Preliminary evaluation of the safety of the lens and the ora serrata during vitrectomy with scleral incisions at 5.0 mm behind the limbus / 中华眼底病杂志

ABSTRACT

Objective To evaluate the safety to perform 23G vitrectomy with scleral incisions at 5.0 mm behind the limbus.Methods This is a prospective uncontrolled case study.The data of 140 consecutive primary 23G vitrectomy patients (145 eyes) were enrolled in this study.There were 56 males (59 eyes) and 84 females (86 eyes),with the mean age of (56.34 ± 9.98) years and axial length of (23.99± 2.57) mm.There were 139 phakic eye and 6 aphakic eyes.All the eyes received 23G pars plana vitrectomy with scleral incisions at 5.0 mm behind the limbus.To measure the normal Chinese adult parameters of anteroposterior axis of the eyeball,lens thickness and scleral distances from the limbus to the plane passing through the lens posterior apex,the head CT scans of 105 patients without eye diseases in our hospital were studied during the same period of time for these vitrectomy surgeries.Pearson correlation analysis was used to analyze the relationship between age,anteroposterior axis of eyeball,lens thickness and scleral distances from the limbus to the plane passing through the lens posterior apex.Results Surgical related complications included retinal tears close to the scleral incision sites (3/145 eyes,2.1％) and lens injury (3/121 eyes,2.5％).No other surgical complications occurred,such as retinal hemorrhage,supra-choroidal expulsive hemorrhage and iatrogenic retinal detachment.Based on CT images,the average scleral distance from limbus to the plane passing through the lens posterior apex,anteroposterior axis of eyeball and lens thickness was (6.72± 0.81),(24.39± 0.97),(4.22 ± 0.47) mm,respectively.The results of Pearson correlation analysis showed that age and lens thickness had statistically significant correlation (r=0.328 9,P=0.000 6).Conclusion Primary 23G pars plana vitrectomy with incisions at 5.0 mm posterior to the limbus is safe.