Publications by authors named "McCulloch D"

Purpose: The visual evoked potential is often used to assess visual function in neurologically impaired patients, a group in whom nystagmus is a common feature. Pattern-reversal stimuli are commonly used to produce visual evoked potentials in clinical practice. Previous reports have shown that this stimulus is not optimal when subjects have nystagmus.

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We have compared the testability and acuity thresholds achieved with vanishing optotype acuity cards and traditional grating acuity cards when used to examine children with neurological impairment. These children encompass a wide range of ages and abilities and it may be desirable to use the two types of cards for acuity assessment. Subjects were a diverse group of children (n = 91; 8 months-19 years) whose learning ability ranged from normal to severe disability.

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Scanning transmission electron microscopy (STEM), coupled with energy dispersive X-ray analysis (EDS), X-ray photoelectron spectroscopy (XPS) or radionuclear chemical methods, indicates that the active agent in Technegas is either polymeric TcO2[i.e. (TcO2)n] or (TcO2)n bound to a carbon nanoparticle.

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Intellectually disabled adults have an high incidence of visual problems and they are often unable to communicate their visual difficulties. At Lennox Castle and Waverley Park Hospitals, vision care is through referral by medical and nursing staff to designated optometrists and ophthalmologists. This practice has provided a good service when visual difficulties are noticed.

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Children who demonstrate problems with skilled movement in the absence of physical handicap are formally designated as suffering from developmental coordination disorder (DCD). Diagnosis of DCD was confirmed by the 'movement assessment battery for children'. Visually evoked potentials (VEPs) were recorded to evaluate the integrity of the visual pathway and to rule out the presence of any neurological lesions affecting visual input.

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Damage to the cerebral cortex was responsible for impairment in vision in 90 of 130 consecutive children referred to the Vision Assessment Clinic in Glasgow. Cortical blindness was seen in 16 children. Only 2 were mobile, but both showed evidence of navigational blind-sight.

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Purpose: Because there is a broad spectrum of visual dysfunction in eyes with optic nerve hypoplasia, we determined whether any clinical observations, including optic disk measurements, could predict visual outcome in eyes with hypoplastic optic nerves.

Methods: We prospectively studied the eyes of 19 children (eight consecutive and 11 randomly selected), ages 7 to 92 months, in whom a diagnosis of optic nerve hypoplasia was made by an ophthalmologist. Clinical assessment included visual acuity, pupillary responses, and nystagmus.

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Sequence variation among HLA class II promoter elements may contribute to functional differences in transcriptional regulation of different class II alleles. In addition to influencing the binding sites for nuclear transcription factors, promoter polymorphism may also alter intrinsic structural properties of the DNA strands, such as conformation and curvature, which influence the formation of stable transcription complexes. We used SSCP analysis of PCR-amplified promoter regions from the DQB1 locus to evaluate conformational polymorphism within DQ alleles.

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The authors examined refractive error, pattern onset visual evoked potentials, ocular posture and they performed internal and external eye examinations in 11 subjects with Rett syndrome (aged between four and 24 years) and 18 normal controls (aged between six and 20 years). Substantial refractive errors were common in the Rett syndrome group. Spectacle correction had never previously been worn and glasses were provided where appropriate.

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The routine use of cholinesterase inhibitors to antagonize residual neuromuscular block may be associated with increased postoperative emesis. Rapid spontaneous recovery from mivacurium may obviate the need for these drugs. In this randomized, double-blind, placebo-controlled study of 113 healthy children who had received mivacurium as part of a standardized anesthetic regimen, we compared the incidence of postoperative complications after spontaneous recovery and after the use of neostigmine-glycopyrrolate or edrophonium-atropine.

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A multicenter, retrospective survey of 339 patients with insulin-dependent diabetes mellitus was done to evaluate patient experience with Velosulin Human insulin, a regular insulin in a phosphate buffer, used in continuous subcutaneous insulin infusion. Patients had used this insulin exclusively for 3 months preceding the survey. Responses were elicited through interviews conducted by physicians or nurses.

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Visual evoked potentials can be elicited by a variety of visual stimuli, including pattern-onset and motion-onset. It may be desirable to combine pattern-onset with motion-onset stimuli, for example, to make a direct comparison between optokinetic nystagmus and visual evoked potential acuity thresholds. Both procedures employ grating stimuli; however, the gratings must be moving to produce optokinetic nystagmus.

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The aims of this study were to compare acuity estimates achieved with visual evoked potential (VEP) and acuity card techniques and to examine the success rates of each test in a group of multiply handicapped children. Subjects were 52 children (3-183 months) with multiple handicaps associated with prematurity (n = 17), congenital anomalies (n = 16), hypoxic insult (n = 10) and other disorders (n = 9). Success rates for completing the tests were: VEP 88% and acuity cards 85% (Keeler or Cardiff).

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To investigate whether drawing blood from a retrogradely cannulated hand vein rather than an antegradely cannulated arm vein improves reproducibility in the intravenous tolerance test (IVGTT) we compared these two methods directly by drawing blood from the two sites on the same arm simultaneously. We found no difference in intrasubject coefficients of variation for the measurement of insulin response to glucose (21.5% vs.

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Objective: To describe the pattern reversal visual evoked potentials (VEPs) that were used to monitor and quantify early visual development following treatment for dense, unilateral, congenital cataract.

Design: Longitudinal prospective study.

Patients: Six infants who underwent surgery and contact lens correction before age 5 months and who had good compliance with occlusion therapy throughout the first 3 years of life.

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Glucose disposal occurs by both insulin-independent and insulin-dependent mechanisms, the latter being determined by the interaction of insulin sensitivity and insulin secretion. To determine the role of insulin-independent and insulin-dependent factors in glucose tolerance, we performed intravenous glucose tolerance tests on 93 young healthy subjects (55 male, 38 female; 18-44 years of age; body mass index, 19.5-52.

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