[Operative Treatment for Saddle-Shaped Femoral Heads]. / Operacní resení sedlovité deformity hlavice kosti stehenní.

PURPOSE OF THE STUDY A saddle-shaped deformity of the femoral head has a poor prognosis due to rapid development of secondary changes. A new method of treatment by intra-articular anteromedial wedge reduction osteotomy (AWRO) of the femoral head may preserve the hip for the future. This study was designed to ascertain that this invasive technique was safe and effective and to confirm our hypothesis that AWRO significantly improved functional and radiological parameters of the hip joint. MATERIAL AND METHODS Patients who underwent AWRO between 2010 and 2013 were enrolled in this study. The indication criteria for the procedure included Stulberg grade V hips on AP radiographs, hinged abduction with pain, limping and a limited range of movement. Values of the Stulberg grading, capital diaphyseal index, caput-collum-diaphyseal angle and Harris hip score were recorded before and after surgery and the results were statistically evaluated using the paired t-test. The AWRO procedure was performed from the anterolateral approach after subperiosteal protection of the vessels had been ensured. The central necrotic part of the femoral head was removed, and the medial segment was mobilised and fixed to the intact lateral segment. Either a hip spica cast or bed-rest for six weeks was indicated. Full weight bearing was allowed at 3 months after surgery. RESULTS Twelve patients with an average follow-up of 55 months were evaluated. There were eight boys and four girls with an average age of 14 years at the time of surgery. The average Harris hip score improved from 54.52 before to 73.58 after surgery. The post-operative outcomes according to the Stulberg classification included one grade II hip, seven grade III hips, three grade IV hips and one grade V hip. The average capital-diaphyseal index dropped from 1.56 (1.19-1.92) to 1.28 (0.95-1.67) and the average caput-collum-diaphyseal angle increased from 134 degrees (121-143) to 140 degrees (130-155) after surgery. Avascular necrosis developed in two patients. All the differences were statistically significant. DISCUSSION Reduction osteotomies of the femoral head reported in the literature differ from the AWRO procedure used in this study in both the approach and the performance. The results presented here are in agreement with those published in the relevant literature. They showed no significant deterioration in comparison with the outcomes of our short-term study reported earlier. The outcome of treatment is related to the disease aetiology, functional parameters and previous procedures involving the hip joint. CONCLUSIONS AWRO is a salvage procedure that prolongs the longevity of joints in incongruent hips with very high morbidity. This procedure gave significantly better results in years after surgery, which confirmed our hypothesis. Level of evidence IV Key words: hinge abduction, Perthes disease, Stulberg, femoral head reduction osteotomy, avascular necrosis, arteria circumflexa femoris medialis.

Preoperative therapy of esophagogastric cancer: the problem of nonresponding patients.

INTRODUCTION: Preoperative treatment is nowadays standard for locally advanced esophagogastric cancer in Europe. Surprisingly, little attention has been paid to nonresponders so far. The aim of our retrospective exploratory study was the comparison of responder, nonresponder, and primary resected patients in respect of outcome considering the tumor entity. PATIENTS AND METHODS: From 2001-2011, 607 patients with locally advanced esophagogastric carcinoma (adenocarcinoma of the esophagogastric junction (AEG), n = 293; squamous cell cancer (SCC), n = 111; gastric cancer, n = 203) after preoperative treatment (n = 281) or primary resection (n = 326) were included. Histopathological response evaluation (Becker criteria) was available for 263. RESULTS: A total of 76/263 (28.9 %) were responders (<10 % residual tumor). There was an association of response with increased R0 resections (p < 0.001) but also with a higher complication rate (p = 0.008) compared to nonresponse and primary surgery. Mortality was not influenced. Increased R0 resections after response were confirmed in every tumor entity (AEG, p = 0.010; SCC, p = 0.023; gastric cancer, p = 0.006). Median survival was best for responders with 43.5 months [95 % confidence interval (CI), 27.9-59.1], followed by nonresponders with 24.3 months (95 % CI, 21.6-27.0) and primary resected patients with 20.8 months (95 % CI, 17.7-23.9; p = 0.002). AEG (p = 0.012) and gastric cancer (p = 0.017) revealed identical results, but in the subgroup of SCC, the survival of nonresponders (median, 11.6 months; 95 % CI, 6.9-16.3) was even worse than for primary resected patients (median, 23.8 months; 95 % CI, 1.7-46.0; p = 0.012). CONCLUSION: The histopathological response rate was low. Generally, nonresponding patients with AEG or gastric cancer seem not to have a disadvantage compared to primary resected patients, but nonresponders with SCC have a worse prognosis, which strengthens the demand for a critical patient selection in surgery for this tumor entity.

Expression of staphylococcal superantigens during nasal colonization is not sufficient to induce a systemic neutralizing antibody response in humans.

Staphylococcus aureus carriers have high-titer serum antibodies against non-enterotoxin gene cluster (egc) superantigens, whereas they lack anti-egc antibodies, suggesting different superantigen expression profiles in vivo. We measured the superantigen transcripts in S. aureus directly isolated from the nose of persistent carriers and correlated them with the superantigen-neutralizing antibody response. While neutralizing serum antibodies against the staphylococcal enterotoxins A and C (SEA and SEC) were found in carriers, antibodies against the egc-encoded staphylococcal enterotoxin-like toxin O (SElO) were rare. Surprisingly, the transcription of selo was comparable to sea and sec during nasal colonization. Thus, egc superantigens are transcribed during nasal colonization, but this is not sufficient to induce a serum antibody response.

A broad tuneable birdcage coil for mouse 1H/19F MR applications.

In this paper, we present the design and implementation of a 1H/19F volume coil for mouse body magnetic resonance (MR) imaging and spectroscopy using a high magnetic field (4.7 T). By changing the geometry of the coil rungs to include both nuclei for MR experiments, this innovative coil can be tuned over an extremely wide range of frequency. The coil, 45 mm in diameter and 55 mm in length, consists of a 12-rung birdcage-like structure. Using two types of tuning, the coil can generate a sufficiently homogeneous B1+ electromagnetic field within a working volume optimized for laboratory mouse. The first tuning involves changing the resonance frequency over a large frequency range. The electrical capacitance between the wires can be adjusted to reflect changes in the length of the coil. The second tuning comprises a habitual tuning transformer for precise detection in a narrow band. In contrast to widely used multinuclear coils, the coil presented here features only one resonance peak and can be manipulated according to the Larmor frequencies given for 1H and 19F. The coil was successfully tested using full-wave simulations of magnetic and electric field distributions under in vivo MR conditions.

[Efficiency of conservative treatment by overhead traction in developmental dysplasia of the hip]. / Úspesnost konzervativní lécby vývojové kycelní dysplazie metodou "over-head trakce"

PURPOSE OF THE STUDY: Developmental dysplasia of the hip (DDH) is a disorder affecting the development of the acetabulum, proximal femur and joint capsule. The objective of this study was to analyse the results of closed reduction by overhead traction in subluxated and dislocated hips. MATERIAL AND METHODS: In the period from 2002 to 2007, a total of 109 patients (124 hips) were treated by overhead traction. The indication criteria included adductor contracture and misalignment of the hip joint assessed as classes III A, III B or IV according to the Graf ultrasonographic classification. There were 96 (88 %) girls and 13 (12 %) boys. The left side was more frequently affected, at a ratio of 83 to 41, and bilateral DDH was found in 15 patients. Teratologic dislocations were not included in the study. The patients were divided into two groups according to age and the place of primary diagnosis. The children primarily diagnosed at our hospital Na Bulovce where placed in group 1, the patients diagnosed outside our hospital fell in group 2. The average age at the beginning of treatment was 2.2 months in the first group and 6 months in the second group. Our method of overhead traction consists of two phases. Horizontal traction is applied for two weeks in phase 1; the hips are then flexed beyond 90 degrees and gradually abducted for another 4 weeks in phase 2.The outcome of traction is examined by arthrography and a spica cast is applied in the safe zone.We observed the relation between the Graf classification and arthrograpy. The outcome of closed reduction was compared between the groups and the development of avascular necrosis was observed. The hips treated by open reduction were assessed in a different study. RESULTS The efficiency of closed reduction was 84 % in group 1 and 60 % in group 2 in which also two cases of recurrent dislocation were found. No significant differences between the Graf classification and the final arthrographic findings were recorded in either group (p ≥ 0.05). Avascular necrosis as defined by the Salter criteria was not diagnosed. DISCUSSION: Early reduction is essential to ensure normal development of the hip joint. Overhead traction therapy for misalignment of the hip joint is a safe method reducing damage to the femoral head. Its principle lies in gradual distraction of the contracted muscles and joint capsule with a concomitant change in traction direction in order to achieve a reduction manoeuvre without placing increased stress on the femoral head. CONCLUSIONS: Overhead traction is the method of choice for management of Graf's class III A, III B and IV hips. For the efficiency of treatment, an early diagnosis and a correct indication are essential. To avoid complications such as avascular necrosis, it is necessary to observe the principle of a safe zone.

[Rare occurrence of fulminant acid burn of the esophagus]. / Seltene Ursache einer fulminanten Säureverätzung des Osophagus.

Peptic ulcer due to Zollinger-Ellison syndrome is a rare entity. In this case report a 55-year-old man had a medical history of esophageal reflux, vomiting, and diarrhea for 10 years. Despite continuous medication with a proton pump inhibitor, no complete recovery from symptoms was achieved. A diagnosis of gastrinoma was at first not considered. After discontinuation of the proton pump inhibitor for only a few days, the strong stimulation of the gastrinoma led to fulminant hydrochloric acid burn of the distal esophagus with iatrogenic or spontaneous perforation at the esophagogastral junction. We describe the operative treatment as a two-stage reconstruction with colon interposition and resection of the primary tumor in the duodenum.

A water-soluble, bay-functionalized perylenediimide derivative - correlating aggregation and excited state dynamics.

The aggregation and the photophysics of a water soluble perylenediimide (PDI) derivative that features two bromine substituents in the bay positions has been probed. Non-fluorescent aggregates were found to be present at concentrations of 1.0 × 10-5 M. In situ small-angle X-ray scattering (SAXS) measurements and complementary molecular modeling showed the presence of PDI aggregates. In their singlet excited states, the PDI aggregates are characterized by distinct transient fingerprints and rapid deactivation, as revealed by pump-probe experiments on the femto-, pico-, nano-, and microsecond timescales. The product of this deactivation is a PDI triplet excited state. The efficiency of the triplet formation depends on the concentration, and hence on the degree of aggregation. Notably, for PDI concentrations in the range of the critical micelle concentration, the efficiency of intersystem crossing is close to zero. In short, we have demonstrated, for the first time, aggregation-induced formation of triplet excited states for PDI derivatives.

Development, standardization, and evaluation of NOTES cholecystectomy using a transsigmoid approach in the porcine model: an acute feasibility study.

BACKGROUND: Transluminal cholecystectomy is feasible. However, the procedure is time consuming, difficult, and poorly standardized so far. In the present study we therefore aimed to further evaluate and optimize a transsigmoid approach for cholecystectomy with minimal transabdominal assistance in the porcine model. METHODS: After a pilot series of 6 pigs, NOTES (natural-orifice transluminal endoscopic surgery) cholecystectomy was performed in a standardized manner in another 12 pigs. A transsigmoid approach was applied via a specially designed trocar (ISSA) with a double-channel gastroscope advanced into the peritoneal cavity. After identification of the infundibulum, the cystic duct and artery were closed by application of hemostasis clips. After dissection of these structures, the gallbladder was separated from the liver by electrocautery following injection of isotonic saline solution. A grasper introduced through a modified Veress needle (initially used for establishing the hydroperitoneum) and an additional transcutaneous stay suture were used to ease preparation of the gallbladder. RESULTS: Transluminal cholecystectomy was successfully performed in all animals. No serious acute complications occurred; minor bleeding in 4 out of 12 cases (1 cystic artery and 3 liver parenchyma) was successfully handled by electrocautery. Clip application to close the cystic duct and artery resulted in complete sealing. Standardization of the procedure was associated with a significant decrease in total operating time (113.3 +/- 31.8 minutes for the first 6 pigs and 73.6 +/- 17.2 minutes for the last 6 pigs). CONCLUSIONS: In pigs with a healthy gallbladder, our standardized technique of transsigmoid cholecystectomy could be performed relatively fast with acceptable complication rates at this level of evolution, as shown in these acute experiments.

Nickel release, a possible indicator for the duration of antiplatelet treatment, from a nickel cardiac device in vivo: a study in patients with atrial septal defects implanted with an Amplatzer occluder.

UNLABELLED: The present study was undertaken to evaluate the safety and release of nickel after implantation of a nickel device (Amplatzer occluder) in patients with an atrial septal defect (ASD) receiving antiplatelet therapy. METHODS: Blood and urine samples were obtained from 24 patients with ASD before occluder implantation (baseline) and during a 12-month post closure period. Antiplatelet drugs were administered for the initial 6-month period post implantation. The nickel content in the specimens was determined using electrothermal atomic absorption spectroscopy. The clinical, sonographic and magnetic resonance imaging follow-ups were carried out 1 week, 1 month, 6 months and 12 months post implantation. RESULTS: Mean baseline concentrations of nickel in serum and urine were within normal range with values of 0.6 +/- 0.2 microg/l and 3.1 +/- 1.2 microg/l, respectively. During the 6-week post closure period, the time needed for the formation of neointima on the surface of the graft, nickel levels in serum increased up to 5-fold (p < 0.01 versus baseline). Mean concentrations in serum and urine returned to baseline levels within 4-6 months post implantation. All patients showed satisfactory clinical improvements and there was no sonographic evidence of complications. CONCLUSIONS: The initial dissolution of nickel from the Amplatzer occluder is not a specific cardiovascular risk and is temporarily linked to the formation of the non-thrombogenic neointima on the surface of the graft. The antiplatelet drug regimen used (300 mg aspirin + 75 mg clopidogrel daily for 3 months in the initial phase and 100 mg aspirin daily for a further 3 months) appears to cover the period of neointima formation on the nickel device when nickel levels are significantly elevated. However, further studies in a larger number of patients and over a period greater than 12 months are needed to confirm the validity of these conclusions and to formulate definitive recommendations on the duration of the antiplatelet treatment.

Vestibular nuclear complex in the guinea pig: a cytoarchitectonic study and map in three planes.

Cytoarchitectonic and fiberarchitectonic criteria were used in the preparation of a detailed map illustrating the vestibular nuclear complex of the guinea pig. The brainstems used for this study were serially cut at 16 micron in the transverse, the sagittal, or the horizontal plane. The sections were studied after being stained alternately with a combined cell and fiber staining method and a Nissl stain. The basic cytoarchitectonic features of the four main vestibular nuclei, their extent, as well as their relationship to the surrounding structures are described. Additionally, the location, topographical features, and the cytoarchitecture of the small groups (f,g,l,x,y,z) associated with the vestibular nuclei are reported. Group f is especially well developed and easily distinguishable in the guinea pig. Furthermore, a hitherto undescribed cell cluster found dorsal to the dorsal border of the superior vestibular nucleus is presented. The results and especially the differences from the descriptions of other species are discussed.

Brainstem projection of the vestibular nerve in the guinea pig: an HRP (horseradish peroxidase) and WGA-HRP (wheat germ agglutinin-HRP) study.

We explored the course and termination of primary vestibular afferent fibers within the brainstem of the guinea pig by means of anterograde axonal transport of horseradish peroxidase (HRP) and wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP). Primary vestibular afferent fibers distribute within the entire vestibular nuclear complex, with the exception of the dorsal part of the lateral vestibular nucleus. The superior vestibular nucleus is characterized by the concentration of terminals within its central part. Although terminal labeling is weaker within the periphery, no area completely lacks primary input. The lateral vestibular nucleus can be divided into a ventral and a dorsal part; within the ventral part small and giant cells receive primary afferent fibers, whereas no significant terminal labeling occurs in the dorsal part. The medial vestibular nucleus shows the most uniform labeling, although the lateral part of its rostral third has a few more terminals than the medial half. Primary projection to the descending vestibular nucleus is widespread, although in its rostrodorsal part it is less impressive. Of the small cell groups commonly associated with the vestibular nuclear complex, only group y receives abundant primary input. Whereas group z completely lacks labeled fibers as well as terminals, single primary axons can be observed passing groups x and f. However, no terminals can be found within the borders of these two cell groups. Scanty projections can be detected within the prepositus hypoglossi nucleus, as well as within the external cuneate nucleus, the cochlear nucleus, the abducent nucleus, and parts of the reticular formation.

Carbocyanine postmortem neuronal tracing. Influence of different parameters on tracing distance and combination with immunocytochemistry.

Carbocyanines (DiI, DiA, DiO) are able to travel along membranes by diffusion and therefore have been used as postmortem neuronal tracers in aldehyde-fixed tissues. Surprisingly, detailed data on the influence of different parameters on tracing distances are still missing. This study was carried out to optimize tracing procedures and to reveal the validity of the combination of postmortem tracing with immunocytochemistry. Carbocyanine crystals were applied to the cervical spinal cord, sciatic nerves, and brachial plexuses of humans and guinea pigs. Incubation in the dark at 37C for 12-15 weeks proved optimal to achieve longest tracing distances (28.9 +/- 2.2 mm) in human and animal tissues. Longer incubation times and incubation temperatures higher than 37C did not result in longer tracing distances. No differences were evident between adult and newborn animals and between central and peripheral nervous system. The diffusion coefficient for DiI was calculated to be 2.5 x 10(-7) cm2 sec-1. After application of DiI to nerves of guinea pig extraocular muscles, DiI-positive afferent perikarya were observed in the anteromedial part of the trigeminal ganglion. These perikarya were identified by calcitonin gene-related peptide immunoreactivity (CGRP-IR). The percentage of CGRP-IR neurons after tracing was concordant with the percentage of CGRP-IR in trigeminal ganglia exclusively processed for CGRP-IR without previous postmortem tracing. These results demonstrate carbocyanines to be specific tracers for exact neuronal mapping studies. (J Histochem Cytochem 46:901-910, 1998)

Review article: The pharmacological properties and clinical use of valdecoxib, a new cyclo-oxygenase-2-selective inhibitor.

Cyclo-oxygenase-2-selective inhibitors produce less gastric damage than conventional non-steroidal anti-inflammatory drugs. Valdecoxib is a new orally administered cyclo-oxygenase-2-selective inhibitor, recently approved for use in osteoarthritis, rheumatoid arthritis and primary dysmenorrhoea in the USA. The drug has been evaluated in more than 60 clinical studies involving more than 14 000 patients and healthy volunteers. The analgesic efficacy of valdecoxib at a dose of 10 mg once daily in both osteoarthritis and rheumatoid arthritis is superior to that of placebo and similar to that of traditional non-steroidal anti-inflammatory drugs. Valdecoxib is effective in single doses of up to 40 mg for the alleviation of acute menstrual pain and has a rapid onset of action (within 30 min) and a long duration of analgesia (up to 24 h). Valdecoxib is well tolerated and has safety advantages compared with traditional non-steroidal anti-inflammatory drugs in terms of less gastrointestinal toxicity and a lack of an effect on platelet function. The incidence of adverse effects involving the kidney (fluid retention, oedema and hypertension) is similar to that of non-selective, non-steroidal anti-inflammatory drugs.

Imidazoline recognition sites and stomach function.

Radioligand binding experiments carried out in cell membranes from rat and human stomach revealed the existence of non-adrenoceptor [3H]clonidine and [3H]idazoxan binding sites and of [3H]DTG (1,2-di-(2-tolyl)guanidine) binding sites. In rat stomach, specific binding was inhibited by imidazolines and guanidines and by non-imidazoline sigma-site ligands, respectively, at different rank orders of affinity, suggesting the existence of non-I1/non-I2 [3H]clonidine binding sites, I2-imidazoline binding sites as well as sigma 2-like-sites. These sites are not directly related to a postsynaptic contractile effect on rat gastric smooth muscle or to acid release from isolated gastric glands. Finally, we demonstrated that the gastric pathogen Helicobacter pylori is able to form and to release the endogenous imidazoline receptor ligand agmatine and that considerable amounts of agmatine are present in human gastric juice. The quantities of agmatine were higher in gastric juice from H. pylori-positive than H. pylori-negative patients.

Surgical anatomy of the spinal accessory nerve and the trapezius branches of the cervical plexus.

BACKGROUND: A thorough understanding of the topographical anatomy of the spinal accessory nerve and the cervical plexus branches is a basic prerequisite for positive results when operating on the neck. OBJECTIVE: To give an exact description of the topographical and surgical anatomy of the spinal accessory nerve (SAN) and the trapezius branches of the cervical plexus. DESIGN: Anatomic analysis of the SAN and the trapezius branches of the cervical plexus. SETTING: The topographical anatomy of the SAN and the cervical plexus branches were studied in the anterior and posterior triangles of the necks of 46 perfusion-fixed human cadavers of both sexes, which ranged in age from 55 to 97 years (mean age, 83 years). RESULTS: The SAN can be identified on the posterior border of the sternocleidomastoid (SCM) muscle, 8.2 + 1.01 cm cranial to the clavicle. In 37% of cases, the SAN enters the posterior triangle of the neck dorsal to the SCM muscle, where it passes through the muscle in 63% of these cases. In the anterior triangle of the neck, the SAN crosses the internal jugular vein ventrally in 56% of the cases and dorsally in 44%. Regarding the cervical plexus, 1 trapezius branch could be found in 9% of the specimens, 2 in 61%, and 3 in 30%. None of the branches merged with the SAN medial to the anterior border of the trapezius muscle. In most cases, a tiny additional branch could be found arising from the SAN about 2 cm medial to the trapezius muscle. This branch enters the descendant part of the muscle approximately 2 to 3 cm cranial to the main nerve. CONCLUSIONS: Surprisingly, available data on topographical as well as surgical anatomy of the SAN and the trapezius branches of the cervical plexus are confusing and often wrong. The descriptions given herein can help to minimize the risk of injuring the SAN during neck surgery and preserve the additional innervation of the trapezius muscle granted by the rami trapezii of the cervical plexus.

The blood supply of the sternocleidomastoid muscle and its clinical implications.

BACKGROUND: The knowledge of the exact anatomy of the sternocleidomastoid (SCM) muscle and its nerve and blood supply must be considered a basic prerequisite for its use as a pedicle muscle flap. OBJECTIVE: To give an exact description of the courses and variability of all vessels supplying the SCM muscle. DESIGN: Anatomic analysis of all arteries supplying the SCM muscle. SETTING: The blood supply of the SCM muscle was studied by dissecting bilaterally the anterior regions of the neck of 31 perfusion-fixed human cadavers of both sexes aged 50 to 94 years (mean, 78 years). RESULTS: The blood supply to the SCM muscle can be divided into 3 parts: upper, middle, and lower. The upper third of the SCM muscle was found to be constantly supplied by branches of the occipital artery. According to their courses, these branches are categorized into types 1, 2a, 2b, and 3. The middle third of the SCM muscle receives its blood supply from a branch of the superior thyroid artery (42%), the external carotid artery (23%), or branches of both (27%). In most cases, the lower third of the muscle was supplied by a branch arising from the suprascapular artery (>80%), which has not been described until now. CONCLUSIONS: In contrast to available data, the arterial blood supply of the lower third of the SCM muscle is constantly provided by a branch of the suprascapular artery. Since the SCM muscle flap is used in reconstructive surgery of the neck, the exact knowledge of its blood supply may help to minimize the risk of flap necrosis after surgical procedures.

Projection of primary vestibular afferent fibres to the cochlear nucleus in the guinea pig.

After tracing the superior branch of the vestibular nerve and the macula sacculi by means of the neuronal tracers horseradish peroxidase (HRP) and wheat germ conjugated horseradish peroxidase (WGA-HRP), a conspicuous fibre bundle running into the cochlear nucleus could be observed. The HRP-labeled axons travel caudally through the descending vestibular nucleus, enter the cochlear nucleus at a level caudal to subgroup y and terminate at cells situated between the dorsal and posteroventral cochlear nucleus. Considering recent electrophysiological studies, it is reasonable to imply that these fibres are involved with the transduction of acoustic stimuli.

The origin of the vestibulo-cochlear projection in the guinea pig.

Previous tracer studies have revealed the sacculus to be connected to the vestibular and cochlear nuclei in the guinea pig. Due to its own innervation pattern, an anterior and posterior part of the sacculus can be distinguished. The present study investigated whether the two parts differ concerning their fiber contribution to the vestibulo-cochlear projection. After tracing the nerve of the posterior sacculus with horseradish peroxidase (HRP), the vestibulo-cochlear fibers were clearly recognizeable and showed distinct terminal labeling within the cochlear nuclei. In contrast, no terminals were identified in the cochlear nuclei after tracing the anterior sacculus. These results may further substantiate the guinea pig vestibulo-cochlear projection as a central pathway for saccular acoustic sensation.

Intraoperative electromyography for identification of the trapezius muscle innervation: clinical proof of a new anatomical concept.

OBJECTIVE/HYPOTHESIS: There is still considerable controversy among surgeons on trapezius muscle innervation. In addition, the rate of unexpected postoperative trapezius pareses is unacceptably high. Recent anatomical findings might answer most of the questions. The objective of the present study was to clinically prove the recent anatomical findings, especially the concept of the innervation of the descending part of the trapezius muscle. STUDY DESIGN: Intraoperative electromyography of the spinal accessory nerve and its branches in the posterior triangle of the neck. SETTING: Intraoperative electromyography was performed during 17 modified radical neck dissections on 14 patients of both sexes ranging in age from 44 to 68 years (mean age, 56 y). Potentials were registered through pairs of needle electrodes placed in each of the three parts of the trapezius muscle. Intraoperatively, the spinal accessory nerve and its fine cranial branch passing toward the descending part of the muscle were identified and stimulated in the posterior triangle of the neck.RESULTS Stimulation of the fine cranial branch of the spinal accessory nerve led to a clearly visible and recordable contraction in the descending part of the trapezius muscle in all patients. Stimulation of the main trunk of the spinal accessory nerve in the posterior triangle of the neck distal to the above-mentioned branching led to a clearly visible and recordable contraction in the transverse and ascending parts of the muscle. CONCLUSIONS: The results strongly support recent anatomical findings showing that, functionally, the most important descending part of the trapezius muscle is innervated by a fine single branch arising from the spinal accessory nerve in the posterior triangle of the neck. This may help to prevent more patients undergoing modified radical neck dissections from shoulder-arm syndrome.

Vascular endothelial growth factor receptor 2 (VEGFR2) expression in squamous cell carcinomas of the head and neck.

OBJECTIVES: Vascular endothelial growth factor receptor 2 (VEGFR2; Flk-1 [fetal liver kinase]/KDR [kinase insert domain containing receptor]) has been identified as a high affinity receptor for vascular endothelial growth factor (VEGF) on vascular endothelium. Head and neck squamous cell carcinomas (HNSCC) have already been shown to produce substantial amounts of VEGF. VEGFR2 is supposed to play a major role in tumor-neoangiogenesis. METHODS: We investigated 24 tumor specimens and 4 HNSCC cultured tumor cell lines for the incidence and distribution of VEGFR2 by immunohistochemistry using monoclonal antibodies (mAbs) and RT-PCR. RESULTS: Analysis of frozen sections by immunohistochemistry showed that in 90% of tumor specimens VEGFR2-positive cells were found which were associated with vascular endothelium. VEGFR2 was also expressed on tumor cells and vessels, which was confirmed by double immunolabeling of tumor cells with an a-cytokeratin mAb. Furthermore, 2 (JPPA, SCC9) of 4 HNSCC cultured tumor cell lines revealed positive VEGFR2 immunoreactivity. Synthesis of VEGFR2 mRNA on all 4 HNSCC cultured tumor cell lines (JPPA, SCC9, SCC25, and LFFR) and in 6 tumor specimens was confirmed by RT-PCR. In conclusion, our results showed that VEGFR2 is expressed in HNSCCs on tumor cells. VEGFR2 expression is associated with the beginning of vasculogenesis represented by accumulation of VEGFR2-positive cells budding into new vessels ("hot spots"). The focal expression pattern of VEGFR2 on tumor cells suggests an autocrine loop for VEGF in tumor cell growth.