Various confocal scan features of cysts and trophozoites in cases with Acanthamoeba keratitis.

PURPOSE: To describe the various confocal scan features of cysts and trophozoites in patients with Acanthamoeba keratitis and to specify the associated findings. METHODS: In a retrospective study of cases between June 2005 and June 2010, we reviewed all the recorded confocal scan images of patients given a high index in regards to clinical suspicion of Acanthamoeba keratitis, in order to specify the various morphometric and morphologic features of Acanthamoeba cysts and trophozoites and to characterize the associated findings in such cases. RESULTS: Confocal scan images of 170 eyes from 170 patients were reviewed. Bilayered, target-shaped, coffee-bean and rod-shaped appearances of the cysts were observed in 100%, 82.9%, 36.4%, and 17.5% of cases, respectively. Single file arrangement of the cysts was noticed in 22 cases. The mean size of the cysts was 18.9 µm (range 10-39.6). In all cases, trophozoites were observed as pear-shaped or irregularly wedge-shaped structures, some surrounded by a brilliant halo and some exhibiting fine pseudopodia-like extensions, with mean size of 30.2 µm (range 19.2-55.6). Keratoneuritis and the anterior stromal honeycomb pattern were seen in 28.2% and 5.9% of cases, respectively. CONCLUSIONS: To our knowledge, this is the largest case-series study on confocal scan features of Acanthamoeba cysts and trophozoites in cases with clinical diagnosis of Acanthamoeba keratitis specifying the morphologic and morphometric criteria of this infectious organism and the associated findings.

Confocal scan of keratic precipitates in uveitic eyes of various etiologies.

PURPOSE: To specify confocal scan features of keratic precipitates (KPs) in uveitic eyes of various etiologies. METHODS: Confocal scan was performed on 129 eyes of 93 patients with different types of uveitis to characterize the morphologic features of KPs. The study included Fuchs heterochromic iridocyclitis (FHIC) in 50 eyes, idiopathic granulomatous uveitis in 27, herpetic anterior uveitis in 10, pars planitis associated with endotheliitis in 9, Vogt-Koyanagi-Harada syndrome in 8, multiple sclerosis-related uveitis in 7, sarcoidosis in 3, acute anterior uveitis not associated with HLA B27 in 3, acute retinal necrosis in 2, psoriatic uveitis in 2, chronic endophthalmitis in 2, sclerouveitis in 2, HLA B27-associated anterior uveitis in 2, sympathetic ophthalmia in 1, and toxoplasmosis in 1. The differences in types of KPs between various uveitic groups were analyzed. RESULTS: Mean age of the patients was 32.5 +/- 11.2 (range, 14-67) years, and 58 (62.36%) were female. Bilateral involvement was observed in 36 cases (38.7%). Stippled and globular KPs were predominantly observed in almost all types of uveitis. With comparing the infectious versus noninfectious uveitis, dendritiform KPs were almost more common in infectious uveitis (P = 0.053) and smooth-rounded KPs were significantly more common in noninfectious uveitis (P = 0.000). Dendritiform KPs were observed more commonly in nongranulomatous uveitis than in the granulomatous ones (P = 0.005). Smooth-rounded KPs were more common in chronic uveitis than in the acute forms (P = 0.000). Predominant morphologies of KPs in FHIC were dendritiform (80.0%) and infiltrating (78.0%). The most commonly observed morphologies of KPs in intermediate uveitis were dendritiform (56.3%) and smooth rounded (56.3%). Cruciform KPs were more frequently seen in cases with FHIC (60.0%). In bilateral cases, the morphologic features were similar. CONCLUSIONS: Morphologic features of KPs in various types of uveitis are diverse. Stippled and globular KPs may be observed in almost all types of uveitis. Certain types of KPs are more frequently associated with specific forms of uveitis, that is, smooth-rounded KPs may be an indicative of a granulomatous uveitis and infiltrating and dendritiform in infectious uveitis. Confocal scan may play a potential important role in identification of underlying mechanisms in complex forms of uveitis.

Meesmann corneal dystrophy; a clinico-pathologic, ultrastructural and confocal scan report.

PURPOSE: To report the microstructural features of Meesmann corneal dystrophy (MCD) in two patients. CASE REPORT: The first patient was a 10-year-old boy who presented with bilateral visual loss, diffuse corneal epithelial microcystic changes, high myopia and amblyopia. With a clinical impression of MCD, automated lamellar therapeutic keratoplasty was performed in his left eye. Histopathologic examination of the corneal button disclosed epithelial cell swelling and cyst-like intracytoplasmic inclusions. The cells contained moderate amounts of periodic acid-Schiff-positive and diastase-sensitive material (glycogen). Transmission electron microscopy revealed numerous vacuoles and moderate numbers of electron-dense membrane-bound bodies in the cytoplasm, similar to lysosomes, some engulfed by the vacuoles. The second patient was a 17-year-old female with a clinical diagnosis of MCD and episodes of recurrent corneal erosion. On confocal scan examination of both corneas, hyporeflective round-shaped areas measuring 6.8 to 41.4 µm were seen within the superficial epithelium together with irregular and ill-defined high-contrast areas in the sub-basal epithelial region. The subepithelial nervous plexus was not visible due to regional hyperreflectivity. CONCLUSION: This case report further adds to the microstructural features of Meesmann corneal dystrophy and suggests confocal scan as a non-invasive method for delineating the microstructural appearance of this rare dystrophy.

Relapse of Acute Lymphoblastic Leukemia as a Conjunctival Mass in a 9-Year-Old Girl.

A 9-year-old girl with a history of acute lymphoblastic leukemia in remission presented with a right subconjunctival mass and ipsilateral preauricular lymphadenopathy despite normal findings on blood cell profile. Excisional biopsy of the lesion was performed to exclude extramedullary relapse of acute lymphoblastic leukemia. Histopathologic examination showed infiltration of leukemic cells at the conjunctival substantia propria. The patient was referred to her oncologist, and bone marrow aspiration showed medullary relapse of acute lymphoblastic leukemia for which systemic and intrathecal chemotherapy was administered. Leukemic infiltration of the conjunctiva in the presence of normal findings on blood cell profile can be a rare manifestation of relapsed acute lymphoblastic leukemia.

Outbreak of Nocardia keratitis after photorefractive keratectomy: clinical, microbiological, histopathological, and confocal scan study.

Nocardia keratitis occurred in 4 eyes of 3 patients (2 women and 1 man) who had photorefractive keratectomy (PRK) by the same surgeon at the same center. Two eyes of the first 2 patients required lamellar keratectomy to debulk the involved stroma and obtain specimens for microbiological and histopathological evaluation. Light microscopic examination disclosed gram-positive and acid-fast filaments of Nocardia that were confirmed by the microbiological results. Diagnosis of Nocardia keratitis in the third case was not as challenging as in the first 2 cases because of a high index of suspicion. Confocal scans of all cases disclosed hyperreflective and slender, fibril-like structures in the corneal stroma. All eyes responded favorably to topical amikacin and the infection resolved without recurrence. The most probable cause of the outbreak was inadequate attention to sterility during surgery.