Prevalence and significance of retinopathy in subjects with type 1 diabetes of less than 5 years' duration screened for the diabetes control and complications trial.

OBJECTIVE: The Diabetes Control and Complications Trial (DCCT) demonstrated the powerlul impact of glycemic control on the progression of diabetic retinopathy. A large number of individuals (2,771) underwent stereoscopic color photography and fluorescein angiography as part of screening for participation in the DCCT. A subgroup of those individuals screened participated in the DCCT and underwent evaluation of their retinal vasculature semiannually for 4-9 years. These data were evaluated to determine how the 2000 American Diabetes Association position statement would apply to the DCCT experience. Specifically, the position statement indicates that the first dilated eye examination should be performed after 3-5 years' duration of diabetes because vision-threatening retinopathy virtually never develops in patients with type 1 diabetes during that interval RESEARCH DESIGN AND METHODS: We examined the experience of the DCCT in evaluating retinal photographs in 1,613 patients with type 1 diabetes of <5 years' duration and follow-up photographs every 6 months for 4-9 years in 855 members of that group. RESULTS: Of 1,613 subjects with type 1 diabetes of <5 years' duration screened for the DCCT, 716 (44.4%) had stereo-color photographic evidence of diabetic retinopathy, and 6 had preproliferative or worse pathology. Fluorescein angiography revealed retinopathy in 158 of 713 subjects with no evidence of retinopathy on color photographs. Thus, 874 (54.2%) of the original 1,613 subjects had retinopathy at baseline. DCCT follow-up identified 341 additional individuals in whom retinopathy was developing before 5 years; 1,083 of 1,613 (67.1%) individuals screened for the DCCT had retinopathy before 5 years' duration of diabetes. Those with retinopathy before 5 years had more rapid three-step progression of vascular pathology than those with no retinopathy. CONCLUSIONS: Dilated eye examinations and retinal photography should be included in the routine management of type 1 diabetes during the first 5 years to identify the individuals at greatest risk for vision-threatening problems.

Retinal fold in macula following intraocular gas. An avoidable complication of retinal detachment surgery.

Liquid vitreous was replaced with air during a scleral buckle for a superotemporal retinal detachment. After surgery, the patient was positioned so that air rolled over the detached retina from anterior to posterior, pressing a fishmouthed tear against the buckle that resulted in reattachment. After the air was absorbed, a large retinal fold was seen in the superotemporal macula along the former posterior margin of the detachment. If the patient had been positioned so that air rolled over the detached retina from posterior to anterior, the potentially visually destructive posterior retinal fold could have been avoided.

Mycobacterium chelonae conjunctivitis and scleritis following vitrectomy.

The atypical, or nontuberculous, mycobacteria are opportunistic pathogens that usually cause infection following accidental trauma or surgery. These organisms are ubiquitous in nature but have been found with increasing frequency in other environments that include medical offices and surgical suites. Management of atypical mycobacterial ocular infections can be difficult because in vitro antibiotic activity does not always correlate with in vivo efficacy and because normal immune defenses against mycobacteria may work too slowly to prevent irreversible damage to infected ocular tissues. This report describes a patient who developed a severe ocular infection due to Mycobacterium chelonae after vitrectomy. Despite eradication of the infection, the eye became blind and painful. Arch Ophthalmol. 2000;118:1125-1128

Acute pressure elevation following panretinal photocoagulation.

Intraocular pressure increased in 17 of 18 eyes treated for diabetic retinopathy with argon laser panretinal photocoagulation. All eyes had open anterior chamber angles before treatment. Fifteen eyes, continued to have open angles when first examined after treatment. The pressure elevation in these eyes averaged about 10 mm Hg, was detected soon after laser treatment, and persisted for several hours. Outflow facility usually was reduced. Three eyes had closed angles and elevated pressures when first examined after treatment. I addition, in five eyes that initially had open angles, angle closure developed later. Thus, the pressure elevation after extensive retinal photocoagulation usually begins with an open angle mechanism, but later may be due to angle closure as well. The reason for the pressure rise with an open angle is unknown.

Diabetic rubeosis and panretinal photocoagulation.

Iris fluorescein angiography was used to perform the first prospective, controlled, masked evaluation of the effect of panretinal photocoagulation on diabetic rubeosis. Eyes with rubeosis had iris fluorescein angiograms five to seven weeks apart. Eyes either had laser treatment immediately after the first angiogram or had no laser treatment between angiograms. The rubeosis was said to have improved if all three masked readers independently selected the angiogram performed last as having the less severe rubeosis. In eyes with severe rubeosis, only two of 11 (18%) spontaneously improved whereas 11 of 15 (73%) improved following laser therapy. In eyes with mild rubeosis, one of ten improved spontaneously and one of ten improved following laser therapy. Iris fluorescein angiography documented regression of severe but not mild rubeosis following panretinal photocoagulation.

Evaluation of microbiological diagnostic techniques in postoperative endophthalmitis in the Endophthalmitis Vitrectomy Study.

OBJECTIVE: To analyze the data for cultures and Gram stains prospectively collected by protocol in the Endophthalmitis Vitrectomy Study. DESIGN: Cultures of aqueous, undiluted vitreous, and (for patients who underwent vitrectomy) vitrectomy cassette fluid obtained from 420 patients were prepared on chocolate agar, in thioglycolate broth, and on Sabouraud dextrose agar; Gram stains of the aqueous and undiluted vitreous were made. Criteria were devised to distinguish true pathogens (confirmed positive cultures) from contaminants. SETTING: Private and university-based retina-vitreous practices and corresponding microbiology laboratories. RESULTS: Compared with the aqueous, undiluted vitreous produced a higher percentage of confirmed positive cultures and higher colony counts on chocolate agar and was more frequently the only source of a positive culture from the eye. Nevertheless, the aqueous and vitrectomy cassette fluid were the only source of a positive culture from the eye in 4.2% and 8.9% of eyes, respectively. The overall yields of chocolate agar and thioglycolate broth were similar. A positive Gram stain from the aqueous or undiluted vitreous was highly predictive of a positive culture from the eye, but a negative Gram stain had little predictive value for the culture result. The overall rate of laboratory-confirmed infection was not statistically significantly higher in the vitrectomy group than in the tap or biopsy group. CONCLUSIONS: The vitreous was a richer source of positive cultures and high colony counts than was the aqueous, either because it is more supportive of bacterial growth or because a somewhat larger inoculum of the vitreous than of aqueous could be obtained. The result of Gram stain should not determine the choice of antibiotic drugs in the treatment of endophthalmitis. Vitrectomy, with culture of the vitrectomy cassette fluid, did not produce significantly more positive cultures than tap or biopsy material, and the procedure should not be performed to improve the microbiological yield.

Optic disc edema in juvenile-onset diabetes.

The clinical and photographic records of patients with juvenile-onset diabetes and nonneurologic disc edema were reviewed to determine the natural history of the disease. Six female and two male patients, 14 to 40 years old, who had had diabetes for seven to 22 years had no visual complaints or mild blurring. All had 6/9 or better visual acuity and normal blood pressure. Visual fields were normal or showed an enlarged blind spot. The edematous discs had superficial, dilated, radially oriented, fluorescein-incontinent capillaries. Two patients had simultaneous neovascularization of the disc. Three received laser photocoagulation, and five received no therapy. In the seven followed up for six months or more, the edema resolved, resulting in 6/6 visual acuity. These findings suggest the edema resulted from a reversible vasculopathy that, due to few symptoms, may be more common than is presently appreciated.

Exogenous bacterial endophthalmitis treated without systemic antibiotics.

We treated 16 patients (16 eyes) with culture-proven exogenous bacterial endophthalmitis with intravitreal and subconjunctival antibiotics but without systemic antibiotics. After one to two sets of intravitreal injections, intraocular inflammation abated in all patients. After further surgery in four patients, all 16 eyes had clear media and attached retinas. Fifteen eyes attained a visual acuity of 20/400 or better; 12 eyes achieved 20/80 or better.

'Blow-outs' in the retinal pigment epithelium.

A hole was detected in the epithelium of a retinal pigment epithelium (RPE) detachment in two patients. Leakage through the hole led to an elevation of the overlying neurosensory retina in each case. The resulting vision was 20/70 in one eye and 20/30 in the other. The defects in the RPE occurred in a setting different from that usually seen with tears in the pigment epithelium and had a different clinical appearance.

Diabetic vitrectomy.

Diabetic vitrectomy is usually performed to remove vitreous blood or to relieve traction of the macula. In addition to removing vitreous opacities and severing all anteroposterior connections of the posterior hyaloid face with a cutting and sucking probe, tangential traction in and around the macula is eliminated by sectioning preretinal membranes with intraocular scissors. Complications are significant in terms of both their incidence and their consequences. They include choroidal or subretinal infusion, peripheral and posterior retinal breaks, intraoperative bleeding, and neovascular glaucoma. Proper management can minimize the occurrence and adverse effects of these complications. If prognostic factors are favorable, visual improvement occurs in 78 to 59% of eyes postoperatively. Preoperative iris neovascularization, florid proliferative diabetic retinopathy, long-standing detachment of the macula, and iatrogenic retinal breaks are all correlated with significantly lower success rates. Three independent studies have shown that if visual improvement is present 6 months postoperatively, the results are usually long-standing [2, 8, 20].