Roberto Tosi

Ultrasound biomicroscopic and conventional ultrasonographic study of ocular dimensions in primary angle-closure glaucoma

OBJECTIVE To determine the biometric findings of ocular structures in primary angle-closure glaucoma (PACG). DESIGN An observational case series with comparisons among three groups (patients with acute/intermittent PACG [A/I-PACG], patients with chronic PACG [C-PACG], and normal subjects [N]). PARTICIPANTS A total of 54 white patients with PACG (13 male, 41 female) were studied: 10 with acute, 22 with intermittent, and 22 with chronic types of PACG. Forty-two normal white subjects (11 male, 31 female) were studied as control subjects. Only one eye was considered in each patient or subject. TESTING Ultrasound biomicroscopy (UBM) and standardized A-scan ultrasonography (immersion technique) were performed in each patient during the same session or within 1 to 3 days. MAIN OUTCOME MEASURES The following A-scan parameters were measured: anterior chamber depth (ACD), lens thickness (LT), axial length (AL), lens/axial length factor (LAF), and relative lens position (RLP). Ten UBM parameters were measured, the most important of which were anterior chamber angle, trabecular-ciliary process distance (TCPD), angle opening distance at 500 microm from the scleral spur (AOD 500), and scleral-ciliary process angle (SCPA). RESULTS Compared to normal subjects, the patients with PACG presented a shorter AL (A/I-PACG = 22.31 +/- 0.83 mm, C-PACG = 22.27 +/- 0.94 mm, N = 23.38 +/- 1.23 mm), a shallower ACD (A/I-PACG = 2.41 +/- 0.25 mm, C-PACG = 2.77 +/- 0.31 mm, N = 3.33 +/- 0.31 mm), a thicker lens (A/I-PACG = 5.10 +/- 0.33 mm, C-PACG = 4.92 +/- 0.27 mm, N = 4.60 +/- 0.53 mm), and a more anteriorly located lens (RLP values, A/I-PACG = 2.22 +/- 0.12, C-PACG = 2.34 +/- 0.16, N = 2.41 +/- 0.15). The LAF values in A/I-PACG, C-PACG, and N were 2.28 +/- 012, 2.20 +/- 0.11, and 1.97 +/- 0.12, respectively. Anterior chamber angle (A/I-PACG = 11.72 +/- 8.84, C-PACG = 19.87 +/- 9.83, N = 31.29 +/- 9.18 degrees) and SCPA (A/I-PACG = 28.71 +/- 4.02, C-PACG = 30.87 +/- 6.04, N = 53.13 +/- 9.58 degrees) were narrower, TCPD (A/I-PACG = 0.61 +/- 0.12 mm, C-PACG = 0.71 +/- 0.14 mm, N = 1.08 +/- 0.22 mm) and AOD 500 shorter (A/I-PACG = 0.13 +/- 0.09 mm, C-PACG = 0.21 +/- 0.10 mm, N = 0.36 +/- 0.11 mm) in patients with PACG. All the biometric differences proved statistically significant using the one-way analysis-of-variance test. CONCLUSIONS In patients with PACG, the anterior segment is more crowded because of the presence of a thicker, more anteriorly located lens. The UBM confirms this crowding of the anterior segment, showing the forward rotation of the ciliary processes. A gradual progressive shift in anatomic characteristics is discernible on passing from normal to chronic PACG and then to acute/intermittent PACG eyes.

Ultrasound biomicroscopic changes during accommodation in eyes with accommodating intraocular lenses: Pilot study and hypothesis for the mechanism of accommodation

Purpose: To document ciliary body constriction and movement with the Crystalens® AT‐45 intraocular lens (IOL) (eyeonics) using ultrasound biomicroscopy. Setting: Eye Clinic, Department of Neurological and Visual Sciences, University of Verona, Verona, Italy. Methods: Patients with no preexisting ocular conditions other than cataract who agreed to return for follow‐up were considered. Twenty eyes of 14 patients with a best corrected visual acuity of 5/10 or worse and a refractive error (spherical equivalent) of ±1.0 diopter (D) had implantation of a Crystalens AT‐45 accommodating IOL. Six patients had bilateral implantation. Ultrasound biomicroscopy was performed postoperatively at 1 and 6 months. Before and during accommodation, the anterior chamber depth (ACD) was measured to assess the endothelium–IOL distance and measure the scleral–ciliary process angle to determine whether there was anterior rotation of the ciliary body. The uncorrected distance acuity, best corrected distance acuity, uncorrected near acuity, distance corrected near acuity, best corrected near acuity, and accommodative amplitude were determined. Analysis was done to determine whether there was a correlation between the accommodative amplitude and the percentage variation in the ACD and scleral–ciliary process angle. Results: All surgical procedures were uneventful. The mean uncorrected distance acuity at 1 month was 0.8 ± 0.14 (SD) and remained stable at 6 months. Three of 20 eyes (15%) and 8 of 20 eyes (40%) had a Jaeger acuity of J1 and J3, respectively, without additional power correction. During accommodation, the mean reduction in ACD was 0.32 ± 0.16 mm at 1 month and 0.33 ± 0.25 mm at 6 months. The mean narrowing of the scleral–ciliary process angle was 4.32 ± 1.87 degrees at 1 month and 4.43 ± 1.85 degrees at 6 months. There was a correlation between accommodative amplitude and a decrease in the ACD (r = 0.404) and a decrease in scleral–ciliary process angle (r = 0.773). Conclusions: Anterior displacement of the Crystalens IOL and corresponding anterior rotation of the ciliary body occurred during near vision. The IOL displacement and rotation were proportional to the accommodation capacity.

Anterior segment changes during accommodation in eyes with a monofocal intraocular lens: High-frequency ultrasound study

PURPOSE: To analyze anterior segment structure changes during accommodative stimuli after monofocal intraocular lens (IOL) implantation using 2 ultrasound biomicroscopy (UBM) systems. SETTING: Department of Ophthalmology, University of Verona, Verona, Italy. METHODS: Twenty‐six eyes (23 patients) with 1 of 4 monofocal IOL types were studied. Five to 9 months postoperatively, the patients were examined by high‐frequency UBM using the HiScan system (Optikon 2000 SpA) and UBM 840 system (Carl Zeiss Meditec). Anterior chamber depth (ACD), iris–zonule distance, anterior chamber angle (ACA), scleral–ciliary process angle, and iris–ciliary process angle were measured using both systems. The iris–ciliary process distance and scleral spur perpendicular–sulcus distance were measured with the UBM 840 system and the sulcus–sulcus distance and capsular bag–IOL position with respect to ciliary process apex, with the HiScan system. Two experienced examiners performed all measurements. RESULTS: All parameters except the horizontal iris–ciliary process distance and vertical ACA measured by the UBM 840 system and horizontal ACA by the HiScan system showed significant variation during accommodation. An anterior shift of the IOL–capsular bag ciliary processes–sulcus–zonular iris complex was observed. A simultaneous centripetal shift of ciliary bodies and processes, shown by a reduction in sulcus and capsular bag diameter, was also observed. CONCLUSION: Anterior segment structures demonstrated accommodative movement on UBM after implantation of standard monofocal IOLs.

Choroidal calcification in bartter syndrome

PURPOSE Bartter syndrome is characterized by hyperplasia of the renal juxtaglomerular apparatus, hyperaldosteronism, and hypokalemic alkalosis. We report a case of Bartter syndrome associated with normal serum calcium levels and posterior choroidal calcification. METHODS Case report. A 59-year-old man with bilateral cataract and Bartter syndrome underwent a complete ophthalmic examination, including standardized echography before and after cataract surgery. RESULTS Before cataract surgery, echography identified small, hyperreflective, multifocal, bilateral choroidal lesions with posterior shadowing. After surgery, these lesions appeared as yellow-white, barely elevated plaques with smooth edges and were diagnosed as choroidal calcification. CONCLUSIONS Choroidal calcification may occur in patients with Bartter syndrome. This condition should be added to the differential diagnosis of posterior segment calcification.

Effects of 2% ibopamine on pupil, refraction, anterior segment anatomy and intraocular pressure

The aim of the study was to determine the effects of a dopaminergic drug, 2% ibopamine, on the pupil, intraocular pressure and other ocular and ultrasound biometric variables. Thirty healthy subjects and 15 patients with primary open-angle glaucoma, aged from 40 to 78 years (mean age: 59.2 +/- 11), were included in two prospective open controlled trials. In the first, the mydriatic effect of 2% ibopamine and its inhibition and reversibility were evaluated in 15 healthy subjects using the alpha1-adrenergic drug, 0.5% dapiprazole. In the second, refraction, visual acuity, pupil diameter, intraocular pressure and 5 A-scan ultrasound biometric variables were evaluated in 15 healthy subjects and in 15 glaucoma patients. As early as forty min after administration of 2% ibopamine, a marked mydriatic effect (7.3 vs 3.9 mm; P < 0.0001), which was completely inhibited or reversed by 0.5% dapiprazole, was detected. The drug induced no changes in refraction, visual acuity or A-scan ultrasound biometric variables in any of the subjects examined. In healthy subjects, the intraocular pressure values were not changed to a statistically significant extent (13.8 vs 14.8 mm Hg; P = 0.668), whereas a slight, though significant, hypertensive effect (24 vs 22.2 mm Hg; P = 0.002) was observed in the glaucoma patients. The study confirms the intense mydriatic effect of 2% ibopamine with no changes in refraction, visual acuity or A-scan ultrasound biometric variables. The drug has no effect on intraocular pressure in healthy subjects, but induces a significant hypertensive effect in patients with initial glaucoma. This characteristic could be used for early diagnosis of primary open-angle glaucoma.

Long-term outcomes of a modified technique using the Baerveldt Glaucoma Implant for the treatment of refractory glaucoma

Purpose of the Study:The purpose of the study was to evaluate the long-term effectiveness and safety profile of Baerveldt glaucoma implant (BGI) in patients with refractory glaucoma operated using a modified technique to avoid postoperative complications. Patients and Methods:A total of 160 eyes from 147 glaucomatous patients were enrolled in a consecutive interventional noncomparative case series. All the patients were treated with a 350-mm2 BGI using a modified technique. Intraocular pressure (IOP), the number of medications, the complications, and the postoperative interventions were reported preoperatively and during the follow-up. Postoperative IOP and the rate of complications were the primary outcome measures. The complete and qualified surgical success was the second endpoint. Results:BGI obtained a mean IOP reduction from 31.8±6.4 mm Hg (baseline) to 14.4±3.5 mm Hg after a mean follow-up period of 38.4±9.6 months. The mean number of medications reduced between preoperative (n=3.17±1.03) and postoperative period (n=0.58±0.83) (P<0.0001). Cumulative probability of maintaining an IOP between 5 and 21 mm Hg and/or a 25% or greater reduction in IOP was 78.7% at 1 year and 72.1% at 4 years, including 39 eyes (24.4%) in which postoperative interventions were required (qualified success). If we exclude those eyes from the analysis, the probability of complete success was 93.4% at 1 year and 91.4% at 4 years in 75.4% of the eyes. Conclusions:This modified technique achieved a high percentage of surgical success during the whole follow-up time and was effective in preventing the most serious immediate complications of nonvalved tube shunts.

Simultaneous bilateral retinal detachment following coronary artery bypass graft: Case report

Purpose To present an unusual case of simultaneous bilateral retinal detachment (RD) following a coronary artery bypass graft in a patient with acute myocardial infarction (AMI). Methods A 78-year-old man was first seen for bilateral sudden visual loss after surgical treatment of AMI. The patient underwent ultrasound biomicroscopy (UBM) and ocular B-scan echographic examination. Results The ocular assessment showed a bilateral seclusion of the pupil with bombé of the iris, an anterior chamber without cells or flare, and hypotonia. The evaluation of the visual acuity revealed no light perception in the right eye (RE) and uncertain light perception in the left eye (LE). The UBM analysis of the anterior segment confirmed the presence of bilateral pupillary block due to the seclusion of the pupil and a peripheral serous choroidal detachment involving the RE. The echographic B-scan analysis of the posterior segment showed a bilateral closed funnel-shaped RD and confirmed the presence of the peripheral flat serous choroidal detachment in RE. Conclusions The cause for simultaneous bilateral RD remained unclear. It may have been a consequence of a persistent choroidal detachment with multiple swelling and “kissing” of retinal surface. The increased venous pressure caused by congestive heart failure due to AMI could have caused a bilateral uveal effusion. Alternatively, the absence of retinal tears, the presence of a closed funnel-shaped morphology, and seclusion of the pupils allowed us to suspect an exudative pathogenetic mechanism due to a previous unrecognized ocular inflammatory state.