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Charles J. Pavlin - One of the best experts on this subject based on the ideXlab platform.
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Occult wound leak diagnosed by ultrasound Biomicroscopy in patients with postoperative hypotony
Journal of cataract and refractive surgery, 2001Co-Authors: G.w.sicco Thoe Schwartzenberg, Charles J. PavlinAbstract:Abstract Purpose To describe the ability of high-frequency ultrasound Biomicroscopy (UBM) to diagnose occult wound leaks as a cause for hypotony after cataract surgery. Methods Six patients with persistent hypotony after cataract surgery were sent for UBM examination. Slitlamp examination and gonioscopy of the 6 eyes had not revealed a cause for the hypotony. Results Ultrasound Biomicroscopy showed subtle wound separation with shallow conjunctival elevation at the site of the cataract wound in the 6 patients. Two eyes had surgical repair of the subconjunctival wound leak, and the other 4 were treated medically. In the 2 eyes with surgically repaired wounds, the hypotony cleared after wound closure. Of the 4 medically treated eyes, hypotony resolved in 2 and 1 had a recurrence of hypotony. The other 2 eyes had fluctuating intraocular pressure for an extended period. Conclusions Hypotony after cataract surgery occurred in 6 eyes due to subtle wound leaks difficult to detect by clinical observation. Ultrasound Biomicroscopy can be a helpful aid to clinical examination in detecting these leaks.
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Advances in ultrasound Biomicroscopy
Ultrasound in medicine & biology, 2000Co-Authors: F. Stuart Foster, Charles J. Pavlin, Kasia Harasiewicz, Donald A. Christopher, Daniel H. TurnbullAbstract:The visualisation of living tissues at microscopic resolution is attracting attention in several fields. In medicine, the goals are to image healthy and diseased tissue with the aim of providing information previously only available from biopsy samples. In basic biology, the goal may be to image biological models of human disease or to conduct longitudinal studies of small-animal development. High-frequency ultrasonic imaging (ultrasound Biomicroscopy) offers unique advantages for these applications. In this paper, the development of ultrasound Biomicroscopy is reviewed. Aspects of transducer development, systems design and tissue properties are pre- sented to provide a foundation for medical and biological applications. The majority of applications appear to be developing in the 40 - 60-MHz frequency range, where resolution on the order of 50 mm can be achieved. Doppler processing in this frequency range is beginning to emerge and some examples of current achievements will be highlighted. The current state of the art is reviewed for medical applications in ophthalmology, intravascular ultrasound, dermatology, and cartilage imaging. Ultrasound biomicroscopic studies of mouse embryonic devel- opment and tumour biology are presented. Speculation on the continuing evolution of ultrasound Biomicroscopy will be discussed. © 2000 World Federation for Ultrasound in Medicine & Biology.
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ultrasound Biomicroscopy of the eye
1994Co-Authors: Charles J. Pavlin, F. Stuart FosterAbstract:Ultrasound Biomicroscopy of the Eye is a comprehensive, practical guide to a new imaging technology. The development of high frequency, high resolution ultrasound imaging has given researchers and clinicians a new tool for understanding and diagnosing disease of the anterior aspect of the eye and ocular adnexa. For the first time, subsurface ocular structures can be visualized at microscopic resolution in their normal state without violating the eye. This text is written by the authors who originated and developed the technique. Topics covered in this text include an exploration of the basic principles that made this technology possible. A practical guide to technique of examination using newly available equipment is presented. Methods of measurement and values in normals are presented. A comprehensive illustrated overview is presented of the use of this technique in various forms of ocular disease, including over 300 black and white illustrations as well as a color insert. This includes the use of this technique in corneal disease, scleral disease, intraocular lens implantation, intraocular tumors, and glaucoma.
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Ultrasound Biomicroscopy in the Assessment of Anterior Scleral Disease
American journal of ophthalmology, 1993Co-Authors: Charles J. Pavlin, Michael Easterbrook, Kasia Harasiewicz, Jefferey J. Hurwitz, F. Stuart FosterAbstract:High-frequency ultrasound Biomicroscopy is a new method of examining subsurface anterior segment structures of the eye at microscopic resolution. The sclera has a high internal reflectivity and can be differentiated from the cornea, and overlying and underlying tissue. Using this modality, we examined 18 patients with various manifestations of scleral disease. Localized anterior staphyloma could be differentiated from other causes of a black spot on the scleral surface. Episcleral thickening could be differentiated from involvement of the sclera itself. Different patterns of scleral involvement could be imaged including diffuse low-reflective mottling, low-reflective nodules extending into the scleral substance, and scleral thinning. Scleral thinning could be assessed and quantified. Underlying changes in the vitreous could be detected. Ultrasound Biomicroscopy was a useful adjunct to clinical examination in the assessment of anterior scleral disease.
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An Ultrasound Biomicroscopic Analysis of Angle-closure Glaucoma Secondary to Ciliochoroidal Effusion in IgA Nephropathy
American Journal of Ophthalmology, 1993Co-Authors: Charles J. Pavlin, Michael Easterbrook, Kasia Harasiewicz, F. Stuart FosterAbstract:Immunoglobulin A nephropathy is a common glomerulonephritis of unknown cause. Episcleritis, scleritis, anterior uveitis, and keratoconjunctivitis sicca have been associated with this disease. We diagnosed angle-closure glaucoma secondary to ciliochoroidal effusion in a patient with IgA nephropathy confirmed by biopsy. High-frequency ultrasound Biomicroscopy was used to determine internal relationships of angle structures and to follow changes with treatment. Supraciliary effusion undetected by B-scan ultrasound and retinal examination was easily imaged by ultrasound Biomicroscopy. Glaucoma mechanisms included forward rotation of the ciliary processes, which caused direct angle closure in a manner similar to plateau iris. Ultrasound Biomicroscopy showed that cycloplegia improved this mechanism by retracting the ciliary processes, but angle closure secondary to forward iris bowing from pupil block remained. Iridectomy was performed and immediately opened the angle. Ultrasound Biomicroscopy proved a useful method of defining mechanisms and a helpful guide to treatment in this type of glaucoma.
F. Stuart Foster - One of the best experts on this subject based on the ideXlab platform.
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Advances in ultrasound Biomicroscopy
Ultrasound in medicine & biology, 2000Co-Authors: F. Stuart Foster, Charles J. Pavlin, Kasia Harasiewicz, Donald A. Christopher, Daniel H. TurnbullAbstract:The visualisation of living tissues at microscopic resolution is attracting attention in several fields. In medicine, the goals are to image healthy and diseased tissue with the aim of providing information previously only available from biopsy samples. In basic biology, the goal may be to image biological models of human disease or to conduct longitudinal studies of small-animal development. High-frequency ultrasonic imaging (ultrasound Biomicroscopy) offers unique advantages for these applications. In this paper, the development of ultrasound Biomicroscopy is reviewed. Aspects of transducer development, systems design and tissue properties are pre- sented to provide a foundation for medical and biological applications. The majority of applications appear to be developing in the 40 - 60-MHz frequency range, where resolution on the order of 50 mm can be achieved. Doppler processing in this frequency range is beginning to emerge and some examples of current achievements will be highlighted. The current state of the art is reviewed for medical applications in ophthalmology, intravascular ultrasound, dermatology, and cartilage imaging. Ultrasound biomicroscopic studies of mouse embryonic devel- opment and tumour biology are presented. Speculation on the continuing evolution of ultrasound Biomicroscopy will be discussed. © 2000 World Federation for Ultrasound in Medicine & Biology.
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ultrasound Biomicroscopy of the eye
1994Co-Authors: Charles J. Pavlin, F. Stuart FosterAbstract:Ultrasound Biomicroscopy of the Eye is a comprehensive, practical guide to a new imaging technology. The development of high frequency, high resolution ultrasound imaging has given researchers and clinicians a new tool for understanding and diagnosing disease of the anterior aspect of the eye and ocular adnexa. For the first time, subsurface ocular structures can be visualized at microscopic resolution in their normal state without violating the eye. This text is written by the authors who originated and developed the technique. Topics covered in this text include an exploration of the basic principles that made this technology possible. A practical guide to technique of examination using newly available equipment is presented. Methods of measurement and values in normals are presented. A comprehensive illustrated overview is presented of the use of this technique in various forms of ocular disease, including over 300 black and white illustrations as well as a color insert. This includes the use of this technique in corneal disease, scleral disease, intraocular lens implantation, intraocular tumors, and glaucoma.
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Ultrasound Biomicroscopy in the Assessment of Anterior Scleral Disease
American journal of ophthalmology, 1993Co-Authors: Charles J. Pavlin, Michael Easterbrook, Kasia Harasiewicz, Jefferey J. Hurwitz, F. Stuart FosterAbstract:High-frequency ultrasound Biomicroscopy is a new method of examining subsurface anterior segment structures of the eye at microscopic resolution. The sclera has a high internal reflectivity and can be differentiated from the cornea, and overlying and underlying tissue. Using this modality, we examined 18 patients with various manifestations of scleral disease. Localized anterior staphyloma could be differentiated from other causes of a black spot on the scleral surface. Episcleral thickening could be differentiated from involvement of the sclera itself. Different patterns of scleral involvement could be imaged including diffuse low-reflective mottling, low-reflective nodules extending into the scleral substance, and scleral thinning. Scleral thinning could be assessed and quantified. Underlying changes in the vitreous could be detected. Ultrasound Biomicroscopy was a useful adjunct to clinical examination in the assessment of anterior scleral disease.
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An Ultrasound Biomicroscopic Analysis of Angle-closure Glaucoma Secondary to Ciliochoroidal Effusion in IgA Nephropathy
American Journal of Ophthalmology, 1993Co-Authors: Charles J. Pavlin, Michael Easterbrook, Kasia Harasiewicz, F. Stuart FosterAbstract:Immunoglobulin A nephropathy is a common glomerulonephritis of unknown cause. Episcleritis, scleritis, anterior uveitis, and keratoconjunctivitis sicca have been associated with this disease. We diagnosed angle-closure glaucoma secondary to ciliochoroidal effusion in a patient with IgA nephropathy confirmed by biopsy. High-frequency ultrasound Biomicroscopy was used to determine internal relationships of angle structures and to follow changes with treatment. Supraciliary effusion undetected by B-scan ultrasound and retinal examination was easily imaged by ultrasound Biomicroscopy. Glaucoma mechanisms included forward rotation of the ciliary processes, which caused direct angle closure in a manner similar to plateau iris. Ultrasound Biomicroscopy showed that cycloplegia improved this mechanism by retracting the ciliary processes, but angle closure secondary to forward iris bowing from pupil block remained. Iridectomy was performed and immediately opened the angle. Ultrasound Biomicroscopy proved a useful method of defining mechanisms and a helpful guide to treatment in this type of glaucoma.
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Ultrasound Biomicroscopy of Anterior Segment Tumors
Ophthalmology, 1992Co-Authors: Charles J. Pavlin, John A. Mcwhae, Hugh Mcgowan, F. Stuart FosterAbstract:Background: Ultrasound Biomicroscopy is a new method of imaging the anterior segment of the eye at microscopic resolution using high frequency ultrasound. Methods: A prospective study was performed to evaluate the use of ultrasound Biomicroscopy in imaging anterior segment tumors. Forty-five patients underwent clinical examination followed by slit-lamp photography, anterior segment B-scan ultrasonography, and ultrasound Biomicroscopy according to an established protocol. Results: All lesions were clearly imaged by ultrasound Biomicroscopy, while only 17 were detectable by conventional B-scan ultrasound. Ultrasound Biomicroscopy allowed precise measurement and visualization of subsurface features in small tumors. Differentiation between solid and cystic lesions was easily achieved. The margins of ciliary body tumors could be more accurately defined. Histopathologic correlation was possible in four cases managed surgically. Ultrasound Biomicroscopy images compared favorably with low-power microscopy. No complications were encountered. Conclusion: Ultrasound Biomicroscopy proved a valuable new noninvasive technique in the evaluation of anterior segment tumors.
Robert Ritch - One of the best experts on this subject based on the ideXlab platform.
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Ultrasound Biomicroscopy in uveitis-glaucoma-hyphema syndrome.
American journal of ophthalmology, 2002Co-Authors: S Piette, Jeffrey M. Liebmann, Oscar Andrew Q Canlas, Hiroshi Ishikawa, H Viet Tran, Robert RitchAbstract:Abstract PURPOSE: To assess anterior segment anatomy in uveitis-glaucoma- hyphema syndrome. DESIGN: Retrospective case series. METHODS: Nine pseudophakic eyes (nine patients) with complete or incomplete uveitis-glaucoma-hyphema syndrome underwent ultrasound Biomicroscopy. RESULTS: Ultrasound Biomicroscopy revealed intraocular lens malposition in each case. Of the eight eyes with posterior chamber intraocular lenses, haptics were in contact with the iris pigment epithelium (four eyes) or the pars plicata (three eyes) or prolapsed into the angle recess near a filtration bleb internal ostium (one eye). All other posterior chamber intraocular lens haptics were located in the ciliary sulcus with the exception of two in the capsular bag. Both haptics in the eye with the anterior chamber intraocular lens had eroded into the ciliary body. CONCLUSION: By its ability to detect haptic position, ultrasound Biomicroscopy can assist in elucidating the cause of uveitis-glaucoma-hyphema syndrome and in deciding on the course of treatment.
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Iris and ciliary body melanomas: ultrasound Biomicroscopy with histopathologic correlation.
Archives of ophthalmology (Chicago Ill. : 1960), 2000Co-Authors: Flavio A. Marigo, Koji Esaki, Jeffrey M. Liebmann, Hiroshi Ishikawa, Paul T. Finger, Steven A. Mccormick, Raymond Iezzi, Robert RitchAbstract:Objective: To correlate ultrasound biomicroscopic images of iris and ciliary body melanomas with their histopathologic features. Methods: Ultrasound Biomicroscopy was performed in 3 cases of iris melanoma and in 3 cases of ciliary body melanoma. Cross-sectional ultrasound biomicroscopic images were compared with findings from clinical examination and light microscopy to evaluate associations between their histopathologic, surface, and internal ultrasound characteristics. Unique images of intrastomal and obscured posterior tumor margins were visualized by ultrasound Biomicroscopy. Results: Results of this study revealed that ultrasound Biomicroscopy offers an accurate method to evaluate tumor shape, reflectivity, and local invasion. Neoplastic tissue had only medium echogenicity. Enlarged vessels were correlated to echolucent spaces in the iris stroma. Anterior tumor margins were found within the iris stroma, within the anterior chamber angle, and on the endothelial surface of the cornea. Posterior tumor extension was noted to encroach onto the lens, into the sclera, and serous peripheral retinal detachments were associated with ciliary body tumors. Conclusion: Ultrasound biomicroscopic images correlated well with histopathologic features of anterior uveal melanomas including shape, reflectivity, and local extension.
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Ultrasound Biomicroscopy in Pigment Dispersion Syndrome
Ophthalmology, 1994Co-Authors: Seth D. Potash, Celso Tello, Jeffrey M. Liebmann, Robert RitchAbstract:Purpose: To examine the positional relations of the iris, lens, ciliary processes, and zonules in eyes with the pigment dispersion syndrome (PDS). Methods: High-resolution, anterior segment ultrasound Biomicroscopy was performed on 16 untreated eyes of 11 patients with PDS. Scanning was repeated on four eyes after miotic treatment and four eyes after laser iridotomy. Results: Mid-peripheral iris concavity could be demonstrated in 56%, irido-zonular contact in 25%, and irido-ciliary process contact in 75% of untreated eyes with PDS. Repeat scanning after laser iridotomy or pilocarpine therapy showed resolution of the iris concavity and irido-zonular contact in all eyes receiving these therapies. Irido-ciliary process contact persisted in some eyes. Conclusion: The authors' findings demonstrate the structural relations among the iris, lens, zonules, and ciliary processes in vivo that characterize the PDS. Miotic therapy and laser iridotomy eliminate the iris concavity in all patients with this finding, supporting the hypothesis of reverse pupillary block. Irido-ciliary process contact may be another mechanism causing release of pigment. This issue merits further clinical and histologic study.
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Measurement of Ultrasound Biomicroscopy Images: Intraobserver and Interobserver Reliability
Investigative ophthalmology & visual science, 1994Co-Authors: Celso Tello, Jeffrey M. Liebmann, Seth D. Potash, Henry Cohen, Robert RitchAbstract:PURPOSE: To evaluate intraobserver and interobserver reproducibility of measurement of images obtained during ultrasound Biomicroscopy. METHODS: Four anterior segment images of four normal patients were obtained by a single examiner. The measurements of three independent observers were compared to assess interobserver reproducibility in quantifying the images. Thirteen different anterior segment parameters were measured by each observer on each image. Intraobserver and interobserver reproducibility of measurement were assessed by calculating the coefficient of variation for each individual observer and by using the F test to detect a difference among observers. RESULTS: Intraobserver reproducibility was high. Interobserver reproducibility for the measured parameters varied considerably and was affected by subjective interpretation of visualized anatomic landmarks. CONCLUSIONS: The optimal parameters for quantitative ultrasound Biomicroscopy require refinement. Measurements of alterable parameters are best measured presently by a single observer. Ultrasound Biomicroscopy has the potential to elucidate anatomic relationships underlying much anterior segment disease, but caution in interpreting quantitative differences is warranted.
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ultrasound Biomicroscopy in plateau iris syndrome
American Journal of Ophthalmology, 1992Co-Authors: Charles J. Pavlin, Robert Ritch, Stuart F FosterAbstract:Ultrasound Biomicroscopy is a new technique that uses high-frequency ultrasound (50 to 100 MHz) to produce images of the entire anterior segment at high resolution (20 to 50 μm). The iridocorneal angle, iris, ciliary body, and posterior chamber can be imaged in detail and the dimensions and anatomic relationships of these structures determined. Plateau iris syndrome is a condition in which the angle remains appositionally closed or occludable after iridectomy for angle-closure glaucoma. How the iris remains in a position that allows it to occlude the angle has been uncertain. We performed ultrasound Biomicroscopy eye examinations on eight patients with clinically diagnosed plateau iris syndrome. In all the patients, ciliary processes were situated anteriorly compared to the position in normal subjects and in patients with angle closure caused by pupillary block. The ciliary processes provide structural support beneath the peripheral iris, preventing the iris root from falling away from the trabecular meshwork after iridectomy.
Stuart F Foster - One of the best experts on this subject based on the ideXlab platform.
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comprehensive transthoracic cardiac imaging in mice using ultrasound Biomicroscopy with anatomical confirmation by magnetic resonance imaging
Physiological Genomics, 2004Co-Authors: Yuqing Zhou, Stuart F Foster, Brian J Nieman, Lorinda Davidson, Josette X Chen, Mark R HenkelmanAbstract:High-frequency ultrasound Biomicroscopy (UBM) has recently emerged as a high-resolution means of phenotyping genetically altered mice and has great potential to evaluate the cardiac morphology and ...
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ultrasound Biomicroscopy in plateau iris syndrome
American Journal of Ophthalmology, 1992Co-Authors: Charles J. Pavlin, Robert Ritch, Stuart F FosterAbstract:Ultrasound Biomicroscopy is a new technique that uses high-frequency ultrasound (50 to 100 MHz) to produce images of the entire anterior segment at high resolution (20 to 50 μm). The iridocorneal angle, iris, ciliary body, and posterior chamber can be imaged in detail and the dimensions and anatomic relationships of these structures determined. Plateau iris syndrome is a condition in which the angle remains appositionally closed or occludable after iridectomy for angle-closure glaucoma. How the iris remains in a position that allows it to occlude the angle has been uncertain. We performed ultrasound Biomicroscopy eye examinations on eight patients with clinically diagnosed plateau iris syndrome. In all the patients, ciliary processes were situated anteriorly compared to the position in normal subjects and in patients with angle closure caused by pupillary block. The ciliary processes provide structural support beneath the peripheral iris, preventing the iris root from falling away from the trabecular meshwork after iridectomy.
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clinical use of ultrasound Biomicroscopy
Ophthalmology, 1991Co-Authors: Charles J. Pavlin, Stuart F Foster, Kasia Harasiewicz, Michael D SherarAbstract:The authors have developed a method of obtaining images of cross-sections of the intact anterior globe at microscopic resolution. High-frequency ultrasound transducers (50-100 MHz) have been developed and incorporated into a clinical B-scan device capable of producing images in the living human eye to a depth of approximately 4 mm at an axial and lateral resolution approaching 20 microns. Clinical use of this instrument is no more difficult than conventional immersion ultrasonography. The authors' results in a series of 14 clinical cases have shown that this method can provide information unavailable from any other imaging technique. Anterior segment tumors difficult to define with conventional ultrasound can be measured and the extent of invasion determined. Differentiation of tissue on the basis of internal acoustic characteristics is aided by the very fine backscatter speckle patterns at these frequencies. Pathology behind anterior segment opacities can be imaged in detail and the ability to image angle structures in cross-section allows a new quantitative method of gonioscopy. The ability to define the relationship of the iris, posterior chamber, zonules, ciliary body, and lens is potentially helpful in understanding mechanisms of glaucoma. Ocular structures can be measured with increased accuracy. Clinical ultrasound Biomicroscopy (UBM) has shown significant potential as an aid in diagnoses of ocular disease.
Hajime Inomata - One of the best experts on this subject based on the ideXlab platform.
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ultrasound biomicroscopic analysis of transient shallow anterior chamber in vogt koyanagi harada syndrome
American Journal of Ophthalmology, 1996Co-Authors: Yohichi Kawano, Akihiko Tawara, Yuko Nishioka, Yayoi Suyama, Hidehisa Sakamoto, Hajime InomataAbstract:Purpose To evaluate the mechanism of formation of the transient shallow anterior chamber in Vogt-Koyanagi-Harada syndrome. Methods Two patients with Vogt-Koyanagi-Harada syndrome with shallow anterior chambers were examined with an ultrasound biomicroscope. Results A ciliochoroidal detachment, which was not obvious on ophthalmoscopic examination, was clearly demonstrated in both patients by ultrasound Biomicroscopy. The detachment disappeared after systemic corticosteroid therapy. Conclusion The shallowing of the anterior chamber in two patients with Vogt-Koyanagi-Harada syndrome was caused by suprachoroidal effusion secondary to inflammation of the uvea.