Feasibility of stereotactic MRI-based image guidance for the treatment of vascular malformations: a phantom study.

PURPOSE Treatment of vascular malformations requires the placement of a needle within vessels which may be as small as 1 mm, with the current state of the art relying exclusively on two-dimensional fluoroscopy images for guidance. We hypothesize that the combination of stereotactic image guidance with existing targeting methods will result in faster and more reproducible needle placements, as well as reduced radiationexposure, when compared to standard methods based on fluoroscopy alone. METHODS The proposed navigation approach was evaluated in a phantom experiment designed to allow direct comparison with the conventional method. An anatomical phantom of the left forearm was constructed, including an independent control mechanism to indicate the attainment of the target position. Three interventionalists (one inexperienced, two of them frequently practice the conventional fluoroscopic technique) performed 45 targeting attempts utilizing the combined and 45 targeting attempts utilizing the standard approaches. RESULTS In all 45 attempts, the users were able to reach the target when utilizing the combined approach. In two cases, targeting was stopped after 15 min without reaching the target when utilizing only the C-arm. The inexperienced user was faster when utilizing the combined approach and applied significantly less radiation than when utilizing the conventional approach. Conversely, both experienced users were faster when using the conventional approach, in one case significantly so, with no significant difference in radiation dose when compared to the combined approach. CONCLUSIONS This work presents an initial evaluation of a combined navigation fluoroscopy targeting technique in a phantom study. The results suggest that, especially for inexperienced interventionalists, navigation may help to reduce the time and the radiation dose. Future work will focus on the improvement and clinical evaluation of the proposed method.

Benzodiazepine use in pregnancy and major malformations or oral cleft: meta-analysis of cohort and case-control studies

Objective: To determine if exposure to benzodiazepines during the first trimester of pregnancy increases risk of major malformations or cleft lip or palate.

Retinoid X receptor-selective ligands produce malformations in Xenopus embryos.

Retinoids exert pleiotropic effects on the development of vertebrates through the action of retinoic acid receptors (RAR) and retinoid X receptors (RXR). We have investigated the effect of synthetic retinoids selective for RXR and RAR on the development of Xenopus and zebrafish embryos. In Xenopus, both ligands selective for RAR and RXR caused striking malformations along the anterior-posterior axis, whereas in zebrafish only ligands specific for RAR caused embryonic malformations. In Xenopus, RAR- and RXR-selective ligands regulated the expression of the Xlim-1, gsc, and HoxA1 genes similarly as all-trans-retinoic acid. Nevertheless, RXR-selective ligands activated only an RXR responsive reporter but not an RAR responsive reporter introduced by microinjection into the Xenopus embryo, consistent with our failure to detect conversion of an RXR-selective ligand to different derivatives in the embryo. These results suggest that Xenopus embryos possess a unique response pathway in which liganded RXR can control gene expression. Our observations further illustrate the divergence in retinoid responsiveness between different vertebrate species.

Surgical diseases of the kidney and ureter including injuries, malformations and misplacements,

Mode of access: Internet.

The surgery of oral diseases and malformations, their diagnosis and treatment,

Mode of access: Internet.

A practical treatise on the ætiology, pathology, and treatment of the congenital malformations of the rectum and anus.

Spine title: Congenital malformations of the rectum & anus.

Maternal valproate dosage and foetal malformations

Objective - To study the possible dose dependence of the foetal malformation rate after exposure to sodium valproate in pregnancy Methods - Analysis of records of all foetuses in the Australian Registry of Antiepileptic Drugs in Pregnancy exposed to valproate, to carbamazepine, lamotrigine or phenytoin in the absence of valproate, and to no antiepileptic drugs. Results - The foetal malformation rate was higher (P < 0.05) in the 110 foetuses exposed to valproate alone (17.1%), and in the 165 exposed to valproate, whether alone or together with the other antiepileptic drugs (15.2%), than in the 297 exposed to the other drugs without valproate (2.4%). It was also higher (P < 0.10) than in the 40 not exposed to antiepileptic drugs (2.5%). Unlike the situation for the other drugs, the malformation rate in those exposed to valproate increased with increasing maternal drug dosage (P < 0.05). The rate was not altered by simultaneous exposure to the other drugs. Valproate doses exceeding 1400 mg per day seemed to be associated with a more steeply increasing malformation rate than at lower doses and with a different pattern of foetal malformations. Conclusion - Foetal exposure to valproate during pregnancy is associated with particularly high, and dose-dependent risks of malformation compared with other antiepileptic drugs, and may possibly involve different teratogenetic mechanisms.

Foetal malformations and seizure control: 52 months data of the Australian Pregnancy Registry

The Australian Pregnancy Registry, affiliated European Register of Antiepileptic drugs in Pregnancy (EURAP), recruits informed consenting women with epilepsy on treatment with antiepileptic drugs (AEDs), those untreated, and women on AEDs for other indications. Enrolment is considered prospective if it has occurred before presence or absence of major foetal malformations (FMs) are known, or retrospective, if they had occurred after the birth of infant or detection of major FM. Telephone Interviews are conducted to ascertain pregnancy outcome and collect data about seizures. To date 630 women have been enrolled, with 565 known pregnancy outcomes. Valproate (VPA) above 1100 mg/day was associated with a significantly higher incidence of FMs than other AEDs (P < 0.05). This was independent of other AED use or potentially confounding factors on multivariate analysis (OR = 7.3, P < 0.0001). Lamotrigine (LTG) monotherapy (n = 65), has so far been free of malformations. Although seizure control was not a primary outcome, we noted that more patients on LTG than on VPA required dose adjustments to control seizures. Data indicate an increased risk of FM in women taking VPA in doses > 1100 mg/day compared with other AEDs. The choice of AED for pregnant women with epilepsy requires assessment of balance of risks between teratogenicity and seizure control.

Remaniements subtélomériques chez les foetus avec malformations majeures

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Participation de l'endocarde dans les malformations cardiaques du syndrome Holt-Oram

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Remaniements subtélomériques chez les foetus avec malformations majeures

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Participation de l'endocarde dans les malformations cardiaques du syndrome Holt-Oram

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Extracranial association of arteriovenous and venous malformations. Case report

Association of multiple vascular malformations of the face is a rare condition. An arteriovenous malformation (AVM) with a venous malformation as the draining vein is also a rarity. We report a case of extracranial mixed vascular malformations that deformed the normal architecture of the lower face. Removal of the AVM was followed by stability of the jaw and tongue malformation, indicating the AVM used the venous malformation as its draining vein. This approach spared the patient severe cosmetic and functional sequelae.