Techniques of orthotopic renal transplantation. II. Size-matched porcine grafts in monkey recipients

ABSTRACT Purpose As a classical xenotransplantation model, porcine kidneys have been transplanted into the lower abdomen of non-human primates. However, we have improved upon this model by using size-matched grafting in the orthotopic position. The beneficial aspects and surgical details of our method are reported herein. Methods Donors were two newborn pigs (weighting 5 to 6 kg) and recipients were two cynomolgus monkeys (weighting, approximately, 7 kg). After bilateral nephrectomy, kidneys were cold-transported in Euro-Collins solution. The porcine kidney was transplanted to the site of a left nephrectomy and fixed to the peritoneum. Results Kidneys transplanted to the lower abdomen by the conventional method were more susceptible to torsion of the renal vein (two cases). In contrast, early-stage blood flow insufficiency did not occur in orthotopic transplants of theleft kidney. Conclusions Size-matched porcine-primate renal grafting using our method of transplanting tothe natural position of the kidneys contributes to stable post-transplant blood flow to the kidney.

Increased choroidal thickness in patient with high-altitude retinopathy.

We report a case of high‑altitude retinopathy with increased choroidal thickness detected by spectral‑domain optical coherence tomography  (SD‑OCT). A  36‑year‑old Japanese man developed an acute vision decrease in his left eye after he had trekked at an altitude of 4600  m in Tibet for 1  week. His visual acuity was 20/20 OD and 20/200 OS with refractive errors of  − 0.25 diopters  (D) OD and  − 0.50 D OS 3  weeks after the onset of the visual decrease. Funduscopic examinations revealed multiple intraretinal hemorrhages bilaterally and a macular hemorrhage in the left eye. SD‑OCT showed that the thickness of choroidal layer at the fovea was 530  μm OD and 490  μm OS which is thicker than that in normal subjects of approximately 300  μm. We suggest that the increase in the retinal blood flow under hypoxic conditions may be associated with an increase in the choroidal blood flow resulting in an increase in choroidal thickness.