The value of performing cerebrovascular CT angiography in major trauma patients: a 5-year retrospective review.

AIM: To assess whether routine cerebrovascular imaging is required in all major trauma (MT) patients. MATERIALS AND METHODS: All MT patients with cerebrovascular imaging between January 2015 and December 2020 were included in the study. Data were collated regarding the type of indication for computed tomography (CT) angiography imaging, time interval from the initial trauma, relevant trauma diagnoses on initial trauma imaging, and CT angiography. Findings, such as aneurysms, vascular malformations, luminal thrombus, venous sinus thrombosis, or vascular injury, were collated. Subsequent treatment with anti-coagulants/anti-platelets or surgical/radiological intervention was noted. Follow-up imaging was assessed for residual injury or complications. RESULTS: Two hundred and fifty of the 6,251 MT patients underwent dedicated cerebrovascular imaging and were included in the study. Of these 41 (16.4%) had cervical artery or venous sinus injury. Further positive vascular findings were identified in 25/250 patients who presented with an incidental stroke or a vascular abnormality and were mislabelled as MT patients at presentation. One patient with a carotid injury subsequently died following a large infarction. Another patient with vertebral artery injury suffered a non-lethal stroke. No patients underwent surgery or intervention. CONCLUSION: The present study showed that the overall incidence of detected blunt cerebrovascular injuries was very low (0.6%) and even lower for symptomatic vascular injury (0.03%). Routine cerebrovascular imaging is not recommended in all MT trauma patients, but instead, a continued case-by-case basis should be considered.

Polioencephalomalacia (cerebrocortical necrosis) induced by experimental thiamine deficiency in lambs.

Lesions of polioencephalomalacia (PEM, cerebrocortical necrosis) have been demonstrated in pre-ruminant lambs fed on synthetic, thiamine-free milk. Thiamine deficiency in these lambs was confirmed by transketolase assay.

Induced thiamin deficiency in lambs.

By following a feeding regimen which consistently induced polioencephalomalacia in pre-ruminant lambs it was possible to study certain characteristics just before the terminal stage in polioencephalomalacia. There was always a marked deficit in erythrocyte precursors in bone marrow and this preceded any pathological changes in the brain. Erythrocyte transketolase activity decreased in control lambs, and decreased to an even greater extent in thiamin-deficient lambs. Glucose was the only substrate of those measured which was used by the brain, and its rate of use was not affected by thiamin deficiency. After a single intravenous injection of 35S-thiamin, the decrease of 35S in the plasma was consistent with its dispersal into two pools: the half-time of disappearance of 35S into the slowly equilibrating pool was less in thiamin-deficient lambs than in their controls. Characteristics which were not altered in thiamin deficiency were concentrations of calcium and magnesium in various regions of brain and concentrations of calcium, magnesium, sodium and potassium in plasma.

Thiamin deficiency in the lamb: changes in thiamin phosphate esters in the brain.

Concentration of thiamin (unphosphorylated), thiamin monophosphate (TMP), thiamin diphosphate (TDP), and thiamin triphosphate (TTP) were measured in three regions of the brain of seven pairs of lambs. The lambs were maintained on a thiamin-free synthetic diet for 2, 3, or 4 weeks. Controls were pair-fed and supplemented with thiamin. The three brain regions were: (1) dorso-lateral aspect of the cortex [common site for lesions of polioencephalomalacia (PEM)]; (2) pyriform lobe of the cortex (no PEM lesions are found here); (3) white matter of the internal capsule (no PEM lesions found here). The concentration of TTP ina ll three sections of brain was maintained at control values for up to 4 weeks on the thiamin-deficient diet. TDP concentration decreased to 22% of control values in both regions of grey matter after 4 weeks on the diet. Unphosphorylated thiamin and TMP decreased to a smaller extent than TDP.

Thiamin inadequacy in infants: lack of evidence of amprolium in egg yolk.

This study investigated the hypothesis that the consumption of egg yolks might lead to thiamin inadequacy in infants because of the possible contamination of the egg yolks with amprolium. Earlier workers showed that the presence of amprolium in the diet inhibits the absorption of thiamin. Amprolium is added to some poultry feeds to control coccidiosis: it is readily incorporated in the egg yolk and egg yolk is one of the solid foods offered to infants at weaning. We found that under current commercial poultry feeding practices in WA it is extremely unlikely that any amprolium would be present in commercial eggs or poultry. Amprolium was undetectable in eggs purchased at several retail outlets. Thus there is no evidence that consumption of egg yolk contributes to thiamin inadequacy in infants.

Composition and protein quality of honeybee-collected pollen of Eucalyptus marginata and Eucalyptus calophylla.

The composition and protein quality of the two most important Western Australian export-quality pollens were investigated. Crude pollen protein content was 20.6% and 27.9% for Jarrah (Eucalyptus marginata) and Marri (Eucalyptus calophylla), respectively. Lysine was the limiting amino acid relative to the FAO protein scoring pattern (Food and Agriculture Organization of the United Nations), and the amino acid scores were 0.73 and 0.66 for Jarrah and Marri pollen, respectively. Apparent biological value (BV) was 61.7 for Jarrah pollen, 66.9 for Marri pollen and 71.4 for the casein controls. Adjusted protein efficiency ratio (PER) values were 2.5, 1.2 and 1.1 for casein and Jarrah and Marri pollens, respectively. Apparent net protein utilization (NPU) was significantly reduced for both pollens (32.8 for Jarrah and 39.5 for Marri) compared to casein (63.6). The low apparent NPU values result from the relatively low digestibility of pollens. Apparent digestibility was 52 and 59% for Jarrah and Marri pollen compared to 89% for casein. Although both Jarrah and Marri pollen are relatively high in protein and have favorable amino acid patterns, their relatively low digestibility will be a limiting factor in their usefulness as a food for humans and monogastric animals. The proximate analysis and mineral content of the pollens are also presented.