Adverse effects of systemic immunosuppression in keratolimbal allograft.

Purpose. Keratolimbal allograft (KLAL) is a treatment for limbal stem cell deficiency. One disadvantage is systemic immunosuppression to avoid rejection. Our purpose was to examine the adverse effects of systemic immunosuppression in KLAL. Methods. A retrospective case review of 16 patients with KLAL who received systemic immunosuppression consisting of a corticosteroid, an antimetabolite, and/or a calcineurin inhibitor was performed. Patients were monitored for signs, symptoms, or laboratory evidence of toxicity. Results. Eleven of 16 patients (68%) experienced an adverse effect. The average age of those with adverse effects was 43.5 years and without was 31.4 years. Ten of 11 patients (91%) had resolution during mean followup of 16.4 months. No serious adverse effects occurred. The most common included anemia, hyperglycemia, elevated creatinine, and elevated liver function tests. Prednisone and tacrolimus were responsible for the most adverse effects. Patients with comorbidities were more likely to experience an adverse effect (82% versus 20%, P = 0.036). Conclusions. KLAL requires prolonged systemic immunosuppression. Our data demonstrated that systemic immunosuppression did not result in serious adverse effects in our population and is relatively safe with monitoring for toxicity. In addition, we demonstrated that adverse effects are more likely in older patients with comorbidities.

Limbal fibroblast conditioned media: a non-invasive treatment for limbal stem cell deficiency.

PURPOSE: Limbal fibroblasts are known to regulate the maintenance and differentiation of the corneal epithelium including the limbal epithelial stem cells. This study examined the effect of limbal fibroblast conditioned media in a mouse model of limbal stem cell deficiency. METHODS: Limbal stem cell deficiency was created in C57/Bl6 mice by performing a limbus to limbus epithelial debridement. The mice were treated topically for 3 weeks with conditioned media derived from human limbal fibroblasts. The control mice were treated with skin fibroblast conditioned media or Dulbecco's serum-free medium. RESULTS: The mice treated with limbal fibroblast conditioned media demonstrated substantial growth of corneal type epithelial cells on the corneal surface with less conjunctival goblet cells. By contrast, the control treated corneas were found to be covered primarily by conjunctival type epithelium. CONCLUSIONS: Cell culture media conditioned by limbal fibroblasts appear to contain factor(s) that are therapeutically beneficial in a model of limbal stem cell deficiency. The current results further support the notion that the essential limbal stem cell niche is provided by limbal fibroblasts and suggest a new, non-invasive option in the treatment of limbal stem cell deficiency.

Down-regulation of Notch signaling during corneal epithelial proliferation.

PURPOSE: We evaluated the expression and activation of Notch pathway genes in the adult human and murine corneal epithelium during proliferation. METHODS: The expression of Notch pathway genes in the limbal and central human corneal epithelium was compared by reverse transcription polymerase chain reaction (RT-PCR). Their expression pattern was examined by immunofluorescence and in situ hybridization. The temporal expression of Notch1 during murine wound healing was assessed by RT-PCR. Notch activity was determined using western blot for the Notch intracellular domain (NotchIC). The expression of Hes1 was evaluated in cell culture. RESULTS: The expression of Notch1 and Jagged1 was higher in the human limbal epithelium while the expression of Hes1 and Hes5 was higher in the central cornea. Expression of Notch1, Jagged1, and Hes1 was found predominantly in the basal and immediate suprabasal cells. During neonatal corneal development, NotchIC was detected in occasional cells at P10 while at P15 and P90, it was found in the basal and early suprabasal layers. NotchIC was found to be lower in the limbal compared to central corneal epithelium. The expression of Notch1 was lower at 24 h post-wounding but was completely restored in six days. The levels of NotchIC were decreased at 24 h post-wounding and after application of topical phorbol myristate. In vitro, the expression of Hes1 was higher in confluent cells maintained under high calcium conditions. CONCLUSIONS: The inverse correlation between Notch signaling and the proliferative status of the corneal epithelium is consistent with the idea that Notch plays a role in corneal epithelial differentiation.

Intraocular hemorrhage after systemic thrombolytic therapy in a patient with exudative macular degeneration.

PURPOSE: To report a hemorrhagic complication from thrombolytic therapy in a patient with exudative macular degeneration. CASE REPORT: A 75 year old patient with exudative macular degeneration developed pain and loss of vision in the left eye shortly after receiving tissue plasminogen activator (t-PA) for a myocardial infarction. Examination revealed the patient to be in angle closure. A CT scan revealed the etiology of the angle closure to be a dense vitreous hemorrhage pushing the iris-lens diaphragm forward. Intraocular pressure was treated successfully, but the final visual acuity was only light perception. CONCLUSIONS: Thrombolytic therapy can lead to devastating intraocular hemorrhages. The presence of exudative macular degeneration may potentially increase the risk of developing such complications.

Keratitis caused by Candida glabrata in a patient with chronic granulomatous disease.

PURPOSE: To report an unusual ocular presentation of Candida glabrata in a patient with chronic granulomatous disease. METHODS: Interventional case report. A 15-year-old boy with chronic granulomatous disease presented with bilateral limbal infiltrates. He had been receiving broad-spectrum systemic antibiotics for recurrent liver abscesses. The keratitis did not respond to antibiotics and did not resolve after a course of topical steroids. RESULTS: Corneal cultures revealed Candida glabrata. The same species was simultaneously isolated from the surgical drainage of the liver abscesses. The ocular and hepatic findings resolved on intravenous amphotericin B. CONCLUSION: Candida glabrata has recently emerged as an important nosocomial pathogen. It may present as a limbal keratitis in the setting of systemic infection.

Conjunctival epithelial cells cultured on human amniotic membrane fail to transdifferentiate into corneal epithelial-type cells.

PURPOSE: Previous studies on the use of human amniotic membrane (HAM) in rabbit stem cell deficiency models have found the new epithelium growing over the HAM to express cornea-specific keratins (K3 and K12) in 40% of the cases, suggesting that HAM may have induced conjunctival epithelial cells to transdifferentiate into cornea-type epithelial cells. The current study was performed to determine whether HAM could induce transdifferentiation of conjunctival epithelia] cells when cultured in vitro. METHODS: Conjunctival grafts taken from the fornices of New Zealand white rabbits (6-12 weeks old) were placed over HAMs and lifted to an air-media interface using polypropylene double rings. These cultures were maintained in supplemented hormonal epithelial medium with and without 3T3 feeder cells. Rabbit corneal epithelial cells were cultured similarly using strips of keratolimbal grafts placed over HAM. The cultures were terminated at various times between the 8th and 15th day. The cultured epithelial cells were examined histologically and immunohistochemically using monoclonal antibodies AK-2 (to K12 keratin), AM-3 (to goblet cell mucin), and AE-5 (to K3 keratin). RESULTS: Both conjunctival and corneal epithelial cells cultured on HAMs showed multilayered, differentiated epithelial structures. On immunohistochemical examination, both epithelial cells stained positive for AE-5. None of the cultured conjunctival epithelial cells stained positively for AK-2, while the corneal epithelial cells showed positive staining with AK-2. There were no AM-3-positive goblet cells in either epithelial cell culture. There was no difference in the immunohistochemical patterns between cultures with or without 3T3 feeder cells. However, culture without feeder cells seemed to manifest a more degenerative appearance than those with feeders. CONCLUSION: HAM does not induce transdifferentiation of conjunctival epithelial cells into corneal-type epithelial cells under the in vitro culture conditions used in this study.

Long-term results of transsclerally sutured posterior chamber lenses in penetrating keratoplasty.

PURPOSE: To evaluate the long-term safety and efficacy of transsclerally sutured posterior chamber lenses in penetrating keratoplasty. METHODS: This was a retrospective review of 130 patients who underwent penetrating keratoplasty and placement of a transsclerally sutured posterior chamber lens with at least 1 year of follow-up. The mean follow-up period was 38.8 months. There were 61 patients who had been followed for at least 3 years (mean, 59 months). RESULTS: At follow-up the visual acuity was 20/40 or better in 40 patients (31%) and 20/50 to 20/200 in 48 patients (36%). The primary reasons for decreased visual acuity were age-related macular degeneration (18%) and graft failure (13%). New-onset glaucoma was found in 19 of 82 patients (23%). In the 48 patients who had elevated intraocular pressures preoperatively, the pressure improved in 13 patients (27%) and worsened in 12 patients (25%). Exposure of the haptic suture through the conjunctiva occurred in 14 patients (11%) at an average of 12 months after surgery. Of these, seven (19%) occurred in patients with conjunctival flaps, and seven (16%) in patients who had scleral flaps covering the haptic suture. No erosions occurred in the cases in which the suture was rotated inside the eye. CONCLUSION: Improvements in the surgical technique have made transsclerally sutured posterior chamber lenses safer in patients with inadequate capsular support. The long-term visual results in penetrating keratoplasty are acceptable and comparable to those of other techniques.

Tandem scanning confocal microscopic analysis of differences between epithelial healing in limbal stem cell deficiency and normal corneal reepithelialization in rabbits.

PURPOSE: To analyze the differences in epithelial healing between limbal stem cell-deficient corneas and normal corneas by using in vivo confocal microscopy. METHODS: Two different injury models were made in rabbit eyes by using n-heptanol to create a corneal epithelial defect with (limbal stem cell-deficiency model) or without (normal corneal reepithelialization model) peripheral limbal keratectomy. Using a tandem scanning confocal microscope (TSCM), we examined and compared the epithelial healing processes of the two different injury models. Impression cytology and pathologic examination were done on limbal stem cell-deficient corneas. RESULTS: In limbal stem cell-deficient corneas, the healing epithelial cells were smaller and more variable in size compared with those in normal corneas. In limbal stem cell-deficient corneas, the epithelial thickness varied from one to six cell layers, with the middle and basal cell layer cells being lined up in a certain direction in some areas. The basement membrane was uneven and partially deficient; in some areas, the deep basal epithelial cells were mixed with fibrous strands extending from the anterior stroma. New vessels were located in various levels, from epithelium to deep stroma. These findings were not seen in the normal corneal reepithelialization. In both epithelial-healing models, particularly in the normal corneal reepithelialization, the superficial squamous cells in the early healing stage were considerably larger than those in nontraumatized normal corneas. CONCLUSION: TSCM is a useful technique for studying the in vivo microscopic structure of many corneal diseases and injury models sequentially over time.

Comparison between the refractive results of combined penetrating keratoplasty/transsclerally sutured posterior chamber lens implantation and the triple procedure.

PURPOSE: We determined how accurately we could predict the intraocular lens (IOL) power for a combined penetrating keratoplasty and transsclerally sutured posterior chamber lens implantation procedure (PK/TS-SPCL) compared with the Triple procedure (penetrating keratoplasty, extra-capsular cataract extraction, and IOL insertion). METHODS: We retrospectively evaluated the postoperative refractive results of 27 patients who had undergone PK/TS-SPCL and compared them with those of 46 patients who had undergone a Triple procedure. All patients with a final visual acuity > 20/50 who had surgery at the University of Minnesota between January 1988 and December 1993 were included in this study. RESULTS: The mean postoperative deviation from the predicted refractive error was 1.79 D for the Triple group and 1.81 D for the PK/TS-SPCL group (p = 0.95). Sixty-three percent of the Triple patients and 67% of the PK/TS-SPCL patients were within -2.00 D and +2.00 D of their predicted refractive error. As a group, the Triple patients had a mean postoperative keratometry reading of 44.64 compared with 45.58 for the PK/TS-SPCL patients (p = 0.12). CONCLUSION: These results indicate that our accuracy in predicting the IOL implant power in PK/ TS-SPCL is quite comparable with that obtained for the Triple procedure, and our refractive results for each group are quite similar.

Gonioscopic evaluation of haptic position in transsclerally sutured posterior chamber lenses.

PURPOSE: To determine the haptic position in transsclerally sutured posterior chamber lenses. METHODS: Fifty eyes with transsclerally sutured posterior chamber lenses were evaluated gonioscopically to determine the superior haptic position using previous peripheral iridectomies. RESULTS: The superior haptic of the transsclerally sutured posterior chamber lens was visualized in 31 (62%) of the eyes. In 24 (77%) of the 31 eyes, the haptic was within the ciliary sulcus, and in seven (23%), it was located posterior to the sulcus. A fibrotic membrane was detected around the sutured haptic in 20 (83%) of the 24 lenses located within the sulcus, whereas no fibrosis was seen surrounding the seven haptics outside the sulcus (P < .0001). CONCLUSIONS: Proper positioning of the haptics may be correlated with the development of fibrosis surrounding the haptic and therefore may be an important factor in the long-term stability of transsclerally sutured posterior chamber lenses.

Heart transplantation for patients over age 60.

As the proportion of people over age 60 in our society continues to rise, so does the number of potential heart transplant candidates. Advanced recipient age, however, has long been used as an exclusion criterion for transplantation, though the upper age limit remains poorly defined. The purpose of our study was to analyze the outcomes of 31 heart transplant recipients over age 60 at our institution. They were followed with regard to early and late morbidity and mortality. Mean follow-up time was 50 months. The 1- and 5-yr survival rates were 90% and 85%. These rates were not significantly different compared with younger (age 18 to 59) recipients transplanted in the same time period. The older recipients more frequently developed osteoporotic changes as well as cutaneous and visceral malignancies, but had infrequent rejection episodes. Overall, heart transplantation is safe and effective for patients over age 60 with end-stage congestive heart failure. Both 1- and 5-yr survival rates are well within the acceptable range and do not differ significantly from younger recipients. Individualized immunosuppression might help reduce the incidence of malignancy in older recipients, but further studies are needed. Matching donor and recipient age would make the best use of available organs.

Adjunctive coronary endarterectomy: improved safety in modern cardiac surgery.

BACKGROUND: Advances in cardiac surgery have led to an improved safety record for coronary endarterectomy. METHODS: We retrospectively reviewed the cases of 64 patients who underwent adjunctive coronary endarterectomy between August 1988 and February 1992. There were 44 men, and the mean age was 65 years. Forty-one patients (64%) had sustained a previous infarction. Overall, endarterectomy was performed on 76 vessels, and the right coronary system was involved in 46 (61%). RESULTS: The postoperative infarction rate was 5%. Incomplete occlusion ( < 90% stenosis) of the endarterectomized vessel significantly increased the risk of infarction (p < 0.05). There were two early deaths (3%). The mean follow-up was 46 months. Clinically, 91% of the survivors were angina free, and 80% had no symptoms of heart failure at the time of follow-up. Left ventricular function had improved in 36% of those restudied (5/14). A total of 17 recatheterizations were done at a mean interval of 19 months after operation. The endarterectomy graft patency rate was 80% (16/20) compared with 78% (28/36) for conventional grafts ( p = not significant). The actuarial survival rates were 89% and 71% at 1 year and 5 years, respectively. A history of previous infarction was significantly associated with higher long-term mortality (p < 0.02). CONCLUSIONS: Overall, these results demonstrate that in modern cardiac surgery, coronary endarterectomy is safer than previously thought and can be used effectively to achieve complete revascularization in selected patients.