The pathological association between the anterior eye segment and the retina in a murine model of neovascular glaucoma.

Neovascular glaucoma (NVG) is caused by the formation of new blood vessels in the angle, iris, and cornea in retinal ischemic disease, such as proliferative diabetic retinopathy (PDR) and retinal vein occlusion (RVO), which can reduce the visual acuity. However, the pathophysiological symptoms of NVG are still not well understood because there is no model for the formation of NVG in the angle, iris, and cornea. The aim of this study was to investigate the involvement of NVG during ischemic disease, in a murine model of retinal ischemia. We evaluated the changes of the intraocular pressure (IOP) and pathological symptoms in the anterior eye segment and retina in this model, and the changes in the RNA or protein expression of vascular endothelial growth factor (VEGF) and fibrosis-related factors were analyzed in the retina and cornea by quantitative real-time polymerase chain reaction or western blot, respectively. Furthermore, we examined the changes in IOP after intravitreal injection of an anti-VEGF antibody. First, NVG formed in the retinal ischemic murine model, and the IOP was elevated in mice with NVG formation. Interestingly, VEGF expression was decreased in the retina but increased in the cornea in the murine model of NVG. On the other hand, fibrosis-related factors were increased in the retina and also significantly increased in the cornea in NVG. Moreover, the administration of anti-VEGF antibody immediately after vessel occlusion suppressed the increase in IOP, but administration at 7 days after vessel occlusion accelerated the increase in IOP. These findings suggest that the formation of NVG may be correlated with the pathological symptoms of retinal ischemic disease, via changes in VEGF and fibrosis-related factor expression.

High speed, long range, deep penetration swept source OCT for structural and angiographic imaging of the anterior eye.

This study reports the development of prototype swept-source optical coherence tomography (SS-OCT) technology for imaging the anterior eye. Advances in vertical-cavity surface-emitting laser (VCSEL) light sources, signal processing, optics and mechanical designs, enable a unique combination of high speed, long range, and deep penetration that addresses the challenges of anterior eye imaging. We demonstrate SS-OCT with a 325 kHz A-scan rate, 12.2 µm axial resolution (in air), and 15.5 mm depth range (in air) at 1310 nm wavelength. The ultrahigh 325 kHz A-scan rate not only facilitates biometry measurements by minimizing acquisition time and thus reducing motion, but also enables volumetric OCT for comprehensive structural analysis and OCT angiography (OCTA) for visualizing vasculature. The 15.5 mm (~ 11.6 mm in tissue) depth range spans all optical surfaces from the anterior cornea to the posterior lens capsule. The 1310 nm wavelength range enables structural OCT and OCTA deep in the sclera and through the iris. Achieving high speed and long range requires linearizing the VCSEL wavenumber sweep to efficiently utilize analog-to-digital conversion bandwidth. Dual channel recording of the OCT and calibration interferometer fringe signals, as well as sweep to sweep wavenumber compensation, is used to achieve invariant 12.2 µm (~ 9.1 µm in tissue) axial resolution and optimum point spread function throughout the depth range. Dynamic focusing using a tunable liquid lens extends the effective depth of field while preserving the lateral resolution. Improved optical and mechanical design, including parallax "split view" iris cameras and stable, ergonomic patient interface, facilitates accurate instrument positioning, reduces patient motion, and leads to improved imaging data yield and measurement accuracy. We present structural and angiographic OCT images of the anterior eye, demonstrating the unique imaging capabilities using representative scanning protocols which may be relevant to future research and clinical applications.

Role of anterior segment optical coherence tomography angiography in the assessment of acute chemical ocular injury: a pilot animal model study.

To examine the use of anterior segment-optical coherence tomography angiography (AS-OCTA) in the assessment of limbal ischemia in an animal model chemical ocular injury. We conducted a prospective study using an established chemical ocular injury model in 6 rabbits (12 eyes), dividing the cornea limbus into 4 quadrants. Chemical injury grade was induced based on extent of limbal injury (0 to 360 degrees) and all eyes underwent serial slit-lamp with AS-OCTA imaging up to one month. Main outcome measure was changes in AS-OCTA vessel density (VD) comparing injured and control cornea limbal quadrants within 24 h and at one month. AS-OCTA was able to detect differences in limbal VD reduction comparing injured (3.3 ± 2.4%) and control quadrants (7.6 ± 2.3%; p < 0.001) within 24 h of ocular chemical injury. We also observed that AS-OCTA VD reduction was highly correlated with the number of quadrants injured (r = - 0.89; p < 0.001; 95% CI - 5.65 to - 1.87). Corneal vascularization was detected by AS-OCTA in injured compared to control quadrants (10.1 ± 4.3% vs 7.0 ± 1.2%; p = 0.025) at 1 month. Our animal pilot study suggests that AS-OCTA was able to detect limbal vessel disruption from various severities of acute chemical insult, and in the future, could potentially serve as an adjunct in providing objective grading of acute ocular chemical injury once validated in a clinical trial.

A Rare Case of Anterior Segment Ischemia Following Wright's Modification of the Hummelsheim Procedure for Total Lateral Rectus Muscle Palsy.

A 53-year-old woman presented with diplopia and deviation of the left eye for the past 3 years. She had non-resolving isolated left lateral rectus palsy. She underwent a medial rectus recession and Hummelsheim (Wright's modification) procedure in her left eye. Postoperatively, the anterior segment ischemia resolved with steroids. [J Pediatr Ophthalmol Strabismus. 2019;56:e53-e56.].

Transposition procedures in Duane retraction syndrome.

Duane retraction syndrome, or Duane syndrome (DS), is one of several congenital cranial dysinnervation disorders. Patients present with limited horizontal eye movement(s) and globe retraction with eyelid fissure narrowing on attempted adduction due to co-contraction of the lateral and medial rectus muscles in one or both eyes. Various surgical approaches have been proposed to improve binocular alignment, reduce head turn, and minimize undesirable up- or downshoots in DS. Transposition procedures are one such approach, and a number of techniques have been described. These may involve one or both vertical rectus muscles and may or may not include full or partial disinsertion of the rectus muscle(s) from the insertion. Options involving both vertical rectus muscles include full vertical rectus transposition (VRT), partial VRT, rectus muscle union, and other modifications to be discussed. Options involving one vertical rectus muscle include superior rectus transposition (SRT) and inferior rectus transposition (IRT). The effectiveness of any transposition procedure may be enhanced with augmentation (posterior fixation) sutures, resection of the transposed muscle(s), and/or simultaneous weakening of the ipsilateral medial rectus muscle. This review discusses the indications, strengths, weaknesses, and other considerations of these approaches within the context of DS. Since the majority of DS cases are unilateral and most have the esotropic form, this will be the main focus of the review, although other forms will also be discussed.

Association of Change in Iris Vessel Density in Optical Coherence Tomography Angiography With Anterior Segment Ischemia After Strabismus Surgery.

Importance: Anterior segment ischemia (ASI) is a rare but potentially serious complication of strabismus surgery. Indocyanine green angiography and fluorescein angiography have been used to reveal iris-filling defects for clinicians considering a patient's risk of ASI. However, both are limited by invasive and time-consuming nature and potential adverse effects. Recently, optic coherence tomography angiography (OCT-A) has been introduced and used to image iris vasculature in individuals without abnormalities. Objective: To determine the use of iris OCT-A for patients undergoing strabismus surgery and who are at risk for ASI. Design, Setting, and Participants: This prospective case series study took place in an academic center. Adults undergoing strabismus surgery on at least 1 vertical muscle were prospectively recruited. The study took place from June to November 2017, and analysis began in January 2018. Interventions: Indocyanine green angiography and OCT-A of the iris preoperatively and 1 day postoperatively. Main Outcomes and Measures: A masked examiner evaluated all images and determined whether any filling defects were present qualitatively (lack of perfusion) and quantitatively (for OCT-A using internal software to calculate vessel density). Results: Ten eyes of 9 individuals (mean [SD] age, 63 [11] years) were included. Two individuals (22.2%) identified as Hispanic, and 7 (77.8%) identified as white. There were 6 women (66.7%). The mean preoperative vessel density (percentage of the area occupied by vessels) averaged for all quadrants decreased from 57% preoperatively to 55% postoperatively (mean difference, 2%; 95% CI, 0.4%-4.2%; P = .05). When comparing quadrants adjacent to operated muscles, the mean vessel density decreased from 56% to 53% (mean difference, 2.6%; 95% CI, 0.17%-4.8%; P = .02). In addition, OCT-A detected vascular filling defects in the quadrant adjacent to the operated muscle on the patients in whom they were present (n = 1, inferior rectus recession). Conclusions and Relevance: In this preliminary study, OCT-A determined iris vessel filling defects when present. In addition, OCT-A gives qualitative vessel density values that can be compared preoperatively and postoperatively although the clinical relevance of small differences is not known. While only 10 eyes were evaluated, and as such generalizability of these findings cannot be determined, the results suggest that OCT-A may be a useful tool in the evaluation of patients undergoing strabismus surgery to determine whether a patient is at risk to develop ASI.

Risk of Anterior Segment Ischemia Following Simultaneous Three Rectus Muscle Surgery: Results from a Single Tertiary Care Centre.

PURPOSE: The aim of the study was to determine the risk of anterior segment ischemia (ASI) after simultaneous three rectus muscle surgery. METHODS: A retrospective cohort study was conducted. All patients who underwent simultaneous three rectus muscle surgery from January 2003 to December 2014 were included. Medical records were reviewed for signs of acute ASI in the postoperative period or presence of any late sequelae. Those patients who had pre-existing corneal pathology obscuring visualisation of anterior chamber and iris were excluded. RESULTS: A total of 87 patients (54 males and 33 females) were included in the analysis. The mean age at the time of surgery was 22.5 ± 12.9 years (range 3.5 to 69.5 years). The common indications for surgery were monocular elevation deficit, sensory strabismus and third and sixth cranial nerve palsies. Mild form of ASI was seen in two patients, with no systemic or local illness, aged 30 and 9 years respectively. Both the patients underwent surgery on two vertical rectus muscle and one horizontal rectus muscle via the fornix approach. ASI resolved with topical steroids within two weeks in both the patients. CONCLUSIONS: The risk of anterior segment ischemia after uncomplicated simultaneous three rectus muscle surgery was found to be 2.3% (95% CI = 0.3 to 8.1). It may occur in otherwise healthy young patients and even after fornix approach surgery.

Anterior segment ischemia: etiology, assessment, and management.

Anterior segment ischemia (ASI) is a potentially serious but rare complication of strabismus surgery. Among several risk factors, ASI occurs after strabismus surgery because of the nature of the anterior segment circulation. Disinsertion of rectus muscles leads to a decrease in the blood supply to the various anterior segment structures. We report a series of retrospective and prospective studies performed by our group focused on determining the risk of anterior segment ischemia following strabismus surgery, diagnosis, and modifications to surgical techniques to minimize the impact on anterior segment circulation. We found a significant decrease in postoperative anterior segment blood flow when operating vertical rectus muscles. Plication procedures preserve anterior segment circulation, and modifications to the technique allow the performance of adjustable sutures. Small adjustable selective procedures that spare the ciliary vessels have been demonstrated to be effective in patients with vertical and torsional diplopia. Ciliary sparing augmented adjustable transposition surgery decreases the risk of anterior segment ischemia while allowing management of potential post-operative alignment complications. Finally, ocular coherence tomography angiography is a valuable quantitative and qualitative technique to evaluate anterior segment ischemia. Strabismus surgeons should be aware of the risks of anterior segment ischemia when operating vertical rectus muscles. Modifications to standard surgical techniques allow surgeons to perform complex strabismus surgery in patients at risk for anterior segment ischemia.

Incidence of anterior segment neovascularization during intravitreal treatment for macular edema secondary to central retinal vein occlusion.

PURPOSE:: To analyze the effects of injections of intravitreal triamcinolone acetonide (IVTA) and intravitreal bevacizumab (IVB) on the incidence rates of anterior segment neovascularization (ASN) and neovascular glaucoma (NVG) in patients with macular edema secondary to central retinal vein occlusion (CRVO). METHODS:: In this prospective, randomized, double-masked, sham-controlled study, 35 patients with macular edema following CRVO were randomized to intravitreal bevacizumab, intravitreal triamcinolone acetonide, or sham injections during the first 6 months of the study. The primary outcome was the incidence rate of ASN at month 6. The secondary outcomes were the mean changes from baseline in best-corrected visual acuity (BCVA) and central foveal thickness (CFT) on optical coherence tomography over time to month 12. RESULTS:: ASN developed in 8 (22.86%) eyes, including 5 (62.50%) eyes in the sham group and 3 (37.50%) eyes in the IVTA group, during 12 months of fol low-up (p=0.009). BCVA differed significantly (p<0.05) among the groups only at month 1. CFT did not differ significantly (p<0.05) among the groups over 12 months. NVG required surgery and developed in one eye despite laser treatment. CONCLUSION:: Early treatment with intravitreal antivascular endothelial growth factor therapy decreases the rates of ASN and NVG after CRVO.

Incidence of anterior segment neovascularization during intravitreal treatment for macular edema secondary to central retinal vein occlusion / Incidência de neovasos de segmento anterior durante o tratamento de edema macular secundário a oclusão da veia central da retina

ABSTRACT Purpose: To analyze the effects of injections of intravitreal triamcinolone acetonide (IVTA) and intravitreal bevacizumab (IVB) on the incidence rates of anterior segment neovascularization (ASN) and neovascular glaucoma (NVG) in patients with macular edema secondary to central retinal vein occlusion (CRVO). Methods: In this prospective, randomized, double-masked, sham-controlled study, 35 patients with macular edema following CRVO were randomized to intravitreal bevacizumab, intravitreal triamcinolone acetonide, or sham injections during the first 6 months of the study. The primary outcome was the incidence rate of ASN at month 6. The secondary outcomes were the mean changes from baseline in best-corrected visual acuity (BCVA) and central foveal thickness (CFT) on optical coherence tomography over time to month 12. Results: ASN developed in 8 (22.86%) eyes, including 5 (62.50%) eyes in the sham group and 3 (37.50%) eyes in the IVTA group, during 12 months of fol low-up (p=0.009). BCVA differed significantly (p<0.05) among the groups only at month 1. CFT did not differ significantly (p<0.05) among the groups over 12 months. NVG required surgery and developed in one eye despite laser treatment. Conclusion: Early treatment with intravitreal antivascular endothelial growth factor therapy decreases the rates of ASN and NVG after CRVO.

RESUMO Objetivo: Analisar as taxas de incidência de neovascularização do segmento anterior (NSA) e de glaucoma neovascular (GNV), em pacientes com edema macular secundário a oclusão de veia central da retina (OVCR), em tratamento com injeções intravítreas de triamcinolona (IVTA) ou bevacizumab (IVB). Métodos: Neste estudo prospectivo, randomizado, duplo mascarado e sham controlado, 35 pacientes com edema macular secundário a OVCR foram randomizados para IVB, IVTA ou para o grupo controle (sham), durante os 6 primeiros meses do estudo. O desfecho primário foi a taxa de incidência de NSA no mês 6. Os desfechos secundários foram alterações médias da acuidade visual corrigida (BCVA) e espessura foveal central (EFC) ao exame de tomografia de coerência óptica, até o mês 12. Resultados: NSA ocorreu em oito (22,86%) olhos, cinco (62,50%) olhos no grupo sham e três (37,50%) olhos no grupo tratado com injeções intravítreas de Triamcinolona, Não houve nenhum caso com NSA no grupo tratado com bevacizumab durante 12 meses de acompanhamento (p=0,009). A BCVA apresentou diferença estatisticamente significante (p<0,05) entre os grupos, somente no mês 1. A EFC não apresentou diferenças estatisticamente significantes (p<0,05) entre os grupos ao longo dos 12 meses. GNV ocorreu em um olho apesar do tratamento com laser e este paciente necessitou de intervenção cirúrgica. Conclusão: O tratamento precoce com injeções intravítreas de Anti VEGF podem diminuir as taxas de neovascularização do segmento anterior e glaucoma neovascular após oclusão de veia central da retina.

Complicaciones de la transposición aumentada de recto superior en el síndrome de Duane / Complications of augmented superior rectus transposition in Duane syndrome

CASO CLÍNICO: Paciente con síndrome de Duane, operado con transposición aumentada de recto superior (TRS) al recto lateral (RL), y recesión del recto medio (RM). En el postoperatorio se observó desviación vertical, torsional y diplopía. La retirada de la fijación escleral y la recesión del RS lo resolvieron. DISCUSIÓN: La TRS al RL está descrita en el tratamiento del síndrome de Duane con resultados controvertidos. Puede ser una alternativa a la transposición de los rectos verticales cuando asocia la recesión del RM en el mismo procedimiento, o en el postoperatorio inmediato para disminuir el riesgo de isquemia del segmento anterior

CLINICAL CASE: A patient diagnosed with Duane syndrome underwent an augmented superior rectus transposition (SRT) to lateral rectus (LR) and medial rectus (MR) recession. Vertical, torsional deviation and diplopia were observed post-operatively. Removal of the Foster suture and superior rectus recession resolved the symptoms. DISCUSSION: SRT to LR is proposed in Duane syndrome with a favorable outcome. The benefit of SRT is open to debate. It could be an alternative for the vertical rectus transposition when MR recession has to be operated on in the same procedure, or in the immediate post-operative period, in order to decrease the risk of anterior segment ischaemia

Factors Associated with Worsening Proliferative Diabetic Retinopathy in Eyes Treated with Panretinal Photocoagulation or Ranibizumab.

PURPOSE: To compare rates and identify predictive factors for events that represent worsening of proliferative diabetic retinopathy (PDR) in eyes treated with panretinal photocoagulation (PRP) or ranibizumab. DESIGN: Randomized clinical trial (55 United States sites). PARTICIPANTS: Three hundred ninety-four study eyes from 305 adults with PDR, visual acuity (VA) 20/320 or better, and no history of PRP. INTERVENTION: Panretinal photocoagulation or intravitreous ranibizumab injections (0.5 mg/0.05 ml). MAIN OUTCOME MEASURES: Time from randomization to a composite PDR-worsening outcome defined as the first occurrence of vitreous hemorrhage, retinal detachment, anterior segment neovascularization, or neovascular glaucoma. RESULTS: Through 2 years, the cumulative probability of worsening PDR was 42% (PRP) versus 34% (ranibizumab; hazard ratio [HR], 1.33; 99% confidence interval [CI], 0.90 to 1.98; P = 0.063). Worse baseline levels of diabetic retinopathy severity (Early Treatment Diabetic Retinopathy Study scale) were associated with increased risk of worsening PDR, regardless of treatment group (64% [high-risk PDR or worse] vs. 23% [moderate PDR or better]; HR, 3.97; 99% CI, 2.48 to 6.36; P < 0.001). In the PRP group, eyes receiving pattern scan versus conventional single-spot PRP also were at higher risk for worsening PDR (60% vs. 39%; HR, 2.04; 99% CI, 1.02 to 4.08; P = 0.008), regardless of the number of spots placed or the number of sittings to complete the initial PRP. Eyes in both groups with vision-impairing (VA 20/32 or worse) center-involved diabetic macular edema (DME) at baseline were required to receive ranibizumab for center-involved DME. Therefore the composite outcome was compared by treatment in the subgroup of eyes that did not have vision-impairing center-involved DME at baseline. For these eyes, the rate of PDR-worsening was greater with PRP than ranibizumab (45% vs. 31%; HR, 1.62; 99% CI, 1.01 to 2.60; P = 0.008). CONCLUSIONS: In eyes with PDR, ranibizumab resulted in less PDR worsening compared with PRP, especially in eyes not required to receive ranibizumab for center-involved DME. Although anti-vascular endothelial growth factor therapy requires a more frequent visit schedule than PRP, these findings provide additional evidence supporting the use of ranibizumab as an alternative therapy to PRP for PDR, at least through 2 years.

CONCURRENT ENDOPHTHALMITIS AND ANTERIOR SEGMENT ISCHEMIA AFTER STRABISMUS SURGERY.

BACKGROUND/PURPOSE: To report a case of simultaneous endophthalmitis and anterior segment ischemia (ASI) that occurred in a patient after strabismus surgery. This is the first known case of both complications occurring at the same time. METHODS: Case report. RESULTS: A 60-year-old woman presented with eye pain and loss of vision 6 days after uncomplicated strabismus surgery for thyroid eye disease. On examination, she had corneal edema, anterior segment fibrin, an atonic iris, and no view to the posterior segment. On fluorescein angiography of the anterior segment, a large portion of the iris was nonperfused. Posterior segment ultrasound showed dense vitritis and a choroidal abscess. Intraoperative cultures grew methicillin-resistant Staphylococcus aureus. CONCLUSIONS: Endophthalmitis and anterior segment ischemia are both exceedingly rare complications of strabismus surgery. It is possible that each one occurred independently, but more likely one process potentiated the other. One possible mechanism is inflammation-induced thrombosis.

Treatment of Recalcitrant Cyclitic Neovascular Pupillary Membranes.

PURPOSE: To describe a new approach for the treatment of cyclitic vascularized pupillary membranes. PATIENTS AND METHODS: A retrospective interventional case series describing 3 patients undergoing a novel interventional treatment at a single institutional center. RESULTS: This technique allows successful completion of laser membranectomy to create a pupillary aperture. This aperture resulted in improved vision and an enhanced ability to examine for and treat ischemic retinal disease. CONCLUSIONS: This technique describes a new use for bevacizumab that enables the surgeon to treat recalcitrant and recurrent cyclitic vascularized pupillary membranes.

Optical coherence tomography angiography in dural carotid-cavernous sinus fistula.

BACKGROUND: Recently, applications of optical coherence tomography angiography (OCTA) have been limited to the retina and posterior segment. Although early studies have described its use for other clinical applications, its role in anterior segment vasculature and optic disc imaging has been limited thus far. CASE PRESENTATION: We describe a novel clinical application of OCTA in a patient with dural carotid-cavernous sinus fistula (CCF), which was complicated by increased intra-ocular pressure (IOP). In this case report, we used the OCTA to delineate increased epsicleral venous flow in the affected eye with secondary raised IOP. Current measurements of episcleral venous pressure are either invasive or provide highly variable results, thus the OCTA may have the potential to provide a more reliable approach to assess episcleral vasculature. We also describe the use of OCTA to detect early glaucomatous nerve damage, associated with focal reductions in peripapillary retinal perfusion. CONCLUSIONS: We present an early report of using OCTA of the anterior segment to allow rapid, non-invasive delineation of abnormal episcleral venous plexus secondary to dural CCF. The OCTA was also useful for detecting early reduction in peripapillary retinal perfusion, which suggests early glaucomatous optic neuropathy. This suggests that OCTA may have a role for determining risk of glaucoma in patients with CCF in future.

Wholemount imaging reveals abnormalities of the aqueous outflow pathway and corneal vascularity in Foxc1 and Bmp4 heterozygous mice.

Mutations in the FOXC1/Foxc1 gene in humans and mice and Bmp4 in mice are associated with congenital anterior segment dysgenesis (ASD) and the development of the aqueous outflow structures throughout the limbus. The aim of this study was to advance our understanding of anterior segment abnormalities in mouse models of ASD using a 3-D imaging approach. Holistic imaging information combined with quantitative measurements were carried out on PECAM-1 stained individual components of the aqueous outflow vessels and corneal vasculature of Foxc1(+/-) on the C57BL/6Jx129 and ICR backgrounds, Bmp4(+/-) ICR mice, and wildtype mice from each background. In both wildtype and heterozygotes, singular, bifurcated and plexus forms of Schlemm's canal were noted. Of note, missing portions of the canal were seen in the heterozygous groups but not in wildtype animals. In general, we found the number of collector channels to be reduced in both heterozygotes. Lastly, we found a significant increase in the complexity of the corneal arcades and their penetration into the cornea in heterozygotes as compared with wild types. In conclusion, our 3-D imaging studies have revealed a more complex arrangement of both the aqueous vessels and corneal arcades in Foxc1(+/-) and Bmp4(+/-) heterozygotes, and further advance our understanding of how such abnormalities could impact on IOP and the aetiology of glaucoma.

Anterior Segment Ischemia in Viper Bite.

PURPOSE: To describe the clinical and histopathological features of post viper bite anterior segment ischemia. METHODS: Seven patients with ocular complications following viper bite referred to uveitis clinic had slit-lamp examination, intraocular pressure (IOP) measurement, and fundus evaluation. Iris and fundus fluorescein angiography was performed on 2 patients. Histopathological examination was performed on iris tissues collected during cataract surgery. RESULTS: Strikingly similar clinical findings were noted, including circumpupillary superficial iris atrophy, mid dilated fixed pupil, marked pigment dispersion, low IOP, and cataract. All clinical signs were noted only in the anterior segment; the posterior segment was normal. Histopathology of iris revealed atrophy of iris stroma, necrotic iris pigment epithelium, and infiltration of T lymphocytes and fibrous membrane. Poor visual outcome was noted in patients with low IOP. CONCLUSION: Viper bite victims presented with clinical and histopathological signs of anterior segment ischemia and secondary inflammatory signs mimicking uveitis.