Re: “Evisceration With Implant Placement Posterior to the Posterior Sclera”
The authors have included patients undergoing evisceration with normal or near-normal-sized eyeball in their study. However, phthisical eyeballs are often disorganized and are shrunken in size with small axial length. Hence making adequate sized scleral flaps might be difficult in these eyes which might limit the size of the implant which can be inserted and also affect the implant exposure rate.
We have used a technique of modified evisceration with retroscleral implant placement in severely phthisical eyes with reduced axial length and analyzed our results retrospectively to assess the size of the implant placed and the implant exposure rate. Our technique of evisceration with retroscleral placement of implant is as described by authors with the following modification. After evisceration of the intraocular contents, 2 radial anterior sclerotomies are made in superonasal and inferotemporal quadrants to make 2 anterior sclera flaps. Instead of 2, we make 4 posterior radial sclerotomies and join them circumferentially around the optic head to form 4 posterior scleral flaps. The optic nerve head is disinserted and pushed back and a spherical polymethylmethacrylate implant is inserted through the anterior scleral opening and pushed behind the sclera shell into the intraconal space. In severely phthisical eyes where the rim of intact sclera between the anterior and posterior flaps is not of adequate diameter to allow the implant to be inserted into the intraconal space, we put 2 preplaced sutures with 6-0 vicryl and join the anterior and posterior radial scleral flaps in the superonasal quadrant to form a continuous radial sclerotomy from anterior to posterior. This allows for expansion of the scleral shell that helps in placement of an adequate sized implant. The preplaced sutures are tied to reform the sclera rim and the anterior and the posterior sclera flaps are closed in layers to form 3 layers of sclera flaps over the implant. We believe that maintaining an intact circumferential rim of sclera between the anterior and the posterior flaps allows the implant to remain retroplaced and prevent its forward migration. The rest of the technique of surgery is as described by the authors.
Our study included 13 patients with severely phthisical eyes who underwent evisceration with retroscleral placement of polymethylmethacrylate implant using the technique described above. The axial length of the eyes ranged from 7.4 to 14.5 mm with an average of 8.7 mm. The average size of the implant used was 19 mm. All patients were fitted with a customized ocular prosthesis 6 to 8 weeks postoperatively and pegging was not performed in any patient. The mean follow-up duration was 27 weeks. None of the patient had implant exposure or migration or any forniceal shortening.
Our data complement the results as described by Jordan et al.1 In addition, the modified technique of evisceration used by us also allows placement of an adequate sized implant in the retroscleral space following evisceration in severely phthisical eyes with reduced axial length.