Currently, phacoemulsification is the most common surgical technique used to treat cataracts world-wide. PCR is a common and frequent complication of this surgery. During I/A cortex, the incidence rate of PCR has been reported as 0.13–0.69% [6, 11]. According to our own experience, at a certain stage PCR was likely to occur in the I/A phase than in the phaco phase for surgery trainees [12]. Therefore, avoiding PCR is important for the entire I/A phase.
We tried to perform hydropolish before the I/A cortex, which was called the lens cortex removal assisted by hydropolish to improve the safety of the I/A cortex and avoid the occurrence of PCR. In this method of hydropolish, injection of ophthalmic viscoelastic device (OVD) and implantation of intraocular lens (IOL) were performed first. Further, I/A cortex and OVD together are performed.
Hydropolish is usually done for removing residual cortex after I/A cortex by rinsing with BBS [8]. As a previous study, we also found hydropolish could be done before I/A phase, and after hydropolish, the cortex could be removed easily [11]. The removal of cortex in the subincisional space is specifically challenging [13, 14]. Dewey has shown a cortex removal technique using the J-shaped cannula, which could be used for subincisional cortical removal [15]. However, because of the shape of J-cannula, the intraocular tissues may be hooked at the tip. In our technique, I/A cortex was done after hydropolish, injection of OVD and implantation of IOL, and the cortex in the subincisional space could be removed easily. In our surgery, hydropolish was performed just from the main incision, so the cortex in the subincisional space could not be rinsed directly. However, after injection of OVD and implantation of IOL, the cortex could be pushed from the centre to the capsular fornix, and can be easily removed by I/A. The IOL could protect the posterior capsule and avoid the occurrence of PCR. Sometimes, the loop of the IOL may suppress the cortex and cause difficulty in the cortex removal. Rotating the IOL could easily solve this difficulty. In addition, we had rinsed the cortex in the subincisional space by a side port. We did not find any difference on the cortex removal after the implantation of IOL. In our study, the IOL was one-piece hydrophilic IOL. In our clinical experience, all kinds of IOL could be fit for this method.
In our study, we found that the hydropolish time was different in both the groups. Before I/A cortex, hydropolish needed more time than hydropolish following I/A cortex. As with the existence of much cortex, hydropolish needs to rinse the central cortex, and then rinse the residual cortex on the posterior capsule. However, if hydropolish following I/A cortex is done, it just needs to rinse the residual cortex on the posterior capsule. The time of the entire procedure was shorter in group 1 significantly (P = 0.002). The main reason was that I/A cortex and I/A OVD were done in a single step. After hydropolish and implantation of IOL, I/A cortex was easily removed in group 1.
There are some limitations of this technique. First, some patients were not fit for this method, such as cataract after vitrectomy and hypermyopia. These patients were without sufficient vitreous support and after removing the nucleus, the anterior chamber could not collapse in most of them. Therefore, rinsing the posterior capsule was not easy. Second, hydropolish is not fit for polishing the anterior capsule.