Optical coherence tomography and congenital retinoschisis : three case reports

Congenital retinoschisis is an X-linked recessive inherited disease. It causes the splitting of the retina’s neurosensory layers from the remaining of the sensory retina, presenting itself as a “stellate” or “bicycle-wheel” maculopathy, vitreous hemorrhage and retinal detachment. We report three cases of congenital retinoschisis, two of them brothers. optical coherence tomography was used when evaluating the cases. It was impossible to differentiate retinoschisis from retinal detachment in one of the cases through optical coherence tomography due to lack of patient collaboration. We then performed laser photocoagulation to mark and follow-up the affected area.


C
ongenital Retinoschisis is an X-linked recessive inherited disorder.(3) Affected patients may present strabismus, nystagmus, peripheral retinoschisis, vitreous hemorrhage, vitreous membranes, retinal detachment (RD), "stellate" or "bicycle-wheel" maculopathy.Optical coherence tomography (OCT) helps in the evaluation and differential diagnosis between congenital retinoschisis and RD.Treatment is based on management of complications.Congenital retinoschisis has an unpredictable prognosis, being reported cases of regression, stabilization and late progression.

Case Reports Case 1
PBO, male, 11 years old, presented a diminished visual acuity in both eyes (oculus uterque -OU).Visual acuity was 20/200 in the right eye (OD) and 20/70 in the left eye (OS).Slit lamp biomicroscopy revealed peripheral retinoschisis in the inferotemporal quadrant reaching the inferotemporal vascular arcade and a pseudohole aspect maculoschisis OD (Figure 1).It also revealed small maculoschisis and peripheral vitreous membranes OS. (Figure 2) OCT showed cysts on the macular area, which coalesced to a bigger cyst in the foveal area OD (Figure 3) and a symmetrical presentation OS.These findings were consistent with Bilateral Macular Retinoschisis (BMR) Photocoagulation of the posterior edge of the right eye's Retinoschisis was performed to mark and follow-up the affected area.A control-OCT, performed one year later, showed no alterations.It was impossible to identify the marked area due to lack of patient cooperation.Ophthalmoscopy follow-up revealed no disease progression.

Case 2
EHCA, male, 23 years old, presented a diminished peripheral visual field and low visual acuity OD.Best corrected visual acuity (BCVA) levels of 20/200 OD and 20/30 OS.Ophthalmoscopy revealed vitreous membranes OU.Campimetry showed nonspecific alterations.OCT revealed BMR of symmetrical aspect OU. (Figure 4) LHCA, male, 15 years old, case 2 patient's brother, presented a diminished visual acuity OU.BVCA of 20/25 OU.Ophthalmoscopy revealed vitreous membranes, altered fovea appearance and beaten-bronze appearance of the macula.OCT showed BMR of symmetrical aspect OU. (Figure 5)   Congenital Retinoschisis is a rare, bilateral, asymmetric X-linked inherited disorder that presents itself on the first decade of life. (1,2)It affects primarily young males. (4,5)he estimated prevalence of the disease is 1:5000-25000 individuals (6) .The anomaly was identified in the Xp22 chromosome's gene XLRS1, causing more than 130 mutations.Therefore, there are many diverse clinical manifestations, even in the same family.(6)(7) The disorder results on the splitting of the retina's neurosensory layers from the remaining of the sensory retina. (1,8)he patients can exhibit strabismus, nystagmus or diminished visual acuity due to the maculopathy.(11) Some other observed signs are peripheral retinoschisismostly on the inferotemporal quadrant -and oval holes on the retinoschisis' inner layer, which originate vitreous veils. (1,2,6)he diagnosis is made by indirect binocular ophthalmoscopy.OCT can be of aid on the diagnosis of atypias and advanced stages of the disease, in which the late phenomena can make the diagnosis difficult.The OCT identifies different phases of the disorder: (a) isolated foveoschisis, (b) foveoschisis associated with lamellar cysts without a peripheral ophthalmoscopic disease, (c) foveoschisis associated to lamellar cysts and peripheral disease, and (d) foveoschisis associated to peripheral disease in the absence of lamellar cysts. (4,6,11)etinal detachment, pigmentary retinitis, Eales disease, sickle cell retinopathy, retinopathy of prematurity and Goldmann-Favre vitreoretinal degeneration and the Stellate non familial retinoschisis (12) are differential diagnosis of Congenital Retinoschisis.
The pathology's progression is fast during the first years of Treatment consists on the management of complications.Pars plana vitrectomy is recommended for persistent vitreous hemorrhage or RD, aiming to close the retinal fractures of the peripheral retinoschisis external layers.Laser photocoagulation or vitrectomy are indicated in cases of recurrent or non absorbing vitreous hemorrhage in patients with severe low visual acuity due to this cause. (1,2,10)Carbonic anhydrase inhibitors may be effective for cystic foveal lesions.10  This series of cases indicate the importance of OCT.Due to the early age of onset and consequent lack of cooperation, its execution may be difficult.It may have little value on peripheral retinoschisis, but it remains a useful tool to differentiate between retinoschisis and RDs that may harm the macula.

Figure 3 -
Figure 3 -OCT OD: Various cysts in the macular area situated on the inner nuclear and plexiform layers that suggest coalescence to a bigger macular cyst at the foveal area