Our study demonstrated that postoperative BCVA and incidence of RRD did not differ between anterior vitrectomy or PPV in Yamane’s technique for patients with crystalline lens dislocation. Spontaneous PVD occurred in about two-thirds of patients with crystalline lens dislocation. Total vitrectomy with induction of PVD and laser photocoagulation of intraoperative retinal breaks and lattice degeneration don’t preclude the primary IOL fixation with Yamane’s technique and seems not to increase the risk of postoperative retinal detachment.

Our study showed high proportion (10.7%) of PURH/D in patients with crystalline dislocation. The common causes of crystalline dislocation include Marfan syndrome, ocular trauma and high myopia, which also predispose the patients to retinal breaks/lattice degeneration. One retrospective study of 40 eyes with vitreolensectomy in Marfan Syndrome [8] reported that seven eyes developed retinal detachment at baseline and the postoperative incidence of retinal detachment was 6%. Preoperative fundus evaluation helps to find out these retinal weak areas, while might be hindered by the mature cataract, luxated lens or opacities of other refractive media. Previous research also reported [9] that retinal breaks occurred in approximately one-third of patients with traumatic crystalline lens dislocation and were difficult to observe pre-operation. The pars plana approach has advantages over the trans-limbal approach in that retinal pathology may be treated directly and vitreous removal can be more complete with reduced tractional forces.

Anterior vitrectomy is commonly used by cataract surgeon in circumstance of complicated surgery. Although not as a routine procedure in anterior vitrectomy, peripheral retinal examination does offer us a second chance to find and seal the retinal breaks/degeneration without no further sequela. To lower the incidence of RD after adult cataract surgery in myopic patients, Fan et al. [10] recommended preoperative, intraoperative, and postoperative comprehensive fundus evaluation and laser treatments for suspicious lesions. Therefore, we advocate a similar approach of intraoperative fundus examination, especially in patients with anterior vitrectomy or any other procedures as long as the vitreous was disturbed.

Our series includes the first case report combining YAMANE technique with ILM flap technique to treat patients with crystalline lens subluxation and macular hole. According to our early surgical experience, full thickness closure of macular hole and stable intrascleral fixation of IOL could be achieved in one surgery. Combined with the previous discussion, retinal break/degeneration in crystalline lens dislocation, even macular hole, which could be managed with PPV, doesn’t preclude the primary implantation of IOL with YAMANE’s technique.

As proven with TA staining, spontaneous PVD happened in about two-thirds cases of crystalline lens dislocation in Group PPV, and PVD induction was performed for the rest cases. Comparison between patient with or without PVD showed that younger age, Marfan Syndrome, retinal break/lattice degeneration are indicators of attached posterior hyaloid. As is well known, both the degree of vitreous liquefaction and the prevalence of PVD are age-related [11]. The relative younger age in patients with retinal break/degeneration helps to explain the difference. Ripandelli et al. [12] showed that after cataract surgery, PVD occurred in 77.6% and 87.2% of emmetropic eyes without preoperative lattice degeneration and with lattice degeneration, respectively. Postoperative PVD-induced retinal breaks are associated with increased risk of RRD, which increases multiple folds in eyes having lattice degenerations. To guard against postoperative RRD, attached hyaloid and retinal break/degeneration are indications of PPV for patients with YAMANE technique in our surgical center.

There is still no consensus on preservation or removal of posterior hyaloid in vitreolensectomy. As reported in the study of vitreolensectomy in Marfan Syndrome in 2000 [8], all patients had a complete vitrectomy with removal of the posterior hyaloid face. Other researchers suggested that preservation of posterior hyaloid attachment during vitreolensectomy for crystalline lens dislocation was associated with fewer iatrogenic retinal breaks [8]. In 2020, the largest study in India evaluated the incidence, characteristics, and surgical outcome of RRD after PPV and sutureless SFIOL [5]. The induction of posterior vitreous detachment (PVD) was also not done in any of the cases. The overall incidence of postoperative RRD in their study cohort was 1.7% [5], which is similar to that reported in previous literature with sutured SFIOL [13,14,15] and in macular surgery [16, 17]. Yet it cannot be neglected that postoperative progression of PVD and peripheral retinal breaks/lattice degeneration leave the patients at high risk of RRD. That’s why we insist that PVD induction is mandatory in PPV——retinal break/degeneration is not a problem, untreated one is.

Our series includes the first case series of sutureless intrascleral fixation of IOL with Yamane technique in pediatric patients with ectopia lentis. Previous research [18] already reported the safety and efficacy of sutureless intrascleral fixated posterior chamber IOL in children with crystalline lens dislocation. Another study comparing the sutured and sutureless fixation of IOL in children suggested that both methods were suitable for the rehabilitation of pediatric aphakia [19]. Anterior trans-limbal approach of vitreolensectomy is preferred in our study for children with crystalline lens dislocation for the following considerations. Infants and children have smaller eyes with different surgical landmarks compared to adult eyes. The posterior trans pars plicata/plana technique can only be considered if the surgeon can safely introduce the instruments without causing an iatrogenic retinal break. PVD is not recommended in children with firmly adherent posterior vitreous like ROP. Forceful creation of a PVD is not only challenging but also carries a high risk of inducing retinal tears [20]. P Sen et al. reported that the incidence of postoperative RRD was 5.7% in children who underwent PPV with sutured scleral-fixed IOL [21]. Sumita et al. [22] reported a 5.5% risk of RD for the first 10 years after cataract surgery in children with no known ocular and systemic anomalies. The risk significantly increases in a male, myopic, and intellectual disabled child. However, PPV might be the reasonable option for children with posterior dislocation of crystalline lens in the vitreous cavity. The need for regular and long-term follow-up after pediatric cataract surgery emphasized in their conclusion is also applicable for children with crystalline lens dislocation.

Although the study is limited by its retrospective nature and small numbers, it brings forth certain surgical aspects: both anterior or pars plana vitrectomy are applicable in YAMANE technique for crystalline lens dislocation with no significant difference in postoperative visual recovery or surgical complications. Incidence of retinal breaks/lattice degeneration was 10.5% in patients with crystalline lens dislocation and spontaneous PVD occurred in about two-thirds of these patients. For pediatric patient with crystalline lens dislocation, anterior vitreolensectomy is preferred with primary YAMANE’s IOL fixation. For adult patients, Preoperative evaluation should focus on the PVD status and peripheral retinal search for potential retinal degeneration/break. PPV is reserved for patients with posterior dislocation of crystalline lens, attached posterior hyaloid (PVD-) and retinal degeneration/break. Intraoperative retinal examination under chandelier illumination or BIO should not be omitted in both anterior vitrectomy and PPV. Routine periodical follow-up might be beneficial for early detection and management for postoperative retinal detachment.