Variation of a Persistent Primitive Hypoglossal Artery (PPHA) as Incidental Finding in the Diagnostic Clarification of Cerebral Vasculopathy Associated with Intracranial Vasculitis.

We present a very rare variation of a persistent primitive hypoglossal artery (PPHA) arising from the internal carotid artery, detected during a diagnostic angiography. A 50-year-old female patient was admitted with an atypical intracranial hematoma in the left frontal lobe. Catheter angiography revealed intracranial vasculopathy with segmental stenoses, a small aneurysm of the right internal carotid artery bifurcation and a "string of beads" appearance of the left carotid artery, consistent with fibromuscular disease. On the left side, a vertebral artery ending in the posterior inferior cerebellar artery (PICA) was detected, whereas on the right side the vertebral artery was aplastic. During selective angiography of the right common carotid artery, a persistent hypoglossal artery was seen supplying the basilar artery. The literature of persistent embryonal carotid-vertebrobasilar anastomosis and their anatomical variations is discussed with respect to clinical importance for ischemia, interventional procedures, and surgery.

Unusual spinal metastases from an adenoid cystic carcinoma of the maxillary sinus.

Adenoid cystic carcinoma (ACC), the second most common cancer occurring in the sinonasal tract, is an aggressive malignancy with a poor five-year survival rate. Spinal metastases to the vertebral column related to this cancer are rare. This report presents a patient with maxillary sinus carcinoma with vertebral metastases at the thoracic level and compression of the spinal cord seven years after surgical resection of the primary tumor. Eleven years after detection of the primary tumor the patient is still able to walk. The role of decompression and/or fusion in spinal metastases with neurologic deficits is still under debate, although recent studies have confirmed the beneficial role of surgical intervention in selected patients. This report represents an example of modern individual treatment of an aggressive tumor in a palliative situation. The epidemiology, clinical findings, treatment and outcome of this atypical distant metastasis in long-term survivors are presented.

Translaminar screws of the axis--an alternative technique for rigid screw fixation in upper cervical spine instability.

C2 pedicle screws or transarticular atlantoaxial screws are technically demanding and carry an increased risk of vertebral artery injury. In up to 20% of cases, pedicle and transarticular screw placement is not possible due to a high-riding vertebral artery or very small C2 pedicles in addition to other anatomical variations. Translaminar screws have been reported to rigidly capture posterior elements of C2 and therefore appear to be a suitable alternative. We present our first experiences and clinical results with this new method in two neurosurgical spine centers. Twenty-seven adult patients were treated between 2007 and 2010 in two neurosurgical spine departments with C2 translaminar screw fixation for upper cervical spine instability of various origins (e.g., trauma, tumor, dens pseudarthrosis). Eight patients were men and 19 were women. Mean age was 68.9 years. In most cases, translaminar screws were used because of contraindications for pedicle or transarticular screws as a salvage technique. All patients were clinically assessed and had CT scans postoperatively to verify correct screw placement. Follow-up was performed with reexamination on an ambulatory basis. Mean follow-up was 7.6 months for all patients. In 27 patients, 52 translaminar screws were placed. There were no intraoperative complications. Postoperatively, we identified four screw malpositions using a new accuracy grading scale. One screw had to be revised because of violation of the spinal canal >4 mm. None of the patients had additional neurological deficits postoperatively, and all showed stable cervical conditions at follow-up. Two patients died due to causes not associated with the stabilization technique. The fusion rate for patients with C1/C2 fixation is 92.9%. Translaminar screws can be used at least as an additional technique for cases of upper cervical spine instability when pedicle screw placement is contraindicated or not possible. The current data suggest comparable biomechanical stability and fusion rates of translaminar screws to other well-known posterior fixation procedures. In addition, translaminar screw placement is technically less demanding and reduces the risk of vertebral artery injury.

[Atypical dislocated dens fracture type II with rotational atlantoaxial luxation after a riding accident]. / Atypische dislozierte Densfraktur Typ II mit rotatorischer atlantoaxialer Luxation nach Reitunfall.

We present a rare case of a combined dislocated odontoid dens fracture type II (Anderson/D'Alonzo) and rotational atlantoaxial luxation in a 15-year-old girl who was involved in a riding accident.She fell off her horse after it had stopped suddenly, losing consciousness for a few minutes. At presentation in the hospital, she had no complaints other than limited, painful neck movement. Radiologically, a posterior dislocation of an odontoid type II fracture (Anderson/D'Alonzo) was found. Computed tomography reconstruction demonstrated a rotational, hooklike fixed luxation of the left atlantoaxial facet joint. Manual repositioning after application of a cervical collar failed. Therefore, operative treatment was indicated for this highly unstable fracture. Posterior transarticular atlantoaxial screw fixation according to Magerl was performed; an iliac corticocancellous bone graft was harvested and shaped to conform to the posterior processes of C1 and C2. Additionally a hook-claw atlas fixation of C1 was done.To our knowledge, this is the first case of adolescent atlantoaxial cervical spine trauma in combination with an odontoid fracture and fixed rotational luxation reported in literature.

Neurosurgical management of previously coiled recurrent intracranial aneurysms.

OBJECTIVE: Endovascular treatment of cerebral aneurysms with detachable coils has proven to be a save and effective treatment. But long-term recurrence due to aneurysm regrowth or coil compaction has been reported in up to thirty percent of cases. Therefore a growing number of previously coiled aneurysms have to be retreated by coiling or, in some circumstances, by clipping. We present a consecutive series of ten patients who underwent surgical clipping for recurrent aneurysms after primary coil embolization. METHODS: During a 4-year period ten patients with intracranial aneurysms previously treated by coil embolization underwent surgery for clipping of recanalized aneurysms. All aneurysms were located in the anterior circulation (internal carotid artery [ICA], 2; middle cerebral artery [MCA], 3; anterior communicating artery [AcomA], 5). Clinical data and imaging studies of the patients were analyzed retrospectively. RESULTS: All recurrences were detected by routine control angiograms within a median period of 14 months after primary treatment. In three aneurysms treated for SAH dense arachnoid scarring around the aneurysm sac was noted. In four cases, coils were found intraoperatively to be extruding through the aneurysm sac into the subarachnoid space. Each aneurysm could be clipped without affecting the perfusion of the parent vessel. In one patient the aneurysm sac including the coil package was resected. In one patient one of the central anteromedial arteries was injured during dissection due to dense arachnoid scarring because of prior SAH. As a consequence infarction of the head of the caudate nucleus without neurological compromise was observed on follow-up CT scans. Another patient developed transient aphasia due to vasospasm in the early postoperative period with complete restitution. In the end all patients had an uneventful recovery. Removal of the coil package was not necessary in most cases. Clipping of the aneurysm neck was possible even in cases with coil dislocation into the parent vessel. CONCLUSION: Clipping of previously coiled aneurysms is a unique problem for vascular neurosurgeons. In most cases clipping is feasible. Clipping should still be considered as a definite treatment option in previously coiled recurrent aneurysms. Results in this small series were good.

Complications of transpedicular screw fixation in the cervical spine.

Today, posterior stabilization of the cervical spine is most frequently performed by lateral mass screws or spinous process wiring. These techniques do not always provide sufficient stability, and anterior fusion procedures are added secondarily. Recently, transpedicular screw fixation of the cervical spine has been introduced to provide a one-stage stable posterior fixation. The aim of the present prospective study is to examine if cervical pedicle screw fixation can be done by low risk and to identify potential risk factors associated with this technique. All patients stabilized by cervical transpedicular screw fixation between 1999 and 2002 were included. Cervical disorders included multisegmental degenerative instability with cervical myelopathy in 16 patients, segmental instability caused by rheumatoid arthritis in three, trauma in five and instability caused by infection in two patients. In most cases additional decompression of the spinal cord and bone graft placement were performed. Pre-operative and post-operative CT-scans (2-mm cuts) and plain X-rays served to determine changes in alignment and the position of the screws. Clinical outcome was assessed in all cases. Ninety-four cervical pedicle screws were implanted in 26 patients, most frequently at the C3 (26 screws) and C4 levels (19 screws). Radiologically 66 screws (70%) were placed correctly (maximal breach 1 mm) whereas 20 screws (21%) were misplaced with reduction of mechanical strength, slight narrowing of the vertebral artery canal (<25%) or the lateral recess without compression of neural structures. However, these misplacements were asymptomatic in all cases. Another eight screws (9%) had a critical breach. Four of them showed a narrowing of the vertebral artery canal of more then 25%, in all cases without vascular problems. Three screws passed through the intervertebral foramen, causing temporary paresis in one case and a new sensory loss in another. In the latter patient revision surgery was performed. The screw was loosened and had to be corrected. The only statistically significant risk factor was the level of surgery: all critical breaches were seen from C3 to C5. Percutaneous application of the screws reduced the risk for misplacement, although this finding was not statistically significant. There was also a remarkable learning curve. Instrumentation with cervical transpedicular screws results in very stable fixation. However, with the use of new techniques like percutaneous screw application or computerized image guidance there remains a risk for damaging nerve roots or the vertebral artery. This technique should be reserved for highly selected patients with clear indications and to highly experienced spine surgeons.

[Neurogenic thoracic outlet syndrome. Long-term results of supraclavicular decompression]. / Neurogenes Thoracic-outlet-Syndrom. Langzeitergebnisse der supraklavikulären Dekompression.

OBJECTIVES: Neurogenic thoracic outlet syndrome (TOS) is one of the most controversial entrapment syndromes of the upper extremity. There are two different surgical approaches for its primary surgical treatment: supraclavicular decompression and transaxillary first rib resection. The aim of this study was to evaluate long-term results and surgical risks of the former. METHODS: This retrospective long-term study examines a series of 50 supraclavicular decompressions in 45 patients. Follow-up was for at least 24 months. All patients were reexamined regularly in nonstandardized fashion. Finally, each patient underwent a telephone interview with a standardized questionnaire. RESULTS: There was a significant deterioration of primary results during follow-up. About 30.0% of cases worsened within 24 months after operation. In the long run, about 80.0% of cases showed improvement of symptoms (26.0% excellent, 36.0% good, 18.0% moderate). The complication rate was 4.0%. CONCLUSION: Due to secondary deterioration of treatment during follow-up, only long-term studies are suited for the examination of neurogenic TOS. Results after supraclavicular decompression are satisfactory, and the complication rate is low.

[Results of simple fragment excision in lumbar disc surgery]. / Ergebnisse der alleinigen Sequestrektomie bei lumbaler Bandscheibenoperation.

BACKGROUND: While performing microsurgical disc excision, usually the sequestrated disc fragments as well as loosened or degenerated parts of the nucleus pulposus are removed. It is controversial whether this strategy is always necessary. The aim of this study was to examine this question based on clinical results. MATERIAL AND METHODS: Prospectively all relevant data from 149 consecutive patients after sequestrectomy were collected including the clinical course of the patients with a mean follow-up of 2.3 years. A detailed analysis of the actual pain status, the functional capacity and possible additional spinal operations was performed. RESULTS: During early follow-up, there was one superficial wound infection, which was treated conservatively. The success rate, as measured by patient self-assessment, was 62% for excellent and good and 25% for fair results; 13% of the patients treated declared a poor result having no benefits from surgery. The average FFbH score during follow-up was 74% (100% means no functional restriction). Radicular pain and low back pain had the same intensity on the average, in contrast to some other investigations, where low back pain was lower than radicular pain [14]. Of the 149 patients, 4 underwent a second spine surgery at the same level, 2 of which were recurrent disc herniations (=1.3%). CONCLUSION: Simple fragment excision revealed similar results compared to standard microdiscectomy. There was an especially low number of recurrences in contrast to former reports [16]. This was probably caused by the conscientious selection of patients for sequestrectomy according to well-defined criteria. Whether simple sequestrectomy can effectively treat an additional low back pain component must be clarified by further prospective studies.

[Spinal intramedullary tumors. When is surgical treatment indicated?]. / Spinale intramedulläre Tumoren Wann ist die operative Behandlung angezeigt?

OBJECTIVE: Timing of surgery in patients with intramedullary tumors is the subject of controversy. The aim of this retrospective study is to evaluate whether patients with intramedullary ependymomas and astrocytomas have a better postoperative prognosis without or with slight preoperative deficits than those with severe preoperative neurological disturbances. PATIENTS AND METHODS: During a period of 8.5 years (January 1992-August 2000), 34 patients with intramedullary tumors underwent surgery in our Neurosurgical Department. Among them there were five astrocytomas WHO grade II and ten ependymomas WHO grade II. Recurrences were observed in two patients with astrocytomas and one patient with ependymoma. Pre- and postoperative functional performance was classified according to the McCormick scale in grade I-IV (grade I: neurologically normal or mild focal deficit and grade IV: severe neurological deficits and without functional independence). The follow-up period varied from 4 to 76 months (mean: 27.9 months). RESULTS: All seven grade I patients remained unchanged after surgery. Two of four grade II patients improved to grade I; two deteriorated to grade III. Two of three grade III and IV patients remained unchanged and another one deteriorated from grade III to IV. CONCLUSION: At the best, intramedullary astrocytomas and ependymomas should be operated when symptoms are mild. Early surgery can achieve good functional outcome.

[Iatrogenic nerve injuries. Part 1: Frequency distribution, new aspects, and timing of microsurgical treatment]. / Iatrogene Nervenverletzungen. Teil 1: Häufigkeitsverteilung, neue Aspekte und Zeitraster der mikrochirurgischen Versorgung.

OBJECTIVE: The aim of this study was to analyze the number and types of iatrogenic nerve injuries operated on during a 13-year period at a relatively busy nerve center. METHOD: Retrospective analysis was done of 191 cases surgically treated because of iatrogenic nerve injuries. RESULTS: Most iatrogenic nerve injuries occurred after surgical procedures. As a rule, symptoms and signs appeared immediately after the procedure. Single nerves most often involved were the spinal accessory nerve at the neck ( n=27), most frequently after lymph node biopsy, and the median nerve in the carpal tunnel ( n=25), usually after carpal tunnel release and most frequently after endoscopic technique. Following in frequency are the common peroneal nerve ( n=16), superficial sensory radial nerve ( n=13), genitofemoral ( n=12), and superficial peroneal and tibial nerves ( n=9 each). Clinical improvement after neurosurgical intervention appeared in 70% of cases. Frequently iatrogenic nerve lesions are referred with significant delay, that is, not during a time interval deemed appropriate for surgical intervention. CONCLUSION: Iatrogenic nerve lesions must be recognized in a timely manner and should be operated upon as early as other traumatic nerve injuries to ensure best chances for successful recovery.

Surgical therapy of symptomatic arachnoid cysts - an outcome analysis.

BACKGROUND: Arachnoid cysts may present with various symptoms and in different locations. Optimal treatment is still controversial, although cyst fenestration or shunt insertion are recognized as standard procedures. In this retrospective analysis the authors sought to determine which factors influence the outcome after surgery of symptomatic arachnoid cysts. METHODS: 37 patients (24 male, 13 female, mean age 40.2 years) were treated within a ten year period in our institution. Mean follow-up was 39 months; follow-up was done on an ambulatory basis. For analysis patient charts were reviewed and cranial CT scans or MR investigations were examined to determine pre- and postoperative cyst volumes. Clinical outcome was graded into four subgroups using a scale based on the patients self-rating of success. Different factors were studied concerning their influence on outcome. FINDINGS: Fenestration was performed in 28 cases, cysto-peritoneal or cysto-atrial shunting in 9 cases. A favourable outcome (subgroups 3 and 4) was achieved in 19 of 28 patients (fenestration) and in 6 of 9 patients (shunting), respectively. Mean reduction of the cyst volumes was 58% after fenestration and 74% after shunting revealing both methods to be effective. Degree of cyst volume reduction correlated significantly with clinical outcome. Patients with infratentorial cysts had more often a favourable outcome. Headache as the only symptom did not influence outcome. CONCLUSIONS: Surgery of symptomatic arachnoid cysts resulted in favourable outcome in two thirds of the patients. Both standard procedures, fenestration and shunting, are equally effective for treatment. Factors that influence outcome are the rate of volume reduction and cyst location.

Percutaneous transarticular atlantoaxial screw fixation using a cannulated screw system and image guidance.

In 2000 a cannulated screw stabilization system for posterior cervical instrumentation was introduced in our department for use in complex cervical fixation procedures. A special feature of the system is the use of thin Kirschner wires for drilling the screw paths and then placing the self-drilling, cannulated screws securely over the wires. Percutaneous application of C1-C2 transarticular screws is possible through tubes. An optional "atlas-claw" provides additional stability in cases of C1-C2 stabilization. 17 patients (10 female, 7 male, mean age 60 years) with complex cervical disorders and instability of different origin were stabilized using the Neon System (Ulrich Co., Ulm, Germany). Pathology included atlantoaxial instability based on rheumatoid arthritis (n = 12), odontoid fracture (n = 4) and os odontoideum mobile (n = 1). Computed navigation (STN 4.0, Zeiss or vector vision spine, brain lab) was used in 14 cases. Transarticular C1-C2 screw fixation was performed in 14 cases (4 patients with direct C1 massa lateralis screw fixation), craniocervical fixation (C0-C2/C3) was done in 3 patients. Percutaneous application of the C1-C2 screws was used in 7 patients. Atlas claws were applied in 8 patients. There was one medial perforation of a C2 pedicle wall and one malposition of the screw in C2 without reaching the lateral mass of C1. After a mean follow-up of 9 months there were no hardware failures and stable fusion in those cases followed after 12 months or more. Clinical results were excellent or good in 14/16 patients. Cannulated screws are an effective alternative in complex stabilization procedures of the cervical spine. The presented system is technically comfortable and allows safe percutaneous screw application as well as inclusion of computed navigation with high accuracy.

[Pitfalls of endoscopic carpal tunnel release]. / Iatrogene Nervenverletzungen Teil 2: Fallstricke der endoskopischen Karpaltunneloperation-Folgerungen aus den Befunden offener Revisionsoperationen.

BACKGROUND: The objective of this study was to evaluate the causes of failed endoscopic carpal tunnel release (CTR) in order to detect potentially hazardous operative steps. The intraoperative findings of 10 microsurgically revised cases were retrospectively analyzed. RESULTS: From January 1999 to October 2001, ten patients underwent open revision surgery after being referred because of failed endoscopic carpal tunnel release (CTR). The median nerve had been injured in five cases, necessitating autologous sural nerve grafting in four. Two other patients underwent extensive (external and internal) neurolysis. The lesions were located twice in the main nerve trunk, three times in the recurrent motor branch, three times in a digital nerve, and once in the sensory palmar branch. The transverse carpal ligament (TCL) had not been sectioned in four cases and was incomplete in two. In another two cases, previously sectioned TCLs were closed again by firm fibrous tissue. In three cases, postoperative hematomas after the initial release were described and possibly contributed to symptoms. CONCLUSION: Endoscopic CTR in the hand of the inexperienced bears major risks for iatrogenic neurovascular injury.

Approach-related complications of transthoracic spinal reconstruction procedures.

Direct surgical repair of instabilities of the anterior spinal column has gained in importance. New techniques and instruments have led to better operative results. Inspite of the growing number of interventions at the anterior spinal column only little data is available on the typical intra- and postoperative complications of these anterior approaches Between 4/1998 and 8/2002, 85 patients in two neurosurgical centres were treated using an anterolateral transthoracic approach for various lesions of the thoracic and thoracolumbar spine. We used a minithoracotomy with video-endoscopic guidance in 75 of these patients. Intra- and postoperative complications were evaluated retrospectively. Two operations had to be abandoned, in all other cases surgery was performed as planned. Postoperatively, eleven patients complained of temporary intercostal neuralgia (12.9%), two patients (2.3%) had a pulmonary insufficiency which was treated conservatively, another patient needed drainage of a pleural effusion. One intraoperative injury to the thoracic duct was treated conservatively, one hernia of the abdominal wall had to be corrected surgically. Relevant injuries to the vessels did not occur, blood loss was 520 ml on average. There was no surgical mortality; one revision surgery had to be performed because of bone graft dislocation. The rate of severe approach-related complications was 4/85 = 4.7% (two abandoned procedures, one injury to the thoracic duct, one abdominal hernia). Transthoracic anterolateral stabilisation via a minithoracotomy with video-endoscopic guidance is an effective surgical approach to treat instabilities of the anterior parts of the thoracic spine and the thoracolumbar area with low complication rates.

First clinical experiences with a new cervical fixation device - technical report.

In a first clinical series of ten patients the new cervical fixation device StarLock trade mark (Synthes, Umkirch, Germany) was implanted.[nl]Characteristics of the device are deep threaded screws with higher pullout resistance and a high angular tolerance while inserting the rods thus simplifying the implantation.[nl]62 lateral mass screws in ten patients were inserted. In 2 cases placement of screws was insufficient (3.2 %) because of surgical difficulties not attributable to the system technique.[nl]In all other cases a radiologically proven stabilization was created. [nl]Due to the high angular tolerance of the screw clamps bending of rods is simplified, especially in cases of longer constructs, and shortens the operation time.[nl]The design of the StarLock trade mark system allows an easy application of computer-navigated placing of transpedicular screws.[nl]This new cervical fixation device is easy to handle and simplifies rod application especially in longer constructs.

Nocardia brain abscess misinterpreted as cerebral infarction.

We present the case of a non-immunocompromised man with right-sided hemiparesis and aphasia thought to be caused by cerebral infarction, but which in the later clinical course evolved to be a nocardia brain abscess that needed surgical intervention. Misinterpretation of imaging combined with the absence of clinical signs of infection led to inadequate primary treatment

Treatment of chronic subdural haematoma with percutaneous needle trephination and open system drainage with repeated saline rinsing.

Fifty three patients with symptomatic chronic subdural haematomas were treated with single needle trephination followed by open system drainage with repeated saline rinsing for two days. After single trephination good outcome was achieved in 84% of the patients. Early recurrence was found in 11.3% of the cases. After a second needle trephination good outcome increased to 89%. Mortality rate was 4%. Long term follow up (mean 30 months) showed 6.7% recurrence rate. There were no complications. Single needle trephination with open system drainage and repeated rinsing is an effective and safe minimal invasive procedure for patients with chronic subdural haematomas.

Collaborative study to improve the quality control of trace element determinations in polymers. Part 2. Certification of polyethylene reference materials (CRMs 680 and 681) for As, Br, Cd, Cl, Cr, Hg, Pb, and S content.

Two polymer (polyethylene) reference materials have been produced in support of EC Directive 94/62/EC on plastic packaging and packaging material. The paper describes the preparation of the materials, the analytical work performed to characterize their homogeneity and stability, and the certification of the materials for a range of elements. The technical and statistical evaluation of the results are also summarized.