Ladd Byron S, Fujii Gildo Y, Gupta Puneet, Jensen Patrick S, Kouzis Anthony, Rossi Juliana V, Barnes Aaron, De Juan Eugene
Microsurgery Advanced Design Laboratory, Doheny Retina Institute at Doheny Eye Institute, The Keck School of Medicine, University of Southern California, Los Angeles, USA.
Retina. 2003 Feb;23(1):76-9. doi: 10.1097/00006982-200302000-00012.
To develop and characterize an infusion cannula that reduces the intraocular jet forces created during fluid-air exchange.
A new infusion cannula was manufactured by adding a baffle 1.0 mm perpendicular to the distal opening of a 20-gauge infusion. The forces generated by the modified and standard cannulas were measured at a constant air infusion pressure of 50 mmHg by using a force sensor coupled to a schematic eye with eight radial positions from 0 degrees to 180 degrees along the circumference. Five different orientations relative to the baffle support of the modified cannula were evaluated at each position to assess the turbulent flow.
The standard cannula produced a maximum force of 0.14 mmHg at 180 degrees from the sensor. The modified cannula generated a maximum pressure of 0.017 mmHg at 67.5 degrees from the sensor. Overall, the force from the modified cannula was an order of magnitude less than the standard infusion cannula (P < 0.01).
The modifications of the new infusion cannula are passive with respect to its surgical performance. However, the additional baffle transforms laminar air currents into turbulent ones and allows dispersion of the jet forces, which should reduce barotrauma and desiccation of the retina during fluid-air exchange.
研发并表征一种能降低液体 - 空气交换过程中产生的眼内喷射力的输液套管。
通过在20号输液器远端开口垂直方向添加一个1.0毫米的挡板来制造一种新的输液套管。使用与模拟眼相连的力传感器，在50毫米汞柱的恒定空气输注压力下，沿着圆周从0度到180度的八个径向位置测量改良套管和标准套管产生的力。在每个位置评估相对于改良套管挡板支撑的五种不同方向，以评估湍流。
标准套管在与传感器成180度时产生的最大力为0.14毫米汞柱。改良套管在与传感器成67.5度时产生的最大压力为0.017毫米汞柱。总体而言，改良套管产生的力比标准输液套管小一个数量级（P < 0.01）。
新输液套管的改良对其手术性能而言是被动的。然而，额外的挡板将层流气流转变为湍流，并使喷射力分散，这应能减少液体 - 空气交换过程中视网膜的气压伤和干燥。
