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• National DRLs for interventional procedures have been proposed given level of complexity • For clinical audits, the level of complexity should be taken into account. • An evaluation of the complexity levels of the procedure should be made.

In general, effective dose values for similar interventional vascular radiology (IVR) procedures are different. This is due to problems with the classification of radiological procedures, which make comparisons difficult. Patient size, examination technique and clinical condition as well as the skill of the medical radiologists also affect effective dose. Currently, there is a broad agreement on the classification of similar procedures so that effective dose estimates can be made from measurements of the dose area product (DAP). Thus, reference dose values may be established and comparative studies between different services and hospitals can be made. The objective of this study is to provide dose data for some digital angiographic and interventional procedures. Values of measured DAP for 143 patients for five types of procedures are presented. Procedures investigated were abdominal angiography, arteriography of lower limbs, biliary drainage, embolization of spermatic vein and nephrostomy. All the procedures were performed using digital equipment. Values of DAP and effective dose were 30 Gy cm2 and 6.2 mSv for arteriography of lower limbs and 150 Gy cm2 and 38.2 mSv for biliary drainage. In each one of these procedures, effective dose values per minute of fluoroscopy and per radiography film have been calculated. It is possible to use this information for the rapid estimation of effective dose.

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The dose-area product was higher with the digital system than with the conventional system in 13 of the 15 groups. To reduce the patient dose in vascular interventional radiology procedures, the training of personnel and the frequent use of conventional fluoroscopy and low-dose imaging are required.

The objective of this work was to estimate patient doses (dose-area product, organ dose, effective dose and entrance surface dose) for barium procedures. A total of 175 procedures, in 175 patients, for five different examination categories was analysed. Dose-area product was determined using a transmission ionization chamber. Organ dose and effective dose were assessed using a knowledge of the examination and the software. For all patients, the contribution of fluoroscopy to the total dose was greater than that from radiography. Dose-area product from double contrast barium enema, enteroclysis and intestinal tract procedures was higher than that obtained for the other procedures. The average effective dose was 1.04 mSv and 13.99 mSv for oesophageal tract and enteroclysis examinations, respectively. Entrance surface dose in the oesophageal tract was 16 mGy, 10 times lower than for the other four procedures. Patient dose reduction in barium procedures may be achieved by improved training of resident radiologists, senior radiologists and other specialists in radiation protection.

We report the rare case of a patient, JNR, with history of mixed handedness, developmental dyslexia, dysgraphia, and attentional deficits associated with a Klippel-Trenaunay syndrome and a small subcortical frontal lesion involving the left arcuate fasciculus. In adulthood, he suffered a large right perisylvian stroke and developed atypical conduction aphasia with deficits in input and output phonological processing and poor auditory-verbal short-term memory. Lexical-semantic processing for single words was intact, but he was unable to access meaning in sentence comprehension and repetition. Reading and writing deficits worsened after the stroke and he presented a combination of developmental and acquired dysgraphia and dyslexia with mixed lexical and phonological processing deficits. This case suggest that a small lesion sustained prenatally or early in life could induce a selective rightward shift of phonology sparing the standard left hemisphere lateralisation of lexical-semantic functions.

Lesion-symptom mapping studies reveal that selective damage to one or more components of the speech production network can be associated with foreign accent syndrome, changes in regional accent (e.g., from Parisian accent to Alsatian accent), stronger regional accent, or re-emergence of a previously learned and dormant regional accent. Here, we report loss of regional accent after rapidly regressive Broca’s aphasia in three Argentinean patients who had suffered unilateral or bilateral focal lesions in components of the speech production network. All patients were monolingual speakers with three different native Spanish accents (Cordobés or central, Guaranítico or northeast, and Bonaerense). Samples of speech production from the patient with native Córdoba accent were compared with previous recordings of his voice, whereas data from the patient with native Guaranítico accent were compared with speech samples from one healthy control matched for age, gender, and native accent. Speech samples from the patient with native Buenos Aires’s accent were compared with data obtained from four healthy control subjects with the same accent. Analysis of speech production revealed discrete slowing in speech rate, inappropriate long pauses, and monotonous intonation. Phonemic production remained similar to those of healthy Spanish speakers, but phonetic variants peculiar to each accent (e.g., intervocalic aspiration of /s/ in Córdoba accent) were absent. While basic normal prosodic features of Spanish prosody were preserved, features intrinsic to melody of certain geographical areas (e.g., rising end F0 excursion in declarative sentences intoned with Córdoba accent) were absent. All patients were also unable to produce sentences with different emotional prosody. Brain imaging disclosed focal left hemisphere lesions involving the middle part of the motor cortex, the post-central cortex, the posterior inferior and/or middle frontal cortices, insula, anterior putamen and supplementary motor area. Our findings suggest that lesions affecting the middle part of the left motor cortex and other components of the speech production network disrupt neural processes involved in the production of regional accent features.