Pascal J. Mosimann

The pressure cooker technique for the treatment of brain AVMs.

Arteriovenous malformations (AVMs) may be cured by injecting liquid embolic agents such as Onyx. Reflux, however, can sometimes be difficult to control and may jeopardize a complete embolization. The pressure cooker technique (PCT) was designed to create an anti-reflux plug by trapping the detachable part of an Onyx-compatible microcatheter with coils and glue in order to obtain wedge-flow conditions, thereby enabling a better understanding of macrofistulous AVMs and a more comprehensive, forceful and controlled Onyx embolization. The PCT might enlarge the range of AVMs amenable to endovascular cure. Three illustrative cases are presented.

Stent Retriever Use for Retrieval of Displaced Microcoils: A Consecutive Case Series

SUMMARY: Coil displacement during endovascular coiling procedures may require coil retrieval in the context of flow limitation or thromboembolic risk. No standard recommended method of coil retrieval exists. We present a consecutive series of 14 patients with displaced coil during aneurysm coiling in whom the complication was effectively managed with the use of a stent retriever system. Two illustrative cases from the 14 are described, and technical notes are detailed regarding use of the technique. The use of stent retrievers presents a simple, safe, and effective choice for removal of prolapsed coils during aneurysm coiling.

Pulsatile tinnitus caused by an aneurysm of the transverse-sigmoid sinus: a new case report and review of literature.

A 28-year-old woman consulted for disabling pulsatile tinnitus. Clinical examination suggested a venous etiology. An aneurysm of the transverse-sigmoid sinus was identified on computed tomography angiography (CTA) and confirmed by digital subtraction angiography. Endovascular occlusion of the aneurysm with detachable coils permanently eliminated the bruit. Thus, this report is of a new case of pulsatile tinnitus caused by an aneurysm of the transverse-sigmoid sinus, with a focus on a literature review and etiopathophysiology. Embryological studies suggest that these aneurysms represent a partial remnant of the petrosquamous sinus.

Rupture of a concealed aneurysm after intravenous thrombolysis of a thrombus in the parent middle cerebral artery.

BACKGROUNDnManagement of ischemic stroke in the presence of aneurysmal brain disease is controversial. Recent retrospective evidence suggests that in selected patients, intravenous thrombolysis (IVT) remains a safe approach for reperfusion.nnnMETHODSnWe document a case of post-thrombolysis aneurysmal rupture. Supported by additional scientific literature we postulate that acute aneurysmal thrombosis leading to stroke in the culprit artery may be an ominous sign of rupture and should be considered separately from fortuitously discovered distant aneurysmal disease.nnnRESULTSnA 71-year-old female presented with an acute right middle cerebral artery stroke syndrome. IVT allowed vessel reperfusion and revealed a previously concealed, juxtaposed non-giant M1 segment saccular aneurysm. Secondary aneurysmal rupture ensued. The aneurysm was secured by surgical clipping. Postoperative course was uneventful.nnnCONCLUSIONSnThis case shows that despite reports of thrombolysis safety in the presence of brain aneurysms, thrombolysis remains potentially hazardous and hints toward an increased risk when the stroke arises on the parent vessel itself.

Diaphragm of the internal carotid artery: a novel cause of pulsatile tinnitus

Pulsatile tinnitus (PT) may result from many different vascular and non-vascular causes [1], some of which were only recently discovered [2]. The psychological impact of PT may be so severe that it may lead to depression or even suicide [3]. Identifying a treatable cause is essential. Despite complete clinical and imaging investigations, including conventional digital subtracted angiography (DSA), PT often remains cryptogenic, meaning that other etiologies are still currently unknown [4]. We report diaphragm of the internal carotid artery (ICA) as a novel cause of PT in two patients. Two 64 and 58-year-old women with unilateral PT were referred to our institution in 2008 and 2011. PT had been present for 10 and 12 months, respectively. The degree of disability was assessed using the visual or verbal analogue scale (VAS) from 0 to 10 and by evaluating the quality of sleep, as well as the presence of depressive symptoms. The first patient estimated her disability to be as high as 8/10 on the VAS, while the second estimated it to be 9/10. Both needed regular nighttime sedation and complained of physical and moral fatigue. Otoscopic examination was normal. No PT was objectively perceived during auscultation of the head. The bruit was interrupted by ipsilateral common carotid artery compression. Cerebral MR and CT, including arterial and venous explorations, were within normal limits. A translucent endoluminal web-like diaphragm of the upper cervical ICA was identified on conventional DSA (Figs. 1, 2). To verify whether the diaphragm was responsible for the tinnitus, a balloon test occlusion (BTO) was performed. Patients were informed that a balloon would be placed and inflated at random times in their ICA below the diaphragm without their feeling or noticing it. They were instructed to inform the neuroradiologist every time the bruit disappeared. Two consecutive BTOs at the level of the diaphragm interrupted the PT. Due to the severe functional impact of PT, stenting of the ICA diaphragm was proposed. ICA stenting was performed under optimal anti-aggregation and full heparinization. A 5 9 30-mm Carotid Wall Stent (Boston Scientific Inc.) was deployed over the stenotic diaphragm. Stenting of the diaphragm led to the disappearance of PT without complication. No recurrent bruit was reported during the follow-up at 12 and 36 months, respectively. The initial description of a diaphragm dates back to 1967. [5] It may be defined as a translucent endoluminal web perpendicular to the arterial wall that should not change or disappear after modification of the patient’s head position. The unsuspecting eye may easily confuse diaphragms with arterial kinks, meaning that they may be more prevalent than we currently believe. ICA diaphragms have already been recognized as a rare but true cause of ischemic stroke [5, 6]. To the best of our knowledge, they have not previously been recognized as a cause of PT. From a physiopathological standpoint, upper cervical diaphragms may possibly induce turbulent blood flow close to the cochlea that may be perceived as a sound synchronous to the cardiac pulse. In our two patients, it was not possible to diagnose the presence of the diaphragm without a conventional angiogram. Conventional DSA is always performed in our center for patients suffering from disabling PT when conventional S. Lenck (&) M.-A. Labeyrie P. J. Mosimann J.-P. Saint-Maurice E. Houdart Department of Neuroradiology, Hôpital Lariboisière, 2, rue Ambroise Paré, 75010 Paris, France e-mail: stephanie.lenck@orange.fr

Jaw Immobilization for Gamma Knife Surgery in Patients with Mandibular Lesions: A Newly, Innovative Approach

Background: The purpose of our report is to describe an innovative system used for mandibular immobilization during Gamma Knife surgery (GKS) procedures. It is based on an approach originally developed in Marseille in extracranial lesions, close to or involving the mandible, which may imply a certain degree of movement during the therapeutic image acquisitions and/or GKS treatment. Methods: The maxillofacial surgeon applied bone titanium self-tapping monocortical screws (4; 2 mm diameter, 10 mm length) between roots of the teeth in the fixed gingiva (upper and lower maxillae) the day before GKS (local anesthesia, 5-10 min time). Two rubber bands were sufficient for the desired tension required to undergo GKS. We further proceeded with application of the Leksell stereotactic G frame and carried out the usual GKS procedure. Results: The mean follow-up period was 2.3 years (range 0.6-3). Three patients have been treated with this approach: 2 cases with extracranial trigeminal schwannomas involving the mandibular branch, with decrease in tumor size on MR follow-up; 1 case with residual paracondylian mandibular arteriovenous malformation following partial embolization, completely obliterated at 7 months (digital subtraction angiography programmed 1 year after treatment). Conclusions: Jaw immobilization appears to be a quick, minimally invasive, safe and accurate adjunctive technique to enhance GKS targeting precision.

Distal cerebral protection device filled with calcified plaque debris after carotid stenting.

A 65-year-old patient with a history of smoking, hypercholesterolemia, and coronary stenting after myocardial infarction was referred for carotid stenting due to recurrent episodes of transient aphasia and right-sided weakness, despite best medical therapy—including aspirin and statins. Magnetic

A new endovascular technique for small anterior choroidal artery aneurysms. A consecutive series using the 3-catheter-protective technique.

INTRODUCTIONnEndovascular treatment of small anterior choroidal artery (AChA) aneurysms can be challenging, especially if the AChA arises from the sac. Preserving its patency during embolization is as important as obliterating the aneurysm. We describe a variant of the protective microcatheter technique (PMT) in a series of six patients with AChA aneurysms where the AChA emerged from the sac.nnnMETHODSnThree different microcatheters (KT) were used. The first microcatheter was placed in the AChA to protect it. A remodeling balloon-catheter was then positioned in the internal carotid artery to stabilize the coils during embolization and to control a potential rupture. The third microcatheter was finally used to coil the aneurysm.nnnRESULTSnMean sac size of anterior choroidal artery aneurysms was 2×2×2mm. All aneurysms were successfully occluded. There was neither ischemic complication nor ruptured aneurysm during endovascular treatment. A final angiogram demonstrated AChA patency in all cases.nnnCONCLUSIONnThe 3KT-PMT for AChA aneurysms appears to be safe and effective to prevent AChA occlusion during aneurysm coiling, especially when the AChA arises from the sac.

Usefulness of intra-articular bupivacain and lidocain adjunction in MR or CT arthrography: A prospective study in 148 patients

PURPOSEnTo evaluate the influence of shorter- and longer-acting intra-articular anaesthetics on post-arthrographic pain.nnnMATERIALS AND METHODSn154 consecutive patients investigated by MR or CT arthrographies were randomly assigned to one of the following groups: 1--intra-articular contrast injection only; 2--lidocain 1% adjunction; or 3--bupivacain 0.25% adjunction. Pain was assessed before injection, at 15 min, 4 h, 1 day and 1 week after injection by visual analogue scale (VAS).nnnRESULTSnAt 15 min, early mean pain score increased by 0.96, 0.24 and 0 in groups 1, 2 and 3, respectively. Differences between groups 1 & 3 and 1 & 2 were statistically significant (p=0.003 and 0.03, respectively), but not between groups 2 & 3 (p=0.54). Delayed mean pain score increase was maximal at 4 h, reaching 1.60, 1.22 and 0.29 in groups 1, 2 and 3, respectively. Differences between groups 1 & 2 and 2 & 3 were statistically significant (p=0.002 and 0.02, respectively), but not between groups 1 & 2 (p=0.46). At 24 h and 1 week, the interaction of local anaesthetics with increase in pain score was no longer significant. Results were independent of age, gender and baseline VAS.nnnCONCLUSIONnIntra-articular anaesthesia may significantly reduce post-arthrographic pain. Bupivacain seems to be more effective than lidocain to reduce both early and delayed pain.

Anterior inferior cerebellar artery aneurysms mimicking vestibular schwannomas.

Unruptured anterior inferior cerebellar artery (AICA) aneurysms are rare but potentially lethal cerebellopontine angle (CPA) lesions that may be misdiagnosed as vestibular schwannomas when they present with vestibulo‐cochlear symptoms.