L. Bonomi

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.

Secondary implantation of angle-supported anterior chamber and scleral-fixated posterior chamber intraocular lenses

Purpose: To compare the results of secondary implantation of angle‐supported anterior chamber intraocular lenses (IOLs) and scleral‐fixated posterior chamber lenses. Setting: Eye Clinic, University of Verona, Italy. Methods: This study of 68 eyes of 60 patients comprised two groups. In Group A (n = 35), an angle‐supported anterior chamber IOL was implanted and in Group B (n = 33), a scleral‐fixated posterior chamber IOL. Follow‐up was from 12 to 45 months. Results: In Group A, one eye developed a retinal detachment and another, pseudophakic bullous keratopathy. In Group B, one eye had a major intraoperative choroidal hemorrhage and two developed a retinal detachment postoperatively. All other complications were minor. Conclusion: Although the rate of sight‐threatening complications was about 6% for both groups, scleral‐fixated posterior chamber IOLs were associated with more intraoperative and postoperative complications than angle‐fixated anterior chamber IOLs, and surgery took longer. Thus, anterior chamber IOL implantation should be considered for older patients with relatively good endothelial cell counts.

Ultrasound biomicroscopy and intraocular-pressure-lowering mechanisms of deep sclerectomy with reticulated hyaluronic acid implant

Purpose: To evaluate the anatomic characteristics and intraocular pressure (IOP) lowering mechanisms of deep sclerectomy with reticulated hyaluronic acid implant (DS with RHAI) using ultrasound biomicroscopy (UBM). Setting: Eye Clinic, Department of Neurological and Vision Sciences, University of Verona, Verona, Italy. Methods: Thirty patients with primary open‐angle glaucoma not controlled by medical therapy had DS with RHAI in 1 eye. A complete ocular examination and UBM study were performed 1, 3, 6, and 12 months postoperatively and thereafter at 6 month intervals. Eleven parameters were evaluated, the most important of which were IOP, surgical success in lowering IOP to 21 mm Hg or less with or without additional medical therapy, UBM appearance of the site of DS with RHAI, size of the decompression space, presence of a filtering bleb and supraciliary hypoechoic area, and scleral reflectivity around the decompression space. Results: After a mean follow‐up of 11.4 months ± 4.7 (SD), the mean percentage reduction in IOP compared to preoperatively was 38% (from 26 ± 4.5 mm Hg to 16.2 ± 3.8 mm Hg; P = .0001). Twenty‐four patients (80%) had an IOP less than 21 mm Hg; however, 7 of these eyes (23%) required additional IOP‐lowering medical therapy. The operation failed in 6 patients (20%) despite additional therapy. Ultrasound biomicroscopy revealed a reduction in the size of the decompression space from 6 months postoperatively and its disappearance in 2 cases. The difference in size at the last follow‐up and at 1 month postoperatively (maximum length 2.41 ± 1.02 mm versus 3.53 ± 0.51 mm) was significant (P = .0001). At the last examination, a filtering bleb was present in 18 patients (60%), a supraciliary hypoechoic area in 18 (60%), and hyporeflectivity of the scleral tissue around the decompression space in 14 (47%). These 3 UBM characteristics were detected singly and in various combinations. The simultaneous presence of all 3 characteristics in the same eye correlated significantly with a higher surgical success rate (P = .004). Conclusions: Ultrasound biomicroscopy showed that filtering bleb formation was frequent in eyes having DS with RHAI but that it was not the only surgically induced IOP‐lowering mechanism. Increased uveoscleral and transscleral filtration may be equally important.

Gamma Knife Stereotactic Radiosurgery for Uveal Melanoma: Clinical Results after 2 Years

We report on 36 cases of uveal melanoma treated at our center between March 1993 and September 1995. There were 16 men and 20 women, aged 57 +/- 11 years. The choroid was affected in 35 patients and the ciliary-body in 1. The same preoperative and follow-up protocol was adopted for all cases. The procedure included fixation and positioning of the eye with a retrobulbar injection of long-lasting anesthetic and two extraocular muscle sutures, application of the frame, computed tomography scan localization, dose planning and treatment with the Gamma Knife. The patients were divided into three groups. Group A: 10 patients with a follow-up of 24 +/- 4 months, treated with a high dose (surface dose 58 +/- 9 Gy, maximum dose 81 +/- 15 Gy, mean dose 66 +/- 11 Gy). Group B: 9 patients with a follow-up of 16 +/- 2 months, treated with a lower dose (surface dose 41 +/- 3 Gy, maximum dose 76 +/- 10 Gy, mean dose 53 +/- 11 Gy). Group C: 17 patients with a follow-up of 6 +/- 3 months, treated with a lower dose (surface dose 42 +/- 3 Gy, maximum dose 72 +/- 16 Gy, mean dose: 54 +/- 6 Gy). In group A, we observed marked tumor regression in 9 cases, tumor recurrence in 1 case and severe complications in 5 cases (neovascular glaucoma and/or radiation retinopathy and/or radiation optic neuropathy). In group B, significant local control of the tumor was obtained with minor complications (cotton wool spots hard exudates, intraretinal hemorrhages). In group C, to date we have observed a regression of the tumor in 7 cases and 1 severe complication (neovascular glaucoma). Our data show that uveal melanomas may be adequately controlled by a high radiosurgical dosage (50-70 Gy), though there are significant side effects. Comparable levels of local tumor control may be obtainable using lower doses (40-45 Gy) which would hopefully reduce the rate of complications. However, a longer follow-up is needed for further validation of these results.

Perimetric defects after a single acute angle-closure glaucoma attack

Abstract · Background: This study was carried out to determine the effect of an acute attack of angle-closure glaucoma on the visual field. · Methods: A total of 53 eyes were examined 36–48 h after remission of an acute glaucoma attack by means of computerised perimetry (Humphrey 630 perimeter, 30-2 program). Perimetry was repeated after at least 1 month in 22 eyes. · Results: Perimetric defects, varying greatly in severity and primarily of the generalised type or concerning at least wide sectors of the field, were detected in 45 (85%) of 53 cases. The visual field was normal in the remaining 8 patients (15%). The upper nasal quadrants were the most frequently affected and the degree of eccentricity was most frequently involved within the 9°–21° area. In 7 of the 22 cases in which perimetry was repeated after 1 month, complete normalisation was noted in the visual field. · Conclusions: An isolated attack of acute glaucoma produces in most cases a perimetric defect of generalised or mixed type. This may be reversible. The most affected zones were the upper half of the visual field and the 9°–21° area.

Molecular Epidemiology in a Cluster of Cases of Postoperative Pseudomonas aeruginosa Endophthalmitis

Between September and October 1994 we observed three cases of Pseudomonas aeruginosa endophthalmitis in a single ophthalmology center. Endophthalmitis progressed rapidly following surgical intervention, and the three patients completely lost vision in the affected eye. Microbiological surveillance culture specimens were obtained from environmental sites, the operating team, intraocular lenses, irrigation fluids, and surgical equipment. P. aeruginosa was isolated from the internal tubing system of automated cataract surgical equipment. The strains of P. aeruginosa cultured from vitreous and anterior chamber specimens of case patients and from the surgical equipment were analyzed with pulsed-field gel electrophoresis. Genomic DNA typing of these isolates showed an identical banding pattern on ethidium bromide-stained gels. We believe that this is the first reported outbreak of P. aeruginosa endophthalmitis traced to automated surgical equipment. Genomic DNA typing emerged as a practical and reliable option for the epidemiological investigation of the outbreak.

Stereotactic Radiosurgery of Uveal Melanomas: Preliminary Results with Gamma Knife Treatment

Twelve cases of uveal melanoma (T3N0M0:11 patients, T4N0M0:1 patient) treated with Gamma Knife stereotactic radiosurgery are reported. Our protocol includes preoperative ocular and systemic assessments with complete ocular examination, ophthalmoscopy, fundus photography, fluorangiography, standardized echography, CT and MRI, chest X-rays, liver echography and blood tests. The follow-up program is mainly based on echographic evaluation of tumor thickness and size. The procedures include fixation of the eye, application of the stereotactic Leksell frame G, CT/MRI localization of the melanoma, dose planning and treatment with the Gamma Knife (B type). A mean surface dose of 55 +/- 10 Gy was administered at the 60-90% isodose curve using 4- to 14-mm collimators and a number of shots ranging from 1 to 6. A significant reduction (10-41%) in echographic thickness of the tumor was shown in 6 cases with a follow-up of 3-12 months. In 4 patients, the tumor size was still unchanged after 1-10 months. The single high-dose radiation delivered to the target and the high spatial accuracy are the main advantages of stereotactic radiosurgery for the treatment of posterior uveal melanomas. A longer followup is needed to further validate this new application of Gamma Knife radiosurgery.

Does Nerve Fiber layer thickness correlate with visual field defects in glaucoma : A study with the Nerve Fiber Analyzer

The Nerve Fiber Analyzer, a confocal scanning laser ophthalmoscope, was used to measure the thickness of the retinal nerve fiber layer (NFL) in a glaucoma population. The authors studied the correlation between NFL thickness and the perimetric defects. The NFL was found to be statistically thinner in comparison to a normal control group of subjects. The correlation between the perimetric index MD and the NFA was statistically significant only for the lower quadrant of retinal NFL. The correspondence between thinner NFL and perimetric defects was investigated.

Evaluation of the 701 interzeag lens opacity meter

The Interzeag 701 Lens Opacity Meter was used to study the lenses of 122 cataract eyes and 73 healthy eyes with clear lenses. The readings taken separately in 67 eyes by two different operators did not significantly differ. Statistically significant differences were found between the readings taken by the same operator when the pupil size was different in all types of cataract and also in eyes with transparent lenses. Opacity Meter readings correlate well with the visual acuity of eyes with nuclear and mixed cataracts, but no correlation was found in eyes with cortical or posterior subcapsular cataracts. In healthy eyes with clear lens, a correlation was found between the instrument readings and age.

Gamma Knife Stereotactic Radiosurgery of Ocular Metastases: A Case Report

A case of a choroidal metastasis treated with Gamma Knife stereotactic radiosurgery is reported. A 48-year-old Caucasian man afflicted with lung cancer (adenocarcinoma) was referred to the University Hospital of Verona, Italy, for loss of vision in his left eye due to a choroidal mass with exudative retinal detachment. Clinical investigation was conclusive of a well-defined, bilobed choroidal metastasis located in the temporal and inferior portion of the posterior pole of the eye. The lesion was characterized by a maximum thickness of 5.2 mm and a maximum lateral extension of 14 mm. The staging was negative for other metastatic localizations. Using the Gamma Knife technique, a surface dose of 25 Gy was administered at the 50% isodose line using the 8-mm collimator (5 shots) with equally weighted fields. After a 3-month follow-up period, a marked reduction in the lesion size as well as in the exudative retinal detachment was observed. This improvement was unchanged 6 months after the treatment, and the lesion appeared completely controlled. To the best of our knowledge, this is the first case report of an ocular metastasis treated with stereotactic Gamma Knife radiosurgery.