Monoclonal Antibodies: What the Diagnostic Neuroradiologist Needs to Know.

Monoclonal antibodies have become increasingly popular as novel therapeutics against a variety of diseases due to their specificity, affinity, and serum stability. Due to the nearly infinite repertoire of monoclonal antibodies, their therapeutic use is rapidly expanding, revolutionizing disease course and management, and what is now considered experimental therapy may soon become approved practice. Therefore, it is important for radiologists, neuroradiologists, and neurologists to be aware of these drugs and their possible different imaging-related manifestations, including expected and adverse effects of these novel drugs. Herein, we review the most commonly used monoclonal antibody-targeted therapeutic agents, their mechanism of action, clinical applications, and major adverse events with a focus on neurologic and neurographic effects and discuss differential considerations, to assist in the diagnosis of these conditions.

Artery of Davidoff and Schechter Supply in Dural Arteriovenous Fistulas.

The artery of Davidoff and Schechter is a dural branch of the posterior cerebral artery that can supply the meninges close to the falcotentorial junction. It is usually not identified on angiography except when enlarged in the setting of a dural AVF or meningioma. The impact on treatment of the artery of Davidoff and Schechter supply to a fistula is not well-described in the literature. Our retrospective analysis of patients with dural AVFs treated at the Toronto Western Hospital between 2006 and 2018 identified 6 patients with dural AVFs receiving supply from artery of Davidoff and Schechter (of a total of 173 patients with dural AVFs). All patients were initially treated by transarterial embolization using liquid embolic agents. Three patients required a second endovascular procedure partly due to residual supply from artery of Davidoff and Schechter, and in all cases, angiographic cure was obtained. The treatment approach, challenges encountered, and potential complications of treating such fistulas are described.

Predictive Value of MRI in Diagnosing Brain AVM Recurrence after Angiographically Documented Exclusion in Children.

BACKGROUND AND PURPOSE: MRI is routinely performed following brain AVM after treatment in children. Our aim was to determine the predictive values of contrast-enhanced MR imaging and TOF-MRA for brain AVM recurrence in children, compared with conventional angiography and the role of 3D rotational angiography-MR imaging fusion in these cases. MATERIALS AND METHODS: We included all pediatric patients with brain AVMs during an 18-year period with angiographically documented obliteration after treatment. Patients underwent 3T MR imaging, including contrast-enhanced MR imaging, TOF-MRA, and conventional angiography, with a subset undergoing 3D rotational angiography. The predictive values of contrast-enhanced MR imaging and TOF-MRA for brain AVM recurrence were determined. CTA sections reconstructed from 3D rotational angiography were coregistered with and fused to 3D-T1WI for analysis. RESULTS: Thirty-nine children (10.8 ± 3.9 years of age; range, 2-17 years; male/female ratio, 19:20; mean Spetzler-Martin grade, 1.9 ± 0.6) met the inclusion criteria. Of these, 13 had angiographically confirmed brain AVM recurrence, 8 following surgery and 5 following embolization. Sensitivity, specificity, and positive and negative predictive values for recurrence were the following: contrast-enhanced MR imaging: 84.6%, 38.5%, 40.7%, 81.8%; TOF-MRA: 50.0%, 96.1%, 85.7%, 79.3%; both: 75.0%, 90.9%, 85.7%, 83.3%. 3D rotational angiography-MR imaging fused images confirmed or excluded recurrence in all available cases (13/13). Embolization-only treatment was a significant predictor of recurrence (OR = 32.4, P = .006). MR imaging features predictive of recurrence included a tuft of vessels on TOF-MRA and nodular juxtamural/linear enhancement with a draining vein on contrast-enhanced MR imaging. CONCLUSIONS: MR imaging is useful for surveillance after brain AVM treatment in children, but conventional angiography is required for definitive diagnosis of recurrence. TOF-MRA and contrast-enhanced MR imaging provide complementary information for determining brain AVM recurrence and should be interpreted in conjunction. 3D rotational angiography-MR imaging fusion increases the diagnostic confidence regarding brain AVM recurrence and is therefore suited for intraoperative neuronavigation.

Facial Venous Malformations Are Associated with Cerebral Developmental Venous Anomalies.

BACKGROUND AND PURPOSE: A number of studies have demonstrated the existence of segmental vascular disorders affecting soft tissues of the head and neck along with the intracranial vasculature. The purpose of this study was to determine whether there is an association between cerebral developmental venous anomalies and venous malformations of the face, head, and neck. MATERIALS AND METHODS: A consecutive series of patients with head and neck venous malformations who underwent MR imaging of the brain with postcontrast T1- or T2*-weighted imaging were included. Developmental venous anomaly prevalence in this patient population was compared with an age- and sex-matched control group without venous malformations at a ratio of 1:2. All images were interpreted by 2 neuroradiologists. Data were collected on venous malformation location, developmental venous anomaly location, developmental venous anomaly drainage pattern, and metameric location of venous malformations and developmental venous anomalies. Categoric variables were compared using χ2 tests. RESULTS: Forty-two patients with venous malformations were included. The mean age was 38.1 ± 11.1 years, and 78.6% of patients were female. The prevalence of developmental venous anomalies in this patient population was 28.6%. The control population of 84 patients had a mean age of 40.0 ± 5.9 years, and 78.6% of patients were female. The prevalence of developmental venous anomalies in this patient population was 9.5% (P = .01). In 83.3% of cases, developmental venous anomalies were ipsilateral to the venous malformation, and in 75% of cases, they involved the same metamere. CONCLUSIONS: Our case-control study demonstrated a significant association between brain developmental venous anomalies and superficial venous malformations. These findings suggest that there may be a similar pathophysiologic origin for these 2 entities.

Comparison of 3 Different Types of Spinal Arteriovenous Shunts below the Conus in Clinical Presentation, Radiologic Findings, and Outcomes.

BACKGROUND AND PURPOSE: Spinal arteriovenous shunts below the conus constitute 3 types of lesions, which have previously been mainly described in case reports, given their rarity, and are sometimes misdiagnosed. The purpose of this study was to describe the features of each type and compare these types as to epidemiologic features, clinical and radiologic presentations, treatment, and outcomes in a consecutive series of 48 cases. MATERIALS AND METHODS: The prospectively collected data bases of 2 referral centers for spinal vascular lesions were retrospectively reviewed. Spinal arteriovenous shunts below the conus were defined as all dural and intradural shunts below the conus medullaris. Clinical features, radiologic findings, treatment results, and clinical outcomes were assessed. RESULTS: There were filum terminale arteriovenous fistulas in 11 patients (22.9%), radicular arteriovenous shunts in 7 patients (14.6%), and spinal dural arteriovenous fistulas in 30 patients (62.5%). Radicular arteriovenous shunts presented at a younger age (P = .017) and with a higher incidence of back pain symptoms (P = .037). A tethered spinal cord was found in 54.5% of patients with filum terminale arteriovenous fistulas and 23.3% of patients with spinal dural arteriovenous fistulas. After treatment, the angiographic complete obliteration rate was 89.4% and spinal function was improved significantly (P < .001). CONCLUSIONS: Three groups of spinal arteriovenous shunts below the conus can be differentiated according to clinical and radiologic features. Filum terminale arteriovenous fistulas are frequently associated with dysraphic malformations, which may suggest a particular embryologic origin.

Neuroimaging of cerebral cavernous malformations.

Cerebral cavernous malformations (CCMs) are vascular malformations of the brain and brainstem that arise via a number of different mechanisms and can result in non-specific presentations. Therefore, medical imaging is essential in the diagnosis of these lesions and important to guide their clinical or surgical management. MRI is the modality of choice with newer protocols, such as susceptibility weighted imaging, playing an increasingly important role in the detection of CCMs. In this review we will discuss lesion structure, its proposed origins, and common lesion presentations and complications, before covering their expected appearances with different imaging modalities. We conclude with a discussion of insights about lesion behaviour acquired from advanced imaging techniques and provide a general approach to characterizing and diagnosing CCM lesions with neuroimaging.

Subcortical cystic lesions within the anterior superior temporal gyrus: a newly recognized characteristic location for dilated perivascular spaces.

SUMMARY: Cystic parenchymal lesions may pose an important diagnostic challenge, particularly when encountered in unexpected locations. Dilated perivascular spaces, which may mimic cystic neoplasms, are known to occur in the inferior basal ganglia and mesencephalothalamic regions; a focal preference within the subcortical white matter has not been reported. This series describes 15 cases of patients with cystic lesions within the subcortical white matter of the anterior superior temporal lobe, which followed a CSF signal; were located adjacent to a subarachnoid space; demonstrated variable surrounding signal change; and, in those that were followed up, showed stability. Pathology study results obtained in 1 patient demonstrated chronic gliosis surrounding innumerable dilated perivascular spaces. These findings suggest that dilated perivascular spaces may exhibit a regional preference for the subcortical white matter of the anterior superior temporal lobe. Other features-lack of clinical symptoms, proximity to the subarachnoid space, identification of an adjacent vessel, and stability with time-may help in confidently making the prospective diagnosis of a dilated perivascular space, thereby preventing unnecessary invasive management.

Value of cine phase contrast magnetic resonance imaging to predict obstructive hydrocephalus.

BACKGROUND: This is a prospective study to evaluate the role of CINE MRI to predict obstructive hydrocephalus in the preoperative work-up. PATIENTS/MATERIAL AND METHODS: A total of 16 patients with aqueductal obstruction demonstrated by CINE MRI who were undergoing ETV were included. MRI was performed preoperatively, at 3 months, at 12 months and at 24 months after surgery. Prior to the fenestration of the third ventricular floor aqueductal patency was evaluated using intraoperative ventriculography. A successful outcome was defined by using radiological and clinical criteria. RESULTS: In 8 patients with aqueductal obstruction on preoperative CINE MRI aqueductal patency was proven intraoperatively. ETV failed in all patients with intraoperatively proven aqueductal patency. Out of these 8 patients, 1 patient had no risk factors for ETV failure, 3 had 1 risk factor, 3 had 2 risk factors, and 1 had 3 risk factors. Most of the failure (6 out of 8 patients) occurred within 8 weeks of the initial procedure. A lumbar puncture was performed in these patients to avoid misinterpretation of the clinical course. CONCLUSION: The present study demonstrates that cine phase constrast MR may be a poorer choice to determine aqueductal patency compared to high resolution structural imaging. Interestingly, intraoperative ventriculography was an adjunct to better predict outcome after ETV in patients with obstructive hydrocephalus. In cases with non-conclusive preoperative imaging, postoperative decision making may be supported by the use of intraoperative ventriculography with the goal of reducing unnecessary tests and procedures. However, the analysis of the study data has to be considered as explorative. Therefore, findings should be validated with a larger patient population.

Pediatric Inflammatory Diseases. Part III: Small Vessels Vasculitis.

Central nervous system (CNS) vasculitis can affect both adults and children, but some of these occur almost exclusively in childhood. In children may develop as a primary condition or secondary to an underlying systemic disease. Cerebral vasculitis can be classified on the basis of the diameter of the involved vessels, although there is no univocal consensus. The diagnosis of CNS vasculitis is particularly difficult because the available investigative modalities have limited sensitivities and specificities. The most helpful diagnostic tests include cerebrospinal fluid analysis, MRI (MR angiography/venography (MRA/MRV) of the brain, and angiography. However, brain biopsy may be required to diagnose small vessel vasculitis in order to make differential diagnosis with a wide range of conditions, such as degenerative vasculopathies, embolic diseases, or coagulation disorders. This paper discusses on current understanding of most frequent primary and secondary central nervous system vasculitis in children in which are involved small vessel.

Myxomatous aneurysms: a case report and literature review.

Cardiac myxomas are benign tumors that may lead to neurological manifestations including ischemic stroke, aneurysms or metastases. We describe a patient with multiple intracranial aneurysms who presented with TIA-like symptoms following resection of an atrial myxoma, and review the clinical and imaging features of myxomatous aneurysms as reported in the literature. The most prominent imaging features of myxomatous aneurysms are their multiplicity, fusiform shape and distal location whereas from a clinical point of view they most often present with stroke like symptoms rather than with hemorrhage. These neurological manifestations may occur even after successful and complete surgical removal of the atrial myxoma.

Functional MR imaging in patients with carotid artery stenosis before and after revascularization.

BACKGROUND AND PURPOSE: Significant extracranial stenosis of the ICA is a known risk factor for future stroke and it has been shown that revascularization reduces the risk of future stroke. We applied BOLD fMRI in patients with carotid artery stenosis before and after CEA. Our purpose was to determine whether fMRI is able to demonstrate impaired CVR and to identify patient parameters that are associated with postoperative changes of cerebral hemodynamics. MATERIALS AND METHODS: Nineteen consecutive patients with symptomatic (n = 13) and asymptomatic (n = 6) stenosis of the ICA were prospectively recruited (male/female ratio = 16:3; age, 69 ± 8,1 years). fMRI using a simple bilateral motor task was performed immediately before and after CEA. RESULTS: Mean BOLD MSC was significantly increased postoperatively (MSC, 0.13 ± 0.66; P = 0.0002). Patients with a stenosis of <80% demonstrated an increase in MSC (MSC, 0.32 ± 0.59; P ≤ .0001). Patients with previous ischemic stroke showed a larger MSC than patients with TIAs (stroke: MSC, 0.55 ± 0.65; P ≤ .0001; TIA: MSC, 0.05 ± 0.26; P = 0.054). Patients older than 70 years had a significantly larger MSC following surgery (≤70 years: MSC, -0.01 ± 0.39; P = .429; >70 years: MSC, 0.29 ± 0.48; P ≤ .0001). CONCLUSIONS: BOLD fMRI can demonstrate changes in cerebral hemodynamics before and after CEA, indicative of an ameliorated CVR. This response is dependent on the age of the patient, the degree of preoperative stenosis, and the patient's symptoms.

Early control of distal internal carotid artery during carotid endarterectomy: does it reduce cerebral microemboli?

AIM: According to the results of the large trials on carotid endarterectomy (CEA), this type of surgery is only warranted if perioperative mortality and morbidity are kept considerably low. Less attention has been paid to methods of cerebral protection during CEA, although intraoperative transcranial Doppler (TCD) can visualise intracerebral microemboli (MES) during routine carotid dissection, although MES occur throughout the CEA, only those during dissection are related to neurological outcome. Prevention of MES by means of early control of the distal internal carotid artery dislodging from the carotid artery plaque during dissection is very likely the mechanism behind an eventual benefit from this approach. Hence, the amount of MES might serve as a surrogate parameter for the risk of periprocedural neurological events. So, the aim of the present study was to evaluate whether early control of the distal carotid artery during CEA is capable of reducing the number of MES by means of a prospective randomised trial. METHODS: Twenty-eight patients (29 procedures) could be prospectively included in our study. Before surgery we randomly assigned the patients to two groups: group A (N.=12): CEA by means of early control of the distal internal carotid artery; group B (N.=17): CEA with dissection of the total carotid bifurcation before clamping the arteries. Periprocedurally, we continuously monitored the cerebral blood flow in the ipsilateral middle cerebral artery by means of TCD. Pre- and postoperative morbidity were independently verified by a neurologist <2 days before and not later than five days after the procedure. Values of microembolic signs during dissection were summarised with arithmetic means and standard deviations. For further analysis non parametric Wilcoxon test was performed between both methods. P-values <0.05 were considered as statistically significant. Wilcoxon test was performed to compare both methods concerning clamp- and procedure times. RESULTS: We performed EEA 26 times, in three patients a longitudinal arteriotomy with endarterectomy and patchplasty was performed, in one of these patients a shunt was necessary. In 12 twelve patients MES occurred during the dissection before clamping. Eight of these patients belonged to group B and four patients to group A. The mean number of MES during dissection for group A was 2.4 (SD 4.6; 5-15) and for group B 3.9 (SD 7.1; 2-28). There is no statistically significant difference in the Wilcoxon-test; P=0.4375. There was no patient showing reperfusion syndrom or clinical signs of a new cerebral infarction or any other neurological deficit. There were no other major complications like myocardial infarction or death as well as no minor complications like periphereal nerve lesions, bleeding or wound healing disturbance. CONCLUSION: In this prospective, randomised trial early control of the distal internal carotid artery did not reduce the occurrence of MES during dissection of the carotid bifurcation. Also, the total number of MES throughout the procedure and postoperatively was comparable between both groups. The procedure related times as well as the clinical outcome did not differ significantly. Thus, early control of the distal internal carotid artery has got no advantage but also no disadvantage as compared to the traditional CEA technique. However, a limitation of the study is the small number of patients included.

Carotid plaque analysis: comparison of dual-source computed tomography (CT) findings and histopathological correlation.

PURPOSE: Plaque morphology is an important predictor of stroke risk and may also be a predictor of postoperative outcome after carotid endarterectomy (CEA). Thus, the purpose of our study was to evaluate the findings of preoperative dual-source computed tomography (DSCT) of carotid plaque morphology and correlate these findings with histopathological findings. MATERIAL AND METHODS: Thirty patients undergoing CEA due to neurological events and high-grade carotid artery stenosis were evaluated with DSCT for degree of stenosis following the North American Symptomatic Carotid Endarterectomy Trial (NASCET) criteria and for non-invasive plaque morphology prior to CEA. CT protocol was as follows (SOMATOM Definition, Siemens Medical Solutions, Forchheim, Germany): A dual-energy protocol was used with tube A (140 kV, 55 mA) and tube B (80 kV, 230 mA) with 2 x 64 x 0.6-mm collimation, pitch 0.65 and rotation time of 0.33 s. Histopathological work-up was performed on the surgically retrieved tissues. The findings from DSCT and histopathology were compared with respect to image quality and plaque composition (fatty plaque, mixed plaque and calcified plaque), were correlated with histological specimens and classified according to the American Heart Association (AHA) classification of atherosclerotic plaque. Pearson correlation and kappa statistics were performed. RESULTS: The image quality of DSCT was rated as 'excellent' in all the examinations. The mean degree of stenosis was quantified as 82%. The sensitivity of DSCT for the detection of calcification was 100% (standard deviation (SD) 0%, confidence interval (CI): 99-100). While the sensitivity for the detection of mixed plaques was 89% (SD 12%, CI: 79-98), it was 85% (SD 10%, CI: 76-92) for the detection of low-density fatty plaques. The mean degree of agreement was k=0.81. CONCLUSION: DSCT angiography of the carotid arteries is feasible and the evaluation of carotid plaque composition allows non-invasive assessment of different plaque components. This may have an impact on the non-invasive differentiation of vulnerable plaques.

Dangerous extracranial-intracranial anastomoses and supply to the cranial nerves: vessels the neurointerventionalist needs to know.

Transarterial embolization in the external carotid artery (ECA) territory has a major role in the endovascular management of epistaxis, skull base tumors, and dural arteriovenous fistulas. Knowledge of the potential anastomotic routes, identification of the cranial nerve supply from the ECA, and the proper choice of embolic material are crucial to help the interventionalist avoid neurologic complications during the procedure. Three regions along the skull base constitute potential anastomotic routes between the extracranial and intracranial arteries: the orbital, the petrocavernous, and the upper cervical regions. Branches of the internal maxillary artery have anastomoses with the ophthalmic artery and petrocavernous internal carotid artery (ICA), whereas the branches of the ascending pharyngeal artery are connected to the petrocavernous ICA. Branches of both the ascending pharyngeal artery and the occipital artery have anastomoses with the vertebral artery. To avoid cranial nerve palsy, one must have knowledge of the supply to the lower cranial nerves: The petrous branch of the middle meningeal artery and the stylomastoid branch of the posterior auricular artery form the facial arcade as the major supply to the facial nerve, and the neuromeningeal trunk of the ascending pharyngeal artery supplies the lower cranial nerves (CN IX-XII).

Intramedullary hemangioblastomas: timing of surgery, microsurgical technique and follow-up in 23 patients.

Hemangioblastomas are highly vascularised tumors of the central nervous system and account for 1.5-2.5% of all spinal cord tumors. Because of the rarity of these tumors, surgical experience is often limited and, therefore, treatment and indications for timing of surgery are discussed controversial. The authors reviewed their data of 23 consecutive patients with respect to timing of surgery, microsurgical technique, and follow-up. Clinical records of 23 consecutive patients with intramedullary hemangioblastomas who underwent first surgery in our department between 1990 and 2005 were reviewed. In three cases the tumors were localised at the craniocervical junction; four patients had a single tumor in the cervical spine, six patients multiple tumors in the cervical and thoracic spine, eight patients in the thoracic spine only, one patient in the conus region, and one patient had multiple tumors located in the thoracic and lumbar spine. In eight patients, a von-Hippel-Lindau disease (VHL) was associated. The neurological follow-up was evaluated according to the classification of McCormick. Operation was recommended to every symptomatic patient as early as possible. In asymptomatic patients with a sporadic tumor surgery was discussed for diagnostic purposes at any time. In VHL patients, surgery was recommended if tumor growth was observed on MRI in the next practicable time. All tumors were diagnosed by magnetic resonance imaging and in all cases but one a DSA was performed. All patients were treated microsurgically through a posterior approach. The tumors in the spinal cord were removed microsurgically through a partial hemilaminectomy (n = 1), a hemilaminectomy (n = 15), or laminectomy (n = 4) and at the craniocervical junction (n = 3) through a suboccipital craniotomy. During follow-up after 6 months, 18 patients remained neurologically stable (17 in McCormick grade I and 1 in McCormick grade II) and 5 patients recovered to a better status (3 from grade III to II, 2 from grade II to I). There was one complication with a CSF fistula and one recurrence/incomplete removal. Following the above-mentioned principles of microsurgical removal of intramedullary hemangioblastomas, operation is possible with a low procedure-related morbidity and can be recommended especially in VHL patients with progressive symptoms or tumor growth during follow-up. Patients without VHL most frequently require hemangioblastoma resection for diagnostic purposes and/or because symptoms prompted an imaging work-up that lead to the discovery of the tumor.

A less invasive surgical concept for the resection of spinal meningiomas.

BACKGROUND: The surgical strategy for spinal meningiomas usually consists of laminectomy, initial tumour debulking, identification of the interface between tumour and spinal cord, resection of the dura including the matrix of the tumour, and duroplasty. The objective of this study was to investigate whether a less invasive surgical strategy consisting of hemilaminectomy or laminectomy, tumour removal and coagulation of the tumour matrix allows comparable surgical and clinical results to be obtained, especially without an increase of the recurrence rate as reported in the literature. PATIENTS AND METHODS: Between 1990 and 2005, 61 patients (11 men, 50 women) underwent surgery for spinal meningioma. All patients were treated microsurgically by a posterior approach. In 56 of the 61 patients, the above outlined - less invasive - surgical technique with tumour removal and coagulation of the tumour matrix was performed. In 5 patients, dura resection and duroplasty was additionally performed. Electrophysiological monitoring was routinely used since 1996. Recurrence was defined as new onset or worsening of symptoms and radiological confirmation of tumour growth. The pre-and post-operative clinical status was measured by the Frankel grading system. RESULTS: Pre-operatively, 40 patients were in Frankel grade D, 13 patients in grade C, 6 patients in grade E and 1 patient each in grade A and B. Following surgery no patient presented a permanent worsening of clinical symptoms. All patients who initially presented with a Frankel grades A-C (n = 15) recovered to a better grade at the time of follow-up. Patients who presented with Frankel grade D remained in stable condition (n = 27) or recovered to a better neurological status (n = 13). Two patients experienced a temporary worsening of their symptoms, but subsequently improved to a better state than pre-operatively. Two (3.3%) complications (pseudomeningocele, wound infection) requiring surgery, were encountered. The pseudomeningocele developed in a patient who underwent durotomy. During the follow-up period of 2 months to 10 years (mean 31.3 months), 3 patients (5%) required surgery for symptomatic recurrence: 1 patient had 2 recurrences that occurred 4 and 7 years after first tumour removal and matrix coagulation, 1 recurrence occurred 1 year after tumour removal that was accompanied by matrix coagulation in a patient with a diffuse anterocranial tumour extension and 1 occurred 3 years after tumour removal and durotomy. Two patients showed a small recurrence on MRI during follow-up after 2 and 5 years, respectively, without any symptoms requiring surgery. CONCLUSIONS: The high rate of favourable clinical results combined with the low rate of recurrences supports our less invasive surgical concept, which does not aim for resection of the dural matrix of the spinal meningioma.

Treatment strategies and outcome in patients with non-tuberculous spinal epidural abscess--a review of 46 cases.

OBJECTIVES: Spinal epidural abscess (SEA) is a rare disease and its early detection and appropriate treatment is essential to prevent high morbidity and mortality. There are only few single-institution series who report their experiences with the microsurgical management of SEA and treatment strategies are discussed controversially. Within the last 15 years the authors have treated 46 patients with SEA. This comparatively high number of cases encouraged us to review our experiences with SEA focussing on the clinical presentation, microsurgical management and outcome. METHODS: Clinical charts of 46 cases with a spinal epidural abscess treated between 1990 and 2004 were reviewed. There were 30 men and 16 women, the age ranged between 32 and 86 years (mean: 57 years). The clinical mean follow-up was 8.5 months (range: 2-84). The clinical presentation and severity of neurological deficits were measured by the Frankel grading system on admission and on follow-up visit. RESULTS: The abscess was located in the cervical spine in 8, the thoracic spine in 17 and the lumbar spine in 21 patients. On admission 8 patients were in Frankel grade A, 7 in B, 15 in C, 8 in D and 8 in E. During follow-up 1 patient was in Frankel grade A, 1 in B, 5 in C, 13 in D and 24 in E. 37 patients underwent primary microsurgery with abscess drainage or removal of chronic granulomatous tissue. The clinical symptoms in 4 patients worsened shortly after the operation due to a compression fracture of the vertebral body (n=2) or progress of the abscess (n=2) making re-operation necessary. 9 patients with severe critical illness or without neurological deficits had primarily a CT-guided puncture for assessment of the causative organism. 3 of them needed additional surgical therapy within the hospital stay because of a new neurological deficit. All patients were immobilised and treated with antibiotics for at least 6 weeks. The mortality was 6.5%. As for complications we noted septicaemia (n=5), meningitis (n=1) and a transient malresorptive hydrocephalus (n=1). CONCLUSION: Early diagnosis, microsurgical therapy with appropriate antibiotic therapy and careful observation of patients are the keys to successful management of SEA. The goal of surgical treatment is to isolate the causative organism and to perform a decompression at the site of maximal cord compression in cases of neurological deterioration or severe pain. Instrumentation with primary fixation does not seem to be imperative. In cases of post-operative worsening, a fracture of additionally infected bony elements has to be considered and a stabilisation should be discussed on an individual basis.

Spinal vascular malformations--typical and atypical findings.

Vascular malformations of the spinal cord and its meninges are rare diseases which comprise true inborn cavernomas and arteriovenous malformations (AVM), including perimedullary fistulae, glomerular and juvenile AVMs, and presumably acquired dural arteriovenous fistulae. This article gives an overview of the imaging features on magnetic resonance imaging (MRI) and digital subtraction angiography of both typical and atypical findings to describe the wide variety of possible pathological entities encountered. Clinical differential diagnoses, the neurological symptomatology and potential therapeutic approaches of these diseases, which may vary depending on the underlying pathology, are given. Although MRI constitutes the first choice diagnostic modality for suspected spinal vascular malformations, we conclude that the definite diagnosis of the disease and thus the choice of the appropriate therapeutic approach rests on selective spinal angiography which should be performed at a specialized center. Treatment in symptomatic patients offers an improvement in prognosis. Microsurgical treatment is recommended for symptomatic spinal cord cavernomas. Dural arteriovenous shunts can either be treated by microsurgical or endovascular approaches, the former being a simple, quick and secure approach to obliterate the fistula while the latter is technically demanding. In spinal arteriovenous malformations of both the fistulous and the glomerular type, the endovascular approach is the method of first choice; in selected cases, surgery or a combined therapy may be necessary.

Segmental neurovascular syndromes in children.

The concept of segmental vascular syndromes with different, seemingly unrelated, diseases is based on the embryology of the neural crest and the mesoderm migration of cells that share the same metameric origin. Migrating patterns of these cells link the brain, the cranial bones, and the face on the same side. A somatic mutation developing in the region of the neural crest or the adjacent cephalic mesoderm before migration can, therefore, be postulated to produce arterial or venous metameric syndromes, including PHACES, CAMS, Cobb syndrome, and Sturge-Weber syndrome. Although these diseases may be rare, their relationships among each other and their postulated linkage with the development of the neural crest and the cephalic mesoderm may shed light on the complex pathology and etiology of various cerebral vascular disorders.

Extracranial vertebral artery involvement in neurofibromatosis type I. Report of four cases and literature review.

SUMMARY: Neurofibromatosis type 1 (NF-1) is one of the most common inherited diseases and as an autosomal dominant genetic disorder results from NF-1 gene mutation with 100% penetration and wide phenotypic variability. The disease can involve a wide variety of tissues derived from all three embryonic layers. NF-1 vasculopathy has been described primarily in peripheral arteries, but arteries supplying the CNS may also be involved. Of those, extracranial vertebral involvement is the commonest and most important. A series of four patients with NF-1 and vascular disease of the vertebral artery is described with a review of the pathophysiology, vascular phenotypes, their management and the pertinent literature.