ILPCR is rare and needs to be well-recognized clinical phenomenon. It was easy to be ignored as a simple traumatic cataract case because the lens became entirely opacity with intact suspensory ligament. It was always recognized to be simple case and had no suitable surgery management. Once the broken posterior capsule was found unexpectedly during the operation, extra solutions had to re-plan or be searched for. But after analyzing the six ILPCR cases, their characteristics were outstanding. The particular clinical findings of ILPCR were loose, translucent and flocculence-like cortex near the level of posterior capsule, faster development of cataract and greater incidence happened in the young people. But the ruptures were difficult to judge only by the silt-lamp biomicroscopy examination. With the help of UD (7 ~ 10MHz), the work became easier and the landmark appeared that the posterior capsular waveforms of the lens were interrupted. And some cloddy strong echo/flocculent weak echo were captured at the lens-vitreous interface. There was definite hint which the case had sustained severe traumatic cataract with ILPCR. Thus, the following preparation must be considered. The operation design included 4.5–5.0 mm CCC, phacoemulsification, anterior/posterior segment vitrectomy of the dropped remnant with IOL implantation in the ciliary groove during Phase I or II. Just like our planning, the prognosis of all six cases were satisfactory.
The ILPCR case was opportunistic due to some reasons. It was caused by a sudden force on the eyeball, especially happened in healthy and younger people because of the special anatomical feature of the interface between lens and vitreous. This was coincident with Liu and Tabatabaei’s observation [8, 9]. Specifically, in the youth, the vitreous appeared gelatinous, nearly spherical, with flat front surface. Except from the front portion, it could support the eyeball wall, absorb and redistribute external pressure, and alleviate the injury. The front surface was tightly coherent. But everything would be gradually loosened with age. Close to the lens, there was shortage of supporting and negligible buffer. Then, the lens and vitreous had different components and properties. After the sudden force on the eyeball, which was rapidly conducted along the axis of the eyeball, obvious change was observed in the interface between posterior capsule and anterior vitreous surface. Hence, the extruded strain was the same, while the resultant stress was very different. Given the external pressure concentration, the posterior capsule was stretched and fluctuated around the equator port. The thinnest position, only 4 µm, posterior polar, which was especially denied effective support by the vitreous and faced sudden tension, was susceptible to rupture. This was identified in the clinical cases, which often showed rupture around the posterior pole. Occasionally, the lens mistakenly looked tapered through the posterior capsule break, thus giving a false impression of an intact posterior capsule in most cases. Therefore, accurate diagnosis was very important for proper design and decision of the operation in order to achieve ideal results.
We first reported the use of UD (7 ~ 10MHz) to judge the appearance of ILPCR and decide on the treatment plan. According to anterior segment OCT, Scheimpflug and UBM imaging, they failed either to accomplish on a serious opaque media case or only to show the anterior segment imaging. UD conquered the shortcomings. Meanwhile, B-scan, which was commonly used in detecting the situation of traumatic cataract, supplying some information about the posterior segment, but was insufficient for precise details of interface between lens and vitreous. The probe of B-scan is fixed of 10 MHz to focus the object. The distance of B-scan is equal to the diameter of the equator. Hence, the direction of the probe had to changed drastically or the patients need to move their eyeballs in order to bring the lesion picture. Based on clinical experience, there were three requirements to obtain good quality picture in clinics: first, the lesion ultrasonogram should be in the center; next, the ultrasonogram should be vertical to the checked surface; and finally, adequate strength should be maintained and lower decibel should be applied to obtain optimal resolution images. UD had all advantages. It had full scan range around eyeball not to ask patient to match up. With variable probe frequency (3-13MHz inside eyeball), it was enough lower decibel to detect the object at remarkable axial minimum resolution (0.04-0.08mm). Besides, UD could supply better details and higher quality picture because of 256 gray-scale. So, this study had shown that UD (7 ~ 10MHz) was more appropriate than B-scan and others because of more convenient and accurate properties.