Role of Magnetic Resonance Venogram as a Tool in Planning for Various Neurosurgical Operations

Objectives and methodology: Exact localization of superficial cortical veins is very important in planning for avoiding venousinjuries. Cod liver oil capsules were placed on anterior and posterior ends of medial and lateral border of the tumor at scalpaccording to location of tumor and thus tumor boundaries were marked. Then 3DCEMRV and 2DTOF images were taken andthen superficial cortical vein studied in marked area for comparison between both modalities of MRV and planning of surgeryfor avoiding venous injury.Results: Most of the cases were in age group 16-60 years (89%). Most common clinical manifestation was headache (86.2%)and meningioma (58.2%) was found to be most common pathology. Clear depiction and morphology of superficial corticalvein was observed in 58 cases (100%) in 3DCEMRV as compared to 2DTOF 24 cases (41.3%) P <0.001S. Clear depictionand morphology of superior sagittal sinus was observed in 58 cases (100%) in 3DCEMRV as compared to 2DTOF 33 cases(60.3%) P <0.001S. In post operative CT Head, we found 6 (10.3%) cases of venous infarction. 7 patients (12%) developedmotor weakness post operatively. In 3 cases, post operative MRV were done and found no venous injury.Conclusion: This study showed that preoperative marking of tumor area and associated venous anatomy with the help of codliver oil capsule and MRV was very helpful in planning the surgery and to avoid injury of the vein. 3DCEMRV was found to bebetter modality than 2DTOF for delineation of veins.

Estudo da técnica de venografia dos dígitos de vacas / Study of Venography technique in digits of cows

O objetivo deste estudo foi descrever a técnica de venografia retrógrada podal em vacas, comparando os acessos da veia digital dorsal comum III com a digital comum II ou IV, nos membros torácicos e pélvicos, mediante a administração de dois diferentes volumes de contraste. Foram utilizados 53 membros torácicos e pélvicos de 14 vacas, com o torniquete de borracha posicionado a 5cm proximal aosparadígitos. Administraram-se 10mL do diatrizoato de meglumina em 24 membros (grupo 1), sendo 13 na veia digital dorsal comum III pelo acesso 1 (A1) e 11 na digital II ou IV no acesso 2 (A2). No grupo 2, administraram-se 20mL em 29 membros, sendo 15 pelo A1 e 19 pelo A2. Após a administração do contraste, as radiografias foram repetidas a cada 20 segundos até 120 segundos. O grau de preenchimento vascular foi maior no grupo 2, não diferindo entre membros e acessos venosos. Conclui-se que a administração de 20mL de contraste apresentou melhor preenchimento vascular e radiopacidade, não havendo diferença entre 20 e 120 segundos após a administração do contraste na qualidade radiográfica, independentemente do acesso venoso.(AU)

The aim of this study was to describe the technique of retrograde venography foot in cows, comparing the approaches of the dorsal common digital vein III with the digital commons II or IV, thoracic and pelvic by administering two different volumes of contrast members. Fifty three fore and hindlimbs of 14 cows were used, a rubber tourniquet was placed at 5cm above accessory digit. Diatrizoatemeglumine was administered at 10mL to 24 members (group 1), 13 dorsal common digital vein III for access 1 (A1), and 11 digital II or IV access 2 (A2). In group 2 20mL was administered to 29 members, 15 by 19 in A1 and A2. After contrast administration, the radiographs were repeated every 20 seconds until 120 seconds. The degree of vascular filling was greater in group 2, independent of venous access, member or moment. There was no significant difference in the degree of radiopacity of radiographic images when compared to the venous access, time and a member of both groups. We conclude that administration of 20mL of contrast showed better vascular filling and radiopacity, with no difference between 20 and 120 seconds after contrast administration in independent radiographic quality venous access.(AU)

Visualization of Soft Tissue Venous Malformations of Head and Neck with 4D Flow Magnetic Resonance Imaging / 신경중재치료의학

Evaluation of hemodynamics in venous malformation (VM) in the head and neck area is done by direct puncture venography before alcohol sclerotherapy, but it is difficult due to a variable degree of filling in from the artery and filling out into the draining vein. We present our preliminary experience of 4D MRI to evaluate VM hemodynamics. Four patients with venous malformation in the maxillofacial area underwent both 4D MRI and direct puncture venography before alcohol sclerotherapy. To find out appropriate velocity encoding (VENC) for VM, we applied 5-50 cm/sec VENC. Significant high-flow foci demonstrated by phase changes in magnitude images were compared with lesion types shown on a direct puncture venogram. Detection of flow in VM was possible in magnitude images or phase-difference images when VENC was set to less than 30 cm/sec. Appropriate VENC for VM was regarded as less than 5 cm/sec. High-flow areas in the dilated venous sac demonstrated focal spots or linear band-like areas on phase changes of 4D MRI. Appropriate VENC application was mandatory to detect flow in VM. Flow information on 4D MRI provided flow information in VM which was not detected on a direct puncture venogram in the compartmentalized lesion and thus can make alcohol sclerotherapy safer.

Técnica venográfica contrastada in vivo dos dígitos de ovinos e caprinos / Contrast venography technique in vivo of the digits of sheep and goat

Foram utilizados 10 membros torácicos e pélvicos de ovinos e caprinos hígidos, de raça e sexo variados, com idade entre dois e quatro anos e peso corpóreo médio de 53kg. A porção distal dos membros torácicos e pélvicos foi submetida à técnica venográfica contrastada e à contagem vascular venosa da mesma região, em ambas as espécies. Não foram observadas diferenças numéricas em relação às veias entre machos e fêmeas, nem entre os membros direito e esquerdo da mesma espécie. Os ovinos possuem maior número de veias em relação aos caprinos. A técnica venográfica distal anterógrada de ambos os membros em ovinos e caprinos se mostrou aplicável revelando a vasculatura distal e podal, a comunicação entre os vasos venosos e a quantidade dos vasos presentes na região.

Ten forelimbs and hindlimbs of healthy sheep and goats, of varied breeds and gender with ages ranging between two and four years and an average body weight of 53kg were used in the study. The forelimbs and hindlimbs underwent a contrasted venography of the distal region. No numerical differences were observed in relation to veins between males and females and between the left and right members of the same species. Sheep had more veins than goats. The antiretrograde venography technique of both limbs in sheep and goats was proved to be applicable, showing the vasculazation of the distal region of the foot, the communication between the vessels and the quantity of vessels.

Thrombosis of the Superior Sagittal Sinus in Behcet's Disease With Vascular and Enteric Involvements

We report superior sagittal sinus thrombosis as a central nervous system presentation of Behcet's disease in a patient with peripheral vascular and enteric involvement. The main symptoms were headache and horizontal diplopia due to intracranial hypertension. T1-weighted MRI with gadolinium enhancement revealed a similar pattern of the "empty delta sign" that is usually seen on brain CT. A magnetic resonance venogram revealed filling defects resulting from the thrombosis. These features are helpful for the noninvasive diagnosis of sagittal sinus thrombosis.

Significance of Cerebral Venography in Surgery of Petroclival Meningiomas

OBJECTIVE: A thorough understanding of the related venous structure is mandatory for successful removal of the petroclival meningiomas. This study was planned to investigate the guideline for safe ligation and incision of transverse or sigmoid sinuses and the importance of drainage pattern of vein of Labb in surgical removal of petroclival meningiomas. MATERIALS AND METHODS: The authors reviewed the venogram of the consecutive 37 cases of petroclival meningiomas and retrospectively analyzed their surgical findings. The drainage pattern of confluence of Herophili was classified as Type A(confluent and equal on both sides), Type B(confluent and non-dominant on tumor side), Type C(confluent and dominant on tumor side) and Type D(unilateral drainage only) as these findings gave the information on safe ligation and resection of the sinus. Usefulness of intraoperative test clamping of sinus for safe ligation was also reviewed. The vein of Labb was analyzed with respect to its draining point and its collaterals to other superficial veins. RESULTS: Contraindications of the sinus ligation and resection according to the drainage pattern at the confluence of Herophili were Type C(n=10, 27%)and Type D(n=4, 11%). Patients with Type A(n=12, 32%)and Type B(n=11, 30%) were tolerable to sinus ligation ipsilateral to tumor, if the test clamping proved to be safe. Identification of no brain swelling, after intraoperative test clamping of the sinus for more than 30 minutes performed in 7 out of 11 cases, was a reliable indicator of safe sinus ligation. The drainage pattern of the vein of Labb, especially low-lying type, could predict the possibility of postoperative hemorrhage and infarction. Its drainage into tentorium or superior petrosal sinus, however, made the transtentorial approach impossible, leading to restricted operative field. CONCLUSION: For a successful removal of the petroclival meningiomas preoperative venogram should be examined carefully. The extent of exposure in a planned approach can be estimated by analyzing the variation of sinuses and the drainage pattern of vein of Labb.

Clinical Significance of Preoperative Venogram in Arterio-Venous Shunt Operation

The most common limiting factor in arterio-venous fistula operation (AVF) is the lack of a suitable native vein. So preoperative assessment of venous system is essential for successful results. But simple physical examination alone is not enough to assess in many cases. To evaluate difference between venogram results with physical examination, 20 patients (group A) imaged with venogram preoperatively compared with 20 patients (group B) who examined only physically. In group A, all patients palpated thrill in immediate post operation and one patient revealed fistula occlusion within post operative 2 months. In group B 4 patients revealed failed fistula within 24 hours and 5 fistula failed in 2 months. Twelve patients (>50%) of group A showed different results in venogram compared with physical examination, which influenced type of operation. Physical examination alone was not enough to assess venous system and venogram provided valuable information in AVF constructive surgery.