Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada.
IRCCS Azienda Ospedaliero-Universitaria di Bologna, Italy.
Transl Vis Sci Technol. 2022 Dec 1;11(12):17. doi: 10.1167/tvst.11.12.17.
To develop and perform ex vivo testing for a device designed for semiquantitative determination of intracorneal dissection depth during big bubble (BB) deep anterior lamellar keratoplasty.
A prototype device connected to a syringe and cannula was designed to determine depth of intrastromal placement based on air rebound pressure emitted by a software controlled generator. Ex vivo testing of the device was conducted on human corneas mounted on an artificial anterior chamber in three experiments: (1) cannula purposely introduced at different depths measured with anterior segment optical coherence tomography, (2) cannula introduced as per the BB technique, and (3) simulation of the BB technique guided by the device.
A positive pressure differential and successful BB were observed only when the cannula was positioned within 150 microns from the endothelial plane. In all successful BB cases (21/40), a repeatable increase in tissue rebound pressure was detected, which was not recorded in unsuccessful cases. The device was able to signal to the surgeon correct placement of the cannula (successful BB) in 16 of 17 cases and incorrect placement of the cannula (unsuccessful BB) in 8 of 8 cases (94.1% sensitivity, 100% specificity).
In our ex vivo model, this novel medical device could reliably signal cannula positioning in the deep stroma for effective pneumatic dissection and possibly aid technical execution of BB deep anterior lamellar keratoplasty.
A medical device that standardizes big bubble deep anterior lamellar keratoplasty could increase the overall success rate of the surgical procedure and aid popularization of deep anterior lamellar keratoplasty.
开发并进行离体测试，以评估一种用于半定量测量大泡（BB）深层前板层角膜切开术中角膜内分离深度的设备。
设计了一种与注射器和套管相连的原型设备，用于根据软件控制发生器发出的空气回弹压力来确定间质内放置的深度。在三个实验中对该设备进行了离体测试：（1）套管故意置于前节光学相干断层扫描测量的不同深度处，（2）按 BB 技术引入套管，以及（3）在设备引导下模拟 BB 技术。
仅当套管位于内皮平面 150 微米以内时，才观察到正压差和成功的 BB。在所有成功的 BB 病例（21/40）中，检测到组织回弹压力的可重复增加，而在不成功的病例中则未记录到。该设备能够在 17 例中的 16 例中提示外科医生套管的正确放置（成功的 BB），在 8 例中的 8 例中提示套管的不正确放置（不成功的 BB）（94.1%的敏感性，100%的特异性）。
在我们的离体模型中，这种新型医疗设备可以可靠地提示套管在深层基质中的定位，以实现有效的气动分离，并可能有助于 BB 深层前板层角膜切开术的技术执行。
医学博士 Francesco D'Amico、医学博士 David R. Sliney、医学博士 Maria C. Montero、理学学士 Vivek G. Shetty
