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J M Liebmann

Publications and source records attributed to J M Liebmann.

At least 91 records · Page 5Linked to original sources
PubMed1996

Repair of Descemet's membrane detachment with the assistance of intraoperative ultrasound biomicroscopy.

PURPOSE: To evaluate the ability of ultrasound biomicroscopy to monitor the repair of large Descemet's membrane detachments. METHODS: Intraoperative ultrasound biomicroscopy was performed in two patients who had undergone previous unsuccessful surgical repair of large Descemet's membrane detachments. RESULTS: Ultrasound biomicroscopy visualized and located Descemet's membrane detachment and verified proper suture placement and membrane repositioning. CONCLUSIONS: Ultrasound biomicroscopy is a useful tool to guide surgical repair of Descemet's membrane detachments, particularly when hazy media prevent satisfactory visualization.

Aged↗
PubMed1996

Increase in iris-lens contact after laser iridotomy for pupillary block angle closure.

PURPOSE: To quantitate changes in anterior ocular segment anatomy after laser iridotomy for pupillary block angle closure. METHODS: We prospectively performed ultrasound biomicroscopy and A-scan biometry in 13 eyes of 13 consecutive untreated patients with relative pupillary block and appositional angle closure, without peripheral anterior synechiae on indentation gonioscopy. A radial, perpendicular image in the horizontal temporal meridian was obtained with ultrasound biomicroscopy before and one week after laser iridotomy in each eye. RESULTS: Mean age of the 13 patients was 69.3 +/- 1.8 (S.E.) years, mean refractive error was +1.37 +/- 0.39 diopters, and mean axial length was 22.54 +/- 0.20 mm. In 13 eyes, before and after laser iridotomy measurements of angle-opening distance (0.11 +/- 0.02 vs. 0.18 +/- 0.02 mm) (P = .0004; paired t test), angle aperture (8.3 +/- 1.3 vs 18.6 +/- 2.8 degrees) (P = .0003) and iris-lens contact distance (0.58 +/- 0.06 vs 1.18 +/- 0.14 mm) (P = .0003) were greater postoperatively, but anterior chamber depth was unchanged (P = .7). CONCLUSIONS: Flattening of the iris after laser iridotomy for pupillary block causes an increase in iris-lens contact. The change in angle configuration after iridotomy results more from an alteration in aqueous pressure gradients across the iris rather than from posterior lens movement.

Aged↗
PubMed1996

Risk factors for ciliochoroidal effusion after panretinal photocoagulation.

PURPOSE: To determine the incidence, duration, and risk factors for ciliochoroidal effusion after panretinal photocoagulation. METHODS: Thirty-nine consecutive patients with diabetic retinopathy underwent ultrasound biomicroscopy of both eyes to image the ciliochoroidal space immediately before and 1 day after unilateral argon-green panretinal photocoagulation. Imaging was repeated on days 3, 7, and 14 in patients in whom ciliochoroidal effusion developed. RESULTS: Low-lying ciliochoroidal effusions were imaged in 23 (59%) of 39 eyes. Of 23 eyes, effusions resolved in 6 (26%), 12 (52%), and 5 (22%) eyes by 3, 7, and 14 days respectively. The number of laser applications (P = 0.02), shorter axial length (P = 0.01), and percentage of retinal surface area treated (P = 0.02) were associated with systemic hypertension, location of treatment, previous panretinal photocoagulation of cataract surgery, retinal surface area treated, and mean blood pressure before photocoagulation were not associated with effusion. All fellow, untreated eyes remained effusion-free. CONCLUSION: Ciliochoroidal effusion develops commonly after panretinal photocoagulation. Limiting the number of laser applications and the percentage of retinal surface area treated reduces the likelihood of this complication. Eyes with shorter axial lengths are at higher risk

Adult↗
PubMed1996

Location of the iris insertion in pigment dispersion syndrome.

PURPOSE: To evaluate the position of the iris insertion into the ciliary body in persons with pigment dispersion syndrome (PDS) and control subjects. METHODS: Ultrasound biomicroscopy was performed on 19 eyes with PDS and on 21 eyes of control subjects. A radial, perpendicular image in the temporal meridian detailing Schwalbe line (SL), scleral spur (SS), and iris root insertion (IR) was obtained for each eye by a single examiner. The distances between these structures then was measured. RESULTS: There were no differences between the groups in refractive error (mean +/- standard error, -2.8 +/- 0.7 diopters for PDS eyes versus -2.2 +/- 0.6 for control subjects) (P=0.46), sex distribution (P=0.49), and trabecular meshwork height (SL to SS) (0.63 +/- 0.03 mm [PDS eyes] versus 0.59 +/- 0.03 [control eyes]; P = 0.24). The SS-to-IR distance was significantly greater in PDS eyes (0.04 +/- 0.04 mm) than in control eyes (0.28 +/- 0.04 mm) (P=0.01) as was the overall distance from SL to IR (0.98 +/- 0.04 mm versus +/- 0.04 mm) (P = 0.003). CONCLUSION: The insertion of the iris into the ciliary body is more posterior in PDS eyes than in control eyes. This anatomic variation places the iris pigment epithelium proximal to the zonular apparatus and may increase the likelihood of iridozonular contact and zonular pigment dispersion.

Adolescent↗
PubMed1996

Ciliary body enlargement and cyst formation in uveitis.

BACKGROUND: Acute anterior uveitis has diverse causes and systemic associations. Inflammation is predominantly localised to the iris and pars plicata. Little is known about the in vivo effects of uveitis on ciliary body anatomy. METHODS: Bilateral, high frequency, high resolution, ultrasound biomicroscopy was performed on consecutive patients with unilateral anterior uveitis to evaluate ciliary body anatomy. Imaging was repeated when possible during the clinical course. The cross sectional area of the anterior ciliary body was measured using image processing and analysis software. Measurements from the uveitic eyes were compared with the fellow eyes and the effect of treatment was evaluated. RESULTS: Fourteen patients were enrolled. Ultrasound biomicroscopy demonstrated a larger ciliary body cross sectional area in the uveitic eyes compared with the fellow, clinically uninvolved eyes (2.45 (SD 0.48) mm2 versus 1.55 (SD 0.15) mm2, (p = 0.0000; paired t test)). A ciliochoroidal effusion was present in one uveitic eye. Epithelial cysts were imaged bilaterally in four uveitic patients (29%) and unilaterally in unaffected eyes of two uveitic patients. Ciliary body cross sectional area decreased following steroid therapy (p = 0.0001; paired t test). New cysts were noted in three uveitic eyes during the follow up period and in none of the fellow, unaffected eyes. CONCLUSION: Ultrasound biomicroscopy offers a new approach to the evaluation of anterior uveitis. The response to treatment can be evaluated objectively and therapeutic efficacy can be more easily assessed. It has the potential to help elucidate the pathophysiology and anatomical changes of this heterogeneous group of disorders.

Adolescent↗
PubMed1996

In vivo increase of the human lens equatorial diameter during accommodation.

The movement of the human lens equator during accommodation was examined in vivo. High-resolution ultrasound images of the lens equator were obtained from young human subjects whose amplitude of accommodation was controlled with 1% tropicamide and 2% pilocarpine. To avoid errors that otherwise arise from eye rotation or other movement, the cornea and sclera were used as positional references in comparative studies of the video images obtained from the unaccommodated and accommodated states. During accommodation, the movement at the lens equator involved small displacement; i.e., < 100 microns, and the equator did not move anteriorly or posteriorly but peripherally toward the sclera. These results indicate that the lens equator is under increased zonular tension during accommodation, in contradiction to Helmholtz's widely accepted theory of accommodation.

Accommodation, Ocular↗
PubMed1996

Diagnosis of traumatic cyclodialysis by ultrasound biomicroscopy.

BACKGROUND AND OBJECTIVE: To evaluate the ability of high-frequency ultrasound biomicroscopy to diagnose traumatic cyclodialyses not evident on clinical examination. PATIENTS AND METHODS: Six eyes to six patients with posttraumatic hypotony and/or shallow anterior chamber and suspected cyclodialysis clefts were examined with slit-lamp biomicroscopy, gonioscopy, B-scan ultrasonography, and ultrasound biomicroscopy. Ultrasound biomicroscopy provided high resolution of cross-sectional images of the anterior chamber angle, posterior chamber, and anterior uveal tissue. RESULTS: Ultrasound biomicroscopy confirmed the disinsertion of the ciliary body from the scleral spur and associated ciliary body detachment in all eyes. Gonioscopy failed to demonstrate a cyclodialysis cleft in five eyes because of hyphema (two eyes) and abnormal iris architecture (related to trauma) precluding visualization of the angle recess (three eyes). Using information from ultrasound biomicroscopy imagining, one patient underwent a ciliary body reattachment procedure and repair of the cyclodialysis cleft. CONCLUSION: Ultrasound biomicroscopy is a noninvasive method that can accurately diagnose the presence of traumatic cyclodialyses and can aid in surgical management. It is particularly useful in the presence of hazy media, hypotony, and/or abnormal anterior segment anatomy.

Adolescent↗
PubMed1996

Ultrasound biomicroscopic features of iris retraction syndrome.

BACKGROUND AND OBJECTIVES: To examine anatomic relationships of anterior and posterior chamber structures in iris retraction syndrome using ultrasound biomicroscopy. PATIENTS AND METHODS: Four eyes of four patients with iris retraction syndrome were imaged using high-frequency, high-resolution, anterior segment ultrasound biomicroscopy. In two patients, scans were obtained before and after medical therapy. RESULTS: Three patients presented with iris retraction configuration and one with iris bombe. In the latter case, iris bombe converted to iris retraction and back to iris bombe with the administration and later withdrawal of aqueous suppressants. Ciliochoroidal effusion was present in all eyes. CONCLUSIONS: Ciliochoroidal effusion is a constant feature of iris retraction syndrome. The hypotony associated with this disorder may result in part from aqueous hyposecretion related to ciliary body detachment. Ultrasound biomicroscopy is a useful aid in the diagnosis and follow-up of eyes with iris retraction syndrome.

Adult↗
PubMed1996

Laser iridotomy.

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Acute Disease↗
PubMed1996

Ultrasound biomicroscopy of the anterior segment.

BACKGROUND: New imaging technologies are revolutionizing the understanding and treatment of a wide variety of ocular disorders. Confocal scanning laser ophthalmoscopy, ultrasound biomicroscopy, confocal scanning laser polarimetry, color doppler imaging of blood flow, and optical coherence tomography are providing important information regarding disease pathophysiology, diagnosis, progression, and treatment. METHODS: High frequency (50 MHz), high resolution ultrasound biomicroscopy of the anterior segment was obtained in a wide variety of disorders of the anterior segment. Tissue resolution is approximately 50 microns and the penetration depth is 5 mm. RESULTS: Ultrasound biomicroscopy is capable of imaging the comea, iris, anterior chamber, anterior chamber angle, posterior chamber, and ciliary body with great detail. The structures surrounding the posterior chamber, previously hidden from clinical observation, can be imaged and their normal anatomic relationships assessed. The various forms of angle closure glaucoma, such as pupillary block and plateau iris configuration, can be differentiated. The concave iris found in pigment dispersion and its response to treatment can be assessed. Visualization of anterior segment anatomy in eyes with opaque media is possible. CONCLUSIONS: Ultrasound biomicroscopy assists in the management of eyes with disorders of the anterior segment. Future applications of this technology will yield important information regarding accommodation, normal ocular physiology and disease pathophysiology.

Anterior Eye Segment↗
PubMed1995

Prevention of blinking alters iris configuration in pigment dispersion syndrome and in normal eyes.

PURPOSE: To examine the effect of blinking on iris configuration and aqueous humor distribution between the posterior and anterior chambers in eyes with pigment dispersion syndrome compared with healthy eyes. METHODS: High-resolution, anterior segment ultrasound biomicroscopy was performed on ten eyes of ten patients with untreated pigment dispersion syndrome and on ten control subjects. Patients were scanned continuously for 15 minutes or until the maximal change in iris configuration occurred. During this time, the eyelids were held open mechanically, and blinking was prevented. Eyes then were rescanned immediately after blinking. RESULTS: Initial iris configuration was concave in all eyes with pigment dispersion syndrome, whereas in control eyes it was concave in four eyes, planar in four eyes, and convex in two eyes. Iridozonular contact occurred in eyes with pigment dispersion syndrome only. Iridolenticular contact was greater in eyes with pigment dispersion syndrome than in control eyes. Analysis of covariance controlling for age, sex, and refractive error showed pigment dispersion syndrome to be a significant predictor of increased iris concavity. During continuous scanning, the mean change in iris position, from most concave to most convex, and mean time to the maximal change in iris configuration were greater for eyes with pigment dispersion syndrome than in control eyes and were related to the degree of initial iris concavity only (analysis of covariance). In six eyes with pigment dispersion syndrome, the eye cup was removed, normal blinking was permitted, and the eye was rescanned. The iris resumed a concave configuration in all eyes. CONCLUSION: Increased iris concavity in pigment dispersion syndrome appears to be related to increased iridolenticular contact. This creates an anatomic configuration that predisposes to reverse pupillary block. The accumulation of aqueous humor in the posterior chamber, when blinking is prevented, alters iris position in pigment dispersion syndrome and in healthy eyes and increases iridozonular and iridociliary-process distances while minimizing iridolenticular contact. Normal blinking appears to create transient vector forces which promote aqueous humor flow from the posterior to anterior chamber.

Adult↗
PubMed1994

5-Fluorouracil after primary combined filtration surgery.

We examined the safety and efficacy of 5-fluorouracil in eyes with open-angle glaucoma undergoing combined cataract removal and filtration surgery. We randomly assigned one eye each of 24 patients to receive 5-fluorouracil (five injections of 5 mg during two weeks after surgery) and one eye each of 20 patients to comprise the control group. Preoperatively, the two groups had similar mean intraocular pressure (P = .8) and number of medications (P = .2). The mean intraocular pressure of the 5-fluorouracil group was 18.6 +/- 1.1 mm Hg, with 2.5 +/- 0.3 medications; that of the control group was 18.2 +/- 1.2 mm Hg, with 2.2 +/- 0.2 medications. One year postoperatively, intraocular pressure and the number of medications were significantly reduced by a similar amount in both groups of patients (5-fluorouracil, 14.2 +/- 0.7 mm Hg, 0.8 +/- 0.2 medications; controls, 14.3 +/- 0.6 mm Hg, 1.0 +/- 0.2 medications). Transient superficial punctate keratopathy occurred more frequently (P = .04) in the 5-fluorouracil group (16 of 24 eyes, 67%) than in the control group (seven of 20 eyes, 35%). In our randomized and prospective study, the adjunctive use of 5-fluorouracil did not result in improved control of intraocular pressure one year after combined surgery in eyes with open-angle glaucoma.

Aged↗
PubMed1994

5-Fluorouracil in initial trabeculectomy. A prospective, randomized, multicenter study.

PURPOSE: Postoperative subconjunctival 5-fluorouracil (5-FU) injections increase the success of filtration surgery in eyes with prior filtration failure or cataract removal and in eyes with secondary glaucoma. The authors evaluate the safety and benefit of adjunctive 5-FU in eyes undergoing initial trabeculectomy. METHODS: Patients with phakic, uncontrolled, open-angle glaucoma who were undergoing initial trabeculectomy were prospectively assigned to the 5-FU group on the first postoperative day. Patients in this group received five 5-mg injections during 2 weeks after surgery. Patients in the control group received no injections. RESULTS: Preoperative intraocular pressure (IOP) and number of antiglaucoma medications were similar in the 5-FU (n = 32) and control (n = 30) groups. Transient superficial punctate keratopathy was the only postoperative complication that occurred more frequently (P < 0.05) in the 5-FU (14 eyes) than in the control eyes (3 eyes). Patients were followed for a minimum of 1 year or until a study endpoint was reached: IOP of 21 mmHg or greater with maximum medical therapy (2 5-FU eyes and 8 control eyes; P < 0.03) or cataract removal after filtration (5 treated and 3 control eyes). At last follow-up (mean, > 20 months), IOP and the number of antiglaucoma medications were significantly lower (P < 0.02) in the 5-FU eyes (IOP, 12.0 +/- 1.3 mmHg; medications, 0.2 +/- 0.1) than in the control eyes (IOP, 16.8 +/- 1.3 mmHg; medications, 0.8 +/- 0.2). Intraocular pressure was 20 mmHg or lower in 94% of 5-FU eyes and in 73% of control eyes (P < 0.03) and 16 mmHg or lower in 84% of 5-FU eyes and in 57% of control eyes (P < 0.02). CONCLUSIONS: Adjunctive 5-fluorouracil increases the rate of success, decreases the level of postoperative IOP, and reduces the need for postoperative antiglaucoma medication in eyes with open-angle glaucoma undergoing initial trabeculectomy.

Aged↗
PubMed1994

Reconstruction of filtering blebs with free conjunctival autografts.

BACKGROUND: Situations arise in which the surgical repair or revision of filtering blebs is either technically impossible or inadequate, and total reconstruction becomes necessary. This is most frequently encountered in eyes that have undergone multiple procedures, resulting in significant bulbar conjunctival scarring and episcleral fibrosis. METHODS: To preserve the pre-existing filtration site, the authors successfully treated five such patients in whom conjunctival scarring adjacent to and surrounding the blebs precluded local revision, by transplanting free conjunctival autografts. Two patients required grafting from the fellow eye. Specific modifications from previously reported conjunctival flap techniques were used to enhance graft healing and continued filtration. RESULTS: Satisfactory intraocular pressure control was maintained in all patients receiving minimal to no anti-glaucomatous medications with an average follow-up of 42.6 months (range, 7-90 months). No patient had a significant decrease in visual acuity or surgical complications. CONCLUSION: Free conjunctival autografting techniques are a useful adjunct in the surgical revision of leaking, failed, or migrating filtration blebs.

Aged↗