A prospective, case controlled study of the natural history of diabetic retinopathy and maculopathy after uncomplicated phacoemulsification cataract surgery in patients with type 2 diabetes

Abstract

Aim: To determine if uncomplicated phacoemulsification cataract surgery is associated with an accelerated rate of progression of diabetic retinopathy or maculopathy postoperatively. Methods: A prospective trial of 50 type 2 diabetics undergoing monocular phacoemulsification cataract surgery by a single consultant surgeon. The grade of diabetic retinopathy and diabetic maculopathy in the operated and non-operated fellow eye was assessed preoperatively and for 12 months postoperatively. Results: Overall, retinopathy progression was observed in 11 patients. In seven the retinopathy progressed in both eyes, in three it progressed in the operated eye alone, and in one it progressed in the fellow eye alone. Macular oedema was observed in 13 eyes postoperatively. Four had transient pseudophakic cystoid macular oedema and nine true diabetic maculopathy. Where maculopathy progressed it did so symmetrically in five patients, it progressed in the operated eye alone in four patients, and the fellow eye alone in two patients. There was no significant difference in the number of operated and fellow eyes whose retinopathy or maculopathy progressed postoperatively. In both the operated (OE) and non-operated (NoE) eyes retinopathy progression was associated with a higher mean HbA 1 C (OE p=0.003; NoE p=0.001) and insulin treatment (OE p=0.008, NoE p=0.04). Conclusion: Uncomplicated phacoemulsification cataract surgery does not cause acceleration of diabetic retinopathy postoperatively and any progression that is observed probably represents the natural history of the disease. Although macular oedema is common after cataract surgery it may follow a benign course and in many patients the development of clinically significant macular oedema postoperatively probably represents natural disease progression rather than being a direct effect of surgery.

Changes in diabetic macular oedema after phacoemulsification surgery

“…In contrast, duration of diabetes, types of treatment, and the presence of hypertension or nephropathy were not related to the degree of macular oedema. Although previous studies did not find a significant correlation between haemoglobin A 1C and progression of macular oedema, 26,27 our quantitative study suggests that the percentage of haemoglobin A 1C present at the time of surgery may be a significant predictor for progression of macular oedema.…”

“…[24][25][26][27] Accordingly, these studies suggested that progression of diabetic macular oedema may be classified as follows: a transient pseudophakic macular oedema such as Irvine-Gass syndrome, or substantial progression of diabetic maculopathy. 24,25,27 Our study quantitatively confirmed these two types of macular oedema. That is, macular thickening generally occurs after cataract surgery, but this resolves with time in most diabetic patients.…”

“…[13][14][15][16]22,23 Similarly, diabetic macular oedema has been shown to worsen after cataract surgery, [24][25][26] although controversy remains as to the incidence of this worsening. 7,27 Some studies have shown that there are two types of worsening of macular oedema after surgery: transient pseudophakic oedema that spontaneously resolves such as Irvine-Gass syndrome [28][29][30] and actual progression of diabetic maculopathy. It has also been suggested that macular oedema tends to show actual worsening in eyes afflicted with DR at the time of cataract surgery.…”

Phacoemulsification with intravitreal triamcinolone in patients with cataract and coexisting diabetic macular oedema: a 6-month prospective pilot study

“…Squirrell et al 3 recently showed that uncomplicated phacoemulsification did not cause progression of diabetic retinopathy postoperatively and that any progression observed probably represents the natural history of the disease. 3 However, the presence of maculopathy at the time of surgery has been suggested to be a risk factor for poorer visual outcome and therefore some authors have recommended that cataract surgery be performed earlier in diabetics to avoid this risk. [4][5][6] If clinically significant macular oedema (CSMO) is identified before surgery, the Royal College of Ophthalmologists' guidelines for cataract surgery in diabetics state that it should be treated at least 12 weeks prior to surgery.…”

Diabetic retinopathy progression and visual outcome after phacoemulsification in South-Asian and Afro-Caribbean patients with diabetes

“…8 While some studies have described increased progression of diabetic retinopathy and maculopathy following phacoemulsification cataract surgery, others have not. [9][10][11] Recent studies have suggested differences in the prevalence of complications, including retinopathy between various races. 12, 13 Chowdhury and Lasker 12 in a study of 292 newly diagnosed early-onset type II diabetic patients, including 165 South-Asians, found a higher prevalence of macrovascular and microvascular disease including retinopathy and nephropathy in South-Asians.…”