Problem based learning at medical school. Some people think it's thrilling...
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to R Farrow.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Air has been traditionally used as the negative contrast agent in double contrast barium enema (DCBE) examinations, but causes abdominal pain in the 24 h following the procedure. The frequency of post-procedural pain is less when carbon dioxide (CO2) is used as the negative contrast agent. We evaluated patients following DCBE examinations (using either air or CO2) by means of a questionnaire, to determine whether active drainage of gas altered the post-procedural pain. There was no difference in the pain experienced in the groups receiving CO2 with either active or passive drainage, or in the group receiving air with active drainage. Compared with the other groups there was a significantly higher incidence and severity of pain in the group receiving air and passive drainage. We conclude that active drainage of air following a DCBE examination is as effective as using CO2 in reducing post-procedural pain and swelling.
Recently, focal fat collections adjacent to the intrahepatic portion of the inferior vena cava (IVC) have been described as a normal variant. We present seven similar cases, and demonstrate the computed tomographic and sonographic findings. The differential diagnosis is discussed. We believe that the origin of these masses has not yet been satisfactorily proven, and that they may arise within the IVC. They appear to be benign, but there is a risk that they may be mistaken for more sinister pathology.
Eight cases of aortic dissection with atypical CT appearances are described. Seven were clinical diagnoses, one was confirmed at operation. The findings were those of intramural haematoma, often crescentic and not necessarily compressing the aortic lumen. Evidence is presented to show that some intramural haematomas may subsequently develop ulceration, resulting in the appearances described in penetrating atheromatous ulcer of the aorta.
Explore the source record for details and available documents.
RATIONALE AND OBJECTIVES: Studies describing the effects of radiographic contrast media (RCM) in leukocyte chemotaxis have been contradictory. No studies have been performed after in-vivo exposure. The authors assess the effect of RCM on leukocytes following in-vivo exposure. METHODS: Seventeen patients were studied after intraarterial bolus injection of 75 mL of iohexol (300 mg/mL) or iotrolan (300 mg/mL), 30 minutes and 24 hours postinjection; chemotaxis was assessed using an ex-vivo whole-blood under-agarose method. RESULTS: With iohexol, there was a profound reduction in chemotaxis compared with the preinjection state (P = .001) at 30 minutes. No effect, however, was seen at 24 hours. With iotrolan, no significant reduction in chemotaxis was seen at 30 minutes or at 24 hours. CONCLUSIONS: Radiographic contrast media have differing effects on leukocyte chemotaxis. This may be of significance in the selection of appropriate RCM in certain patients.
The effects of radiographic contrast media (RCM) on leucocyte orientation in vitro were studied using a Zigmond chamber. Leucocyte orientation was assessed following exposure of the leucocytes to iotrolan, iohexol, ioxaglate and diatrizoate. The RCM used were diluted to a concentration similar to that obtained in vivo during routine angiography. At this concentration there was a significant reduction in leucocyte orientation for all RCM investigated but the effect was more pronounced in the monomeric than the dimeric RCM. The results may have significance when deciding which radiographic contrast medium to use in selected patients, particularly those who are immunosuppressed or septicaemic.
A 54-year-old woman with unoperated patent ductus arteriosus developed fatal cardiac tamponade due to a dissecting aneurysm of the pulmonary artery causing haemopericardium. Histology of the pulmonary artery showed the presence of cystic medial necrosis. Previous reports of this condition are reviewed and the role of pulmonary hypertension causing secondary cystic medial necrosis is discussed.
Phaeochromocytoma is rare and usually presents as paroxysmal or sustained hypertension; none the less, it can also cause severe acute pulmonary oedema in normotensive individuals. Six patients with phaeochromocytoma presenting in Cornwall and West Devon between 1982 and 1986 are described. Five of them died of pulmonary oedema within 24 hours of the onset of symptoms. At necropsy all five had normal sized hearts and in the four hearts examined by histology there was evidence of catecholamine induced heart disease in the form of focal myocardial necrosis. The sixth patient presented with arterial spasms and pulmonary oedema. Surgical removal of the causative tumour was successful in this patient.
Non-saponifiable cell extracts of wild type and sterol mutants of N. crassa were analysed by means of gas-liquid chromatography. The wild-type contained ergosterol and episertol in a 10:1 ratio. None of the mutants was able to synthesize ergosterol. Three of the mutants carry single recessive gene mutations cauisng blocks in the terminal steps of ergosterol biosynthesis: erg-1 has an inactive delta 8 leads to delta 7 isomerase erg-2 has an inactive 24(28) hydrogenase, and erg-4 has an inactive C-24 methyl transferase. Some of the mutants accumulated novel sterols as a result of their enzyme defects. The genes erg-1 and erg-2 were mapped close to inl on the right arm of chromosome V.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Magnetic resonance (MR) imaging has proved useful in the evaluation of perianal and perirectal lesions resulting from Crohn disease. On T1-weighted MR images, sinus tracts and fistulas are hypointense due to their fluid content; on T2-weighted images, their signal intensity depends on their fluid content and the degree of surrounding fibrosis. Other pathologic entities, such as abscesses in the ischioanal fossa, may become evident at MR imaging even though they remain hidden at digital examination. Rectal wall thickening and perirectal inflammatory changes are often seen at MR imaging of the pelvis. The multiplanar capability of MR imaging greatly facilitates the detection of fistulous tracts that extend into the supralevator space. MR imaging can be helpful to both the surgeon and the gastroenterologist in the assessment of perianal and perirectal complications arising from Crohn disease and, when necessary, in the planning of surgical intervention. MR imaging also recommends itself to the patient because it is noninvasive and does not cause discomfort.