High-intensity Focused Ultrasound Treatment in Moderate Glaucoma Patients: Results of a 2-Year Prospective Clinical Trial.

PRECIS: Ultrasound Cyclo Plasty (UCP) treatment using high-intensity focused ultrasound (HIFU) is an effective and safe therapy to reduce intraocular pressure (IOP) in moderate glaucoma patients as was measured during a 2-year follow-up period. PURPOSE: The purpose of this study was to evaluate the long-term safety and efficacy of the UCP procedure using HIFU in moderate glaucoma patients. PATIENTS AND METHODS: A prospective interventional noncomparative study was carried out. Fifteen patients (15 eyes) with moderate open-angle glaucoma were enrolled. All eyes were treated with UCP-HIFU. A thorough ophthalmic examination and IOP measurements were performed before the UCP-HIFU procedure and at 1 day, 1 week, 4 weeks, 3 months, 6 months, 1 year, and 2 years after the procedure. The primary outcome was defined as a surgical success (IOP reduction of 20% or ≥5 mm Hg) at the last follow-up visit. The secondary outcomes were the mean IOP at each follow-up visit, number of medications used, complications profile, and reinterventions. RESULTS: The mean preoperative IOP at baseline was 26.8±5.0 mm Hg. All patients had a positive response and a lower IOP after treatment, with a relatively stable 31% reduction in IOP during the follow-up period. A significant reduction in IOP was observed at all postprocedure examination points (P<0.01), with a mean 17.6±4.4 mm Hg at 2 years after the procedure (P=0.005). Surgical success was achieved in 87% of the patients at their last follow-up visit. There was a nonsignificant decrease in the mean number of glaucoma medications from 2.5±0.8 to 2.0±1.0 at 2 years (P=0.48). No major intraoperative or postoperative complications were noted. CONCLUSION: UCP-HIFU treatment is an effective, safe, and well-tolerated method to reduce IOP in patients with moderate glaucoma.

Effect of light and diurnal variation on macular thickness in X-linked retinoschisis: a case series.

BACKGROUND: Diurnal variations in foveal thickness have been reported in several ocular pathologies including X-linked retinoschisis (XLRS), but its underlying mechanism is poorly understood. Rods are active under scotopic conditions with high metabolic demand, and its decrease may have positive effect on metabolic activity and macular thickness. The purpose of this study is to evaluate whether exposure to light and diurnal variation influence macular thickness in XLRS patients. METHODS: Five patients with clinical suspicion of XLRS underwent RS1 gene sequencing and optical coherence tomography measurements at three consecutive times: morning following sleep in a dark room, morning following sleep in an illuminated room, and late afternoon following sleep in an illuminated room. Central macular thickness (CMT) was compared between measurements, and molecular analysis was performed. RESULTS: Five RS1 mutations were identified: p.Gly140Arg, p.Arg141Cys, p.Gly109Glu, p.Pro193Leu, and p.Arg200His in patients 1-5, respectively. Two patients (4-5) had atrophied macula and were excluded from macular thickness variation analysis. A significant decrease in CMT between morning and afternoon measurements was observed in all patients (1-3: mean: 455.0 ± 32 µm to 342.17 ± 39 µm, 25%). Morning measurements following sleep in an illuminated room show a CMT reduction in all eyes of all patients with a mean reduction of 113 µm (mean: 547.17 ± 105 µm to 455.0 ± 32 µm, 17%). CONCLUSIONS: Among XLRS patients, CMT decreased at the afternoon compared to the morning of the same day and may be reduced following sleep in an illuminated room. These results help shed light on the pathophysiologic process underlying intraretinal fluid accumulation involved with the disease.

Anterior-Segment Optical Coherence Tomography-Guided Measurement Of A Melting Ulcer For Follow-Up Of Corneoscleral Thinning Progression.

PURPOSE: To evaluate the feasibility of using anterior-segment optical coherence tomography (AS-OCT) for three-dimensional assessment of corneoscleral thinning progression in ulcers after pterygium removal. METHODS: A patient with corneoscleral melting after pterygium removal surgery and mitomycin C treatment was evaluated using AS-OCT imaging of the corneoscleral ulcer at five consecutive time points, up to 2 years. AS-OCT scans of 8.3×5.6 mm (15°×10°) containing 41 B-scans spaced 139 µm apart were performed monthly for 4 months and then at 2 years following pterygium removal. A single B-scan was comprised of 768 A-scans. Ten B-scans of the same position were averaged in a single AS-OCT image. The area of ulcer's section (AUS) was measured in seven fixed landmarks through a horizontally aligned plane in order to provide an estimation of the three-dimensional size of the lesion. RESULTS: The AUS in the two superior locations increased during the follow-up period to an average of 114% at 2 years compared to the initial visit. In the other five locations (three midline and two inferior), the AUS decreased and was on average 64% in the midline and 29% in the inferior locations at 24 months. CONCLUSION: AS-OCT provided a readily available assessment of the lesion's three-dimensional size during repeated follow-ups and identification of localized areas at higher risk for perforation. This method may potentially be useful for corneal surface pathologies requiring repeated follow-ups and may aid in decision-making regarding corneal thickness based on an accurate measurement.

Microarchitecture of Schlemm Canal Before and After Cataract Extraction Surgery.

PRECIS: Schlemm canal (SC) expands after cataract extraction (CE), both in the area and in volume by 25% as was measured using enhanced-depth imaging optical coherent tomography (EDI-OCT) in patients before and 1 week after CE. PURPOSE: This study aims to characterize the structural and volume changes on the microstructure of SC in patients before and after uneventful phacoemulsification CE by using EDI-OCT. MATERIALS AND METHODS: Forty-one serial horizontal EDI-OCT B-scans (interval between B-scans, 69 µm) were obtained in the nasal corneoscleral limbus before and 1 week after CE. The structure of aqueous channels, conjunctival blood vessels and iris anatomy in each scan were used as landmarks to select for overlapping scans taken before and following CE. The SC cross-section area was measured in each of the selected scans and SC volume was determined following a 3-dimensional reconstruction. RESULTS: Eleven eyes (6 females and 5 males) were imaged successfully before and after CE. Mean age was 70.54±11.38 years. The mean axial length was 23.10±0.87 mm. After CE, the mean best-corrected visual acuity in logMAR improved from 0.4±0.13 to 0.2±0.13 (P=0.028). There was no significant change in the mean intraocular pressure before and after CE (15.09±1.33 to 15.0±2.16 mm Hg; P=0.39). The mean SC cross-section area increased by 25%, from 4744±376 to 5941±1048 µm (P<0.001). SC volume in the analyzed region increased by 25% from 6,641,473±585,954 to 8,317,909±1,328,809 µm (P<0.001). CONCLUSION: CE expands SC dimensions in healthy eyes. EDI-OCT imaging of SC may prove useful in the evaluation of the SC dimensions in vivo before and after CE.

Macular Corneal Dystrophy and Posterior Corneal Abnormalities.

PURPOSE: This study reports the presentation of 2 families with macular corneal dystrophy (MCD). The aim of this study was to show whether ultrasound biomicroscopy (UBM) can, based on posterior changes of the cornea in MCD, assist in the choice of surgery, either anterior lamellar keratoplasty (DALK) or penetrating keratoplasty (PK), compared with optical coherence tomography (OCT) and Scheimpflug. METHODS: Six patients with MCD were examined for their best-corrected visual acuity, slit-lamp, OCT, UBM, and Scheimpflug findings. Blood samples for DNA and exons of the CHST6 gene were screened for mutations. RESULTS: All 6 patients showed typical MCD signs at the slit lamp. Corneal transplantation was required in 2 patients in both eyes. Recurrence of MCD was observed in 2 eyes after the DALK procedure (patient A5, age 48 years, right eye and B1, 51 years, left eye), whereas the 2 eyes after PK (patient A5, age 48 years, left eye and patient B1, 51 years, right eye) remained clear (for 10 years of follow-up in patient A5 and 4 years in patient B1). In 2 patients (A1 and A3), corneal thinning could be evaluated by OCT. In 3 patients (A2, 3, and 4), UBM disclosed deeper pathologies including opacities, loss of continuity, and focal protrusions of the posterior cornea, which were not evident by other devices. In family A, a novel mutation was identified. CONCLUSIONS: Our UBM examination of MCD shows alterations of the cornea's posterior layer and confirms the known clinical and histological findings of MCD that PK represents the therapy of choice, contrary to DALK. The novel CHST6 mutation shows the heterogeneity of MCD.