Postinflammatory ossicular fixation: CT analysis with surgical correlation

Postinflammatory ossicular fixation is a common problem encountered by the otologic surgeon upon exploration because of conductive hearing loss in patients with chronic otitis media. These nonotosclerotic noncongenital lesions take three pathologic forms: fibrous tissue fixation (chronic adhesive otitis media), hyalinization of collagen (tympanosclerosis), and new bone formation (fibro-osseous sclerosis). Fibrous tissue fixation appears on CT as nonbony, noncalcific soft-tissue debris encasing some or all of the ossicular chain. Tympanosclerosis appears as unifocal or multifocal punctate or weblike calcifications in the middle ear cavity or on the tympanic membrane. This debris may be in direct apposition to the ossicular chain or may replace the suspensory ligaments in symptomatic patients. New bone formation has been identified only in the attic and is the least common manifestation. Thick bony webs or generalized bony encasement may be present at CT. More than 300 patients with the clinical diagnosis of chronic otitis media have been examined. This study encompasses 23 proved cases.     

Identification and characterization of novel uroporphyrinogen decarboxylase gene mutations in a large series of porphyria cutanea tarda patients and relatives

Porphyria cutanea tarda (PCT) arises from decreased hepatic activity of uroporphyrinogen decarboxylase (UROD). Both genetic and environmental factors interplay in the precipitation of clinically overt PCT, but these factors may vary between different geographic areas. Decreased activity of UROD in erythrocytes was used to identify patients with UROD mutations among a group of 130 Spanish PCT patients. Nineteen patients (14.6%) were found to harbor a mutation in the UROD gene. Eight mutations were novel: M1I, 5del10, A22V, D79N, F84I, Q116X, T141I and Y182C. Five others were previously described: F46L, V134Q, R142Q, P150L and E218G. The new missense mutations and P150L were expressed in Escherichia coli. D79N and P150L resulted in proteins that were localized to inclusion bodies. The other mutations produced recombinant proteins that were purified and showed reduced activity (range: 2.3–73.2% of wild type). These single amino acid changes were predicted to produce complex structural alterations and/or reduced stability of the enzyme. Screening of relatives of the probands showed that 37.5% of mutation carriers demonstrated increased urinary porphyrins. This study emphasizes the role of UROD mutations as a strong risk factor for PCT even in areas where environmental factors (hepatitis C virus) have been shown to be highly associated with the disease.     

Medical students' experience of vaginal examinations of anaesthetised women

Medical students usually initially learn vaginal examination (VE) by examining consenting anaesthetised women. To assess their experience of this practice, a questionnaire was distributed to all 66 fifth-year students at the Wellington School of Medicine in 2005—53 students responded. Although 184 women were available to approach for consent, only 141 were approached—students claimed insufficient time as their major difficulty. All male students discussed consent with women only in the 2 hours preoperatively, whereas nine (28%) of the female students sought consent earlier on the day or the day before. Of the 114 women asked, 97 gave written consent, but the VE was conducted in only 76 women mostly because the supervising gynaecologist claimed time constraints or was uninterested. Four other women were examined when consent was uncertain and two without consent. All but one of the students considered the experience educationally valuable. Eleven responding students did not perform a VE, and if the 13 nonresponders also did not, more than one-third of students lack this educational opportunity prior to their final year. In conclusion, some students require more commitment to seeking consent, and some gynaecologists may need to better facilitate this learning opportunity so that the consent agreed with the woman and student is more often respected.