Case Reports

Corneal decompensation and poor visual quality after implantable miniature telescope (IMT) surgery: restoration of visual potential with Descemet's stripping automated endothelial keratoplasty (DSAEK) surgery

Case Report Details

First Author: M.Rizk LEBANON

Co Author(s):    N. Jabbour   B. Abiad   G. Mollayyes              

Abstract Details

Purpose:

Emphasize the adverse effects of the Implantable Miniature Telescope (IMT) on visual acuity (VA), corneal health, quality of life, and psychosocial vision-targeted dependency in an 80-year-old patient with advanced dry age-related macular degeneration (AMD) both eyes (OU). Discuss how some VA was regained after Descemet Stripping Automated Endothelial Keratoplasty (DSAEK) Surgery alone leading to better social functioning of the patient.

Setting:

An 80-year-old man with advanced dry AMD and 20/400 vision OU underwent IMT surgery. After that, he developed persistent corneal edema, endothelial cell loss, visual acuity loss, and psychosocial disability. The IMT was not removed and a DSAEK surgery was performed. This led to improvement of the patient’s symptoms.

Report of Case:

AMD is the leading cause of legal blindness in the world. In the final stage of AMD, a central scotoma leads to very poor visual acuity (VA). This does not usually affect the peripheral vision. The Implantable Miniature Telescope (IMT) is a Galilean telescopic prosthesis that constitutes an intraocular magnifying system. It is indicated in patients with stable, nonfoveal sparing, bilateral, end-stage AMD with scotomas. It is implanted in one of the patient's eyes providing improved visual acuity while the nonimplanted eye provides peripheral vision for ambulation. Although studies show improvement in far and near visual acuity and quality of life after this surgery, very few reports in the literature describe the cases where IMT leads to serious adverse effects. Known postoperative problems are visual field restrictions and the demanding postoperative visual rehabilitation. In this report we discuss less reported adverse effects in the literature. An 80-year-old man with advanced AMD OU underwent IMT implantation in his right eye (OD) two years prior to presentation after which he developed persistent corneal edema, corneal decompensation, and endothelial cell loss with consequent poor VA and psychological burden. On the day of presentation to our clinic his vision had dropped from 20/400 pre operatively to light perception. Intraocular pressure was within normal ranges OU. Slit lamp exam OD revealed corneal edema and haze preventing from assessing further ocular structures. Central corneal thickness OD was 783 nm. The IMT however was difficultly seen supero-nasally displaced. Ultrasound Biomicroscopy (UBM) showed acceptable corneal endothelium-IMT distance. The decision of keeping the IMT in place and performing only a DSAEK was therefore made. DSAEK surgery was performed successfully with visual acuity improving to counting fingers one week after surgery, partial clearing of the cornea and improved patient psychosocial state. The patient continued to improve over the next weeks.

Conclusion/Take Home Message:

IMT surgery, although is depicted in many studies as a surgery whose benefits exceed its adverse ocular effects, does not always pass by without complications. In cases of severe persistent corneal edema and acceptable corneal endothelium-IMT distance a DSAEK surgery alone while leaving the IMT implant in place can be attempted as shown in this case. This can improve the corneal edema and retrieve some visual potential leading to improvement of the psychosocial state of the patient. Therefore, pre-operative meticulous selection of patients eligible to IMT surgery should be done to avoid the possible burdensome complications post-operatively.

Financial Disclosure:

None