Liponeurocytoma is a rare benign tumor of the central nervous system, which develops mainly in adult patients within the posterior fossa. The WHO has categorized this entity in their last classification of 2016 as a benign grade II tumor. Histopathological characteristics contain neuronal and variable astrocytic differentiation with foci of lipomatous distinction. Up to now only a few case reports and case series are published and the knowledge of this tumor is still very limited. General treatment guidelines do not exist. Aim of this study was to analyze the literature to create treatment guidelines. PRISMA (i.e., Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were followed to query existing online databases between January 1, 1978 and May 15, 2018. Systematic review of the literature revealed 73 cases (40 female, 33 male) of a liponeurocytoma whereof 59 cases (80.8%) occurred in the posterior fossa. Ki-67/MIB-1 proliferation index was described in 58 cases showing a mean value of 3.73% ± 4.01. Follow-up was performed in 49 cases with a median length of 52.02 ± 50.52 months, showing tumor recurrence in 14 cases (28.57%). Tumor recurrence was observed in only one case (1/12, 8.33%) after adjuvant radiotherapy, while tumor recurrence was seen in 13/29 patients (44.83%), who did not receive adjuvant radiotherapy. Liponeurocytomas are rare benign tumors, occurring mainly in the cerebellum. Therapy of choice is surgery. Postoperative radiotherapy seems to lower the risk of tumor recurrence and should be offered to the patient.
The purpose of this article is to focus for the first time on the operative management of a direct vertebral artery (VA)-posterior inferior cerebellar artery (PICA) end-to-end anastomosis in a partially thrombosed giant VA-PICA-complex aneurysm and to underline its usefulness as an additional treatment option. The operative technique of a direct VA-PICA end-to-end anatomosis is described in detail. The VA was entering the large aneurysm sack. Distally, the PICA originated from the aneurysm sack-VA-complex. The donor and recipient vessel were cut close to the aneurysm. Whereas the VA was cut in a straight manner, the PICA was cut at an oblique 45-degree angle to enlarge the vascular end diameter. Vessel ends were flushed with heparinized saline and sutured. The thrombotic material inside the aneurysm sack was removed and the distal VA clipped, leaving the anterior spinal artery and brainstem perforators free. The patient regained consciousness without additional morbidity. Magnetic resonance imaging scans revealed a completely decompressed brainstem without infarction. The postoperative angiograms demonstrated a good filling of the anastomosed PICA. Despite the caliber mistmatch of these two vessels the direct VA-PICA end-to-end anastomosis provides an accurate alternative in addition to other anastomoses and bypass techniques, when donor and recipient vessels are suitable and medullary perforators do not have to be disrupted.
High-resolution magnetic resonance imaging (HR-MRI) using three-dimensional fast imaging employing steady-state acquisition (3D-FIESTA) and double-dose contrast-enhanced three-dimensional fast spoiled gradient echo (3D-FSPGR) sequences is considered to be a useful tool in detecting neurovascular compression in patients with trigeminal neuralgia. The purpose of this study was to analyze the accuracy and preoperative diagnostic value of these high-resolution imaging techniques in patients with trigeminal neuralgia, in a single-blind study. The preoperative MRI images of 21 consecutive patients were matched to one neuroradiologist, who was blind as to which side exhibited the symptoms. The images and post-processing multiplanar reconstructions were compared with the video-documented operative observations. HR-MRI using only 3D-FSPGR sequences demonstrated neurovascular compression in accordance with the intraoperative finding in 11 patients (52.4%). In the subgroup where, additionally, 3D-FIESTA sequences were available, neurovascular compression was in accordance with the intraoperative finding in 71.4% (n = 7). High-resolution magnetic resonance imaging using double-dose contrast-enhanced 3D-FSPGR and 3D-FIESTA sequences is currently not sufficient enough to make an accurate prediction of neurovascular compression in a single-blind setting. These 3D imaging techniques currently provide only limited information, and one should consider their use carefully when identifying patients with trigeminal neuralgia from operation until image quality is improved by superior image resolution that can accurately discriminate vessels surrounding the trigeminal root entry zone.
Encephalomeningocele is a herniation of the brain and meninges through a congenital bone defect resulting from the failure of normal midline fusion of the cranial neural tube. Various sites are possible; however, among Caucasians more than 70% of encephaloceles are located on the occipital/posterior part of the cranium. Usually they contain degenerative cerebral cortex, which is often excised during surgical closure of the defect. Techniques to preserve the herniated brain tissue have been described, but they focus on increasing the intracranial cavity by ventriculomegaly and retracting the encephalocele into new intracranial space in a second stage, as a result of hydrocephalic treatment. The authors report a well-documented newborn with a large encephalocystocele of the left occipital lobe. This encephalocele included the left lateral ventricle and a part of the cerebellum, and was covered with allopathic skin. Initially the cystic portion was removed so that a partial reduction of the encephalocystocele was achieved. Six months later, the surgical closure of the defect was performed, with preservation of the occipital and cerebellar parenchyma, by incising the tentorium and retracting the cortex to the newly created infratentorial space. The bony defect was covered with autologous osseous graft harvested from parietal bone and reconstructed. In the long-term follow-up after 13 years, the child has preserved visual function.
The authors review the pertinent literature dealing with all aspects of cerebral cavernous malformations in the adult. Clinical, neuroradiological, pathological, and epidemiological aspects are presented. The clinical significance of bleeding from cavernous malformations and various hemorrhage patterns are discussed in relation to the factors that influence hemorrhage rates. Recent reports describing the genetic mechanisms of inheritance, de novo formation, and angiogenesis of cavernomas are reviewed as well. Brainstem cavernomas have received special attention, since their clinical management is controversial in the literature. Presently, microsurgical removal is favored by the majority of authors and stereotactic radiosurgery appears to be inappropriate for prevention of bleeding from a cavernoma. Our own case material consists of data of 72 patients operated upon during the past 5 years. Twenty-four patients harbored the lesion within the brainstem, 18 within the deep white matter of the hemispheres, 12 in the basal ganglia or thalamus, 11 in superficial areas of the hemisphere, and seven within the cerebellum. The perioperative morbidity rate was 29.2% (21/72) while the rate of long-term morbidity was 5.5% (4/72), with no mortality in this series. It is concluded that cerebral cavernous malformations, including lesions in critical regions of the brain, can be treated microsurgically with excellent results and an acceptable morbidity.
Associated aneurysms (AAs) are presumed to represent an additional risk factor for intracranial haemorrhage from cerebral arterio-venous malformations (AVMs). To date, efforts to capture their natural history, as well as to identify aneurysms with the potential capability of regression after AVM treatment remain incomprehensive. As the aneurysm size represents an important aspect for the treatment indication of incidental saccular aneurysms, this factor has rarely been encountered for the treatment of AAs so far. The present study aims to determine the angiographic and clinical characteristics of AAs with special focus on aneurysm size and their consequences for treatment. Patients with cerebral AVMs, treated in our department between 1990 and 2013, were analyzed retrospectively. Only patients with supratentorial AVMs and flow-related AAs of the feeding arteries were evaluated. Thus, patients harboring AVMs of the cerebellum and the brain stem and patients with intranidal, venous or remote aneurysms were excluded. Treatment strategies were assessed with special attention on bleeding source and on AA size. In 59 of 409 patients (14%) with supratentorial AVMs, a total of 85 AAs of the feeding arteries were identified. 14 of 59 individuals (24%) presented with multiple AAs. Of 85 AA, 58 aneurysms (68%) were classified as proximal and 27 aneurysms (32%) as distal. The most common location of AAs was the middle cerebral artery (MCA, 39%), followed by the internal carotid artery (ICA, 27%) and the anterior cerebral artery (ACA, 21%). The mean AA size was 4.4 mm ± 3.4 mm. Intracranial haemorrhage was found in 21 of 59 patients (36%) with coexisting AAs. Among these, 10 individuals (17%) suffered from rupture of an AA, accounting for nearly half of all bleedings in this subgroup. Among those patients bearing a single AA, the size of ruptured aneurysms differed significantly from those unruptured (6.6 mm vs. 4.4 mm, p = 0.0046). Nineteen patients (32%) received treatment of 22 AAs, whereas sole AVM treatment was adopted in 26 patients (44%) and conservative management in 14 patients (24%). The main reasons to leave AAs untreated were the small AA size (<5 mm), poor clinical state or treatment denial by the patients. The aneurysm size of AAs in AVM influences the risk of haemorrhage. Therefore, the treatment of larger (diameter ≥5 mm) AAs should be considered, even if a treatment indication of the associated AVM is not given.
The present study aimed to determine the clinical presentation, the multimodal interdisciplinary treatment strategies and outcome of posterior fossa arterio-venous malformations (AVMs) in our neurovascular centre. Fifty-three patients with a posterior fossa AVM were seen between 1998 and 2012 and analysed retrospectively. Patients were either managed conservatively or treated with endovascular, microsurgical or radiosurgical procedures or in combination. Thirty-nine patients (74 %) presented with intracranial haemorrhage and 14 patients (26 %) with unspecific symptoms. In 22 cases with haemorrhage (56 %), an intracerebellar haematoma was found, whereas 17 patients (44 %) suffered from subarachnoid haemorrhage. AVMs were located in the cerebellum in 44 patients (83 %), in the brainstem in four patients (7.5 %) and the cerebello-pontine angle in another four individuals (7.5 %). Forty-two patients (79 %) were treated either by emboliziation (n = 12, 29 %), surgical resection (n = 16, 38 %), surgical resection with preoperative embolization (n = 12, 29 %) or radiotherapy alone (n = 2, 4 %). A total of eleven patients did not receive any treatment (21 %). Both, morbidity and mortality related to treatment were 12 %, whereas overall morbidity and mortality was 26 and 15 %, respectively. Complete AVM elimination was achieved in 81 % of the treated lesions. A multimodal treatment sequence nowadays represents the gold standard for posterior fossa AVMs. Patients are at high risk for morbidity and mortality, due to the impact of haemorrhage and treatment. Therefore, treatment has to be thoroughly indicated, especially for those patients without bleeding. The initial neurological condition seems to be crucial in terms of clinical outcome.
Cerebellar liponeurocytoma is a rare tumor of the central nervous system occurring mainly in the posterior fossa, which shows neuronal and variable astrocytic differentiation with foci of lipomatous differentiation. Liponeurocytoma develops in adult patients and is defined in the World Health Organization classification of 2016 as a rare benign grade II tumor. A 39-year-old Italian man presented to our department suffering from headache and nausea. Magnetic resonance imaging revealed a right-sided cerebellar lesion showing poor contrast enhancement without an obstructive hydrocephalus. Surgery was indicated and total tumor resection was achieved. He was discharged without any neurological deficits. Histopathological examinations revealed a cerebellar liponeurocytoma. A neurological follow-up examination revealed no neurological deficit directly after surgery and 1 year later. Radiotherapy was recommended at the neurooncological board despite the total removal of the tumor, but our patient refused adjuvant radiotherapy. Magnetic resonance imaging of his neurocranium with and without contrast enhancement 48 hours after surgery and 15 months after surgery showed no residual tumor. Liponeurocytomas are rare benign tumors occurring in the majority of cases in the cerebellum. The therapy of choice is surgery. Postoperative radiotherapy has to be discussed individually, but seems to be sufficient if complete tumor resection is not achieved or in cases of a tumor recurrence.