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Effects of artificially induced spinal cord compression on the canine cervical internal vertebral venous plexus: comparative evaluation of computed tomographic venography and digital subtraction venography
Gómez,M; Lanz,O; Jones,J; Broadstone,R; Inzana,K; Freeman,L;
Archivos de medicina veterinaria , 2008, DOI: 10.4067/S0301-732X2008000200008
Abstract: the internal vertebral venous plexus (ivvp) is a vascular network located along the vertebral canal. the present study was designed to assess variation in morphology of the cervical ivvp under experimental acute spinal cord compression in dogs. experimental spinal cord compression was induced in 9 adult dogs at c3/4 vertebral canal level using a modified angioplasty balloon catheter technique. dogs were evaluated prior to, during and post spinal cord compression using vertebral intraosseous digital subtraction venography (dsv) and computed tomographic (ct) venography. ds v demonstrated significant and immediate lack of opacification of the cervical ivvp at the site of compression. ct venography also demonstrated a similar lack of filling of the ivvp in areas of balloon compression. dsv images demonstrated the hemodynamic changes of the ivvp and their collateral veins during compression. during post-compression, dsv and ct venography images revealed that 5 dogs exhibited lack of filling of the cervical ivvp at the previously compressed area. findings show that experimental spinal cord compression induces immediate local venous morphological alteration at the involved vertebral canal area.
Antegrade pampiniform plexus venography in recurrent varicocele: Case report and anatomy review  [cached]
Vyacheslav Gendel,Ihab Haddadin,John L Nosher
World Journal of Radiology , 2011, DOI: 10.4329/wjr.v3.i7.194
Abstract: Varicoceles are often treated with percutaneous embolization, using fibered coils and sclerosing agents, with the latter targeted at occlusion of pre-existing collateral veins. While various methods of surgical and embolization treatment are available, varicoceles may still recur from venous collateralization. We present a case, where following demonstration of complete occlusion of the right and left gonadal veins, direct puncture of the pampiniform venous plexus under ultrasound guidance revealed recurrent varicoceles supplied by anastomoses from the ipsilateral saphenous and femoral veins to the pampiniform plexus. In doing so, we describe a technique of percutaneous pampiniform venography in a case where the pertinent anatomy was not easily demonstrated by other methods.
Ex vivo hepatic venography for hepatocellular carcinoma in livers explanted for liver transplantation
Kensuke Miyazaki, Akihiko Soyama, Masaaki Hidaka, Koji Hamasaki, Kosho Yamanouchi, Mitsuhisa Takatsuki, Takashi Kanematsu, Susumu Eguchi
World Journal of Surgical Oncology , 2011, DOI: 10.1186/1477-7819-9-111
Abstract: Of 105 living-donor liver transplantations (LDLT) performed up to July, 2009 at the Department of Surgery, Nagasaki University Hospital, dynamic hepatic venography was performed with contrast media under fluoroscopy for the most recent 13 cases with HCC. The presence of a tumor stain for each HCC case was evaluated and compared with the histological findings of HCC.Hepatic venography revealed a tumor stain in 2 of 13 cases (15%). Neither showed any microscopic tumor invasion of HCC into the hepatic vein. In the other 11 cases, there were 4 microscopic portal venous invasions and 2 microscopic hepatic venous invasions. No patients have shown HCC recurrence in follow-up (median period, 13 months).Using ex vivo hepatic venography, a direct connection to the hepatic vein from HCC in whole liver was revealed in 2 cases without demonstrated histopathological invasion to hepatic vein for the first time in the literature. The finding suggests that there is direct spillage of HCC cells into the systemic circulation via hepatic vein.Hepatocellular carcinoma (HCC) is one of the most common malignant tumors and the third most common cause of cancer-related death in the world [1]. Despite recent advances in treatments of HCC, the long-term survival of patients with HCC is still unsatisfactory [2]. Intrahepatic or extrahepatic recurrence usually develops, even after a curative liver resection or a total hepatectomy for orthotopic liver transplantation. There are two mechanisms that are well known for intrahepatic recurrence of HCC: multicentric carcinogenesis due to the underlying liver disease and intrahepatic metastasis with venous drainage to a portal vein [3]. On the other hand, the mechanism of extrahepatic recurrence of HCC is still controversial, with the possibility of a direct route from HCC nodules to the systemic circulation still unconfirmed. According to previous reports, the predictors for extrahepatic recurrence of HCC are the size and number of tumors, vascular in
Role of magnetic resonance venography in evaluation of cerebral veins and sinuses occlusion
EALA El Damarawy, AAM El-Nekiedy, AM Fathi, AEM Eissa, RM Darweesh
Alexandria Journal of Medicine , 2012,
Abstract: Introduction: Cerebral venous occlusion (CVO) means intraluminal obstruction by cerebral venous thrombosis (CVT) or external compression. The differential diagnosis is broad including stroke, brain capillary telangiectasia, contusion, hypertensive hemorrhage, metastases and venous vascular malformations. MRI in conjunction with MRV is considered the modality of choice in diagnosis of CVO. Objective: To assess the role of magnetic resonance venography in the evaluation of cerebral veins and sinuses occlusion. Methods: The study was conducted on 15 patients with cerebral venous occlusion and subjected to MRI and MRV. Results: The study included 13 patients with cerebral venous occlusion due to thrombosis and two patients with occlusion by tumors (meningioma). Conclusion: MRI in conjunction with MRV is considered an accurate, safe, non-invasive, nonionizing diagnostic modality in assessing CVO. It can assess parenchymal lesions and detect intraluminal small thrombi and its extension.
Effects of artificially induced spinal cord compression on the canine cervical internal vertebral venous plexus: comparative evaluation of computed tomographic venography and digital subtraction venography Efectos de la compresión de la médula espinal inducida artificialmente sobre el plexo venoso vertebral interno cervical en el perro: evaluación comparativa mediante venografia por tomografía computarizada y venografia por substracción digital
M Gómez,O Lanz,J Jones,R Broadstone
Archivos de medicina veterinaria , 2008,
Abstract: The internal vertebral venous plexus (IVVP) is a vascular network located along the vertebral canal. The present study was designed to assess variation in morphology of the cervical IVVP under experimental acute spinal cord compression in dogs. Experimental spinal cord compression was induced in 9 adult dogs at C3/4 vertebral canal level using a modified angioplasty balloon catheter technique. Dogs were evaluated prior to, during and post spinal cord compression using vertebral intraosseous digital subtraction venography (DSV) and computed tomographic (CT) venography. DS V demonstrated significant and immediate lack of opacification of the cervical IVVP at the site of compression. CT venography also demonstrated a similar lack of filling of the IVVP in areas of balloon compression. DSV images demonstrated the hemodynamic changes of the IVVP and their collateral veins during compression. During post-compression, DSV and CT venography images revealed that 5 dogs exhibited lack of filling of the cervical IVVP at the previously compressed area. Findings show that experimental spinal cord compression induces immediate local venous morphological alteration at the involved vertebral canal area. El plexo venoso vertebral interno (PVVI) es una red vascular localizada a lo largo del canal vertebral. El presente estudio fue dise ado para evaluar variaciones en la morfología del PVVI cervical bajo condiciones de compresión aguda de la médula espinal en perros. Una compresión medular experimental fue inducida en once perros adultos al nivel de C3/4 utilizando una técnica modificada de catéter de angioplastia con balón. Los perros fueron evaluados antes, durante y posterior a la compresión medular utilizando para ello venografia intraósea por substracción digital (VSD) y venografia por tomografía computarizada (TC). La VSD mostró pérdida manifiesta e inmediata de opacificación del PVVI cervical en el sitio de la compresión. La venografia por TC también evidenció pérdida de llenado del PVVI cervical con medio de contraste en las áreas comprimidas por el balón de angioplastia. La VSD también mostró cambios hemodinámicos del PVVI y sus ramas colaterales durante la compresión. Durante la postcompresión las imágenes de la VSD y la venografia por TC revelaron que algunos perros presentaban pérdida de llenado con medio de contraste del PVVI cervical en el área previamente comprimida. Los resultados de este estudio muestran que la compresión medular experimental en perros induce alteraciones locales inmediatas en la morfología venosa dentro del canal vertebral afectado.
Diagnosis of Deep Venous Thrombosis after Total Knee Arthroplasty: A Comparison of Ultrasound and Venography Studies.  [PDF]
Ching-Jen Wang,Chung-Cheng Huang,Pao-Chu Yu,Han-Hsiang Chen
Chang Gung Medical Journal , 2004,
Abstract: Background: A prospective clinical study was performed to compare the diagnostic accuracybetween ultrasound and venography of deep venous thrombosis (DVT)after total knee arthroplasty (TKA).Methods: This series consisted of 55 patients (43 women and 12 men) with an averageage of 61 (range, 51-81) years who underwent TKA. No pharmaceutical prophylaxisfor DVT was administered. Ultrasound and venographic studieswere performed to detect DVT within 5 to 7 days postoperatively.Results: The incidence of DVT was 36% (20 of 55) by clinical examination, 42% (23of 55) by ultrasound study, and 58% (32 of 55) with venography. The differencein number of cases of DVT determined between ultrasound and venographystudy was marginally significant statistically ( p = 0.082). When thevenographic results were used as the baseline reference, the sensitivity andspecificity of the ultrasound study in the diagnosis of DVT after TKA were87% and 63%, respectively.Conclusion: Ultrasound is a reasonably good alternative to venography in the diagnosis ofDVT after TKA. Ultrasound is non-invasive, safe, and convenient.Ultrasound can be used as the initial screening test for clinically suspectedDVT to be followed by venography in cases of equivocal results of the ultrasoundstudy and in patients with negative ultrasound results but clinicallyevident DVT.
Multi-detector computer tomography venography (MDCTV) as a diagnostic tool in the management of patients with atypical, complicated and/or recurrent varicose veins
A Lawson, P Rischbieter, J Owen, T Peedikayil, S Beningfield
South African Journal of Radiology , 2012,
Abstract: Aim. To evaluate the role of multi-detector computer tomography venography (MDCTV), compared with conventional venography, as a diagnostic tool in the management of patients with atypical, complicated and/or recurrent varicose veins. Materials and methods. Retrospective review of 21 patients who had undergone both MDCTV and conventional transfemoral or transpopliteal venography between January 2008 and April 2011 for the management of recurrent varicose veins and/or chronic venous ulcers. MDCTV was performed using a 16-slice CT scanner. Spiral acquisition was commenced 180 seconds after intravenous injection of 150 ml of 350 mmol/l iodinated contrast medium. A reconstruction interval of 1.5 mm was used. Conventional venography was performed by the resident vascular surgeon and was followed by stenting or coiling where appropriate. Results. MDCTV and venography were compared in 21 patients (6 male, 15 female; average age 55 years, range 33 - 78 years); 8 also underwent endovascular iliac vein stenting. The area under the receiver operator curve (ROC) for percentage iliac vein stenosis determined on MDCTV versus venography was 0.75. Four (19%) false-positive iliac vein stenoses were reported on MDCTV. Ten patients underwent gonadal vein coil embolisation. Gonadal vein size >5.2 mm (range 1 - 11 mm) on MDCTV predicted significant venographic reflux requiring coil embolisation. Three (30%) patients who underwent embolisation did not have gonadal vein enlargement on MDCTV. Conclusion. MDCTV plays an important adjunctive role in the diagnostic workup of patients with complex venous disease. The findings at MDCTV correlate well with conventional venography.
Characteristics of paraesophageal varices: A study with 64-row multidetector computed tomography portal venography  [cached]
Li-Qin Zhao, Wen He, Guang Chen
World Journal of Gastroenterology , 2008,
Abstract: AIM: To identify the characteristics of morphology, location and collateral circulation involved in paraesophageal varices (para-EV) of portal hypertension patients with 64-row multidetector computed tomography (MDCT).METHODS: Fifty-two of 501 patients with portal hypertensive cirrhosis accompanied with esophageal varices were selected for 64-row MDCT examination after the observation of para-EV. The CT protocol included unenhanced, arterial and portal phases with a slice thickness of 0.625 mm and a scanning field of 2 cm above the bifurcation to the lower edge of kidney. The CT portal venography (CTPV) was reformatted on AW4.3 workstation. The characteristics of origination, location, morphology and collateral circulation in para-EV were observed.RESULTS: Among the 52 cases of para-EV, 50 showed the originations from the posterior branch of left gastric vein, while the others from the anterior branch. Fifty cases demonstrated their locations close to the esophageal-gastric junction, and the other two cases were extended to the inferior bifurcation of the trachea. The circuitous pattern was observed in 16 cases, while reticulated pattern was seen in 36 cases. Collateral circulation identified 4 cases of single periesophageal varices (peri-EV) communication, 3 cases of single hemiazygous vein, one case of single inferior vena cava, 41 cases of mixed type (collateral communications of at least 2 of above mentioned types) and 3 cases of undetermined communications. Among all the cases, 43 patients showed the communications between para-EV and peri-EV, while hemiazygous vein (43 cases) and inferior vena cava (5 cases) were also involved.CONCLUSION: Sixty-four-row multidetector computed tomography portal venography could display the location, morphology, origin, and collateral types of para-EV, which provides important and referable information for clinical management and disease prognosis.
Normal Intracranial Venous Structures and Anatomical Variations on 3D Time-of-Flight MR Venography
Ali Hekmatnia,Amir Reza Radmard,Ehsan Yousefian,Farideh Naghshineh
Iranian Journal of Radiology , 2009,
Abstract: "nIntroduction: Accurate diagnosis of dural venous sinus thrombosis requires understanding of normal intracranial venous anatomy and its variants in the normal population. The purpose of this study is to evaluate various appearances of adult cerebral venous drainage depicted on three-dimensional (3D) time-of-flight (TOF) MR venography (MRV). "nMaterials and Methods: Two hundred and thirty one subjects (105 male, 126 female, aged 15- 89 years) with normal brain MR imaging, without compromise of cerebral venous outflow underwent 3D TOF MR venography using a 1.5 T unit. The visibility of cerebral veins and sinuses was determined by a single neuroradiologist. "nResults: The frequency of right, left and co-dominant transverse sinus were 83 (35.9%), 31 (13.4%) and 117 (50.6%), respectively. The mean age of co-dominant transverse sinus group (40.2±16.3 yrs.) was significantly lower than those with the absence of one transverse sinus (47.0±18.6 yrs.) (P=0.003). Subjects with right and left dominant transverse sinus did not show statistical age difference. Occipital sinus was visualized in 35 (15.2%) participants, of them 33 (94.2%) showed this sinus bilaterally. There was no significant age difference between participants with or without conspicuous occipital sinus. The vein of Galen, internal cerebral veins and basal veins of Rosenthal were evident in 201 (87.0%), 145 (62.8%) and 177 (76.6%) of the cases, respectively. All cases revealed patent superior sagittal sinus while 139 (60.2%) subjects showed inferior sagittal sinus patency. The straight sinus was obvious in all except 4 (1.7%) cases. "nConclusion: The present study may facilitate better understanding of intracranial venous structures which can minimize the probability of misdiagnosis in patients suspicious of dural venous sinus thrombosis. Absence of one transverse sinus seems to be a tendency.
Evaluation of the Optimal Image Reconstruction Interval for Noninvasive Coronary 64-Slice Computed Tomography Venography  [PDF]
Yasutoshi Ohta, Shinya Fujii, Suguru Kakite, Einosuke Mizuta, Masayuki Hashimoto, Toshio Kaminou, Toshihide Ogawa
Open Journal of Radiology (OJRad) , 2013, DOI: 10.4236/ojrad.2013.32010
Abstract:

Objective: We investigated the appropriate reconstruction interval required to generate optimal quality images of the coronary veins and to evaluate the size of each vein at the systolic and diastolic phases using coronary computed tomography (CT) venography. Methods: Coronary CT venograms obtained from 30 patients using 64-slice CT were reconstructed at 0% to 90% of the cardiac cycle in 10% increments. Two radiologists assessed the image quality of the anterior interventricular vein (AIV), the great cardiac vein (GCV), the posterior vein of the left ventricle (PVLV), the posterior interventricular vein (PIV), the coronary sinus (CS) and the small cardiac vein (SCV). We determined the sizes of measurable CS (n = 16) and GCV (n = 12) at the end systolic and mid diastolic phases. Results: The most appropriate reconstruction point for all coronary veins turned out to be at the mid-diastolic phase. The size of the CS and GCV was greater at a 30% than that at a 70% R-R interval (p < 0.01). Conclusions: Image quality was optimal at the mid-diastolic phase for each coronary vein, but the sizes of the coronary veins varied during the cardiac cycle. The cardiac cycle must be considered when measuring the sizes of cardiac veins.

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