Level of generalized microangiopathy in patients with isolated diabetic maculopathy (DMP) and patients with proliferative diabetic retinopathy (PDRP)
M. Opitz1, C. Moschner2, A. Vieregge2, M. Heide2, U. Schmidt-Erfurth1
Background: Diabetic microangiopathy induces two characteristic manifestations at the retina: Exudative vascular reactions within the macular area (DMP) or occlusive-ischemic mechanisms with formation of neovascularization within the mid and outer periphery (PDRP). PDRP is known to be tightly correlated with diabetic polyneuropathy (PNP) and is being judged as a symptom of advanced generalized microangiopathy. In DMP the level of systemic microvascular disease has not been evaluated.
Patients and method: A prospective study in patients with either isolated DMP or PDRP and long- standing diabetes was conducted. Retinal angiopathy was classified clinically and angiographically. The level of generalized microangiopathy was documented by grading of the level of PNP including clinical neurological examination, electroneuro- (ENG) and electromyography (EMG).
Results: The mean age of patients was 61,3 years in the DMP group (n=26) and 53,8 years in the PDRP group (n= 20). In 53,8% of patients with DMP and 70% of the PDRP patients both clinically and electrophysically (EMG/ENG) significant PNP was documented. Clinically both groups invariably demonstrated changes consistent with a distal-symmetrical type of PNP. Neurographically a pathologic reduction in nerve conduction velocity was regularly present as found by ENG, while signs of denervation by EMG were seen in 20% of DMP patients only, but 50% of PDRP patients.
Conclusion: The majority of patients with PDRP, but also half of all patients with isolated DMP demonstrate a significant PNP as result of a generalized microangiopathy. This observation indicates that also DMP patients carry a significant risk for systemic disease. Signs of chronic neurogenic decomposition by EMG were more frequent in PDRP consistent with a more advanced stage of angiopathy in this group.
1 University Eye Clinic Lübeck, Ratzeburger Allee 160, D-23538 Lübeck
2 University Neurology Clinic Lübeck, Ratzeburger Allee 160, D-23538 Lübeck