Brain parenchymal infection in bone marrow transplantation patients: CT and MR findings.

OBJECTIVE: The purpose of this study was to assess the MR and CT appearance of brain infection after bone marrow transplantation and to correlate the appearances with laboratory and pathologic findings. MATERIALS AND METHODS: We retrospectively reviewed the records of seven bone marrow transplant recipients with radiologic evidence of brain infection. RESULTS: Forty-one lesions were detected in seven patients with proved infectious foci outside the brain before brain infection was suspected clinically. Six patients had low total WBC or lymphocyte counts and one patient had normal total WBC and lymphocyte counts. Most lesions in patients with low total WBC or lymphocyte counts showed no appreciable edema or contrast enhancement. However, all lesions detected in the patient with normal total WBC and lymphocyte counts showed marked vasogenic edema and ring enhancement. CONCLUSION: Brain infection in bone marrow transplant recipients during immunosuppression exhibited MR characteristics different from those typically seen in immunocompetent patients. This appearance may be related to a diminished immunologic/inflammatory response.

Treating oral sarcoidosis.

Oral sarcoidosis is rare and can be confused with various other lesions. Two case reports of sarcoidosis involving the lips are presented along with a discussion of sarcoidosis and treatment options.

Arterial enhancement in acute cerebral ischemia: clinical and angiographic correlation.

PURPOSE: To investigate the cause and clinical significance of arterial enhancement (AE) in contrast-enhanced T1-weighted MR examinations after acute cerebral ischemia. METHODS: Contrast MR examinations and conventional angiograms of 17 patients studied following an acute ischemic event or an internal carotid occlusion were retrospectively reviewed. MR and angiographic studies were performed within 1 day of each other. The presence of AE was correlated with both angiographic findings and patient clinical status. RESULTS: AE was not confined to patients with angiographic evidence of complete arterial occlusion. Only 64% of patients demonstrating AE had complete occlusion angiographically. Complete arterial occlusion did not always correlate with AE. In two of nine patients with complete occlusion, no AE was identified. In five of 10 patients with AE, angiographic slow flow was identified. In patients without AE, no angiographic slow flow was identified. In the 64% of patients with AE, significant symptoms were identified. Patients without AE were either asymptomatic or had mild symptoms at the time of the MR study. CONCLUSIONS: Our data support the hypothesis that arterial slowing is the cause of AE, which appears to be an indicator of decreased brain perfusion. Such MR findings may add important supplemental information to those provided by conventional angiography.

MRI spectrum of medulloblastoma.

Medulloblastomas have been characterized as solid, homogeneously enhancing, midline masses of the posterior fossa. To evaluate atypical MRI characteristics, we retrospectively reviewed 13 histologically proven medulloblastomas. MRI examinations were correlated with pathologic specimens and operative reports. Atypical features included cyst formation (77%), irregular enhancement (19%), extension through fourth ventricle foramina (15%), and presentation as a cerebellopontine angle mass (8%). We conclude that "atypical" characteristics are common. In the child or young adult, medulloblastomas must be included in the differential diagnosis of any posterior fissa mass.

Gadolinium-enhanced MR of the postoperative internal auditory canal following acoustic neuroma resection via the middle fossa approach.

PURPOSE: To evaluate the ability of gadolinium-enhanced MR in detecting recurrent tumor in patients whose acoustic neuromas were surgically removed via the middle cranial fossa approach. PATIENTS AND METHODS: Postoperative gadolinium-enhanced exams of 13 of 44 patients who underwent excision of acoustic neuromas via the middle cranial fossa approach were reviewed. RESULTS: Postoperative enhancement was seen in 12 of the 13 patients; two patients underwent serial exams without significant change. On the basis of a single exam, we were unable to conclusively differentiate postoperative enhancement from residual or recurrent tumor. CONCLUSIONS: A single exam is of limited value. Serial studies are recommended to identify changes that would indicate tumor growth. A proposed MR follow-up schedule is an initial baseline exam within 2 months of surgery and a repeat exam during the second postoperative year.

Older volunteers: a discussion of the Minnesota Senior Study.

We used findings from the Minnesota Senior Study to examine the theoretical and methodological difficulties of defining, coding, and analyzing data on older volunteers. This study, the first statewide survey of the needs and resources of the elderly in Minnesota in almost 20 years, found that over half (52%) of older Minnesotans do volunteer work for organizations--considerably higher than has been found in national surveys. Problems in definition and methodology, however, have confounded analyses. This paper proposes a new conceptual model for classifying volunteer roles, based on three dimensions: whether the voluntary service is "formal" or "informal"; whether the activity entails a regular or an occasional time commitment; and the nature of the service activity (person-to-community, person-to-object, or person-to-person).

Temporal bone computed tomography in the preoperative evaluation for cochlear implantation.

High resolution computed tomography of the temporal bone is performed routinely in the preoperative evaluation for cochlear implantation. A retrospective review was performed to determine the effect of these studies. The clinical significance was determined through consultation with the referring otolaryngologist and review of the operative reports. Twelve examinations were reviewed. Abnormalities were identified in 12 of the 24 ears examined (eight of 12 patients studied). In two patients the CT examination strongly influenced the selection of the ear to be implanted. In four additional cases information felt to be useful in preoperative planning was provided. Useful information related to potential complications with the mechanical insertion of the electrode apparatus. We conclude that temporal bone abnormalities are common in the population undergoing cochlear implantation and that high resolution temporal bone CT is essential in preoperative evaluation. The CT scan should be interpreted with adequate knowledge of the operative procedure to evaluate any possible barriers to the mechanical insertion of the internal components of the system.

Therapists' perceptions of difficult psychiatric patients.

Psychotherapists often describe patients who present management problems as "difficult patients." This article describes a 5-factor scale to measure how therapists perceive difficult psychiatric patients. Reliability and validity evidence is presented for scales labeled Demanding, Help Rejecting, Unreachable, Dangerous, and Poor Fit. Fifty-four psychiatric outpatients identified as difficult to treat by two or more therapists were compared with 54 control psychiatric outpatients matched on age, sex, marital status, and diagnosis. Therapists rated difficult patients higher on each scale. Patients rated higher on the Demanding, Help Rejecting, and Poor Fit scales were heavier and more varied users of the treatment system than were those rated lower on these scales. The scale helps identify causes of staff dissatisfaction and inappropriate organization of services and suggests how to meet the special needs of difficult patients. Problem patients can be seen as denying the competence and authority of the mental health professional but also as central to the unique mandate of psychiatry. The reward system should more adequately support those therapists who care for the patients often avoided by others.

The current status of urban-rural differences in psychiatric disorder. An emerging trend for depression.

Evidence for differences in rates of psychiatric disorder by size of community is examined. Epidemiological studies reporting rates for specific diagnoses (treated and untreated) as well as those making only global assessments of psychiatric caseness are examined. An interesting trend toward higher rates of depressive disorders (excluding manic-depressive psychosis) in urban areas emerges. Differences in the availability of social support in communities in varying size is proposed as a possible explanation for this finding.