Lamellar ring- A nature’s guide for capsulorhexis in beginner surgeons

Dear Editor, Cataract surgical techniques, especially modern phacoemulsification, are challenging for resident or trainee surgeons and have a steep learning curve. Often many residents find it difficult and get anxious in performing cataract surgical steps, mainly capsulorhexis and nucleus management.[1] These days, we are equipped with many training tools in surgical skill labs, such as surgical simulators and animal eyes, before operating on patients. Even then, initial cases seem difficult during the capsulorhexis procedure while planning and performing a circular, 5–5.5 mm, well-centered, continuous curvilinear rhexis in resource-poor settings. There have been many studies pointing out the risk factors for poor outcomes or associated factors resulting in posterior capsular rent and vitreous loss in resident-operated cataracts.[2,3] Hence, there is no doubt that resident training should happen in a phased manner from wet lab simulators to animal eyes and then operating in human eyes. Case selection is also of utmost importance for residents, wherein initial cases must be easier cases with a lower associated risk for complications. We often encounter many cataracts with a visible ring of cortical nuclear differentiation. This ring itself is a nature’s guide for capsulorhexis, wherein image-guided systems are not available for capsulorhexis training. To our surprise, when we started observing these cases closely, there is a spectrum of cases with varying sizes, thickness, and continuity of rings. So, one may start with cases with clearly visible rings and then proceed to cases with faint and discontinuous rings [Fig. 1]. If the cortical nuclear ring is larger than 5–5.5 mm, then a smaller rhexis is made by following the track. If the ring is smaller, then rhexis should be larger and outside of the ring. Also, the hydro delineation is easier in these cases, wherein the cortico-nucleus junction is naturally wider, which is documented on intraoperative anterior segment optical coherence tomography [Fig. 2]. Similarly, during the initial stages of pediatric cataract surgical training, either zonular cataract or a nuclear lamellar cataract should be preferred over other morphological varieties.[4] These cases improve the confidence of residents during the early stages of training for performing capsulorhexis without rhexis runoff, resulting in better postoperative outcomes for the patient and less stress to both the trainee and the trainer [Fig. 1].Figure 1: Intraoperative images of adult cataracts with cortical-nuclear ring of varying sizes before (blue arrow) and after capsulorhexis (green arrow) (a-f) Pediatric zonular cataract before (blue arrow) and after capsulorhexis (green arrow) (g,h). (i) An adult cataract with a very large cortical nuclear ring (black arrow)Figure 2: Intraoperative anterior segment optical coherence tomography (iOCT) images showing visible delineation between the nucleus and cortex before commencing the surgery (white arrows). (a) shows a magnified view and (b) in lower magnification with a visible iris in the periphery (orange arrow)To conclude, while considering factors of cataract cases for trainee surgeons, cases with a prominent cortical nuclear ring, zonular, or lamellar nuclear cataracts should also be considered as a factor, especially for those residents in the early stages of training. Financial support and sponsorship: Nil. Conflicts of interest: There are no conflicts of interest.