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991.
PURPOSE: To describe symmetry of response in fellow eyes of patients undergoing photorefractive keratectomy (PRK) for myopia, analyse the risk factors leading to asymmetry in response and to determine if delayed treatment of the second eye increases safety and predictability of PRK. METHODS: Retrospective review of case records of 133 patients who underwent bilateral myopic PRK and had a minimum follow up of 6 months in both eyes. RESULTS: Postoperative uncorrected visual acuity, spherical equivalent (SE) refraction within +/- 1 D of emmetropia, best-corrected visual acuity (BCVA) and corneal haze were not significantly different in fellow eyes of patients undergoing PRK for myopia. Of 87 eyes in group 1 (myopia < 6 D), 96.6% had uncorrected visual acuity > or = 6/12, 89.7% were within +/- 1 D of emmetropia, none lost > or = 1 line BCVA, and none had haze > or = grade 3. Similar results for 98 eyes in group II (myopia 6 to 9.9 D) were 75.6%, 55.1%, 2.0% and 2.0% respectively. For 81 eyes in group III (myopia > or = 10 D) the results were 42.7%, 33.3%, 8.6%, and 4.9% respectively. Among 84 patients with similar preoperative myopia in both eyes, 54 (64.3%) patients had a postoperative SE difference < or = 1 D in fellow eyes. Risk factors for asymmetric response among fellow eyes included increasing preoperative myopia (p < 0.001) and dissimilar treatment technique in the two eyes (p = 0.03). Corneal haze did not increase significantly after the third postoperative month. CONCLUSION: This study demonstrates that considerable symmetry of response exists in fellow eyes of patients undergoing myopic PRK. Early PRK in the fellow eye of patients with < 6 D myopia is safe and allows quick visual rehabilitation of the patient. In patients with myopia > or = 6 D, a 3-month interval before treating the second eye may improve the safety of the procedure.  相似文献   
992.
PURPOSE: To report the timing of retreatment and clinical outcomes in patients with a partial corneal flap during laser in-situ keratomileusis (LASIK), and to describe the causes of this complication. METHODS: Retrospective review of case records of four patients (4 eyes) who had a partial corneal flap during LASIK. RESULTS: The mean age of the four patients was 23 +/- 4.7 years, and mean preoperative spherical equivalent (SE) refraction was -9.1 +/- 3.1 D (range, -5.5 to -13 D). A 160 microns corneal flap was attempted during the initial treatment. Retreatment with a 180 microns corneal flap was performed at a mean of 5.1 +/- 1.6 weeks (range, 4 to 7.5 weeks) after the initial procedure. There were no intraoperative complications during retreatment. Post-LASIK mean SE refraction was -1.0 +/- 1.1 D (range, +0.38 to -2.0 D), after a mean follow up of 19 +/- 15.7 weeks (range, 7 to 42 weeks). Best spectacle-corrected visual acuity decreased in one eye from 6/5 to 6/6 and was maintained in the others. CONCLUSION: LASIK retreatment can be performed as early as one month after a partial flap, if the refraction is stable and a thicker corneal flap is created.  相似文献   
993.
Vasomotor rhinitis is a frustrating experience both for the consultant and for the patient. The purpose of vidian neurectomy is to destroy the secretomotor nerve supply to the nasal mucosa, the main indication being severe intractable non-atopic vasomotor rhinitis. A review of 208 cases which have undergone transnasal vidian neurectomy by diathermy coagulation in the last five years is presented. The operation has proved worthwhile, the patients remaining symptom-free in 92 per cent of cases (longest follow-up 5 years). There have been no complications.  相似文献   
994.
995.
Conjunctival intraepithelial neoplasia presenting as corneal ulcer   总被引:2,自引:0,他引:2  
PURPOSE: To report a case of conjunctival intraepithelial neoplasia presenting as corneal ulcer. METHOD: Case report of a 28-year-old man who presented with sudden onset of pain, redness, and watering in the right eye. Examination of right cornea revealed deep stromal infiltrate inferonasally. Adjacent to the infiltrate and straddling the inferonasal limbus, a reddish well-defined sessible lesion with prominent blood vessels was seen. After corneal scraping for microbiological evaluation, the patient was treated with frequent instillation of ciprofloxacin hydrochloride 0.3% eyedrops. RESULTS: Corneal scraping revealed no microorganisms. Infiltrate resolved promptly after excision of the lesion. Histopathologic evaluation of the excised lesion revealed conjunctival intraepithelial neoplasia. CONCLUSIONS: This case highlights the fact that conjunctival intraepithelial neoplasia at the limbus may present as corneal ulcer. This ulcer could have occurred secondary to a dellen formation and epithelial breakdown predisposing to a corneal ulcer.  相似文献   
996.
PURPOSE: To evaluate the role of probing in congenital nasolacrimal duct obstruction in children age 2 years and older and to establish factors predictive of the outcome.METHODS: The study was a single-center, prospective, interventional case series. Sixty patients with congenital nasolacrimal duct obstruction aged 24 months or older (range, 24 to 186 months; median, 33 months) presenting consecutively to the authors' institutional referral practice were studied. Probing of the nasolacrimal system under general anesthesia was the surgical intervention. Success of probing was the main outcome measure. Success was predefined as complete resolution of symptoms and signs (tearing, crusting, discharge, regurgitation on pressure over the lacrimal sac) of congenital nasolacrimal duct obstruction within 3 weeks of the procedure and continued remission at 6 months. Two attempts at probing were necessary before the procedure was declared a failure.RESULTS: One attempt at probing resulted in resolution in 73.3% (44 of 60) patients. Sixteen patients needed a repeat procedure. The overall success rate was 80% (48 of 60). Two specific types of obstructions of the nasolacrimal duct were recognized on probing: membranous and firm. Factors predictive of failure of probing were age older than 36 months (P <.0001); bilateral affection (P =.012); failed conservative therapy (P =.015); failed earlier probing (P <.0001); dilated lacrimal sac (P <.0001); and firm obstruction (P <.0001). CONCLUSION: Results indicate that probing is a viable primary surgical option for congenital nasolacrimal duct obstruction in children who present between 2 and 3 years of age, and identify factors predictive of poor prognosis.  相似文献   
997.
Interference in the measurement of CA-125 in peritoneal fluid   总被引:1,自引:0,他引:1  
CA-125 has been found to be mildly elevated in the serum of patients with advanced stages of endometriosis, but not with minimal endometriosis. Peritoneal fluid levels were measured in conjunction with serum levels in 12 consecutive patients with endometriosis and 12 consecutive normal controls. Apparent peritoneal fluid values were found to be 10-fold higher than serum levels, with no difference between the study groups (130 versus 106 U/ml, respectively). However, when peritoneal fluid was diluted to validate the assay system in peritoneal fluid, no sample of peritoneal fluid showed decreased binding with serial dilutions of 1:2, 1:5, and 1:10. At a dilution of 1:100, there was some decreased binding, but the level was 17-fold higher than expected. The source of this interference is unknown.  相似文献   
998.
Peritoneal endometriotic implants and adjacent normal peritoneum from five patients were analyzed for prostaglandin (PG) release. Each tissue biopsy was incubated using medium 199 in triplicate at 37 degrees C for six hours, and PGF2 alpha and PGE2 concentrations were measured in the incubation medium every two hours. This study demonstrates that peritoneum involved with endometriosis releases significantly more PGF2 alpha and PGE2 (P less than .05) than adjacent normal peritoneum, and suggests that peritoneal endometriotic implants may be a source of the elevated peritoneal fluid PG levels previously reported in patients with endometriosis.  相似文献   
999.
AIM: To assess the prevalence of active and inactive uveitis unrelated to previous surgery or trauma in an urban population in southern India. METHODS: As part of the Andhra Pradesh Eye Disease Study, 2522 subjects (85.4% of those eligible), a sample representative of the population of Hyderabad city in southern India, underwent interview and detailed dilated eye examination. Presence of sequelae of uveitis without current active inflammation was defined as inactive uveitis. RESULTS: Unequivocal evidence of active or inactive uveitis unrelated to previous surgery or trauma was present in 21 subjects, an age-sex adjusted prevalence of 0.73% (95% confidence interval (CI) 0.44-1.14%). Active uveitis was present in eight subjects, an age-sex adjusted prevalence of 0.37% (95% CI 0. 19-0.70), of which 0.06% was anterior, 0.25% intermediate, and 0.06% posterior. The 0.36% (95% CI 0.17-0.68%) prevalence of inactive uveitis included macular chorioretinitis scars (0.26%), anterior (0. 07%) and previous vasculitis involving the whole eye (0.03%). The prevalence of visual impairment due to uveitis of less than 6/18 in at least one eye was 0.27%, less than 6/60 in at least one eye was 0. 16%, and less than 6/60 in both eyes was 0.03%. CONCLUSION: These population based cross sectional data give an estimate of the prevalence of various types of uveitis in this urban population in India. Active or past uveitis that might need treatment at some stage was present in one of every 140 people in this population.  相似文献   
1000.
AIM: To review the clinical characteristics, diagnosis, and visual outcome in patients with non-contact lens related Acanthamoeba keratitis and compare the findings with reported series of contact lens associated Acanthamoeba keratitis. METHODS: Medical and microbiology records of 39 consecutive patients with a diagnosis of Acanthamoeba keratitis, at a tertiary eyecare centre in India between January 1996 and June 1998, were analysed retrospectively. RESULTS: A majority of the patients presented with poor visual acuity and large corneal stromal infiltrates (mean size 38.20 (SD 26. 18) mm). A predisposing factor was elicited in 19/39 (48.7%) patients (trauma 15, dirty water splash three, leaf juice one). None of the patients had worn contact lenses. Most patients (26/39 (66. 6%)) came from a low socioeconomic background. Complaint of severe pain was not a significant feature and radial keratoneuritis was seen in 1/39 (2.5%) patients. A ring infiltrate was present in 41.1% of cases. A clinical diagnosis of fungal keratitis was made in 45% of the patients before they were seen by us. However, all patients were diagnosed microbiologically at our institute based on demonstration of Acanthamoeba cysts in corneal scrapings (34/39) and/or culture of Acanthamoeba (34/39). Treatment with biguanides (PHMB, 15/38 (39.4%), PHMB with CHx, 23/38 (60.5%), one patient did not return for treatment) resulted in healing with scar formation in 27 out of 31(87.0%) followed up patients (mean time to healing 106.9 days). Overall visual outcome was poor with no statistical difference between cases diagnosed within 30 days (early) or 30 days after (late) start of symptoms. The visual outcome in cases requiring tissue adhesive (five) and keratoplasty (three) was also poor. CONCLUSIONS: This is thought to be the largest series of cases of Acanthamoeba keratitis in non-contact lens wearers. In such cases, the disease is advanced at presentation in most patients, pathognomonic clinical features are often not seen, disease progression is rapid, and visual outcome is usually poor. Possible existence of Acanthamoeba pathotypes specifically associated with non-contact lens keratitis and unique to certain geographical areas is suggested.  相似文献   
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