Search Results - "International Ophthalmology"

1573-2630

retinopathy of prematurity ; perfluorocarbon liquids ; retinal detachment

Springer Online Journal Archives 1860-2000

Medicine

Abstract Retinopathy of prematurity with retinal detachment continues to present a challenge to the vitreoretinal surgeon despite many advances in technique. We report on two eyes with stage 4 and 5 ROP operated on using vitrectomy techniques and a perfluorocarbon liquid (Vitreon®). The surgical technique is described in detail.

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1573-2630

retina ; macular ; detachment ; vitrectomy ; diabetic retinopathy

Springer Online Journal Archives 1860-2000

Medicine

Abstract Macular detachment due to peripheral retinal tears that occur after pars plana vitrectomy for proliferative diabetic retinopathy can result in severe visual loss despite successful retinal reattachment. The authors reviewed the records of three patients who developed peripheral sclerotomy-related rhegmatogenous retinal detachments one to six months after vitrectomy for proliferative diabetic retinopathy, despite the absence of detectable sclerotomyrelated retinal tears by indirect ophthalmoscopy and scleral depression at the conclusion of surgery. All three patients had received standard panretinal laser photocoagulation in a complete encircling pattern either prior to or during the initial vitrectomy. Clinically or echographically, each patient was seen to have a partial or complete annual peripheral sclerotomy-related rhegmatogenous retinal detachment delimited to the equator. In each of these three cases, posterior extension of the peripheral retinal detachment into the macular area was prevented by the most anterior row of the photocoagulation scars. Standard panretinal laser photocoagulation applied in a complete encircling pattern may be useful in the prophylaxis of macular detachment from sclerotomy-related retinal tears that occur after vitrectomy for proliferative diabetic retinopathy.

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1573-2630

Fuch's heterochromic cyclitis ; HLA-antigens ; uveitis

Springer Online Journal Archives 1860-2000

Medicine

Abstract Genetic typing of class I major histocompatibility complex (MHC) antigens (HLA-A, -B and -C) was performed in 22 patients with Fuch's heterochromic cyclitis (FHC) and in a control group of 339 healthy subjects in order to ascertain whether there are any genetic factors that protect against or increase the risk of developing this disease. The frequency of only one HLA-antigen was found to differ significantly in the patients with FHC as compared with the normal subjects: HLA-A2 had a negative association with FHC (9.09% in FHC versus 47.47% in the control group; p〈0.01, Fisher's exact test with correction for the number of antigens studied) with an odds ratio of 0.11 (95% confidence limits 0.03 and 0.50). Other HLA antigens also showed a negative or positive association with FHC but not to a statistically significant level. Our results suggest a possible role for HLA genetic factors in the pathogenesis of FHC.

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1573-2630

needle drainage ; pneumatic retinopexy ; retinal detachment ; subretinal fluid drainage

Springer Online Journal Archives 1860-2000

Medicine

Abstract Thirty bullous retinal detachments were treated with pneumatic retinopexy and drainage of subretinal fluid. Patient selection criteria were similar to pneumatic retinopexy. All the eyes were reattached after the first operation. In three (10%) eyes new breaks with retinal detachment developed within two months after the initial operation and were treated with scleral buckling. One of these three eyes developed proliferative vitreoretinopathy grade D3 two months after scleral buckling. Twenty-nine (96.7%) out of thirty eyes were eventually reattached. The follow-up period was at least nine months. Visual acuity was maintained or improved in 29 (96.7%) eyes. Complications developing due to subretinal fluid like extension of detachment, persistence of subretinal fluid, subretinal gas, reopened retinal breaks were not encountered. By applying cryotherapy to a reattached retina after drainage of subretinal fluid, retinal pigment epithelial dispersion is decreased and the so-called steamroller technique is avoided. Drainage of subretinal fluid did not prevent a good success rate and did not result in additional complications.

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1573-2630

excimer laser ; filtration ; photoablation ; pseudomembrane

Springer Online Journal Archives 1860-2000

Medicine

Abstract The purpose of this study was to verify the feasibility of ab externe layer-by-layer excimer laser photoablative removal of limbal tissue down to the trabecular meshwork and to assess the damage caused by this procedure to the neighbouring structures. Excimer laser photoablation (193 nm) can remove layers of corneal tissue effectively with little or no damage to the adjacent areas. Previous experimental studies have demonstrated a decrease in outflow resistance after ab-externo photoablative removal of juxtacanalicular tissue. We have performed ab-externo photoablative removal of limbal tissue overlying the trabecular meshwork in four freshly enucleated eyes from our Eye Bank. The beam of an excimer laser (wavelength 193 nm; fluence 180 mJ/Sq.cm) was shaped using a metal mask with a rectangular opening of 1.2×2.5 mm. After removing the conjunctiva, photoablation was carried out at maximum surgical microscope magnification (40 x) until trabecular meshwork appeared at the bottom of the crater. Light microscopy showed that craters had smooth walls and their base reached the Schlemm's canal area; all structures appeared of normal morphology. Transmission electron microscopy showed a thin layer of amorphous material or pseudomembrane on the side walls of the crater; corneoscleral collagen fibers were abruptly interrupted and undistorted. At the bottom of the crater the trabecular meshwork and Schlemm's canal tissues appeared normal.

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1573-2630

Springer Online Journal Archives 1860-2000

Medicine

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1573-2630

fluorometry ; non-enzymatic glycosylation ; photolysis ; spectrophotometry

Springer Online Journal Archives 1860-2000

Medicine

Abstract We have examined the effect of visible light and ultraviolet on the non-enzymatic glycosylation of lysine in vitro. Glucose and L-lysine were mixed and incubated under white light, UV-A, UV-B, or in the dark. During 15 days of incubation in the dark, a heterogeneous mixture of intensely brown chromophores developed, with a dominant fluorescence excitation maximum at 350 nm and emission maxima near 425 nm. The process was delayed or inhibited to a moderate extent by white light, whereas under UV-A and UV-B this effect was more pronounced. We conclude that non-enzymatic glycosylation can be photochemically modulated by both visible light and ultraviolet.

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1573-2630

ivermecin dose estimation ; weight ; height ; physical appearance ; Kaduna ; Nigeria

Springer Online Journal Archives 1860-2000

Medicine

Abstract Ivermectin is a safe and effective microfilaricide which has been shown to have a beneficial impact on some onchocercal eye lesions. Current requirements for the distribution of ivermectin are that patients be weighed, and that their dose be determined according to their weight. This requirement increases the cost of distributing the drug to communities in need of treatment and, when scales breakdown, may lead to the suspension of distribution. Data are presented on a simple, alternative method of dose assessment based on the physical appearance of the patient. Fifteen assessors achieved an overall level of agreement with the weight-based schedule of 86% on a sample of 6420 patients. The level of agreement varied between assessors, from 73% to 95%. About 6% of the population would have received doses outside the range of the current weight-based schedule. We believe that the current insistence that each individual's dose of ivermectin be determined by weighing will hamper efforts to distribute the drug to those most in need of it and that our data indicate that workers can be trained to distribute ivermectin safely without weighing every individual. We would welcome confirmation of our findings from other populations.

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1573-2630

corneal autofluorescence ; diabetes ; fluorophotometry ; retinopathy grade

Springer Online Journal Archives 1860-2000

Medicine

Abstract Corneal autofluorescence has been lately studied as a predictor of retinopathy severity in diabetic patients. We measured corneal autofluorescence in 138 eyes of 69 diabetic patients and 64 eyes of 32 healthy controls. Diabetic patients were subdivided by the severity of retinopathy according to the Modified Airlie House Classification (stage 1: no or minimal retinopathy; stage 2: minimal background retinopathy; stage 3: background retinopathy; stage 4: (pre-) proliferative retinopathy. The fluorescence peak value and the area underlying the corneal autofluorescence curve were measured with a scanning fluorophotometer (Fluorotron Master, Coherent Radiation Palo Alto CA) Healthy controls' values of corneal autofluorescence (peak value: mean 11.03±3.77 ng. equivalent fluorescein/ml; area: mean 163.85±61.40 scan-point × ng. equivalent fluorescein/ml) resulted similar (peak value: p=0.83; area: p=0.61) to those of diabetic patients without retinopathy (peak value: mean 11.2±3.4 ng.eq/ml; area: 170.07±57.23 scan-pnt.ng.eq/ml). A statistically significant difference was found between diabetic patients without retinopathy and patients with stage 2, 3, 4 retinopathy. No statistically significant difference was found both for the peak value (p=0.50) and for the area (p=0.61) between stage 3 and stage 4 retinopathy. The sensitivity and specificity of corneal autofluorescence as a screening test for diabetic retinopathy were 82% and 62% for the peak value, 87% and 60% for the area; the positive predictive value for the presence of diabetic retinopathy was 65% for the peak and 63% for the area.

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1573-2630

blood-aqueous barrier ; fluorophotometry ; acute anterior uveitis ; HLA B27

Springer Online Journal Archives 1860-2000

Medicine

Abstract The blood-aqueous barrier (BAB) permeability was studied by fluorophotometry in 17 healthy control subjects and in 27 eyes from 27 patients with HLA-B27-positive acute anterior uveitis (HLA-B27 AAU). Twenty of these patients had an associated spondyloarthropathy. BAB permeability was studied during the ocular inflammatory crisis and in the disease-free periods in the same patients. Anterior chamber fluorophotometric scans were performed before and 30 minutes after the intravenous injection of 14 mg/kg of sodium fluorescein. The diffusion coefficient (Kd) was obtained from the ratio between the fluorescein concentration in the anterior chamber and the NPBF. Data were analyzed using the Student's t test and analysis of variance. A statistically significant difference (P 〈 0.001) was found between the Kd of active HLA-B27 AAU (61.4±16.8×10−4 min−1) and the Kd of inactive HLA-B27 AAU (4.8±1.6×10−4 min−1). No statistically significant differences were found between the Kd of inactive HLA-B27 AAU and the Kd of the control subjects (4.3±1.0×10−4min−1). We also failed to detect significant differences between patients with and without spondyloarthropathy either during the acute attack or during the disease-free period. On the basis of these results we conclude that the permeability of the BAB remains intact in inactive HLA-B27-positive AAU. The parallel fluorophotometric behaviour of HLA-B27-positive AAU with spondyloarthropathy and without spondyloarthropathy suggests that both share a common pathogenetic mechanism.

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1573-2630

Springer Online Journal Archives 1860-2000

Medicine

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1573-2630

HLA antigens ; pars planitis

Springer Online Journal Archives 1860-2000

Medicine

Abstract The familial occurrence of pars planitis is rare. We have found ten cases reported previously. We describe a new case of pars planitis in a family. The affected members included a mother and two of her four children. The family was tested for HLA antigens in order to establish a comparison with others HLA types by different authors. We have not identified any cause for the familial occurrence of this disease. We discuss the role of genetic and ambiental factors.

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1573-2630

Springer Online Journal Archives 1860-2000

Medicine

Electronic Resource

1573-2630

cataract ; cataract surgery ; prevalence ; systemic diseases

Springer Online Journal Archives 1860-2000

Medicine

Abstract Age related cataract is the most common cause of blindness in the world. Most of these patients are elderly and are likely to have various associated systemic diseases. Higher mortality has been reported in patients undergoing cataract surgery. In order to determine the prevalence of associated systemic disease, we carried out a large eye camp based study in 6103 age related cataract patients. Seventeen percent of our patients had systemic problems. Pulmonary disease was seen in 4.3%, cardiovascular disease and hypertension in 4.1%, diabetes mellitus in 3.8%, skin disorder in 1.4%, orodental disease requiring tooth extraction in 3%, and other diseases were seen in 0.4% of the cases. Seventy eight patients (1.27%) had significant systemic complications post-operatively, 46% of whom required hospitalization in a tertiary care center. Thus, all patients undergoing cataract surgery should be evaluated for associated systemic diseases to prevent morbidity and mortality in the preoperative, operative and postoperative period.

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1573-2630

acid fast bacilli ; cold abscess ; fine needle aspiration cytology ; orbital tuberculosis

Springer Online Journal Archives 1860-2000

Medicine

Abstract Three cases of orbital tuberculosis are presented, two as cold abscess in the orbit and one as a chronic indolent sinus. A simple clinical test like Fine Needle Aspiration Cytology (FNAC) can demonstrate some or all of the characteristic pathological features like caseating necrosis, epitheloid cells and Langhan's giant cells. Important corroborative evidence can be obtained from the Tuberculin test and a positive therapeutic trial. While there are many other causes or orbital swelling and abscess, tuberculosis should be considered an important differential diagnosis in endemic areas. Simple tests like the tuberculin reaction and Fine Needle Aspiration Cytology should be considered among the routine diagnostic investigations for orbital swellings.

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1573-2630

acquired immunodeficiency syndrome ; AIDS ; progressive outer retinal necrosis syndrome ; retinitis ; varicella-zoster virus

Springer Online Journal Archives 1860-2000

Medicine

Abstract The progressive outer retinal necrosis (PORN) syndrome is a recently described clinical variant of necrotizing herpetic retinopathy in patients with the acquired immunodeficiency syndrome (AIDS). It is caused by varicellazoster virus infection of the retina. Its course and clinical features distinguish it from the acute retinal necrosis syndrome and CMV retinopathy. Early disease is characterized by multifocal deep retinal opacification. Lesions rapidly coalesce and progress to total retinal necrosis over a short period of time. Despite aggressive therapy with intravenous antivirial drugs, prognosis is poor; disease progression and/or recurrence is common, and the majority of patients develop no light perception vision. Total retinal detachments are common. Prophylaxis against retinal detachment using laser retinopexy has not been useful in most cases. PORN syndrome is an uncommon, but devastating complication of AIDS.

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1573-2630

Springer Online Journal Archives 1860-2000

Medicine

Electronic Resource

1573-2630

cataract ; diabetes ; fluorescence ; furosine ; glycation ; Scheimpflug-photography

Springer Online Journal Archives 1860-2000

Medicine

Abstract Glycated proteins formed by the Maillard reaction were measured by furosine determination in human normal lenses and in senile and diabetic cataracts. Furosine, an hydrolysis product of fructose-lysine adduct formed in the early stages of the Maillard reaction, was measured by high performance liquid chromatography (HPLC). Furosine levels in diabetic cataracts were found to be 3 to 4 times higher than those observed for senile cataracts. The increased glycation levels both in cortex and nucleus were related to the increase of fluorescence determined in vitro by fluorometry and in vivo by Scheimpflug photography. Lens proteins were incubated with glucose and it has been demonstrated that protein glycation occurred parallel with the increase in concentration of fluorescent chromophores that present similar characteristics as those observed in vivo. The results indicate that protein insolubilization seemed to involve preferentially glycated proteins and at least in diabetic cataracts, the process seems to be initiated in the cortical region.

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1573-2630

corneal autofluorescence ; diabetic retinopathy ; corneal endothelium cell count ; fluorophotometry

Springer Online Journal Archives 1860-2000

Medicine

Abstract We measured the corneal autofluorescence in groups with different levels of diabetic retinopathy severity (72 eyes of 46 patients) and in age-matched non-diabetic controls (34 eyes of 24 controls). We also estimated the corneal endothelium cell count and pachymetry with a contact specular microscope. For the controls, mean corneal autofluorescence was 8.8 ng equivalents fluorescein/ml (SD 0.3). Results showed increased autofluorescence of the cornea in diabetic patients (mean 17.9 ng equivalents fluorescein/ml, SD 4.2), related to the duration of diabetes (P 〈 0.05) and to the severity of diabetic retinopathy (P 〈 0.0001). Corneal endothelial cell count results showed no statistically significant relation to corneal autofluorescence (P 〈 0.6), indicating that the increased autofluorescence cannot be attributed to a change in corneal cell density.

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1573-2630

collagen-vascular disease ; delayed type hypersensitivity ; immunohistochemistry ; scleritis ; vasculitis

Springer Online Journal Archives 1860-2000

Medicine

Abstract Posterior scleritis can present with a variety of symptoms, and its clinical diagnosis is therefore difficult. Little is known about the pathogenesis and the cellular effector mechanisms. This case report presents the immunopathological findings of posterior scleritis in the enucleated eye of a 28-year-old female with no known underlying disease. The cells infiltrating the scierai fibers consisted predominantly of T cells. Many of them were CD4 cells. Clusters of T and B cells were found in perivascular areas. No signs of primary vasculitis were seen. The cellular infiltrate in posterior scleritis shows features compatible with a T-cell-mediated (autoimmune) disorder.

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