Mehran Mahvash

Glioblastoma of the cerebellum and brainstem

Glioblastoma multiforme (GB) is the most common and most malignant primary intracranial tumor. Of the 577 patients who underwent surgery for newly diagnosed GB (World Health Organization grade IV) between January 1991 and March 2008 at our department, seven had infratentorial GB (iGB) (incidence 1.2%). Patients younger than 21years of age, as well as patients with gliomatosis cerebri, were excluded from the analysis. We concluded that iGB is rare in adults. Because of its rarity and the non-specific radiological features of iGB, it can easily be misdiagnosed as a brain metastasis, ependymoma or even as a benign lesion such as vestibular schwannoma or meningioma. Surgical removal, or at least stereotactic biopsy, is essential to establish the diagnosis. Postoperative adjuvant therapy similar to that for supratentorial glioblastoma is indicated. We analysed the clinical characteristics and therapy of our patients with iGB and reviewed the literature.

Glioblastoma Multiforme in Children: Report of 13 Cases and Review of the Literature

We present clinical and histopathologic data from 13 children who underwent craniotomy for newly diagnosed glioblastoma multiforme. Clinical characteristics were compared to those in adult patients (n = 403). The mean age of the children was 10.4 years. The male/female ratio was 3.3:1. The localization was infratentorial in 6 cases (brainstem, n = 4; cerebellum, n = 2) and supratentorial in 7 cases (frontal, n = 2; parietal, n = 3; temporal, n = 2). Infratentorial localization was observed solely in children from 0-10 years, whereas supratentorial location was found in children between the age of 11 and 21 years. Surgical resection was followed by radiotherapy in 11 cases and additional chemotherapy in 8 cases. Giant cell glioblastoma multiforme was found in 2 cases (15%, vs 1-5% in adults). The mean Ki-67 proliferation index was 29.4% (vs 25.6% in adults). There were no significant differences in histologic morphology between children and adults. The total survival time was 90 weeks (vs 47 weeks in adults). One patient is still alive after 8 years. Predictive factors of prolonged survival were the extent of tumor resection and radio- and/or chemotherapy after resection. Multidisciplinary treatment of glioblastoma in childhood might lead to better median survival than in adults. Infratentorial tumor location was observed exclusively in children younger than 11 years old.

Visualization of small veins with Susceptibility-Weighted Imaging for stereotactic trajectory planning in Deep Brain Stimulation

Intracerebral hemorrhage (ICH) is the most significant complication of Deep Brain Stimulation (DBS). To prevent ICH, stereotactic contrast enhanced T1-weighted images are used to visualize vessels as source of hemorrhage. Susceptibility-Weighted Imaging (SWI) is an MRI sequence with improved visualization of susceptibility differences between tissues, particularly sensitive for brain veins. The aim of this prospective study was to analyze the utility of SWI compared to contrast enhanced stereotactic T1-weighted images for trajectory planning of DBS. Preoperative SWI was performed in 33 patients undergoing DBS and was compared to the T1-weighted images. Vessels identified only with SWI in relation to the bilateral planned trajectory were analyzed. In all patients vessels were depicted on SWI only within the planned trajectory (range 1-4 vessels, for each trajectory, mean: 2.4). In 6 patients vessels were identified on SWI adjacent to the target (up to 5mm distal from target). In 11 patients SWI visualized additional cortical veins adjacent to the entry point of the trajectory. The apparent diameter of these vessels ranged between 0.8 and 2.1mm (mean: 1.2mm). Postoperative MRI was compared with preoperative SWI and revealed in two patients small (<3 mm) T2 hyperintense lesions along electrodes without correlation with visualized veins. SWI facilitates the visualization of small veins superior to T1-weighted images. However, cerebral veins within the trajectory were not found to be a significant source of ICH after DBS. Potential sources of ICH are mesencephal veins at the endpoint of electrodes which can cause fatal hemorrhage and are visualized with SWI reliably.

Functional magnetic resonance imaging of motor and language for preoperative planning of neurosurgical procedures adjacent to functional areas

OBJECTIVE Functional magnetic resonance imaging (fMRI) for motor and language mapping is used for presurgical planning. This study aimed to evaluate the value of fMRI in clinical routine for preoperative planning of brain surgery adjacent to functional brain areas. METHODS Thirty-seven consecutive patients with brain lesions adjacent to sensomotor and/or language functional areas underwent fMRI prior to planned brain surgery on a 3T MRI scanner for identification of motor in all and language functional areas in 29 patients. Analysis software installed on the MRI console was used for rapid image analysis and direct visualization. All fMRI results were analyzed according to the use for preoperative planning. RESULTS fMRI data analysis and visualization was possible in less than 10min. In 35 patients fMRI of motor cortex and in 25 patients fMRI of language could be performed due to the patients compliance. In 34 patients motor activity could be clearly identified in the precentral gyrus. The dominant hemisphere could be identified clearly in 22 cases. In 18 patients direct anatomical correlation of the activity maps to the speech area of Broca and/or Wernicke could be made. Resection surgery was performed in all patients. 11 patients underwent awake surgery with intraoperative cortical stimulation. CONCLUSION fMRI for clinical routine is a reliable and rapid method for identification of functional brain areas prior to brain surgery adjacent to functional areas. This method allows direct monitoring of the data quality and visualization without being time consuming. Knowledge about the relation of functional areas to the brain lesions improves the preoperative planning, the operation strategy and decision making with patients.

How did air get into the brain? A case of intracranial air in a patient without skull fracture

Dear editor, We present a rare case of a patient with air in the cavernous sinus and the craniocervical junction without evidence of skull fracture. A 62-year-old male patient fell from a bar chair and slightly hit his head. He did not lose consciousness and had no neurological symptoms. There were no signs of CSF leakage. We performed a cranial and cervical spine CTscan, and there were no traumatic signs, bleeding, fractures in the skull or skull base, or infection. Despite the absence of any trauma in the cranium and cervical spine, air was identified in the cavernous sinus and in the craniocervical region (Fig. 1). Before the CT scan was performed, the patient had an i.v. cannulation. The cannula was in his left arm pit. No central venous cannulation had been attempted. The air in the brain was in veins in the cavernous sinus and craniocervical junction. The only explanation for the identification of air in the described regions was air aspiration through the i.v. needle during cannulation. The patient was asymptomatic and left the hospital in a healthy condition. There are few reports discussing the phenomenon of air in the cavernous sinus. Nusrath et al. [3] reported a case of air in the cavernous sinus that was introduced into the brain by excessive manipulation of intravenous lines. The introduction of iatrogenic air into the cavernous sinus is more typical for cannulation in the central veins and scalp veins, which usually do not have valves [1]. Air in the cavernous sinus through peripheral venous cannulation is less typical and has been shown to happen when patients have deficient valves in their jugular venous system (internal jugular veins) [2]. In a case reported in 2008, a woman extracted her right subclavian venous line and afterwards suffered a convulsive syncope. In a cranial CT a transient air embolism in the cavernous sinus could be seen, indicating that even the extraction of venous lines can lead to air embolism in the cavernous sinuses [5]. Air embolism after extraction of a central venous line in a patient in the upright position led to a collapse and transient hemiplegia of the patient [4]. The cranial CTshowed air emboli in the cavernous sinus and the posterior wall of the foramen magnum, indicating that air embolization is not exclusively in the cavernous sinus, but also in other veins throughout the brain [4], as we also showed in the present case. In conclusion, air in the cavernous sinus could indicate infection or result from surgery or trauma [3]. In the absence of the given factors, though, air in the cavernous sinus and in the veins of the brain and craniocervical junction also could have been caused iatrogenically by manipulation of venous lines. This differential diagnosis A. K. Petridis :H. Maslehaty :A. Doukas :M. Mahvash : H. M. Mehdorn Department of Neurosurgery, University Hospital SchleswigHolstein Campus Kiel, Arnold-Heller-Str. 3, 24105, Kiel, Germany

A case of rapid-growing anaplastic meningiomas

Meningiomas are tumours originating from the leptomeningeal covering of the brain and spinal cord and are generally benign and slow growing. Rarely, they show malignant anaplastic characteristics with a high recurrence rate. A number of factors have been reported to predict this high recurrence. Such factors are histopathological ones, such as necrosis and hypercellularity, the World Health Organization (WHO) grade, mitotic index, positivity of proliferation markers (Ki-67 or MIB-1), clinical parameters such as age, gender, localisation, cytogenetic factors and radiation treatment. The present case reports a patient with a giant meningioma over the right frontal lobe who had almost all possible negative prognostic parameters and showed an explosive multifocal recurrence in a timespan of about 5 months.

Endoscopic endonasal transsphenoidal approach for resection of a coexistent pituitary macroadenoma and a tuberculum sellae meningioma

The coexistence of a pituitary macroadenoma and a tuberculum sellae meningioma is very rare. This article demonstrates the surgical technique of the simultaneous resection of a pituitary macroadenoma and a tuberculum sellae meningioma using an endoscopic, endonasal, biportal, transsphenoidal approach. A 36-year-old woman presented with frontal headache and extended visual field loss of the right eye. She underwent cranial magnetic resonance imaging (MRI) revealing a 2 × 2× 2.5 mm contrast-enhancing intrasellar and suprasellar lesion with compression of the optic chiasma. The coexistence of a pituitary macroadenoma and meningioma was suggested. A biportal endoscopic endonasal transsphenoidal approach was performed to remove both lesions. The histological results confirmed the coexistence of the pituitary macroadenoma and meningioma, World Health Organization (WHO) grade I. The endoscopic, endonasal, transsphenoidal approach is a safe and reliable minimal invasive surgical alternative for resection of the intra-, supra- and parasellar lesions, avoiding additional craniotomy.

Extensive Growth of an Anaplastic Meningioma

We present the case of a 30-year-old male patient with an almost complete destruction of the calvarial bone through an anaplastic meningioma diagnosed in line with dizziness. Neuroimaging revealed an extensive growing, contrast enhancing lesion expanding at the supra- and infratentorial convexity, infiltrating and destroying large parts of the skull, and infiltrating the skin. Due to progressive ataxia and dysarthria with proven tumor growth in the posterior fossa in the continuing course, parts of the tumor were resected. A surgical procedure with the aim of complete tumor resection in a curative manner was not possible. Six months after the first operation, due to a new tumor progression, most extensive tumor resection was performed. Due to the aggressive and destructive growth with a high rate of recurrence and tendency of metastases, anaplastic meningiomas can be termed as malignant tumors. The extrinsic growth masks the tumor until they reach a size, which makes these tumors almost unresectable. In the best case scenarios, the five-year survival is about 50%. With the presented case, we would like to show the aggressive behavior of anaplastic meningiomas in a very illustrative way. Chemotherapy, radiotherapy, and surgery reach their limits in this tumor entity.

Interaction Studies of Sialic Acids with Model Receptors Contribute to Nanomedical Therapies

Sialic acid supports nerve cell regeneration, differentiation and neuronal plasticity. Especially, polysialic acid (polySia) chains which are built up by α2,8-linked Neu5Ac Neu5Ac residues influence by their specific interactions with polySia receptors neuronal processes related to tumor spread and differentiation processes. With a combination of biophysical and biochemical methods including molecular modeling as described here it is possible to support cell biological experiments and in vivo studies on a nanoscale level. The submolecular analytical approaches which are directed to crucial functional groups focus on the potential therapeutic impact of sialic acids and in particular polySia. Such results are helpful for the development of new drugs which might have a high clinical relevance in respect to the therapy of various diseases correlated to neuronal regeneration, tumor spread and infections. It is not surprising that several diseases belonging to these different clinical fields (e.g. oncology, infection diseases, neuronal disorder) can be treated as indicated because sialic acids represent essential contact structures on numerous cell surfaces in dependence to their state of differentiation.

Post-traumatic extensive knee ganglion cyst

A rare case of a posttraumatic extensive ganglion cyst of the anterolateral thigh with connection to the knee joint is presented. A 54-year-old man presented a palpable mass in the anterolateral region of his right thigh with a 15 months existing sense of fullness and tightness. He had an accident with his bicycle 21 months ago. Magnetic resonance imaging (MRI) was performed showing a cyst inside the quadriceps femoris muscle between vastus lateralis and intermedius with connection to recessus suprapatellaris and knee joint. In addition MRI detected a traumatic lesion in the quadriceps femoris tendon in the near of the knee joint. The ganglion cyst was 18 cm long and was excised completely. Intraoperatively, the knee joint connection was confirmed and excised as well. The ganglion cyst was filled with a gelatinous and viscous fluid.