Visual loss after renal transplantation

Demonstration of technical feasibility and viability of whole eye transplantation in a rodent model

INTRODUCTION

Whole eye transplantation (WET) holds promise for vision restoration in devastating/disabling visual loss (congenital or traumatic) not amenable to surgical or neuroprosthetic treatment options. The eye includes multiple tissues with distinct embryonic lineage and differential antigenicity. Anatomically and immunologically, the eye is unique due to its avascular (cornea) and highly vascular (retina) components. Our goal was to establish technical feasibility, demonstrate graft viability, and evaluate histologic changes in ocular tissues/adnexae in a novel experimental model of WET that included globe, adnexal, optic nerve (ON), and periorbital soft tissues.

METHODS

Outbred Sprague-Dawley rats (n = 5) received heterotopic vascularized WET from donors. Each WET included the entire globe, adnexa, ON, and periorbital soft tissues supplied by the common carotid artery and external jugular vein. Viability and perfusion were confirmed by clinical examination, angiography and magnetic resonance imaging (MRI). Globe, adnexal, and periorbital tissues were analyzed for histopathologic changes, and the ON was examined for neuro-regeneration at study endpoint (30 days) or Banff Grade 3 rejection in the periorbital skin (whichever was earlier).

RESULTS

Gross examination confirmed transplant viability and corneal transparency. Average operative duration was 64.0 ± 5.8 min. Average ischemia time was 26.0 ± 4.2 min. MRI revealed loss of globe volume by 36.0 ± 2.8% after transplantation. Histopathology of globe and adnexal tissues showed unique and differential patterns of inflammatory cell infiltration. The ON revealed a neurodegeneration pattern.

CONCLUSION

The present study is the first in the literature to establish an experimental model of WET. This model holds significant potential in investigating mechanistic pathways, monitoring strategies or developing management approaches involving ocular viability, immune rejection, and ON regeneration after WET.

Analysis of the relationship between postoperative ophthalmic complications and dialysis time of pre-kidney transplantation

AIM

To determine the influence of the dialysis time before kidney transplantation on postoperative ophthalmic complications.

METHODS

One hundred and eighty three patients who were given the follow-up after kidney transplantation were selected, including 124 males and 59 females. The dialysis time before kidney transplantation was (2.9±2.1) years. Among them, there were 93 cases having cadaveric renal transplantation and 90 cases having living relative renal transplantation. The conditions of ophthalmic complications in all the patients after kidney transplantation were investigated and the incidence rate on ophthalmic complications having different dialysis time before kidney transplantation was given Chi-square test and Chi-square linear trend test.

RESULTS

Among 183 patients with kidney transplantation, 95 patients (51.9%) had at least one ophthalmic complication and the rest 88 patients (48.1%) had no significant abnormality at the eye region. The most common ophthalmic complications were pinguecula/conjunctival degeneration (31 cases), the following was caligo lentis (24 cases). The main manifestations were grayish white granule and plaque turbidity occurred in posterior capsule at the posterior pole of crystaline lens. The angulus iridocornealis of 5 patients (5.3%) with cataract and glaucoma were all open-angle through the detection by gonioscope. Through visual field examination, there were 2 patients with paracentral scotoma, 2 patients with arcuate scotoma and one case with nasal step.

CONCLUSION

The experiments verify that the incidence of glaucomawas relates to the dialysis time before kidney transplantation, and the incidence rate might be higher if the dialysis time is longer.

Cholelithiasis and thrombosis of the central retinal vein in a renal transplant recipient treated with cyclosporin

The use of cyclosporin has been associated with the development of cholelithiasis in transplant recipients. Cholelithiasis in turn enhances the effects of cyclosporin on increased platelet aggregation. In this report, a patient who had undergone a renal transplantation as a result of malignant hypertension, and who was on immunosuppressive therapy consisting of cyclosporin, prednisone and azathioprine, developed thrombosis of the central retinal vein 5 years following the transplantation. Seven years after the transplantation, cholelithiasis, cholecystitis, cholangitis and subsequently secondary chronic biliary sclerosis were detected. Latero-lateral anastomosis between the common bile duct and duodenum was performed during explorative laparotomy and ursodeoxycholic acid treatment was introduced. The possible inter-relationship of the cholestatis, central retinal vein thrombosis and immunosuppression are discussed.

Major ocular complications after organ transplantation

We reviewed the existing literature on major ocular complications after organ transplantation. Disorders of the ocular surface were not considered. Published reports were selected through a computerized MEDLINE search of the literature. The incidence of cataract or increased intraocular pressure due to immunosuppressant therapy are common; although retinopathy, optic neuropathy, or central nervous system involvement are less frequent they may be related to severe and irreversible visual loss. Patients undergoing organ transplantation should receive careful and regular ocular examinations.