Intracorneal bacterial colonization in a crystalline pattern

We report the case of a 78-year-old woman who developed an intrastromal bacterial colonization 22 months after penetrating keratoplasty. Slit-lamp examination revealed discrete, finely branched, fernlike stromal opacities, which were histopathologically found to be large intrastromal aggregates of gram-positive cocci with almost no inflammatory cell response.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47391/1/417_2005_Article_BF02143065.pd

Corneal Sensitivity and Dry Eye Symptoms in Patients with Keratoconus.

PURPOSE: To investigate corneal sensitivity to selective mechanical, chemical, and thermal stimulation and to evaluate their relation to dry eye symptoms in patients with keratoconus. METHODS: Corneal sensitivity to mechanical, chemical, and thermal thresholds were determined using a gas esthesiometer in 19 patients with keratoconus (KC group) and in 20 age-matched healthy subjects (control group). Tear film dynamics was assessed by Schirmer I test and by the non-invasive tear film breakup time (NI-BUT). All eyes were examined with a rotating Scheimpflug camera to assess keratoconus severity. RESULTS: KC patients had significatly decreased tear secretion and significantly higher ocular surface disease index (OSDI) scores compared to controls (5.3+/-2.2 vs. 13.2+/-2.0 mm and 26.8+/-15.8 vs. 8.1+/-2.3; p0.05). The mean threshold for selective mechanical (KC: 139.2+/-25.8 vs. control: 109.1+/-24.0 ml/min), chemical (KC: 39.4+/-3.9 vs. control: 35.2+/-1.9%CO2), heat (KC: 0.91+/-0.32 vs. control: 0.54+/-0.26 Delta degrees C) and cold (KC: 1.28+/-0.27 vs. control: 0.98+/-0.25 Delta degrees C) stimulation in the KC patients were significantly higher than in the control subjects (p0.05), whereas in the control subjects both mechanical (r = 0.52, p = 0.02), chemical (r = 0.47, p = 0.04), heat (r = 0.26, p = 0.04) and cold threshold (r = 0.40, p = 0.03) increased with age. In the KC group, neither corneal thickness nor tear flow, NI-BUT or OSDI correlated significantly with mechanical, chemical, heat or cold thresholds (p>0.05 for all variables). CONCLUSIONS: Corneal sensitivity to different types of stimuli is decreased in patients with keratoconus independently of age and disease severity. The reduction of the sensory input from corneal nerves may contribute to the onset of unpleasant sensations in these patients and might lead to the impaired tear film dynamics

Detection of specific collagen types in normal and keratoconus corneas.

Keratoconus is a corneal disease of unknown cause that involves a progressive thinning and scarring of the corneal connective tissue. We examined normal human and keratoconus corneas, including one healed penetrating keratoplasty specimen. Organ cell cultures of normal and keratoconus corneal specimens were labeled with radioactive proline and analyzed by CM-cellulose chromatography and slab gel electrophoresis to determine collagen biosynthesis. Collagen types I and III were synthesized in similar amounts by normal and keratoconus stromacytes in culture. Specifically purified antibodies were used to determine the distribution of collagen types in tissue sections by immunofluorescence. The distribution of collagen types I, III, and IV in keratoconus was also similar to that in normal corneas, except that scarred regions in keratoconus and at the host-graft juncture were largely type III. Immunofluorescent reaction of the anti-type IV collagen antibodies with Bowman's layer, in particular, and Descemet's membrane in keratoconus specimens indicated extensive destruction. Basement membrane destruction may play an important role in this disease

Lamellar corneal autograft for corneal perforation

A corneal perforation developed in the right eye of a 46-year-old man after removal of a corneal foreign body. Two attempts to seal the perforation with cyanoacrylate glue failed. The patient subsequently underwent lamellar corneal autograft, which successfully closed the perforation. To the best of our knowledge, this is the first report of repairing a corneal perforation with lamellar corneal autograft

Elevated Corneal Epithelial Lines in Acanthamoeba Keratitis

• Elevated corneal epithelial lines are another clinical sign in Acanthamoeba corneal infection. In this report, one patient wore extended wear soft contact lenses, and another wore daily wear soft contact lenses. Both patients used distilled water and salt tablets in their lens care. Histopathologic examination of these lines revealed trophozoites and cysts. In one of the patients following penetrating keratoplasty, Acanthamoeba castellani and Acanthamoeba polyphaga were cultured by impression cytology of an epithelial line, as well as from the bulbar and tarsal conjunctiva. In the other patient who did not undergo penetrating keratoplasty, these lines appeared in the cornea one month after initial symptoms