Human corneal stromal tissue concentration after consecutive doses of topically applied 3.3% vancomycin.

AIMS: To evaluate vancomycin penetration into human corneal stromal tissue in patients treated with topical vancomycin eyedrops before penetrating keratoplasty (PKP). METHODS: Twenty four patients who underwent PKP, seven patients with keratoconus (group 1) and 17 patients with corneal scar or corneal decompensation (group 2). All patients received topical application of vancomycin eyedrops (concentration: 33 mg/ml) 10, 3, 2, 1 hour, and 15 minutes before the operation. Corneal cumulative vancomycin levels were assessed by bioassay. RESULTS: Mean vancomycin corneal stromal tissue concentration was 46.7 (SE 4.11) microg/g tissue. This value was four to 20-fold in excess of the MIC90 of vancomycin in Staphylococcus aureus (2-10 microg/ml). CONCLUSIONS: Vancomycin reached high corneal tissue concentrations that significantly exceeded the MIC90 (2-10 microg/ml) for most key Gram positive corneal pathogens. The ratio of vancomycin stromal concentration to protein concentration was statistically higher in group 2 (non-keratoconus).

Analysis of cell-free human alpha1 integrin with a monoclonal antibody to the I-domain: detection in ocular fluid and function as an adhesion substrate.

The alpha1 beta1 integrin, an inserted (1) domain containing collagen receptor, is expressed in the cell surface membrane of normal and malignant cells, and may play a role in their migration through tissues or in metastatic spread. Here we report that a functional anti-human alpha1beta1 integrin monoclonal antibody (mAb) (1B3.1) directly and specifically binds plastic bound recombinant human alpha1 I-domain protein containing the collagen binding site. Detection was diminished by acidification of the I-domain protein but was enhanced by increasing concentrations of Mg2+ cation. Furthermore, we detected binding of the mAb to proteins from the ocular fluids of 6 patients, with the highest concentration, corresponding to 22.1 ng/ml of I-domain, found in a sample from the eye of a patient with metastatic lung adenocarcinoma. Interestingly, we found that both SKNSH neuroblastoma cells and virally transformed human T cells adhered specifically to plastic wells coated with either immobilized collagen IV or alpha1 I-domain. MAb I B3.1 inhibited adhesion to collagen IV but not to immobilized I-domain. These results suggest a novel function for cell free alpha1 I-domain as a substrate for cellular adhesion, which may have relevance in tumor spread in vivo.

Postoperative endophthalmitis: incidence, predisposing surgery, clinical course and outcome.

OBJECTIVE: To describe the predisposing surgery, clinical course and final visual outcome for patients with culture-proven and culture-negative postoperative endophthalmitis. DESIGN: Case series. SETTING: University-affiliated teaching hospital in Toronto. PATIENTS: A total of 164 patients with clinically suspected postoperative endophthalmitis admitted between January 1989 and March 1996. OUTCOME MEASURES: Type of surgery, clinical presentation, culture results, infecting organism, treatment and final visual outcome. RESULTS: An infectious agent was identified in 99 cases (60%). The organism most commonly isolated was coagulase-negative Staphylococcus (59 cases [60%]). In the culture-proven group cataract extraction was the most common predisposing surgical procedure, accounting for 85 cases (extracapsular cataract extraction [ECCE] in 60 cases and phacoemulsification in 25). The incidence rates of culture-proven endophthalmitis over the study period at our institution were 0.22% for ECCE and 0.30% for phacoemulsification. Of the 99 patients with culture-proven endophthalmitis 94 received intravitreal injections of antibiotics and 52 underwent vitrectomy. Of the 83 patients in this group for whom the final outcome was known, 29 (35%) had a visual acuity of 20/50 or better, and 15 (18%) had a vision of no light perception, with four eyes undergoing enucleation. Infection with organisms of low virulence (coagulase-negative Staphylococcus or Propionibacterium acnes) was associated with higher rates of 20/50 or better visual acuity compared with more virulent organisms (Staphylococcus aureus, streptococcal species and gram-negative bacilli) (46% vs. 10%) (p < 0.05). The culture-negative group had a significantly lower frequency of hypopyon on presentation (55% vs. 85%) and final outcome of no light perception (2% vs. 18%) (p < 0.01) than the culture-proven group. CONCLUSIONS: Endophthalmitis was most common after cataract surgery. The rates of endophthalmitis after ECCE and phacoemulsification were similar. Postoperative endophthalmitis caused by organisms other than coagulase-negative Staphylococcus or P. acnes carries a poor visual outcome.

Preventing expulsive hemorrhage using an anterior chamber maintainer to eliminate hypotony.

We describe a method in which constant infusion inflow through an anterior chamber maintainer (ACM) is used to maintain positive intraocular pressure (IOP) during cataract extraction through a self-sealing tunnel incision. A retrospective review of patient records showed that the difference in the incidence of intraoperative suprachoroidal hemorrhage was significantly greater in eyes in which IOP was not constant throughout surgery than in eyes in which IOP was maintained using the ACM system.

Predicted and actual refraction after intraocular lens implantation in eyes with silicone oil.

OBJECTIVE: To determine the difference between the predicted and postoperative refraction in eyes with silicone oil that had extracapsular cataract extraction (ECCE), and intraocular lens (IOL) implantation. SETTING: Ophthalmology department providing primary, secondary, and tertiary care in central Israel. METHODS: Eight patients with silicone-oil-filled eyes following vitreoretinal procedures had ECCE and IOL implantation. The IOL power calculation was performed with the modified SRK II, the SRK/T, and the Holladay emmetropia/ametropia formulas, using the axial length of the eye, measured prior to the silicone oil injection, and the keratometric readings. The predicted and postoperative refractions were compared. RESULTS: The postoperative refraction was more hyperopic than predicted by an average of 4.08 diopters (D) for the SRK II formula, 3.91 D for the SRK/T formula, and 4.01 D for the Holladay emmetropia/ametropia formula. Removing the silicone oil from two eyes several months after cataract extraction reduced the deviation from the predicted refraction to 0.25 and 0.80 D. CONCLUSION: The presence of silicone oil in the vitreous space induces a hyperopic shift in eyes having ECCE and IOL implantation. This hyperopic shift should be considered when calculating the IOL power if a long-term tamponade with the oil is planned. If the silicone oil is to be removed shortly after the cataract extraction, the IOL power should be calculated solely from the formula.

Drug induced myopia associated with treatment for gynecological problems.

We present three cases of women who developed acute transient myopia caused by drugs for gynecological problems. One patient was treated with disothiazide for premenstrual edema. The second had acute cystitis and was treated by sulphonamide and the third developed myopia coincident with metronidazole treatment for trichomonas vaginalis. We followed these patients by A scan ultrasonographic ocular measurements, documenting reduction of the anterior chamber depth combined with lens thickening. The ocular and myopic changes cleared up completely on discontinuation of the causative agent. The possible mechanism is thought to be an allergic reaction to the drug.

[Ocular metastatic carcinoma--rare or common?].

Ocular metastatic carcinoma is the most common malignant neoplasm of the eye. It usually occurs after diagnosis of the primary tumor and the appearance of metastatic disease. However, it may be the initial manifestation of disease. Subclinical disease is often unnoticed because patients usually have metastatic disease to other organs which dominate the clinical picture. Regardless of the primary tumor, the prognosis following metastasis to the eye or orbit is poor, with average survival only a few months. The most common part of the eye involved by metastases is the highly vascular choroid, followed by the anterior segment, other orbital structures, lids, and retina. Early diagnosis and local treatment of the lesion maximize quality of life, but do not increase survival time.

Ischaemic heart disease risk factors in young black Africans from urban Zaire.

Blood pressure, pulse and body mass index were measured in 64 healthy black men, aged 20-44 years, from an urban region in Zaire. A required blood test for AIDS was extended to include plasma renin activity (PRA), total cholesterol (TC), triglycerides (TG) and high density lipoprotein cholesterol (HDL-C). Mean BMI was 21.99. Mean BP was 132.2/85.3 mmHg and hypertension (> 160/95 mmHg) was found in 17.2% of subjects. Very low PRA was found in 28 subjects and high PRA in one normotensive man. Mean PRA was 1.3 +/- 1.2. Mean plasma TC, TG and HDL-C were 136, 84, and 46 mg/dl, respectively, and mean TC/HDL-C ratio was 3:1. The frequency of hypertension in this study population is higher than that previously described for a different segment of the same population. It is, however, offset by a more favourable lipid profile that determines a more favourable overall cardiovascular risk profile.

Suggested mechanism for acute transient myopia after sulfonamide treatment.

This report describes the occurrence of acute transient myopia in a patient treated with sulfonamide. We followed this patient by performing A-scan ultrasonographic ocular measurements documenting the anterior chamber depth, lens thickness, and axial length during the acute and convalescent periods. The outstanding feature in this case was the documented ultrasonographically significant reduction of the anterior chamber depth combined with lens thickening. This could be caused by a forward displacement of the lens as a result of allergic ciliary body edema and rotation. These changes could explain the mechanism of drug-induced transient myopia.