Valved versus nonvalved cannula small-gauge pars plana vitrectomy for repair of retinal detachments with Grade C proliferative vitreoretinopathy

TRANSSCLERAL INCISION FOR PEELING SUBRETINAL PROLIFERATION TISSUE IN GRADE C PROLIFERATIVE VITREORETINOPATHY

PURPOSE

The purpose of this study was to investigate the clinical outcomes of an optimized method to clearly remove the subretinal proliferative tissue by transscleral puncture into the subretinal space in patients with grade C proliferative vitreoretinopathy without inducing retinal injury.

METHODS

This was a prospective clinical observation study. Eight consecutive patients who had undergone optimized vitrectomy surgery for retinal detachment complicated by grade C proliferative vitreoretinopathy were investigated. Subretinal proliferation was cleared by adding one additional scleral 23-gauge trocar under the detached retina at 9 mm to 10 mm from the limbus. After the sclera is pierced, the puncture knife changed its direction without touching the retina. 23-G intraocular forceps were used to remove the proliferation strand or membrane through the puncture channel.

RESULTS

Retinal reattachment was achieved in each case without a retinotomy. The mean best-corrected visual acuity was improved within the first 1 month ( P = 0.039) and remained stable at the following phase. There were no postoperative complications, such as reoccurrence of retinal detachment or proliferative vitreoretinopathy. No postoperative hemorrhage or hypotension was observed.

CONCLUSION

The satisfying results demonstrated the feasibility of this cost-effective, easy-to-follow, transscleral vitrectomy method in treating retinal detachment with grade C proliferative vitreoretinopathy.

Hybrid 23/27 Gauge Vitrectomy - Combining the Charm of 27G with the Efficacy of 23G

Background

Minimally invasive transconjunctival sutureless vitrectomy (MIVS) has evolved into the standard of care, smaller incisions thought to result in lower ocular surface trauma and shorter times to recovery. The currently most relevant limitations in macular surgery may be light intensity and 27G instrument stability. Therefore, we thought to compare standard 23 and 27G vitrectomy with a hybrid technique using one 23G and two 27G ports regarding surgical times and short-term outcomes.

Methods

This retrospective comparison included 90 single-center consecutive cases of eyes undergoing elective micro-invasive vitrectomy for epiretinal membranes or idiopathic macular holes between October 2017 and June 2018. The main criteria for the comparison were total surgical time as primary outcome parameter and treatment-demanding intra- and postoperative complications along with recovery of best-corrected visual acuity (BCVA) and central retinal thickness (CRT) from prior to surgery to 1 month thereafter as secondary parameters as independent parameters for the recovery from the pre-existing pathology and the surgical trauma.

Results

Surgical times were shorter with 23G and 23/27G compared to 27G (23G: 38.4±13.1; 27G: 48.1±15.3; 23/27G: 34.9±9 mins; p=0.0005) with no differences in BCVA and CRT outcomes. Switching from 27G to a larger port size was not necessary in any instance. Cryotherapy was applied in 15%, 30%, and 22.5% to suspected retinal pathologies, beyond these, in 5%, 0%, and 7.5% for retinal tears. Four postoperative retinal detachments occurred (4.4%), one in the 23G and three in the 23/27G group requiring re-vitrectomy.

Conclusion

In this exploratory case series, 23/27G hybrid vitrectomy, combining the advantages of 23G and 27G techniques, resulted in shorter surgical times without evident disadvantages. The combination with cataract surgery was unproblematic.

Proliferative Vitreoretinopathy: A Review

Proliferative vitreoretinopathy (PVR) is the most common cause for failure of rhegmatogenous retinal detachment repair and is characterized by the growth and contraction of cellular membranes within the vitreous cavity and on both sides of the retinal surface as well as intraretinal fibrosis. Currently, PVR is thought to be an abnormal wound healing response that is primarily driven by inflammatory, retinal, and RPE cells. At this time, surgery is the only management option for PVR as there is no proven pharmacologic agent for the treatment or prevention of PVR. Laboratory research to better understand PVR pathophysiology and clinical trials of various agents to prevent PVR formation are ongoing.