BACKGROUND: Pontine infarction extending to the basal surface has been reported to possess different characteristics from deep pontine infarction without extending to the basal surface. METHODS AND RESULTS: We studied 54 patients ; 30 patients with pontine infarction extending to the basal surface (group SE) and 24 patients with deep pontine infarction without extension (group DL) based on the site of the infarcts on precontrast sagittal T2WI. We assessed angiographic findings(MRA, 54; DSA, 31), risk factors, clinical features and the effectiveness of the intraluminal signal changes on spin-echo MRI in the diagnosis of occlusion or stenosis of the basilar artery. The incidence of basilar artery stenosis or occlusion in MRA or DSA in group SE(60%) was significantly more frequent than group DL(12.5%), whereas the incidence of vertebral artery stenosis or occlusion was not different between two groups. A noteworthy finding was that five patients (17%) of the group SE had not been extended to the basal surface on axial T2WI. The risk factors were similarly distributed between the two groups. The effectiveness of abnormal signal void of axial MRI was poor in the diagnosis of basilar artery occlusion or stenosis. CONCLUSIONS: Our results suggest that the two types of pontine infarction may be caused by different arterial pathology. Although the presence of abnormal flow void on MRI cannot predict the stenosis or occlusion of basilar artery, sagittal T2WI and angiographic study help to evaluate the patients with pontine infarction.
Basilar Artery* ; Constriction, Pathologic ; Diagnosis ; Humans ; Incidence ; Infarction* ; Magnetic Resonance Imaging ; Pathology ; Risk Factors ; Vertebrobasilar Insufficiency

Animals ; Basilar Artery ; Brain Ischemia ; pathology ; Brain Stem ; blood supply ; Cats ; Medulla Oblongata ; blood supply

AIMObservations on medullary ischemia region, the morphology of neurons and changes of respiration and blood pressure were made, in order to give evidences on how medullary ischemia affects respiration and circulation and give some advices on how to protect from it.

METHODSUsing cats as the experimental animals, the different parts of the basilar artery trunk were ligated. The changes in the density of blood vessels, the morphology of neurons in the brainstem, the electromyogram (EMG) of the diaphragm and the blood pressure of the femoral artery were investigated.

RESULTSThe density of blood vessels notably decreased in the medulla after ligating the basilar artery trunk. The ischemic range induced by ligation of the different parts of the basilar artery trunk overlapped, mainly locating in the medulla rostral to the obex. The soma were swelled and the Nissl bodies decreased in some of neurons in the ischemic region of medulla. The duration of inspiration (T1) and expiration (TE) shortened, respiratory frequency (RF) increased, and mean blood pressure (MBP) decreased in the experimental groups (P < 0.05).

CONCLUSIONThere is an obvious overlap of the areas in which blood supplied by different parts of the basilar artery trunk. Medullary ischemia can involve in changes of respiration and blood pressure. The ischemic damage of neurons in the medulla might be the structural basis of the changes in the respiratory and circulatory functions.

Animals ; Basilar Artery ; Blood Pressure ; Brain Ischemia ; physiopathology ; Cats ; Medulla Oblongata ; pathology ; Respiration ; Respiratory System ; blood supply ; physiopathology

BACKGROUNDThere are few studies for evaluating plaque characteristics of nonstenotic basilar arteries (BA). Our aim was to determine entire BA plaques with a three-dimensional volumetric isotropic turbo spin-echo acquisition (VISTA) and investigate the differences between the patients with and without isolated pontine infarction (IPI).

METHODSTwenty-four consecutive symptomatic patients with nonstenotic BA on time of flight magnetic resonance angiography (TOF MRA) were enrolled from China-Japan Friendship Hospital between January 2014 and December 2014. BA was classified as "normal" or "irregular" based on TOF MRA, and "normal wall", "slight wall-thickening", and "plaque" based on three-dimensional VISTA images. Outcomes from MRA and VISTA were compared. Patients were categorized as IPI and non-IPI groups based on the diffusion-weighted imaging. Clinical and plaque characteristics were compared between the two groups.

RESULTSA total of 1024 image slices including 311 (30.37%) plaque slices, 427 (41.70%) slight wall-thickening slices, and 286 (27.93%) normal wall slices for the entire BA from 23 patients were finally included for analysis. VISTA images detected plaques in all the 9 (100%) irregular MRA patients and 7 of 14 (50%) normal MRA patients. IPI was found in 11 (47.83%) patients. Compared to non-IPI group, the IPI group had a higher percentage of plaque slices (P = 0.001) and lower percentage of normal wall slices (P = 0.014) than non-IPI group.

CONCLUSIONSThree-dimensional VISTA images enable detection of BA plaques not visualized by MRA. BA plaques could be found in both the IPI and non-IPI group. However, IPI group showed plaques more extensively in BA than the non-IPI group.

Adult ; Aged ; Basilar Artery ; pathology ; Female ; Humans ; Magnetic Resonance Angiography ; Magnetic Resonance Imaging ; methods ; Male ; Middle Aged ; Plaque, Atherosclerotic ; pathology ; Pons ; pathology

OBJECTIVETo investigate the administration of far-lateral approach in lesions located anterior or anterolateral to brain stem and upper cervical spinal cord.

METHODSTwenty-three patients underwent far lateral approach, including 12 retrocondylar approach, 5 partial transcondylar approach, 3 transfacetal and partial transcondylar approach, 2 transtubercular approach and 1 complete transcondylar approach.

RESULTSTotal tumor removal was achieved in 15 patients, subtotal removal in 5 patients, 3 vertibral artery aneurysms were clipped successfully, 3 patients were given occipitalcervical fusion. There was no operative mortality. The most frequent complications were lower cranial nerve deficit, CSF leakage, injury to vertibral artery, and ischemia of brain stem, cerebellum or spinal cord. No patient presented clinical instability of the occipitocervical junction after surgery.

CONCLUSIONSThe far-lateral approach is an ideal approach to structures located ventral to cranial-cervicle junction. But some of the surgical steps are technically difficult and carry some degree of risk. The choice of approach depends on the pathological feature and degree of exposure required for effective surgical treatment. Bone removal should be quantified for individual lesion. The approach may be limited to less aggressive steps, while still achieving significant exposure and surgical space.

Adolescent ; Adult ; Aneurysm ; surgery ; Basilar Artery ; surgery ; Brain Neoplasms ; pathology ; surgery ; Female ; Follow-Up Studies ; Humans ; Male ; Microsurgery ; Middle Aged ; Neurosurgical Procedures ; methods ; Treatment Outcome ; Vertebral Artery ; surgery

BACKGROUND: The pulsatility index (PI) measured by a transcranial Doppler (TCD) has been postulated to reflect the vascular resistance that is distal to the artery being examined. Therefore, pathologies of small perforating arteries may affect the PI of the proximal artery. Microangiopathy is a common vascular complication of diabetes mellitus (DM), which may contribute to the development of small infarctions involving the perforating artery, and may be reflected on the PI. METHODS: We enrolled patients with acute cerebral infarctions who were examined by TCD, MRI, and MRA and fulfilled the following criteria: 1)an infarction of less than 2 cm size involving a single perforating arterial territory; 2)no significant arterial stenosis on MRA; and 3)no cardioembolic sources. Patients were divided into either a group with DM, or without and TCD findings were compared. RESULTS: The DM group showed higher PI than non-DM (0.99 v.s. 0.85 for the right middle cerebral artery; 1.02 v.s. 0.85 for the left middle cerebral artery; and 0.94 v.s. 0.78 for the basilar artery). The mean flow velocity was comparable between the groups. Multivariate linear regression analysis revealed that the duration of DM was a significant predictor of elevated PI of the bilateral MCA and basilar artery and that age was another significant predictor in the case of basilar artery. CONCLUSIONS: The elevated PIs in DM patients suggest the possible role of diabetic microvascular complications in the development of the lacunar infarction. The PI measurement using TCD may be a useful marker of the lacunar infarction, especially in DM patients.
Arteries ; Basilar Artery ; Cerebral Infarction ; Constriction, Pathologic ; Diabetes Mellitus ; Humans ; Infarction ; Linear Models ; Magnetic Resonance Imaging ; Middle Cerebral Artery ; Pathology ; Stroke, Lacunar* ; Vascular Resistance

Arterial Occlusive Diseases ; diagnostic imaging ; surgery ; therapy ; Basilar Artery ; diagnostic imaging ; pathology ; surgery ; Humans ; Hypothermia ; diagnostic imaging ; surgery ; therapy ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Thrombectomy

INTRODUCTIONNourishment for the brain, a highly vascular organ, is derived from a unique structure called the 'circle of Willis', which is formed by the terminal branches of the internal carotid arteries (ICAs) and basilar arteries (BAs). The circle of Willis forms an anastomotic link between the carotid and vertebrobasilar systems in the arterial supply of the brain, while the BA forms an important component of the brain's posterior circulation and supplies its many vital parts.

METHODSA study was performed on 20 brain specimens used for routine dissections at the Anatomy Department, Kasturba Medical College, in order to examine the morphology of BAs in the brain.

RESULTSIn most specimens, the position of the termination of BA was normal, although variations were present in the mode of termination. In one specimen, the BA terminated by dividing into two superior cerebellar arteries. The posterior cerebral arteries (PCAs) arose from ICAs on both sides in this specimen, and a communicating branch was present between the terminal point of the BA and PCA on the left. In another specimen, unilateral variation was seen, with the PCA arising from the ICA on the right and a posterior communicating artery arising from the PCA, connecting it with the BA. The anatomy on the left side was normal.

CONCLUSIONWe highlight the morphological aspects of the BA, the knowledge of which would help neurosurgeons safely diagnose, as well as plan and execute vascular bypass and shunting procedures for the treatment of stenosis, aneurysms and arteriovenous malformations in the posterior cranial fossa.

Basilar Artery ; abnormalities ; anatomy & histology ; Brain ; anatomy & histology ; blood supply ; Cadaver ; Carotid Arteries ; pathology ; Carotid Artery, Internal ; anatomy & histology ; Circle of Willis ; anatomy & histology ; Humans ; Posterior Cerebral Artery ; anatomy & histology

Effects of pH on vascular tone and L-type Ca2+ channels were investigated using Mulvany myograph and voltage-clamp technique in rabbit basilar arteries. In rabbitbasilar arteries, high K+ produced tonic contractions by 11+/-0.6 mN (mean+/-S.E., n=19). When extracellular pH (pHo) was changed from control 7.4 to 7.9 ([alkalosis]o), K+-induced contraction was increased to 128+/-2.1% of the control (n=13). However, K+-induced contraction was decreased to 73+/-1.3% of the control at pHo 6.8 ([acidosis]o, n=4). Histamine (10 micrometer) also produced tonic contraction by 11+/-0.6 mN (n=17), which was blocked by post-application of nicardipine (1 micrometer). [alkalosis]o and [acidosis]o increased or decreased histamine-induced contraction to 134+/-5.7% and 27+/-7.6% of the control (n=4, 6). Since high K+- and histamine-induced tonic contractions were affected by nicardipine and pHo, the effect of pHo on voltage-dependent L-type Ca2+ channel (VDCCL) was studied. VDCCL was modulated by pHo: the peak value of Ca2+ channel current (IBa) at a holding of 0 mV decreased in [acidosis]o by 41+/-8.8%, whereas that increased in [alkalosis]o by 35+/-2.1% (n=3). These results suggested that the external pH regulates vascular tone partly via the modulation of VDCC in rabbit basilar arteries.
Animals ; Arteries/*pathology ; Basilar Artery/*pathology ; Calcium/metabolism ; Calcium Channels/chemistry ; Electrophysiology ; Histamine/chemistry/metabolism ; Hydrogen-Ion Concentration ; Muscle Cells/cytology ; Muscle Contraction ; Muscle, Smooth/*pathology ; Patch-Clamp Techniques ; Potassium/chemistry/metabolism ; Rabbits ; Stress, Mechanical ; Time Factors

OBJECTIVETo study the expression change of interleukin-8 (IL-8) gene in the basilar artery of rabbit and the effect of IL-8 on the development of cerebral vasospasm induced by experimental subarachnoid hemorrhage (SAH).

METHODSThirty five healthy Japanese White Rabbits were randomly divided into saline-control group and experimental group. The experimental group was subdivided into four groups, representing day 1, 4, 7 and 14 after the first blood injection of SAH. The delayed cerebral vasospasm (DCVS) model was established by double injection of autologous blood into the cisterna magna. The expression change of cytokine IL-8 mRNA in the basilar artery was analyzed by RTPCR.

RESULTSThe expression of IL-8 gene increased on day 4-7 after the first blood injection of SAH compared with control (P< 0.001), and decreased to normal on day 14. The expression of IL-8 gene in the SAH groups were positively correlated with the degree of basilar artery stenosis (r = 0.642, P< 0.01).

CONCLUSIONThe expression level of IL-8 gene in basilar arteries was intimately associated with the degree of cerebral vasospasm, suggesting that IL-8 may play an important role in the DCVS after SAH as an immunological inflammatory factor.

Animals ; Basilar Artery ; metabolism ; Disease Models, Animal ; Gene Expression Regulation ; physiology ; Interleukin-8 ; genetics ; metabolism ; RNA, Messenger ; biosynthesis ; Rabbits ; Reverse Transcriptase Polymerase Chain Reaction ; methods ; Subarachnoid Hemorrhage ; metabolism ; pathology ; Time Factors