Restoration of spinal alignment and disk mechanics following polyetheretherketone wafer kyphoplasty with StaXx FX.

BACKGROUND AND PURPOSE: EPFs sustained during VCFs degrade the disk's ability to develop IDP under load. This inability to develop pressure in combination with residual kyphotic deformity increases the risk for adjacent vertebral fractures. We tested the hypothesis that StaXx FX reduces kyphosis and endplate deformity following vertebral compression fracture, restoring disk mechanics. MATERIALS AND METHODS: Eight thoracolumbar, 5-vertebrae segments were tested. A void was selectively created in the middle vertebra. The specimens were compressed until EPF and to a grade I-II VCF. PEEK wafer kyphoplasty was then performed. The specimens were then tested in flexion-extension (±6 Nm) under 400-N preload intact, after EPF, VCF, and kyphoplasty. Endplate deformity, kyphosis, and IDP adjacent to the fractured body were measured. RESULTS: Vertebral body height at the point of maximal endplate deformity decreased after EPF and VCF and was partially corrected after StaXx FX, remaining less than intact (P = .047). Anterior vertebral height decreased after VCF (P = .002) and was partially restored with StaXx FX, remaining less than intact (P = .015). Vertebral kyphosis increased after VCF (P < .001) and reduced after StaXx FX, remaining greater than intact (P = .03). EPF reduced IDP in the affected disk in compression-flexion loading (P < .001), which was restored after StaXx FX (P = 1.0). IDP in the unaffected disk did not change during testing (P > .3). CONCLUSIONS: StaXx FX reduced endplate deformity and kyphosis, and significantly increased anterior height following VCF. Although height and kyphosis were not fully corrected, the disk's ability to pressurize under load was restored.

Changes in regional cerebral blood flow after electroconvulsive therapy for depression.

Fifteen patients with major depression and normal results of magnetic resonance imaging or computed tomographic studies were treated by electroconvulsive therapy (ECT). The regional cerebral blood flow (rCBF) of these patients was imaged using Tc-99m hexamethylpropylene amineoxime single-photon emission computed tomography before and after treatment, and their images were compared with a population of 11 healthy volunteers. Before ECT treatment, the patients had hypoperfusion of the frontal region compared with the controls, and they had multiple areas of altered perfusion throughout the brain. Five of the patients had an excellent clinical response to ECT; these patients also showed changes toward normal in rCBF. The remaining patients had minimal to moderate clinical response and showed no significant change in rCBF. These results indicate that improvement in clinical status as a result of ECT is correlated with a change toward normal in rCBF.

Effect of carbonated water on gastric emptying and intragastric meal distribution.

Carbonated water has long been advocated to relieve dyspeptic symptoms, suggesting that it may alter gastric motility via gastric distension. This study aimed to determine the effect of carbonated water on gastric emptying of a radiolabeled mixed meal in eight healthy volunteers. Meal emptying and its distribution within the stomach were assessed with carbonated and still water in a crossover study. Emptying of both solid and liquid, including the duration of the lag phase, was identical for both drinks. However, the proximal stomach contained a greater proportion of solids (74 +/- 7% vs 56 +/- 8%, P < 0.05) and liquids (43 +/- 5% vs 27 +/- 4%, P < 0.05) with carbonated water as opposed to still water. Retention of the meal within the proximal stomach ended with the lag phase and was likely related to proximal distension. In conclusion, carbonated water did not alter overall gastric emptying but profoundly modified intragastric distribution of the meal.

Weekly and yearly rhythms in plasma fibrinogen in hospitalized male military veterans.

The variation in plasma fibrinogen level demonstrating prominent circaseptan and circannual cycles is clinically relevant. There is a correlation between increasing level of fibrinogen and other hemostatic factors and risk of myocardial infarction and sudden death. The circaseptan and circannual cycles in fibrinogen concentration described in this study may help to explain further the variation in frequency of coronary events. Furthermore, the recent demonstration of a circadian pattern in the efficacy of tissue plasminogen activator, with peak efficacy occurring at 2000 hours--10 hours after the peak incidence of myocardial infarction--implies that further patterns to coronary artery syndromes may be predicted and the treatment efficacy may rely on demonstrated circaseptan and circannual cycles of these events.