Retinopathy in Patients with Diabetic Ophthalmoplegia Lucas Trigler, MD, 1 R. Michael Siatkowski, MD, 1,2 Angela S. Oster, MD, 2 William J. Feuer, MS, 2 Chad L. Betts, MD, 1 Joel S. Glaser, MD, 2 Norman J. Schatz, MD, 2 Bradley K. Farris, MD, 1 Harry W. Flynn, MD 2 Purpose: To review the clinical characteristics, prevalence, and severity of retinopathy in diabetics with cranial nerve (CN) 3, 4, and/or 6 palsies, and to determine the relationship between type and duration of diabetes mellitus (DM), presence of retinopathy, and occurrence of CN palsy. Design: Retrospective, comparative cohort study. Participants: Chart reviews of 2229 patients with CN 3, 4, and/or 6 palsies were performed at the Bascom Palmer Eye Institute (BPEI) from January 1991 through December 1997 and at the Dean A. McGee Eye Institute (DMEI) from January 1994 through July 2001. A total of 306 patients qualified for the study group. The Wisconsin Epidemiologic Study of Diabetic Retinopathy (WESDR) was used as a control. Methods: Demographic and clinical data were extracted to determine characteristics of patients with diabetic ophthalmoplegia. The subsets of data regarding type of DM and level of diabetic retinopathy in the study population were compared with the WESDR control data for statistical analysis. Main Outcome Measures: The prevalence of diabetic retinopathy in patients with diabetic ophthalmoplegia. Results: Of 2229 patients at both institutions with ocular motor CN palsy, 306 (13.7%) were associated with DM. The frequency of CN involvement was 6 (50.0%), 3 (43.3%), and 4 (6.7%). There was a total of 12 patients (3.9%) with consecutive palsies and 8 patients (2.6%) with simultaneous palsies (5 unilateral and 3 bilateral). At both institutions, the prevalence of retinopathy controlling for duration of DM was lower in both insulin-dependent DM (IDDM) and non-IDDM (NIDDM) type II diabetics as compared with controls (BPEI, P = 0.009 and P = 0.005; DMEI, P = 0.004 and P = 0.29). When data from both locations were combined, the difference was even more significant (IDDM, P = 0.001 and NIDDM, P = 0.006). There were no significant differences between the two institutions in gender, type or duration of DM, age at presentation, or frequency of CN involvement. Conclusions: Diabetic ophthalmoplegia most commonly involves CN 3 and 6, with relative sparing of CN 4. Multiple cranial nerves are affected simultaneously in 2.6% of cases, and consecutive palsies occurred in 3.9% of cases. Type II diabetics with ocular motor CN palsy have significantly less diabetic retinopathy than do controls. This may imply a different pathophysiologic mechanism for these two microvascular complications of DM. Ophthalmology 2003;110:1545–1550 © 2003 by the American Academy of Ophthalmology. Dysfunction of the ocular motor nerves in patients with microvascular disease is a common cause of acquired di- plopia. 1 Most of these cases are attributable to underlying systemic vascular diseases such as diabetes mellitus (DM) or hypertension. One report calculates that the incidence of CN palsy in diabetics is 5 to 10 times higher than in nondiabetics. 2 Because both diabetic ophthalmoplegia and diabetic retinopathy result from disturbances of normal mi- crovascular function, intuition suggests that the prevalence of each should be directly proportional. However, to our knowledge there are no large studies directly evaluating this relationship. In fact, it has long been the clinical impression of one of the authors (RMS) that retinopathy in patients with diabetic CN palsy is frequently mild or absent, despite often long-term or poorly controlled systemic disease. The purpose of this study was to evaluate the demo- graphic and clinical characteristics of patients with diabetic ophthalmoplegia, as well as to determine the prevalence of diabetic retinopathy in those with ocular motor nerve palsy. Additionally, we sought to determine if the type, duration, or severity of diabetes was associated with paresis of the third, fourth, and/or sixth cranial nerves. Material and Methods After appropriate Institutional Review Board approval at both institutions, a retrospective chart review of patients diagnosed with Originally received: July 12, 2002. Accepted: January 31, 2003. Manuscript no. 220465. 1 Dean A. McGee Eye Institute, Department of Ophthalmology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma. 2 Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami School of Medicine, Miami, Florida. Presented in past as a poster at the 28th annual meeting of the North American Neuro-Ophthalmology Society, Copper Mountain, Colorado, February 2002. Supported in part by an unrestricted grant from Research to Prevent Blindness, New York, New York (LT, RMS, BKF). Correspondence to R. Michael Siatkowski, MD, Dean A. McGee Eye Institute, 608 Stanton L. Young Blvd., Oklahoma City, OK 73104. 1545 © 2003 by the American Academy of Ophthalmology ISSN 0161-6420/03/$–see front matter Published by Elsevier Inc. doi:10.1016/S0161-6420(03)00542-6