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

The chronic cyclitis was first described under the designation of cyclitis by Ernst Fuchs in 1892, having been described as peripheral uveitis and pars planitis. The etiopathogenic nature of chronic cyclitis has been in controversy but the role of allergy is suggested in this disease entity, The inflammatory process starts at ciliary body and peripheral chorioretina, extends to anterior chamber and vitreous. It is incidious, bilateral and recurrent, affects young individuals. This condition begins with minimal symptoms of hazy vision and vitreous opacity, may result in serious visual disturbances due to various complications including cataract, macular degeneration, retinal detachment, glaucoma and phthisis bulbi. A 50 year old man was found to have chronic cyclitis in his left eye that was treated with antituberculous agents and sub-Tenon's injection of corticosteroid agent.
Anterior Chamber ; Cataract ; Ciliary Body ; Glaucoma ; Humans ; Hypersensitivity ; Macular Degeneration ; Middle Aged ; Pars Planitis ; Retinal Detachment ; Uveitis* ; Uveitis, Intermediate*

The optic canal begins to be formed by the fusion of two roots of the lesser wing of sphenoid. It is a funnel shaped tube measuring about 4~9 mm long and 4~6 mm broad. But the canal shows considerable variations in its caliber. The optic canal attains its full size at 3 and 5 years of age. Since the radiograms of the optic canal was taken in the living human subject first by Rhese (1911), various radiographic methods have been revised by many other scholars. The development of the radiographic technique made it possible not only to evaluate the morphology (size, shape and its symmetry) of the canal but also to find its pathology such as fracture, fissure, callus formation and abnormal shadow. In the radiogram of the optic foramen the most shows a quadrant of a circle in shape, being more or less elliptical, circular or quadrangular. The two principal diameters were measured: the A diameter, which is principal downward and outward at an angle, and the B diameter, which is at right angle to A (Goalwin, 1924). The average A diameter of normal adult optic foramen was reported to be 4.3 mm and the B 4.4 mm by Goalwin (1926, 1927). The average transverse diameter of normal optic foramen was said to be 5.5 mm by Harwood-Nash (1970). In Korea, normal Korean optic canal has never been surveyed roentgenologically. Theshape, size and symmetry of 312 normal optic foramen of 156 Korean were studied in the radiogram taken by Goalwin's method from January, 1974 to December, 1979. 1. The shape of the optic foramen was oval (42.4%), circular (28.4%), a quadrant of a circle (19.8%) and elliptical (9.4%). And 86% of the foramen showed symmetrical in shape. 2. The size of the optic foramen was as follows; A diameter is 4.73 mm (right), 4. 76mm (left); B diameter 5.00 mm (right), 5.06 mm (left); horizontal diameter 4.71 mm (right), 4.65 mm (left); vertical diameter 4.93 mm (right), 4.97 mm (left). Differnce between the diameters of the foramen measured by means of roentgenography and the actual diameter calculated by Goalwin's formula was 0.03~0.04 mm. 3. The diameter of optic foramen seemed to attain its full size at 5 years of age. The average size of each diameter before age 5 was shorter than that after age 5 by 0.44~0.96 mm (p<0.006). 4. There were no appreciable variations in size and shape depending on sex. 5. The optic foramen was same on the two sides (13.8%). Differences of 5% or less were noted in 41.8%; differences of 20% or less shown in 89.1%. 6. Differences between the diameters (A, B, vertical of the foramen of the right and that of the left were less in the symmetrical foramen than asymmetrical (p<0.04).
Adult ; Bony Callus ; Humans ; Korea ; Pathology ; Radiography

No abstract available.
Urodynamics*

The effect of the Nd:YAG laser on the rabbit retina was evaluated with fundus photography, light microscopy and transmission electron microscopy(TEM), and compared with the effect of the Argon laser. Fundus photography was performed at 2 days, 4 days, 7 days, 14 days, 29 days and 49 days after treatment. The enucleated retina was examined by light microscopy and TEM. In YAG treated eye, laser reaction was not found at 0.5mJ level but laser reaction(G2-3) was found at 1.5mJ level. Laser reaction(G3-4) with expulsive bleeding was found at 2.5 and 3.5mJ level. Bleeding was seemed to be originated from the choroidal layer. 2 days after treatment, hemorrhage was sustained but bleeding was not continued. 7 days after treatment, hemorrhage was completely absorbed. In Argon treated eye, photocoagulation burns was well formed without and bleeding. In pathologic examination of YAG treated eye, full thickness disruption of the retina amd Bruch's membrane and replacement of these layers with fibrous scar tissue were revealed at 2.5 and 3.5mJ level. In 1.5mJ energy level of the YAG laser and Argon laser irradiation, the outer half of the retina, RPE and Bruch's membrane appeared to be pridominantely affected than the inner half of the retina. The extent and character of his to pathology in Argon treated lesion was not so different from that of the YAG laser 1.5mJ lesion.
Argon ; Bruch Membrane ; Burns ; Choroid ; Cicatrix ; Hemorrhage ; Lasers, Solid-State ; Light Coagulation ; Microscopy ; Pathology ; Photography ; Retina*

Retinal pigment epithelial cells(RPE) from a monolayer on the outer portion of sensory retina and have important physiologic functions that include solute transport, phagocytiosis and digestion of membrances shed from photoreceptor outer segments, and drug detoxication. Recently, transplantation of normal RPE has been proposed as a potential therapeutic modality in the surgical management of subretinal neovascularization in age related macular degeneration(ARMD). The viability of RPE at the time of transplantation is important for a good result after transplantation. This viability can be influenced by the period and environmental conditions of storage after harvest.In this study, the influence of these two factors on the viability was evaluated under controlling other remaining factors in vitro. And limitation of masimal time and optimal environmental conditions of storage were investigated.From November 1997 to February 1998, RPE cell sheets from six donor eyeballs for corneal transplantation in the department of ophthalmology of Severance Hospital were harvested and stored in -70degrees C, 4degrees C, or room temperature condotion. The viability of RPE cells at 0, 24 and 48 hours after havest was assessed and compared statistically.The viability was highest at 4degrees C condition. During storage, the viability was about 95% at 24 hours for and decreased abruptly to below 90% at 48 hours. Therefore, RPE cells for transplantation are to be stored at 4degrees C condition and transplantation should be performed within 24 hours after harvest.
Corneal Transplantation ; Digestion ; Epithelial Cells* ; Humans* ; Macular Degeneration ; Ophthalmology ; Retina ; Retinaldehyde* ; Tissue Donors*

The complications of peripheral or posterioruveitis, such as vitreous opacity, epiretinal membrance, and tractional retinal detachment may need vitreous surgery. This study was undertaken to evaluate the efficacy of transpars plana vitrectomy in the case of epiretinal membrance or tractional retinal detachment secondary to chronic uveitis.We included 23 eyes of 21 patients, and among them there was 16 eyes of epiretinal membrance and 7 eyes of tractional retinal detachment respectively. Improvement of vision, 2 lines or more in Anellen Chart, was noted in 10 eyes(63%) for epiretinal membrance and 2 eyes(29%) for tractional retinal detachment within post-operative 1 month. Final visual acuity decrease, compared with preoperative vision, was noted in 4 eyes(25%) for epiretinal membrance and 6 eyes(86%) for tractional retinal detachment with a mean follow-up of 34 months. The most common cause of visual acuity decrease was recurrent or persistent inflammation and resultant fibrous tissue proliferation, which became obvious within post-operative 3 months.Therefore, we`re able to conclude that the main cause of postoperative visual acuity decrease is persistent intraocular inflammation and fibrous change. So it is necessary to remove posterior hyaloid membrance actively and combine with medical treatment like corticosteroid therapy in order to control the inflammation even after vitreous surgery.
Follow-Up Studies ; Humans ; Inflammation ; Retinal Detachment ; Traction ; Uveitis* ; Visual Acuity ; Vitrectomy*

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