Real‐time RF pulse adjustment for B0 drift correction

Although the magnetic field of an MR scanner is very stable under little or no load, it can become less stable under heavy‐duty cycle conditions, such as in diffusion tensor imaging (DTI). Uncorrected, such field drifts lead to an apparent image shift along the phase‐encoding direction and decreasing effectiveness of fat saturation pulses. A method is presented to adjust the center frequency of all RF pulses and the receiver in real time during the acquisition. No data postprocessing or changes to the sequence timing are necessary. In vivo acquisitions were performed to assess the prolonged effectiveness of fat saturation. Field drifts of approximately 2.5 Hz/min were measured and corrected during DTI acquisitions at b‐values of up to 3000 s/mm². The effectiveness of fat saturation diminished over the duration of an 18‐min acquisition when the drift was left uncorrected. The proposed method corrects for apparent image shift and ensures continuously effective fat saturation over the duration of an acquisition. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.     

The relationship of scoring systems and mortality in the surgical intensive care unit

To determine the relationship between severity of illness and mortality, therapeutic intervention score (TISS) and acute physiology score (APS) were determined on admission to the Surgical Intensive Care Unit (SICU). Patients were divided into survivors and nonsurvivors and differences were compared by chi-square analysis. The 1524 patients admitted to the SICU during a 12-month period had a mean TISS of 3.03 and a mean APS of 13. The average length of stay (LOS) was 3.75 days. Of the 1524 patients, 97 (6.4%) died. The number of nonsurvivors increased with higher TISS and APS scores (P less than 0.001). There were no deaths in the TISS Category 1 patients or in the APS 0-5 group. Mortality rates dramatically increased with APS greater than 20 (P less than 0.001). There were 1286 patients with APS less than 20, and 24 (2%) of these patients died, whereas 73 (31%) of 238 patients with APS greater than 20 died. Nonsurvivors had a mean TISS of 3.6, mean APS of 27, and LOS of 4.88 days, all of which totals were higher than the survivors' totals. In this study population, risk of death was one in three if the APS was greater than 20. These data indicate that TISS and APS scores are effective means of assessing mortality risk in SICU patients.     

Smoking and coffee intake following alcohol withdrawal in alcoholic inpatients

The aim of this study was to assess alcoholic inpatients' smoking and coffee intake variation following withdrawal. Only moderate smokers (less than 30 cigarettes/day) showed a significant increase of cigarette consumption after alcohol withdrawal. However, their urinary cotinine level did not vary, suggesting a behavioral, and not biological, compensation through smoking following alcohol withdrawal. Heavy smokers (30 cigarettes/day or more) showed no significant clinical or biological variation of smoking behavior. Coffee consumption increased after alcohol withdrawal in all patients, irrespective of smoking habits.     

Innovative Laboratory Techniques to Facilitate Processing of Large Mohs Cases

Background Processing multiple tissue sections in large Mohs cases is time consuming and labor intensive.
Objective To present innovative laboratory techniques to facilitate processing of large Mohs cases.
Methods A method for processing a large dermatofibrosarcoma protuberans Mohs case is outlined.
Results Modifications in tissue processing and equipment employed in a large Mohs case are presented.
Conclusion Innovative modifications to the standard Mohs laboratory technique can facilitate processing of large Mohs cases, resulting in high-quality, rapid frozen sections while optimizing efficiency.     

Contrast agents in functional MR imaging

Contrast agents have greatly expanded the role of MR imaging (MRI) to allow assessment of physiologic, or “functional,” parameters. Although activation mapping generally does not require contrast agents, other forms of functional MRI, including mapping of cerebral hemodynamics (eg, perfusion imaging), are best done with the use of contrast agents. Serial echo planar images are obtained after bolus injection of lanthanide chelates. Application of susceptibility contrast physics and standard tracer kinetic principles permits generation of relative cerebral blood volume maps. Deconvolution of cerebral blood flow and mean transit time parameters is also possible within technical limitations. By using diffusion and perfusion pulse sequences, an imaging correlate to the ischemic penumbra can be identified. Functional MRI perfusion imaging of intraaxial tumors is analogous to positron emission tomography for delineation of metabolic activity, yet may be even more sensitive to neovascularity and possesses improved image quality. Clinical applications include biopsy site selection and postirradiation follow-up. Further improvements in data analysis and map generation techniques may improve diagnostic accuracy and utility.     

Bridges and barriers to recovery: Clinical observations from an opiate recovery project

Clinical issues are described in opiate addicts attempting to taper off methadone maintenance, and techniques are suggested to help this patient population. The observations were generated in an experimental “Tapering Network” project, in which opiate addicts on methadone maintenance had the opportunity to receive individual and group counseling, relapse prevention training, self-help groups, and other services. Vignettes illustrate clinical problems with intimacy and social isolation, identity as a former addict, and a “post methadone syndrome” characterized by vulnerability, dramatic swings in mood, and disordered thinking for a period of up to six months after detoxification. To counteract these barriers to recovery, a program model is suggested that uses curricula available in the emerging literature on treatment of substance abuse. These techniques can provide bridges to recovery.     

Inconsistencies in paranoid functioning, premorbid adjustment, and chronicity: question of diagnostic criteria

Despite the widely held belief that paranoid behavior is associated with good premorbid adjustment, low chronicity, and high current functioning in psychiatric inpatients, inconsistencies in the literature suggest that supportive evidence may be an artifact of the measurement model commonly used to index paranoid status. In a sample of 497 nonorganic inpatients selected from 19 treatment units, paranoid behavior, when measured by a dimensional/cumulative model, was not found to indicate higher functioning and associated relationships, but simply to reflect a narrower class of problem behavior. Only when paranoid status was defined using a traditional model based on the predominance of the defining class of behavior did paranoid subjects demonstrate better premorbid adjustment, lower chronicity, and higher levels of functioning than nonparanoid subjects. Serious problems exist in the use of information obtained from traditional predominance/class models for either theoretical or practical purposes.     

Regional Variation in Wound Contraction of Mohs Surgery Defects Allowed to Heal by Second Intention

BACKGROUND: The phenomenon of wound contraction results in a decrease in wound size and a healed scar significantly smaller than the original defect. OBJECTIVE: This study was undertaken (1) to determine the amount of wound contraction in Mohs surgery defects allowed to heal by second intention, (2) to evaluate for regional differences in wound contraction based on the facial anatomic zones for second intention healing described by Zitelli, and (3) to determine whether regional differences in wound contraction account for observed differences in cosmetic outcome. METHODS: One hundred sixty secondarily healed Mohs surgery defects limited to the head and neck having a wound age of greater than 12 weeks in 102 consecutively examined patients were carefully measured with a tissue caliper. The percent wound contraction was calculated and compared for each Zitelli anatomic subunit. The final shape of the wound (quantitatively described) and the cosmetic acceptability (subjectively rated by the patient and examiner) were also compared with the percent wound contraction for each anatomic area. RESULTS: Both NEET (concave surface of the nose, eye, ear, and temple) and FAIR (forehead, antihelix, eyelids, and the remainder of the nose, lips, and cheeks) areas were identical in terms of mean wound contraction (74%), cosmetic acceptability (97%), and conversion to a wound shape with a ratio of maximal length to width of greater than 3.0 (fusiform and linear shapes) (52%). NOCH areas (convex surface of the nose, oral lips, cheeks and chin, and the helix of the ear) demonstrated less wound contraction (66%), cosmetic acceptability (78%), and fusiform-linear conversion (29%). Subset differences and variables that appear to influence wound contraction are discussed. Secondarily healed wounds in areas with one or more positive contraction variables contract 75%, whereas defects in areas with negative contraction variables contract 55%. CONCLUSIONS: Regional differences in wound contraction of secondarily healed head and neck wounds exist and account for some differences in cosmetic acceptability. Scar location, regardless of the degree of wound contraction, is the most important factor for the final cosmetic outcome.