Morphological features of the venous bed of the heart of the Baikal seal

The article describes the features of venous blood outflow from the heart in the Baikal seal. The objects for the study were corrosion preparations of 11 hearts of the Baikal seal aged from 1 month to 10 years. In our research we used the methods of preparation, filling of vessels with the use of "Kudo" mounting foam, photographing and sketching the branching of vessels. It was established that in the Baikal seal, the outflow of venous blood occurs through the prominent coronary sinus and the large, intermediate, oblique vein of the left atrium, the middle and right heart veins that flow into it. In 18.2% of hearts, a coronary valve was found at the border of the great heart vein and the coronary sinus. The great heart vein begins above the apices of the heart and is formed from the fusing of the 6-11 collateral veins of the wall of the right ventricle, the venous pericardial plexus, and 9-16 branches on the side of the left ventricle. The most variable is the intermediate (marginal) branch, which in most cases has only one branch, however, in 18.2% of cases there are two ones or in 9.1% of cases, there are intermediate branches with a common trunk. The middle vein of the heart is located in the sub-sinus sulcus and anastomoses with the branch of the great vein of the heart, in 9.1% of cases, the valve of the coronary sinus was found at the border with the coronary sinus. The right veins of the heart have 5-6 branches, among which the marginal ones are the most prominent. 27.3% of Baikal seals have a venous sinus formed from the fusion of the middle and right coronary veins, as well as a duct connecting the large cardiac vein with this sinus.

Endoscopic-assisted paramedian infratentorial supracerebellar approach for pineal cyst – How I do it Video clip

Background: The endoscopic supracerebellar-infratentorial (SCIT) approach is a viable method to access pathology of the posterior incisura, but a narrow working space and frequent instrument conflict can potentially limit its surgical efficacy. We planned an endoscopic-assisted paramedian infratentorial supracerebellar approach for pineal cyst. Case Description: Patient was placed in prone position under general anesthesia. His head was rotated to the left side slightly. The location of the transverse sinus was detected with navigation system. A 5 cm linear skin incision was performed, and a 2 cm craniectomy was performed about 2 cm left of the median. The transverse sinus was little bit exposed. Dura was incised in a U-shaped incision with the transverse sinus at the base. The endoscope was advanced along with the culmen. At that time, we observed inferior and superior vermian vein. After reaching to the thick arachnoid near by galenic system, the arachnoid membrane was incised and the CSF was evacuated. After that, the cerebellum became soft and the surgical corridor became large. The arachnoid membrane was incised widely. Pineal cyst, precentral cerebellar vein, bilateral internal occipital vein and great vein of galen were exposed. There were some small veins on the pineal cyst, but the adhesion was not so severe. The cyst was dissected from these small veins. There was no adhesion between the cyst and surrounding brain except for the pineal recess. Bilateral ICV was seen behind the cyst. There was feeding artery and draining vein on the antero-lateral part of the cyst. These vessels were coagulated and cut, then the cyst was removed. After the removal, we confirmed complete removal of the cyst and hemostasis. Conclusion: Endoscopic-assisted paramedian SCIT approach for pineal cyst in prone position is a reasonable and efficient access for posterior third ventricular lesions. The learning curve, maneuverability in small space, and instrument conflict limit efficacy.

Duplex Sonographic Diagnosis of Perinatal Hemorrhagic Stroke

Children are particularly at risk for stroke in the neonatal period. Neonatal hemorrhagic stroke is rarer than ischemic stroke. The incidence is 40.7/100 000 live births. Hemorrhagic stroke is caused by a disruption in venous drainage usually due to local thrombosis. As a result of the nonspecific clinical symptoms in this age group, diagnosis is usually made too late. The only relatively specific symptom is a cerebral seizure during the first week of life. Therefore, stroke should be ruled out by diagnostic imaging in the case of any seizure in the first days of life. The diagnostic method of choice is MRI, but it is not always available. Most neonatal strokes can be detected with high-resolution duplex ultrasound. Hemorrhagic stroke appears as a focal increase in echogenicity in a venous drainage area on ultrasound. The corresponding venous drainage can be visualized with duplex ultrasound and measured with spectral Doppler. Hemorrhagic stroke of the internal veins appears as hemorrhage in the basal ganglia. Venous thrombosis must be ruled out in every cerebral hemorrhage of unclear origin in an otherwise healthy term newborn. In the case of hemorrhagic infarction of the basal ganglia, both internal cerebral veins, the great vein of Galen, and the straight sinus must be examined with Doppler ultrasound. Doppler ultrasound should be used to differentiate between complete occlusion and severe stenosis. The recanalization of vessels and the morphological consequences of hemorrhagic stroke can be visualized in the further course.

Distension of central great vein decreases sympathetic outflow in humans

Classic canine studies suggest that central great vein distension evokes an autonomic reflex tachycardia (Bainbridge reflex). It is unclear whether central venous distension in humans is a necessary and sufficient stimulus to evoke a reflex increase in heart rate (HR), blood pressure (BP), and muscle sympathetic nerve activity (MSNA). Prior work from our laboratory suggests that limb venous distension evokes a reflex increase in BP and MSNA in humans. We hypothesized that in humans, compared with the limb venous distension, inferior vena cava (IVC) distension would evoke a less prominent increase in HR and MSNA. IVC distension (monitored with ultrasonography) was induced by two methods: 1) head-down tilt (HDT, N = 13); and 2) lower-body positive pressure (LBPP, N = 10). Two minutes of HDT induced IVC distension (Δ2.6 ± 0.2 mm, P < 0.001, ∼27% in cross-sectional area), slightly increased mean BP (Δ2.3 ± 0.7 mmHg, P = 0.005), decreased MSNA (Δ5.2 ± 0.8 bursts/min, P < 0.001, N = 10), and did not alter HR ( P = 0.37). LBPP induced similar IVC distension, increased BP (Δ2.0 ± 0.7 mmHg, P < 0.01), and did not alter HR ( P = 0.34). Thus central venous distension leads to a rapid increase in BP and a subsequent fall in MSNA. Central venous distension does not evoke either bradycardia or tachycardia in humans. The absence of a baroreflex-mediated bradycardia suggests that the Bainbridge reflex is engaged. Clearly, this reflex differs from the powerful sympathoexcitation peripheral venous distension reflex described in humans.

Color Doppler Ultrasound and MRI Findings of Vein of Galen Malformation in a Newborn, a Case Report.

The Vein of Galen aneurysmal malformation (VGAM) is a rare intracranial arteriovenous anomaly that has usually been diagnosed prenatally. We reported a near term boy, 2,140 grams body weight, with a large VGAM, who was diagnosed prenatally by color Doppler ultrasound. After birth, his APGAR scores were 2, 4, and 8, respectively. An emergency cranial ultrasound was performed promptly when his vital sign began to be stable. The image revealed a huge dilatation of the great vein of Galen, measured about 1.9 x 2.0 x 3.8 cm. in diameter, with mixed venous and arterial flow profiles. Abnormal dilatation of the right internal carotid artery, and circle of Willis were also identified and likely to be an arterial feeder to choroidal artery which directly draining into the great vein of Galen. MRI, MRA, and MRV of the brain were performed on the following day and also showed a huge aneurysmal dilatation of a median vein of prosencephalon (precursor of the great vein of Galen) and marked dilatation of falcine sinus. Torcular herophili, both transverse / sigmoid sinuses and both internal jugular veins showed abnormal dilatation on MRA and MRV. Endovascular transarterial embolization was planned to performe on this patient but his vital sign was not stable. He finally expired from severe congestive heart failure after 5 days of life.

Selective Transvenous Coil Embolization of Dural Arteriovenous Fistula

We herein report three cases of dural arteriovenous fistula (DAVF) in which the venous outlet immediately adjacent to the fistula was selectively embolized. Case 1: A 69-year-old man presented with a subarachnoid hemorrhage (SAH). Angiography demonstrated a DAVF in the left superior petrous sinus. Case 2: A 59-year-old woman presented with dizziness. Angiography demonstrated a DAVF adjacent to great vein of Galen. The DAVF drained through the great vein of Galen with retrograde leptomeningeal venous drainage (RLVD). The basal vein of Rosenthal was enhanced from the great vein of Galen. Case 3: A 51-year-old man presented with an occipital seizure. Angiography demonstrated a DAVF adjacent to the left side of the superior sagittal sinus with RLVD. All three cases were successfully treated by the selective embolization of the venous outlet immediately adjacent to the fistula. Therefore, selective embolization preserved normal venous return.