Intra-operative monitoring as an adjuvant to standard vagus nerve stimulation implantation.

PURPOSE: The treatment of refractory epilepsy by vagus nerve stimulation (VNS) is a well-established therapy. Complications following VNS insertion may be procedure-related or stimulation-related. Herein, we describe our technique of intra-operative neuro-monitoring (IONM) in an attempt to diminish these adverse events. METHODS: This retrospective study describes 66 consecutive patients between the ages of 3 and 12 years who had undergone primary VNS implantation. The study population consisted of two cohorts, one in which the VNS device was implanted according to the standard described technique and a second group in which IONM was used as an adjuvant during the VNS device placement. Prior to VNS insertion, a Pediatric Voice Handicap Index (PVHI) was performed to assess voice-related quality of life, and this was repeated at 3 months following VNS insertion. RESULTS: Sixty-six patients underwent the VNS implantation. Forty-three patients had a "standard" VNS insertion technique performed, whereas 23 had IONM performed during the VNS implantation. There were significant changes in the PVHI scores across both cohorts at 3-month follow-up. There were no statistically significant differences in PVHI scores between the monitored group and non-monitored group at 3-month follow up. CONCLUSIONS: IONM can be used during VNS insertions to ensure correct placement of the leads on CNX. IONM may minimise vocal cord stimulation by placing the lead coils on the area of nerve eliciting the least amount of vocal cord EMG response. IONM however does not appear to improve voice outcomes at early follow up.

Use of intra-operative stimulation of brainstem lesion target sites for frameless stereotactic biopsies.

INTRODUCTION: Frameless stereotactic navigation is used to direct the trajectory and biopsy site of target lesions. We report on a novel intra-operative stimulating (IOS) probe that is integrated into a commercially available stereotactic biopsy needle with the rationale that stimulation of the intended biopsy site should predict functional tissue thus preventing inadvertent biopsy of eloquent tissue. METHODS: Patients undergoing brainstem biopsies for atypical lesions were offered the additional stimulation procedure. The IOS probe was used to deliver stimulation in an attempt to determine the proximity of eloquent tissue. Once the desired location of the biopsy needle was achieved, the IOS probe was inserted down the centre of the biopsy needle and the stimulus applied. If no action potential was recorded, biopsies from four quadrants of the lesion were taken. If however a compound action potential was recorded, a new target was selected. RESULTS: Nine patients had the biopsy and stimulation procedure performed. The median age was 36 months. A minimum of 8 samples were obtained from each patient. Biopsy material was adequate to obtain a diagnosis in all 9 patients. In 2 cases use of the device influenced the insertion trajectory or biopsy site. No patients experienced any complications directly attributable to either the biopsy procedure or application of the stimulation. CONCLUSIONS: Use of the IOS probe for intra-operative stimulation of the intended brainstem biopsy site was found to be safe and feasible. The addition of stimulation using the IOS probe can be done with minimal change in workflow.

First fossil Eriocottidae discovered in Eocene Baltic amber (Insecta: Lepidoptera).

Eocompsoctena macroptera gen. et sp. nov., the first fossil eriocottid moth, is described from Baltic amber and attributed to the Compsocteninae. Comparisons are provided with the related families Dryadaulidae, Meessiidae, Psychidae, and Tineidae. The new species confirms the antiquity of 'Tineoidea' grade diversification. The putative Gondwanan origin of Eriocottidae is discussed.

Coleophora meridiogallica Baldizzone, Huemer Nel, sp. n. from France (Lepidoptera, Coleophoridae).

Coleophora meridiogallica sp. n., a new species detected as a result of a DNA study, is described and compared with C. meridionella Rebel, 1912 with which it was confused. The new species whose larvae feed on Silene saxifraga is known only from a few departments of southeastern France.

Experimental evidence for heat plume-induced cavitation and xylem deformation as a mechanism of rapid post-fire tree mortality.

Recent work suggests that hydraulic mechanisms, rather than cambium necrosis, may account for rapid post-fire tree mortality. We experimentally tested for xylem cavitation, as a result of exposure to high-vapour-deficit (D) heat plumes, and permanent xylem deformation, as a result of thermal softening of lignin, in two tree species differing in fire tolerance. We measured percentage loss of conductance (PLC) in distal branches that had been exposed to high-D heat plumes or immersed in hot water baths (high temperature, but not D). Results were compared with predictions from a parameterized hydraulic model. Physical damage to the xylem was examined microscopically. Both species suffered c. 80% PLC when exposed to a 100°C plume. However, at 70°C, the fire-sensitive Kiggelaria africana suffered lower PLC (49%) than the fire-resistant Eucalytpus cladocalyx (80%). Model simulations suggested that differences in PLC between species were a result of greater hydraulic segmentation in E. cladocalyx. Kiggelaria africana suffered considerable PLC (59%), as a result of heat-induced xylem deformation, in the water bath treatments, but E. cladocalyx did not. We suggest that a suite of 'pyrohydraulic' traits, including hydraulic segmentation and heat sensitivity of the xylem, may help to explain why some tree species experience rapid post-fire mortality after low-intensity fires and others do not.

Coleophoranepetellae Baldizzone & Nel, a new species of the C.lixella group (Lepidoptera, Coleophoridae) from France and Italy.

Coleophoranepetellae Baldizzone & Nel, sp. n. is described from the southern Alps (Italy and France). It belongs to the Coleophoralixella species group. Its host plants are Nepetanepetella L. (Lamiaceae) and an unidentified Poaceae. The fifth instar larva, its case, the adult habitus, and genitalia are illustrated. The species is compared to Coleophoranevadella Baldizzone, 1985, here newly confirmed from France and whose larvae feed on Nepetalatifolia DC. in the Eastern Pyrénées. DNA barcodes are shown to be distinct and congruent with morphological differences among species of the lixella group. Barcodes revealed that Coleophoratricolor Walsingham, 1889, formerly known only from Great Britain, is also present in France and Greece.

RésuméColeophoranepetellae Baldizzone & Nel, sp. n. du groupe de Coleophoralixella Zeller, 1849., est décrite des Alpes méridionales (Italie et France). La plante-hôte de ponte est la Lamiacée Nepetanepetella L. et celle de la larve à maturité est une espèce non-identifiée de Poaceae. La chenille L5 et son fourreau, l'habitus et les genitalia mâles et femelles sont figurés. L'espèce est comparée à Coleophoranevadella Baldizzone, 1985, espèce ici confirmée pour la France où elle est inféodée à Nepetalatifolia DC. dans les Pyrénées-Orientales. Enfin, la validité de cette nouvelle espèce est confirmée par l'étude des codes-barres ADN du groupe lixella. Les codes-barres ont aussi révélé la présence de Coleophoratricolor Walsingham, 1889 en France et en Grèce alors que l'espèce n'était auparavant connue que de la Grande-Bretagne.