Microscope-integrated optical coherence tomography-aided intraoperative diagnosis and management of peripheral tractional retinoschisis

Case

A 48-year-old male, diagnosed case of Eales’ vasculitis, presented with best-corrected visual acuity (BCVA) of hand movements with a near-total combined retinal detachment in the right eye (OD) and BCVA 6/9 in the left eye (OS). OD fundus showed fibrovascular proliferation (FVP) nasally at the equator and a retinal break located inferior to the FVP [Fig. 1a and b]. Swept-source optical coherence tomography (OCT) (Topcon Corp, Tokyo, Japan) showed a grade 1 epiretinal membrane (ERM) in both eyes (OU). Preoperative fluorescein angiography OCT was performed. The patient underwent 23-gauge pars plana vitrectomy (PPV) with ERM peeling OD. Intraoperatively, there was a need to perform relaxing retinotomy/retinectomy (RR) to subdue intraretinal stiffening. But RR was incomplete. A detailed assessment with intraoperative optical coherence tomography (iOCT) (RESCAN 700, iOCT prototype; Carl Zeiss Meditec, CA, USA) revealed a residual outer retinal layer adherent to the retinal pigment epithelium in the bed of RR with retinoschisis along the margins of RR [Fig. 2a–c]. Hence, RR was extended to the outer layer relieving the retinal traction [Fig. 3].

Figure 1.

Preoperative images. Ultra-wide field fundus imaging OD showing (a) combined retinal detachment with peripheral laser-induced chorioretinal scar and (b) showing fibrovascular proliferation causing traction (arrow)

Figure 2.

Intraoperative images. Intraoperative fundus image (a) showing the probable outer lamina of the retina over the retinectomy site (arrow) and the margin of the incomplete retinectomy confined only to the inner lamina. (Star) Intraoperative iOCT images showing (b) prominent outer lamina on iOCT (arrow) in the bed of the retinectomy site and (c) retinoschisis visible along the margins of the retinectomy (arrow)

Figure 3.

Postoperative images. One month postoperative ultra-wide field image OD showing an attached retina with a peripheral retinectomy (arrow)

Discussion

The importance of iOCT has been listed earlier by the PIONEER and the DISCOVER studies.[1,2] Here in our case, iOCT-guided peripheral assessment showed tractional retinoschisis (TR). Broad tissue beams bridging the retinal pigment epithelium and the retina were visualized along with narrow streaks connecting the inner and outer layers of schisis. TR has been found in tractional elevations in patients with diabetic retinopathy where the avascular retina is prone to split due to the centripetal pull of the posterior hyaloid.[3] Here, we suspect a similar mode of pathogenesis along with an additional centrifugal force caused by the chorio-retinal (CR) scar.

RR has shown to benefit cases where intractable traction prevents the reattachment of retina.[4] Here, RR was initially incomplete due to the unnoticed retinal split.

Conclusion

To conclude, iOCT over peripheral retina helped in identifying unnoticed peripheral retinoschisis and provided useful timely feedback to the surgeon.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.