Robert C. Ramsay

Photocoagulation Treatment of Proliferative Diabetic Retinopathy: The Second Report of Diabetic Retinopathy Study Findings

Data from the Diabetic Retinopathy Study (DRS) show that photocoagulad inhibited the progression of retinopathy. These beneficial effects were noted to some degree in all those stages of diabetic retinopathy which were included in the Study. Some deleterious effects of treatment were also found, including losses of visual acuity and constriction of peripheral visual field. The risk of these harmful effects was considered acceptable in eyes with retinopathy in the moderate or severe retinopathy in the moderate or severe proliferative stage when the risk of severe visual loss without treatment was great. In early proliferative or severe nonproliferative retinopathy, when the risk of severe visual loss without treatment was less, the risks of harmful treatment effects assumed greater importance. In these earlier stages, DRS findings have not led to a clear choice between prompt treatment and deferral of treatment unless and until progression to a more severe stage occurs.

Progression of Diabetic Retinopathy after Pancreas Transplantation for Insulin-Dependent Diabetes Mellitus

We studied the effect of successful pancreas transplantation and consequent normoglycemia (mean total hemoglobin A1, 7.0 percent; range, 5.8 to 8.3) on visual function and diabetic retinopathy in 22 patients with Type I diabetes mellitus (study group). Sixteen similar patients in whom pancreas transplantation had been unsuccessful (mean total hemoglobin A1, 12.0 percent; range, 8.0 to 18.0) served as a control group. The majority of patients in both groups had advanced proliferative retinopathy. At a mean follow-up of 24 months we found no significant difference between the groups in the rate of progression of retinopathy, expressed as a score. Success of the transplantation did not prevent progression of retinopathy across the range of retinopathy studied. Progressive retinopathy was observed more commonly in patients with low retinopathy scores (nonproliferative or mild proliferative retinopathy) at base line in both the study group (13 of 17 eyes, or 76 percent) and the control group (7 of 12 eyes, or 58 percent). Further analysis suggested the possibility that after three years of euglycemia, the study group had less deterioration than the control group, particularly in eyes with advanced retinopathy. We observed no difference in the rate of loss of vision between the two groups. This study provides evidence that pancreas transplantation and subsequent normoglycemia neither reverse nor prevent the progression of diabetic retinopathy.

Treatment of Cytomegalovirus Retinitis with Intravitreal Ganciclovir: Long-term Results

Long-term management of cytomegalovirus (CMV) retinitis by intravitreal injection of ganciclovir was evaluated in ten patients with acquired immune deficiency syndrome (AIDS). Patients were unable to tolerate systemic ganciclovir because of severe neutropenia (8 cases), catheter-induced sepsis (1 case), or the need to continue therapy for human immunodeficiency virus (HIV) with zidovudine (ZDV) (1 case). All patients had a favorable response to initial treatment. Cytomegalovirus retinitis progressed in four fellow eyes in which treatment was deferred. Vision improved or remained stable in all but one eye. Patients were followed for a mean of 4 months and received an average of 16.6 intravitreal injections in each eye. Relapse occurred late in the course while on maintenance treatment in five eyes (33%). There was no evidence of toxicity from repeated intravitreal injections. Treatment was very well tolerated. The only severe complication in a total of 249 injections was a single case of Staphylococcus epidermidis endophthalmitis which responded to intravitreal antibiotic treatment. Intravitreal ganciclovir is an effective alternative to systemic ganciclovir in those patients with severe neutropenia and in those patients who desire to remain on systemic ZDV.

Ocular Perforation Following Retrobulbar Anesthesia for Retinal Detachment Surgery

We encountered three examples of the perforation of the globe by the retrobulbar needle in a series of 4,000 patients who had undergone retinal reattachment surgery with local anesthesia. The presence of significant myopia was a contributing factor in all three cases. We managed the perforation site through the detached retina with cryopexy and external tamponade, and we treated perforations through the attached retinas either with cryopexy at surgery or photocoagulation postoperatively.

A 10-year experience with 290 pancreas transplants at a single institution

Since our report at the 1984 American Surgical Association meeting of 100 pancreas transplants from 1966 through 1983, another 190 have been performed. The current series, begun in 1978, now numbers 276 cases, and includes 133 nonuremic recipients of pancreas transplants alone (PTA), 46 simultaneous pancreas/kidney transplants (SPK), and 97 pancreas tranplants after a kidney transplant (PAK). Duct management techniques used were free intraperitoneal drainage in 44 cases, duct occlusion in 44, enteric drainage in 89, and bladder drainage in 128. The 1-year patient and graft survival rates in the entire cohort of 276 were 91% and 42%. One-year patient survival rates were 88% in the first 100, 91% in the second 100, and 92% in the last 76 cases; corresponding 1-year graft survival rates were 28%, 47%, and 56% (p less than 0.05). A prospective comparison of bladder drainage (n = 82) versus enteric drainage (n = 46) in PAK/PTA cases since November 1, 1984 favored bladder drainage (1-year graft survival rates of 52% vs. 41%) because of urinary amylase monitoring. The best results were in recipients of primary SPK bladder-drained transplants (n = 39), with a 1-year pancreas graft survival rate of 75%, kidney graft survival rate of 80%, and patient survival rate of 95%. Logistic regression analysis, with 1-year graft function as the independent variable, showed significant (p less than 0.05) predictors of success (odds ratio) to be technique: bladder drainage (5.8) versus enteric drainage (2.5) versus duct injection (1.0); category: SPK (6.0) versus PAK from same donor (3.2) versus PAK from different donor (1.2) versus PTA (1.0); and donor HLA DR mismatch: 0 (5.0) versus 1 (2.5) versus 2 (1.0) antigens. On April 1, 1989, 90 patients had functioning grafts (60 euglycemic and insulin-free for more than 1 year, 10 for 5 to 10 years); these, along with 24 others whose grafts functioned for 1 to 6 years before failing, are part of an expanding cohort in whom the influence of inducing a euglycemic state on pre-existing secondary complications of diabetes is being studied. Only preliminary data is available. In regard to neuropathy, at more than 1 year after transplant in patients with functioning grafts, conduction velocities in some nerves were increased over baseline. In regard to retinopathy, deterioration in grade occurred in approximately 30% of the recipients by 3 years, whether the graft functioned continuously or failed early, but thereafter retinopathy in the patients with functioning grafts remained stable.(ABSTRACT TRUNCATED AT 400 WORDS)

Ten Year Experience With Renal Transplantation in Juvenile Onset Diabetics

Between 1968 and 1978, 305 juvenile onset diabetic patients with uremia and 462 nondiabetic uremic patients of similar age received primary renal allografts at the University of Minnesota. Two hundred eight of the diabetic patients are alive and 190 have functioning renal grafts three months to ten years after transplantation. Cumulative patient survival rates at two years for diabetic recipients of kidneys from HLA identical siblings, other related and cadaver donors are 90, 73 and 68%, respectively; the corresponding graft functional survival rates are 90, 67 and 55%. For nondiabetic patients receiving kidneys from the same donor categories the corresponding patient survival rates are 97, 86 and 75%, while the graft functional survival rates are 94, 77 and 64%. The differences in patient and graft survival between diabetic and nondiabetic recipients are statistically significant only for the patients receiving grafts from HLA-nonidentical related donors. For all recipients under the age of 30, there are no statistically significant differences in patient and graft survival. Regardless of the age of the patient or the source of the kidney, the survival of diabetic patients treated with transplantation at our institution is better than the use of chronic hemodialysis, alone. Technical complications do not occur more frequently in diabetic transplant recipients. Cardiovascular disease is responsible for most of the late deaths in these diabetic patients. Amputations of digits or extremities have been required in 15% of the diabetic patients. On the positive side, the vision of 88% of these recipients remained stable or had improved visual acuity, and 82% of the diabetic patients were actively rehabilitated after transplantation. Kidney transplantation is the treatment of choice for end-stage renal failure in diabetic patients, just as it is for most uremic patients.

Diabetic macular edema associated with glitazone use.

Purpose: To describe diabetic macular edema (DME) in patients who developed fluid retention as a consequence of glitazone use. Methods: A chart review identified 30 patients who used pioglitazone or rosiglitazone and had both lower extremity edema and macular edema. Clinical reports, photographs, and fluorescein angiograms were reviewed. Patients followed for >3 months were analyzed separately. Results: Seventeen patients took oral pioglitazone, 11 took rosiglitazone, and 2 took both drugs at different times. Eleven patients were observed for >3 months after cessation of glitazones. Mean weight gain during drug administration in this group was 30 lb, and mean weight loss after drug discontinuation was 19 lb. Rapid reduction in macular edema off drug occurred in only 4 of 11 patients, but 8 of 11 had reduced edema over 2 years. Mean visual acuity in this group at the initial visit was 20/60, and at the final visit, it was 20/85. Four eyes of three patients had resolution of diffuse macular edema with improved vision after cessation of glitazones without laser treatment. Conclusions: Fluid retention occurs in 5% to 15% of patients taking glitazones. In some of these patients, glitazone use appears to be a cause of macular edema, and drug cessation appears to result in rapid resolution of both peripheral and macular edema. Fluid retention associated with glitazone use should be considered when assessing treatment options for patients with DME, especially those with concomitant peripheral edema.

Timing of vitrectomy for active proliferative diabetic retinopathy.

Eyes with active proliferative diabetic retinopathy with dense sub-hyaloid hemorrhage and significant visual loss represent an appropriate indication for prompt vitrectomy. Twenty-six such eyes in 22 patients were operated. The results are compared to 49 diabetic eyes undergoing vitrectomy for other complications of diabetic retinopathy. The results demonstrated both an improved anatomic success rate (85% compared to 73%) and a higher rate of reading visual function (54% compared to 18%) in the early vitrectomy group, substantiating the study hypothesis.

Histocompatibility Antigen Frequencies in Diabetic Retinopathy

We studied the histocompatibility antigens A and B in 300 insulin-dependent diabetics: 200 had proliferative retinopathy and 100 did not. The two groups were matched for known duration of diabetes and other clinical features. In both groups the frequencies of HLA-B8, HLA-B18, and HLA-B8/HLA-B15 were significantly higher, and those of HLA-B7 and HLA-B12 were significantly lower than in healthy controls. The patients with proliferative retinopathy were significantly less often positive for HLA-B7 (X2 = 10.0; Pc < .03) than patients with nonproliferative retinopathy. When both groups were stratified for age at diagnosis, there were additional differences. HLA-B15 was significantly more frequent in the proliferative retinopathy group with age at diagnosis between 15 and 40 years (nonproliferative retinopathy = 16.4%; proliferative retinopathy = 39.4%; X2 = 7.89, Pc < .03; relative risk = 3.32) and HLA-B7 significantly less frequent (nonproliferative retinopathy = 23.6%; proliferative retinopathy = 5.6%; X2 = 8.0, Pc < .03; relative risk = 0.19). These differences in histocompatibility frequencies between patients with and without proliferative retinopathy indicate a genetic contribution to diabetic retinopathy.

Vitrectomy for Double Penetrating Ocular Injuries

During the five-year period from 1977 to 1982, 15 consecutive patients with double penetrating ocular injuries were treated at the University of Minnesota. The 13 males and two females ranged in age from 5 to 38 years. Four patients had bilateral involvement. Vitrectomy techniques were used to stabilize the eyes and prevent or treat retinal detachment in 18 eyes. One eye was enucleated. Anatomic success was achieved in 11 eyes and visual success (visual acuity of 5/200 or better) in ten eyes. Surgical success was related to initial visual acuity, extent of vitreous hemorrhage, and the ability of the surgeon to excise completely the vitreous from the circumference of the exit wound.