Percent spinal canal compromise on MRI utilized for predicting the need for surgical treatment in single-level lumbar intervertebral disc herniation

BACKGROUND CONTEXT: There is limited information describing the correlation between the initial quantitative measurements on magnetic resonance imaging (MRI) scans of disc herniation area, canal cross-section areas, percent canal compromise, and disc herniation location to the need for surgery. PURPOSE: Our aim is to determine if the size of disc herniation area, canal cross-section area, percent canal compromise, and disc herniation location taken from MRI images of patients with symptomatic single-level lumbar herniated intervertebral discs upon initial presentation to a spine surgeon, were predictive of the need for surgical treatment. STUDY DESIGN/SETTING: This is a retrospective case matched study of patient MRI images in the senior author's private practice. PATIENT SAMPLE: From a pool of 332 patients with sciatica caused by lumbar intervertebral disc herniations at our institution, 65 patients had surgery, of which MRI images were available and analyzed on 44 patients. Forty-four additional patients were randomly selected from the remaining 267 original group as nonoperative controls. METHODS: The axial MRI image showing the largest canal compromise by the herniated disc was selected for measurements. Using T1- and T2-weighted images, the areas of interest were digitally scanned at high resolution. The canal area and disc herniation area measurement were calculated from the total number of pixels per cross-sectional area, multiplied by a scan correction factor, mm(2) /pixel. Disc herniation locations were classified into either central or paracentral. The percent canal compromise was obtained by disc herniation area divided by canal cross-section area and multiplied by 100. RESULTS: The surgical group's overall mean herniated disc area was 219.6 square millimeter (mm(2)), 179.8 at L4-5, and 267.4 at L5-S1. The nonoperative group's overall mean herniated disc area was 178.4 mm(2), 135.1 at L2-3, 160.3 at L4-5, and 207.4 at L5-S1. The surgical group's overall mean canal cross-sectional area was 471.8 mm(2), 418.6 at L4-5, and 535.6 at L5-S1. The nonoperative group's overall mean canal cross-sectional area was 541.3 mm(2), 518.1 at L2-3, 446.8 at L4-5, and 669.9 at L5-S1. The overall percent canal compromise ratio in the surgery group was 46.7%, 44.1% at L4-5, and 49.8% at L5-S1. The overall percent canal compromise in the nonoperative group was 34.2%, 34.1% at L2-3, 36.1% at L4-5, and 31.8% at L5-S1. The percent canal compromise in central herniations at L4-5 level was 53.0% in the surgical group, and 32.8% in the nonoperative group; at the L5-S1 level surgical group percent canal compromise was 64.1% and in the nonoperative group canal compromise was 27%. L4-L5 level paracentral herniations canal compromise was 36.7% in the surgical group compared with 42.5% canal compromise in the nonoperative group. At the L5-S1 level the canal compromise was 45% in the surgical group and 34.8% in the nonoperative group. CONCLUSIONS: Our findings show a trend for patients treated with surgery to have larger disc herniation areas and smaller canal cross-section areas, corresponding to larger percent canal compromise than the nonoperative group. Centrally located herniations followed this trend closely at all levels studied. However, the paracentral herniation at the L4-5 level does not follow this trend, possibly because paracentral disc herniation clinical course is determined more by herniation location rather than the overall herniation size.     

Use of the Arndt wire-guided endobronchial blocker via nasal for one-lung ventilation in patient with anticipated restricted mouth opening for esophagectomy.

Functional separation of the lungs may be accomplished by several methods. Patient with restricted mouth opening has limited options for one-lung ventilation. We report the use of wire-guided endobronchial blockade, a new tool for achieving one-lung ventilation in a patient with restricted mouth opening requiring nasotracheal, fiberoptic intubation for esophagectomy and reconstruction with gastric tube substitution.     

Development of grating acuity in infants with regressed stage 3 retinopathy of prematurity

The acuity card procedure was used to measure grating acuity in 17 infants with regressed Stage 3 retinopathy of prematurity (ROP) who had no lasting anatomic changes in the retina or optic nerve. Results were compared with those of 28 healthy preterm infants and 28 infants matched by birth weight and gestational age who did not have Stage 3 ROP. Infants in the ROP group showed delayed grating acuity development until 2 years of age. This difference among groups was significant at the 3-5- and 10-12-month test ages but not at the 0-1-, 8-9-, and 16-18-month test ages. Post hoc analyses indicated that the delay in acuity development shown by the ROP group was due to the poor acuity scores of the infants in that group who had central nervous system abnormalities of periventricular leukomalacia or severe (Grade III or IV) intraventricular hemorrhage. When the data of these infants were removed from the analysis, the ROP group showed acuity development similar to that of both the healthy preterm group and the group of infants with matched birth weights and gestational ages who did not have Stage 3 ROP.     

Using a supervisory framework to support and evaluate a multiproject practice development programme

? The paper describes a multiproject practice development programme undertaken over a period of 1 year. ? The background and development of the programme are outlined, whilst attention is paid to the innovatory nature of the work, particularly the use of inductive, deductive and integrated approaches to both change implementation and project supervision. ? The programme was monitored throughout using different data sources and the paper uses evaluative material retrospectively to provide answers to organizational and professional difficulties which arose during the course of the programme. ? The authors conclude that the use of combinations of different models for practice development has potential, but requires careful supervision. ? They also recommend that those involved in practice development are made fully aware of its local or micropolitics, and develop strategies to deal with change before it occurs, not after it has taken place.     

Diphenhydramine kinetics following intravenous, oral, and sublingual dimenhydrinate administration

Eight healthy volunteers received 50 mg of dimenhydrinate, a theoclate salt of diphenhydramine, orally, sublingually, and intravenously on three separate occasions in random sequence. Plasma diphenhydramine concentrations during 12 h after each dose were measured by gas-liquid chromatography with nitrogen-phosphorous detection. Mean peak plasma concentrations after sublingual administration were slightly lower than after oral dosage (38.3 vs 47.8 ng ml-1), and the time of peak concentration was similar (2.6 vs 2.3 h after dose). These differences did not reach statistical significance. The mean total area under the plasma concentration-time curve (AUC) for sublingual administration was slightly but not significantly smaller than after oral dosage (221 vs 270 h ng ml-1). Systemic availability of diphenhydramine after sublingual dimenhydrinate, measured by the ratio of oral AUC to intravenous AUC, was slightly less than after oral dimenhydrinate (0.58 vs 0.69, NS), and both were significantly less than 1.0. Thus sublingual and oral administration of dimenhydrinate result in comparable, but incomplete, systemic availability of diphenhydramine.     

Effects of haloperidol on motor and cognitive functioning in aged mice

The effects of haloperidol on motor and functioning and cognitive functioning were studied in young (3-5 months old) and aged (20-22 months old) male mice by examining haloperidol-induced catalepsy and haloperidol-induced decrements in performance on a radial arm maze. The aged mice were much more sensitive to these adverse effects of haloperidol than were the young mice. Studies of the distribution of radioactivity from [3H]haloperidol to the brain indicated that the differences in sensitivity to this drug were not due to pharmacokinetic differences. The results demonstrate that mice are suitable for studies of aging-induced changes in the behavioral effects of neuroleptic agents.