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Yeong-Fong Chen

Publications and source records attributed to Yeong-Fong Chen.

12 recordsLinked to original sources
PubMed2006

Central corneal iron deposition after myopic laser-assisted in situ keratomileusis.

PURPOSE: To describe central corneal iron deposition after myopic laser-assisted in situ keratomileusis (LASIK). METHODS: Patients visiting our outpatient clinics between February 2003 and January 2004 and displaying post-LASIK corneal iron deposits were retrospectively enrolled in the study. RESULTS: Forty-two eyes of 24 patients developed corneal iron deposition after myopic LASIK surgery. All eyes displayed a small, spotty iron deposit located in the center of the corneal flap. The median interval between LASIK and diagnosis of corneal iron deposition was 22.5 months. The spherical equivalents of achieved correction ranged from 4.00 D to 17.50 D. CONCLUSION: Spotty corneal iron deposition can develop in the center of the corneal flap after myopic LASIK surgery. Because it is asymptomatic, the condition may have been hitherto underestimated in patient populations.

Adult↗
PubMed2006

Camphor-related self-inflicted keratoconjunctivitis complicating delusions of parasitosis.

PURPOSE: To report a case of camphor-related self-inflicted keratoconjunctivitis secondary to delusions of parasitosis. METHODS: A 61-year-old man with delusions of parasitosis suffered from camphor-related self-inflicted ocular trauma that manifested with corneal epithelial defects and secondary anterior chamber reaction. Two episodes of exacerbation of the ocular conditions related to the use of camphor occurred. The left eye had secondary infection with Sternotrophomonas maltophilia and Staphylococcus aureus in the second episode of exacerbation. RESULTS: The right eye recovered well with the treatment of topical lubricants and corticosteroids and had best-corrected visual acuity (BCVA) of 20/25. The infection of the left eye led to corneal perforation, necessitating penetrating keratoplasty; BCVA was hand motions because of a mature cataract. Olanzapine therapy for 1 month to decrease the delusions of parasitosis and 24-hour watch to prevent the use of camphor led to the resolution of self-inflicted keratoconjunctivitis in the patient. CONCLUSIONS: Delusions of parasitosis may lead to vision-threatening self-inflicted ocular trauma. This may be the first case report of pure camphor-related self-inflicted toxic keratoconjunctivitis.

Anterior Chamber↗
PubMed2006

Multiphoton fluorescence and second harmonic generation imaging of the structural alterations in keratoconus ex vivo.

PURPOSE: To demonstrate the application of multiphoton fluorescence (MF) and second harmonic generation (SHG) microscopy for ex vivo characterization of the structural alterations of human corneas due to keratoconus. METHODS: Buttons of keratoconic corneas derived from penetrating keratoplasty were sent for structural analysis with a custom-built multiphoton microscope. Fluorescence detected within the cytoplasm and the SHG signal obtained from collagen were used to demonstrate the morphologic changes in the corneal specimens. RESULTS: The fluorescent epithelial cells around the apical area were elongated and were aligned parallel to the adjacent collagen fibers. Parallel and centripetal distribution patterns of stromal collagen bundles were demonstrated at different depths within the keratoconic corneas. CONCLUSIONS: MF and SHG microscopy provides three-dimensional structural analysis of keratoconus ex vivo. It may provide important morphologic information for the investigation of the pathogenesis of keratoconus and may have potential in a clinical setting as an in vivo diagnostic and monitoring system for advancing keratoconus.

Cornea↗
PubMed2005

Mycobacterium keratitis after laser in situ keratomileusis.

PURPOSE: We present a case of Mycobacterium keratitis after laser in situ keratomileusis (LASIK). METHOD: A retrospective case report. RESULTS: A 40-year-old woman developed Mycobacterium chelonae keratitis in the right eye 2 weeks after bilateral LASIK. The diagnosis was made by acid-fast staining of corneal scrapings on admission and confirmed by culture results 2 weeks later. Intensive treatment with topical amikacin (25 mg/mL) and ciprofloxacin and partial excision of the flap led to resolution of the infection after 2 months of therapy. In addition, topical methylprednisolone (1 mg/mL) was necessary to control inflammation and pain. No recurrence was found during the 1-year follow-up period. The final uncorrected and corrected visual acuity in the right eye was 20/25 and 20/20, respectively. CONCLUSION: Mycobacterium keratitis is a potentially vision-threatening complication after LASIK. Early recognition of the organisms and aggressive treatment if infection develops may improve the outcome. When surgery is indicated, partial flap amputation, which may help to resolve the infection and preserve better vision, may be considered.

Administration, Topical↗
PubMed2005

Recurrent Alcaligenes xylosoxidans keratitis.

PURPOSE: To describe a case of postkeratoplasty recurrent Alcaligenes xylosoxidans keratitis. METHODS: A 33-year-old man with a history of penetrating keratoplasty developed corneal infiltrate with intact epithelium and then was treated with broad-spectrum antibiotics. Corneal scraping was taken for microbiologic study. RESULTS: The culture result identified A. xylosoxidans, sensitive to piperacillin and ceftazidime. There were 3 recurrent episodes within 2 months after each apparent resolution achieved after the instillation of topical piperacillin (10 mg/mL). During the fourth attack, the lesion responded poorly to piperacillin and ceftazidime (25 mg/mL), so therapeutic penetrating keratoplasty was performed to eradicate the recalcitrant infection. CONCLUSIONS: A. xylosoxidans has probably been underreported as a cause of ocular infection. It does not respond to conventional antibiotic therapy and may be difficult to eradicate. Therapeutic penetrating keratoplasty might be necessary if medical treatment fails.

Abscess↗
PubMed2005

Infectious keratitis related to overnight orthokeratology.

PURPOSE: To report the microbial culture results, clinical course, and visual outcomes for infectious keratitis related to overnight orthokeratology. METHODS: The records of patients with infectious keratitis related to overnight orthokeratology who presented to a tertiary referral center from April 2000 to March 2003 were retrospectively reviewed. RESULTS: Twenty patients (21 eyes) were included; 1 patient had bilateral infections. The average age of the patients was 14 years. The average period between the time the patient started the overnight orthokeratology program and the onset of infectious keratitis was 23 months. Thirteen of the 21 eyes were culture positive. Organisms cultured were Pseudomonas aeruginosa (n = 9), coagulase-negative Staphylococcus species (n = 2), Serratia marcescens (n = 1), and Acathamoeba species (n = 1). All patients responded well to medical antimicrobial treatment. Final best spectacle-corrected visual acuity ranged from 20/20 to 20/100. CONCLUSIONS: Infectious keratitis is a potential complication of overnight orthokeratology that may cause significant visual impairment. Parents of children who consider overnight orthokeratology should evaluate the benefit of temporary myopia reduction and the risk of infection.

Acanthamoeba↗
PubMed2005

Stenotrophomonas maltophilia keratitis and scleritis.

BACKGROUND: Stenotrophomonas maltophilia is a seldom-reported pathogen in ocular infections. The report describes six cases of Stenotrophomonas maltophilia (S. maltophilia) keratitis and scleritis. To our knowledge, this is the foremost report of S. maltophilia scleritis. METHODS: Laboratory reports of patients diagnosed with S. maltophilia ocular infections were collected from the ophthalmic department of Chang-Gung memorial hospital from January 1, 2000, through December 31, 2003. On evaluation of risk factors, isolates, antibiotic sensitivities, and response to the treatment ensued. RESULTS: Of the 6 reported cases, 5 related bacterial keratitis and 2 scleritis. (One case reported S. maltophilia keratitis and secondary scleritis.) The primary risk factor in such cases is ocular surgery. The organism cultured was the single isolate in three cases (50%). The susceptibility test showed that 50%, 83%, and 100% of the isolates were sensitive to ceftazidime, a combination of trimethoprim and sulfamethoxazole, and ciprofloxacin respectively. DISCUSSION: Ocular surface compromise such as penetrating keratoplasty was a primary risk factor of S. maltophilia keratitis in our study. The results of isolates and the antibiotic sensitivities were different from previously published results. Our cases responded well to antibiotic therapy and antibiotic therapy combined with conjunctival autografting. One case of S. maltophilia keratitis and secondary scleritis had a poor prognosis, arguably associated with a co-infection of Mycobacteria chelonae.

Adult↗
PubMed2004

Pseudomonas aeruginosa corneal ulcer related to overnight orthokeratology.

BACKGROUND: Overnight orthokeratology was thought to be a safe and non-invasive alternative for low-grade myopia and astigmatism correction. We assessed histories, clinical courses, and visual outcomes of the patients with pseudomonal keratitis related to overnight orthokeratology. METHODS: The records of six patients with pseudomonal keratitis related to overnight orthokeratology were reviewed from January 2001 through December 2002. RESULTS: The average age of the patients was 13 years. The average period between the time that the patient started the overnight orthokeratology program and the onset of infectious keratitis was 17 months. All patients presented with painful red eyes. The area of the corneal ulcer was central in three, and paracentral in three eyes. The corneal infiltrate was small in one eye, and medium in five eyes. The corneal scrapings from these six patients revealed Pseudomonas aeruginosa. All patients responded well to topical antibiotic treatment. Two of six eyes had a final visual acuity within two lines of the pre-infection vision at the last follow-up. Four of the eyes examined lost their best-corrected visual acuity due to central corneal scar or irregular astigmatism. CONCLUSIONS: Overnight orthokeratology contact lens wear has the potential complication of pseudomonal keratitis and may cause significant visual impairment.

Adolescent↗
PubMed2004

Idiopathic subconjunctival abscess.

Subconjunctival abscess is a relatively rare cause of ocular infection. It is usually associated with predisposing factors such as previous trauma or surgery. We report a case of subconjunctival abscess in a 61-year-old woman with no known risk factors. The subconjunctival abscess resolved completely after surgical excision and treatment with topical ciprofloxacin. The final vision preserved 20/20.

Abscess↗
PubMed2004

Early predict the outcomes of refractive accommodative esotropia by initial presentations.

BACKGROUND: The differential diagnosis between fully and partially refractive accommodative esotropia (Ac-ET) depends on outcomes after intervention with refraction correction. Whether the differences exist in terms of initial clinical features between these two variants has not been fully explored. METHODS: Children between the ages of 6 months and 8 years with esotropia and spherical equivalent greater than +3.00 (D) were included in this study. After wearing diopters glasses for at least 2 years, children were classified according to the indexed criteria into the fully Ac-ET group (group A, N=28) partially Ac-ET (group or the B, N=17). Six clinical parameters, including age at onset, age at first visit, visual acuity, refractive error, angle of esodeviation, and presence or absence of inferior oblique overaction at initial presentation were compared between these two groups. RESULTS: The angle of esodeviation (31.4+/-11.6 PD vs. 42.6+/-12.6 PD, p = 0.004) was significantly different between the fully and partially Ac-ET groups, while refraction (+5.79+/-1.84 D vs. +4.79+/-1.40 D, p = 0.062) had borderline significance. On the contrary, the age at onset (2.35+/-1.74 yrs vs. 2.01+/-1.96 yrs, p=0.539), age at first visit (3.51+/-1.36 yrs vs. 3.01+/-1.70 yrs, p =0.285), inferior oblique overaction (32% vs. 47%, p =0.317), and visual acuity before (LogMAR: 0.40+/-0.25 vs. LogMAR: 0.34+/-0.25, p =0.544) and after treatment (LogMAR: 0.057+/-0.079 vs. LogMAR: 0.051+/-0.19, p = 0.088) were similar in the two groups. CONCLUSIONS: Children with a smaller angle of esodeviation and higher hyperopia were more likely belonging to fully Ac-ET, which can be treated with glasses without the need of surgical intervention. Early detection and early treatment of accommodative esotropia are needed to prevent strabismus and amblyopia.

Accommodation, Ocular↗