Surgical management of diabetic tractional retinal detachments.

Tractional retinal detachment is an end-stage form of diabetic retinopathy that occurs when contractile forces in the vitreous and neovascular tissue lead to the detachment of the neurosensory retina. We review the literature related to the management of this disease. Preoperative planning includes appropriate patient selection, diagnostic and prognostic imaging, and medical optimization with reduction of systemic risk factors. Use of antivascular endothelial growth factor for preoperative treatment has had significant benefits for tractional retinal detachment repair in improving surgical efficiency and outcomes. Advances in microsurgical instrumentation are discussed, with attention to small-gauge vitrectomy with improved flow dynamics, viewing strategies, and lighting allowing bimanual surgery. Special emphasis is placed on bimanual surgical technique, choice of tamponade, and the avoidance of iatrogenic damage. Complications and special considerations are further explored. Based on our compilation of relevant literature, we propose a surgical algorithm for the management of these complex patients.

OCULAR MANIFESTATIONS OF PRIMARY MYELOFIBROSIS.

PURPOSE: To report ocular manifestations of idiopathic primary myelofibrosis in a patient with relapsed primary myelofibrosis. METHODS: Observational case report. RESULTS: A 57-year-old African American male with history of primary myelofibrosis, diagnosed by bone marrow aspirate and biopsy, believed to be in remission was referred to us for bilateral angle-closure glaucoma refractory to medical treatment and laser peripheral iridotomy. His fundus examination revealed serous retinal detachments, choroidal effusions, and Roth spots, and B-scan revealed his angle closure was due to annular anterior ciliochoroidal effusions. The patient was taken to surgery for a pars plana vitrectomy with radial sclerotomies performed to relieve the patient's eye pressure in the left eye. Cytologic analysis of the choroidal effusions revealed neutrophilic infiltrates with immature forms and erythroid precursors, suggesting a neoplastic infiltration from the patient's primary myelofibrosis. The patient's vision and ocular symptoms significantly improved after chemotherapy. Repeat bone marrow aspiration and biopsy confirmed the patient's primary myelofibrosis with no progression to acute leukemia despite his high leukocyte count. CONCLUSION: Neoplastic infiltration of primary idiopathic myelofibrosis into the eye and surrounding structures, which is scantly described in the current literature, may be an early sign of new onset or relapsing primary myelofibrosis. Chemotherapy can be very effective in the ultimate treatment and remission of these ocular symptoms.

Intracranial Extension of an Orbital Epidermoid Cyst.

Epidermoid and dermoid cysts represent the most common cystic lesions of the orbit and commonly arise from bony sutures or the intradiplpoic space of orbital bones. Massive intracranial extension of an epidermoid cyst arising from the intradiploic space of an orbital bone is very rarely seen. We present a case of a 55-year-old male who was incidentally found to have massive intracranial extension of an intradiploic epidermoid cyst of the superolateral orbital bone with minimal symptoms. The cyst was completely excised via a pterional craniotomy and lateral orbitotomy by neurosurgery and oculoplastic surgery teams. The patient suffered no complications and is doing very well.

Diabetic and non-diabetic human cornea and tear γ-glutamyl transpeptidase activity.

BACKGROUND: Diabetes-related eye disease is due in part to oxidative stress. Gamma-glutamyl transpeptidase (GGT) is a γ-glutamyl cycle enzyme that protects against oxidative stress via glutathione recapture. This study investigates corneal and Schirmer tears GGT activity in diabetic and non-diabetic adults aged 50 to 83 years old. METHODS: GGT activity was determined by colorimetric assay on 50 corneas from 14 diabetic (without keratopathy) and 20 non-diabetic donors and on Schirmer type 1 test strips (no anesthesia) of 14 diabetic and 14 non-diabetic subjects. RESULTS: Type 1 (T1) diabetic cornea GGT activity was 40% lower than Type 2 (T2) diabetic cornea GGT activity (P = 0.04), but GGT activity was similar for corneas (without keratopathy) from diabetic and non-diabetic donors (P ≥ 0.44 for all). The number of endothelial cells/unit of GGT activity in diabetic corneas was 22% higher (P = 0.1) than in non-diabetic corneas. GGT activity per Schirmer strip and GGT activity per mm of tears were 36% and 50% higher (P ≤ 0.008 for all) for non-diabetic (tear volume dependent) than diabetic donors (tear volume independent), respectively. GGT activity per mm was 50% lower in T1 than T2 diabetics (P = 0.02). Higher tear GGT activity in non-diabetic than diabetic females (P ≤ 0.05) was due to higher GGT activity in the African American females. CONCLUSION: GGT activity was less in T1 than T2 diabetics, but comparable to non-diabetic corneas. Schirmer tear GGT activity in diabetic eyes was tear volume independent, less in T1 than T2, lower than in tear volume dependent, non-diabetic female eyes. Low cornea and tear GGT activity suggests loss of antioxidant potential and supports ocular antioxidant therapy for diabetic patients.

Age-related decrease in human corneal γ-glutamyltranspeptidase activity.

PURPOSE: To investigate age-related effects on human corneal γ-glutamyltranspeptidase (GGT) (ectoenzyme important to maintaining corneal hydration and antioxidant potential via glutathione recapture). METHODS: Age-related differences between total, endothelial, and epithelial GGT activity and endothelial cell density were determined for corneas from 29 donors (mean age, 53 ± 17 years; age range, 13-83 years). GGT activity was determined using a standard colorimetric assay based on the transpeptidation reaction. Corneal GGT localization and expression was determined by immunohistochemistry. RESULTS: Total corneal, endothelial, and epithelial GGT activities in the young (<50 years) donor corneas were 37% (P = 0.02), 44% (P = 0.001), and 36% (P = 0.06) higher, respectively, than in the senior (≥50 years) corneas. The age-related rates of decline for GGT activity were 1.0 unit per year for total cornea, 0.4 to 0.5 unit per year for endothelium, and 0.3 to 0.4 unit per year for epithelium. Notably, endothelial cell density in the young corneas was 14% (P = 0.001) higher than in the senior corneas declining about 100 cells per square millimeter per decade (0.3% per year). GGT activity per 10 endothelial cells decreased at about 0.2 units per year and GGT activity per 10 endothelial cells in the young corneas was 41% higher (P = 0.01) than in the senior corneas. Fewer immunoreactive GGT-positive epithelial cells were detected in senior cornea. CONCLUSION: The age-related loss of human corneal GGT activity was associated with reductions in endothelial and epithelial GGT activity, being because of reduced number of GGT-positive endothelial and epithelial cells and reduced GGT activity per endothelial cell.