Repairing peripheral nerve defects by vein grafts filled with adipose tissue derived stromal vascular fraction: an experimental study in rats.

BACKGROUND: There are many studies in the literature combining vein grafts with cell cultures, muscle, tendon, and nerve tissues, but none of them could replace isolated nerve grafts for nerve repair in clinical settings. There are studies in the literature indicating that adipose tissue derived stromal vascular fraction (SVF) enhances peripheral nerve healing. Considering these facts, an experimental study was performed in rats based on combining SVF with vein grafts for peripheral nerve defect repairs. METHODS: The study included 30 rats which were divided in three groups. In the first stage, an 8 mm nerve defect was created in tibial nerve of each rat. In Group 1, the defect was reconstructed with nerve graft, in Group 2, the defect was reconstructed with vein graft, and in Group 3, the defect was reconstructed with vein graft filled with SVF solution. After 3 months, the second surgical stage was performed and nerve biopsies were taken. Tissue samples were observed histopathologically. RESULTS: There were no statistically meaningful difference between nerve grafts, vein grafts and adipose tissue derived SVF- vein grafts combination groups considering myelin diameter and axonal diameter. Axon count was statistically superior in the nerve graft and study groups when compared to empty vein groups. CONCLUSION: In conclusion, our results support the usage of stromal vascular fraction-vein graft combination for peripheral nerve defect repairs.

Periocular metatypical cell carcinoma: clinicopathologic correlation, management, and follow-up in 35 patients.

BACKGROUND: To present the clinical characteristics and treatment outcomes in a relatively large series of patients with periocular metatypical cell carcinoma. METHODS: This is a retrospective study of 35 patients with periocular metatypical cell carcinoma, who were seen between January 2000 and December 2004 in Izmir Ataturk Research and Training Hospital, Turkey. The patients were histologically confirmed metatypical cell carcinoma with radiologic evidence of periocular region. The main outcome measures were patients' demographics, duration of tumour, clinical presentation, tumour site, treatment modalities, recurrence rate and tumour-related exenteration. Statistical comparisons between the nonrecurring group and recurring group were completed using the Cox regression analysis and the log rank test. Significance was determined for all statistical tests as pé 0.05. RESULTS: The median age of patients at time of diagnosis was 61 years. The most common site for metatypical cell carcinoma was medial canthus and lower eyelid region. The median follow-up for all patients was 18 months. The average length of time until recurrence was 13 months. Five of the 35 patients received adjuvant therapy to the primary tumour site after excision. Signs suggestive of orbital involvement included bone fixation of the mass, limitation of ocular motility and globe displacement. The early lack of diagnostic criteria for metatypical cell carcinoma created considerable debate and confusion regarding its diagnosis. We believe that once this diagnosis is made, the treatment modality should be individualized and chosen with consideration of the extent of orbital involvement, visual function, and the patient's general health.