Obstructive sleep apnea: diagnosis with ultrafast CT

Patients with sleep-disordered breathing often have physiologic and anatomic abnormalities of the upper airway that are demonstrable while awake. An ultrafast computed tomographic (CT) scanner was used to measure the oropharyngeal and nasopharyngeal cross-sectional areas of 11 patients with obstructive sleep apnea. Twenty-four healthy volunteers served as control subjects. The percentage of change in cross-sectional area during quiet tidal breathing was used as a measure of airway compliance. Compared with weight-matched control subjects, patients with obstructive sleep apnea had smaller oropharyngeal airways (40.4 vs 177.8 mm2) (P less than .001) and smaller nasopharyngeal airways (31.3 vs 134.2 mm2) (P less than .001). In addition, their oropharyngeal airways were significantly more compliant (75% vs 27%) (P less than .001). Patients with obstructive sleep apnea are characterized by a small, collapsible oropharyngeal airway and by nasopharyngeal airway narrowing. These abnormalities can cause sleep-disordered breathing. Ultrafast CT scanning allows rapid, noninvasive assessment of airway variables.     

Strangulation in child abuse: CT diagnosis

The central nervous system is commonly affected in child abuse. Between April 1985 and July 1986 three infants were identified in whom the primary mode of injury had been strangulation. In each case computed tomography (CT) demonstrated a large cerebral infarction confined to vascular territories associated with small subdural hematomas. There was no history or visible evidence of significant head trauma. Autopsy of one infant confirmed the presence of a hemispheric infarct, thin subdural hematoma, and an area of subintimal hemorrhage in the carotid artery ipsilateral to the infarct. The remaining two patients survived with residual hemiparesis. CT findings of a large cerebral infarction with an associated subdural hematoma in an infant without a history of a significant trauma should suggest the possibility of child abuse and may be the primary manifestation of abuse in some patients.     

A CCl4/CHCl3 Interaction Study in Isolated Hepatocytes: Selection of a Vehicle

Emulphor, ethanol, and dimethyl sulfoxide (DMSO) were evaluatedas vehicles in studying the toxicity of CCl₄ and CHCl₃ in isolatedhepatocytes. The appropriateness of the vehicle was determinedby evaluating the following parameters: solubility of CCl₄ andCHCl₃ in the vehicle, cell injury (intracellular K+), cell death(LDH leakage), and lack of interaction (protection or enhancedtoxicity) with CCl₄. and CHCl₃. The relative toxicity of thevehicles according to maximum no effect levels (v/v) was: emulphor(0.125%) > ethanol (1.0%) > DMSO (5.0%). Emulphor at toxiclevels was inadequate to dissolve enough CCl₄ to evaluate inthis system. Ethanol (5.0, 2.5, 1.0, 0.5%) was more toxic thanDMSO and interacted with both CCl₄. and CHCl₃ to enhance toxicity.DMSO (15.0, 5.0, 2.5%) did not significantly alter the toxicityof CCl₄. and CHCl₃ no interaction. These data suggest that DMSOshould be the vehicle for evaluating the toxicity of CCl₄. andCHCl₃ and their mechanisms of action in the isolated hepatocyte.     

Congestive cardiomyopathy in association with AIDS

During a 10-month period in 1985 and 1986, three cases of acquired immunodeficiency syndrome (AIDS) and a rapidly progressive fatal cardiomyopathy were encountered. All three patients originally presented with common opportunistic infections and later experienced marked congestive heart failure associated with echocardiographic and radiologic findings consistent with four-chamber cardiomyopathy. Diffuse cardiomyopathy was confirmed postmortem, but in each case a specific cause was not found.     

Changes in body temperature and urinary cortisol after routine immunization in babies with intrauterine growth retardation

Aim : To investigate whether infants with intrauterine growth retardation (IUGR) experience different changes in temperature and cortisol excretion after routine immunization compared with normal healthy infants. Methods : Overnight deep body temperature and urinary cortisol to creatinine ratios were measured on the night after immunization and a control night in normal and IUGR infants. Results : In 60 normal infants, first vaccination at about 10 wk of age led to a significant increase in minumum overnight temperature compared to the control night, mean rise 0.25°C (95% CI, 0.12 to 0.38). In 35 IUGR infants the mean rise in temperature between immunization night and control night was 0.35°C (95% CI, 0.15 to 0.55). The increases in minimum temperature did not differ significantly between the normal and IUGR infants ( p = 0.11). Cortisol to creatinine ratios measured from overnight urine samples showed that 23 IUGR infants had consistently higher levels than 39 normal infants; control night medians 34 and 15 ( p = 0.01) and immunization night medians 56 and 26 ( p= 0.02), respectively. However, the percentage increase did not differ significantly between the IUGR infants and the normal infants. A smaller number of second immunizations were studied, but no significant differences were found.

Conclusion : These results suggest that although the impact of immunization is the same for IUGR and normal infants, because IUGR infants are less mature and at greater stress before immunization, the absolute levels that they experience after immunization are higher than those for normal infants.