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A 70-year-old Asian female with narrow angles underwent ultrasound biomicroscopy (UBM) darkroom provocative testing. The angle was narrow under light conditions and occluded in the dark, except for the inferior quadrant where the angle was wide and the iris concave. This was reproducible in four quadrants with the use of a small UBM eye cup but not the large one. A small eye cup can indent the cornea, resulting in artifactitious angle widenening. Care must be taken when using the small eye cup not to press on the cornea. [Ophthalmic Surg Lasers 2000;31:342-345]

* BACKGROUND AND OBJECTIVE: The commercially available optical coherence tomography (OCT) scanner displays images in a pre-set window regardless of the projected scan length on the retinal surface. The aim of this study was to demonstrate the true dimensions of proportion-corrected OCT images and the additional information present in grayscale images. * MATERIALS AND METHODS: OCT raw data were exported to an IBM-compatible PC and processed to show grayscale and proportion-corrected images using an automated software of our own design. * RESULTS: Eyes with cystoid macular edema and retinal pigment detachment were analyzed. Grayscale images showed a finer gradation of signal reflectance. Scan lengths of 2, 4, 6, and 8 mm on the retinal surface showed different qualitative appearances using proportion-corrected software from the printed or onscreen images. * CONCLUSIONS: Grayscale OCT images can be used to demonstrate additional information not present in false-color images. The disparity between the standard OCT image format and proportion-corrected images emphasizes the need for quantitative rather than qualitative evaluation of retinal dimensions and internal reflectance. [Ophthalmic Surg Lasers 2000;3 1:223-228]

To develop a reliable method for performing ultrasound biomicroscopy (UBM) in the sitting and prone positions. The probe suspended from an articulated arm was removed and reattached to the arm upside-down for use in the prone position and horizontally for use in the sitting position. A latex TonoPen tip cover was attached to the edge of the eyecup and was placed over the transducer through the small hole on the tip of the Tono-Pen tip cover. UBM was successfully performed in the prone and sitting positions with no loss of image quality. This method can expand the ability of the UBM to examine alterations in anatomic relationships among anterior segment structures between the supine, sitting, and prone positions. [Ophthalmic Surg Lasers 2000;31:166-169]

Several techniques have been described to localize and repair cyclodialysis clefts. We describe a technique that may be used to easily and accurately localize a cyclodialysis cleft using scleral transillumination. We have verified the accuracy of this technique using high frequency ultrasound biomicroscopy. The location of the cleft was verified using high frequency ultrasound biomicroscopy. Scleral transillumination may facilitate the accurate location of cyclodialysis and may be a useful adjunct in planning the surgical repair of a cyclodialysis cleft. [Ophthalmic Surg Lasers 1999;30:571-574.]

* BACKGROUND AND OBJECTIVE: To illustrate artifacts that may be encountered during measurement of the peripapillary retinal nerve fiber layer (RNFL) using scanning laser polarimetry (SLP). * PATIENTS AND METHODS: A total of 426 patients with a variety of ocular diagnoses underwent RNFL measurements using SLP from June 1996 to April 1997. Scanning was performed by two operators whose reproducibility of measurements had been previously validated. Images were selected to illustrate clinical features that adversely affected measurement of the thickness of the RNFL. * RESULTS: Image acquisition was difficult in eyes with corneal grafts or edema, keratic precipitates, anterior uveitis, posterior subcapsular cataract, vitreous opacity, peripapillary atrophy, posterior staphyloma, and high axial myopia. These scans resulted in poor clinical correlation with visual field tests and optic nerve examination, poor reproducibility of images, and unreadable images. * CONCLUSION: Anterior and posterior segment pathologies, particularly those localized to the cornea and lens, may produce spurious RNFL measurements and should be carefully considered prior to clinical decision making. [Ophthalmic Surg Lasers 1998;29:545-551.]

* BACKGROUND AND OBJECTIVE: To determine the reproducibility of retinal thickness measurements in normal eyes using optical coherence tomography (OCT). * PATIENTS AND METHODS: Multiple 3.20mm vertical cross-sectional images through the center of fixation of consecutive patients with normal results on ocular examinations were obtained. Each image was divided into seven 320-pm segments. Regional retinal thicknesses for each section were measured using both the manually assisted (requiring observer localization of reflectivity peaks) and the automated modes (observer-independent measurement) of the computer software. * RESULTS: Eighteen right eyes were studied. The mean coefficient of variation was less than 10% for all locations using the manually assisted method (average standard deviation less than 17 pm [range 9 to 16 pm]). The automated method was less reliable, with a coefficient of variation greater than 10% for locations within 500 pm of fixation. Automated measurements at fixation were the least reproducible because of poor internal limiting membrane reflectivity. * CONCLUSION: OCT is capable of reproducible measurement of retinal thickness in normal eyes. Computer-driven, automated measurement of retinal thickness within 500 pm of fixation needs to be refined and its reproducibility reassessed in this region. [Ophthalmic Surg Lasers 1998;29:280-285.]

The authors report the use of a surgical procedure for the correction of a scleral fistula in a patient with late hypotony after cataract surgery. Trephination of necrotic tissue lining the scleral fistula with a double scleral patch technique was performed. Four months later, the patients vision had improved to 20/40, with improvement of the macular folds and an intraocular pressure of 10 mm Hg. The authors conclude that the use of a double-patching technique is effective in the repair of scleral fistulas. The technique allows one to avoid more risky repair procedures that involve a greater area of tissue excision. [Ophthalmic Surg Lasers 1998;29:140-143.]

* BACKGROUND AND OBJECTIVE: The authors investigated the role of ultrasound biomicroscopy after ocular trauma. * PATIENTS AND METHODS: Ultrasound biomicroscopy was performed in six eyes of six patients at the New York Eye and Ear Infirmary after a variety of traumatic ocular injuries. * RESULTS: Eyes with angle recession, iridodialysis, cyclodialysis, hyphema, an intraocular foreign body, scleral laceration, and subluxed crystalline lens were imaged without complication. Ultrasound biomicroscopy aided in the diagnosis when visualization was limited by media opacities or distorted anterior segment anatomy. * CONCLUSION: Ultrasound biomicroscopy is a safe and effective adjunctive tool for the clinical assessment and management of ocular trauma, especially when visualization is limited and multiple traumatic injuries are involved. [Ophthalmic Surg Lasers 1997;28:201-207.]

* BACKGROUND AND OBJECTIVES: To examine anatomic relationships of anterior and posterior chamber structures in iris retraction syndrome using ultrasound bìomìcroscopy. * 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 wirh iris retraction configuration and one with iris bombe. In the latter case, iris bombe converted to iris retraction and back to Ìris 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. [Ophthalmic Surg Lasers 1996;27:257-262.]

This study compared a new disposable silicone eyecup for high-frequency ultrasound biomicroscopy to the standard hard plastic eyecup. The results showed the silicone eyecup attenuated leakage of the medium in which the probe was immersed, decreased scanning time, decreased distortion of the iris and angle during scanning, enhanced image quality, and improved patient comfort. These findings indicate the silicone eyecup is a good alternative to the hard plastic eyecup and also is easier to use. [Ophthalmic Surg Lasers Imaging 2003;34:73-75]

Preoperative evaluation and surgical planning for penetrating keratoplasty in patients with dense cornea) scars is often difficult because of poor visualization of the anterior segment. We performed ultrasound biomicroscopy (50-megahertz frequency, 50-micron resolution) on five eyes of five patients with dense corneal opacities of different etiologies to evaluate the anatomic relationships of the iris, lens, angle, and ciliary body. Corneal thickness, the presence or absence of iridocorneal adhesions, peripheral anterior synechiae, and cyclitic membranes, intraocular lens position, and relationships among intraocular structures could be evaluated in vivo. Ultrasound biomicroscopy is the optimal method of obtaining reliable, high-resolution images delineating anatomic relationships and pathology in the anterior segment. This information aids in surgical planning for penetrating keratoplasty and anterior segment reconstruction.

We report the light and electron microscopic findings from two eyes treated with argon laser peripheral iridoplasty (ALPI) for bilateral angle-closure glaucoma. The patient, a 45-year-old man, died from complications of acquired immunodeficiency syndrome 16 days following ALPI. Ocular pathologic findings included contraction furrow formation and proliferation of fibroblast-like cells, accompanied by collagen deposition on the iris surface, denaturation of stromal collagen, and coagulative necrosis of blood vessels within the anterior two thirds of the iris stroma. These findings suggest that heat shrinkage of collagen may be responsible for the short-term response to ALPI, and that contraction of the fibroblastic membrane may be responsible for its long-term effects. Additionally, the presence of coagulative necrosis of iris blood vessels suggests that overttreatment may result in iris necrosis. To our knowledge this is the first report of the histopathology of ALPI.

* 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 of 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 imaging, 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. [Ophthalmic Surg Lasers 1996;27:97-105.]

Sub-Tenon's anesthesia for anterior segment surgery avoids the risks associated with retrobulbar and peribulbar injections. Localized injections over the appropriate rectus muscles ensure patient comfort as well as optimal exposure of the surgical field in eyes undergoing trabeculectomy. We have used this technique without significant complications in approximately 400 procedures.

A new conjunctival retractor provides the desired exposure of the scleral bed during filtering surgery. It elevates the conjunctiva without causing crush injury and allows excellent exposure of the scleral bed with a smaller incision than is required when non-toothed forceps or Week cell sponges are used. The surgeon or assistant holding the retractor can move it in various directions to provide a good view of any particular site for which exposure is needed. [Ophthalmic Surg Lasers Imaging 2004;35:261-262.]

Peter s anomaly is a congenital corneal disorder characterized by a central leukoma and adhesions at the periphery of the corneal opacity. A 35-year-old man presented for clinical evaluation of suspected sclerocornea. High-resolution ultrasound biomicroscopy revealed iridocorneal adhesions throughout the anterior segment, a shallow anterior chamber, and abnormal hyper-reflectivity along the posterior corneal surface. Through ultrasound biomicroscopy, characteristics of Peter's anomaly were recognized, and a diagnosis was established. This case illustrates how ultrasound biomicroscopy aids in the clinical differentiation between Peter's anomaly and other causes of congenital corneal opacification. [Ophthalmic Surg Lasers 1997;28:311-312.]

Argon laser suture lysis is a valuable adjunct for regulating intraocular pressure and establishing a filtration bleb in the early postoperative period after trabeculectomy. We have developed a lens that provides excellent compression of the conjunctiva, an improved view of scleral flap sutures, and effortless retraction of the upper lid.

A choroidal effusion, hypotony, and a shallow anterior chamber developed in a patient following a transconjunctival needling revision of an encapsulated filtering bleb. While choroidal effusions occur frequently following filtration surgery, to our knowledge, this complication has not been previously reported following a filtering bleb needle revision.

We describe a technique of internal suture ligation of the tube of the Molteno seton to prevent hypotony in the immediate postoperative period, without risking infection or inflammation.

Laser iridectomy relieves pupillary block and is the procedure of choice for angle-closure glaucoma. Since not all cases of angle closure glaucoma are due to this mechanism, iridectomy is not always curative. Argon laser peripheral iridoplasty causes a contraction of peripheral iris away from the trabecular meshwork, and is useful in these circumstances. We successfully treated bilateral acute angle-closure glaucoma in a patient with acquired immunodeficiency syndrome with this procedure.

Filtering surgery may be complicated by excessive filtration or bleb leak in the postoperative period, resulting in a shallow or flat anterior chamber and choroidal detachment. A glaucoma tamponade shell with a raised inner platform increases the resistance to flow through the fistula, deepening the anterior chamber. Some surgeons apply a pressure patch over the shell to increase the tamponading effect and to prevent rotation of the shell. Nevertheless, the shell may still rotate, resulting in less than adequate tamponade. We describe a technique that prevents rotation of the shell.