Fungal ring infiltrates in disposable contact lens wearers.

PURPOSE: To report two cases of ring infiltrates in disposable contact lens wearers resembling Acanthamoeba keratitis but later identified as fungus. METHODS: We report two patients with histories of disposable soft contact lens use, who, on initial presentation, were found to have corneal ring infiltrates and were treated for presumed Acanthamoeba keratitis. Microbiological studies, which included Gram stain and Gomori methenamine silver stain, as well as blood agar, chocolate agar, thioglycolate broth, Sabouraud agar, nonnutrient agar with Escherichia coli overlay, and Lowenstein-Jensen plates, were performed. RESULTS: Microbiological studies revealed fungi in both cases. CONCLUSIONS: Fungal keratitis is an uncommon complication of disposable soft contact lens use, but it should be considered in the differential diagnosis of corneal ring infiltrates.

Fungal keratitis in a daily disposable soft contact lens wearer.

PURPOSE: To report the first case of fungal keratitis in a patient wearing daily disposable soft contact lenses. METHODS: Case Report. A 20-year-old white female in good health developed a corneal ulcer in her lefteye associated with daily disposable soft contact lens wear. There was no history of trauma to the left eye, and she denied overnight wear. Corneal scrapings were taken, and the patient was started on intensive tobramycin 14 mg/mL and cefazolin 50 mg/mL topical therapy for suspected bacterial keratitis. After 3 days of antibacterial therapy, the ulcer worsened. The cultures were negative as were the Gram stain and Gomori's methenamine silver stain. Initial cultures and stains were then repeated with the addition of a culture for herpes simplex virus. The developing clinical picture was suspicious for fungal keratitis. The patient was then started on intensive vancomycin 2%, natamycin 5%, and continued on fortified tobramycin. Three days after the second corneal scrapings were performed, a positive fungal culture was obtained for Fusarium sp. Vancomycin and tobramycin were then discontinued and amphotericin B 0.15% was added to natamycin 5% with the continuation of intensive topical therapy. RESULTS: The patient's keratitis was successfully treated with intensive double antifungal therapy. CONCLUSIONS: Infectious keratitis in daily disposable soft contact lens wear is an unusual occurrence. To our knowledge, there is no previous case of fungal keratitis occurring in patients wearing daily disposable lenses. This case emphasizes the importance of considering fungus in the differential diagnosis for keratitis even in daily disposable contact lens wearers.

Facial nerve injury following superficial temporal artery biopsy.

BACKGROUND: With proper training, superficial temporal artery biopsy is a safe office procedure with few complications. Surgeons from different disciplines, including ophthalmologists, dermatologists, general surgeons, and plastic surgeons may be called upon to perform this common procedure to confirm giant cell arteritis. OBJECTIVE: To emphasize the surgical anatomy of the scalp as it pertains to superficial temporal artery biopsy and to raise awareness that significant complications can occur after superficial temporal artery biopsy. METHOD: Case report. RESULTS: A 75-year-old woman with presumed giant cell arteritis developed frontalis muscle paralysis following a superficial temporal artery biopsy. Biopsy selection site within the danger zone combined with deep dissection carries the greatest risk of injury to the temporal branches of the facial nerve. CONCLUSION: Any surgeon involved in the practice of performing superficial temporal artery biopsies should have a thorough understanding of proper surgical techniques and regional anatomy to avoid potential devastating complications.

Diagnosis of hemophilia made after intraoperative bleeding during attempted penetrating keratoplasty in an elderly patient.

PURPOSE: To report an unusual case where the diagnosis of hemophilia was made after attempted penetrating keratoplasty in an elderly patient. METHODS: A 75 year old white male with a full-thickness corneal scar in the visual axis and a visually significant cataract OD was to undergo penetrating keratoplasty and cataract extraction with lens implantation for visual rehabilitation. There was no history of bleeding diathesis given. RESULTS: During placement of the Flieringa ring, a progressively enlarging 360 degrees subconjunctival hemorrhage was observed. Given the unusual bleeding,the procedure was aborted and the patientwas referred to the hematology service for further evaluation. Laboratory studies revealed a diagnosis of atypical hemophilia of mild severity. CONCLUSIONS: The initial diagnosis of hemophilia in any elderly patient is unusual. This case is even more unusual asthe diagnosis of a bleeding disorder was first considered after excessive subconjunctival hemorrhage developed during attempted penetrating keratoplasty.

Fungal keratitis after laser in situ keratomileusis: a case report.

PURPOSE: To report a case of fungal keratitis resulting after laser in situ keratomileusis (LASIK). METHODS: A 38-year-old white man in good health developed a corneal infiltrate with laboratory confirmation of fungal keratitis after LASIK. Corneal scrapings were taken. Silver stain was positive for hyphae. Culture was positive for Curvularia sp. The patient was started on intensive natamycin 5% and amphotericin 0.15% topical therapy. RESULTS: The patient's keratitis was successfully treated with intensive antifungal therapy. CONCLUSIONS: Infectious keratitis is a rare but a serious potential complication after LASIK. To our knowledge, no previous case of fungal keratitis after LASIK has been reported. This case emphasizes the importance of surveillance for infection after LASIK.

Mycobacterium chelonae keratitis after laser in situ keratomileusis successfully treated with medical therapy and flap removal.

PURPOSE: To report a case of Mycobacterium chelonae keratitis after laser in situ keratomileusis successfully treated with medical therapy and flap removal. METHODS: Case report. A 36-year-old white woman in good health developed a paracentral keratitis in her right eye 1 month after bilateral laser in situ keratomileusis. Initial treatment included topical steroids and then intensive Ocuflox (ofloxacin ophthalmic solution; Allergan, Inc, Irvine, California) without success. Cultures were negative. The keratitis worsened, and she was referred to our institution. Interface infiltration was noted, and the flap was lifted to obtain adequate laboratory studies. Cultures were positive for M chelonae. RESULTS: The keratitis was treated with intensive topical amikacin sulfate 1%, topical clarithromycin 1%, and Ciloxan (ciprofloxacin HCL; Alcon Laboratories, Inc, Fort Worth, Texas) with minimal improvement in her clinical condition. She developed a toxic reaction to amikacin 1%. In order to improve antibiotic penetration, the hazy, ulcerated corneal flap was removed. The keratitis then resolved with intensive topical clarithromycin 1% and Ocuflox over 5 weeks. The patient now has visual acuity without correction of 20/50, despite superficial corneal haze. CONCLUSION: M chelonae is a rare and insidious cause of infection after laser in situ keratomileusis. Diagnosis can be difficult and is often delayed. Aggressive medical management, with flap removal, if needed, may lead to resolution of infection.

Emerging fluoroquinolone resistance in bacterial keratitis: a 5-year review.

OBJECTIVE: To identify resistance patterns to the fluoroquinolones for patients with bacterial keratitis. DESIGN: Retrospective observational case series. PARTICIPANTS: All cases of bacterial keratitis presenting to the Charles T. Campbell Ophthalmic Microbiology Laboratory at the Eye and Ear Institute of Pittsburgh from January 1993 to December 1997 were reviewed. A total of 1053 ocular isolates from 825 cases of bacterial keratitis were identified. MAIN OUTCOME MEASURES: In vitro laboratory susceptibility testing of ocular isolates to ciprofloxacin and ofloxacin was determined by the Kirby-Bauer disk diffusion method and interpreted using the National Committee for Clinical Laboratory Standards serum standards. RESULTS: The number of cases of bacterial keratitis per year decreased from 284 in 1993 to 75 in 1997. The ratio of gram-positive to gram-negative organisms changed from 81.8%:18.2% in 1993 to 51.4%:48.6% in 1997 (chi-square, 66.00; degrees of freedom, 4; P < 0.000001). Resistance of Staphylococcus aureus to ciprofloxacin significantly increased annually from 5.8% in 1993 to 35.0% in 1997 (chi-square, 19.80; degrees of freedom, 4; P < 0.0001) and for ofloxacin from 4.7% to 35.0% over the same period (chi-square, 21.32; degrees of freedom, 4; P < 0.001). Streptococcus species and coagulase-negative Staphylococcus species showed significant resistance to both fluoroquinolones but no change in resistance over the study period. The gram-negative organisms showed good susceptibility to the fluoroquinolones. CONCLUSIONS: This in vitro study shows a significant increased resistance of S. aureus to the fluoroquinolones from 1993 to 1997. In addition, gaps in fluoroquinolone coverage for Streptococcus and coagulase-negative Staphylococcus species raise concern for the use of monotherapy in treating bacterial keratitis. Contrary to what might be expected, the distribution of gram-positive to gram-negative organisms has shifted, with a decrease in the number of gram-positive organisms identified, while the number of gram-negative isolates has remained stable.

Consistent responses of human mothers to prelinguistic infants: the effect of prelinguistic repertoire size.

The salience of infants' vocal and visual cues was examined to evaluate the efficacy of prelinguistic vocalizations to guide adult behavior. A videotape, constructed of brief behavioral episodes from 3 infants with different-sized vocal repertoires, was played to 40 mothers of prelinguistic infants. Playback mothers' responses to the episodes were consistent, demonstrating that preverbal behavior elicits comparable reactions across unfamiliar receivers. The audio and video components of the infants' episodes were then recombined. As the vocal repertoire of the stimulus infants increased, changes in the audio component more often led playback mothers to change responses. Thus, playback mothers used vocalizations as cues as the infants' vocal repertoires became larger.

Conjunctival cysts of the orbit.

OBJECTIVE: This study reviews functionally and anatomically disruptive features of simple conjunctival orbital cysts. DESIGN: A case series review from four oculoplastic practices over 6 years. PARTICIPANTS: Eleven patients with simple conjunctival cysts of the orbit were identified. INTERVENTION: All cysts were excised and evaluated histopathologically. MAIN OUTCOME MEASURES: Assessment was made of the length of time from inciting event to presentation, preoperative and postoperative refractive state and ocular motility, the presence or absence of discomfort, and radiographic or clinical evidence of bone remodeling. RESULTS: Six of 11 cysts were presumed to be primary, unrelated to antecedent surgery or trauma. Four of 11 cysts were associated with pain or tenderness, 5 cysts induced ocular motility disturbance, 6 cysts caused observable globe distortion or refractive error change, and 6 cysts remodeled bone. CONCLUSIONS: Simple conjunctival cysts of the orbit, traditionally regarded as low-pressure lesions with minimal structural impact, may induce considerable anatomic and functional disruption.

Comparison of mitomycin C trabeculectomy, glaucoma drainage device implantation, and laser neodymium:YAG cyclophotocoagulation in the management of intractable glaucoma after penetrating keratoplasty.

PURPOSE: This study aimed to compare the surgical outcomes of mitomycin C trabeculectomy glaucoma drainage device (GDD) surgery and laser neodymium:YAG (Nd:YAG) cyclophotocoagulation (CPC) in the management of intractable glaucoma after penetrating keratoplasty (PKP) in a retrospective study. DESIGN: Interventional case series. PARTICIPANTS/METHODS: The medical charts of consecutive patients who had pre-existing glaucoma or who developed glaucoma after PKP and underwent a surgical procedure to control the glaucoma at the University Eye Associates of Boston University Medical Center, New England Eye Center, and Massachusetts Eye and Ear Infirmary between January 1991 and July 1995 were reviewed. Follow-up ranged from 6 months to 4 years after the glaucoma procedure. A total of 38 patients were included consisting of 17 patients who underwent mitomycin C, 10 patients who underwent GDD surgery, and 11 patients who had CPC. INTERVENTION: Mitomycin C trabeculectomy, GDDs, or Nd:YAG CPC to control glaucoma after PKP was performed, MAIN OUTCOME MEASURES: Graft status, postoperative intraocular pressure (IOP), and visual acuity were the main outcome measures. RESULTS: There were no differences among the three groups with respect to the follow-up time after the corneal graft operation (P = 0.15) or after the glaucoma operation (P = 0.98). At the final follow-up, the average decrease in the IOP was 17 mmHg (P < 0.001) after mitomycin C, 15 mmHg (P = 0.003) after GDD surgery, and 14.4 mmHg (P = 0.001) after CPC. There were no differences in the proportion of patients who developed postoperative IOP above 20 mmHg (P = 0.50) and in the proportion who developed hypotony (P = 0.10) among the three groups. Two grafts failed after mitomycin C and one failed after CPC. Among the three procedures, there were no differences in the proportion of patients who experienced either an improvement (P = 0.14) or a decrease (P = 0.22) in the visual acuity by more than one line after the glaucoma procedure. One patient each in the GDD group and the CPC group lost light perception after the procedure. The risk of graft failure was almost three times higher for each additional PKP (odds ratio = 2.80, P = 0.02). CONCLUSIONS: No differences were found among the three glaucoma procedures with respect to controlling IOP and graft failure. There was a trend for patients treated with CPC to have a higher incidence of graft failure, glaucoma failure, hypotony, and visual loss by more than one line, although this was not statistically significant. The number of PKPs was associated with graft failure, independent of the surgical procedure.

Neuroperceptual differences in consonant and vowel discrimination: as revealed by direct cortical electrical interference.

The effects of direct cortical electrical interference on consonant and vowel discrimination were investigated in five patients with implanted subdural electrode arrays. Without electrical interference, patients performance discriminating consonants and vowels was intact. With electrical interference, consonant discrimination was impaired at one electrode site in each patient on the superior temporal gyrus of the lateral left perisylvian cortex. Conversely, vowel and tone discrimination remained relatively intact when tested with electrical interference at the same site. Analysis of patients' consonant discrimination errors revealed that neither differences in acoustic temporal structure nor syllable position fully account for the consonant-vowel perceptual dissociations elicited. Our data suggest that at the cortical level consonant and vowel perception are intrinsically distinct perceptual phenomena. The selective impairment of consonant, but not vowel, discrimination further suggests that consonant and vowel perception are distinguished by differences in relative dependence on the functional--perhaps integrative--resources of the left lateral superior temporal gyrus.

Habituation, sensitization, and infants' responses to motherese speech.

Four-month-old infants were tested for their visual responses to infant-directed (ID) speech versus adult-directed (AD) speech in a fixed-trial habituation procedure. In Experiment I, infants looked significantly longer in response to a 4 x 4 checkerboard pattern that was compounded with an ID speech segment than an AD speech segment. Looking times increased significantly between the first and second presentations of the ID speech segment only. In Experiment II, infants looked slightly more during ID than AD trials when the two were alternated from trial to trial. Responding to the first AD speech segment was significantly greater than when it was preceded by ID speech than when it was not, while responding to the first ID speech segment was significantly less when it was preceded by AD speech than when it was not. These findings are discussed in relation to the hypothesized differential arousing properties of ID and AD speech.

Voiced-speech representation by an analog silicon model of the auditory periphery.

An analog CMOS integration of a model for the auditory periphery is presented. The model consists of middle ear, basilar membrane, and hair cell/synapse modules which are derived from neurophysiological studies. The circuit realization of each module is discussed, and experimental data of each module's response to sinusoidal excitation are given. The nonlinear speech processing capabilities of the system are demonstrated using the voiced syllable |ba|. The multichannel output of the silicon model corresponds to the time-varying instantaneous firing rates of auditory nerve fibers that have different characteristic frequencies. These outputs are similar to the physiologically obtained responses. The actual implementation uses subthreshold CMOS technology and analog continuous-time circuits, resulting in a real-time, micropower device with potential applications as a preprocessor of auditory stimuli.