Consultant, Child Sight Institute, Jasti V. Ramanamma Children's Eye Care Centre, L. V. Prasad Eye Institute, Hyderabad, Telangana, India.
Director, Child Sight Institute and Centre for Technology Innovation, L. V. Prasad Eye Institute, Hyderabad, Telangana, India.
Indian J Ophthalmol. 2022 Sep;70(9):3431. doi: 10.4103/ijo.IJO_903_22.
Posterior lenticonus is a congenital condition characterized by the thinning and bowing of posterior lenticular capsule. Cataract develops when normal intra-lenticular pressure bulges the posterior capsule at the circumscribed portion of inherent thin posterior lens capsule, leading to derangement of lamellar lens fibers. This condition poses a surgical challenge as the presentation varies from thin, bulging posterior capsule to large, pre-existing posterior capsular dehiscence.
This video highlights the tips for the surgical management of various scenarios of posterior lenticonus.
In this video, tips for surgical management of various scenarios of posterior lenticonus are illustrated. Intraoperatively, ruptured posterior capsule is suspected by the presence of a fish-tail sign. The anterior capsulotomy is relatively easier in a flatter anterior lens capsule, owing to reduced intra-lenticular pressure. Hydro-dissection is avoided to prevent extension of pre-existing posterior capsular dehiscence or creation of rupture in a thinned-out capsule. The peripheral lens cortex aspiration is initiated first, followed by in each quadrant. In a presence of ruptured posterior capsule by vigilant inspection at this stage, the surgeon should change the direction of lens matter aspiration by aspirating the central lenticular matter first, followed by peripheral cortex like "inside-out". In absence of posterior capsule dehiscence, peripheral cortex is aspirated first, followed by central lens matter aspiration like "outside-in". Adequate anterior vitrectomy is performed until there are no vitreous tags.
In the presence of pre-existing posterior capsular defect, the lens matter is aspirated from the center (inside-out), whereas in the absence of capsular defect, the lens matter is aspirated from the periphery (outside-in).
后发性白内障是一种先天性疾病，其特征是后晶状体囊变薄和弯曲。当正常的晶状体内部压力使后晶状体囊在固有薄后晶状体囊的局限性部分向外膨出时，白内障就会发生，导致板层晶状体纤维紊乱。这种情况给手术带来了挑战，因为表现从薄的、向外膨出的后晶状体囊到较大的、预先存在的后晶状体囊破裂都有。
本视频重点介绍了各种后发性白内障病例的手术处理技巧。
在本视频中，演示了各种后发性白内障病例的手术处理技巧。术中，如果存在鱼尾征，就怀疑后晶状体囊破裂。由于晶状体内部压力降低，在前晶状体较平坦的情况下进行前囊切开术相对容易。为了防止预先存在的后晶状体囊破裂或在变薄的囊上造成破裂，应避免水分离。首先开始进行周边晶状体皮质抽吸，然后再按每个象限进行抽吸。在这个阶段，如果通过仔细检查发现后晶状体囊破裂，外科医生应通过首先抽吸中央晶状体物质，然后像“从内到外”一样抽吸周边皮质来改变晶状体物质抽吸的方向。如果没有后晶状体囊破裂，应首先抽吸周边皮质，然后像“从外向内”一样抽吸中央晶状体物质。应进行充分的前玻璃体切除术，直到没有玻璃体残端。
在存在预先存在的后晶状体囊缺陷的情况下，从中心（从内到外）抽吸晶状体物质，而在没有晶状体囊缺陷的情况下，从周边（从外向内）抽吸晶状体物质。
