The present study was conducted in 202 eyes of 202 diabetic patients with mature cataract who were willing to undergo cataract surgery attending out patient Department of Ophthalmology, at HIMS Hassan.
In our study, we found out of 202 eyes, B-scan in 129 (63.9%) patients were normal, 19 (9.4%) of patients had synchitic vitreous, 23(11.4%) of patients had incomplete Posterior Vitreous Detachment (PVD), 5 (2.5%) had complete PVD, 1(0.5%) had patient had asteroid hyalosis, 7(3.5%) had vitreous hemorrhage (VH), 6(3%) had retinal detachment, 1 (0.5%) had asteroid hyalosis with VH, 4 (2%) had RD with VH, 5(2.5%) VH with PVD, 1 (0.5%) had Posterior staphyloma with PVD, 1(0.5%) had Complete PVD with Asteroid hyalosis. Majority of the patients had no pathology, followed by vitreous pathologies like synchisis, PVD, VH and RD.
Faheem et al9 studied 227 eyes of 200 patients with cataract. On B-Scan they found posterior segment pathology in 18 (7.90%) eyes. Normal posterior segment was seen in 209 (92.10%) eyes. The most common pathology was posterior staphyloma in 8(3.52%) eyes, Vitreous haemorrhage in 3 eyes, Intravitreal membrane in 2 eyes, Chorioretinal thickening in 2 eyes, Retinal detachment in 2 eyes, Optic disc edema in 1 eye. Out of 200 patients 163 (81.5%) had no any systemic or ocular risk factor for abnormal posterior segment, where as 37 (18.5%) were associated with systemic and ocular risk factors like diabetes, hypertension and early age, posterior synechiae, raised intraocular pressure and keratic precipitates.3
Chanchlani et al10 conducted a study on 425 eyes of 400 patients to analyse the role of B-scans ultrasound in detecting posterior segment pathology in hyper mature cataract cases. They found no pathology in 388 (91.30%) cases, Posterior staphyloma in 15 (3.52%) cases, Vitreous hemorrhage in 7 (1.64%), Vitreous membrane in 5(1.20%), Chorioretinal Thickening in 6 (1.41%), and Retinal detachment 4 (0.94%) cases.
Antcliff RJ et al11 conducted a retrospective study in a consecutive group of diabetic patients in 74 operated eyes who underwent phacoemulsification and intraocular lens implantation over a 2 year period. They concluded that the outcome of cataract surgery in diabetics is largely determined by the degree of maculopathy. Phacoemulsification and extracapsular cataract surgery give similar visual results. Diabetic retinopathy should not be considered a contraindication to small-incision cataract surgery and phacoemulsification. In our study, postoperative fundoscopy revealed normal fundus in 114(56.4%) patients, mild NPDR in 14 (6.9%) patients, moderate NPDR in 23(11.4%) patients, severe NPDR in 6(3%) patients, PDR in 5(2.5%) patients, advanced diabetic eye disease (ADED) in 12 patients (5.9%), mild NPDR with PVD seen in 6 (3%) patients, moderate NPDR with clinically significant macular edema (CSME) in 4 (2%) patients, severe NPDR with CSME in 2(1%) patients, VH in 5 (2.5%) patients, tractional retinal detachment (TRD) in 2(1%) patients, cystoids macular edema (CME) in 7(3.5%) patients, posterior staphyloma with PVD with mild NPDR in 1(0.5%) patient, PVD in 1(0.5%) patient. Patients with mild and moderate NPDR were advised antioxidants and were advised for good glycemic control and regular follow-ups. Patients with CME and CSME were treated with topical NSAIDs like Nepafenac eye drops thrice a day. Patients with PDR underwent panretinal photocoagulation at 4 weeks after cataract surgery. Patients with VH/TRD/ADED were referred to higher centers for vitreoretinal surgery. All the patients were adviced for good glycemic control and regular follow-ups.
Henricsson et al 13 analysed DR before and after cataract surgery in 70 patients and concluded that the patients with PDR, obtained good visual acuity, better than in most previous studies. Poor glycemic control was found to be an important factor for the progression of diabetic retinopathy after cataract surgery.
Our study showed, among the 129 patients with normal B-scan, 97 (75.2%) had normal fundus with no DR changes and 25% of the patients had significant DR changes which included 5(3.9%) patients with mild NPDR, 19(14.7%) patients with moderate NPDR, 4(3.1%) patients with severe NPDR, 4(3.1%) patients with CME (P < 0.001). This was statistically significant. These 25% of the patients are the reason for explaining the guarded visual prognosis.
Among the 19 patients with synchitic vitreous in B-scan, 9(47.4%) patients had normal fundus, 2 (10.5%) had mild NPDR, 3(15.8%) had moderate NPDR, 2(10.5%) had sever NPDR, 1(5.3%) had PDR, and 2(10.5%) had CME. Among 23 patients with incomplete PVD, 7 (30.4%) patients had normal fundus, 7(30.4%) had mild NPDR, 2 (8.7%) had mild NPDR with PVD, 4 (17.4%) had moderate NPDR with CSME, 2(8.7%) had severe NPDR with CSME, 1(4.3%) had CME. Among 5 patients with complete PVD, 1 (20%) had severe NPDR, 4(80%) had mild NPDR with PVD. One patient with asteroid hyalosis on B-scan had PVD (p = 0.000). This was found to be statistically significant. Among the 48 patients with age related vitreous changes including synchitic vitreous, asteroid hyalosis and PVD, 17 (35.4%) patients had normal fundus and significant percentage (64.5%) of patients had DR changes including NPDR, PDR and CME. Patients with these age related vitreous changes had higher chances of DR changes compared to the patients with normal B-scan. Hence, the need for explaining the guarded visual prognosis in these patients is a must.
Among 6 patients with RD on B-scan, 3(50%) had ADED, 3(50%) had PDR. One patient with asteroid hyalosis + VH on B-scan had moderate NPDR with PVD. Among
7 patients with VH in B-scan, 1(14.3%) had PDR, 1(14.3%) had ADED (VH + TRD), 5(71.4%) had VH. Four patients with RD + VH on B-scan had ADED, one patient with Posterior Staphyloma + PVD had Posterior Staphyloma + PVD mild NPDR. (p = 0.150). These 5.5% of the patients with preoperative Proliferative diabetic Retinopathy changes like
Vitreous hemorrhage and Retinal detachment will have to be definitely explained about the guarded or nil visual prognosis.
B-scan is helpful in identifying the structural abnormality of vitreoretinal complex. However, all normal B-scan picture does not mean the patient will have 6/6 vision postoperatively because significant percentage of patients can have DR changes and macular edema which is the major cause for low vision postoperatively. These macular edema/DR changes cannot be detected preoperatively with B-scan. Hence, any diabetic patient with dense cataract cannot be guaranteed with good vision. Thus, guarded visual prognosis has to be explained to all the diabetic patients with mature and hypermature cataract preoperatively.