Bilateral angle closure glaucoma with retinitis pigmentosa in young patients: case series

A 53-year-old female presented with 10 days history of blurry vision in the left eye. She had a family history of RP. On examination, the best-corrected visual acuity (BCVA) was 20/63 OD and only light perception OS. Intraocular pressure (IOP) was 19 mmHg OD and 33 mmHg OS for the first visit, and rising to 27 mmHg OD and 37 mmHg OS one week later, respectively. Pigmentary keratic precipitates (KP), Tyndall phenomenon, dilated pupils with no light response, narrow peripheral anterior chamber (PAC) with Van Herrick (VH) grade 1, and slight lens opacification were observed in bilateral eyes. The presence of osteoblast-like pigmentation in the inferior peripheral retina OU was observed (Fig. S1). The cup to disc ratio (CDR) was nearly 0.5 OD and 0.6 OS (Fig. 1A). No significant abnormalities were evident on the macular optical coherence tomography (OCT) of both eyes (Fig. 1B). The right eye had a visual field defect with retention of a small central and inferotemporal island, while no residual visual field existed in the left eye (Fig. 1C). Gonioscopy of both eyes revealed iridotrabecular synechia in full-circumferential range. A remarkable reduction in a- and b-wave amplitudes was seen in ff-ERG (Fig. S2). We applied genetic testing to the patient and identified a novel single nucleotide homozygous, transversion mutation (c.1618 C > T) of exon 5 in the ZNF408 gene (Fig. 1E). Both eye received two times daily topical beta-blocker (0.5% timolol), two times daily carbonic anhydrase inhibitors (0.15% brinzolamide), three times daily topical alpha-2 agonists (0.2% brimonidine tartrate) and one times daily travoprost (0.004%). But the left eye still had uncontrolled IOP and consequently undergoing transscleral cyclophotocoagulation (TCP). IOP in the right eye remained well-controlled with topical anti-glaucoma medications for ten months, and became elevated and progressively worsened to a peak of 43 mmHg. Hence, combined cataract surgery, trabeculectomy and the Irido-zonulo-hyaloid-vitrectomy (IZHV) were performed in the right eye. The postoperative anterior segment was kept in a stable condition (Fig. 1D), with BCVA improving to 20/28 OD, and IOP was maintained normal during a 2-year follow-up.

A 54-year-old female presented with a 10 days history of painless visual loss in the right eye. She was otherwise systemically well and had no significant family history. The BCVA was 20/80 OD and 20/40 OS. Goldmann applanation tonometry (GAT) revealed an IOP of 38 mmHg OD and 14 mmHg OS. The depth of PAC was VH grade 1 OU. The pupil was mid-dilated and minimally reacting to light OD. The lens was slightly opacity OU. A fundus examination revealed that discs were waxy pale with a CDR of 0.4 OD and 0.3 OS, respectively. Bony spicule pigmentation diffused in the mid-peripheral and peripheral retina (Fig. 2A). Macular OCT suggested no significant abnormality OU (Fig. 2B). However, a tubular visual field was observed in bilateral eyes (Fig. 2C). Decreased a- and b-wave amplitudes were observed in both eyes with ff-ERG (Fig. S2). Gonioscopy revealed closed angle in all quadrant OD, whereas narrow ACA in three quadrants OS. The ocular biometric parameters of both eyes were shown in Table 1. The IOP was out of control with four kinds of anti-glaucoma medications, thus combined cataract surgery and trabeculectomy were performed on the right eye. Whole-circumference unstable zonular fibers were discovered during phacoemulsification, treated by the implantation of a capsular tension ring. Simultaneously, the right eye underwent the IZHV to prevent malignant glaucoma. Laser peripheral iridotomy (LPI) was performed in the left eye (Fig. 2D). The postoperative BCVA was 20/32 OD, and IOP was maintained within normal at postoperative 2 years.

A 47-year-old male with established RP for 13 years was found high IOP bilaterally on the regular reviews. He had a history of high myopia. The BCVA was 20/125 OD and 20/32 OS. IOP with applanation was 27 mmHg OU. A slit-lamp examination showed the peripheral anterior chamber of both eyes was shallow with VH grade 2. The fundus examination revealed the retinal vessels were strongly attenuated, diffused chorioretinal atrophy OU and waxy pale discs with a CDR of 0.9 OD and 0.8 OS. We scarcely found bony spicules existed in the retina (Fig. 3A) and no detectable waves in ff-ERG (Fig. S2). Macular OCT revealed an attenuated outer nuclear layer, RPE, and loss of outer/inner segments (Fig. 3B). Significantly great impairment was observed with perimetry (Fig. 3C). Gonioscopy bilaterally indicated the four-quadrant angle was iridotrabecular appositonal and could be re-opend in dynamic gonioscope, so combined laser peripheral iridoplasty and LPI were performed in both eyes. The postoperative PAC widened (Fig. 3D) and IOP consistently was kept under control throughout a 2-year follow-up with the application of topical IOP-lowering eye drops.