Simultaneous Monitoring of the Middle Cerebral and Basilar Arteries to Detect Right-to-Left Shunts Using Transcranial Doppler by Agitated Saline Administration

Transcranial Doppler (TCD) is an easy, non-invasive, and real-time monitoring device for detecting right-to-left shunts (RLS). Nonetheless, it has limited benefits in patients with poor temporal windows. Therefore, we aimed to investigate whether the basilar artery (BA) window was as effective as the middle cerebral artery (MCA) in detecting RLS during TCD monitoring. Overall, we enrolled 344 patients with stroke, transient ischemic attack, headache, or dizziness. MCA and BA were monitored using a modified headset. To investigate the feasibility of the suboccipital window in detecting RLS, we instituted an evaluation tool with three tiers to evaluate microembolic signals (MESs) during TCD monitoring. Tier 1: TCD monitoring of the MCA (bilaterally) in the resting state, tier 2: TCD monitoring of the MCA (bilaterally) while performing the Valsalva maneuver, and tier 3: TCD monitoring of the index MCA and BA while performing the Valsalva maneuver. In tiers 2 and 3, a high agreement rate of 0.8076 and 0.8068 (p<0.001), respectively, on the weighted kappa index, and a high intra-class correlation coefficient of 0.9822 and 0.9860 (p<0.001), respectively, were observed on detecting MESs. Our data suggests that the BA window is as effective as the MCA window for detecting RLS on TCD.

Our Experience in the Treatment of Vertebrobasilar Insufficiency Due to Cervical Spine Disorders

This article defines vertebra-related causes of vertebrobasilar insufficiency in patients with the signs of tortuosity of segment VI of the VA. The aim of this study is to present the results of diagnostics of discirculatory phenomena in the vertebrobasilar system and to show their importance for differentiated surgical treatment of stenotic lesions of segment V1 of VA in pathological disorders of cerebral circulation in the VBS caused by osteochondrosis of the cervical spine. The following traditional methods are used in diagnostics: Doppler ultrasonography, multispiral computed tomography with contrast enhancement. Also using developed by the author method for determining VA reactivity and circulatory insufficiency in the vertebrobasilar system (VBS). Based on our methodology and criteria, patients were selected for different types of surgical treatment with clinical outcome prediction following interventions on the arteries of the VBS. To determine the pathologies of the intracranial segments of the vertebral and basilar arteries, taking into account the pathways of collateral compensation in the VBS, cerebral angiography is recommended before surgery on the arteries of the VBS. Reconstructive techniques used on segment VI of the VA will predictably show the best long-term clinical results. The excision of a tortuous segment VI of the VA may be effective in obtaining reliable results of successful interventions in the early postoperative period. The conservative treatment of the patients with multiple VBD lesions is possible. early outcomes of their use are satisfactory.

Congenital Agenesis of Both Vertebro-Basilar Artery-A Rare Case Report

Vertebral and basilar arteries are the major blood suppliers of the brain. They supply nearly one-third of the brain. Congenital absence of these arteries is a rare condition. Usually, this condition presents with stroke like presentation. This is a case presentation of a 40-year-old lady who was diagnosed as congenital agenesis of vertebra-basilar arteries. This lady was presented with intraventricular hemorrhage. Subsequently the diagnosis was made by cerebral angiogram.

Vertebrobasilar Contribution to Cerebral Arterial System of Dromedary Camels (Camelus dromedarius)

It is hypothesized that in the “more highly evolved” mammals, including the domesticated mammals, that the brainstem and the cerebellum receive arterial blood through the vertebrobasilar system whilst the internal carotid arteries primarily supply the forebrain. In camels, the arterial blood supply to the brain differs from that of ruminants since the internal carotid artery and the rostral epidural rete mirabile (RERM) are both present and the basilar artery contributes a significant proportion of cerebral afferent blood. In this study, we described the anatomical distribution of the vertebrobasilar system arterial supply in the dromedary. Secondly, we determined the direction of blood flow within the vertebral and basilar arteries using transcranial color doppler ultrasonography. Thirdly, we quantified the percentage arterial contributions of the carotid and vertebrobasilar systems to the dromedary brain. Fifty-five heads of freshly slaughtered male Omani dromedaries aged 2–6 years were dissected to determine the distribution and topography of the arterial distribution to the brain. Their anatomical orientation was assessed by casting techniques using epoxy resin, polyurethane resin and latex neoprene. The epoxy resin and polyurethane resin casts of the head and neck arteries were used to measure the diameter of vertebrobasilar arterial system and carotid arterial system at pre-determined locations. These arterial diameters were used to calculate the percentage of blood supplied by each arterial system. The vertebrobasilar system in dromedary camels consists of paired vertebral arteries that contribute to the ventral spinal artery and basilar artery at multiple locations. In most specimens the vertebral artery was the primary contributor to the basilar artery compared to that of the ventral spinal artery. In four specimens the ventral spinal arteries appear to be the dominant contributor to the basilar artery. Transcranial color doppler ultrasonography confirmed that the direction of blood flow within the vertebral and basilar arteries was toward the brain in animals examined in ventral recumbency and when standing. The vertebrobasilar system contributes 34% of the blood supply to the brain. The vertebrobasilar system is the exclusive supply to the medulla oblongata, pons and cerebellum.

Valproic Acid Reduces Vasospasm through Modulation of Akt Phosphorylation and Attenuates Neuronal Apoptosis in Subarachnoid Hemorrhage Rats

Aneurysmal subarachnoid hemorrhage (SAH) is a devastating emergent event associated with high mortality and morbidity. Survivors usually experience functional neurological sequelae caused by vasospasm-related delayed ischemia. In this study, male Sprague-Dawley rats were randomly assigned to five groups: sham (non-SAH) group, SAH group, and three groups with SAH treated with different doses of valproic acid (VPA) (10, 20, 40 mg/kg, once-daily, for 7 days). The severity of vasospasm was determined by the ratio of cross-sectional areas to intima-media thickness of the basilar arteries (BA) on the seventh day after SAH. The BA showed decreased expression of phospho-Akt proteins. The dentate gyrus showed increased expression of cleaved caspase-3 and Bax proteins and decreased expression of Bcl-2, phospho-ERK 1/2, phospho-Akt and acetyl-histone H3 proteins. The incidence of SAH-induced vasospasm was significantly lower in the SAH group treated with VPA 40 mg/kg (p < 0.001). Moreover, all groups treated with VPA showed reversal of the above-mentioned protein expression in BA and the dentate gyrus. Treatment with VPA upregulated histone H3 acetylation and conferred anti-vasospastic and neuro-protective effects by enhancing Akt and/or ERK phosphorylation. This study demonstrated that VPA could alleviate delayed cerebral vasospasm induced neuro-apoptosis after SAH.

High-Grade Stenosis of a Traumatic Brachiocephalic Pseudoaneurysm and the Change in Cerebral Blood Flow Assessed With Transcranial Doppler Ultrasound

This is a case report of a 35-year-old female pedestrian struck by a semi-truck. computed tomographic angiography (CTA) revealed a pseudoaneurysm at the proximal brachiocephalic artery measuring 1.8 cm in cranio-caudal length and 1.2 × 0.6 cm transverse. Just distal to the pseudoaneurysm, there was severe luminal narrowing caused by either a dissection flap or mural thrombus. Due to profound left-sided weakness, transcranial Doppler ultrasound was performed which demonstrated “hesitant” waveforms in the right middle cerebral and right vertebral arteries secondary to proximal obstruction. Hesitant waveforms display mid-systolic velocity deceleration and may also be referred to as the “bunny” waveform. Emboli monitoring of the right middle cerebral and basilar arteries were positive for active embolization

Clival Meningioma Removal through a Suboccipital Retrosigmoid Approach: Operative Video and Technical Nuances

Background Clival meningiomas are challenging lesions that need to be managed according to the displacement of the adjacent structures. Lateral skull base approaches are needed to achieve their radical removal; however, they are associated with significant morbidity, especially when the tumor involves the basilar artery, its perforators, brainstem, and lower cranial nerves. Design This is a case of a 79-year-old female patient, diagnosed with a large lower clival meningioma after suffering from headaches. It was offered a conservative treatment but on serial MRI, an increase in the meningioma's size was observed, so it was decided to remove the meningioma using a left suboccipital retrosigmoid approach. Settings On a left three-quarter prone position, with facial nerve, auditory brainstem response, lower cranial nerves, and motor-evoked potentials and somatosensory-evoked potentials neurophysiologic monitoring, a right suboccipital retrosigmoid craniotomy with opening of the foramen magnum was performed, giving enough lateral visualization of the tumor. Broad base tumor pushing backward and aside the vertebral and basilar arteries, cranial nerves (7th–12th), and the brainstem was exposed and removed. Results Near total resection of the meningioma was achieved, leaving a microscopic residual in the entry points of the low cranial nerves without complications. There was no neurological deficit after the surgery. Postoperative MRI revealed no signs of residual tumor. Conclusion: In this case, the regular retrosigmoid approach, extended into the foramen magnum was enough for the removal of this pure clival meningioma.The link to the video can be found at: https://youtu.be/3d6Uj4gjmDU.

CHANGES IN THE MORPHOMETRIC PARAMETERS OF THE BASILAR ARTERY WALL WHEN ITS COURSE IS GEOMETRICALLY ABNORMAL (KINKING AND COILING OF THE BASILAR ARTERY)

Цель - выявить закономерность изменения морфометрических параметров базилярной артерии при изменении геометрической конфигурации ее хода с формированием острого угла, спирали или петли. Материал и методы. Исследовали 16 нефиксированных макропрепаратов головного мозга. Анатомию базилярной артерии изучали методами макро-и микропрепарирования, проводили ангиоморфометрию с последующей обработкой результатов исследования. Результаты. В ходе ангиоморфометрии 16 базилярных артерий в 68,75 % случаев выявлен нормальный линейный ход сосуда. Величина показателя упругих свойств составила 0,33±0,01. В 31,25 % случаев выявлено изменение геометрической конфигурации хода базилярной артерии. В 40 % случаев от общего числа единиц с патологическим ходом сосуда формируется кинкинг базилярной артерии, в 60 % случаев - койлинг. Величина показателя упругих свойств составила 0,34±0,01, что существенно не отличается от средних значений для артерий мышечного типа. Исследование длины, толщины стенки, наружного диаметра и диаметра просвета сосудов показало значительное превышение данных показателей в сравнении с таковыми при нормальным линейном ходе артерий. Выводы. Данные, полученные в ходе исследования, свидетельствуют об увеличении наружного диаметра базилярной артерии, толщины сосудистой стенки и внутреннего просвета в случае образования кинкинга или койлинга. Objective - to reveal the pattern of changes in the morphometric parameters of the basilar artery when the geometric configuration of its course alters with the formation of an acute angle, spiral or loop. Material and methods. We studied 16 non-fixed human brain specimens. Anatomy of the basilar artery was studied by methods of macro- and micro-preparation, angiomorphometry was carried out with subsequent processing of the results of the study. Results. During angiomorphometry of 16 basilar arteries, normal straight course of the vessel was detected in 68,75 % of the cases. The value of the elastic properties index was 0,33±0,01. In 31,25 % of cases, a change in the geometric configuration of the course of the basilar artery was revealed. The basilar artery kinking was formed in 40 % and coiling - in 60 % of the total number of all cases with abnormal vessel course. The value of the elastic properties index was 0,34±0,01, which is not significantly different from the average values for muscle-type arteries. The study of the length, wall thickness, outer diameter and lumen diameter of the vessels showed a significant excess of these parameters in comparison with the vessels with normal linear course. Conclusions. The data obtained during the study indicate an increase in the outer diameter of the basilar artery, as well as an increase in the thickness of the vascular wall and the inner lumen in the case of kinking or coiling.