Usage of E-Polytetrafluoroethylene (e-PTFE) Membrane for Managing Trabeculectomy Flap- Related Over-Filtration Due to Unavailability of Scleral Patch Graft during Nation-Wide Lockdown

Scleral flap tears during trabeculectomy are difficult to repair in a predictable fashion. Donor scleral flap reinforcements are commonly preferred for managing trabeculectomy flap-related over-filtration, leading to shallow anterior chamber (AC). Due to the advent of COVID-19 lockdown, especially in the initial phases, eye banking activities almost came to a standstill, with almost no corneal and/or scleral tissue retrievals. Hence, in this manuscript we have presented a mini case series with follow-up of two of our cases; where Gore-Tex (e-polytetrafluoroethylene) implant was used as an alternative to scleral patch graft, for managing trabeculectomy flap-related over-filtration, with their pros and cons. Though Gore-Tex implant stability in both cases were contentious, it still served the purpose of managing the flap-related over- filtration and subsequent shallow AC.

Clinical management of a rare Peters’ anomaly-induced secondary childhood glaucoma: A case report

Childhood glaucoma is a rare disorder that occurs from birth until teenage years caused by an abnormality of aqueous humor pathways. About 50–70% of Peters' anomaly is accompanied by secondary childhood glaucoma. The presence of glaucoma will affect the prognosis. We reported the evaluation and treatment of secondary childhood glaucoma due to Peters’ anomaly. A 5 months-old boy was presented with the complaint of a enlarged left eye since 3 months old. The complaint was accompanied by a watering eye and frequently closed upon light exposure. The left eye looked opaquer than contralateral. Examination under anesthesia showed that the intraocular pressure (IOP) was 35 mmHg in the left eye and the corneal diameter was 14 mm. Other findings were keratopathy, diffuse corneal edema, buphthalmos, shallow anterior chamber, anterior synechiae, and linear slit shaped pupils in the nasal region. Patient was treated with ophthalmic timolol maleate which was later followed by trabeculectomy. After 1 week post-surgery, IOP assessment by palpation suggested the right eye within normal range while the IOP of left eye was higger than normal. Blepharospasm, epiphora, photophobia, bleb on superior, subconjunctiva bleeding, buphthalmos, keratopathy, minimal corneal edema, anterior chamber with shallow image, and posterior synechia were found in left eye anterior segment. In conclusion, trabeculotomy and trabeculectomy are recommended if there is no reduction of IOP observed after receiving timolol maleate therapy. The choice of surgical management is dependent on the feasibility of the protocol.

Aqueous misdirection syndrome masking as myopic surprise following phacoemulsification surgery

Aqueous misdirection syndrome is a rare but serious condition that can present after routine phacoemulsification surgery. This report examines a case of myopic surprise following an uncomplicated left eye (LE) phacoemulsification surgery. The patient had previous bilateral peripheral iridotomies for narrow anterior chamber angles. Repeat biometry measurement of the pseudophakic LE did not show shallow anterior chamber, and intraocular pressure (IOP) was normal at initial presentation. However, approximately 3 years postoperatively, LE IOP was raised. Surgical management was considered as medical and laser procedures did not stop deterioration. Clinical presentation of aqueous misdirection syndrome may be subtle and can occur weeks to years after routine uncomplicated phacoemulsification surgery. Myopic surprise may be the only initial presenting sign. Patients who are at risk of aqueous misdirection syndrome should be followed up closely after cataract surgery with accurate gonioscopic assessments for early diagnosis and treatment to prevent optic nerve damage.

Assessment of anterior chamber angle changes after phacoemulsification with swept-source OCT

AIM: To assess the changes of anterior chamber angle in patients with shallow anterior chamber after phacoemulsification combined with intraocular lens (IOL) implantation, based on anterior segment swept-source optical coherence tomography (AS-SS-OCT) measurements. METHODS: This was a prospective case control study; sixty eyes of sixty case were scheduled for cataract surgery with normal intraocular pressure (IOP). Based on anterior chamber depth (ACD) and gonioscopy findings, the eyes were divided into two groups: group of shallow anterior chamber and narrow angle (SAC group, 30 eyes); and group of normal anterior chamber group with wide angle (NAC group, 30 eyes). Measurements of ACD, anterior chamber volume (ACV), iris volume (IV), lens vault (LV), angle opening distance (AOD), angle recess area (ARA), trabecular iris space area (TISA), and trabecular iris angle (TIA) were conducted in each group before and 3mo after surgery. RESULTS: There was no significant difference in age, axial length (AL), corneal curvature, corneal diameter, intraocular pressure, and IV between two groups before surgery, except for the LV (P=0.000). ACD and ACV were prominently larger in the NAC group than the SAC group 3mo after operation (3.69±0.38 vs 3.85±0.39 mm, P=0.025; 161.37±19.47 vs 178.26±20.30 mm3, P=0.002). AOD750, ARA750 in nasal and inferior quadrants, TISA750 in all quadrants except temporal, and TIA750 in all quadrants in SAC group were significantly smaller than those in NAC group after operation (all P<0.05). CONCLUSION: Cataract surgery can deepen anterior chamber and increase the width of anterior chamber angle in Chinese subjects, but the angle related parameters including AOD750, ARA750, TISA750, TIA, TISA750, and ACV in patients with shallow anterior chamber and narrow angle do not reach the normal level.

Detection of shallow anterior chamber depth from two-dimensional anterior segment photographs using deep learning

Background The purpose of this study was to implement and evaluate a deep learning (DL) approach for automatically detecting shallow anterior chamber depth (ACD) from two-dimensional (2D) overview anterior segment photographs. Methods We trained a DL model using a dataset of anterior segment photographs collected from Shanghai Aier Eye Hospital from June 2018 to December 2019. A Pentacam HR system was used to capture a 2D overview eye image and measure the ACD. Shallow ACD was defined as ACD less than 2.4 mm. The DL model was evaluated by a five-fold cross-validation test in a hold-out testing dataset. We also evaluated the DL model by testing it against two glaucoma specialists. The performance of the DL model was calculated by metrics, including accuracy, sensitivity, specificity, and area under the receiver operating characteristic curve (AUC). Results A total of 3753 photographs (1720 shallow AC and 2033 deep AC images) were assigned to the training dataset, and 1302 photographs (509 shallow AC and 793 deep AC images) were held out for two internal testing datasets. In detecting shallow ACD in the internal hold-out testing dataset, the DL model achieved an AUC of 0.86 (95% CI, 0.83–0.90) with 80% sensitivity and 79% specificity. In the same testing dataset, the DL model also achieved better performance than the two glaucoma specialists (accuracy of 80% vs. accuracy of 74 and 69%). Conclusions We proposed a high-performing DL model to automatically detect shallow ACD from overview anterior segment photographs. Our DL model has potential applications in detecting and monitoring shallow ACD in the real world. Trial registration http://clinicaltrials.gov, NCT04340635, retrospectively registered on 29 March 2020.

What to Choose for Trabeculectomy, 10/0 Nylon Monofilament or 8/0 Virgin Silk?

Purpose: To compare between 10/0 nylon monofilament and 8/0 virgin silk for conventional trabeculectomy in terms of rate of complications and bleb morphology. Study Design: Quasi experimental study. Place and Duration of Study: Abbasi Shaheed Hospital, Karachi, from January 2017 to December 2018. Methods: Thirty six patients who underwent conventional trabeculectomy with 6 months follow-up were included. Trabeculectomy for congenital, neovascular, traumatic glaucoma, revised surgery and laser trabeculoplasty were excluded. In group A, scleral flap and conjunctiva were closed with 8/0 virgin silk and in group B, 10/0 nylon monofilament was used. Main outcome measure was complications. Results: Group A had 13 (36%) and group B had 23 (63.9%) patients. Mean age was 55.5 ± 10.69. Pre-operative Intraocular pressure (IOP) was 33.4 ± 6.3 and 33.5 ± 12 mm Hg in group A & B respectively. Postoperatively at 3rd month IOP was 16.8 in group A and 15.0 in group B (p = 0.24).Shallow Anterior chamber was in 53% (n = 7) patients with 8/0 silk and 13% (n = 3) patients with 10/0 nylon with p value of < 0.05. Seidel test was positive in 38% (n = 5) patients in group A (p < 0.01). Re-suturing was done in 38% (n = 5) patients in group A with a p-value (p < 0.01). Conclusion: Shallow anterior chamber, wound leak with positive seidel test and additional intervention for re-suturing were more common in group A than group B. Diffuse blebs were frequently seen with both suture materials. Suture material does not affect final intra ocular pressure and success of trabeculectomy. Key Words: Bleb, Trabeculectomy, 10/0 Nylon, 8/0 silk.

Vitreous Decompression Combined with Phacoemulsification for Medically Unresponsive Acute Angle Closure

The management of acute angle closure combined with an extremely shallow anterior chamber and cataract remains complex. This study evaluated a technique of vitreous needle aspiration combined with phacoemulsification for the treatment of acute angle closure with continuous high intraocular pressure (IOP). We retrospectively reviewed the results of vitreous needle aspiration combined with phacoemulsification in 17 eyes (17 patients) with acute angle closure with continuous high IOP and coexisting visually significant cataracts between September 2018 and April 2020 at the glaucoma unit of the affiliated Changshu Hospital of Xuzhou Medical University. The main outcomes were the best corrected visual acuity (BCVA), IOP, anterior chamber depth (ACD), angle open distance 500 (AOD500), number of antiglaucoma medications, and surgery-associated complications. There were no complications during phacoemulsification and a foldable acrylic intraocular lens was implanted in the capsular bag in all 17 patients. For all patients, vitreous needle aspiration was successful at the first attempt. The BCVA improved from 2.02 ± 0.54 logMAR preoperatively to 0.73 ± 0.57 logMAR postoperatively at the final examination ( p < 0.001 ). The mean IOP was 54.47 ± 5.33 mmHg preoperatively and 15.59 ± 2.35 mmHg at the final examination ( p < 0.001 ) without any medication. The ACD was 1.70 ± 0.16 mm preoperatively and 3.35 ± 1.51 mm at the final examination ( p < 0.001 ). The AOD500 was 0.07 ± 0.02 mm preoperatively and 0.51 ± 0.04 mm at the final examination ( p < 0.001 ). Our vitreous needle aspiration technique can be performed safely in phacoemulsification for the management of acute angle closure with continuous high IOP.

Nanophthalmos: An Update on the Biological Parameters and Fundus Abnormalities

Nanophthalmos is a clinical phenotype of simple microphthalmos, in which the anterior and posterior segments of the eyeball do not develop into a normal size without other major ocular or systemic anomalies. Typical clinical manifestations of nanophthalmos include short axial length, thickened sclera, small cornea, shallow anterior chamber, and increased lens-to-eye volume ratio. Currently, there is a lack of recognized diagnostic criteria for nanophthalmos. With the development of eye examination technologies, such as biological measurement and imaging examination, visualization and quantification of the eyeball’s shape and structure in nanophthalmos can be realized. New clinical features have been reported, which are of great significance for diagnosing and treating nanophthalmos. This review introduces the related concepts of nanophthalmos and the new developments in its clinical characterization.