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991.
Radiologic measures of migration percentage (MP) and acetabular index (AI) taken from plain radiographs of the pelvis are the most commonly used tools for determining hip displacement and management options in children with cerebral palsy and spastic hip disease. This study determined interrater and intrarater reliability of MP and AI on pelvic radiographs chosen to represent a wide range of age (11 months to 8 years 5 months), MP (0%-56%), and AI (9 degrees -33 degrees ). The study demonstrated that an experienced rater would be expected to measure MP on a single radiograph to within +/-5.8% of the true value and a change in MP between two radiographs taken at different times to within +/-8.3% of the true value. Similarly for AI, the measurement error for a typical rater would be within +/-2.6 degrees on a single reading and +/-3.7 degrees if recording change between two occasions. The authors believe that the results indicating true change are acceptable in clinical practice, provided treatment decisions are based on a series of radiographs taken at 6-month intervals, methods and training are standardized, and consistent raters are used.  相似文献   
992.
We have reported a large study of patients admitted to hospital following head injury in the city of Glasgow over one calendar year. This showed 1000 patients still to be disabled one year after their injury. In order to see whether the difficulties reported by these patients represented needs for rehabilitation services, we undertook a parallel study in which a separate group of 26 patients were assessed by the same methods as in the main group, but also had a clinical review by an experienced rehabilitation medicine physician, to determine the patient's rehabilitation needs. The physician was unaware of the results of the first assessment.

Both the extent and the nature of the services as needed were reported remarkably similarly by each form of assessment. In addition, the Glasgow Outcome Scale categories were closely related to the need for services.

We conclude that the data reported by Thornhill et al. can be used to estimate the volume and type of rehabilitation services required by head injured patients in the early months after injury.  相似文献   
993.
We have reviewed the outcome of 134 hips in 96 children with Graf type-III or type-IV dysplasia of the hip on ultrasound examination. We treated 28 affected hips in 22 children with the Craig splint, 43 hips in 30 children with the Pavlik harness, and 26 hips in 16 children with the von Rosen splint. A total of 37 affected hips in 28 children was not splinted. All children were less than three months of age at referral. Those treated with the von Rosen splint had a significantly better ultrasound appearance at 12 to 20 weeks of age and fewer radiological abnormalities than those not splinted or treated with the Pavlik harness. In the von Rosen group no hip required further treatment with an abduction plaster or operation compared with ten in the Pavlik harness group, three in the Craig splint group and eight in the group without splintage. Our results suggest that the von Rosen splint is more likely to improve the outcome of neonatal dysplasia of the hip and a definitive, large-scale randomised trial is therefore indicated.  相似文献   
994.
There are few long-term follow-up reports of the Angelchik prosthesis (AP). We report the longest follow-up series (66-192 months, average 145 months) to date. Between October 1983 and January 1994, 65 patients (45 men and 20 women) aged between 29 and 84 years (mean 52 years) had an AP inserted for gastro-oesophageal reflux (GOR) with or without hiatus hernia (HH). Clinical, radiological, endoscopy, and operative details were reviewed. Postoperative complications, investigations, and follow-up details were critically analyzed. All living patients (n = 53) with an AP in situ were interviewed and symptomatic assessment was carried out using a modified Visick system (I-IV). The average duration of the GOR symptoms before the operation was 5.7 years (range 10 months to 20 years). The average hospital stay was 8 days (range 5-15 days). Postoperatively, five patients developed chest infection/atelectasis, four had superficial wound infection, two had deep vein thrombosis (one with pulmonary embolism), one had urinary retention, and four developed an incisional hernia. Six patients (three with an AP in situ) died of other medical conditions. Ten (15%) patients had removal of the prosthesis. Eight (12%) and 11 (17%) had transient and persistent dysphagia, respectively. Thirteen (20%) and five (8%) patients had distal slippage and proximal migration of the prosthesis, respectively. One patient had erosion of the AP into the stomach, while in another patient, the straps of the prosthesis ruptured. Of the 53 living patients with an AP in situ, 28 (53%) were Visick I, 11 (20%) were Visick II, 11 (20%) were Visick III, and 3 (7%) were Visick IV. We conclude that the AP has poor long-term results, with only 66% attaining Visick I and II, and a prosthesis removal rate of 15% (10/65). Patients with preoperative dysphagia, hypothyroidism, and diabetes tend to do worse with an AP. Obese patients and those with failed previous fundoplication seemed to fare well with an AP. In view of poor long-term results and high incidence of complications as compared to other conventional operations for GOR, we cannot recommend the continued use of the AP.  相似文献   
995.
The purpose of this work was to electrically activate small-diameter motor fibers in the sacral anterior roots innervating the urinary bladder, without activating the large-diameter fibers to the sphincter. Quasitrapezoidal current pulses were applied through tripolar spiral nerve electrodes on selected anterior sacral roots during acute experiments on eight dogs, maintained under pentobarbital anesthesia. Pressures were recorded from the bladder and sphincter with catheter-mounted gauges. Stimulation with biphasic quasitrapezoidal pulses showed decrease in sphincter recruitment with increasing pulse amplitudes. The minimum current amplitude that resulted in maximum sphincter suppression was used to stimulate the roots with trains of 20 Hz pulses, with 60 mL of saline filling the bladder. Pressures were also recorded when 100 micros rectangular pulse trains at 20 Hz, both continuous and intermittent, were applied. Trains of stimuli were applied before and after dorsal root rhizotomy. Suppression of sphincter activation was defined to be a percentage, [(Maximum pressure -Minimum pressure)/Maximum pressure x100. The results from 22 roots in eight animals show that with single pulses, the average percentage suppression of sphincter activation was 76.3% (+/-14.0). The minimum current for maximum sphincter suppression was 1.29 mA (+/-0.62). The average bladder pressure evoked was 50 cm of water during pulse train stimulation, with no significant difference due to pulse type. With pulse trains, the sphincter pressures were significantly higher when the bladder was filled. Evacuation of fluid occurred in three animals with average flow rates of 1.0 mL/s.  相似文献   
996.
997.
PURPOSE: To measure the effect of hypoxia and eye closure on epithelial permeability to fluorescein (P(dc)) during rigid lens extended wear (EW). METHODS: Central corneal thickness (CT) and P(dc) were measured in 42 subjects with an optical pachometer and automated scanning fluorophotometer, respectively. All subjects had been successfully wearing rigid gas-permeable (RGP) lenses on a 6-night EW regimen, and each individual was randomized to wear either medium- or high-oxygen-permeable (Dk) RGP lenses (two types of siloxane-fluorocarbon polymer lenses with Dk of 49 and 92). CT and P(dc) measurements were performed at an afternoon visit (baseline) and were repeated in the morning after 8 hours of overnight wear. Subjects slept with a patch over the right eye. The patch was not removed until immediately before the morning measurement. RESULTS: The mean overnight swelling response for subjects in the medium-Dk group was greater than that in the high-Dk group. Results of a paired t-test indicate that the eye wearing the medium-Dk lens with a patch overnight had a significant increase in epithelial permeability. Results of mixed-effect models suggest that eye closure and lens-induced hypoxia are significant factors in altering P(dc). CONCLUSIONS: The results indicate that corneal epithelial permeability increases with hypoxic dose and that epithelial barrier function is impaired by overnight rigid lens wear.  相似文献   
998.
Acanthamoeba sclerokeratitis: treatment with systemic immunosuppression   总被引:1,自引:0,他引:1  
OBJECTIVE: This study describes the clinical features, management, and outcome of 19 patients who had severe Acanthamoeba sclerokeratitis (ASK) unresponsive to conventional management, requiring systemic immunosuppression to control disease. DESIGN: Retrospective, non-comparative, interventional case series. PARTICIPANTS: Records of all patients with Acanthamoeba keratitis treated at Moorfields Eye Hospital between 1989 and 2000 were reviewed. From more than 200 patients, 19 who developed ASK treated with systemic immunosuppression were identified. MAIN OUTCOME MEASURES: Visual acuity, level of pain, and degree of inflammation were recorded after immunosuppressive treatment. RESULTS: ASK requiring immunosuppression occurred in 20 eyes of 19 patients (11 males and 8 females). The mean age (mean +/- standard deviation) at onset was 38.6 +/- 13.2 years. On presentation, best-corrected visual acuity was counting fingers or worse in 11 eyes (55%), 6/18 to 6/60 in 5 eyes (25%), and 6/12 or better in 4 eyes (20%). The mean time between onset of initial symptoms of Acanthamoeba keratitis and commencement of systemic immunosuppression was 4.8 +/- 3.5 months. The mean duration of immunosuppression required to control inflammation was 7.2 +/- 3.9 months. Severe scleritic pain remained uncontrolled in two patients and resulted in enucleation. Best-corrected visual acuity at final follow-up was counting fingers or worse in eight eyes (40%), 6/18 to 6/60 in six eyes (30%), and 20/40 or better in six eyes (30%). The mean follow-up period after resolution of inflammation was 24.3 +/- 20.9 months (range, 0.2-59.7 months). CONCLUSIONS: ASK is an uncommon complication of Acanthamoeba keratitis. The scleritis associated with this infection seems to be an immune-mediated response. After topical amebicidal treatment, systemic immunosuppression may be required to control the pain and tissue destruction associated with ASK.  相似文献   
999.
Background: As a multifactorial disease, glaucoma may be associated with pressure‐dependent and pressure‐independent factors. Ocular hypertension (OHT) may develop into primary open angle glaucoma (POAG) for many patients. Groups with OHT and POAG were compared for pressure‐dependent and independent risk factors. A high prevalence of any factor(s) could indicate a contribution to progression from OHT to POAG. Methods: A sample of patients with POAG (n = 438) and with OHT (n = 301) were selected from those attending a tertiary referral private glaucoma practice, and data were collected regarding age and intraocular pressure at the time of diagnosis, sex, family history of glaucoma, systemic hypertension, diabetes, Raynaud's phenomenon, migraine and myopia. Results: After multivariate analysis, older age at time of diagnosis (χ25 = 73.89, P < 0.001), myopia (odds ratio [OR] = 1.5, 95% confidence interval [CI] 1.0?2.2; P < 0.05), a family history of glaucoma (OR = 1.6, 95% CI 1.1?2.3; P < 0.01) and a high intraocular pressure (χ24 = 16.96; P = 0.002) were found to be more prevalent among those with POAG. No other significant differences could be found between the two groups. Conclusion: Patients who have OHT may be at higher risk of developing POAG if they also have myopia, a family history of glaucoma or are of older age.  相似文献   
1000.
The corneal thickness and intraocular pressure story: where are we now?   总被引:6,自引:0,他引:6  
A review of the current literature was conducted regarding the effect of corneal thickness on the diagnosis of glaucoma, and the influence of excimer laser refractive surgery on intraocular pressure (IOP) measurement with Goldmann applanation tonometry. In general, normals and primary open angle glaucoma patients have a similar distribution of corneal thickness; however, there is a wide variation, ranging from 427 to 716 micro m. Normal tension glaucoma patients have a tendency towards thinner corneas than normals; however, there is an overlap of thickness measurements of more than two-thirds in 95% of patients. There is a trend for ocular hypertensives to have thicker corneas than normals, but again there is an overlap of about one-third in 95% of patients. The general trend after excimer laser refractive surgery is for a decrease in IOP, with a mean fall in IOP measured of 0.63 mmHg per dioptre correction. There is, however, a large scatter of values with some patients having the same or lower IOP post-laser, but with other patients measuring higher pressures. Corneal thickness can influence IOP measurement by Goldmann applanation tonometry; however, the magnitude of the effect is subject to much individual variation.  相似文献   
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