How Prevalent is a Taut Thickened Posterior Hyaloid? Clinical and OCT Evaluation of the Posterior Hyaloid in Patients with Persistent Diffuse Diabetic Macular Oedema

Abstract

Abstract: : Purpose:A clinically evident taut thickened posterior hyaloid (TTPH) and OCT posterior hyaloidal traction (PHT) have both been suggested to be associated with good outcome from vitrectomy for diabetic macular oedema. A Medline search reveals 200 cases of vitrectomy for diabetic macular oedema of which 112 (56%) had a TTPH. This study aimed to determine prospectively the prevalence of a TTPH and PHT in diabetics with diffuse macular oedema that had failed to respond to laser. Methods:Diabetic patients with persistent diffuse macular oedema following one or more argon grid laser treatments were prospectively examined for clinical features of a TTPH. Optical Coherence Tomography(OCT) was performed looking for a traction macular detachment and posterior hyaloid vitreo retinal traction (PHT). These tests were performed as part of a routine evaluation of patients for inclusion in a randomised trial of vitrectomy versus more laser in patients with diabetic macular oedema Results:A clinically taut thickened posterior hyaloid was observed in 2/76 patients i.e.2.6% (95% CI 0-6.6%). 7/76 i.e. 9.2% (95% CI 3.2-15.2%) showed a traction macular detachment and posterior hyaloidal vitreo macular traction on OCT. PHT was present in the 2 patients with a clinical TTPH. Conclusion:Both TTPH and PHT were less prevalent than expected.

Keywords: 388 diabetic retinopathy • 628 vitreoretinal surgery • 354 clinical (human) or epidemiologic studies: prevalence/incidence