VITREOUS DYNAMICS
2008; Lippincott Williams & Wilkins; Volume: 28; Issue: 2 Linguagem: Inglês
10.1097/iae.0b013e318158e9e0
ISSN1539-2864
AutoresOctaviano Magalhães, Lawrence P. Chong, Charles DeBoer, P. Bhadri, R. Kerns, A. Barnes, S. Fang, Mark S. Humayun,
Tópico(s)Vascular Malformations Diagnosis and Treatment
ResumoTo evaluate porcine vitreous flow and balanced saline solution (BSS) flow rates in different vitrectomy systems.Porcine vitreous was obtained within 24 hours of slaughter. A high-speed (2 samples/s) balance, precise to 0.01 g, was used. Variable cut rates and vacuum pressures were analyzed in vitreous and BSS. The vitreous was labeled with glass microspheres and triamcinolone acetonide. A high-speed (400 frames/s) camera was used to record cutting for each condition.For all cutters, there was no vitreous flow at zero cut rates (off). In 25-gauge cutters, at 500 mmHg of vacuum, the electric cutter produced higher average flow rates at high cut rates (600 cpm, 0.004 mL/s, and 1500 cpm, 0.013 mL/s) than pneumatic, which demonstrated a decreased flow at speeds higher than 1000 cpm (1000 cpm, 0.015 mL/s, and 1500 cpm, 0.006 mL/s). The percentage of vitreous flow rate/BSS flow rate in different aspiration and cut rates showed an ascending curve. This demonstrates evidence of flow obstruction in 25- (all cut rates), 23- (all cut rates), and 20-gauge (all cut rates). Flow obstruction and surge movements were seen in the high-speed videos.The vitrectomy systems each illustrate different performances of vitreous removal. The physical characteristics of vitreous resulted in nonuniform flow in all vitreous cutters.
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