Bloqueo ecoguiado del nervio obturador al nivel de la rama púbica superior: estudio en cadáver embalsamado en Thiel utilizando látex / Sonographic obturator nerve block at level of superior pubic ramus: A Thiel based cadaveric investigation with latex

Introducción: El bloqueo del nervio obturador proximal tiene una eficacia similar al bloqueo del nervio obturador distal. Los estudios en cadáveres previos que inyectaban azul de metileno y realizaban seguidamente la disección reflejaron que la solución se dispersa a las divisiones anterior y posterior del nervio obturador, en el punto de salida del canal obturador. La absorción de azul de metileno por parte de la fascia y los músculos oscurece la delineación exacta de los nervios teñidos. Nosotros conjeturamos que la inyección de látex al nivel de las ramas púbicas superiores en el plano entre los músculos pectíneo y obturador externo mediante guía ecográfica a tiempo real, seguida de disección demorada en un cadáver embalsamado en Thiel, sería la técnica óptima de investigación en cadáveres. Métodos: Obtuvimos 3 cuerpos donados a la ciencia (BDTS) conforme a las normas estrictas del programa de donación del Departamento de Anatomía Macroscópica y Clínica de la Universidad de Medicina de Graz, y a la normativa sobre enterramientos de Estiria. Los BDTS fueron embalsamados utilizando el método de Thiel, que aporta condiciones muy realistas para las investigaciones con anestesia regional. En 2 cadáveres, las inyecciones de látex se realizaron de forma ecoguiada, y en el tercero se realizaron secciones transversales. Resultados: Nuestras disecciones abiertas de los cadáveres embalsamados en Thiel (C1 y C2) reflejaron que la inyección única de látex en el plano interfascial entre los músculos pectíneo y obturador externo al nivel de la rama púbica superior originó una dispersión adecuada a lo largo del tronco del nervio obturador y sus ramas, en todas las muestras. Conclusiones: La inyección ecoguiada de látex dentro del plano al nivel de las ramas púbicas superiores entre los músculos pectíneo y obturador externo cubre las ramas anterior y posterior y el tronco del nervio obturador.(AU)

Introduction: A proximal obturator nerve block has a similar block efficacy as the distal obturator nerve block. Previous cadaveric investigation injecting methylene blue dye solution and an immediate dissection proved the solution engulfing the anterior and posterior divisions of the obturator nerve as they emerge from the obturator canal. Uptake of methylene blue dye by the fascia and muscles obscures the exact delineation of the stained nerves. We hypothesized that injection of latex at the level of superior pubic rami in the plane between pectineus and obturator externus under real time ultrasound and a delayed dissection in a Thiel-based cadaver would be the optimal cadaveric investigational technique. Methods: Three investigated bodies donated to science (BDTS) fall under the strict rules of the donation program of the Department of Macroscopic and Clinical Anatomy of the Medical University of Graz and the Styrian burial law. The BDTS were embalmed with Thieĺs method which provides very lifelike conditions for investigations with regional anaesthesia backgrounds. In two cadavers (a total of specimens), latex injections were performed under ultrasound, while in the third cadaver cross-sections were executed. Results: Our Thiel based cadaveric open dissection (C1 and C2) demonstrated that a single injection of latex in the inter-fascial plane between the pectineus muscle and the obturator externus muscle at the level of superior pubic ramus led to adequate spread along trunk of the obturator nerve and its branches in all specimens. Conclusions: An in-plane ultrasound-guided latex injections at the level of superior pubic rami, between the pectineus and the obturator externus muscles soaks the anterior ramus, posterior ramus, and the obturator nerve trunk.(AU)

Dorsal minimally invasive plate osteosynthesis of the distal tibia with regard to adjacent anatomical characteristics.

INTRODUCTION: The aim of this study was to perform MIPO of the distal tibia from a dorsomedial and dorsolateral approach and to evaluate their feasibility and risk of injury to adjacent anatomical structures. MATERIAL & METHODS: A total of 18 extremities from 9 adult human cadavers was included in the study. In each cadaver, one lower leg underwent application of a 12-hole 3.5 LCP metaphyseal plate from the medial and the further one from the lateral approach. For the medial approach, a 4 cm skin incision was performed at the tibial border of the Achilles tendon, starting from 1 cm proximal to its insertion point at the calcaneal tuberosity. Entrance was gained between the medial border of the flexor hallucis longus tendon and the medial neurovascular bundle. Regarding the lateral approach, the skin was incised over a length of about 4 cm at the lateral border of the Achilles tendon, approximately 1 cm proximal to its insertion point. Entrance was gained between the Achilles tendon and the peroneus brevis muscle. The plates were inserted in direct bone contact in a proximal direction and the proximal and distal ends were fixed. During dissection, the proximal and distal holes beneath the crossing points of the neurovascular bundle and the plate were noted. The distal and proximal intersection points of the neurovascular bundle and the plate were measured with reference to the distal border of the plate. RESULTS: Concerning the medial approach, the neurovascular bundle was on median located between the 6th and 11th plate holes starting from distal. The bundle intersected the plate distally at a mean height of 65.8 mm and proximally at 156.8 mm on average. For the lateral approach, the neurovascular bundle was situated between the 6th and the 12th plate hole from distal. It crossed the plate distally at a mean of 61.0 mm and proximal at a mean height of 153.9 mm. In none of the cases, lacerations of the neurovascular bundle were observed. CONCLUSION: In conclusion, MIPO from the dorsomedial and dorsolateral approach are both safe procedures as indicated by our study.

[Outpatient treatment of acute injuries of upper extremities with axillary plexus anesthesia in the emergency department-Is that possible without continuous anesthesia attendance?] / Ambulante Versorgung akuter Verletzungen der oberen Extremität in der Notfallambulanz in axillärer Plexusanästhesie ­ Ist das ohne durchgehende Anästhesiebegleitung machbar?

BACKGROUND: The incorporation into the routine operating procedure of patients with small but acute hand and forearm injuries requiring surgery who present in the emergency admission department, represents a challenge due to limited resources. The prompt treatment in the emergency admission department represents an alternative. This article retrospectively reports the authors' experiences with a treatment algorithm in which emergency patients were treated by ultrasound-guided axillary brachial plexus blocks (ABPB) and surgery carried out in the emergency department without further anesthesia attendance. METHODS: Patients were preselected by the surgeon if they were suitable for a standardized treatment without anesthesia attendance during surgery. If there were no anesthesiological or surgical contraindications patients received an ABPB in the holding area of the operating room (OR) under standard monitoring. Blocks were performed as a multi-injection, ultrasound-guided technique which is anatomically described in detail. Patients >60 kg received a total volume of 30 ml of a mixture of 10 ml 1% ropivacaine (100 mg) and 20 ml 2% prilocaine (400 mg). Patients <60 kg received the same mixture with a reduced volume of 25 ml corresponding to 82.5 mg ropivacaine and 332.5 mg prilocaine. After controlling for block success patients were admitted to the emergency department and the surgical procedure was carried out under supervision by the surgeon without further anesthesia attendance. At discharge patients were explicitly instructed that in the case of any complications or a continuation of the block for more than 24 h they should contact the emergency department. RESULTS: Between January 2013 and November 2017 a total of 566 patients (46.4 years, range 11-88 years, 174.9 cm, range 140-211cm, 80.8 kg, range 42-178kg, ASA 1/2/3, 190/338/38, respectively) were treated according to a standardized protocol. The ABPBs were performed by 74 anesthetists. In 5% of the patients the initial block was incomplete and rescue blocks were performed with a maximum of 2­3ml 1% prilocaine per corresponding nerve. After completion the block was ensured and all patients underwent surgery without further analgesics or local anesthetic infiltration by the surgeon. Complications related to the ABPB and readmissions were not observed. CONCLUSION: It could be demonstrated that minor surgery could be carried out safely and effectively with a defined algorithm using ABPB in selected patients outside the OR without permanent anesthesia attendance: however, indispensable prerequisites for such procedures are careful patient selection, patient compliance, the safe and effective performance of the ABPB and reliable agreement with the surgeon.

S-Nitrosothiol Signaling Is involved in Regulating Hydrogen Peroxide Metabolism of Zinc-Stressed Arabidopsis.

Accumulation of heavy metals such as zinc (Zn) disturbs the metabolism of reactive oxygen (e.g. hydrogen peroxide, H2O2) and nitrogen species (e.g. nitric oxide, NO; S-nitrosoglutathione, GSNO) in plant cells; however, their signal interactions are not well understood. Therefore, this study examines the interplay between H2O2 metabolism and GSNO signaling in Arabidopsis. Comparing the Zn tolerance of the wild type (WT), GSNO reductase (GSNOR) overexpressor 35S::FLAG-GSNOR1 and GSNOR-deficient gsnor1-3, we observed relative Zn tolerance of gsnor1-3, which was not accompanied by altered Zn accumulation capacity. Moreover, in gsnor1-3 plants Zn did not induce NO/S-nitrosothiol (SNO) signaling, possibly due to the enhanced activity of NADPH-dependent thioredoxin reductase. In WT and 35S::FLAG-GSNOR1, GSNOR was inactivated by Zn, and Zn-induced H2O2 is directly involved in the GSNOR activity loss. In WT seedlings, Zn resulted in a slight intensification of protein nitration detected by Western blot and protein S-nitrosation observed by resin-assisted capture of SNO proteins (RSNO-RAC). LC-MS/MS analyses indicate that Zn induces the S-nitrosation of ascorbate peroxidase 1. Our data collectively show that Zn-induced H2O2 may influence its own level, which involves GSNOR inactivation-triggered SNO signaling. These data provide new evidence for the interplay between H2O2 and SNO signaling in Arabidopsis plants affected by metal stress.

Minimal invasive plating of distal radius fractures. A safe procedure?

BACKGROUND: Minimal invasive plate osteosynthesis (MIPO) with preservation of the pronator quadratus (PQ) muscle represents a new technique for stabilization of distal radius fractures. However, the complex anatomy of the distal radius metaphysis requires implants with features that address all morphologic specifics of this area to avoid complications, which are still reported with this technique. It was the aim of our anatomic investigation to evaluate the feasibility of plate insertion via a minimal transverse approach as well as the risk of soft- tissues compromise with the use of an implant, which is only partially adapted to the characteristics of distal radius metaphysis. METHODS: Twenty forearm specimens, conservated with Thiels method, have been used for this study. The majority (n = 19/20) of implants (2.4 mm small fragment juxta-articular locking compression/ LCP T-plate -5-hole; Depuy - Synthes®, Solothurn, Switzerland) could be inserted easily and all were seated proximal to the so called "watershed line" (n = 20/20). RESULTS: In a total of 8/20 specimens close contacts or potential compromise to neighboring soft- tissues was seen: perforation of the PQ muscle by the plate occurred in 2/20 specimens and was related to an extreme muscle morphology. In 7/20 specimens close contacts between the T-plate and other soft tissues were observed, which were exclusively located at the radial edge of the distal transverse bar. They affected the brachio-radialis tendon (elevation: 2/20, side-to-side contact: 3/20, overriding: 1/20) and the radial artery (elevation: 4/20, side-to-side contact: 2/20, overriding: 1/20). No significant differences of morphologic types of PQ muscle and the difficulty of plate insertion, adjustment on the bone, PQ muscle damage and contact to neighboring soft-tissues could be evaluated. CONCLUSIONS: Insertion of volar radius plates through a MIPO approach can be easily accomplished without detachment and damage to the PQ muscle even with grossly adapted implants. However, perfectly pre-shaped plates which are adapted to all anatomic aspects of the distal radius metaphysis are required to achieve optimal contact with the metaphyseal bone and to avoid potential complications.

Plant selenium toxicity: Proteome in the crosshairs.

The metalloid element, selenium (Se) is in many ways special and perhaps because of this its research in human and plant systems is of great interest. Despite its non-essentiality, higher plants take it up and metabolize it via sulfur pathways, but higher amounts of Se cause toxic symptoms in plants. However, the molecular mechanisms of selenium phytotoxicity have been only partly revealed; the data obtained so far point out that Se toxicity targets the plant proteome. Besides seleno- and oxyproteins, nitroproteins are also formed due to Se stress. In order to minimize proteomic damages induced by Se, certain plants are able to redirect selenocysteine away from protein synthesis thus preventing Se-protein formation. Additionally, the damaged or malformed selenoproteins, oxyproteins and nitroproteins may be removed by proteasomes. Based on the literature this review sets Se toxicity mechanisms into a new concept and it draws attention to the importance of Se-induced protein-level changes.

Ultrasound-guided anterior approach to the axillary and intercostobrachial nerves in the axillary fossa: an anatomical investigation.

BACKGROUND: The posterolateral and medial aspect of the arm is supplied by the axillary (AXN) and intercostobrachial nerves (ICBN), which are not anaesthetised by an axillary brachial plexus block (ABPB). Blockade of the AXN and the ICBN has been reported in the quadrangular space (QS) posteriorly or by serratus plane block, respectively. An anterior ultrasound-guided approach to block the AXN and ICBN would be desirable to complete an ABPB at a single insertion site. METHODS: After a preliminary dissection study in six cadavers, ultrasound-guided AXN and ICBN injection was performed in 46 Thiel embalmed cadavers bilaterally. Key sonographic landmarks to identify the AXN in the QS are the humerus, teres major muscle, and subscapular muscle. With the same probe position, the ICBN was identified in the subfascial axillary space. Then, 2 ml latex was injected at each nerve and confirmed by dissection. RESULTS: Muscular and bony landmarks were identified in all cadavers. The AXN was seen in 99% in the QS or at the inferolateral margin of the subscapular muscle and surrounded by latex in 96% of cases. Latex spread to the axillary fossa, within the subscapular muscle, or to the radial nerve was noted in 8% of the injections. The ICBN was seen and surrounded by latex in 100% of cases. CONCLUSIONS: We describe a reliable ultrasonographic approach to visualise the AXN and ICBN anteriorly from the conventional ABPB approach as confirmed in this cadaver study.

[Lumbar CT-guided radiofrequency ablation of the medial branch of the dorsal ramus of the spinal nerve : Anatomic study and description of a new technique]. / Lumbale CT-gezielte Radiofrequenzablationen des Ramus medialis rami dorsalis nervi spinalis : Anatomische Untersuchung und Beschreibung einer neuen Technik.

BACKGROUND: The success of radiofrequency ablation (RF) of the medial branch of the dorsal ramus in patients with facet joint pain depends on the effective coagulation distance. To date, computed tomography(CT)-guided techniques do not reach the nerve in parallel but rather than punctually. We report a new CT-guided technique to enhance parallelism and proximity of the RF needle to the nerve. MATERIALS AND METHODS: Two examiners with different experience with CT-guided procedures in corpses performed all punctures at the lumbar spine on 10 corpses. A RF needle was inserted 1 cm lateral to the spinous process of the vertebra located caudal to the target nerve. The needle was advanced under CT guidance at a flat angle between the superior articular process and the base of the costal or transverse process of the cranial vertebra. The position was verified by dissection. Needle position was judged successful provided the needle could be positioned in the first attempt with no more than one angle correction. RESULTS: In 86 out of 100 possible cases (50 per side) at the 5 lumbar segments, the RF needle could be depicted by CT in the target area with no more than one correction of the needle position. Anatomical dissections revealed that 47 out of 86 needles (54.6%) fulfilled the requirements of parallelism and proximity to the nerve. The dorsal ramus was never reached by the RF needle. Higher success rates were obtained in the middle segments compared to the border segments of L1-L2 and L5-S1. CONCLUSIONS: We could demonstrate that the principle of parallelism and proximity of the needle to the nerve could be fulfilled with this new technique; however, needle positioning requires practice due to the oblique puncture direction.

Anatomy of the medial antebrachial cutaneous nerve and its significance in ulnar nerve surgery: An anatomical study.

BACKGROUND: During cubital tunnel surgery, the medial antebrachial cutaneous nerve (MACN) may be injured, causing painful scars, neuromas, hypaesthesia or hyperalgesia. As the literature on the anatomy of crossing branches in this area is contradictory, this study aimed to re-examine the anatomy of the MACN in this region. METHODS: Forty upper limbs were dissected. We looked specifically from 5 cm proximal to 6 cm distal to the medial epicondyle (ME) and documented the number of crossing branches and the distances between the crossing points and the ME; we also measured the length of each limb. RESULTS: The most common location for crossing branches was 2 cm distal to the ME. Twenty-seven branches (∼23%) were found proximal to or at the level of the ME, and 91 branches (∼77%) were distal to it. The average distance between the proximal crossing points and the ME was 1.7 cm, the mean number of crossing branches was 0.7 and at least one crossing branch per limb was found in 16/40 cases. For the distal crossing points, the average distance to the ME was 2.9 cm, the mean number of crossing branches was 2.3 and at least one crossing branch per limb was found in all cases. There was no correlation between the limb lengths and the number of crossing branches. CONCLUSION: Because the incidence of posterior branches of the MACN crossing the course of the ulnar nerve is 100%, it is important to take the anatomy of the MACN into consideration when undertaking ulnar nerve surgery.

Thermocoagulation of the Medial Branch of the Dorsal Branch of the Lumbal Spinal Nerve: Flouroscopy Versus CT.

Objective: For radiofrequency neurotomy of the medial branch of the lumbar dorsal rami, physicians use techniques guided either by fluoroscopy or computerized tomography (CT), and advocate for their respective techniques. Crucial to the choice of technique is how well each can capture the target nerve. The present study was, therefore, undertaken to assess in cadavers the accuracy of fluoroscopic-guided and CT-guided techniques. Design: In10 cadavers preserved with Thiel's method, electrodes with 10mm active tips were placed in supine position on the right using a fluoroscopic-guided technique, and on the left using a CT-guided technique. Using a special dissection approach, the relationship between the target nerve and the tip of the electrode was revealed. The displacement between electrode and the nerve, and the extent to which the electrode was parallel to the nerve, were measured with callipers. Results: Under fluoroscopy guidance, electrodes were placed accurately beside the nerve, and were parallel to it for 9 ±1.9 mm. In only two cases did the electrode pass too deeply. Under CT guidance, electrodes often failed to reach the nerve, but when they did they were parallel to it for only 3.2 ± 3.2 mm. In seven cases, the electrode passed too deeply beyond the target nerve. Conclusion: The fluoroscopy-guided technique can be relied upon to achieve optimal placement of electrodes on the lumbar medial branches. The CT-guided technique fails to do so, and should not be used in practice until a modified version has been developed and validated.

Susceptibility of the genitofemoral and lateral femoral cutaneous nerves to complications from lumbar sympathetic blocks: is there a morphological reason?

BACKGROUND: Interference with the function of the genitofemoral nerve (GFN) and lateral femoral cutaneous nerve (LFCN) represents a significant complication of lumbar sympathetic blocks (LSBs). The nerve topography of the lumbar sympathetic trunk (LST) was investigated to find a possible morphological reason for this. METHODS: A total of 118 cadavers embalmed by Thiel's method were investigated. The nerves were dissected from their innervation area to their paravertebral origins. Distances of the GFN and the LFCN to the LST were measured at levels L2/3, L3/4, and L4/5, which are the most common levels for LSB. RESULTS: Two hundred and thirteen sides were assessable for the GFN and 151 sides for the LFCN. In 186 cases, the whole GFN (in 20 cases, its femoral branch only) approached the medial margin of the psoas major (PM) and passed the LST laterally at the level of L3/4 and a distance of 0-28 mm (mean distance 8.5 mm; sd 6.7 mm) and ran dorsally between the PM and the vertebral body of L3, reaching the intervertebral foramen L2/3. In three cases, the GFN fused with the LFCN. In 55 cases, the GFN-LST distance was 0-13 mm at L4/5 and in 19 cases, 9-19 mm at L2/3. The LFCN approached the lateral margin of the PM and entered the intervertebral foramen at L2/3 in 141 cases. CONCLUSIONS: There is a higher risk of LSB affecting the GFN at L3/4 or L4/5 during neurolysis of the LST due to its topography. The LFCN rarely shows a strong relation to the LST and only when fused with the GFN.

Anatomical investigation of a new vertical obturator nerve block technique.

BACKGROUND: We evaluated a vertical obturator nerve block (VOB) using a single morphological landmark and no additional distance measurement or obligatory changes of the needle's direction. MATERIALS AND METHOD: A total of 88 cadavers (176 lower limbs), prepared using Thiel's embalming method, were examined. The index finger was placed lateral to the palpable pubic tubercle and the needle inserted laterally to the distal part of the fingernail at the tubercle's level and advanced strictly perpendicular to the table's surface. If bone contact was made, the needle was slightly turned to pass the bone distally. Colored latex (5 ml) was then injected. The injection depth was documented, then followed by dissection and nerve exposition. The real skin-nerve distance and the degree of difficulty in orientation and of palpation were measured. Additionally, the dissemination around the nerve or its branches and the intrapelvic spread were documented. RESULTS: The nerve was colored completely in 93.75%, partially in 1.71%, and not colored in 4.54% of cases. The mean injection depth was 3.9 cm (±0.7 SD) and real nerve depth was 3.8 cm (±0.69 SD). Bone contact necessitating the needle's redirection was found in 20 (11.4%) cases. Easy orientation and palpation of the tubercle was always found. In 40 cases, the latex spread via the obturator canal into the lesser pelvis. CONCLUSION: In this anatomical study, the VOB technique exhibits easy orientation without stimulation or ultrasound guidance. The nerve was located at a constant depth. The injection offered a high percentage of colored nerves.

Hypericin for visualization of high grade gliomas: first clinical experience.

AIMS: We aimed to demonstrate that Hypericin, a component of St. Johns Wort, selectively visualizes malignant gliomas. Hypericin is known as one of the most powerful photosensitizers in nature with excellent fluorescent properties. METHODS: In five patients with a recurrence of a malignant glioma a newly developed water soluble formulation of hypericin was given intravenously (0.1 mg/kg body weight) 6 h before the surgical procedure. Tumor resection was performed under white light and fluorescence mode. The intensity grade of the tissue fluorescence was categorisized by the surgeon in three grades, highly fluorescent, weakly fluorescent and not fluorescent. In these areas tissue samples were taken and investigated by two blinded independent neuropathologists. Tissue samples were histologically classified differentiating between tumor tissue, tumor necrosis, tissue with scattered tumor cells and normal brain tissue. RESULTS: In all patients tumor tissue was clearly distinguishable by its typically red fluorescence color from normal brain tissue which was colored blue under a special fluorescent filter. Histological evaluation of the 110 tissue samples showed a specificity of 100% and sensitivity of 91% for one of the two neuropathologists, whereas specificity for second pathologist was 90% and sensitivity 94%. The i.v. application of Hypericin proofed to be safe in all cases and there were no side effects observed. CONCLUSION: Hypericin in its water soluble form is a well tolerated drug. In addition to its high photosensitizing properties hypericin will open up interesting new therapeutic possibilities especially when used in combination with fluorescence detection and simultaneously photodynamic therapy.

Levetiracetam compared to phenytoin for the prevention of postoperative seizures after craniotomy for intracranial tumours in patients without epilepsy.

Anticonvulsant drugs are frequently given after craniotomy. Phenytoin (PHT) is the most commonly used agent; levetiracetam (LEV) is a new anticonvulsant drug with fewer side effects. To compare the incidence of seizures in patients receiving either prophylactic PHT or LEV perioperatively, 971 patients undergoing a craniotomy were analysed retrospectively during a 2-year period. PHT was used routinely and LEV was administered when PHT was contraindicated. Seizures documented during the first 7 days after craniotomy were considered. A total of 235 patients were treated with an antiepileptic drug: 81 patients received LEV, and 154 patients, PHT. Two patients receiving LEV (2.5%) and seven receiving PHT (4.5%) had a seizure despite this treatment. No patient had a documented side effect or drug interaction. The data show that LEV may be an alternative option in patients with contraindications to PHT.

The superficial palmar arch and median artery as an example of misleading results due to a small number of investigated specimens or the use of different classifications.

BACKGROUND: Small numbers of investigated specimens might lead to misinterpretations. Different classifications can change results dramatically. This is demonstrated by an investigation of the superficial palmar arch and the palmar median artery. MATERIALS AND METHODS: A total of 702 upper limbs were investigated. Data were collected during eight dissection courses for advanced medical students and one workshop of hand surgery (number of investigated limbs per course between 52 and 111). The variations of superficial palmar arches were documented according to the classification of Lippert and Pabst as well as the occurrence of a palmar median artery. The results of each course were compared among each other, to the total result and compared to allocation according Jaschtschinski's classification. RESULTS: In total, the results show complete arches in 52.15%. Incomplete arches with the ulnar artery supplying the thumb in 15.38%, reaching the index in 22.15% and the middle finger in 10.32%. Median arteries were documented in 4.5%. Individual course results varied concerning complete arches from 41.1% (37 out of 90) and 65% (35 out of 55), median arteries were found between 0 (0 of 69 hands) and 9.1% (5 of 55 hands). Classifying our total result with Jaschtschinski's classification there would have been complete arches in 67.8% (individual course result: 43.3-81.8%). CONCLUSIONS: Small numbers of investigated specimens can lead to confounding results. The classification used has to be precisely determined. Both classifications need to be known to interpret results correctly. A repetition of investigation might be performed to confirm results.

Consecutive, prospective case series of a new method for ultrasound-guided supraclavicular approach to the brachiocephalic vein in children.

BACKGROUND: During ultrasound (US)-guided cannulation of the subclavian vein (SCV) via an infraclavicular route, the view of the needle behind the clavicle may be obscured. This study describes the US-guided supraclavicular cannulation of the brachiocephalic vein (BCV). METHODS: The 25 mm broadband linear array US probe was placed in the supraclavicular region to obtain a longitudinal view of the BCV beginning at the junction of the internal jugular vein and SCV. Using the in-plane technique, the needle was directed under US guidance into the BCV. RESULTS: Forty-two cannulations in 35 patients (aged 26 months-8 yr, weight range 0.96-21 kg) were included. Central venous catheter placement was successful in all children. In 31 patients (73.8%), the BCV was successfully punctured on the first attempt, in six patients (14.2%) after two attempts, and in five patients (11.9%) after three attempts. Significantly more puncture attempts were needed in the smaller weight and younger children, whereas the time course of the study had no significant impact on the success rate. CONCLUSIONS: This US-guided method offers a new possibility for central venous line placement in small children. It provides good needle guidance without any disturbing US shadow caused by bony structures.

Analysis of risk factors influencing the development of severe dizziness in patients with vestibular schwannomas in the immediate postoperative phase.

OBJECTIVE: Dizziness, a common postoperative symptom in patients with vestibular schwannomas (VSs) has a negative effect on the course of recovery, particularly in patients with severe symptoms. Reports on incidence and possible risk factors contributing to these symptoms are inconsistent and sometimes even contradictory. In order to establish a profile of patients at risk of severe symptoms in the immediate postoperative phase we retrospectively analyzed data of patients with unilateral VSs focusing on the incidence of severe dizziness and nausea during the immediate postoperative period and up to 1 year after surgery. METHODS: In a retrospective study data of 104 consecutive patients with VSs were analyzed. All patients underwent microsurgical tumor resection via a lateral-suboccipital approach. Factors that were assumed to affect the development of severe dizziness, such as age, gender, tumor size, tumor side, and cranial nerve function, were analyzed by means of univariate and multivariate logistic regression analyses. A three step grading system was used to describe symptoms of patients included in this study: 0=no symptoms of dizziness, 1=slight dizziness including light-headedness or feeling of disequilibrium and 2=severe dizziness with nausea including imbalance or insecurity when walking, requiring antiemetic treatment. RESULTS: Data of 92 patients, 41 men and 51 women, were available for analyses. Mean age of treated patients was 53 years (range 17-81). There was no predilection of side (52.2% right/47.8% left). Before surgery 39 patients (42.4%) were symptom free (grade 0), 13 patients (14.1%) had slight symptoms (grade 1) and 40 patients (43.5%) suffered from severe symptoms (grade 2). Immediately after surgery two patients (2.2%) where symptom free (grade 0), 19 patients (20.7%) had slight symptoms (grade 1) and 71 patients (77.2%) suffered from severe symptoms (grade 2). All patients with grade 2 symptoms required antiemetic treatment ranging between 1 and 10 days (mean 4 days). Logistic regression analyses showed young age, large tumor size (T3/T4), female gender, and severe preoperative symptoms to be main factors increasing the odds for patients to develop severe symptoms postoperatively. CONCLUSION: Patients at risk to develop severe symptoms should receive antiemetic treatment even before surgery. If in doubt about the actual risk for a specific patient with a large tumor (T3 or T4) available data suggests that patients will benefit if antiemetic treatment is started early, even before surgery.

Topography of the lumbar sympathetic trunk in normal lumbar spines and spines with spondylophytes.

BACKGROUND: Degenerative processes of the lumbar spine may change the position of the sympathetic trunk which might cause failure of sympathetic blocks owing to inadequate distribution of local anaesthetic. METHODS: The retroperitoneal spaces of 56 cadavers [24 males and 32 females; 79 (10) yr] embalmed with Thiel's method were investigated by dissection. The course of the lumbar sympathetic trunk (LST) was documented from the diaphragmatic level to the linea terminalis. Topography of the large vessels and the psoas muscle was documented. In the case of spondylophytes, the location or direction of displacement of the trunk was regarded with special interest. RESULTS: The LST entered the retroperitoneal space at the level of the vertebral body of L2 in 70 of the 112 sides and showed the most consistent relationship with the medial margin of the psoas muscle at intervertebral disc level L2/3. On 11 spines with spondylophytes, the sympathetic trunk was dislocated to the most ventrolateral point of the spondylophyte in 12 cases, in six cases dorsolaterally, and in one case ventromedially. The more the sympathetic chain departed at the vertebral body level, the more the body developed a concavity by loss of height. CONCLUSIONS: Spondylophytes influenced the location of the LST and the distribution of the local anaesthetic. The local anaesthetic should wash around the spondylophyte to reach all possible locations of the chain. The medial margin of the psoas muscle was confirmed to be a consistent reference point at intervertebral disc level L2/3.