Adhesive forces between the retina and the retinal pigment epithelium, which is mainta ined by active mechanisms unique for living animals, deteriorates rapidly after death and leads to spontaneous retinal detachment. Change of retinal adhesiveness in rabbits after death was investigated using a new method. Retinal detachment was induced by applying various levels of aspiration power from 0 to 1OO mmHg to the vitreous cavity using a vitrectomy instrument immediately after the rabbit was killed without enucleation. And the time required for creating the retinal detachment was measured. Retinal adhesiveness deteriorated and spontaneous retinal detachment occurred 28 minutes and 35 seconds after death confirming the active adhesion between the retina and the retinal pigment epithelium before death Increase of aspiration power led to shortening of time required for creating retinal detachment. From aspiration powers of 0 to 100 mmHg, the common logarithm of time required for retinal detachment was inversely proportional to the aspiration power [IogY = 1.45215 - 0.01113X, (R2=0.99041), X: aspiration power (mmHg), Y: time required for creating retinal detachment (minutes)]. Thus, presumed time of retinal detachment could be estimated between the aspiration powers of 0 to 100 mmHg.
Adhesiveness ; Adhesives* ; Animals ; Postmortem Changes* ; Rabbits ; Retina* ; Retinal Detachment ; Retinal Pigment Epithelium* ; Retinaldehyde* ; Vitrectomy

Posterior instability of the shoulder is far less common than anterior or multidirectional instability. There is still controversy in the diagnosis and treatment of recurrent posterior instability, and many treatment protocols have been advocated. However the failure rate as high as 50% was reported. The purpose of this study is to introduce characteristic physical findings of posterior instability, to present our operative techniques, and to report the efficacy of a superior shift of the postero-inferior capsule in the treatment of recurrent posterior instability. From June 1995 to September 1996, five patients, six shoulders underwent postero-inferior capsular shift for posterior instahility and were evaluated at an average of 17 months(ranged from 9 to 26 months) after operation. The average age was 22.4 years. Preoperatively, mean scores of pain, stability and function according to American Shoulder and Elbow Society (ASES) scoring system were 21, 9, and 16 points respectively and mean overall ASES score was 46 points. After surgery, the average range of motion was 175 of forward elevation and 74 of external rotation and internai rotation in back was up to the sixth thoracic level. Postoperative mean scores of pain, stability and function were 29, 34 and 25 points respectively and mean overall ASES score was 88.5 points. No patient had a recurrence of posterior instability. All patients had satisfactory results with significant improvement in stability and function except one case who had multidirectional instability that mainly involved the posterior component
Clinical Protocols ; Diagnosis ; Elbow ; Humans ; Range of Motion, Articular ; Recurrence ; Shoulder*

The early ultrastructural changes of basement membrane thickening and degeneration of the pericyte were noted in retinal capillaries in diabetic patients. However no early ultrastructural changes were reported in diabetic iris capillary. The authors studied the ultrastructural features of basement membrane of iris capillaries which were obtained during cataract surgery in five diabetic patients and compared with those obtained in five nondiabetic patients. The endothelium basal lamina, pericyte basal lamina and membrane-like pericyte matrix in didabetic iris capillaries were thicker than those in nondiabetic Iris capillaries. The thickening of pericyte basal lamina is more prominant than the endothelium basal lamina in diabetes. The duration of diabetes had no relationship to endothelium basal lamina but, showed statistically significant relationship to thickness of pericyte bascal lamina and pericyte matrix.
Basement Membrane* ; Capillaries* ; Cataract ; Endothelium ; Humans ; Iris* ; Pericytes ; Retinaldehyde

PURPOSE: Optic disc harmatoma is usually seen in tuberous sclerosis patients, but, it may be seen in otherwise normal people. Visual acuity is usually not affected by this lesion. METHODS: We experienced a 40-year-old woman with optic disc hamartoma who presented with acute visual defect. With oral triamcinolone 48mg/day, her visions recovered to normal in 2 weeks. RESULTS: Her age, symptom, and course of disease supported the diagnosis of optic neuritis. CONCLUSION: We report this patient as a case of optic disc hamartoma combined with optic neuritis.
Adult ; Diagnosis ; Female ; Hamartoma* ; Humans ; Optic Neuritis* ; Triamcinolone ; Tuberous Sclerosis ; Visual Acuity

Despite the progress in the treament of the subretinal neovascular membrane(SRNVM) by the development of laser photocoagulation, it has been reported difficult to manage with laser photocoagu1ation on which developed in high myopic eyes: first, their location in relation to the foveola is usually difficult to discriminate; second, subretinal neovascular m6mbrane developes very close to the foveola; third, the atrophic photocoagulation scar may extend to the foveola. The interferone alpha 2a has been known to suppress angiogenetic activity, and its application to subretinal neovascular membrane in high myopia has been suggested. The effect of interferon alpha 2a on neovascular membrane in high myopia was investigated by the authors. Subjects included 16 eyes with interferon treament and 12 eyes as control who had been followed for 3 months or longer. The median total dose in these patients was 75 X 10(6) units, given over a six- to eight-week period. In the interferon treament group, the activity of neovascular membrane decreased in 9 eyes(56%) and the visual acuity improved in 7 eyes(44%). In contrast, the control group showed a sustained activity of neovascular membrane and the visual acuity was improved in only one eye(6%). Therefore, interferon alpha 2a can be considered as an alternative method in the management of the some subretinal neovascualr membrane in high myopia which is resistant to the other treament.
Cicatrix ; Humans ; Interferon-alpha* ; Interferons* ; Light Coagulation ; Membranes* ; Myopia* ; Retinaldehyde* ; Visual Acuity

Despite the progress in the treament of the subretinal neovascular membrane(SRNVM) by the development of laser photocoagulation, it has been reported difficult to manage with laser photocoagu1ation on which developed in high myopic eyes: first, their location in relation to the foveola is usually difficult to discriminate; second, subretinal neovascular m6mbrane developes very close to the foveola; third, the atrophic photocoagulation scar may extend to the foveola. The interferone alpha 2a has been known to suppress angiogenetic activity, and its application to subretinal neovascular membrane in high myopia has been suggested. The effect of interferon alpha 2a on neovascular membrane in high myopia was investigated by the authors. Subjects included 16 eyes with interferon treament and 12 eyes as control who had been followed for 3 months or longer. The median total dose in these patients was 75 X 10(6) units, given over a six- to eight-week period. In the interferon treament group, the activity of neovascular membrane decreased in 9 eyes(56%) and the visual acuity improved in 7 eyes(44%). In contrast, the control group showed a sustained activity of neovascular membrane and the visual acuity was improved in only one eye(6%). Therefore, interferon alpha 2a can be considered as an alternative method in the management of the some subretinal neovascualr membrane in high myopia which is resistant to the other treament.
Cicatrix ; Humans ; Interferon-alpha* ; Interferons* ; Light Coagulation ; Membranes* ; Myopia* ; Retinaldehyde* ; Visual Acuity

Tangential vitreoretinal traction around fovea is known to be the principal cause in the pathogenesis of idiopathic macular holes. According to the recent study, the internal limiting membrane(ILM) may provide a scaffold for fibroblast proliferation and contraction, therefore play an important role in the enlargement of macular hole. We removed the ILM during macular hole surgery and assessed the anatomical and functional outcome of the macular hole surgery. Twelve consecutive patients with full-thickness macular hole were enrolled in this study. They were examed for best-corrected vision, fundus photography, fluorescein angiography, Humphrey automated perimetry, focal eletroretinogram, before and after surgery. After surgery, vision was improved in 8 eyes(67%), hole was closed in 10 eyes(83%). Macular thresholds on visual field was increased in 8 eyes and peripheral scotomas developed in 3 eyes postoperatively. The amplitude increased in 7 eyes and the implicit time decreased in 8 eyes on focal electroretinograms postoperatively. Out results suggested that the complete removal of ILM should be attempted to improve vision and to close holes during the full-thickness macular hole surgery.
Fibroblasts ; Fluorescein Angiography ; Humans ; Membranes* ; Photography ; Retinal Perforations* ; Scotoma ; Traction ; Visual Field Tests ; Visual Fields

We experienced a case of D3 proliferative vitreoretinopathy complicated with a shortened retina in a 31-year-old male which was managed using 360-degrees circumferential retinotomy technique and a case of D1 proliferative vitreoretinopathy complicated with a shortened retina in a 26-year-old female which was managed using 260-degrees circumferential retinotomy technique. We report these cases with a review of the literature
Adult ; Female ; Humans ; Male ; Retina* ; Vitreoretinopathy, Proliferative

PURPOSE: To evaluate the pre-operative and the intra-operative factors including marginal fibrosis affecting the result of vitrectomy for macular hole. METHODS: The medical records of the patient who had been operated for idiopathic full-thickness macular hole from January 1997 to July 2000 were investigated retrospectively. RESULTS: Hole closure, as the implication of anatomical success, was seen in 28 eyes (84.8%) at 1 month after surgery and 23 eyes (69.7%) at the end of follow-up period. And the improvement of two or more Snellen line, as the implication of functional success, was seen in 17 eyes (51.5%). The smaller size of the hole was well correlated with higher rate of anatomical success (P=0.001). And there was a good correlation of higher anatomic success rate with the lack of marginal fibrosis around the hole (P=0.001). CONCLUSIONS: There must be more efforts and investigations on proper management of marginal fibrosis, which might help to improve the result of macular hole surgery.
Fibrosis* ; Follow-Up Studies ; Humans ; Medical Records ; Retinal Perforations* ; Retrospective Studies ; Vitrectomy

Pneumatic retinopexy is a new procedure that is effective in treating the uncomplicated cases of rhegmatogenous retinal detachments. The procedure of pneumatic retinopexy is composed of cryotherapy(photocoagulation), intraocular gas injection and postoperative positioning. The advantages of this procedure are less tissue damage, no hospitalization, reduced expense and minimal complication. For these reasons, this procedure has become popular retinal detachment surgeons. Peports of associated complications are still limited. The authors experienced one case of choroidal detachment after intraocular gas(SF6 gas) injection in rhegmatogenous retinal detachment in pseudophakic eye.
Choroid* ; Hospitalization ; Retinal Detachment