Spinal cord arterio-venous shunts: From classification to therapeutic management.

Spinal Cord Arterio-Venous shunts (SCAVSs) are a rare disease. The aim of this paper is to describe how we classify and consider management of SCAVSs in relation to the location of the shunt focusing mainly on intradural SCAVSs. The anatomical features of the SCAVSs together with data provided by MRI and CT scans allow identification of four types of SCAVSs: paraspinal, epidural, dural and intradural ones. Clinical and neuroradiologic characteristics are described for each entity as well as the therapeutic endovascular management at our institution between 2002 and 2020. The therapeutic management of SCAVSs, and in particular of intradural shunts, remains mainly based on endovascular treatment as a first-choice approach. Understanding properly the lesional and regional vascular anatomy is mandatory to plan an appropriate therapeutic strategy and obtain good clinical results stable at long term follow up.

A unique case of pure lateral spinal cord herniation.

BACKGROUND: Spinal cord herniation (SCH) remains a challenging diagnosis for neuroradiologists and may require treatment challenging for neurosurgeons. Most cord herniations are usually found at anterior thoracic levels. CLINICAL PRESENTATION: A 28-year-old woman presented at our department with a 7-year history of progressive myelopathy. MR analysis showed a displacement of the spinal cord in a lateral thoracic dural defect. The herniated cord was released using a microscope and the patient significantly recovered 6 months after surgery. CONCLUSION: We present a unique case of pure lateral SCH. In the light of reviewed literature and operative findings, the underlying pathophysiological mechanisms are discussed.

[Therapeutic and endovascular management of cerebral mycotic aneurysms]. / Traitement interventionnel des anévrismes mycotiques cérébraux.

Infective endocardites are associated with both ischemic and hemorrhagic neurological complications and also with cerebral abscesses and the development of "mycotic" aneurysms, which are detected in about 5 % of patients in the acute and sub-acute phase of the infection. Data about their natural history and their hemorrhagic risk are scarce and fragmented. The therapeutic management is represented by the medical treatment of the infection with interventional abstention, the surgical treatment and the endovascular approach by selective embolization of the aneurysm. No evidence is provided concerning the superiority of a specific approach. Mycotic aneurysms remain a diagnostic and therapeutic challenge and their management is necessarily based on a multidiscplinary approach.

Advice and hints on imaging the lateral sellar compartments.

The lateral sellar compartment is a complex anatomical structure containing many different elements, any of which can be at the root of a pathological condition. MRI is the examination of choice for this region, and requires the use of specific protocols and systematic examination of each of these elements to produce a suitable diagnosis.

Follow-up of coiled intracranial aneurysms: comparison of 3D time-of-flight MR angiography at 3T and 1.5T in a large prospective series.

BACKGROUND AND PURPOSE: Our aim was to compare 3D TOF-MRA sequences at 3T and 1.5T in the follow-up of coiled aneurysms. The follow-up of coiled intracranial aneurysms is mandatory to depict potential recanalization. 3D-TOF MRA is an appropriate tool for this purpose. MATERIALS AND METHODS: DSA and 3D TOF-MRA at 1.5T and 3T were performed in a prospective series of 126 aneurysms in 96 patients (58 women, 38 men; age, 25-75 years; mean, 51.3 ± 11.3 years). DSA was the reference standard to which the accuracy of 3D TOF-MRA was compared. The quality of aneurysm occlusion was assessed independently and anonymously by a core lab by using a 3-grade scale (total occlusion, neck remnant, and aneurysm remnant). Adequate occlusion was defined as total occlusion or neck remnant and used in a 2-grade scale: adequate occlusion/aneurysm remnant. RESULTS: With DSA, total occlusion was depicted in 58 aneurysms (46.0%); neck remnant, in 33 aneurysms (26.2%); and aneurysm remnant, in 35 aneurysms (27.8%). Adequate occlusion was seen in 91 cases (72.2%). A remnant (aneurysm or neck) was depicted in 68 cases (54.0%). For the 3 imaging techniques and regardless of scale used, the interobserver agreement was always greater at 3T than at 1.5T. SE and NPV for the prediction of aneurysm remnant versus adequate occlusion were higher at 3T than at 1.5T (SE 3T, 0.74; SE 1.5T, 0.54; NPV 3T, 0.90; NPV 1.5T, 0.85). CONCLUSIONS: In this large prospective series of patients, 3D TOF-MRA was superior at 3T to 1.5T for the evaluation of coiled intracranial aneurysms.

[Sphenoid bone: surgical techniques]. / Les voies d'abord du sphénoïde.

Many operative approaches to the sphenoid are possible. This is due to the anatomical characteristics of this bony structure, close to the facial cavities, covered by a meningeal lining and containing many vascular and nervous components. The choice of operative approach is guided by careful review of imaging data as well as limitations and risks of each approach. Sometimes, combined approaches in one or two stages are necessary. Only an adequate knowledge of each approach can allow the best surgical choice and limit the complications.

[Imaging of skull base tumors in adults]. / Imagerie des tumeurs de la base du crâne de l'adulte.

The skull base is divided into three parts: anterior, central and posterior. Numerous foramina are located in the skull base and transmit important neurovascular structures. Numerous types of tumor can be observed at the skull base. They are classified as anterior, central and posterior skull base tumors. They are also divided into three groups according to their origin: tumors arising from the skull base itself, intracranial tumors and extracranial tumors invading the skull base. Imaging is very important for diagnosis, treatment and follow-up of patients with skull base tumors. Magnetic resonance imaging is the most useful modality as it visualizes the lesion on different planes and permits the planning of therapy. Computed tomography depicts the osseous lesions more precisely and may be necessary before surgery. Catheter angiography is now in most cases replaced by magnetic resonance angiography. Interventional neuroradiology is necessary if the lesion is highly vascularized or if a vessel is encased in the tumor.

Thromboembolic events after endovascular treatment of unruptured intracranial aneurysms in two patients with antiphospholipid-antibody syndrome.

Antiphospholipid antibodies (APAs) are circulating immunoglobulins associated with a hypercoagulable state. The antiphospholipid syndrome combines APAs and clinical manifestations, including arterial or venous thromboses and/or recurrent spontaneous fetal loss. The main risk incurred by endovascular treatment of intracranial aneurysms is the occurrence of thromboembolic events. We report two cases of patients with antiphospholipid syndrome who developed thromboembolic complications after the endovascular treatment of unruptured intracranial aneurysms.

Neuroimaging features of spontaneous intracranial hypotension.

We reviewed the cranial MRI and radionuclide cisternograms of four adults with postural headache indicating spontaneous intracranial hypotension (SIH). All four underwent clinical and radiological follow-up. MRI showed diffuse, thin meningeal enhancement; bilateral subdural fluid collections; and morphological abnormalities secondary to "sagging" of the brain. Radionuclide cisternography revealed direct or indirect signs of leakage of cerebrospinal fluid (CSF) along the spinal axis, and the symptoms resolved after the leak treated by epidural injection of blood at a level indicated by the cisternogram. The diffuse meningeal enhancement decreased but persisted on follow-up MRI, although the patients were asymptomatic. All morphologic abnormalities resolved during 3-5 months follow-up.

Intracranial aneurysm associated with relapsing polychondritis.

We describe a 50-year-old man with relapsing polychondritis (RP) involving auricular cartilage, uveitis and hearing loss, who had an aneurysm of the anterior cerebral artery. Intracranial aneurysm is a rare manifestation of RP.

Follow-up of intracranial aneurysms treated with detachable coils: comparison of gadolinium-enhanced 3D time-of-flight MR angiography and digital subtraction angiography.

PURPOSE: To compare three-dimensional (3D) time-of-flight magnetic resonance (MR) angiography with digital subtraction angiography (DSA) in the follow-up of intracranial aneurysms treated with selective endovascular placement of detachable coils. MATERIALS AND METHODS: Sixty-eight consecutive patients with intracranial aneurysms were included in the prospective study. The goal was to evaluate 3D time-of-flight MR angiography versus DSA for the detection of a residual aneurysm neck or residual flow inside the coil mesh. RESULTS: Eighty-one MR angiographic and 83 DSA examinations were performed; 15 patients were examined with both modalities twice. MR angiography was not possible in two patients. In another patient, the quality of MR angiography was not sufficient to assess the treated aneurysm. In 72 of the remaining 80 MR angiographic and DSA examinations, there was good correlation between the two modalities. In 54 cases, neither image type showed remnants or recurrence, but in 18, both showed residual aneurysm. In eight cases, the MR angiographic and DSA results differed. In one of these cases, MR angiography depicted residual aneurysm but DSA depicted an arterial loop. In seven cases, a small (<3-mm) remnant was not detected at MR angiography. CONCLUSION: Because very small aneurysm remnants or recurrences probably are not clinically important, MR angiography is an option for following up intracranial aneurysms treated with detachable coils and may partly replace DSA.

Giant-cell tumour involving the cranial vault: imaging and treatment.

A giant-cell tumour involving the cranial vault was diagnosed in a 37-year-old man who presented with a large swelling at the vertex. The role of imaging in the diagnosis and treatment of this tumour is described. On CT and MRI the appearances were nonspecific and the diagnosis was established by histological examination after removal of the tumour. A preoperative angiogram showed a tumour blush and before surgery, embolisation was performed via the percutaneous and transarterial routes.

Postoperative aneurysm remnants: endovascular treatment as an alternative to further surgery.

Because further surgery on postoperative aneurysm remnants can be difficult and lead to significant morbidity and mortality, endovascular treatment, using controlled detachable coils, was performed in three patients with such remnants. The endovascular approach was technically more difficult in these cases than in previously untreated patients. In one case, the "remodelling" technique was necessary. Given the successful outcome in these patients, endovascular treatment can be proposed as an alternative to another operation, when further surgery appears too risky or is refused by the patient.

Percutaneous biopsy of the thoracic and lumbar spine: transpedicular approach under fluoroscopic guidance.

Eighteen patients with vertebral lesions located in the thoracic or lumbar spine underwent percutaneous biopsy performed via a transpedicular approach under fluoroscopic guidance. This technique led to an accurate diagnosis in 16 cases (89%). No complications were encountered. For percutaneous lumbar and thoracic vertebral biopsy, the transpedicular approach is a safe and accurate alternative to the posterolateral approach.

Local intraarterial fibrinolysis of thromboemboli occurring during endovascular treatment of intracerebral aneurysm: a comparison of anatomic results and clinical outcome.

PURPOSE: We describe our therapeutic strategy and correlate the anatomic results and clinical outcomes in patients who received immediate fibrinolytic therapy for thromboembolic complications occurring during endovascular treatment of an intracerebral aneurysm. METHODS: The medical records and angiographic examinations of 19 patients were reviewed. All endovascular procedures were performed with the patients under general anesthesia and fully heparinized. Thirteen patients received an intravenous bolus injection of aspirin. Thromboemboli occurred during catheterization or insertion of embolic material (Guglielmi detachable coils or mechanical detachable spirals) or in the first hours after the intervention. Clot distribution was within the MCA territory in 14 patients, the ACA in three patients, and the basilar trunk in two patients. A continuous intraarterial injection of urokinase was administered immediately, either superselectively distal to the thrombus or selectively within or closely proximal to the thrombus. In nine cases, chemical lysis was combined with mechanical clot fragmentation. Initial anatomic recanalization as well as clinical outcome at 3 months were evaluated. RESULTS: Ten patients showed complete recanalization and nine patients showed partial recanalization. Fourteen patients had a good clinical recovery. One patient was moderately disabled and two were severely disabled according to their scores on the Glasgow outcome scale. Two patients died, one as a consequence of the preexisting subarachnoid hemorrhage and the other because of a large intracerebral hematoma that developed after fibrinolysis. Of the 14 patients with a good clinical outcome, nine exhibited complete recanalization and five partial recanalization. CONCLUSION: Pharmacological thrombolysis seems to be a safe and efficient therapy that facilitates the natural fibrinolytic process, increasing the rate of recanalization in thromboembolic events. Clot fragmentation and superselective drug infusion appear to improve the rate of recanalization. Complete recanalization increases the chance of a better clinical outcome; however, clinical outcome does not always correspond to recanalization and vice versa.

Combined neurosurgical and neuroradiological treatment of a complex superior sagittal sinus dural fistula: technical note.

OBJECTIVE AND IMPORTANCE: Dural arteriovenous fistulas of the superior sagittal sinus (SSS) account for 8% of intracranial dural fistulas. Their association with a thrombosis of the posterior part of the SSS is rare. In such cases, the usual neurosurgical and endovascular approaches cannot provide a good technical solution for treatment of the lesion, and a combined neurosurgical and neuroradiological approach is therefore needed. CLINICAL PRESENTATION: A 68-year-old man presented with rapidly evolving dementia. Cerebral angiography revealed a dural arteriovenous fistula of the SSS associated with thrombosis of the posterior part of the SSS. Various endovascular and neurosurgical approaches failed to cure the fistula. INTERVENTION: A burr hole was drilled in the frontal region, in the neurosurgical room. The patient was then transferred to the angiographic room, and the SSS was occluded using free spirals. CONCLUSION: This procedure led to a complete anatomic cure of the fistula, and a slow clinical improvement was observed.

The endovascular approach in the management of patients with multiple intracranial aneurysms.

To investigate the role of endovascular treatment we performed a retrospective study of our patients with multiple intracranial aneurysms seen in our institution between October 1992 and March 1995. This period was chosen to study a homogeneous group of patients since the appearance of controlled detachable coils, and to obtain the largest number of patients with angiographic follow-up of the aneurysms treated. We studied 53 patients with a total of 128 aneurysms, in 46 of whom we treated 67 aneurysms by the endovascular approach. Of these, 5 aneurysms in 3 patients were treated by occlusion of the parent vessel and 62 aneurysms in 43 patients with coils, 52 with Guglielmi detachable coils and 10 with mechanically detachable spirals. Complete occlusion was obtained in 58 aneurysms, and partial occlusion in 9. The therapy caused permanent neurological deficit in 3 cases (6.5%), and there was 1 case of rebleeding (incomplete occlusion of the aneurysm). No deaths occurred. All aneurysms were treated in 29 of the 53 patients. Endovascular procedures were used for 16 patients (30%), surgery was performed in 1 patient (2%) and the two were combined in 12 (23%). In 23 of 53 cases (43%), unruptured aneurysms were left untreated, usually because of their small size. In 1 patient with unruptured aneurysms, the endovascular approach failed and the patient refused surgery.