Cranial dural arteriovenous shunts: selection of the ideal lesion for surgical occlusion according to the classification system.

BACKGROUND: The types of cranial dural arteriovenous fistulae (cDAVFs) that constitute good surgical candidates are unclear despite the use of classifications. We aimed to compare the DES classification with other classification schemes in identifying "ideal lesions for surgery." The DES scheme is based on two features: the level of the shunt (BVS, bridging vein shunt; DSS, dural sinus shunt; ISS, isolated sinus shunt; EVS, emissary vein shunt) and the type of leptomeningeal venous reflux (LVR) (direct, exclusive, strained). METHODS: In this observational cohort study, the angiographies of 20 consecutive patients treated over 1 year were analyzed retrospectively. We defined cDAVFs as ideal for surgery, if cure may be achieved by disconnecting the arterialized draining vein through a single craniotomy. To evaluate the performance of each classification scheme in identifying the "ideal lesion for surgery," we carried out a sensitivity analysis of the Borden, Cognard, and DES schemes. RESULTS: Eight lesions were Borden type 3 and 1 type 2, and 11 type 1. According to Cognard, 2 lesions were type IV, 2 type III, 1 type IIa+b, 11 type I, and 4 lesions could not be clearly classified. According to the DES scheme, 8 lesions were DSS, 4 BVS, 3 ISS, and 5 EVS. All 4 lesions classified as BVS in the DES were ideal lesions for surgery (sensitivity, specificity, PPV, NPV 100%). Not all high-grade lesions according to Borden were good surgical candidates. CONCLUSION: The DES scheme, as opposed to other classifications, facilitates the therapeutic decision-making especially for selecting candidates for surgery.

Combining monoenergetic extrapolations from dual-energy CT with iterative reconstructions: reduction of coil and clip artifacts from intracranial aneurysm therapy.

PURPOSE: To compare and to combine iterative metal artifact reduction (MAR) and virtual monoenergetic extrapolations (VMEs) from dual-energy computed tomography (DECT) for reducing metal artifacts from intracranial clips and coils. METHODS: Fourteen clips and six coils were scanned in a phantom model with DECT at 100 and 150SnkVp. Four datasets were reconstructed: non-corrected images (filtered-back projection), iterative MAR, VME from DECT at 120 keV, and combined iterative MAR + VME images. Artifact severity scores and visibility of simulated, contrast-filled, adjacent vessels were assessed qualitatively and quantitatively by two independent, blinded readers. RESULTS: Iterative MAR, VME, and combined iterative MAR + VME resulted in a significant reduction of qualitative (p < 0.001) and quantitative clip artifacts (p < 0.005) and improved the visibility of adjacent vessels (p < 0.05) compared to non-corrected images, with lowest artifact scores found in combined iterative MAR + VME images. Titanium clips demonstrated less artifacts than Phynox clips (p < 0.05), and artifact scores increased with clip size. Coil artifacts increased with coil size but were reducible when applying iterative MAR + VME compared to non-corrected images. However, no technique improved the severe artifacts from large, densely packed coils. CONCLUSIONS: Combining iterative MAR with VME allows for an improved metal artifact reduction from clips and smaller, loosely packed coils. Limited value was found for large and densely packed coils.

Missed Anterior Inferior Cerebellar Artery Aneurysm Mimicking Vestibular Neuritis-Clues to Prevent Misdiagnosis.

We discuss a case with combined vestibulocochlear and facial neuropathy mimicking a less urgent peripheral vestibular pattern of acute vestibular syndrome (AVS). With initial magnetic resonance imaging read as normal, the patient was treated for vestibular neuropathy until headaches worsened and a diagnosis of subarachnoid hemorrhage was made. On conventional angiography, a ruptured distal right-sided aneurysm of the anterior inferior cerebellar artery was diagnosed and coiled. Whereas acute vestibular loss usually points to a benign peripheral cause of AVS, combined neuropathy of the vestibulocochlear and the facial nerve requires immediate neuroimaging focusing on the cerebellopontine angle. Imaging should be assessed jointly by neuroradiologists and the clinicians in charge to take the clinical context into account.

The collateral circulation in pediatric moyamoya disease.

PURPOSE: The descriptions of collateral circulation in moyamoya have so far been a mixture of topography-based and vessels' source-based analyses. We aimed to investigate the anatomy and systematize the vascular anastomotic networks in pediatric moyamoya disease. METHODS: From a series of 25 consecutive complete angiographic studies of newly diagnosed children with moyamoya, 14 children had moyamoya disease and 11 were diagnosed with moyamoya syndrome, i.e., moyamoya angiopathy with some additional concomitant systemic disease. We retrospectively analyzed the arterial branches supplying the moyamoya anastomotic networks, their origin, course, location, and connections with the recipient vessels. RESULTS: We describe four types of anastomotic networks in children with moyamoya disease, two superficial-meningeal and two deep-parenchymal. As superficial-meningeal, we defined the leptomeningeal and the durocortical networks. Apart from the previously described leptomeningeal network observed in the convexial watershed zones, we report on the basal temporo-orbitofrontal leptomeningeal network. The second superficial-meningeal network is the durocortical network, which can be basal or calvarian in location. We define as deep-parenchymal networks the nonpreviously described subependymal network and the inner striatal and inner thalamic networks. The subependymal network is fed by the intraventricular branches of the choroidal system and diencephalic perforators, which at the level of the periventricular subependymal zone, anastomose with medullary-cortical arteries as well as with striatal arteries. The inner striatal and thalamic networks are constituted by intrastriatal connections among striatal arteries and intrathalamic connections among thalamic arteries when the disease compromises the origin of one or more sources of their supply. CONCLUSION: The previously inexplicitly described "moyamoya abnormal network" in pediatric moyamoya disease can be described as a composition of four anastomotic networks with distinct angioarchitecture. A better understanding of the collateralization in moyamoya may help in defining a new staging system of the disease with clinical relevance.

Langer-Giedion syndrome associated with congenital dural arterio-venous fistula.

Langer-Giedion syndrome (LGS) is a rare disease caused by deletion of chromosome 8q23.3-q24.11. Clinical manifestations include among others multiple exostoses, short stature, intellectual disability, and typical facial dysmorphism. Dural arterio-venous shunts (DAVS) in the pediatric age are rare lesions, which have been classified into three types: dural sinus malformations (DSM), infantile type DAVS (IDAVS), and adult type DAVS (ADAVS). We report a case of a patient with a known LGS who was diagnosed with complex intracranial dural AV fistula at the age of 20. An association between LGS and intracranial dural AV fistulas has to our knowledge never been reported before.

Cranial dural arteriovenous shunts. Part 3. Classification based on the leptomeningeal venous drainage.

The commonly used Borden and Cognard classification systems for the prediction of clinical behavior of cranial dural arteriovenous shunts focus on the venous drainage, particularly the presence of leptomeningeal venous drainage, and on the direction of flow, particularly the presence of retrograde flow. In addition, the latter includes ectasia and spinal drainage as criteria of two distinct grades. However, none of the above classifications (a) differentiates direct from exclusive leptomeningeal venous drainage, (b) considers cortical venous congestion as a factor potentially associated with an aggressive clinical course, and (c) anticipates ectasia in shunts with a mixed dural-cortical venous drainage (type 2). In this study, we analyzed the angiographic images of 107 consecutive patients having a cranial dural arteriovenous fistula with leptomeningeal venous drainage, based on a newly developed scheme. This scheme, symbolized with the acronym "DES," groups the dural shunts according to three factors: directness and exclusivity of leptomeningeal venous drainage and signs of venous strain. According to the combination of the three factors, eight different groups were distinguished. All analyzed cases could be assigned to one of these groups. Directness of leptomeningeal venous drainage expresses the exact site of the shunt (bridging vein vs sinus wall), whereas exclusivity expresses venous outlet restrictions. All bridging vein shunts had a direct leptomeningeal venous drainage. Almost all bridging vein shunts and all "isolated" sinus shunts had an exclusive leptomeningeal venous drainage. Venous strain, manifested as ectasia and/or congestion, denotes the decompensation of the cerebral venous system due to the shunt reflux. The comparison of the presented concept with the currently used classifications highlighted the advantages of the former and the weaknesses of the latter.

Cranial dural arteriovenous shunts. Part 4. Clinical presentation of the shunts with leptomeningeal venous drainage.

Cranial dural arteriovenous fistulae have been classified into high- and low-risk lesions mainly based on the pattern of venous drainage. Those with leptomeningeal venous drainage carry a higher risk of an aggressive clinical presentation. Recently, it has been proposed that the clinical presentation should be considered as an additional independent factor determining the clinical course of these lesions. However, dural shunts with leptomeningeal venous drainage include a very wide spectrum of inhomogeneous lesions. In the current study, we correlated the clinical presentation of 107 consecutive patients harboring cranial dural arteriovenous shunts with leptomeningeal venous drainage, with their distinct anatomic and angiographic features categorized into eight groups based on the "DES" (Directness and Exclusivity of leptomeningeal venous drainage and features of venous Strain) concept. We found that among these groups, there are significant angioarchitectural differences, which are reflected by considerable differences in clinical presentation. Leptomeningeal venous drainage of dural sinus shunts that is neither direct nor exclusive and without venous strain manifested only benign symptoms (aggressive presentation 0%). On the other end of the spectrum, the bridging vein shunts with direct and exclusive leptomeningeal venous drainage and venous strain are expected to present aggressive symptoms almost always and most likely with bleeding (aggressive presentation 91.5%). Important aspects of the above correlations are discussed. Therefore, the consideration of leptomeningeal venous drainage alone, for prediction of the clinical presentation of these shunts appears insufficient. Angiographic analysis based on the above concept, offers the possibility to distinguish the higher- from the lower-risk types of leptomeningeal venous drainage. In this context, consideration of the clinical presentation as an additional independent factor for the prediction of their clinical course seems superfluous and possibly misleading. Topography is connected to the clinical presentation of the dural shunts inasmuch as the former determines the venous anatomy and the angioarchitectural features of the lesions.

Cranial dural arteriovenous shunts. Part 2. The shunts of the bridging veins and leptomeningeal venous drainage.

Leptomeningeal venous drainage of cranial dural arteriovenous fistulae is the most important determinant of adverse clinical course. Factors that predispose to its occurrence have not been adequately addressed in the literature. In the present study, we investigated the relation of shunt location to the development of leptomeningeal venous drainage, with regard to the bridging veins. Angiographic data of 211 consecutive patients with cranial dural arteriovenous fistulae treated over 19 years were analyzed. Dural shunts with leptomeningeal venous drainage were found in 107 patients; of these, 71 patients had pure leptomeningeal venous drainage (Borden type 3). The angioarchitecture of the shunt, including pattern of arterial feeders, relation with the bridging veins, primary venous drainage, and venous outflow restrictions were recorded. After analysis of the 71 Borden type 3 shunts with exclusive leptomeningeal venous drainage, three patterns emerged. The commonest was the fistula engaging a bridging vein that had lost its connection to the parent sinus into which it previously drained; it was characterized by an arterial network of feeders converging onto the wall of a bridging vein, with leptomeningeal venous reflux. The other patterns were those of "isolated" sinus segment characterized by arterial feeders converging on to the wall of the dural sinus with leptomeningeal venous reflux following the opacification of the sinus and fistulae in the vicinity of the cribriform plate with two subtypes. The main angioarchitectural features of the 36 Borden type 2 shunts with mixed sinusal-cortical venous drainage were the presence of a diffuse arterial network of vessels converging onto a site in the wall of the dural sinus, with leptomeningeal venous reflux following the opacification of the sinus. In this group, four exceptions were noticed with arterial feeders converging onto a bridging vein and having a mixed venous drainage to the cortical venous system and the sinuses. We concluded that the exact location of the shunt with regard to the bridging veins is a key factor in the development of leptomeningeal venous drainage. Cranial dural arteriovenous fistulae (CDAVFs) of either Borden type 2 or 3 do not constitute a homogeneous group. The great majority of these shunts present thrombotic phenomena.

Cranial dural arteriovenous shunts. Part 1. Anatomy and embryology of the bridging and emissary veins.

We reviewed the anatomy and embryology of the bridging and emissary veins aiming to elucidate aspects related to the cranial dural arteriovenous fistulae. Data from relevant articles on the anatomy and embryology of the bridging and emissary veins were identified using one electronic database, supplemented by data from selected reference texts. Persisting fetal pial-arachnoidal veins correspond to the adult bridging veins. Relevant embryologic descriptions are based on the classic scheme of five divisions of the brain (telencephalon, diencephalon, mesencephalon, metencephalon, myelencephalon). Variation in their exact position and the number of bridging veins is the rule and certain locations, particularly that of the anterior cranial fossa and lower posterior cranial fossa are often neglected in prior descriptions. The distal segment of a bridging vein is part of the dural system and can be primarily involved in cranial dural arteriovenous lesions by constituting the actual site of the shunt. The veins in the lamina cribriformis exhibit a bridging-emissary vein pattern similar to the spinal configuration. The emissary veins connect the dural venous system with the extracranial venous system and are often involved in dural arteriovenous lesions. Cranial dural shunts may develop in three distinct areas of the cranial venous system: the dural sinuses and their interfaces with bridging veins and emissary veins. The exact site of the lesion may dictate the arterial feeders and original venous drainage pattern.

Intra-arterial administration of papaverine during mechanical thrombectomy for acute ischemic stroke.

BACKGROUND: The use of stent retrievers for mechanical thrombectomy in acute ischemic stroke may induce significant vasospasm, which at the early phases of reperfusion may be crucial for rethrombosis of the recanalized vessel. We aimed to study whether the use of intra-arterial papaverine in selected cases of vasospasm was associated with improved cerebral perfusion, arterial reocclusion, or increased hemorrhagic complications. METHODS: We retrospectively studied 9 consecutive patients with large artery acute occlusion, treated with stent retriever and intra-arterial papaverine. Onset to administration of intravenous recombinant tissue-plasminogen activator time, baseline National Institute of Health Stroke Scale, time to reperfusion, number of passes of the stent retriever, modified Rankin Scale score at discharge, postprocedural hemorrhage, onset to reperfusion time, papaverine dose, and thrombolysis in cerebral infarction grade were recorded in all patients. RESULTS: After papaverine administration, the caliber of the infused arteries and their flow was increased in all cases. In none of the treated cases a reocclusion occurred after papaverine infusion. In one of the studied patients (11%), a parenchymal bleeding occurred 36 hours postoperatively. CONCLUSIONS: This small study suggests that intra-arterial infusion of papaverine for the treatment of cerebral vasospasm after mechanical thrombectomy in acute ischemic stroke is effective and safe.

The recurrent artery of Heubner in routine selective cerebral angiography.

INTRODUCTION: Heubner's recurrent artery (RAH) in brain selective catheter angiograms (digital subtraction angiography, DSA) was evaluated. METHODS: Bilateral cerebral angiograms with antero-posterior, lateral and oblique frontal views were obtained in 100 neurological patients aged from 5 to 90 years. Site of origin, type of course and branching of the RAH were studied. Three groups were obtained: arteries with solely the horizontal segment visible, horizontal and vertical segments visible and horizontal and vertical with intraparenchymal branches visible. RESULTS: A total of 24 RAHs were recognised in 20 patients: 7 arose from the A1, 5 from the anterior cerebral artery (ACA)-anterior communicating artery (Acom), 11 from the A2, whereas in 1 case, the segment of origin from the ACA could not be identified. Seventeen arteries arose from the lateral wall of the ACA and seven from the superior wall of the A1 segment of the ACA. The RAH was bilaterally seen in 3 patients and unilaterally in 17 with one double RAH. Five RAHs were visible only after contrast injection in the contralateral internal carotid artery. A horizontal segment was visible in 7 arteries, a horizontal followed by a vertical segment without visible intraparenchymal branching pattern was seen in 6 and a horizontal and vertical segment with visible intraparenchymal branching pattern was seen in 11. In five, the artery made a half loop with an inferior-convex curve just before the vertical segment, and in two cases, a full loop was observed. CONCLUSION: The RAH was recognised in 12% of the hemispheres of the present series of neurological patients studied with DSA.

Endovascular treatment of 170 consecutive cranial dural arteriovenous fistulae: results and complications.

This study aims to evaluate a single-center experience with endovascular treatment of cranial dural arterievenous fistulae (CDAVF). The clinical and radiological records of 170 consecutive patients harboring a CDAVF and treated endovascularly in a 16-year period were reviewed. A variety of data related to demographics, features of the lesion, treatment, outcome, and follow-up were analyzed with emphasis to the results and complications. Half of the lesions had cortical venous drainage (CVD) in the initial angiographic investigation, whereas 26 % had exclusively CVD. Sixty-seven percent of our patients presented with benign symptoms and 33 % with aggressive symptoms. In 60.5 % of the patients with benign lesion (without CVD), an anatomic cure in the immediate postinterventional angiogram without complication or permanent morbidity was achieved, whereas 69 % of the patients with aggressive lesions (with CVD) had an anatomic cure in the postinterventional final angiogram with all permanent-morbidity cases belonging to this group. The average of endovascular operation sessions per patient was 1.2. In a mean follow-up period of 2.8 years, the overall complete occlusion rate was 85.5 % (78 % for the benign group and 89.5 % for the aggressive group) and clinical cure and/or improvement rate of 93 %. The operative mortality was zero, and permanent neurologic morbidity was 2.3 %. In 73 % of our cases, N-butyl cyanoacrylate (NBCA) was used as the only or main embolic material. Endovascular embolization is the treatment of choice for CDAVF. High rates of good anatomical and clinical results, associated with very low operative complication rate can be achieved with few embolization sessions. Although mastering of a permanent embolic material is important, the therapeutic strategy should be individulized and not material based.

Silicone models as basic training and research aid in endovascular neurointervention--a single-center experience and review of the literature.

The rapid development and wider use of neurointerventional procedures have increased the demand for a comprehensive training program for the trainees, in order to safely and efficiently perform these procedures. Artificial vascular models are one of the dynamic ways to train the new generation of neurointerventionists to acquire the basic skills of material handling, tool manipulation through the vasculature, and development of hand-eye coordination. Herein, the authors present their experience regarding a long-established training program and review the available literature on the advantages and disadvantages of vascular silicone model training. Additionally, they present the current research applications of silicone replicas in the neurointerventional arena.

Outcomes of Mechanical Thrombectomy for Acute Ischemic Stroke in Cancer Patients: A Single-Center Experience and Meta-Analysis.

Background and Objectives: The published data about mechanical thrombectomy (MT) in cancer patients is sparse. We present our institutional experience in this clinical scenario, and a meta-analysis. Methods: The baseline data, procedural data, clinical and radiological outcomes of MT were analyzed and compared among three groups of stroke patients: controls, patients with active malignancy (AM), and patients with history of malignancy (HOM). A meta-analysis of 12 studies was conducted to address the differences between controls and AM patients regarding selected outcomes. Results: The 3 groups (controls, AM, HOM) showed significant differences regarding previous history of stroke or TIA (7.8% vs 10.5% vs 38.5%, p = 0.006), alcohol consumption (0.9% vs 10.5% vs 0.0%, p = 0.04), thrombophilia (1.7% vs 15.8% vs 7.7%, p = 0.009), deep venous thrombosis (0.4 vs 26.3% vs 7.7%, p = 0.005). The AM group had significantly higher rates of sICH (3.5% [controls] vs 21.1% [AM] vs 0.0% [HOM], p = 0.007), and mortality at 3 months (27.5% [controls] vs 61.5% [AM] vs 40.0% [HOM] vs, p = 0.032). The control and HOM groups had significantly better functional independence at 3 months (52.1% [controls] vs 15.4% [AM] vs 60.0% [HOM], p = 0.032).In the meta-analysis, the AM arm showed significantly higher mortality during hospitalization (n = 6, OR 95% CI = 3.03 [1.62, 5.64]), and at 3 months (n = 10, OR 95% CI = 4.33 [2.80, 6.68]), and significantly lower rates of 3 months functional independence (mRS = 0-2) (n = 10, OR 95% CI = 0.47 [0.32, 0.70]). No significant difference was found in sICH rates (n = 6, pooled OR 95% CI = 2.03 [0.83, 4.95]). Discussion: Endovascular MT is technically successful and reasonably safe in treating AIS from LVO in active malignancy patients. However, the causes and implications of sICH require further investigation. Despite technical success, these patients experience poor clinical outcomes, and the long-term benefits of MT remain uncertain.

Persistent ventral ophthalmic artery associated with supraclinoid internal carotid artery aneurysm: case report and review of the literature.

A persistent ventral ophthalmic artery arising from the A1 segment of the anterior cerebral artery associated with an ipsilateral asymptomatic supraclinoid internal carotid artery (ICA) aneurysm is extremely rare. This variation and association were thoroughly documented by digital substraction angiography (DSA) and 3-dimensional rotational angiography (3DRA) in a 49-year-old female with polycystic kidney disease. A short review of the related literature is also presented.

Unassisted and multiple microcatheter coiling of distal basilar aneurysms: Outcomes and literature review.

PURPOSE: The best treatment for distal basilar artery aneurysms is controversial. We aimed to review our single-centre experience with coil embolisation of aneurysms at this location and compare it with the surgical and endovascular literature. METHODS: Forty-two aneurysms in a distal basilar location in 42 consecutive patients (15 ruptured and 27 unruptured) were treated endovascularly from 2010 to 2015. Unassisted single and multiple microcatheter coil embolisation alone was used in all cases. We studied our immediate and long-term anatomical results, operative complications, and outcome. RESULTS: The immediate angiographic results showed complete occlusion in 34 (81%), a neck remnant in seven (16.6%) and a residual aneurysm in one patient (2.4%). There were two thromboembolic events (4.7%) without clinical sequelae; therefore, the operative morbidity and mortality were zero.Three patients with ruptured aneurysms (7.1%) died due to complicated vasospasm. Thirty-nine patients (93%) had clinical and MR imaging follow-up (mean 32.3 months ± 18.6, range from 12 to 66 months). There was recanalization in 30.8% with a retreatment rate of 15.3% and no new bleedings. The aneurysm size was the most important predictor of early anatomical outcome and recurrence. CONCLUSION: Unassisted and multiple microcatheter coiling is a safe treatment for distal basilar aneurysms. Early anatomical results and recurrence depend on the aneurysm size. Morbidity and mortality are lower and recurrence rates are higher in comparison with clipping or other adjunctive endovascular techniques.

Thrombectomy-Related Emboli: Direct Aspiration versus Stent Retriever Thrombectomy for Acute Ischemic Stroke: Our Experience and Literature Review.

OBJECTIVE: Thrombectomy-related emboli (TRE) represent a potentially dangerous complication of thrombectomy procedures for acute ischemic stroke. The aim of this study was to compare the rate of TRE in aspiration thrombectomy (ASP) and stent retriever thrombectomy techniques. METHODS: We retrospectively compared clinical and radiologic outcomes of 2 groups of consecutive patients with stroke, ASP group and SRT group, with TRE rates as the primary study endpoint. Emboli were classified as either affected territory emboli or unaffected territory emboli (uTRE). Relevant literature was also reviewed. RESULTS: The ASP group had better rates of successful recanalization (97.1% vs. 77.1%, P = 0.02), mean number of passes per case (2.0 vs. 3.3, P = 0.04), and mean operative time (34.1 minutes vs. 84.8 minutes, P < 0.0001). Thrombectomy technique (ASP vs. SRT) did not appear to predict rates of either affected territory emboli (odds ratio [OR] = 1.24, 95% confidence interval [CI] 0.33-4.63, P = 0.74) or uTRE (OR = 5.67, 95% CI 0.60-53.42, P = 0.13). Longer operative time was linked to higher uTRE rates (OR = 1.03, 95% CI 1.01-1.05, P = 0.02). ASP technique (OR 0.1, 95% CI 0.01-0.88; P = 0.04) and shorter operative time (OR = 0.98, 95% CI 0.97-0.99, P = 0.03) were linked to better rates of successful recanalization. CONCLUSIONS: The applied thrombectomy technique (ASP vs. SRT) is not an independent predictor of TRE rates. Operative time tends to affect the rates of uTRE and successful recanalization. The ASP technique offers higher rates of successful recanalization in less operative time.

A White Matter Fiber Microdissection Study of the Anterior Perforated Substance and the Basal Forebrain: A Gateway to the Basal Ganglia?

BACKGROUND: Studies detailing the anatomy of the basal forebrain (BF) from a neurosurgical perspective are missing. OBJECTIVE: To describe the anatomy of the BF and of the anterior perforated substance (APS), the BF emphasizing surgical useful anatomical relationship between surface landmarks and deep structures. METHODS: White matter fiber microdissection was performed on 5 brain specimens to analyze the topographic anatomy of the APS and expose layer-by-layer fiber tracts and nuclei of the BF. RESULTS: The APS, as identified anatomically, surgically, and neuroradiologically, has clear borders measured 23.3 ± 3.4 mm (19-27) in the mediolateral and 12.5 ± 1.2 mm (11-14) in the anteroposterior directions. A detailed stratigraphy of the BF was performed from the APS up to basal ganglia and thalamus allowing identification and dissection of the main components of the BF (septum, nucleus accumbens, amygdala, innominate substance) and its white matter tracts (band of Broca, extracapsular thalamic peduncle, ventral amygdalohypothalamic fibers). The olfactory trigone together with diagonal gyrus and the APS proper is a relevant superficial landmark for the basal ganglia (inferior to the nucleus accumbens, lateral to the caudate head, and medial to the lentiform nucleus). CONCLUSION: The findings in our study supplement available anatomic knowledge of APS and BF, providing reliable landmarks for precise topographic diagnosis of BF lesions and for intraoperative orientation. Surgically relevant relationships between surface and deep anatomic structures are highlighted offering thus a contribution to neurosurgeons willing to perform surgery in this delicate area.

Multiple anomalies in the origin and course of vertebral arteries and aberrant right subclavian artery in a child with moyamoya syndrome.

Here we report, for the first time, a combination of five-vessel aortic arch, anomalous origin of the right vertebral artery (VA) from the common carotid artery (CCA), an aberrant right subclavian artery (SCA), and bilateral symmetrical segmental agenesis of VAs.In this case report, we present a patient with moyamoya syndrome (MMS) and Down syndrome (DS) who has bilateral symmetrical segmental agenesis of VAs, left VA originating from aortic arch and anomalous origin of right VA arising from CCA in combination with an aberrant right SCA. Therefore, five vessels are originating from aortic arch. Here, we report, for the first time, a combination of five-vessel aortic arch with an aberrant right SCA and symmetrical segmental agenesis of both VAs. The possible embryological mechanisms of the anomalies as well as an relation with MMS and DS are discussed.

Multiple anomalies in the origin and course of vertebral arteries and aberrant right subclavian artery in a child with moyamoya syndrome.

Here we report, for the first time, a combination of five-vessel aortic arch, anomalous origin of the right vertebral artery (VA) from the common carotid artery (CCA), an aberrant right subclavian artery (SCA), and bilateral symmetrical segmental agenesis of VAs.In this case report, we present a patient with moyamoya syndrome (MMS) and Down syndrome (DS) who has bilateral symmetrical segmental agenesis of VAs, left VA originating from aortic arch and anomalous origin of right VA arising from CCA in combination with an aberrant right SCA. Therefore, five vessels are originating from aortic arch. Here, we report, for the first time, a combination of five-vessel aortic arch with an aberrant right SCA and symmetrical segmental agenesis of both VAs. The possible embryological mechanisms of the anomalies as well as an relation with MMS and DS are discussed.