Embolization of the Middle meningeal artery in chronic subdural hematoma - A systematic review.

Chronic subdural hematomas (cSDH) are one of the most frequent reasons for consultation in neurosurgery. Multiple authors have proposed middle meningeal artery embolization (MMAE) as an option in cSDH patients to manage recurrence or avoid surgery altogether. Although many articles have been published on the matter, the current body of evidence still has to be evaluated before MMAE is integrated into clinical practice. The goal of this study was to review the evidence on MMAE in cSDH to assess its safety, feasibility, indications and efficacy. We performed a systematic review of the literature according to PRISMA guidelines using multiple electronic databases. Our search yielded a total of 18 original articles from which data were extracted. A total of 190 patients underwent MMAE from which 81.3% were symptomatic cSDH. Over half (52.3%) of the described population were undergoing antithrombotic therapy. Most (83%) procedures used polyvinyl alcohol (PVA) particles and no complications were reported regarding the embolization procedures. Although the definition of resolution varied among authors, cSDH resolution was reported in 96.8% of cases. MMAE is a feasible technique for cSDH, but the current body of evidence does not yet support its use as a standard treatment. Further studies with a higher level of evidence are necessary before MMAE can be formally recommended.

Chronic Subdural Hematoma: Toward a New Management Paradigm for an Increasingly Complex Population.

Chronic subdural hematoma (cSDH) is a frequent yet poorly studied entity. Patients with cSDH are increasingly using antithrombotic medication, are now older, and present with a variety of clinical symptoms, including incidental discoveries. Despite this increasing complexity, management has remained roughly unchanged since the late 1990s. We review here the state of cSDH research under way at Université de Sherbrooke and around the world with a focus on studies addressing specific gaps in the current evidence base. We show that evidence is lacking at many decision points in the typical cSDH patient treatment algorithm. No definition of cSDH is universally accepted, and a formal definition project, along with suggested common data elements to be reported in future trials (CODE-CSDH: formal cSDH definition project) is ongoing. An amendment to International Statistical Classification of Diseases and Related Health Problems (ICD-11) has also been proposed to improve classification and registry research. Within the cSDH clinical assessment, evidence for the occurrence of nonepileptic, stereotypical, and intermittent symptoms (NESIS) is emerging. The GENESIS study (Generation Evidence on the etiology and management of NESIS) will test etiological and therapeutic hypotheses for this patient subpopulation. For patients at high risk of recurrence, the TRACS (TXA for cSDH) and EMMACS studies (Embolization of the Middle Meningeal Artery in Chronic Subdural Hematoma study) are, respectively, assessing the use of tranexamic acid and meningeal artery embolization. The overarching vision is that patients with cSDH might be stratified for operative versus conservative treatment based on the need for mass effect removal, then be offered adjuvant therapies based on their risk of recurrence and thrombotic complications. We believe that such tailoring of therapy to each individual should help improve outcomes.

The wire anchor loop traction (WALT) maneuver.

Crossing the neck of large complex intracranial aneurysms for the purposes of stent deployment can be challenging using standard over the wire techniques. We describe a novel yet simple technique for straightening out the loop formed within a large intracranial aneurysm, which is often required in order to cross the aneurysm neck into the distal branch. Both the microcatheter and microwire are initially introduced into the distal vasculature, followed by withdrawal of the microwire to a point parallel to the distal exiting branch. The microcatheter and microwire are then gently withdrawn and a series of maneuvers to gradually reduce the loop is performed, obviating the need for distal purchase in the form of a stent, balloon, or coil, which have previously been described to maintain distal purchase.

Anastomosis Between the Ascending Pharyngeal Artery and the Posterior Inferior Cerebellar Artery Through the Jugular Foramen: A Cadaveric Observation.

BACKGROUND: The ascending pharyngeal artery (APA) may, in very rare cases, supply the posterior inferior cerebellar artery (PICA). In reported cases, when such is the case, the ipsilateral vertebral artery (VA) does not supply the PICA, and most of the time it is hypoplastic. OBJECTIVE: To describe a unique cadaveric observation of a direct anastomosis between the posterior division (neuromeningeal) of the jugular branch of the APA and the PICA, where the PICA is also supplied by a normal-size VA. METHODS: A direct connection between the APA and the PICA was examined in a cadaveric specimen using a 3-dimensional endoscope and a surgical microscope. RESULTS: The enlarged jugular branch of the posterior division of the APA entered intracranially via the jugular foramen in its pars vascularis. It then connected directly with the lateral medullary segment of the PICA. The first segment of the PICA originated from a left vertebral artery of normal size and continued its normal course beyond the junction with the jugular branch of the APA. CONCLUSION: Both the VA and the jugular branch of the APA may simultaneously supply the PICA territory. Recognition of this anatomic variant is relevant when planning surgical or endovascular treatments.

Spreading of multiple Listeria monocytogenes abscesses via central nervous system fiber tracts: case report.

Animal studies have shown that Listeria monocytogenes can probably access the brain through a peripheral intraneural route, and it has been suggested that a similar process may occur in humans. However, thus far, its spreading through the central nervous system (CNS) has not been completely elucidated. The authors present a case of multiple L. monocytogenes cerebral abscesses characterized by a pattern of distribution that suggested spread along white matter fiber tracts and reviewed the literature to identify other cases for analysis. They elected to include only those cases with 3 or more cerebral abscesses to make sure that the distribution was not random, but rather followed a pattern. In addition, they included those cases with abscesses in both the brainstem and the cerebral hemispheres, but excluded cases in which abscesses were located solely in the brainstem. Of 77 cases of L. monocytogenes CNS abscesses found in the literature, 17 involved multiple abscesses. Of those, 6 were excluded for lack of imaging and 3 because they involved only the brainstem. Of the 8 remaining cases from the literature, one was a case of bilateral abscesses that did not follow a fiber tract; another was also bilateral, but with lesions appearing to follow fiber tracts on one side; and in the remaining 6, to which the authors added their own case for a total of 7, all the abscesses were located exclusively in the same hemisphere and distributed along white matter fiber tracts. The findings suggest that after entering the CNS, L. monocytogenes travels within the axons, resulting in a characteristic pattern of distribution of multiple abscesses along the white matter fiber tracts in the brain. This report is the first description suggesting intraaxonal CNS spread of L. monocytogenes infection in humans following its entry into the brain. This distinct pattern is clearly seen on imaging and its recognition may be valuable in the diagnosis of listeriosis. This finding may allow for earlier diagnosis, which may improve outcome.

The wire anchor loop traction (WALT) maneuver.

Crossing the neck of large complex intracranial aneurysms for the purposes of stent deployment can be challenging using standard over the wire techniques. We describe a novel yet simple technique for straightening out the loop formed within a large intracranial aneurysm, which is often required in order to cross the aneurysm neck into the distal branch. Both the microcatheter and microwire are initially introduced into the distal vasculature, followed by withdrawal of the microwire to a point parallel to the distal exiting branch. The microcatheter and microwire are then gently withdrawn and a series of maneuvers to gradually reduce the loop is performed, obviating the need for distal purchase in the form of a stent, balloon, or coil, which have previously been described to maintain distal purchase.

Aneurysmal subarachnoid haemorrhage from a neuroimaging perspective.

Neuroimaging is a key element in the management of patients suffering from subarachnoid haemorrhage (SAH). In this article, we review the current literature to provide a summary of the existing neuroimaging methods available in clinical practice. Noncontrast computed tomography is highly sensitive in detecting subarachnoid blood, especially within 6 hours of haemorrhage. However, lumbar puncture should follow a negative noncontrast computed tomography scan in patients with symptoms suspicious of SAH. Computed tomography angiography is slowly replacing digital subtraction angiography as the first-line technique for the diagnosis and treatment planning of cerebral aneurysms, but digital subtraction angiography is still required in patients with diffuse SAH and negative initial computed tomography angiography. Delayed cerebral ischaemia is a common and serious complication after SAH. The modern concept of delayed cerebral ischaemia monitoring is shifting from modalities that measure vessel diameter to techniques focusing on brain perfusion. Lastly, evolving modalities applied to assess cerebral physiological, functional and cognitive sequelae after SAH, such as functional magnetic resonance imaging or positron emission tomography, are discussed. These new techniques may have the advantage over structural modalities due to their ability to assess brain physiology and function in real time. However, their use remains mainly experimental and the literature supporting their practice is still scarce.

Comparative study of Gamma Knife surgery and percutaneous retrogasserian glycerol rhizotomy for trigeminal neuralgia in patients with multiple sclerosis.

OBJECT: Among patients with multiple sclerosis (MS) there is a high incidence of trigeminal neuralgia (TN), and outcomes after treatment seem inferior to those in patients suffering from idiopathic TN. The goal of this study was to evaluate clinical outcomes in patients with MS-related TN after Gamma Knife surgery (GKS) and compare them with those obtained using percutaneous retrogasserian glycerol rhizotomy (PRGR). METHODS: The authors retrospectively reviewed the charts of 45 patients with MS-related TN. The first procedure undertaken was GKS in 27 patients and PRGR in 18 patients. Pain had been present for a median of 60 months (range 12-276 months) in patients who underwent GKS and 48 months (range 12-240 months) in patients who underwent PRGR. The following outcome measures were assessed in both groups of patients: pain relief (using the Barrow Neurological Institute [BNI] Pain Scale), procedure-related morbidity, time to pain relief and recurrence, and subsequent procedures that were performed. RESULTS: The median duration of follow-up was 39 months (range 13-69 months) in the GKS group and 38 months (range 2-75 months) in the PRGR group. Reasonable pain control (BNI Pain Scale Scores I-IIIb) was noted in 22 patients (81.5%) who underwent GKS and in 18 patients (100%) who underwent PRGR. For patients who underwent GKS, the median time to pain relief was 6 months; for those who underwent PRGR, pain relief was immediate. In the GKS group 12 patients required subsequent procedures (3 patients for absence of response and 9 patients for pain recurrence), whereas in the PRGR group 6 patients required subsequent procedures (all for pain recurrence). As of the last follow-up, complete or reasonable pain control was finally achieved in 23 patients (85.2%) in the GKS group and in 16 patients (88.9%) in the PRGR group. The morbidity rate was 22.2% in the GKS group (all due to sensory loss and paresthesia) and 66.7% in the PRGR group (mostly hypalgesia, with 2 patients having corneal reflex loss and 1 patient suffering from meningitis). CONCLUSIONS: Both GKS and PRGR are satisfactory strategies for treating MS-related TN. Gamma Knife surgery has a lower rate of sensory and overall morbidity than PRGR, but requires a delay before pain relief occurs. The authors propose that patients with extreme pain in need of fast relief should undergo PRGR. For other patients, both management strategies can lead to satisfactory pain relief, and the choice should be made based on patient preference and expectations.

SUNCT syndrome successfully treated by gamma knife radiosurgery: case report.

BACKGROUND: The SUNCT syndrome (short-unilateral neuralgiform headache with conjunctival injection and tearing) can be very disabling for affected patients and is often refractory to medical management. We report the first case of SUNCT with a successful response to stereotactic radiosurgery without any adverse effect. CASE: After failing optimal medical treatment, a 82-year old male patient suffering from SUNCT syndrome was treated with Gamma knife radiosurgery. The trigeminal nerve and sphenopalatine ganglion were targeted with a maximum dose of 80 Gy each. The patient had complete pain cessation 2 weeks after the treatment, and remains pain-free with no medication at the latest follow-up 39 months after radiosurgery. He did not have any side effect from the procedure. CONCLUSION: Gamma knife radiosurgery is an option for medically refractory SUNCT patients.