Retinal detachments due to large-outer retinal tear in acquired retinoschisis managed with adjunctive combinations of microscope-integrated and wide-field optical coherence tomography

Abstract

This case series includes three consecutive cases who presented with retinal detachment (RD) in acquired retinoschisis due to giant outer lamellar tears. Preoperative widefield optical coherence tomography (WF-OCT) was used for diagnosis and intra-operative optical coherence tomography (iOCT) was used to confirm the extent of retinoschisis, identify borders of retinectomy and identify a safe area for drainage retinotomy. All eyes developed recurrent RD and required repeat surgeries. Learnings from the immediate failure of the first case guided our surgical planning with iOCT-assisted surgery in the next two cases leading to acceptable outcomes. Fellow eye required WF-OCT guided prophylactic laser barrage in two out of three cases. We concluded that preoperative recognition of giant outer layer lamellar tears in retinoschisis is crucial as these cases harbor poor anatomical prognosis and demand patient counseling. We found WF-OCT and iOCT to be very useful in understanding and management of these eyes.

Introduction

Retinoschisis is defined as “a split in the neurosensory retina.”[1] Senile retinoschisis is often asymptomatic and nonprogressive. It is a rare disease characterized by abnormal separation of retinal layers, typically at the outer plexiform layer which leads to the creation of an inner layer and an outer layer.[2] These eyes often harbor clinically insignificant tiny inner retinal breaks which, despite being in contact with the vitreous, do not lead to retinal detachment (RD) as there is no defect in the outer layer to allow seepage of fluid within the potential subretinal space.[3] RD generally develops due to retinoschisis when there are breaks in both inner and outer retinal layers as this would allow liquified vitreous to access the subretinal space.[2] However, such an RD has very slow progression if at all, is accompanied by features of chronicity and will almost never present with sudden-onset vision loss.

Observation has remained the primary mode of management in cases of senile degenerative retinoschisis, even when present posteriorly. Very rarely patients would need surgery for a RD, and this happens in only 0.05% of such cases mandating treatment.[4] In such situations, vitrectomy with endolaser, scleral explant, tamponade agent, and even retinectomy to deal with proliferative retinopathy can be needed.

Herein, we describe three patients with senile retinoschisis who presented to us with an unusual sudden onset “acute” RD related to degenerative retinoschisis. All three cases had an unusual feature of giant outer layer lamellar retinal tear along with multiple inner retinal holes. We used preoperative widefield and intraoperative optical coherence tomography variedly (WF-OCT and iOCT) during surgeries in these three cases to understand the pathology better, manage the fellow eye, and customize surgical technique to each patient. These cases have been presented in the chronological order of their presentation to our hospital, and management of these cases evolved with our increasing experience.

Case Reports

Case 1

Our first case was a male in his 60s who presented with complaints of decreased vision right eye (OD) for 2 weeks. He was referred to as a case of “acute” RD. OD visual acuity was hand motions close to face (HM). OD anterior segment examination revealed early cataractous changes. Fundus examination revealed temporal retinoschisis along with multiple inner layer holes and a giant outer lamellar tear causing a subtotal RD involving the macula [Figure 1a and b]. The giant outer lamellar retinal tear seemed to have wrinkled margins with proliferative vitreoretinopathy (PVR) changes. Left eye (OS) examination revealed normal fundus. OD pars plana vitrectomy (PPV), endolaser, and silicone oil injection (SOI) were performed. Intraoperatively, the absence of posterior vitreous detachment (PVD) was noted using intravitreal triamcinolone. RD was drained using a superior drainage retinotomy. The inner layer of the retinoschisis was spared at this juncture, and the giant outer lamellar tear and inner layer holes were treated with laser retinopexy. The retina was completely flat under oil at the end of surgery. Two weeks following the surgery, there was a recurrent macular and inferior RD. A repeat surgical intervention was urgently planned where iOCT was utilized which showed the grossly attached area of the giant outer lamellar tear [Figure 1c]. Inner retinal layer retinectomy was performed under perfluorocarbon liquid using iOCT as a guide to localize the area of retinoschisis, followed by peeling of additional membranes. Endolaser retinopexy at the retinectomy margin (continuous mode) and drainage retinotomy (repeat mode), and later SOI was done [Figure 1d]. The patient did well on postoperative follow-up maintaining visual acuity of 20/200 with retina attached under oil until 2 months. The patient was lost to follow-up thereafter.

Figure 1.

First case: (a) Fundus photo at presentation showing retinal detachment with multiple inner retinal holes (blue arrows) and giant outer lamellar tear (demarcated by blue circles) in the area of retinoschisis, (b) Intraoperative photo confirming giant outer lamellar tear and multiple inner retinal holes. A large retinal vessel transversing near the giant outer retinal tear suggesting retinoschisis is seen (arrow), (c) Intraoperative optical coherence tomography during the second surgery showing grossly attached giant outer lamellar tear (arrowheads). The horizontal scan shows the detached edge, whereas the vertical scan shows attached edge. The vertical scan is also able to identify the actual disjunction between detached normal retina and giant outer lamellar tear (arrow), (d) Postoperative fundus photo showing attached retina under oil with retinectomy margins and laser marks

Case 2

Our second case was a 73-year-old male who presented to us with complaints of diminution of vision in OD for 3 weeks and had been advised surgery for “acute” RD. Visual acuity was HM. Anterior segment examination was unremarkable with posterior chamber intraocular lens in situ. The eye was grossly hypotonous and fundus examination revealed subtotal RD with choroidal detachment. Preoperative topical and posterior subtenon steroids were administered. Subsequently, intraocular pressure normalized with partial regression of the choroidal detachment and a giant outer lamellar tear with retinoschisis could be visualized in the inferotemporal quadrant [Figure 2a]. OS examination and WF-OCT revealed senile retinoschisis in temporal quadrants with localized subretinal fluid, and attached outer retinal layers in the periphery [Figure 2b]. PPV, endolaser, and SOI were planned for OD. Intraoperatively, the temporal schitic retina was noted with wrinkled giant outer lamellar tear and multiple inner retinal layer breaks [Figure 2c] mimicking the findings of the first case. Macular pucker along with membranes were visibly present in all quadrants indicating PVR changes. Guided by our previous experience with the similar surgical scenario, temporal inner retinal layer retinectomy was performed in this case. Drainage retinotomy was made superiorly to drain the RD. Endolaser was applied to retinectomy edges in continuous mode and to drainage retinotomy and inferior lattices in repeat mode. The retina was attached intraoperatively under oil. Postoperatively, the patient did well with best corrected visual acuity of 20/200 and attached retina. However, at 2 months of follow-up, the eye developed PVR-related inferior RD [Figure 2d]. A secondary surgery was performed with membrane peeling around the retinectomy margins and at macula followed by additional endolaser at retinectomy margins in continuous mode along with silicon oil exchange. The patient maintained his vision at 1^st day of surgery, and the retina has remained attached under oil until a follow-up of over a year. However, hypotony developed in relation to acute endophthalmitis, that was managed with intraocular antibiotics. Barrage laser treatment of the fellow eye’s retinoschisis was also performed after discussion with the patient and family.

Figure 2.

Second case: (a) Fundus photo showing retinal detachment and Giant outer lamellar tear with wrinkled margins (arrowhead) in the area of retinoschisis. Holes in the inner retina overlying the giant outer lamellar tear are noticeable (arrows). B scan ultrasound shows retinal detachment and choroidal detachment, (b) Wide-field optical coherence tomography (OCT) of the fellow eye at presentation. The green line indicates the area of the B scan of OCT. The arrowheads indicate the retinal detachment encroaching towards the posterior pole, while the arrow indicates the peripheral attached outer retinal flap, (c) Intraoperative photo showing giant outer lamellar tear (arrowheads) and multiple inner retinal layer holes (arrows), (d) Postoperative photo showing with inferior retinal detachment under oil

Case 3

Our third case was a male in his early 50s who presented with complaints of reduced vision OS for 7 days and had been advised surgery for a “acute” RD. Visual acuity OS was counting fingers close to face. Fundus examination revealed a giant outer lamellar tear visible in the temporal quadrant with PVR changes and wrinkled margins of the giant outer lamellar tear [Figure 3a]. WF-OCT of OS confirmed retinoschisis with a macula-off subtotal RD [Figure 3b]. Fundus examination of OD revealed peripheral retinoschisis in inferotemporal quadrant. He was appropriately counseled for the need for repeat surgeries given our previous experiences, and surgery was planned with iOCT as an adjunct. PVD was absent and had to be induced using intravitreal triamcinolone. Before performing the inner retinal layer retinectomy, iOCT was used to locate the margins of the retinal splitting and to define the area of the retinectomy as well as a retinal splitting-void area for drainage retinotomy [Figure 3c and d]. Endolaser was applied in continuous mode at the retinectomy margins and in repeat mode at the edges of drainage retinotomy. Postoperatively, the patient improved to visual acuity of 20/80 OS with attached central retina. However, this patient also developed PVR-related recurrence of inferior RD [Figure 3d]. A repeat surgery was performed, and belt buckle was placed this time to support retinal contracture. The retinectomy margin was extended during the second surgery and endolaser applied in continuous mode along with silicone oil exchange. Six months later, silicone oil was removed, and the retina has remained attached with a visual acuity of 20/100. The margins of retinectomy were reassessed for retinoschisis using iOCT at the time of oil removal.

Figure 3.

Third case: (a) Fundus photo showing retinoschisis with the macula-off retinal detachment and giant outer lamellar tear (demarcated by circles); the inner flap is also noticeable (arrows), (b) Wide field-optical coherence tomography (OCT) showing retinoschisis involving the macula (arrow). The location of B scan is indicated by the green line over the accompanying fundus photo, (c) Intraoperative OCT shows identification of a schisis-free area where the drainage retinotomy was made (arrow), (d) Vertical scan of the intraoperative OCT is able to identify the edge of the giant outer lamellar tear within the area of retinoschisis (arrow), (e) Postoperative fundus photo showing centrally attached retina with sealed DR site and proliferative vitreoretinopathy related recurrence of inferior retinal detachment

The results following the second intervention in the first case guided our surgical planning in the next two cases where iOCT-guided inner layer retinectomy was performed within the primary surgery itself. This allowed for an immediate anatomical success with primary surgery, though the success lasted for a short-term necessitating repeat elective surgeries due to PVR. These cases seem to have poorer prognosis as such with a tendency to develop PVR and recurrent RD, warranting multiple surgical interventions.

Discussion

Management of senile retinoschisis primarily involves observation.[2] However, patients presenting with progressive RD associated with retinoschisis require surgical intervention in the form of scleral buckling (SB), PPV, or a combination of both. Given the rarity of the condition and limited available literature, there is no consensus on the preferred surgical approach, and the management strategy must be tailored as per the patient’s presentation.[5]

Inner layer retinectomy during PPV has been previously described in cases of RD associated with juvenile retinoschisis.[6] The maneuver involves cauterizing the inner retinal vessels in the region of retinoschisis followed by the destruction of the retinal tissue at high cut rates while controlling the bleeding. Inner wall retinectomy works by releasing the mechanical traction on the retina thereby allowing it to reattach.[6] A study assessing the advantage of inner layer retinectomy in cases with RD associated with juvenile retinoschisis showed that among eight eyes that initially underwent inner layer retinectomy, only one required subsequent retinal surgery for postoperative complication. Four eyes that did not undergo initial inner layer retinectomy required subsequent repeat intervention for recurrent RD.[7] Stem et al. studied 37 eyes with retinoschisis-related RD managed with various surgical procedures retrospectively reporting a single surgery success rate of 65%. Recurrent RD in six of the 13 cases (46%) was attributed to PVR. The authors had performed inner layer retinectomy in five out of 37 cases in their series but no recommendation was made for the same.[8] Like our patients, Sulonen et al. reported five cases of RD caused by giant posterior breaks in the outer layer of degenerative retinoschisis. However, only one of their case had inner holes, and none was treated with retinectomy. The authors suggested SB alone might not be an adequate treatment for such cases due to the posterior location of large breaks.[9]

All the three patients of the current series presented to us with symptoms of a presumed “routine/acute” RD; it was only through a detailed fundus examination that we could suspect the presence of multiple inner retinal holes along with a concomitant giant outer lamellar tear in retinoschisis inflicted retina. To our knowledge, these giant outer lamellar tears are not well documented in the literature. Adjunctive use of preoperative WF-OCT helped in confirming the presence of these giant outer lamellar tears along with retinoschisis as the cause of the disorder in the fellow eye of the second and affected eye of the third patient. These cases did mimic PVD-related acute RD clinically, and as the attending clinician, it is imperative to understand the reduced chance of primary anatomical success as against a typical RD. In the first case, the inner retinal layer was initially spared as we could not anticipate a failure, being our own first experience. Even macular attachment could not be achieved within an early postoperative period in the first patient. iOCT was then applied in the second surgery, which guided us to the grossly attached giant outer lamellar tear and the limits of the inner layer retinectomy, allowing successful surgery. Learning from the first case, we performed similar steps in the next two cases and achieved acceptable results in early postoperative periods. iOCT was of great utility in the third case in determining the limits of retinectomy margins of retinoschisis-involved areas and also performing drainage retinotomy in a “schisis-free” retinal area.

With these unique experiences, we believe that the giant outer lamellar tears developed due to an increasing accumulation of fluid in the peripheral schitic cavity. This led to chronic stretch-related tangential force on the outer wall of the cavity, culminating in its thinning and the ultimate development of the giant outer lamellar tear. The tear gets its shape resembling that of a horseshoe tear (HST) due to the zipping action of stretch-related tangential forces while there is the absence of flap seen in a true HST as there is the absence of PVD in these cases. This phenomenon was noted in the fourth case of the series by Sulonen et al. where the giant outer lamellar tear was seen to grow in size encroaching toward the posterior pole.[9] As seen in the fellow eye of the second case [Figure 2b] and fifth case reported by Sulonen et al., initially, the giant outer lamellar tear remained attached but subretinal fluid started accumulating at the margins causing progressive RD. Because of limited access to the vitreous fluid in relation to the smaller inner retinal holes, the further pathogenesis was likely slow, driven by the development of PVR at the edges of the giant outer lamellar tear and within the “chronically” detaching peripheral retina.[10] Indeed, all the three cases showed definite wrinkling of margins of the giant outer lamellar tear [Figures 1–3]. Stem et al. too reported extensive PVR in their cases as discussed above.[8] However, there seems to be a limited role of vitreous traction in the formation of these giant outer lamellar tears as PVD was absent in two out of three cases. Being a slow process, PVR continued to develop around the giant outer lamellar tears and within the neural retina, and upon detachment of the giant outer lamellar tear, subretinal fluid increased suddenly causing macular detachment and presentation as an “acute” RD.

This chronic nature of this disorder, despite “acute” symptoms, must be explained to the patient and appropriate counseling done about the expected results.

To conclude, giant outer lamellar tears can develop in cavities of senile retinoschisis. Detailed fundus examination should be done in suspicious cases along with OCT-based imaging. Patients present when PVR has already developed in the peripheral retina and they need to be informed about the poor anatomical prognosis of primary surgery, and the surgeon should consider adopting an aggressive approach to account for the PVR. A combination of WF-OCT and iOCT helps to manage such cases as well as their fellow eyes. WF-OCT can serve as a valuable adjunct to detailed fundus examination in diagnosing this condition completely, and iOCT can help as a guide to surgical steps by defining its limits.

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.

Conflicts of interest

There are no conflicts of interest.

Funding Statement

This study was financially supported by Hyderabad Eye Research Foundation, Hyderabad, India.