio was much lower, and the range of ages of the patients was much greater than in previous studies. Disease manifestations in older adults differed somewhat from those seen in younger adults. In older patients, CSC can be distinguished from other exudative maculopathies, particularly that of choroidal neovascularization secondary to age-related macular degeneration.

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PURPOSE: The authors studied the indocyanine green (ICG) videoangiography findings of central serous chorioretinopathy (CSC) in older adults. BACKGROUND: Central serous chorioretinopathy in older adults may be confused with the exudative forms of age-related macular degeneration (AMD) because the two entities may have similar ophthalmoscopic and fluorescein angiographic findings. Because of its enhanced ability to image the choroidal circulation, ICG videoangiography has been used to describe certain choroidal vascular abnormalities in young adults with CSC, as well as older patients with choroidal neovascularization (CNV). The ICG videoangiography findings in CSC in older adults is largely unknown. METHODS: The authors performed ICG videoangiography on 36 patients aged 50 years or older with CSC to characterize their findings. RESULTS: The ICG videoangiography findings of the patients were consistent, revealing choroidal vascular hyperpermeability manifested by areas of hyperfluorescence that were first seen in the midphase of the angiogram. In the later phases of the angiogram, there were dispersion of the hyperfluorescence and a distinctive silhouetting of the larger choroidal vessels. CONCLUSIONS: Older patients with CSC have a unique temporal and topographic pattern of hyperpermeability that can help establish the proper diagnosis.

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A disposable 19-gauge ophthalmic endoscope has been developed for imaging and treatment during vitreoretinal surgery whenever standard microscopic visualization is limited or impossible. The endoscopic system is adaptable to many standard light sources and standard video imaging or storage equipment. Preliminary clinical experience has demonstrated the usefulness and practical application of this new instrument.

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BACKGROUND: The role of vitreoretinal traction in the macular region as a causative factor for the development of idiopathic macular holes is widely accepted. The purpose of this study is to provide a prospective evaluation of patients with idiopathic macular holes to determine the risk of hole formation in the fellow eye. METHODS: The authors performed a prospective study of 50 patients with unilateral idiopathic macular holes combining complete ocular examination, including slit-lamp biomicroscopy, with kinetic B-scan ultrasound evaluation of the status of the vitreoretinal interface. Natural history data were obtained by follow-up examinations performed at 3-month intervals throughout the course of the study. RESULTS: During a median follow-up of 33 months, a full-thickness macular hole developed in 1 (2%) of 46 normal fellow eyes. Full-thickness holes also developed in three (75%) of the four eyes that had premacular hole changes (stages 1A and 1B) in the fellow eye on initial examination. All macular holes in fellow eyes occurred within 24 months of entry into the study. Kinetic ultrasound evaluation determined that fellow eyes with separation of the posterior hyaloid membrane in the foveal region were protected from future macular hole development. Those patients with attachment of the posterior hyaloid membrane in both eyes were at highest risk of holes forming in the fellow eye. Patients with posterior hyaloid membrane separation in the macular hole eye only, with an attached vitreous in the fellow eye, were at intermediate risk. CONCLUSION: The authors suggest that fellow eyes in patients with unilateral idiopathic macular holes have a relatively favorable natural history and that kinetic ultrasound examination may help determine which of these fellow eyes is at highest risk for full-thickness macular holes developing.

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The evaluation of the posterior vitreoretinal interface is important in the study of the natural course and preoperative evaluation of numerous disorders of the retina. The exact status of the posterior vitreous cannot always be reliably determined by ophthalmoscopic examination. The diagnostic value of kinetic contact ultrasonography was investigated to evaluate the status of the posterior vitreous in 70 eyes with clear ocular media. Contact B-scan ultrasound provided an extremely accurate method for evaluating the posterior vitreoretinal interface in 69 of the 70 eyes in this study, when compared with all conventional clinical means of examination including slit-lamp biomicroscopy with the Goldmann contact lens and fundus photography with the El Bayadi-Kajiura lens. Contact B-scan ultrasonography is an important diagnostic adjunct in determining the status of the vitreoretinal interface.

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A series of young adult patients developed solar retinopathy during sun exposure over a two-day period in a particular region of the United States during March of 1986. Evaluation of the photobiological and geophysical parameters involved in solar retinitis are presented. A multifactorial pathogenesis is proposed. Of interest, a possible increase in terrestrial ultraviolet B radiation secondary to a localized relatively low ozone column during the days involved may have contributed to the retinal damage. Recommendations for protection from solar retinitis are noted.

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Seventy-six consecutive patients with total rhegmatogenous retinal detachments and severe proliferative vitreoretinopathy underwent combined pars plana vitrectomy, lensectomy, panretinal photocoagulation, perfluoropropane gas (C3F8)/fluid exchange, and scleral buckling. Sixty-two (82%) of the patients had successful, sustained (greater than 12 months) posterior retinal reattachments at last examination. Of these 62 patients, 40 (65%) had complete retinal attachment, with no evidence of regrowth of periretinal membranes or redetachments following the initial procedure. In the remaining 22 cases with successful reattachment of the retina posterior to the equator, partial peripheral retinal detachments were observed. In 16 of the 22 cases, the detachments occurred entirely anterior to the boundary of the previously placed photocoagulation lesions. The posterior retina remained uninvolved, and no further treatment was needed. Reoperation was required in the other six patients to achieve sustained posterior retinal reattachment. Postoperative visual acuity ranged from 20/40 to bare light perception, with 69% of the anatomically successful cases obtaining functional visual acuity (greater than 20/400). Failures were related to reproliferation of fibrous membranes.

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