Intracranial magnetic resonance venography in healthy individuals:normal anatomy and variations of the cerebral venous system

Objective:To evaluate the basic appearance and variation of the venous sinuses and veins in healthy individuals.Methods:Prospectively-recruited healthy volunteers completed a questionnaire and underwent magnetic resonance imaging plus contrast-enhanced magnetic resonance venography(CE-MRV)to measure their sinus diameters.Anatomical variations of cerebral venous sinuses were evaluated.Results:Fifty-eight individuals were included.The mean diameter of the left transverse sinus(LTS)(5.37±1.35 mm)was significantly smaller than that of the right transverse sinus(RTS)(6.65±1.57 mm)(P<0.001),and the average discrepancy was 19.2%.RTS dominance was noted in 55.1%of cases.Four superior sagittal sinus(SSS)anatomical variations were found.Type A was the most common and was present in 43 participants(74.1%).The SSS preferentially drained into the RTS in 32 patients(55.2%),and arachnoid granulation was observed in the transverse sinus(TS)and SSS in patients.According to our reclassification combined with Osborn’s previous research,we found that the SSS commonly drained into the RTS and that the straight sinus(StS)branched into both TSs.Conclusions:A 19%difference between the LTS and RTS provides a threshold for TS lateral dominance instead of a TS abnormality.Clinicians and radiologists should not ignore the influence of acquired pathology when the SSS drains in a non-RTS-dominant manner.Anatomical variations of the torcular herophili are frequent;the most commonly observed was the StS branching into both TSs,with the SSS draining into the RTS.

64-row multidetector computed tomography portal venography of gastric variceal collateral circulation

AIM:To study characteristics of collateral circulation of gastric varices (GVs) with 64-row multidetector computer tomography portal venography (MDCTPV).METHODS:64-row MDCTPV with a slice thickness of 0.625 mm and a scanning field from 2 cm above the tracheal bifurcation to the lower edge of the kidney was performed in 86 patients with GVS diagnosed by endoscopy. The computed tomography protocol included unenhanced,arterial and portal vein phases. The MDCTPV was performed on an AW4.3 workstation. GVs were classified into three types according to Sarin's Classification. The afferent and efferent veins of each type of GV were observed.RESULTS:The afferent venous drainage originated mostly from the left gastric vein alone (LGV) (28/86,32.59%),or the LGV more than the posterior gastric vein/short gastric vein [LGV > posterior gastric vein/short gastric vein (PGV/SGV)] (22/86,25.58%),as seen by MDCTPV. The most common efferent venousdrainage was via the azygos vein to the superior vena cava (53/86,61.63%),or via the gastric/splenorenal shunt (37/86,43.02%) or inferior phrenic vein (8/86,9.30%) to the inferior vena cava. In patients with gastroesophageal varices type 1,the afferent venous drainage of GV mainly originated from the LGV or LGV > PGV/SGV (43/48,89.58%),and the efferent venous drainage was mainly via the azygos vein to the super vena cava (43/48,89.58%),as well as via the gastric/splenorenal shunt (8/48,16.67%) or inferior phrenic vein (3/48,6.25%) to the inferior vena cava. In patients with gastroesophageal varices type 2,the afferent venous drainage of the GV mostly came from the PGV/SGV more than the LGV (PGV/SGV > LGV) (8/16,50%),and the efferent venous drainage was via the azygos vein (10/16,62.50%) and gastric/splenorenal shunt (9/16,56.25%). In patients with isolated gastric varices,the main afferent venous drainage was via the PGV/SGV alone (16/22,72.73%),and the efferent venous drainage was mainly via the gastric/splenorenal shunt (20/22,90.91%),as well as the inferior phrenic vein (3/23) to the inferior vena cava. CONCLUSION:MDCTPV can clearly display the afferent and efferent veins of all types of GV,and it could provide useful reference information for the clinical management of GV bleeding.

Characteristics of paraesophageal varices:A study with 64-row multidetector computed tomograghy portal venography

AIM:To identify the characteristics of morphology, loca- tion and collateral circulation involved in paraesophageal varices (para-EV) of portal hypertension patients with 64-row multidetector computed tomograghy (MDCT). METHODS: Fifty-two of 501 patients with portal hypertensive cirrhosis accompanied with esophageal varices were selected for 64-row MDCT examination af- ter the observation of para-EV. The CT protocol includ- ed 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 origina- tion, 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 esoph- ageal-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 identifi ed 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 communica-tions 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 tomograghy portal venography could display the loca- tion, morphology, origin, and collateral types of para- EV, which provides important and referable information for clinical management and disease prognosis.

Splanchnic vein thrombosis in necrotizing acute pancreatitis: Detection by computed tomographic venography

AIM: To assess the diagnostic accuracy of computed tomographic venography(CTV) for splanchnic vein thrombosis(SVT) detection in necrotizing acute pancreatitis(AP) patients.METHODS:Forty-three patients with necrotizing AP who underwent both CTV and digital subtraction angiography(DSA)within 3 d were analyzed in this retrospective comparative study.All CTV procedures were performed with a dual-source CT scanner.The presence and location of SVT were determined via blinded imaging data analyses.RESULTS:According to the DSA results,17(39.5%)of the total 43 patients had SVT.The sensitivity,specificity,positive and negative predictive values of CTV for SVT detection were 100%(95%CI:77.1%-100%),92.3%(95%CI:73.4%-98.7%),89.5%(95%CI:65.5%-98.2%)and 100%(95%CI:82.8%-100%),respectively.CONCLUSION:CTV is an effective examination for SVT detection in patients with necrotizing AP with high positive and negative predictive values.

Magnetic resonance venography and liver transplant complications

Hepatic vein stenosis is a rare but serious complication following liver transplantation.Multiple modalities can be utilized to image the hepatic vasculature.Magnetic resonance venography(MRV)provides certain advantages over ultrasound,computed tomography angiography and digital subtraction venography.MRV utilizes the same imaging principles of magnetic resonance angiography in order to image the venous system.Blood pool contrast agents,specifically gadofosveset trisodium,allow for steady state imaging up to 1 h following injection,with improved visualisation of vital venous structures by utilising delayed steady state imaging.Additionally,the inherent physics properties of magnetic resonance imaging also provide excellent soft tissue detail and thus help define the extent of complications that often plague the post-liver transplant patient.This case report describes the use of gadofosveset trisodium in a patient with hepatic venous stenosis following liver transplantation.Initial venography failed to outline the stenoses and thus MRV using a blood pool contrast agent was utilised in order to delineate the anatomy and plan a therapeutic endovascular procedure.

Antegrade pampiniform plexus venography in recurrent varicocele:Case report and anatomy review

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.

Intrahepatic portal venous systems in adult patients with cavernous transformation of portal vein: Imaging features and a new classification

Background: Cavernous transformation of the portal vein(CTPV) due to portal vein obstruction is a rare vascular anomaly defined as the formation of multiple collateral vessels in the hepatic hilum. This study aimed to investigate the imaging features of intrahepatic portal vein in adult patients with CTPV and establish the relationship between the manifestations of intrahepatic portal vein and the progression of CTPV. Methods: We retrospectively analyzed 14 CTPV patients in Beijing Tsinghua Changgung Hospital. All patients underwent both direct portal venography(DPV) and computed tomography angiography(CTA) to reveal the manifestations of the portal venous system. The vessels measured included the left portal vein(LPV), right portal vein(RPV), main portal vein(MPV) and the portal vein bifurcation(PVB). Results: Nine males and 5 females, with a median age of 40.5 years, were included in the study. No significant difference was found in the diameters of the LPV or RPV measured by DPV and CTA. The visualization in terms of LPV, RPV and PVB measured by DPV was higher than that by CTA. There was a significant association between LPV/RPV and PVB/MPV in term of visibility revealed with DPV( P = 0.01), while this association was not observed with CTA. According to the imaging features of the portal vein measured by DPV, CTPV was classified into three categories to facilitate the diagnosis and treatment. Conclusions: DPV was more accurate than CTA for revealing the course of the intrahepatic portal vein in patients with CTPV. The classification of CTPV, that originated from the imaging features of the portal vein revealed by DPV, may provide a new perspective for the diagnosis and treatment of CTPV.

Value of CT pulmonary arteriography and venography in the evaluation of venous thromboembolism in a multiracial Asian population

Background There is increasing evidence that CT pulmonary arteriography and venography allow a better diagnostic yield for deep vein thrombosis （DVT） in suspected acute pulmonary embolism （PE）. The aim was to investigate the value for using such an approach in a multiracial Asian population. Methods A total of 135 consecutive subjects with clinically suspected PE in various clinical settings （postoperative in 23 subjects） were referred and evaluated for venous thromboemboUsm using CT pulmonary arteriography and venography in a tertiary hospital, Malaysia. The distribution of DVT was assessed based on the frequency rate of thrombosis in a particular anatomical region （inferior vena cava, pelvic, femoral and popliteal）. Results In 130 subjects, excluding 5 subjects having poor images, both DVT and PE were detected in 11.5% （15/130） subjects and DVT alone was detected in 6.9% （9/130） subjects giving a combined rate of venous thromboembolism of 18.4%. A history of malignancy was significantly associated with positive scans, P=0.02. It was found that left pelvic veins （18.2%） and left femoral veins （19.5%） were more commonly thrombosed in this population. Conclusion CT pulmonary arteriography and venography is a useful technique in the evaluation of venous thromboembolism in a multi-racial Asian population.

Diagnostic performance of magnetic resonance venography in the detection of recanalization in patients with chronic cerebral venous sinus thrombus

Background In the chronic stage of cerebral venous sinus thrombosis （CVST）, recanalization can result in disparate MR appearances. We aimed to prospectively investigate the diagnostic accuracy of magnetic resonance venography （MRV） in the evaluation of the recanalization of CVST. Methods This study prospectively evaluated the diagnostic performance of 2-dimensional time-of-flight （2D-TOF） MRV in thirty-two consecutive patients during a threeto six-month follow-up for CVST. Both 2D-TOF MRV and digital substraction angiography （DSA） were undertaken. Diagnostic accuracy of 2D-TOF MRV in the detection of recanalized thrombus was evaluated using DSA as the reference standard. Results MRV and DSA were completed without complications in all 32 patients. The sensitivity, specificity, positive predictive value, and negative predictive value of 2D-TOF MRV for the detection of recanalization on a segmental basis were 91% （62/68）, 93% （37/40）, 95% （62/65）, and 86% （37/43） respectively. Conclusion 2D-TOF MRV provides high sensitivity and specificity for the diagnosis of recanalized CVST segments.

Review of imaging and endovascular intervention of iliocaval venous compression syndrome

Iliocaval venous compression syndrome(ICS)is the extrinsic compression of the common iliac vein by the overlying iliac artery against the vertebra.Chronic compression can lead to venous stenosis and stasis,which manifests as chronic venous disease and treatment resistance.Therefore,early recognition of ICS and prompt treatment are essential.Clinical presentations of ICS can be ambiguous and diagnosis requires a high index of suspicion with the relevant imaging studies.The initial imaging test is typically a Duplex ultrasound for vessel assessment and pelvic ultrasound to exclude a compressive mass,which is followed by computed tomography(CT)or magnetic resonance(MR)venography.CT and MRI can identify the anatomical causes for venous compression.In patients with high clinical suspicion for ICS,negative findings on CT and MR venography would still warrant further investigations.Definitive diagnosis can be established using catheter-based venography complemented with intravascular ultrasonography but the nature of their invasiveness limits its utility as a routine imaging modality.In this review paper,we will discuss the evidence,utility and limitations of the existing imaging modalities and endovascular intervention used in the management of ICS.

Budd-Chiari syndrome associated with liver cirrhosis: A case report

BACKGROUND Budd-Chiari syndrome(BCS)is a rare heterogeneous liver disease characterized by obstruction of the hepatic venous outflow tract.The incidence of BCS is so low that it is difficult to detect in general practice and difficult to include within the scope of routine diagnosis.The clinical manifestations of BCS are not specific;hence,BCS tends to be misdiagnosed.CASE SUMMARY We report the case of a 33-year-old Chinese woman who presented with progressive distension in the upper abdomen.She was initially misdiagnosed with liver cirrhosis(LC)due to abnormalities on an upper abdominal computed tomography scan.Although she was taking standard anti-cirrhosis therapy,her symptoms did not improve.Magnetic resonance imaging showed caudate lobe hypertrophy;and dilated lumbar and hemiazygos veins.Venography revealed membranous obstruction of the inferior vena cava owing to congenital vascular malformation.A definitive diagnosis of BCS was made.Balloon angioplasty was performed to recanalize the obstructed inferior vena cava and the patient’s symptoms were completely resolved.CONCLUSIONBCS lacks specific clinical features and can eventually lead to LC. Clinicians andradiologists must carefully differentiate BCS from LC. Correct diagnosis andtimely treatment are vital to the patient's health.

DIAGNOSIS AND TREATMENT OF IDIOPATHIC NECROSIS OF THE FEMORAL HEAD

Fifteen cases,27 hips,of idiopathic necrosis of the femoral head (INFH) were included iour series.The role of radiography,isotopic bone scanning,intraosseous pressure measure-ment and intraosseous venography in the diagnosis of INFH were evaluated.Radiologicalexamination could not reveal early cases,while isotopic bone scanning was more sensitive.There was an increase of intraosseous pressure in most of the diseased hips.and intraos-seous venography showed abnormalities in all examined hips.The latter two tests couldtherefore detect early INFH.Core decompression was performed in 23 hips,21 of whichwere followed for 7 to 27 months.Functional evaluation was good or excellent in 18 hips.Radiological re-examination remained unchanged in 19 hips.Postoperative intraosseouspressure measurement and intraosseous venography revealed a decrease of intraosseous pres-sure and improvement of venous drainage.Core decompression is therefore an ideal methodof treatment for early INFH.

Postpartum fatal cerebral vein thrombosis: A case report and review

Background: Cerebral vein thrombosis, is an emergent condition presenting with a variety of symptoms ranging from isolated headache to profound coma. Case Presentation: We present the case of a previously healthy young woman on the 18th postpartum day admitted into our hospital with a persistent headache for three days followed by seizures and coma. Magnetic Resonance Angiography revealed superior sagittal sinus and right transverse sinus thrombosis. Despite supportive measures and anticoagulation, the patient died because of uncontrolled increase in intracranial pressure. Conclusion: The possibility of cerebral vein thrombosis should be considered in all women with brain dysfunction during the puerperium.

Exceptional Association of a Cerebral Sinus Thrombosis and a Guillain-Barre Syndrome: A New Case Report and Review of the Literature

Background: The association of Guillain-Barre syndrome and cerebral sinus thrombosis is uncommon. Case Presentation: We report a 37-year-old patient hospitalized in medical ICU for respiratory distress following a Guillain-Barre syndrome. He had symptomatic treatment in addition to plasma exchange. In the presence of clonic movements, a brain venography magnetic resonance showed a thrombophlebitis of the left lateral sinus, and hence a low-molecular-weight heparin treatment was begun. Immunological, thrombophilia and serological tests were negative. After a favorable evolution, he was transferred to the neurology department. Conclusion: The combination of a Guillain-Barre syndrome and a cerebral sinus thrombosis would suggest a common process. A rigorous investigation, including the use of imaging, is necessary in front of any unusual clinical sign during a GBS.

Suspected Pulmonary Thromboembolism and Deep Venous Thrombosis： A Comprehensive 64-slice Multidetector Computed Tomography Diagnosis in Gynecologic Patients

Venous thromboembolism （VTE） is a systemic and potentially lethal illness. It consists of two related clinical manifestations： Pulmonary thromboembolism （PTE） and deep venous thrombosis （DVT）.It.21 DVT of the lower extremities is believed to be the source of PTE in most patients, and the primary risk factor for recurrent PTE is the presence of residual proximal venous thrombosis. Postoperative PTE is more difficult to diagnose compared with a spontaneous PTE because clinical symptoms and signs suggestive of PTE can be explained by the effects of operations,

Application of 3D Digital Reconstruction and Printing to the Diagnosis and Treatment of Iliac Vein Compression

The objective of this research was to explore the feasibility and clinical application of a new diagnostic imaging method for the diagnosis and treatment of iliac vein compression(IVC)based on three-dimensional(3D)digital reconstruction and printing.This study included patients with chronic venous disease(CVD)who were admitted to the Department of Vascular Surgery,Shanghai Ninth People’s Hospital,Shanghai Jiao Tong University School of Medicine,from January to March,2019,and underwent computed tomography venography(CTV)to detect IVC.CTV findings were used to reconstruct 3D-printed models of blood vessels.A total of 17 patients(5 men and 12 women)with IVC,who were primarily diagnosed with CTV,were included in this study.In addition,24 significant venous compression sites were found in 17 patients,of which 7 patients had only one compression site(41.2%),nine patients had two compression sites(52.9%),and one patient had three compression sites(5.9%).3D digital reconstruction and printing is a convenient,noninvasive,and accurate diagnostic imaging method that provides a clear and accurate evaluation of veins and arteries,as well as the anatomical positional relationship for the diagnosis and treatment of IVC.