qMRI relaxometry of mandibular bone marrow: A monomodal distribution in sickle cell disease

Purpose:

To identify and characterize sickle cell disease (SCD)‐related changes in the composition of mandibular bone marrow using qMRI relaxometry histograms.

Materials and Methods:

Thirteen SCD patients and 17 controls underwent brain MR imaging with the mixed turbo spin‐echo (TSE) pulse sequence at 1.5T. The mandible was manually segmented and divided into body, angle, ramus, and condyle. T1 and T2 histograms of each mandible were modeled with Gaussian functions. The relaxation time histogram peaks were calculated, and the number of monomodal versus bimodal curves was compared.

Results:

SCD patients exhibited monomodal distributions on both T1 and T2 histograms, consistent with a composition of predominantly red hematopoietic marrow. Eighty‐eight percent of mandibles in control subjects exhibited a bimodal distribution in T1 and all showed a bimodal distribution in T2, indicating mixed but predominantly yellow marrow composition. The second peak in control subjects was shorter in T1 and longer in T2, consistent with yellow marrow composition.

Conclusion:

Instead of physiological fatty replacement, SCD patients exhibit red marrow persistence in the mandible, likely due to the increased demand for hematopoiesis. This phenomenon can be manifested by a monomodal curve in both T1 and T2 relaxometric histograms. J. Magn. Reson. Imaging 2013;37:1182–1188. © 2012 Wiley Periodicals, Inc.     

Influence of Race and Geographical Origin on Sarcoidosis

Veterans hospitalized with sarcoidosis from 1958 to 1964 were analyzed with respect to their birthplace and the 1930 population census of the various states. In every region, the rate of sarcoidosis was 12 to 15 times higher in Negroes than in whites. Differences among the various geographical areas were insignificant.     

The 16 golden hours for conservative treatment in children with postoperative small bowel obstruction

Background

Conservative treatment of postoperative small bowel obstruction in children is widely accepted, provided that there are no clinical signs of bowel strangulation. However, the length of time surgery can be safely deferred remains unclear.

Purpose

The aim of this study was to determine the time limit for observant management of postoperative small bowel obstruction.

Methods

The medical records of 128 children with 174 episodes of postoperative small bowel obstruction were reviewed.

Results

Spontaneous resolution occurred in 63% of cases, 85% within 48 hours of admission. Bowel compromise was noted in 31% of the operated cases, and about half of them underwent bowel resection, accounting for 6% of all admissions. None of the cases treated surgically within 16 hours of admission was associated with bowel strangulation or need for resection.

Conclusions

In children presenting with postoperative small bowel obstruction, prolonging observant treatment for more than 48 hours yields only a small benefit in terms of spontaneous resolution. Bowel strangulation can occur within 16 hours of admission. On the basis of these findings, we suggest raising the index of suspicion for compromised bowel after 16 hours and making the decision for surgery at around 48 hours.     

Comparison of three rating scales as outcome measures for treatment trials of depression in Alzheimer disease: findings from DIADS

CONTEXT: Major depression affects about 25% of patients with Alzheimer's disease (AD) and has serious adverse consequences for patients as well as caregivers. Studies of treatments for depression in AD, like most treatment studies, depend on the ability of the scales used to measure outcome to detect a difference between the effects of treatment and control, particularly in trials conducted over waves. OBJECTIVE: To compare the ability of three depression scales, and some of their subscales, to detect the difference in the effects of drug (treatment) and placebo (control). DESIGN: Comparison of three scales of depression in terms of percent variance explained as indicated by the adjusted or partial eta-squared for the effect of drug versus placebo, controlling for baseline depression, in a randomized, placebo-controlled, parallel, 12-week, clinical trial of sertraline for the treatment of depression with AD. SETTING: University outpatient clinic. PARTICIPANTS: Forty-four patients with probable Alzheimer's disease and Major Depressive Episode. OUTCOME MEASURES: The Cornell Scale for Depression in Dementia (CSDD), the Hamilton Depression Rating Scale (HDRS), and the Neuropsychiatric-Inventory Mood Domains (NPI-M). RESULTS: Examination of the treatment effects as indicated by the partial eta-squared's for each scale at each wave, revealed a slight, but not significant, advantage for the use of the CSDD over the HDRS, and a significant advantage for the use of either of these over the NPI-M. Treatment effects, as reflected in the partial eta-squared's computed for the subscales at each wave, were significant for all four subscales, and were largest for the CSDD 'mood' subscale although they were not significantly greater than for the other subscales. CONCLUSIONS: The CSDD, and particularly its mood subscale, appears to be more sensitive than the HDRS, it's subscales or the NPI-M, for comparing drug to placebo in treating major depression in AD patients. Treatment effects as reflected in the partial eta-squared's were largest on the CSDD mood subscale and increased over time. The pattern for the other subscales was non-monotonic over waves and resembled the pattern for the entire scale. Perhaps combining the CSDD two subscales obscures the treatment effects for the separate subscales.     

Sleep, sleepiness, and behavior problems in children with headache

The purpose of this study was to assess sleep, daytime sleepiness, and behavior problems in children suffering from headaches and in controls, with a special focus on the role of gender. A clinical group of 28 children with persistent headache complaints and a control group of 108 healthy children were included. Sleep was assessed by actigraphy and diaries. Behavior problems were assessed by parental reports. In comparison with the control group, the sleep quality of the clinical group was poorer and they complained more about excessive daytime sleepiness. Children suffering from headache showed higher levels of internalizing behavior problems. Gender was found to be a moderating factor for the relationships between headache and sleep. Compared with control girls, girls suffering from headaches had poorer sleep quality, whereas the opposite was true for the boys. The results highlight the importance of assessing sleep, daytime sleepiness, and psychologic adjustment in children complaining about headaches as an integral part of their routine assessment.     

Hodgkin disease: prediction of outcome with 67Ga scintigraphy after one cycle of chemotherapy

PURPOSE: To investigate gallium 67 scintigraphy performed early during treatment as a means to predict outcome and thus to optimize treatment of Hodgkin disease (HD) in the future. MATERIALS AND METHODS: Ninety-eight patients with HD were examined. Thirty-one patients underwent 67Ga scintigraphy after one chemotherapy cycle and 83 patients after a mean 3.5 cycles (range, 2-5 cycles). Sixteen patients underwent 67Ga scintigraphy both after one cycle and at midtreatment. Patients underwent whole-body scintigraphy and single photon emission computed tomography of the torso. Torso computed tomography (CT) was performed after a mean 3.5 cycles (range, 2-6 cycles). Failure-free survival was compared between patients with positive and patients with negative test findings (Kaplan-Meier method), and the significance of the difference was calculated. The association of failure-free survival with various prognostic clinical factors before treatment was compared (log-rank test univariate analysis). RESULTS: Failure-free survival differed significantly (P < .002) between patients with positive and patients with negative 67Ga scintigrams after one chemotherapy cycle but not at midtreatment. Failure-free survival was not significantly different between patients with positive and patients with negative CT scans at midtreatment. Twenty-two (92%) of 24 patients with negative 67Ga scintigrams after one cycle and 64 (82%) of 78 patients with negative scintigrams at midtreatment remained in complete response. In four (57%) of seven patients with positive 67Ga scintigrams after one cycle, treatment failed. CONCLUSION: 67Ga scintigraphy after one cycle of chemotherapy is a good early predictor of outcome of HD.     

Visual validation of the mechanical stabilizing effects of positive end-expiratory pressure at the alveolar level

BACKGROUND: Positive end-expiratory pressure (PEEP) reduces ventilator-induced lung injury (VILI), presumably by mechanically stabilizing alveoli and decreasing intrapulmonary shear. Although there is indirect support for this concept in the literature, direct evidence is lacking. In a surfactant depletion model of acute lung injury we observed unstable alveolar mechanics referred to as repeated alveolar collapse and expansion (RACE) as measured by changes in alveolar area from inspiration to expiration (I - E(Delta)). We tested the hypothesis that over a range of tidal volumes PEEP would prevent RACE by mechanically stabilizing alveoli. MATERIALS AND METHODS: Yorkshire pigs were randomized to three groups: control (n = 4), Tween (surfactant-deactivating detergent) (n = 4), and Tween + PEEP (7 cm H(2)O) (n = 4). Using in vivo video microscopy individual alveolar areas were measured with computer image analysis at end inspiration and expiration over consecutive increases in tidal volume (7, 10, 15, 20, and 30 cc/kg.) I - E(Delta) was calculated for each alveolus. RESULTS: Surfactant deactivation significantly increased I - E(Delta) at every tidal volume compared to controls (P < 0.05). PEEP prevented this change, returning I - E(Delta) to control levels over a spectrum of tidal volumes. CONCLUSIONS: RACE occurs in our surfactant deactivation model of acute lung injury. PEEP mechanically stabilizes alveoli and prevents RACE over a range of tidal volumes. This is the first study to visually document the existence of RACE and the mechanical stabilizing effects of PEEP at the alveolar level. The ability of PEEP to stabilize alveoli and reduce shear during mechanical ventilation has important implications for therapeutic strategies directed at VILI and acute respiratory distress syndrome.