PubMed Health⌕ Search

Biomedical subjects

Richard W Hertle

Publications and source records attributed to Richard W Hertle.

At least 19 recordsLinked to original sources
PubMed2006

Mutations in FRMD7, a newly identified member of the FERM family, cause X-linked idiopathic congenital nystagmus.

Idiopathic congenital nystagmus is characterized by involuntary, periodic, predominantly horizontal oscillations of both eyes. We identified 22 mutations in FRMD7 in 26 families with X-linked idiopathic congenital nystagmus. Screening of 42 singleton cases of idiopathic congenital nystagmus (28 male, 14 females) yielded three mutations (7%). We found restricted expression of FRMD7 in human embryonic brain and developing neural retina, suggesting a specific role in the control of eye movement and gaze stability.

Brain↗
PubMed2006

Eye movement recordings as an effectiveness indicator of gene therapy in RPE65-deficient canines: implications for the ocular motor system.

PURPOSE: To perform ocular motility recordings of infantile nystagmus (IN) in RPE65-deficient canines and determine whether they can be used as a motor indicator of restored retinal function to investigate the effects of gene therapy. METHODS: Treated and untreated canines were comfortably suspended in a custom-built sling and encouraged to fixate on distant targets at gaze angles varying between +/-15 degrees horizontally and +/-10 degrees vertically. Ocular motility recordings were made, using two distinct methods-infrared reflection and high-speed video. The resultant recordings from three untreated, four treated, and three pre- and post-treatment dogs were analyzed for using the eXpanded Nystagmus Acuity Function (NAFX), which yields an objective assessment of best potential visual acuity, based on the duration and repeatable accuracy of foveation and centralisation. RESULTS: During fixation, the untreated dogs exhibited large-amplitude, classic IN waveforms, including pendular and jerk in both the horizontal and vertical planes, which prevented them from keeping the targets within the area centralis (the region of highest receptor density, spanning +/-3 degrees horizontally by +/-1.5 degrees vertically, analogous to the fovea). Some untreated dogs also had small-amplitude (0.5-1 degrees), high-frequency (6-9 Hz) oscillations. Under the same conditions, successfully treated canines no longer exhibited clinically detectable IN. Their IN was converted to waveforms with very low amplitudes that yielded higher NAFX values and allowed target images to remain well within the area centralis. Of note, uniocular treatment appeared to damp the IN in both eyes. Behaviorally, the treated dogs were able to successfully navigate through obstacles more easily without inadvertent contact, a task beyond the untreated dogs' ability. CONCLUSIONS: Gene therapy that successfully restored retinal function also reduced the accompanying IN to such a great extent that it was not clinically detectable approximately 90% of the time in many of the dogs. IN improvement, as quantified by the NAFX, is an objective motor indicator of visual improvement due to gene therapy.

Animals↗
PubMed2005

Two-year follow-up of a 6-month randomized trial of atropine vs patching for treatment of moderate amblyopia in children.

OBJECTIVE: To compare patching and atropine sulfate as treatments for moderate amblyopia in children 18 months after completion of a 6-month randomized trial. METHODS: In a randomized, multicenter (47 sites) clinical trial, 419 children younger than 7 years with amblyopia (20/40 to 20/100 in the affected eye) were assigned to receive either patching or atropine eye drops for 6 months. Between 6 months and 2 years, treatment was at the discretion of the investigator. Main Outcome Measure Visual acuity in the amblyopic eye and sound eye after 2 years. RESULTS: At 2 years, visual acuity in the amblyopic eye improved from baseline a mean of 3.7 lines in the patching group and 3.6 lines in the atropine group. The difference in visual acuity between treatment groups was small: 0.01 logMAR (95% confidence interval, -0.02 to 0.04). In both treatment groups, the mean amblyopic eye acuity was approximately 20/32, 1.8 lines worse than the mean sound eye acuity, which was approximately 20/20. CONCLUSIONS: Atropine or patching for 6 months followed by best clinical care until 2 years produced similar improvement of moderate amblyopia in children between 3 and 7 years of age at enrollment. However, on average the amblyopic eye acuity was still approximately 2 lines worse than the sound eye.

Amblyopia↗
PubMed2005

Randomized trial of treatment of amblyopia in children aged 7 to 17 years.

OBJECTIVE: To evaluate the effectiveness of treatment of amblyopia in children aged 7 to 17 years. METHODS: At 49 clinical sites, 507 patients with amblyopic eye visual acuity ranging from 20/40 to 20/400 were provided with optimal optical correction and then randomized to a treatment group (2-6 hours per day of prescribed patching combined with near visual activities for all patients plus atropine sulfate for children aged 7 to 12 years) or an optical correction group (optical correction alone). Patients whose amblyopic eye acuity improved 10 or more letters (> or =2 lines) by 24 weeks were considered responders. RESULTS: In the 7- to 12-year-olds (n = 404), 53% of the treatment group were responders compared with 25% of the optical correction group (P<.001). In the 13- to 17-year-olds (n = 103), the responder rates were 25% and 23%, respectively, overall (adjusted P = .22) but 47% and 20%, respectively, among patients not previously treated with patching and/or atropine for amblyopia (adjusted P = .03). Most patients, including responders, were left with a residual visual acuity deficit. CONCLUSIONS: Amblyopia improves with optical correction alone in about one fourth of patients aged 7 to 17 years, although most patients who are initially treated with optical correction alone will require additional treatment for amblyopia. For patients aged 7 to 12 years, prescribing 2 to 6 hours per day of patching with near visual activities and atropine can improve visual acuity even if the amblyopia has been previously treated. For patients 13 to 17 years, prescribing patching 2 to 6 hours per day with near visual activities may improve visual acuity when amblyopia has not been previously treated but appears to be of little benefit if amblyopia was previously treated with patching. We do not yet know whether visual acuity improvement will be sustained once treatment is discontinued; therefore, conclusions regarding the long-term benefit of treatment and the development of treatment recommendations for amblyopia in children 7 years and older await the results of a follow-up study we are conducting on the patients who responded to treatment.

Adolescent↗
PubMed2005

Gaze-dependent and time-restricted visual acuity measures in patients with Infantile Nystagmus Syndrome (INS).

PURPOSE: We report a new method of measuring visual function in patients with INS by demonstrating the effects of eccentric gaze and forced time restriction on optotype recognition. DESIGN: Cross-sectional, comparative case-series. METHODS: No-time-restricted acuity (NTRA) and time-restricted acuity (TRA) for 19 patients and 18 controls were measured at multiple horizontal gaze angles. RESULTS: INS patients showed a significant lower visual acuity than controls (P < 0.0001). The TRA were significantly decreased in most gaze positions relative to NTRA in INS patients (P = 0.03) while there were no difference among controls. About half of the INS patients showed that their best visual acuity was gaze dependent, matching the preferred head posture in both NRTA and TRA paradigms. CONCLUSIONS: Gaze-dependent visual acuity tested with and without time restriction may be a useful measure of visual function in INS patients and could be used in interventional clinical trials.

Adult↗
PubMed2005

X-linked infantile periodic alternating nystagmus.

OBJECTIVE: To describe the clinical and electrophysiological characterization of four family members from three generations who have X-linked infantile periodic alternating nystagmus (XIPAN). METHODS: Complete clinical ophthalmological evaluation, pedigree analysis, electroretinograms (ERG), eye movement recordings (EMR), color vision, and fundus photography were performed on all subjects. RESULTS: Three males in two generations and one female were examined. Clinical examinations showed a jerk/pendular nystagmus with a latent component, strabismus, and a significant refractive error in the three affected males, while the female had only myopic astigmatism. ERG, color contrast, and fundus examinations were normal in all four family members. All four family members showed EMR abnormalities with infantile jerk/dual jerk and pendular nystagmus waveforms. The female had nystagmus present on EMR only and all patients showed (a)periodicity to their nystagmus. CONCLUSIONS: In this family with no other congenital visual sensory system disease, affected males had obvious periodic alternating nystagmus, strabismus, and refractive errors, while the female had clinically "silent" periodic nystagmus that is probably a marker for the carrier state.

Adult↗
PubMed2004

Effects of extraocular muscle surgery on 15 patients with oculo-cutaneous albinism (OCA) and infantile nystagmus syndrome (INS).

PURPOSE: The purpose of this report is to characterize the clinical and electrophysiological effects of extraocular muscle surgery in 15 patients with oculo-cutaneous albinism (OCA) and infantile nystagmus syndrome (INS). Our hypothesis is that surgery on the extraocular muscles of patients with OCA and INS changes their nystagmus and their visual function. DESIGN: Interventional, prospective, cohort, noncomparative case series. METHODS: All 15 patients had surgery on all four virgin horizontal recti; three for strabismus alone, three for nystagmus alone, five for an eccentric gaze null zone alone, and four for an eccentric gaze null zone plus strabismus. All patients have been followed for at least six months. All 15 patients had the subjective outcome measure of pre- and postoperative binocular best optically corrected acuity (BBOCA). Objective outcome measures included anomalous head posture (AHP) in nine patients, eye movement recording measures of expanded nystagmus acuity function (NAFX) in 10 patients, null zone position (NUZP) and null zone width (NUZW) in 10 patients, and foveation time (FOV) in nine patients. RESULTS: The results are summarized as follows; BBOCA increased 0.1 LogMar or greater in 14 of 15 patients. In those operated on for an AHP with or without associated strabismus the AHP improved significantly (P < .01 for all). The NAFX, NUZP, NUZW, and FOV measured from eye movement recordings showed persistent, significant increases in all patients (P < .01 for all). CONCLUSIONS: This report adds to the evidence that surgery on the extraocular muscles in patients with INS has independent neurologic and visual results.

Adolescent↗
PubMed2004

Horizontal rectus muscle tenotomy in children with infantile nystagmus syndrome: a pilot study.

PURPOSE: We wished to determine the effectiveness of horizontal rectus tenotomy in changing the nystagmus of children with infantile nystagmus syndrome. DESIGN: This was a prospective, noncomparative, interventional case series in five children with varied sensory and oculographic subtypes of congenital nystagmus (including asymmetric (a)periodic alternating nystagmus) and no nystagmus treatment options. Simple tenotomy of all four horizontal recti with reattachment at the original insertion was accomplished. Search-coil and infrared eye movement recordings and clinical examinations were performed before and 1, 6, 26, and 52 weeks after surgery. Outcome measures included masked pre- and postoperative expanded nystagmus acuity function (NAFX), foveation time obtained directly from ocular motility recordings, and masked measures of visual acuity. RESULTS: At 1 year after tenotomy and under binocular conditions, two of the three patients for whom the NAFX could be measured had persistent, significant postoperative increases in the NAFX of their fixating eye. Average foveation times increased in these patients' fixating eyes. Measured binocular visual acuity increased in four patients; the remaining patient had retinal dystrophy. There were no adverse events due to surgery. CONCLUSIONS: In the two children who could fixate the targets for several seconds and for whom we could obtain accurate measurements of their infantile nystagmus, tenotomy resulted in significant improvements in nystagmus foveation measures. In those patients plus two others (four of five), measured visual function improved.

Adolescent↗
PubMed2004

A randomized trial of atropine regimens for treatment of moderate amblyopia in children.

OBJECTIVE: To compare daily atropine to weekend atropine as prescribed treatments for moderate amblyopia in children younger than 7 years. DESIGN: Prospective, randomized multicenter clinical trial (30 sites). PARTICIPANTS: One hundred sixty-eight children younger than 7 years with amblyopia in the range of 20/40 to 20/80 associated with strabismus, anisometropia, or both. INTERVENTION: Randomization either to daily atropine or to weekend atropine for 4 months. Partial responders were continued on the randomized treatment until no further improvement was noted. MAIN OUTCOME MEASURE: Visual acuity (VA) in the amblyopic eye after 4 months. RESULTS: The improvement in VA of the amblyopic eye from baseline to 4 months averaged 2.3 lines in each group. The VA of the amblyopic eye at study completion was either (1) at least 20/25 or (2) better than or equal to that of the sound eye in 39 children (47%) in the daily group and 45 children (53%) in the weekend group. The VA of the sound eye at the end of follow-up was reduced by 2 lines in one patient in each group. Stereoacuity outcomes were similar in the 2 groups. CONCLUSIONS: Weekend atropine provides an improvement in VA of a magnitude similar to that of the improvement provided by daily atropine in treating moderate amblyopia in children 3 to 7 years old. This article contains additional online-only material available at http://www.ophsource.com/periodicals/ophtha.

Amblyopia↗
PubMed2004

Retinal detachment from inadvertent intraocular injection of botulinum toxin A.

PURPOSE: To report a case of inadvertent intraocular injection of botulinum toxin A (Botox, BTA) resulting in a retinal tear and bullous retinal detachment. The retinal detachment resolved spontaneously, and the tear was treated with laser demarcation with good visual outcome. DESIGN: Interventional case report. METHODS: A 36-year-old woman underwent Botox injections for paralytic esotropia and developed ocular perforation. Dilated fundus examination showed a slit-like retinal tear infranasally with a bullous retinal detachment nasally. RESULTS: The retinal detachment spontaneously resolved, and the patient was treated with laser demarcation on the following day. After 2 more days, her vision returned to baseline. CONCLUSIONS: Botox did not appear toxic to human intraocular tissues. Close observation may be indicated in the event of an inadvertent intraocular Botox injection.

Adult↗
PubMed2004

Risk of amblyopia recurrence after cessation of treatment.

BACKGROUND: Although amblyopia can be successfully treated with patching or atropine, there have been few prospective studies of amblyopia recurrence once treatment is discontinued. METHODS: We enrolled 156 children with successfully treated anisometropic or strabismic amblyopia (145 completed follow-up), who were younger than 8 years of age and who received continuous amblyopia treatment for the previous 3 months (prescribed at least 2 hours of daily patching or prescribed at least one drop of atropine per week) and who had improved at least 3 logMAR levels during the period of continuous treatment. Patients were followed off treatment for 52 weeks to assess recurrence of amblyopia, defined as a 2 or more logMAR level reduction of visual acuity from enrollment, confirmed by a second examination. Recurrence was also considered to have occurred if treatment was restarted because of a nonreplicated 2 or more logMAR level reduction of visual acuity. RESULTS: Recurrence occurred in 35 (24%) of 145 cases (95% confidence interval 17% to 32%) and was similar in patients who stopped patching (25%) and in patients who stopped atropine (21%). In patients treated with moderately intense patching (6 to 8 hours per day), recurrence was more common (11 of 26; 42%) when treatment was not reduced prior to cessation than when treatment was reduced to 2 hours per day prior to cessation (3 of 22; 14%, odds ratio 4.4, 95% confidence interval 1.0 to 18.7). CONCLUSIONS: Approximately one fourth of successfully treated amblyopic children experience a recurrence within the first year off treatment. For patients treated with 6 or more hours of daily patching, our data suggest that the risk of recurrence is greater when patching is stopped abruptly rather than when it is reduced to 2 hours per day prior to cessation. A randomized clinical trial of no weaning versus weaning in successfully-treated amblyopia is warranted to confirm these observational findings.

Amblyopia↗
PubMed2003

A randomized trial of patching regimens for treatment of moderate amblyopia in children.

OBJECTIVE: To compare 2 hours vs 6 hours of daily patching as treatments for moderate amblyopia in children younger than 7 years. METHODS: In a randomized multicenter (35 sites) clinical trial, 189 children younger than 7 years with amblyopia in the range of 20/40 to 20/80 were assigned to receive either 2 hours or 6 hours of daily patching combined with at least 1 hour per day of near visual activities during patching.Main Outcome Measure Visual acuity in the amblyopic eye after 4 months. RESULTS: Visual acuity in the amblyopic eye improved a similar amount in both groups. The improvement in the visual acuity of the amblyopic eye from baseline to 4 months averaged 2.40 lines in each group (P =.98). The 4-month visual acuity was at least 20/32 and/or improved from baseline by 3 or more lines in 62% of patients in each group (P>.99). CONCLUSION: When combined with prescribing 1 hour of near visual activities, 2 hours of daily patching produces an improvement in visual acuity that is of similar magnitude to the improvement produced by 6 hours of daily patching in treating moderate amblyopia in children aged 3 to 7 years.

Amblyopia↗
PubMed2003

A randomized trial of prescribed patching regimens for treatment of severe amblyopia in children.

OBJECTIVE: To compare full-time patching (all hours or all but 1 hour per day) to 6 hours of patching per day, as prescribed treatments for severe amblyopia in children younger than 7 years. DESIGN: Prospective, randomized multicenter clinical trial (32 sites). PARTICIPANTS: One hundred seventy-five children younger than 7 years with amblyopia in the range of 20/100 to 20/400. INTERVENTION: Randomization either to full-time patching or to 6 hours of patching per day, each combined with at least 1 hour of near-visual activities during patching. MAIN OUTCOME MEASURE: Visual acuity in the amblyopic eye after 4 months. RESULTS: Visual acuity in the amblyopic eye improved a similar amount in both groups. The improvement in the amblyopic eye acuity from baseline to 4 months averaged 4.8 lines in the 6-hour group and 4.7 lines in the full-time group (P = 0.45). CONCLUSION: Six hours of prescribed daily patching produces an improvement in visual acuity that is of similar magnitude to the improvement produced by prescribed full-time patching in treating severe amblyopia in children 3 to less than 7 years of age.

Amblyopia↗
PubMed2003

Reliability of the electronic early treatment diabetic retinopathy study testing protocol in children 7 to <13 years old.

PURPOSE: To assess the test-retest reliability of the electronic Early Treatment Diabetic Retinopathy Study (E-ETDRS) visual acuity algorithm using the computerized Electronic Visual Acuity (EVA) tester in children 7 to <13 years old. DESIGN: Test-retest reliability study. METHODS: This multicenter study involved 245 subjects at four clinical sites. As the main outcome measure, visual acuity was measured twice using the E-ETDRS testing protocol on the EVA system, which uses a programmed handheld device to communicate with a personal computer and a 17-inch monitor at a 3-m test distance. RESULTS: Test-retest reliability was high (r =.94 for right eyes and 0.96 for left eyes) and for both right and left eyes, 89% of retest scores were within 0.1 logarithm of the minimal angle of resolution (logMAR) (five letters) of the initial test score and 99% of retests were within 0.2 logMAR (10 letters). Reliability was high across the age range of 7 to <13 years. Based on 95% confidence level estimates, a change in visual acuity of 0.2 logMAR (10 letters) from a previous acuity measure is unlikely to result from measurement variability. CONCLUSIONS: The E-ETDRS protocol using the EVA has high test-retest reliability in children 7 to <13 years of age. Potential advantages include better standardization across multiple sites, the ability to directly capture data electronically with an automatic acuity score calculation, the reduction of potential bias by limiting the tester's role, and the requirement of only a single testing distance for measurements from 20/800 to 20/12. This computerized testing method should be considered when visual acuity is used as an outcome measure in eye research involving children 7 to <13 years old.

Adolescent↗
PubMed2003

Effects of tenotomy surgery on congenital nystagmus waveforms in adult patients. Part I. Wavelet spectral analysis.

Congenital nystagmus (CN) is an aperiodic oscillatory eye movement disorder. Horizontal rectus tenotomy with simple re-attachment has been proposed as a therapy for CN. This therapy might affect vision and/or eye movements. Another paper deals with improvements in visual acuity. This and the companion paper examine changes in eye movements. In this study, we examined the effect of tenotomy on nystagmus waveforms using wavelet spectral analysis. No common effect was found across the patients on the wavelet spectra of the CN beat, suggesting that tenotomy surgery has no effect, or only a quite small effect, on the waveform structure of CN.

Adult↗
PubMed2003

Effects of tenotomy surgery on congenital nystagmus waveforms in adult patients. Part II. Dynamical systems analysis.

Congenital nystagmus (CN) is an aperiodic oscillatory eye movement disorder of unknown etiology. We examined the effect of horizontal rectus tenotomy with simple re-attachment on the dimensionality of the dynamical mechanism underlying CN. The correlation dimensions (CDs) were calculated from eight patients who had tenotomy surgery. We found no significant differences in the CDs that could be associated with the surgery. The change in dimensionality was less than 5% on average. The results suggest that the tenotomy has no effect, or only a quite small effect, on the underlying mechanism of the CN beats.

Adult↗
PubMed2003

Horizontal rectus tenotomy in patients with congenital nystagmus: results in 10 adults.

OBJECTIVE: We wished to determine the effectiveness of horizontal rectus tenotomy in changing the nystagmus of patients with congenital nystagmus and, secondarily, how their visual function changed. DESIGN: This was a prospective, noncomparative, interventional case series. PARTICIPANTS: Ten adult patients with varied associated sensory defects and oculographic subtypes of congenital nystagmus (including asymmetric periodic or aperiodic alternating nystagmus) and no nystagmus treatment options. METHODS: By using standard surgical techniques, simple tenotomy of all four horizontal recti with reattachment at the original insertion was accomplished. Search-coil eye movement recordings and clinical examinations were performed before and 1, 6, 24, and 52 weeks after surgery. MAIN OUTCOME MEASURES: The primary outcome measure was the expanded nystagmus acuity function, obtained in "masked" fashion directly from ocular motility recordings. Secondary outcomes included breadth of null zones, preoperative and postoperative masked measures of visual acuity (Early Treatment Diabetic Retinopathy Study [ETDRS] chart), and the National Eye Institute Visual Function Questionnaire (NEI-VFQ-25). RESULTS: At 1 year after tenotomy and under binocular conditions, 9 of 10 patients had persistent, significant postoperative increases in the expanded nystagmus acuity function of their fixing (preferred) eye; 1 remained high, and 1 was not tested under the same conditions. Average foveation times increased in all 9 fixing (preferred) eyes. Binocular visual acuity measured with the ETDRS chart increased in 5 patients and was unaffected in five, whereas the NEI-VFQ-25 showed an improvement in vision-specific mental health in 9 patients. There were no adverse events. Tenotomy also radically changed the periodicity of one patient's asymmetric periodic or aperiodic alternating nystagmus. CONCLUSIONS: In 9 of 10 adult patients with clinical and oculographic variations in their congenital nystagmus, tenotomy resulted in significant improvements in a nystagmus measure and subjective visual functions.

Adult↗