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Descemet's Stripping Endothelial Keratoplasty (DSEK) and Glaucoma
Chapter by: Filippopoulos, Theodoros; Colby, Kathryn A.; Grosskreutz, Cynthia L.
in: GLAUCOMA BOOK: A PRACTICAL, EVIDENCE-BASED APPROACH TO PATIENT CARE by
pp. 885-888
ISBN: 978-0-387-76699-7
CID: 4501582
The white caruncle: sign of a keratinous cyst arising from a sebaceous gland duct [Case Report]
Jakobiec, Frederick A; Mehta, Manisha; Greenstein, Scott H; Colby, Kathryn
PURPOSE/OBJECTIVE:To describe an acquired, smooth white lesion of the caruncle and to underscore the role of subsurface keratinizing squamous epithelium in its formation. METHODS:Clinical photographic documentation, histopathologic evaluation, and immunohistochemical staining of an excised specimen from a 25-year-old woman. RESULTS:A cyst was found that was lined by keratinizing squamous epithelium without a keratohyaline layer (trichilemmal keratinization), typical of lesions of the pilosebaceous unit. A portion of the cyst's lining was replaced by granulomatous inflammation resulting from an earlier spontaneous partial rupture. Ki-67 immunolabeling demonstrated relatively few nuclei in S-phase (DNA synthesis) in comparison with the overlying epithelium, thereby suggesting an obstructive, nonproliferative cause for the cyst. CONCLUSION/CONCLUSIONS:A white caruncular lesion is a very rare finding according to the literature. It is most likely caused by a cyst lined by squamous epithelium elaborating trichilemmal-type keratin. A sebaceous gland duct was established as the source for the current lesion.
PMID: 20164755
ISSN: 1536-4798
CID: 4500922
Boston Ocular Surface Prosthesis for persistent epitheliopathy after treatment of conjunctival melanoma [Case Report]
Grover, Surbhi; Jacobs, Deborah S; Colby, Kathryn A
PURPOSE/OBJECTIVE:To report two cases of persistent epitheliopathy after treatment of conjunctival melanoma and review management options for this condition. METHODS:Case report and literature review. RESULTS:Persistent epitheliopathy, presumably resulting from limbal stem cell deficiency, is an uncommon complication of treatment of conjunctival malignant melanoma with surgical excision, cryotherapy, and mitomycin C. The Boston Ocular Surface Prosthesis was successful in improving vision, comfort, and epithelial status in our patients. CONCLUSION/CONCLUSIONS:Persistent epitheliopathy is a rare complication of treatment of conjunctival melanoma. The Boston Ocular Surface Prosthesis is a viable treatment option in this situation.
PMID: 20164756
ISSN: 1536-4798
CID: 4500932
Electronic energy migration on different time scales: concentration dependence of the time-resolved anisotropy and fluorescence quenching of Lumogen Red in poly(methyl methacrylate)
Colby, Kathryn A; Burdett, Jonathan J; Frisbee, Robert F; Zhu, Lingyan; Dillon, Robert J; Bardeen, Christopher J
Electronic energy transfer plays an important role in many types of organic electronic devices. Forster-type theories of exciton diffusion provide a way to calculate diffusion constants and lengths, but their applicability to amorphous polymer systems must be evaluated. In this paper, the perylenediimide dye Lumogen Red in a poly(methyl methacrylate) host matrix is used to test theories of exciton motion over Lumogen Red concentrations (C(LR)'s) ranging from 1 x 10(-4) to 5 x 10(-2) M. Two experimental quantities are measured. First, time-resolved anisotropy decays in films containing only Lumogen Red provide an estimate of the initial energy transfer rate from the photoexcited molecule. Second, the Lumogen Red lifetime decays in mixed systems where the dyes Malachite Green and Rhodamine 700 act as energy acceptors are measured to estimate the diffusive quenching of the exciton. From the anisotropy measurements, it is found that theory accurately predicts both the C(LR)(-2) concentration dependence of the polarization decay time tau(pol), as well as its magnitude to within 30%. The theory also predicts that the diffusive quenching rate is proportional to C(LR)(alpha), where alpha ranges between 1.00 and 1.33. Experimentally, it is found that alpha = 1.1 +/- 0.2 when Malachite Green is used as an acceptor, and alpha = 1.2 +/- 0.2 when Rhodamine 700 is the acceptor. On the basis of the theory that correctly describes the anisotropy data, the exciton diffusion constant is projected to be 4-9 nm(2)/ns. By use of several different analysis methods for the quenching data, the experimental diffusion constant is found to be in the range of 0.32-1.20 nm(2)/ns. Thus the theory successfully describes the early time anisotropy data but fails to quantitatively describe the quenching experiments which are sensitive to motion on longer time scales. The data are consistent with the idea that orientational and energetic disorder leads to a time-dependent exciton migration rate, suggesting that simple diffusion models cannot accurately describe exciton motion within this system.
PMID: 20170138
ISSN: 1520-5215
CID: 4500942
Incipient corneoscleral xanthogranuloma with S-100 positivity in a teenager [Case Report]
Kanoff, Justin M; Colby, Kathryn; Jakobiec, Frederick A
PURPOSE/OBJECTIVE:To present a case of a corneoscleral juvenile xanthogranuloma (JXG) with diagnostically challenging features. METHODS:A 15-year-old boy's small corneoscleral mass of recent onset was examined histologically and immunohistochemically. RESULTS:The biopsy had some superficially misleading histological and immunohistochemical features: S-100 positivity (however, observable in 30% of JXG lesions) and lack of Touton giant cells (often absent in early lesions). Most importantly, the histiocytes stained negatively for CD1a and strongly positively for both lysozyme and CD68 antigen. CONCLUSIONS:JXG is a benign histiocytic disorder that usually appears early in childhood but is also encountered in 13%-18% of cases in the second decade. The histiocytes usually stain positively for CD68 and negatively for S-100 and CD1a. Correctly distinguishing JXG from the more aggressive spectrum of Langerhans cell diseases (100% have CD1a positivity) is essential for patient treatment.
PMID: 20458239
ISSN: 1536-4798
CID: 4500952
Keratoprosthesis: procedure of choice for corneal opacities in children? [Case Report]
Nallasamy, Sudha; Colby, Kathryn
PURPOSE/OBJECTIVE:The purpose of this study is to review the current literature on keratoprosthesis and its use in the pediatric population. METHODS:Case report and review of recent literature on outcomes of pediatric keratoplasty and keratoprosthesis. RESULTS:Penetrating keratoplasty in children is fraught with shortcomings, including difficulty maintaining a clear graft (as low as 44% at 50 months), poor visual acuity outcomes (only 30-34% achieving 20/400 or better), and a high rate of allograft rejection (40-50%). Placement of the Boston type I keratoprosthesis has the advantage of achieving a clear visual axis and stable refractive error within days of surgery without risk of rejection. However, life-long care is required, including topical steroids and antibiotic prophylaxis, as well as bandage contact lens wear and a frequent a need for further interventions for retroprosthetic membranes and glaucoma. CONCLUSIONS:With motivated parents, a successful anatomic and functional outcome can be achieved with the Boston keratoprosthesis in children of amblyogenic age.
PMID: 21091007
ISSN: 1744-5205
CID: 4501032
Corneal cross linking for keratoconus
Keating, Anne; Pineda, Roberto; Colby, Kathryn
Riboflavin-induced ultraviolet light (UV) cross linking has received a significant amount of attention in recent years. It is currently approved in Europe as a treatment for keratoconus and is also being used for other corneal disorders. The goal of this paper is to review in detail seminal papers and studies that have been done to support cross linking as a safe and effective treatment for patients with early stages of keratoconus.
PMID: 21091008
ISSN: 1744-5205
CID: 4501042
The clinical experience of Acanthamoeba keratitis at a tertiary care eye hospital
Tanhehco, Tasha; Colby, Kathryn
PURPOSE/OBJECTIVE:In recent years, outbreaks of Acanthamoeba keratitis (AK) have been reported worldwide. The purpose of this study was to examine the clinical experience of AK at the Massachusetts Eye and Ear Infirmary. METHODS:A retrospective case review was completed on patients with infectious keratitis whose corneal cultures were positive for Acanthamoeba between January 2000 and December 2008. The clinical characteristics and visual outcomes were examined in those patients with a follow-up period greater than 6 months. RESULTS:Four cases were identified between January 2000 and December 2003, whereas 26 cases were identified between January 2004 and December 2008. Charts before 2004 were unavailable for review. A total of 15 cases between 2004 and 2008 had a follow-up period of greater than 6 months. In these cases, possible risk factors associated with AK included soft contact lens wear (12 of 15 cases), exposure to freshwater or saltwater sources (8 of 15 cases), chronic ocular surface disease (6 of 15 cases), ocular trauma (3 of 15 cases), and concomitant infectious keratitis (2 of 15 cases). Four cases were associated with the use of Advanced Medical Optics Complete MoisturePlus Multi-Purpose Solution. Many cases were recalcitrant to medical therapy alone, necessitating therapeutic penetrating keratoplasty in 8 of 15 cases. CONCLUSIONS:The number of AK cases at the Massachusetts Eye and Ear Infirmary has increased since 2004. Contact lens wear and exposure to contaminated water sources were potential risk factors for AK. Clinicians should maintain a high clinical suspicion for AK in cases of atypical keratitis with known risk factors for AK.
PMID: 20539211
ISSN: 1536-4798
CID: 4500972
Pigmented deposits on a Boston keratoprosthesis from topical ibopamine [Case Report]
Kanoff, Justin M; Colby, Kathryn
PURPOSE/OBJECTIVE:To report a case of pigmented deposits on a type I Boston keratoprosthesis (KPro) associated with the use of topical ibopamine as a treatment for hypotony. METHODS:Case report and literature review. RESULTS:The dopamine-like agent ibopamine caused black deposits on the bandage lens and on the front plate of the Boston KPro that resulted in reduced visual acuity. Change to a daily disposable contact lens and regular cleaning of the KPro front plate with diluted baby shampoo eliminated this problem. CONCLUSION/CONCLUSIONS:This is the first report of this complication with topical ibopamine use and should be considered when ibopamine is used chronically for hypotony.
PMID: 20567201
ISSN: 1536-4798
CID: 4500982
Trends in fungal keratitis in the United States, 2001 to 2007
Gower, Emily W; Keay, Lisa J; Oechsler, Rafael A; Iovieno, Alfonso; Alfonso, Eduardo C; Jones, Dan B; Colby, Kathryn; Tuli, Sonal S; Patel, Seema R; Lee, Salena M; Irvine, John; Stulting, R Doyle; Mauger, Thomas F; Schein, Oliver D
OBJECTIVE:Fungal keratitis is a serious ocular infection that is considered to be rare among contact lens wearers. The recent Fusarium keratitis outbreak raised questions regarding the background rate of Fusarium-related keratitis and other fungal keratitis in this population. DESIGN/METHODS:Retrospective, multicenter case series. PARTICIPANTS/METHODS:Six hundred ninety-five cases of fungal keratitis cases who presented to 1 of 10 tertiary medical centers from 2001 to 2007. METHODS:Ten tertiary care centers in the United States performed a retrospective review of culture-positive fungal keratitis cases at their centers between January 2001 and December 2007. Cases were identified using microbiology, pathology, and/or confocal microscopy records. Information was collected on contact lens status, method of diagnosis, and organism(s) identified. The quarterly number of cases by contact lens status was calculated and Poisson regression was used to evaluate presence of trends. The Johns Hopkins Medicine Institutional Review Board (IRB) and the IRBs at each participating center approved the research. MAIN OUTCOME MEASURES/METHODS:Quarterly number of fungal keratitis cases and fungal species. RESULTS:We identified 695 fungal keratitis cases; 283 involved the use of contact lenses. The quarterly number of Fusarium cases increased among contact lens wearers (CLWs) during the period that ReNu with MoistureLoc (Bausch & Lomb, Rochester, NY) was on the market, but returned to prior levels after withdrawal of the product from the market. The quarterly frequency of other filamentous fungi cases showed a statistically significant increase among CLWs comparing October 2004 through June 2006 with July 2006 through December 2007 with January 2001 through September 2004 (P < 0.0001). CONCLUSIONS:The quarterly number of Fusarium fungal keratitis cases among CLWs returned to pre-Renu with Moistureloc levels after removal of the product from the market. However, the number of other filamentous fungal keratitis cases, although small, seems to have increased among refractive CLWs. Reasons for these apparent increases are unclear.
PMID: 20591493
ISSN: 1549-4713
CID: 4500992