Diego San Millán

Hôpital de Sion · Radiology

Cerebral developmental venous anomalies are the most frequently encountered cerebral vascular malformation, and as such, are frequently reported as fortuitous findings in computed tomography (CT) and magnetic resonance imaging (MRI) studies. Developmental venous anomalies (DVAs) are generally considered extreme anatomical variations of the cerebral...

Here we describe an anatomic structure that takes the form of a venous channel (VC) within the two layers of the lateral wall of the cavernous sinus (CS). Colored gelatin was injected in both superficial middle cerebral veins (SMCV) of 29 human specimens. When a SMCV terminated into the CS, the latter was dissected giving particular attention to it...

Passing from the supine to the upright position favors cerebral venous outflow into vertebral venous systems rather than into the internal jugular veins. We sought to determine venous connections between dural venous sinuses of the posterior cranial fossa and craniocervical vertebral venous systems. Corrosion casts of the cranial and cervical venou...

The termination of the superficial middle cerebral vein is classically assimilated to the sphenoid portion of the sphenoparietal sinus. This notion has, however, been challenged in a sometimes confusing literature. The purpose of the present study was to evaluate the actual anatomic relationship existing between the sphenoparietal sinus and the sup...

This article provides a comprehensive description of the morphology of the human petrosquamosal sinus (PSS) derived from original observations made on 13 corrosion casts of the cranial venous system combined with routine clinical imaging studies in two patients. The PSS is not a rare finding in the adult human. In particular, continuous development...

Background: Classic cerebrotendinous xanthomatosis (CTX; OMIM #213700) manifests with chronic diarrhea, juvenile cataracts, tendon xanthomas and neurological symptoms. It is due to biallelic inactivation of CYP27A1 wich leads to cholestanol accumulation in the central nervous system, eyes and tendons. Less commonly, the disease can present in youn...

Background: Classic cerebrotendinous xanthomatosis (CTX; OMIM #213700) manifests itself in childhood with chronic diarrhea, juvenile cataracts, tendon xanthomas and neurological symptoms. Biallelic inactivation of CYP27A1 is responsible for cholesterol 27-hydroxylation, leading to cholestanol accumulation in the central nervous system, eyes and ten...

Background Spinal digital subtraction angiography (DSA) exposes patients and operators to substantial amounts of radiation. Antiscatter grid (ASG) removal is used to decrease radiation exposure but may reduce image quality. Purpose To determine whether ASG removal during spinal DSA in adults reduces radiation dose while maintaining diagnostic image...

Background Isolated cerebral deep medullary vein thrombosis has been described in the setting of hemorrhagic periventricular white matter lesions in preterm and full-term neonates, but to the best of our knowledge, has never been reported in adults. We present two cases of isolated thrombosis of the superior striate vein occurring in adults that co...

Optico-cerebral syndrome

Most spontaneous CSF leaks (SCSFL) are associated with an underlying pseudotumor cerebri syndrome (PTCS). Treatment generally includes surgical leak repair and PTCS correction, as untreated PTCS carries a risk of recurrence. We describe a 72-year-old woman with rhinorrhea, aural fullness, and posterior nasal drip. CT and MRI showed signs of CSF hyp...

Background and purpose: Transverse sinus stenosis can lead to pseudotumor cerebri syndrome by elevating the cerebral venous pressure. The occipital emissary vein is an inconstant emissary vein that connects the torcular herophili with the suboccipital veins of the external vertebral plexus. This retrospective study compares the prevalence and size...

Background: Sequestered disc fragments may present as a lesion with peripheral enhancement on magnetic resonance imaging. When located in the psoas muscle compartment, this finding could mimic an abscess. Case description: We describe a case of a 52-year-old man who returned from Togo after 2 years of living in precarious conditions. He was afeb...

Thoracic vertebral arteries are anastomotic chains similar to cervical vertebral arteries but found at the thoracic level. Descending thoracic vertebral arteries originate from the pretransverse segment of the cervical vertebral artery and curve caudally to pass into the last transverse foramen or the first costotransverse space. Ascending thoracic...

Introduction: Brain herniations (BH) into arachnoid granulations (AG) in dural venous sinuses and calvarium have rarely been reported in the literature. Methods: MRIs of 38 patients with BH into AG (BHAG) were retrospectively analyzed. Locations of BHAG, gyrus/lobe of the herniated brain, parenchymal abnormalities of the BH, and clinical and rad...

Background: Before the development of the adult ophthalmic artery (OA), the primitive maxillary artery (MA), the primitive dorsal OA, and the primitive ventral OA contribute to the vascularization of early ocular structures, whereas the primitive olfactory artery (OlfA) forms in the vicinity of the optic vesicle. These vessels are involved in seve...

Dural arteriovenous fistulas (DAVFs) of the hypoglossal canal (HCDAVFs) are rare and display a complex angiographic anatomy. Hitherto, they have been referred to as various entities (for example, "marginal sinus DAVFs") solely described in case reports or small series. In this in-depth review of HCDAVF, the authors describe clinical and imaging fin...

Cerebral blood flow is provided by the paired internal carotid arteries (ICAs) and vertebral arteries (VAs). The intradural branches of the ICA supply the anterior cerebral circulation (i.e., cerebral hemispheres, including basal ganglia) and the orbit; these branches include the ophthalmic artery (OA), posterior communicating artery (PComA), anter...

Solitary fibrous tumours (SFTs) are rare WHO grade I mesenchymal neoplasms that were first described in the visceral pleura. A wide variety of locations of SFT have been reported but only twelve cases of intramedullary solitary fibrous tumour. We report a case of thoracic spinal cord SFT. A 49-year-old woman presented with clinical signs of dorsal...

Objectives: Characterize the phenotypic features of smooth muscle cells (SMCs) in the wall of human saccular intracranial aneurysms (sIAs). Methods and Results: We investigated by means of immunohistochemistry the expression of the cytoskeletal differentiation markers α-smooth muscle actin (α-SMA), smooth muscle myosin heavy chains (SMMHCs), and sm...

Objectives: Characterize the phenotypic features of smooth muscle cells (SMCs) in the wall of human saccular intracranial aneurysms (sIAs). Methods and results: We investigated by means of immunohistochemistry the expression of the cytoskeletal differentiation markers α-smooth muscle actin (α-SMA), smooth muscle myosin heavy chains (SMMHCs), and...

During the past recent years, Enterobacteriaceae have supplanted Gram-positives in terms of frequent resistant bacteria seen in the outpatent setting. This change involves common opportunistic pathogens such as E. coli and K. pneumoniae. It is mainly due to the appearance and dissemination of extended-spectrum beta-lactamases (ESBL), that hydrolyse...

Spinal cord cavernous malformations (CMs) are associated with 2 types of angiographically occult "cryptic venous anomalies," which differ in location with respect to the spinal cord. The anatomic distinction between superficial and intramedullary is important in that the latter heighten the risks of CM resection. To report the observations of both...

Hypoplasia of the rostral third of the SSS is a well-known variant and constitutes the most frequent variation of the SSS after preferential drainage to one of the transverse sinuses. Our aim was to describe unilateral hypoplasia of the rostral end of the SSS. CTA performed in 100 consecutive patients studied for conditions other than dural sinus t...

A 32-year-old woman hospitalized for subarachnoid hemorrhage showed rare arterial variation on the right side with anomalous origins of the vertebral artery, aberrant subclavian artery and persistent trigeminal artery. Angiography showed the right vertebral artery to originate from the right common carotid artery, the right subclavian artery to ari...

Cerebral developmental venous anomalies (DVAs) are the most frequently encountered cerebral vascular malformation. As such, they are often observed incidentally during routine CT and MRI studies. Yet, what DVAs represent from a clinical perspective is frequently not common knowledge and DVAs, therefore, still generate uncertainty and concern amongs...

In presence of immunosuppression Cytomegalovirus (CMV) infection can cause severe and potentially fatal infection involving multiple organs. In healthy immunocompetent individuals CMV usually causes an asymptomatic or mild infection with spontaneous cure. No specific therapy is needed. Rarely, however, the primary infection can be severe with multi...

The authors present the case of an infant harboring a vein of Galen arteriovenous malformation with conspicuous cerebral calcifications that progressively regressed after staged endovascular obliteration of the lesion. The role of venous hypertension and hydrocephalus secondary to the arteriovenous shunt are discussed to explain the formation and r...

Classical anatomists have provided detailed description of the arterial collateral pathways found in the head and neck. The small branches building this intricate network are difficult to access. The arterial map inherited from the anatomists has been put to the test with detailed high-resolution vascular imaging. Superselective angiography has hel...

Multidetector CT (MDCT) is increasingly used for the investigation of neurovascular disorders, but restricted z-axis coverage (3.2 cm for 64-MDCT) currently limits perfusion to a small portion of the brain close to the circle of Willis, and precludes dynamic angiographic appreciation of the entire brain circulation. We illustrate the clinical poten...

A stenosis of the internal carotid artery may cause 10-20% of all ischemic strokes. In symptomatic patients, carotid revascularization is indicated in the presence of a stenosis 50%. in asymptomatic patients, the indication for revascularization based on randomized trials is given at > or = 60% stenosis, as long as the estimated perioperative death...

To preliminarily evaluate the feasibility and potential diagnostic utility of whole-brain perfusion computed tomography (CT) performed with a prototype 256-detector row CT system over an extended range covering the entire brain to assess ischemic cerebrovascular disease. Institutional review board approval and informed consent were obtained. Eleven...

To report a retrospective series of 84 cerebral developmental venous anomalies (DVAs), focusing on associated parenchymal abnormalities within the drainage territory of the DVA. DVAs were identified during routine diagnostic radiological work-up based on magnetic resonance imaging (MRI) (60 cases), computed tomography (CT) (62 cases) or both (36 ca...

We present a novel access for transvenous embolization of a dural arteriovenous fistula of the laterocavernous sinus through the external jugular vein and the pterygoid plexus. The anatomy of the laterocavernous sinus is reviewed, and its clinical implications discussed in light of the case of a patient whose management was modified after identifyi...

Digital subtraction angiography (DSA) is the method of reference for imaging of dural arteriovenous fistula (DAVF). The goal of this study was to analyze the value of different MR images including 3D contrast-enhanced MR angiography (MRA) with a high temporal resolution in diagnostic and follow-up imaging of DAVFs. A total of 18 MR/MRA examinations...

Cerebral embolism is the principal cause of cerebral infarction. Recently, mechanical embolectomy has been proposed as an effective method. We performed a preclinical evaluation of a new mechanical clot-retrieving wire. This clot-retrieving wire consisted of three nitinol loops at the tip of a microguidewire. These three loops could be collapsed in...

Intracranial stenting is increasingly being used to treat intracranial aneurysms and stenoses. We wanted to assess the utility of magnetic resonance angiography (MRA) in the follow-up of patients treated with various types of intracranial stents and to assess the utility of performing gadolinium-enhanced MRA. A total of 19 patients having undergone...

Knowledge of human central taste pathways is largely based on textbook (anatomical dissections) and animal (electrophysiology in vivo) data. It is only recently that further functional insight into human central gustatory pathways has been achieved. Magnetic resonance imaging studies, especially selective imaging of vascular, tumoral, or inflammato...

The purpose of this study was to evaluate whether interactions between intracranial cerebral saccular aneurysms and the perianeurysmal environment (PAE), in the form of contact constraints, influence aneurysm shape and risk of rupture. A total of 190 consecutive aneurysms during a 34-month period were retrospectively analyzed. Of these, 124 were ru...

The existence of the vein of the foramen caecum (VFC) in humans is still controversial. We present 2 patients with intracranial drainage of the nasal mucosa by a frontal cortical vein into a superior sagittal sinus, demonstrated by digital subtraction angiography. In both, the position of the intracranial passage was found to be slightly paramedian...

Il s'agit d'une étude sur l'anatomie macroscopique et radiologique des systèmes veineux de la base du crâne et de la jonction cranio-cervicale. L'utilisation de méthodes d'investigation diverses sur le cadavre et le vivant, basées d'une part sur la dissection classique et des études de corrosions veineuses, et d'autre part sur l'artériographie digi...

Objective: MDCT angiography allows fast imaging of the cerebral vessels, and its potential as a noninvasive technique to detect vascular abnormalities on the basis of morphologic changes is well established. We analyzed vascular enhancement patterns of cerebral venous structures on MDCT angiography, which enabled us to diagnose dural arteriovenous...

The presence of portal venous gas (PVG) has been reported most often in association with bowel ischemia or infarction but may result from nonischemic conditions such as bowel trauma or surgery, inflammatory or tumoral ulcerative disease, or infectious or inflammatory bowel disease. In a setting of mesenteric infarction, the presence of PVG has been...

Normal aging, leukoaraiosis (LA) and vascular disease particularly involve the human frontal lobes. We decided to investigate a population of elderly patients referred for neuroimaging because of progressive minor cognitive deficits but no dementia. They underwent conventional Magnetic resonance imaging (MRI) using axial T1 and T2-weighted imaging...

We report a case of bilateral collateral tentorial venous sinus drainage of the basal vein (of Rosenthal) (BV). The observation was made on a corrosion cast of the cerebral venous system obtained from a fresh cadaver. Radiographic correlation was obtained by performing standard X-ray imaging of the corrosion cast. Embryologic and clinical considera...

To evaluate contact between cerebral berry aneurysms and the perianeurysmal environment and to study the influence this contact has on aneurysm rupture. In a series of 76 consecutive patients, pre- and post-contrast CT images of 87 aneurysms were evaluated. Aneurysm locations were identified and aneurysms were divided into two different groups depe...

We evaluate the perianeurysmal environment and study parameters potentially influencing rupture of cerebral aneurysms. 101 consecutive aneurysm cases were retrospectively evaluated using radiological observation including imaging documents such as MR, CT and DSA studies. Aneurysm contact with perianeurysmal environment was classified and correlated...

The laterocavernous sinus (LCS) has recently been recognized as one of the major drainage pathways of the superficial middle cerebral vein (SMCV). Our purpose was to investigate the drainage pattern of the SMCV, with special emphasis on the angiographic anatomy of the LCS. The drainage pathways of the SMCV were evaluated prospectively on 100 select...

This study was undertaken to report the clinical experience with percutaneous minimal invasive vertebroplasty using polymethyl-methacrylcate (PMMA) for a consecutive group of patients. Over the period of the last 4 years, 40 patients were treated at 68 vertebral segment levels with the intention to relieve pain related to vertebral body lesions. Re...

We report the pathological findings in cases of acrylic implants obtained by direct intratumoral injection of polymethyl-methacrylate (PMMA) and N-butyl-cyano-acrylate (NBCA). Direct intratumoral injection of acrylic implants was performed for a variety of primary and secondary bone lesions. These types of treatments have been used at our instituti...

Post-exposure prophylaxis (PEP) is effective in preventing HIV infection after professional exposure. PEP is also recommended after inadvertent sexual exposure if two conditions are met: the source person is known to be HIV infected, and exposure to this person occurred only once or is accidental. The objective of this study is to describe the circ...