[Keratic precipitate morphology in various uveitic entities: a confocal scan study]

To characterize keratic precipitate [KP] morphology in different forms of uveitis. One hundred and twenty nine eyes of 93 patients with different forms of uveitis underwent confocal scan and the morphology of KPs were determined. Differences in KP morphologies among different uveitic groups were evaluated. Age ranged from 14 to 67 years [mean: 32.5 +/- 11.2] and 58 cases [62.36%] were female, 38.7% had bilateral uveitis. Almost all types of uveitis disclosed predominantly stippled and globular KPs. Dendritiform KPs were more common in infectious uveitis [P=0.053] and smooth-rounded KPs were significantly more common in non-infectious uveitis [P<0.001]. Dendritiform KPs were observed more commonly in nongranulomatous uveitis than granulomatous ones [P=0.005]. Smooth-rounded KPs were more common in chronic uveitis than acute forms [P<0.001]. The predominant morphology of KPs in Fuchs heterochromic iridocyclitis [FHIC] were dendritiform [80.0%] and infiltrating [78.0%]. The most commonly observed morphology 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%]. Morphologic features in bilateral cases were similar. KP morphologies are diverse in different forms of uveitis. Some forms of KPs are less specific such as globular and stippled which exist in almost all types of uveitis. Confocal scan can play a potential role in differentiating infectious from noninfectious uveitis and granulomatous from nongranulomatous uveitis

[ outbreak of nocardia keratitis following photorefractive keratectomy]

To report 3 cases of nocardia keratitis following photorefractive keratectomy [PRK]. Report of Outbreak: Four eyes of 3 patients [2 female and one male] who had undergone PRK by a single surgeon at a single center developed nocardia keartitis 3 to 6 weeks postoperatively. Mean age was 25 [range 23-28] years and mean onset of corneal manifestations was 29 [range 21-40] days after PRK. Corneal smear and culture and confocal scan were performed in all eyes. Two eyes from the first two patients required lamellar keratectomy to debulk the involved stroma and to obtain specimens for microbiologic and histopathologic evaluation. Light microscopic examination disclosed gram-positive and acid-fast filaments of nocardia which were confirmed by the microbiologic results. Diagnosis of nocardia keratitis in the third case was not as challenging as the first two cases because of a high index of suspicion. Confocal scan in all cases disclosed hyperreflective and slender fibril-like structures in the corneal stroma. All eyes responded favourably to topical amikacin and the infection resolved without recurrence. Nocardia is a rare cause of keratitis following PRK. Clinical suspicion along with microbiologic, histopathologic and confocal scanning help to establish the correct diagnosis. The most probable cause of the outbreak was inadequate attention to sterility during surgery

[Orbital echinococcosis with two different features; hydatid and alveolar cysts]

To present two patients with hydatid and alveolar cysts of the orbit and to present their clinical, imaging, pathologic and therapeutic features. Two young children from rural areas were referred for progressive proptosis. Imaging showed intraorbital cysts. They were operated on with a clinical suspicion of hydatid and alveolar cysts. Pathologic evaluation confirmed the diagnoses in both instances. Clinical findings and imaging before the operation help the diagnosis of orbital echinococcosis. Knowing the nature of these lesions can prevent surgical complications. Alveolar cysts are much more invasive than hydatid cysts and their treatment is more difficult

[Unusual neoplastic recurrence in the corneo-scleral limbus: recurrent atypical fibrous histiocytoma followed by intra-epithelial squamous neoplasia]

To report the clinical and histopathological features of recurrent atypical fibrous histiocytoma of the corneo-scleral limbus followed by intra-epithelial squamous neoplasia. A 25-year-old female patient presented with a recurrent vascularized gelatinous mass in the left nasal limbus. The preliminary histopathological diagnosis of the previously excised lesion was an amelanotic malignant melanoma at a private general pathology center. The lesion had recurred after one year and the histopathologic diagnosis was a poorly differentiated malignant melanoma at another pathology center. The lesion recurred again and the specimen was sent to a third histopathologic center where the histopathologic diagnosis revealed spindle cell growth with moderate atypia. A pannus-like lesion occurred in the nasal limbus 3 years later which was excised and sent to the Eye Bank Pathology Laboratory. Reviewing the slides related to the first recurrent lesion and the histopathologic examination of the recently excised specimen disclosed a final diagnosis of atypical fibrous histiocytoma and intra-epithelial squamous neoplasia, respectively. Fibrous histiocytoma is a rare limbal tumor that may have atypical features and can be misdiagnosed as an amelanotic melanoma. This is also a rare report on the occurrence of intraepithelial squamous neoplasia following excision of recurrent fibrous histiocytoma

[ Confocal Scan Features of Keratic Precipitates in Fuchs' Heterochromic Iridocyclitis]

To report confocal scan features of keratic precipitates [KPs] in Fuchs' heterochromic iridocyclitis [FHIC]. In this descriptive study, corneal confocal scan was performed to characterize KPs in patients with FHIC referred to Labbafinejad Medical Center from November 2005 to March 2007. Polymerase chain reaction [PCR] for Herpes Simplex virus, Herpes Zoster virus, Toxoplasma gondii, Cytomegalovirus and Rubella virus was performed on aqueous humor samples taken in 4 patients who underwent phacoemulsification. Confocal scan was performed in 40 eyes of 34 patients including 18 male and 16 female subjects with mean age of 30.7 +/- 10.5 [range 18-57] years. FHIC was bilateral in 6 and unilateral in 28 patients. The distribution of KPs was diffuse in 31 eyes and limited to the inferior cornea in 9 eyes. The morphology of KPs included: globular, 34 eyes [85%]; infiltrating, 31 eyes [77.5%]; dendritiform, 31 eyes [77.5%]; stippled, 27 eyes [67.5%]; and cruciform, 25 eyes [62.5%]. None of the cases demonstrated smooth-rounded KPs. PCR of aqueous specimens was negative for the above-mentioned infectious agents in 4 eyes who had infiltrating and dendritiform KPs on confocal scan. Confocal features of KPs in FHIC are diverse and include globular, infiltrating and dendritiform, stippled and cruciform. Presence of infiltrating and dendritfrom KPs in FHIC may be suggestive of a possible infectious etiology, however the results of PCR were negative in the limited numbers of such patients in our series