Significance of the early postoperative duplex result in infrainguinal vein bypass surveillance.

BACKGROUND: Duplex surveillance of infrainguinal vein grafts may not be efficient. METHODS: Consecutive patients who had received infrainguinal vein grafts were enrolled in a duplex surveillance program. A first scan at 6 weeks after surgery categorized grafts into four groups: (a) low risk grafts, (b) mild flow disturbance, (c) intermediate stenosis and (d) critical stenosis. Disease progression was assessed over time. RESULTS: Of 364 grafts followed-up for a median of 23 months, 236 (65%) had no flow abnormality at 6-weeks, and had a 40-month cumulative patency rate of 82%. The remaining 128 (35%) grafts had a flow disturbance. Of 29 critical stenoses, 15 were repaired, 11 occluded and three did not change. Of 57 intermediate lesions, 32 progressed to critical, nine occluded, two were repaired and 14 did not change or improved. Of 42 mild lesions, 16 progressed to a higher grade, four occluded and 22 did not change or improved. There was no significant difference in graft patency between grafts with repaired stenoses and those without stenoses, but grafts with untreated critical stenoses were associated with lower patency (p<0.001). CONCLUSIONS: A duplex scan 6 weeks after operation can predict those patients who require continuing duplex surveillance.     

Cine CT for attenuation correction in cardiac PET/CT.

In dual-modality PET/CT systems, the CT scan provides the attenuation map for PET attenuation correction. The current clinical practice of obtaining a single helical CT scan provides only a snapshot of the respiratory cycle, whereas PET occurs over multiple respiratory cycles. Misalignment of the attenuation map and emission image because of respiratory motion causes errors in the attenuation correction factors and artifacts in the attenuation-corrected PET image. To rectify this problem, we evaluated the use of cine CT, which acquires multiple low-dose CT images during a respiratory cycle. We evaluated the average and the intensity-maximum image of cine CT for cardiac PET attenuation correction. METHODS: Cine CT data and cardiac PET data were acquired from a cardiac phantom and from multiple patient studies. The conventional helical CT, cine CT, and PET data of an axially translating phantom were evaluated with and without respiratory motion. For the patient studies, we acquired 2 cine CT studies for each PET acquisition in a rest-stress (13)N-ammonia protocol. Three readers visually evaluated the alignment of 74 attenuation image sets versus the corresponding emission image and determined whether the alignment provided acceptable or unacceptable attenuation-corrected PET images. RESULTS: In the phantom study, the attenuation correction from helical CT caused a major artifactual defect in the lateral wall on the PET image. The attenuation correction from the average and from the intensity-maximum cine CT images reduced the defect by 20% and 60%, respectively. In the patient studies, 77% of the cases using the average of the cine CT images had acceptable alignment and 88% of the cases using the intensity maximum of the cine CT images had acceptable alignment. CONCLUSION: Cine CT offers an alternative to helical CT for compensating for respiratory motion in the attenuation correction of cardiac PET studies. Phantom studies suggest that the average and the intensity maximum of the cine CT images can reduce potential respiration-induced misalignment errors in attenuation correction. Patient studies reveal that cine CT provides acceptable alignment in most cases and suggest that the intensity-maximum cine image offers a more robust alternative to the average cine image.     

Predictors of surgical wound infection in Australia: a national study

In July 1984, the first national Australian Nosocomial Prevalence Survey collected data on 12,742 surgical patients from 265 hospitals. This sample represented 59% of public and private hospitals with 50 or more acute-care beds in Australia. The infection control officers at each hospital provided data on patients in a random sample of beds. The over-all surgical wound infection rate was 4.6%. The surgical wound infection rate was twice (5.4%) as high in public than in private (2.8%) hospitals. The infection rates were greater in larger hospitals in both the public and private sector. However, after adjusting for the other predictor factors that are noted below the infection rate did not show any particular pattern for the size of hospital. Clean surgery had a higher (4.8%) infection rate than did clean-contaminated surgery (2.9%). The infection rate for contaminated surgery was 15.0%. Men were found to have nearly twice (6.5%) the infection rate of women (3.4%). Infection rates were lowest in the 15-to-34 years' age-group and highest in those of over 55 years of age. These trends remained even after adjusting for the other risk factors for infection. The cost of surgical wound infections for all hospitals during the year of 1984 was estimated at approximately $60 million. We suggest that a concerted effort should be made to attempt to reduce the infection rate for clean surgery to 1% or less.     

Chronic Ethanol Inhibits Inositol Metabolism in Specific Brain Regions

Many neurotransmitters and hormones in the nervous system transmit signals through receptors coupled to the poly-phosphoinositide (PI) signaling pathway. In this study, an in vivo protocol with (³H]inositol was used to examine the effect of chronic ethanol administration on inositol metabolism and poly-PI turnover in the cerebral cortex, hippocampus, and cerebellum of mouse brain. C57BL/6 mice were given a nutritionally complete liquid diet containing either ethanol (5%, w/v) or isocaloric sucrose for 2 months. Mice were injected intracerebrally with ^rH]inositol; after 16 or 24 hr, they were injected intraperitoneally with lithium (8 mEq/kg body weight) to inhibit the inositol monophosphatase (IP₁) activity. All mice were decapitated 4 hr after lithium injection. Labeled inositol phospholipids accounted for 16 to 23% of total labeled inositol in different regions of control mouse brain, and the percentages in the hippocampus were consistently higher than the cerebral cortex and cerebellum. In control mice, the percentages of labeled IP, after a 4-hr lithium treatment were 11.5%, 9.9%, and 3.7% for cerebral cortex, hippocampus, and cerebellum, respectively. Chronic ethanol feeding resulted in a significant (p < 0.05) decrease in the percent of labeled IP₁ and inositol phospholipids, and this effect was observed in the cerebral cortex and, to a lesser extent, hippocampus but not cerebellum. When ratios of labeled IP₁ were expressed against labeled inositol phospholipids as an index of the poly-PI turnover activity, significant decreases in IP/lipid ratios were observed in the cerebral cortex, but not the hippocampus or cerebellum. Although mice killed 24 + 4 hr after the last ethanol feeding would have experienced an 8-hr period of ethanol withdrawal, compared with the 16 + 4-hr group, no differences in IP/lipid ratios were observed between the two time groups. These results illustrate regional differences in the effect of chronic ethanol on inositol metabolism in the brain, but no difference in poly-PI turnover in brain due to ethanol withdrawal.     

The pharmacokinetics of isoxicam in elderly patients with rheumatoid arthritis

Nineteen patients, aged 60 years and over, with rheumatoid arthritis participated in a clinical trial to investigate the pharmacokinetics of isoxicam (a new non-steroidal anti-inflammatory drug) in this age group. The purpose of the study was to determine if the pharmacokinetics are different compared to a younger healthy population. The half-lives were independent of dosage, indicating linearity of pharmacokinetics. Furthermore, the half-lives after repeated dosing were not different from those found after single doses of 400 mg. This shows that there is neither undue accumulation of the drug nor induction of its own metabolism. These results are similar to the results obtained in other centres when isoxicam was administered to healthy subjects between 18 and 32 years.     

Meningioma of the floor of the anterior cranial fossa with bilateral intraorbital extension

We report meningioma of the floor of the anterior cranial fossa with bilateral, symmetrical intraorbital extension, describing the findings on plain films and CT.