Cataract surgery and YAG-laser capsulotomy following vitrectomy for diabetic retinopathy

The present study was initiated to assess time-course and risk factors for the development of cataract and posterior-capsule opacification as well as complications of cataract surgery and YAG-laser capsulotomy following vitrectomy for diabetic retinopathy. The charts of all patients undergoing vitrectomy for diabetic retinopathy during a 5-year period in a university eye hospital were retrospectively reviewed. The course of 306 consecutive eyes in which the lens was retained during vitrectomy was analyzed for subsequent cataract surgery and YAG-laser capsulotomy. The first 6 months after cataract or YAG-laser surgery were examined for the occurrence of complications. Data were analyzed with regard to the time course using Kaplan-Meier life-table analysis. The proportion of eyes that underwent cataract surgery after vitrectomy increased nearly linearly with time, approaching 75% after 5 years. Silicone tamponade (relative risk 1.9; P = 0.0005) and transscleral retinal cryotherapy (relative risk 1.4; P = 0.003) were risk factors for subsequent cataract surgery. No significant cataractogenous effect of intravitreal gas as compared with balanced salt solution was found. YAG-laser capsulotomy was performed in 60% of vitrectomized diabetic eyes within 2 years but in only 10% of nondiabetic controls (P < 0.0001). Within 6 months of extracapsular cataract surgery with implantation of an intraocular lens (IOL) in 54 eyes, no serious complication was observed. After YAG-laser capsulotomy, vitreous hemorrhage occurred within 6 months in 6 of 21 eyes. In conclusion, cataract surgery was performed in 75% of the phakic eyes within 5 years of vitrectomy for diabetic retinopathy. Posterior capsular opacification is particularly common in this subset of eyes. No serious complication was observed after extracapsular cataract surgery with IOL implantation, but YAG-laser capsulotomy was associated with an increased risk for vitreous hemorrhage.     

Full panretinal photocoagulation and early vitrectomy improve prognosis of florid diabetic retinopathy

BACKGROUND: Florid diabetic retinopathy (FDR) is a rare form of proliferative diabetic retinopathy (PDR) that is characterized by a bilateral rapidly progressive, very severe ischemic retinopathy. Florid diabetic retinopathy was reported to carry a high risk of blindness. This study was conducted to determine whether visual prognosis of FDR can be improved by appropriate photocoagulation and surgical management. METHODS: The authors retrospectively studied 20 patients (40 eyes) who were treated from October 1978 to February 1994. Systemic risk factors, visual acuity, complete ocular examination, and fundus findings, as well as fluorescein angiography, were analyzed with respect to photocoagulation and surgical management. Mean follow-up was 3.6 years. RESULTS: All patients had poorly controlled type I diabetes (mean duration, 13.5 years), which often was associated with systemic complications. Mean initial visual acuity was equal to or better than 20/40 in 32 eyes (80%). During the course of the study, high-risk PDR was observed in 38 eyes (95%) and vitreous hemorrhage occurred in 26 eyes (65%). Extensive full subconfluent panretinal photocoagulation was performed completely in 37 eyes (92.5%). Vitrectomy was necessary in 15 eyes (37.5%). Macular edema was present in 30 eyes (75%). Major complications included retinal detachment that required surgery (2 eyes, 5%) and neovascular glaucoma (2 eyes, 5%). However, final visual acuity was equal to or better than 20/40 in 23 eyes (57.5%) and less than 5/200 in only 4 eyes (10%). CONCLUSION: These results suggest that aggressive treatment of FDR with extensive panretinal photocoagulation and early vitrectomy, when necessary, may result in a much better prognosis than has been reported previously.     

The Wisconsin Epidemiologic Study of diabetic retinopathy. XIV. Ten-year incidence and progression of diabetic retinopathy

OBJECTIVE: To examine the 10-year incidence and progression of diabetic retinopathy. DESIGN: Population-based incidence study. PARTICIPANTS: Seven hundred sixty-five insulin-taking diabetic persons diagnosed before age 30 years, 251 insulin-taking diabetic persons diagnosed at age 30 years or older, and 282 non-insulin-taking diabetic persons diagnosed at age 30 years or older who participated in baseline, 4-year, and 10-year follow-up examinations. MAIN OUTCOME MEASURES: The 10-year incidence of any retinopathy, progression of retinopathy, and progression to proliferative retinopathy were detected by masked grading of stereoscopic color fundus photographs using the modified Airlie House classification and the Early Treatment Diabetic Retinopathy Study severity scheme. RESULTS: The 10-year incidence of retinopathy (89%, 79%, and 67%), progression of retinopathy (76%, 69%, and 53%), and progression to proliferative retinopathy (30%, 24%, and 10%) were highest in the group diagnosed before age 30 years, intermediate in the insulin-taking group diagnosed at age 30 years or older, and lowest in the non-insulin-taking group, respectively. Increased risk of proliferative retinopathy was associated with more severe retinopathy at baseline. CONCLUSIONS: These data suggest relatively high 10-year rates of incidence and progression of retinopathy, and despite changes in the treatment of diabetes, there has been little change in the incidence and progression of diabetic retinopathy during the 10-year study period.     

The epidemiology of diabetes mellitus and diabetic retinopathy

The paper presents the results of examining the hydrodynamics of artificial heart valves (AHVs) manufactured in Russia and foreign countries. All the AHVs under study have been used in clinical practice for over 10 years and they are different in design. The hydrodynamics of AHVs was examined under static and pulsating flow through the valve. Photochromic imaging (PCI) was used for flow imaging. PCI is based on preparation of simulating blood (model physiological solution) in the medium, colour labels under laser radiation. The recording of colour label movement in the flow behind the valve using a speed camera makes it possible to follow flow hydrodynamics behind AHVs. The advantage of PCI over other methods is that the instant structure of flow behind the valve can be recorded just in the same section at any moment of an operating cycle. Based on the experimental data obtained by PCI, a procedure for comparative analysis of the hydrodynamic characteristics of AHVs was developed.     

Combined pars plana vitrectomy, lens removal and intraocular lens implantation for complications of diabetic retinopathy. Surgical results in 120 cases

We performed combined vitrectomy, lens removal and posterior chamber intraocular lens implantation for proliferative diabetic retinopathy in 120 eyes of 101 patients. Follow-up periods ranged from 3 to 63 months, with a mean of 17 months. Three lens removal methods were used: extracapsular cataract extraction (14 eyes), phacoemulsification and aspiration (49 eyes), and pars plana phacoemulsification (57 eyes). Preoperative rubeosis iridis or neovascular glaucoma was found in 21 eyes. Gas or temporary silicone oil tamponade was employed in 32 eyes. Surgical results were good, and the postoperative vision was finger counts or below only in 13 eyes. Thus the combined surgery proved to have no serious problems. Our results indicate two important points. (1) It is best to chose either of the following two methods for the lens surgery: phacoemulsification with continuous circular capsulorhexis, self sealing sclerocorneal incision, and in-the-bag fixation of the posterior chamber lens, or pars plana phacoemulsification leaving the anterior capsule, rub off and aspirating the lens epithelial cells, continuous circular capsulorhexis, and posterior chamber lens implantation in front of the anterior capsule from a self-sealing sclerocorneal wound. (2) It is mandatory to do complete vitrectomy and cut out the vitreous gels incarcerated in the sclerotomy site.     

Ophthalmologic management of diabetic retinopathy

Changes in lung mechanics were measured in asthmatic adults before and after a 10-day course of daily and a three-week course of alternate day adrenocortical steroid therapy. All patients improved after the 10 days of therapy. This response continued during the a.m. measurements on the alternate day regimen with further improvement through the afternoon of the treatment day. In the afternoon of the day off corticosteroid therapy there was a deterioration in flow rates.     

Screening for diabetic retinopathy. Initiation and frequency

A screening program for diabetic eye disease was established in Iceland in 1980. Diabetics involved in the screening program have a low prevalence of blindness, 1% in type 1 and 1.6% in type 2. We examined ways to make the screening program more efficient by identifying subgroups at low risk of developing eye disease that require treatment and therefore need less frequent screening. We studied whether diabetic eye disease screening programs may be trimmed by excluding children and examining diabetics without retinopathy biannually. Our results indicate that diabetic children under the age of 12 years do not need regular screening for eye disease. Biannual examinations seem to suffice in type 1 and 2 diabetic patients without retinopathy. However, in a setting where the eye clinic is located apart from the diabetes clinics, biannual examinations present practical problems which could result in a less effective screening for diabetic eye disease.     

Vitrectomy for traction macular detachment in diabetic retinopathy

BACKGROUND: A small number of eyes with proliferative diabetic retinopathy develop massive central fibrovascular membranes characterized by vitreoretinal tractions along the arcades and optic disk and retinal traction lines extending through the macula. The aim of our study was first to present the results of vitrectomy for removal of these central membranes and second to determine the correlation between preoperative parameters and postoperative visual outcome. SUBJECTS AND METHODS: We treated 28 eyes with severe central fibrovascular diabetic membranes by a modified bi-manual en bloc excision technique during vitrectomy. Preoperative examination included general status, visual acuity, slit-lamp investigation, binocular funduscopy, ultrasound investigation and visual evoked potentials (VEP). Further, we analyzed intraoperative complications and postoperative anatomic and functional outcomes. RESULTS: The retinas of 27 eyes with central traction retinal detachments were reattached by surgery. With a minimum of 6 months' follow-up, the macula remained attached in 24 eyes, while the retinas were completely attached in 22 eyes. Preoperative visual acuity was defective light perception to 0.1; an increase in visual acuity to maximal 0.1 was seen in 50% of the patients postoperatively. Preoperative visual acuity of light perception was associated with no functional improvement. Preoperative ultrasound investigation gave information about the real anatomic situation of the retina, especially if funduscopy was not possible. The other preoperative parameters could not predict correctly the functional outcome of vitrectomy in diabetics with severe central fibrovascular membranes because of the damage of the optic nerve and the retina. CONCLUSIONS: The high rate of anatomical reattachment after vitrectomy in diabetic eyes with severe central fibrovascular membranes is associated with a slight improvement of function; only preoperative visual acuity of hand motions or better was associated with an improvement of function.     

Secretion of GH and diabetic retinopathy

Recently it has been studied a possible pathogenetic role of GH in diabetic angiopathy. The purpose of the present study was to verify whether the diabetic retinopathy is associated or not with a high plasma GH level. In an attempt to answer this question we did the dosage of plasma GH after a oral glucose load (110 g), Insulin (0,1 U/Kg) i.v., and arginin i.v. (25 g/30'). The plasma GH measurements were approximately the same as in normal patients. The Authors underline the importance of GH in pathophysiology of diabetic angiopathy and report all recent literature on this argument.     

Vascular endothelial growth factor and severity of nonproliferative diabetic retinopathy mediate retinal hemodynamics in vivo: a potential role for vascular endothelial growth factor in the progression of nonproliferative diabetic retinopathy

PURPOSE: To determine the effect of vascular endothelial growth factor and retinopathy level on retinal hemodynamics in nondiabetic and diabetic rats and to evaluate retinal hemodynamics in nondiabetic and diabetic patients. METHODS: Forty-eight diabetic and 22 nondiabetic patients had their diabetic retinopathy levels determined from fundus photographs according to Early Treatment Diabetic Retinopathy Study (ETDRS). Fluorescein angiograms were recorded from the left eye by video fluorescein angiography. Retinal blood flow was calculated from the digitized angiograms. Human recombinant vascular endothelial growth factor or vehicle alone was injected intravitreally into 13 nondiabetic and 11 diabetic rats. RESULTS: Retinal blood flow decreased 33% in patients with ETDRS retinopathy level 10 compared with control patients (P = .001) and increased sequentially in more advanced stages of retinopathy, with a strong correlation between retinal blood flow and retinopathy level (r2 = 0.434, P = .001). In the diabetic rats, retinal blood flow was decreased 35.6% (P = .01). Vascular endothelial growth factor maximally increased retinal blood flow by 36.1% in nondiabetic rats after 25 minutes (P = .001) and by 73.7% in diabetic rats after only 5 minutes (P = .01) and caused a greater response in diabetic than in nondiabetic rats. CONCLUSIONS: Retinal blood flow increases with advancing nonproliferative diabetic retinopathy in humans, and diabetes accentuates the vascular endothelial growth factor-induced increase in retinal blood flow and venous dilation in rats. Vascular endothelial growth factor may contribute to the changes in retinal hemodynamics and morphology observed in early diabetic retinopathy.     

On the role of the posterior hyaloid membrane in the pathogenesis of and surgery for proliferative diabetic retinopathy

A total of 278 patients subjected to transciliary vitrectomy for proliferative diabetic retinopathy (PDR) were followed up. Thirty preparations of epiretinal membranes removed in surgery were examined under an optic microscope. Vessels newly forming in PDR were found to grow mainly along the external surface of the posterior hyaloid membrane; they ceased their growth after its removal. The posterior hyaloid membrane is the anatomical object of surgical intervention of PDR. The proliferative form of diabetic retinopathy is never seen in the presence of a naturally occurring or vitrectomy-induced complete posterior hyaloid detachment, that is why if the posterior hyaloid membrane is well detached from the retina in the course of operation, panretinal laser coagulation in the postoperative period is not recommended.     

The association of femal hormones with blindness from diabetic retinopathy

The rates of blindness from diabetic retinopathy with or without other causes for persons in the Model Reporting Area (14 states) were determined in five-year intervals by sex. Diabetic males younger than 45 years of age had a higher rate of diabetic blindness than females under 45 years of age. However, for ages 45 and older, the risks of blindness among diabetics were approximately equal for men and women. These data were consistent with the hypothesis that the presence of female hormones improves the prognosis in diabetic retinopathy.