Renal vein valves: a prevalence, microanatomical and histological study

PURPOSE

In the modern era of robotic renal procedures and diagnostics, an even more detailed anatomical understanding than hitherto is necessary. Valves of the renal veins (RVV) have been underemphasized and have been disputed by some authors, and few textbooks describe them. The current anatomical study was performed to address such shortcomings in the literature.

METHODS

One hundred renal veins were studied in fifty adult formalin-fixed cadavers. Renal veins were removed from the abdomen after sectioning them flush with their entrance to the renal hilum. The inferior vena cava was then incised longitudinally and opened, and RVV were examined grossly and histologically. A classification scheme was developed and applied to our findings.

RESULTS

Nineteen RVVs were observed in the fifty cadavers (38%). Four (8%) valves were found on right sides and fifteen (30%) on left sides. The valves were seen as cord/band-like, folds, and single and double leaflets. Histologically, they were all extensions of the tunica intima.

CONCLUSION

On the basis of our study, RVV are not uncommon. They were more common on left sides, and on both sides, they were found within approximately one centimeter of the junction of the inferior vena cava and renal vein. Although the function of such valves cannot be inferred from this anatomical study, the structures of the Single leaflet valve (TS2) and Double leaflet valve (TS3) valves suggest they could prevent venous reflux from the IVC into the kidney.

An unusual case of duplicated left brachiocephalic vein with right sided aortic arch and aberrant origin of LSCA in a patient undergoing implantable cardioverter defibrillator (ICD) implantation

BACKGROUND

Anomalous left brachiocephalic vein (ALBCV) is a rare venous anomaly. Double Left brachiocephalic vein is the rarest type of ALBCV anomaly.

CASE REPORT

Here we report a case of gentleman with post myocardial infarction ventricular tachycardia who underwent ICD implantation, where we could not place the lead initially through left side. CT angiography revealed presence of a duplicated circumaortic left BCV. It's cranial limb coursing normally anterior to arch and compressed at its confluence with RBCV and the caudal limb with a subaortic course draining into the RSVC. We report this first case of double LBCV along with right sided aortic arch and aberrant origin of LSCA arising from Kommerel's diverticulum.

CONCLUSION

This case highlights that interventional cardiologists should be aware of these venous anomalies for proper planning and implantation of CIED successfully via transvenous approach.

Diffuse generalized venulitis as the primary pathology of Behçet's disease: A comprehensive magnetic resonance venography study

OBJECTIVE

Behçet's Disease (BD) is a chronic multisystem vasculitis that manifests with destructive inflammation affecting the eyes, central nervous system, and blood vessels. The pathology of vein involvement in BD is poorly characterized. Magnetic resonance (MR) venography gives more comprehensive information about deep veins and adjacent tissues. In this study, we aimed to characterize vein involvement and evaluate the diagnostic utility of MR venography in BD.

METHODS

Sixty-five BD patients who fulfilled the International Study Group (ISG) criteria and 20 healthy control subjects were enrolled. Inferior vena cava (IVC), common iliac veins (CIV), external (EIV) and internal iliac veins (IVV), common femoral veins (CFV), femoral veins (FV), and greater saphenous veins (GSV) of BD patients and healthy controls were evaluated with MR venography and ultrasonography for the presence pathologic features, luminal thrombi, vessel wall changes, and perivascular abnormalities.

RESULTS

33 vascular and 32 non-vascular BD patients (mean age 39.3 ± 11.3 years and 48 [73.8%] male) were enrolled. MR venography revealed diffuse concentric thickening of the walls of IVC, CIV, EIV, IIV, CFV, FV, and GSV in BD (healthy controls vs. BD p<0.05 for all vein segments). MR venography provided additional information about veins and perivascular tissues like contrast enhancement, enlarged lymph nodes, and seminal vesicle vascularization, which were remarkably more frequent in vascular BD than non-vascular BD and healthy controls.

CONCLUSION

The results of our study suggest that the involvement of the venous system is diffuse and generalized in BD, and demonstration of venulitis might help diagnose the disease.

Ferumoxytol-enhanced MR venography for diagnosis of venous thoracic outlet syndrome

Venous thoracic outlet syndrome commonly results in arm swelling and pain as the subclavian vein is obstructed within the thoracic inlet. We report the use of ferumoxytol-enhanced contrast MRI in the diagnosis of venous thoracic outlet syndrome in a male adolescent. In this patient who presented with right upper extremity thrombosis, ferumoxytol-enhanced MRI of the chest was able to show both chronic subclavian vein thromboses and dynamic occlusion of the subclavian veins with arm abduction consistent with Paget-Schroetter syndrome.

Imaging Approach to Venous Sinus Thrombosis

Cerebral venous thrombosis (CVT) is a rare cerebrovascular disease caused by an occlusion of the cerebral venous sinuses or cortical veins. It has a favorable prognosis if diagnosed and treated early. CVT can be difficult to diagnose on clinical grounds, and imaging plays a key role. We discuss clinical features and provide an overview of current neuroimaging methods and findings in CTV.

Risk factors for the development of secondary intracranial hypertension in acute cerebral venous thrombosis

PURPOSE

Intracranial hypertension (IH) can complicate cerebral venous thrombosis (CVT), potentially causing permanent visual loss. Current knowledge on risk factors for the development of IH following CVT is scarce. We applied a compound classifier (CSF opening pressure > 25 cmH₂O, papilledema, or optic disc protrusion on MRI) as a surrogate for IH and studied the predictive value of thrombus location, the number of thrombosed segments, and thrombus volume.

METHODS

We prospectively included 26 patients with acute CVT and complete MRI data. IH was defined by CSF opening pressure > 25 cmH₂O, papilledema, or optic disc protrusion on MRI. Using high-resolution contrast-enhanced venography, we determined the thrombus location, number of thrombosed segments, and thrombus volume. We analyzed their association with IH by logistic regression, their predictive power by the area under the receiver operating characteristic curve, and their association with CSF opening pressure by linear regression.

RESULTS

IH occurred in 46% of CVT patients and was associated with higher thrombus volume (AUC 0.759, p = 0.025) and superior sagittal sinus thrombosis both alone (OR 2.086, p = 0.049) and combined with transverse sinus thrombosis (OR 2.014, p = 0.028). Effects in patients presenting CSF opening pressure > 25 cm H₂O and the compound classifier were consistent. Thrombus volume > 4 ml was the single most important predictor of higher CSF opening pressure (ß = 0.566, p = 0.035), increasing IH risk.

CONCLUSION

Larger thrombus volume, dominant transverse sinus occlusion, and extensive superior sagittal combined with transverse sinus thrombosis were associated with IH. Thrombus volumetry might identify patients at risk for IH and direct further clinical evaluation.

Unsubtracted Roadmap Technique for Preventing Cement Leakage During Percutaneous Vertebroplasty: A Retrospective Cohort Study

OBJECTIVE

To determine the effectiveness of the unsubtracted roadmap technique (USRT) for decreasing cement leakage (CL) during percutaneous vertebroplasty (PVP).

METHODS

In this retrospective cohort study, patients who underwent PVP between January and November 2018 were included. Patients were divided into the unsubtracted roadmap (UR) (n = 20) and conventional venography (CV) (n = 22) groups. USRT was performed before cement injection in the UR group. Computed tomography was performed on the first day after PVP in both groups to assess the CL. The vertebral height restoration rate was confirmed by radiography before and after the procedure. The CL location was classified as basivertebral vein (type B), segmental vein (type S), or cortical defect (type C). Visual analog scale and Oswestry Disability Index scores before and after surgery were calculated to confirm clinical outcomes.

RESULTS

Based on the computed tomography images, CL occurred in 7 (34.78%) and 15 (63.64%) cases in the UR and CV groups, respectively. Number of CL type B, S, and C in the UR and CV groups were 2 and 6, 3 and 6, and 2 and 3, respectively. The injected cement volume was not significantly different between the UR (4.86 mL) and the CV (4.75 mL) groups (P = 0.450). Regarding vertebral body height restoration (P = 0.856) and clinical outcomes, there were no significant differences between both groups. Radiation exposure was significantly less in the UR group (P = 0.019).

CONCLUSIONS

USRT is an effective method for reducing CL and radiation exposure during PVP.

Novel therapy for recanalization of chronic iliocaval venous occlusion using radiofrequency

OBJECTIVE

Chronic venous disease of the lower extremities is one of the most common diseases in the United States. The sequelae of this disease process are the source of a significant amount of morbidity, and its prevalence is expected to increase in the coming decades. Interventional therapy is warranted for relief of patients with CEAP C3-C6 disease. With advances in endovascular therapy, chronic iliocaval venous occlusion (CICVO) pathology can be corrected through minimally invasive approaches with limited morbidity and mortality. However, failure to recanalize the venous system leads to high failure rates. The purpose of this study was to assess the procedural success for recanalization of CICVO in the community setting using the novel technique of the Baylis radiofrequency (RF) wire in patients who had failed previous endovascular intervention.

METHODS

A retrospective review of patients who underwent RF recanalization for CICVO at our institution from 2019 to 2020 was conducted. All patients had failed previous endovascular attempts at recanalization. The primary outcome was recanalization (defined as restoration of >70% of luminal patency as determined on multiplanar venography [MPV] and intravascular ultrasound [IVUS]) confirmed on both IVUS and MPV. Secondary outcomes included adjunctive interventions and complications (hematoma, pulmonary embolism, new onset renal insufficiency).

RESULTS

A total of 10 patients, 50% male with a mean (standard deviation) age of 58.4 (10.4), were evaluated in the study. Successful recanalization was achieved in 60% of cases, with a resolution of >70% of luminal obstruction observed using MPV and IVUS. Adjunctive interventions were performed in 70% of cases. There were no clinically significant complications or blood transfusion requirements.

CONCLUSIONS

New techniques and technologies continue to be developed for advanced endovascular management of CICVO, especially with the expanding market for Food and Drug Administration approved venous stents. The Baylis RF wire can assist in recanalization and treatment of patients who had failed previous endovascular therapy.

Intravascular ultrasound evaluation during iliofemoral venous stenting is associated with improved midterm patency outcomes

OBJECTIVE

Intravascular ultrasound (IVUS) examination is increasingly used in the treatment of iliofemoral venous disease and provides more sensitive and specific detection of stenotic lesions when compared with traditional multiplanar venography alone. Correlations with deep venous stent patency, however, have not yet been investigated. The objective of the study was to evaluate the impact of the use of IVUS examination in addition to multiplanar venography on iliofemoral venous patency.

METHODS

Consecutive patients who underwent stenting for symptomatic thrombotic or nonthrombotic iliofemoral venous lesions (NIVLs) between 2014 and 2020 at a single institution were identified and divided into two groups based on whether IVUS examination was used before stent deployment in addition to multiplanar venography compared with venography alone. A retrospective review of demographic, operative, and follow-up data was performed. Thirty-day and 2-year stent patency were measured as primary end points. χ² analysis, logistic regression models, and Kaplan-Meier survival analysis were used to determine outcomes. Technical details and outcomes were additionally examined among patients treated for acute deep venous thrombosis, post-thrombotic syndrome, or NIVLs separately on subgroup analysis.

RESULTS

We identified 150 patients (173 limbs, 23 bilateral) who underwent iliofemoral stenting during the study period at our institution (mean age: 48.8 ± 16.8 years, 61% female). Adjunctive IVUS utilization before stent deployment was reported in 69 of 173 (39.9%) treated limbs. IVUS examination was more likely to be used in patients who underwent stenting for NIVLs compared with thrombotic disease (41.0% vs 11.2%, P < .01). There was no difference in the number of stents deployed between IVUS and non-IVUS cohorts. However, IVUS examination was associated with the increased total length of the stent deployed (126 ± 56 vs 112 ± 48 mm, P = .04) and a higher rate of infrainguinal stent extension (17.4% vs 6.7%, P = .03). In addition, mean stent diameter was significantly higher when IVUS examination was performed before stent placement (16.3 ± 3.7 vs 15.2 ± 1.9 mm, P < .01). Both 30-day (98.5% vs 89.4%, P = .02) and 2-year (90.3% vs 78.7%, P = .03) primary patency were significantly higher in the IVUS cohort. Adjunctive IVUS use was found to significantly protect against stent reintervention at 2 years on adjusted Cox regression analysis (hazard ratio: 0.22, 95% confidence interval: 0.07-0.71, P = .01).

CONCLUSIONS

Adjunctive IVUS utilization is associated with differences in stent diameter and length selections as well as landing segments in the treatment of thrombotic and nonthrombotic iliofemoral venous disease. IVUS examination before stent deployment significantly protects against 30-day and 2-year stent reintervention when compared with the use of multiplanar venography alone. These data provide stronger evidence for routine IVUS use in addition to venography before iliofemoral venous stenting.

Routine use of concurrent fluoroscopic imaging during superficial endovenous interventions: A position statement of the International Union of Phlebology, the Australasian College of Phlebology, the Australia and New Zealand Society for Vascular Surgery, the American Venous Forum, the American Vein and Lymphatic Society, the European College of Phlebology and the Interventional Radiology Society of Australasia

International evidence-based guidelines recommend preoperative duplex ultrasound mapping in the assessment of chronic venous disease, and concurrent ultrasound imaging to guide superficial endovenous interventions such as endovenous laser ablation, radiofrequency ablation, cyanoacrylate adhesive closure, and sclerotherapy (ultrasound-guided sclerotherapy). Other imaging modalities such as venography, alone or in combination with computed tomography scan or magnetic resonance imaging, may be included in the preoperative assessment of a small and select group of patients to exclude central venous obstruction, certain deep venous pathologies, pelvic origin extrapelvic varices, and complex vascular malformations. The signatory scientific and medical societies recommend against the routine use of fluoroscopy and other radiation-based imaging in the investigation and treatment of superficial venous disease.

Imaging to intervention: Thoracic outlet syndrome

Thoracic outlet syndrome (TOS) is a clinical disorder resulting from compression of the neurovascular bundle of the lower neck and upper chest. TOS can be categorized into neurogenic, venous, and arterial subtypes which result from anatomical compression of the brachial plexus, subclavian vein, and subclavian artery, respectively. This can lead to neurogenic pain as well as vascular injury with thrombosis and thromboembolism. Interventional and diagnostic radiologists play a critical role in the imaging diagnosis and treatment of vascular TOS. Prompt imaging and endovascular management with surgical collaboration has been shown to provide the most successful and long-lasting clinical outcomes, from vessel patency to symptom relief. In this article, we review the anatomy and clinical presentations of TOS as well as the initial imaging modalities used for diagnosis. Furthermore, we detail the role of the diagnostic and interventional radiologist in the management of TOS, including pre-procedure and endovascular interventions, along with medical and surgical treatments. PRECIS: Diagnostic and Interventional Radiologists play a key role in diagnosis and management of vascular thoracic outlet syndromes and are critical for timely and successful outcomes.

Contrast-enhanced body magnetic resonance angiography: how we do it

This review introduces the basic principles of contrast-enhanced magnetic resonance (MR) angiography and details four contrast-enhanced MR angiography sequences for body imaging with extracellular gadolinium-based contrast agents in pediatric patients. Specifically, this review covers (1) respiratory-navigated, cardiac-gated MR angiography; (2) time-resolved MR angiography; (3) conventional MR angiography; and (4) modified spoiled gradient echo variants. We present and discuss indications, technical considerations, sequence optimization, advantages and disadvantages, along with practical tips and illustrative case examples for each sequence.

Indirect CT venography of the lower extremities: impact of scan delay and patient factors on contrast enhancement and examination quality

OBJECTIVES

Indirect computed tomography venography (CTV) is often the next imaging modality for deep vein thrombosis (DVT) when sonography is inconclusive. Our aim was to investigate the impact of scan delay and patient factors on contrast enhancement (CE) and examination quality in CTV.

METHODS

Patients with clinical suspicion or clinical mimics of DVT in one large hospital were enrolled. Age, sex, body weight, height, heart rate, systolic blood pressure and cardiac output were registered. CTV of the popliteal veins was obtained at 30 s intervals at 30-210 s delays. The proportions of examinations with CE exceeding predefined cut-offs were estimated and subjective examination quality was rated. Changes in CE with time, and associations between patient factors and time to peak contrast enhancement (TPCE) were modelled with mixed effects non-linear and linear regression, respectively.

RESULTS

The CE increased with increasing scan delay and reached a plateau from 120 to 210 s. The percentages of examinations achieving enhancement above cut-offs across all thresholds from 70 to 100 HU were higher at 120 s compared to 90 s (p < 0.001). After 120 s, there were no differences across scan delays for any thresholds. No patient factors showed a significant effect on TPCE. The percentage of examinations rated as acceptable was higher at 120 s compared to 90 s (p < 0.001). After 120 s, there were no statistically significant differences across scan delays.

CONCLUSIONS

No patient factors were associated with TPCE in CTV. A fixed scan delay of 120-210 s yielded the best examination quality.

KEY POINTS

• Contrast enhancement reached a plateau at scan delay between 90 and 120 s. • A scan delay of 120-210 s yielded the best examination quality. • No patient factors were associated with time to peak contrast enhancement.

Successful ligation of posterior tibial vein aneurysm performed according to intraoperative venography results

A 23-year-old woman was diagnosed with a posterior tibial vein aneurysm that had resulted in deep vein thrombosis and a pulmonary embolism. The patient responded well to anticoagulation therapy, and surgical resection was planned to prevent recurrence. She was scheduled to undergo tangential aneurysmectomy and lateral venorrhaphy. However, the aneurysm could not be completely exposed because of adhesions. Therefore, venography was performed to identify the inflow and outflow vessels, which were ligated because an accessory venous communication was identified. Intraoperative venography can aid in the selection of simple ligation or reconstruction of a venous communication for the treatment of posterior tibial vein aneurysms.

Real-time venography-guided extrathoracic puncture technique for cardiovascular implantable electronic device implantation

Central venous access is an essential technique for cardiovascular implantable electronic device (CIED) implantation, and the use of axillary vein approach has recently been increasing. This study sought to examine whether real-time venography-guided extrathoracic puncture facilitates the procedure. We retrospectively analyzed 179 consecutive patients who underwent CIED implantation using the axillary vein puncture method. Patients were divided into two groups: the conventional method group (CG, n = 107) and the real-time venography-guided group (RG, n = 82). The application of real-time venography was at the discretion of individual operators. Operators with experience of less than 50 CIED implantations were defined as inexperienced operators in this study. Puncture duration and number of attempts were significantly less in the RG group than in the CG group (283 ± 198 vs. 421 ± 361 s, p < 0.01, and 3.19 ± 2.00 vs. 4.18 ± 2.85, p < 0.01). These benefits of real-time venography were observed in inexperienced operators, but not in experienced operators. In addition, the success rate without extra attempts at puncture was higher in the RG group (54% vs. 32%, p < 0.01). Although the total amount of contrast medium was higher in the RG group (16.3 ± 4.1 mL vs. 11.9 ± 6.6 mL, p < 0.01), serum levels of creatinine pre- and post-operation were not different in the two groups (p = NS). We concluded that real-time venography is a safe and effective method for axillary vein puncture, especially in inexperienced operators.

Comparison of Simultaneous Bilateral Internal Carotid Artery (ICA) 3-Dimensional Rotational Venography (3D-RV) versus Separate Bilateral ICA 3D-RV and Postprocessing 3D-3D Fusion

BACKGROUND

Preoperative venogram of the superior sagittal sinus (SSS) is helpful to plan the surgical resection strategy in patients with parasagittal meningiomas invading the SSS.

METHODS

Catheter 3-dimensional rotational venography (3D-RV) allows for SSS patency assessment and detection of alternative venous cortical drainage routes in patients with contraindication for magnet resonance venography. It is unknown if separate bilateral internal carotid artery 3D-RV followed by postprocessing 3D-3D fusion (technique 1) achieves the same imaging results as simultaneous bilateral internal carotid artery 3D-RV without postprocessing fusion (technique 2) needed.

RESULTS

In this report we were able to confirm in 2 patients that both techniques achieve comparable imaging quality with similar amount of contrast use.

CONCLUSIONS

Although technique 2 requires less radiation, technique 1 is favored due to the need for only 1 vessel access site and catheter with reduced risk for access site and ischemic complications.

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.

CONCLUSION

BCS lacks specific clinical features and can eventually lead to LC. Clinicians and radiologists must carefully differentiate BCS from LC. Correct diagnosis and timely treatment are vital to the patient's health.

Evaluation and Management of Venous Thoracic Outlet Syndrome

Venous thoracic outlet syndrome (TOS) is uncommon but occurs in young, healthy patients, typically presenting as subclavian vein (SCV) effort thrombosis. Venous TOS arises through chronic repetitive compression injury of the SCV in the costoclavicular space with progressive venous scarring, focal stenosis, and eventual thrombosis. Diagnosis is evident on clinical presentation with sudden spontaneous upper extremity swelling and cyanotic discoloration. Initial treatment includes anticoagulation, venography, and pharmacomechanical thrombolysis. Surgical management using paraclavicular decompression can result in relief from arm swelling, freedom from long-term anticoagulation, and a return to unrestricted upper extremity activity in more than 90% of patients.

Intravenous Regional Limb Perfusion in Standing and Recumbent Horses: A Comparative Radiographic Study

Although pharmacokinetic studies of drugs administered by intravenous regional limb perfusion (IRLP) to treat equine orthopedic infections suggest efficient drug distribution in the limbs, it remains unclear whether drug perfusion is affected by the position of the horse during the procedure. This study compared the perfusion of a radiopaque contrast into tissues of the extremities of horses maintained in standing and recumbent positions during an IRLP. Radiopaque contrast was administered through IRLP into the cephalic vein of 10 healthy adult horses under general anesthesia and right lateral recumbency (RG) or under sedation and standing (SG). The same animals were used in both groups, respecting a two-week washout period. Sequential radiographic images were performed immediately at the beginning of contrast administration (T0) and after 10, 20, 30, 40, and 50 minutes. Tourniquets were removed after 30 minutes. The time required for the contrast to reach the hooves was compared between groups. Contrast reached the hooves faster in SG (114 ± 15 seconds) compared with RG (236 ± 29 seconds) (P < 0.5). SG showed more uniform perfusion of the limb vessels, whereas RG showed more deposition of the contrast in the lateral digital vein, with smaller amounts reaching the hooves. From T10 onward, soft tissue radiopacity increased, albeit more markedly in standing than in recumbent animals, remaining until T50. Contrast radiography evidenced that IRLP performed in standing position leads to a quicker and more uniform perfusion of the vasculature and a more noticeable diffusion to the tissues than in recumbent horses.

Neurovascular venous anatomy: Brain, head, and neck

The venous anatomy of the brain, head, and neck is essential to endovascular diagnosis and therapy. This chapter provides an overview of the venous system.

Gelfoam with Venography

Objective

Percutaneous vertebroplasty (VP) has been used for the safe treatment of osteoporotic compression fracture. However, cement leakage is the most common complication. To reduce the leakage of bone cement, we did the gelfoam embolization during VP. The purpose of this study is to compare the safety and feasibility of different two gelfoam embolization technique during VP.

Methods

Total 127 patients (146 level) who had the thoracolumbar osteoporotic compression fracture were enrolled. Group A was treated by gelfoam-only technique and, Group B was treated by gelfoam with venography technique. We compared the incidence of bone cement leakage between two groups using post-operative computed tomography scan and X-ray.

Results

Seventy-four patients (81 levels) were treated with gelfoam-only technique (A), and 53 patients (65 levels) were treated with gelfoam with venography technique (B). There were 22 leakages on group A, and 19 leakages on group B. There was no statistical significant difference between two groups (Chi-square test, p-value =0.958). Incidence of leakage to spinal canal was 11 levels in Group A, 3 levels in group B, and there was statistical significant difference (Fisher's exact test, p-value=0.027).

Conclusion

Complication induced by the bone cement leakage are the most careful point during VP. Gelfoam embolization with venography is very easy and safe method. Gelfoam with venography technique could make lower the incidence of cement leakage to spinal canal.

Clinical and imaging features in fibro-adipose vascular anomaly (FAVA)

BACKGROUND

Fibro-adipose vascular anomaly (FAVA) is a rare and recently described complex vascular malformation. The clinical and imaging features and morphology can be confusing and often overlap with features of other vascular malformations and tumors.

OBJECTIVE

To present the imaging characterization of FAVA in association with clinical features.

MATERIALS AND METHODS

We retrospectively evaluated clinical and imaging (MRI, sonography and venography) findings in FAVA. We documented the clinical presentation, lesion morphology, imaging characteristics, tissue distribution, pattern of contrast enhancement and vascular characteristics.

RESULTS

Thirty-eight people (31 female, 7 male) ages 1-30 years (mean 12 years) were diagnosed with FAVA based on clinical findings combined with imaging or histopathological findings (n=17). Most lesions were in the lower extremity (n=36). Three patterns were noticed: focal, focal infiltrative and diffuse.

CONCLUSION

Fibro-adipose vascular anomaly, a rare and complex vascular malformation, has distinct clinical and imaging features that a radiologist should be familiar with to avoid delay in diagnosis and to direct appropriate management.

Evaluation of venous pathology of the lower extremities with triggered angiography non-contrast-enhanced magnetic resonance imaging

Background

To explore the diagnostic performance of triggered angiography non-contrast-enhanced magnetic resonance imaging (TRANCE-MRI) for the evaluation of venous pathology of the lower extremity.

Methods

This was a single-centre prospective cohort study of 25 patients with suspected venous disease in the lower extremities. Each patient received Doppler ultrasonography (for venous evaluation) before the scheduled TRANCE-MRI (for venous and arterial evaluations) on a 1.5 T MR scanner (Philips Ingenia, Philips Healthcare, Best, the Netherlands), followed by lymphography and computed tomography angiography that were arranged according to the diagnostic indications.

Results

The sensitivity, specificity and accuracy of TRANCE-MRI were 85.7%, 88/9 and 88%, respectively. The inter-rater agreement for deep vein thrombosis (DVT) of the thigh between the ultrasonography and TRANCE-MRI results was substantial agreement (Cohen’s kappa κ, 0.72). In ultrasonography-negative cases, TRANCE-MRI detected four additional cases (16%, 4/25) of DVT; three cases (12%, 3/25) of venous compression caused by pelvic lymphadenopathy, hip prosthesis or knee joint effusion; one case (4%, 1/25) of vena cava anomaly; two cases (8%, 2/25) of occult peripheral artery disease (PAD); and one case (4%, 1/25) of an occluded bypass graft.

Conclusion

TRANCE-MRI can be used as an alternative and objective tool for assessing lower extremity diseases, especially suspected venous pathology. Compared with ultrasonography, TRANCE-MRI plays a better role in assessing varicose veins of the lower extremities and deep veins of the pelvis and abdomen. However, false-positive results may occur in the left common iliac vein of elderly patients. Finally, occult PAD rarely occurs in patients with suspected lower extremity venous disease. Therefore, we recommend performing the TRANCE-MRV protocol instead of the full protocol (MRV + MRA) in the clinical setting in patients with venous scenarios.

How to Implant Cardiac Resynchronization Therapy in a Busy Clinical Practice

Implantation of cardiac resynchronization therapy devices represents one of the more challenging and time-consuming procedures for the clinical electrophysiologist. This article reviews several strategies used to improve efficiency, safety, and effectiveness of cardiac resynchronization therapy implantation. The cornerstone of our strategy to improve efficiency, safety, and quality of cardiac resynchronization therapy implantation is the use of a telescoping guide system with high-quality venography. Competency in subclavian venoplasty and snaring techniques are essential to maintain efficiency and effectiveness during difficult cases.

A robust multi-scale approach to quantitative susceptibility mapping

Quantitative Susceptibility Mapping (QSM), best known as a surrogate for tissue iron content, is becoming a highly relevant MRI contrast for monitoring cellular and vascular status in aging, addiction, traumatic brain injury and, in general, a wide range of neurological disorders. In this study we present a new Bayesian QSM algorithm, named Multi-Scale Dipole Inversion (MSDI), which builds on the nonlinear Morphology-Enabled Dipole Inversion (nMEDI) framework, incorporating three additional features: (i) improved implementation of Laplace's equation to reduce the influence of background fields through variable harmonic filtering and subsequent deconvolution, (ii) improved error control through dynamic phase-reliability compensation across spatial scales, and (iii) scalewise use of the morphological prior. More generally, this new pre-conditioned QSM formalism aims to reduce the impact of dipole-incompatible fields and measurement errors such as flow effects, poor signal-to-noise ratio or other data inconsistencies that can lead to streaking and shadowing artefacts. In terms of performance, MSDI is the first algorithm to rank in the top-10 for all metrics evaluated in the 2016 QSM Reconstruction Challenge. It also demonstrated lower variance than nMEDI and more stable behaviour in scan-rescan reproducibility experiments for different MRI acquisitions at 3 and 7 Tesla. In the present work, we also explored new forms of susceptibility MRI contrast making explicit use of the differential information across spatial scales. Specifically, we show MSDI-derived examples of: (i) enhanced anatomical detail with susceptibility inversions from short-range dipole fields (hereby referred to as High-Pass Susceptibility Mapping or HPSM), (ii) high specificity to venous-blood susceptibilities for highly regularised HPSM (making a case for MSDI-based Venography or VenoMSDI), (iii) improved tissue specificity (and possibly statistical conditioning) for Macroscopic-Vessel Suppressed Susceptibility Mapping (MVSSM), and (iv) high spatial specificity and definition for HPSM-based Susceptibility-Weighted Imaging (HPSM-SWI) and related intensity projections.

Cardiovascular magnetic resonance black-blood thrombus imaging for the diagnosis of acute deep vein thrombosis at 1.5 Tesla

BACKGROUND

The aim was to investigate the feasibility of a cardiovascular magnetic resonance (CMR) black-blood thrombus imaging (BBTI) technique, based on delay alternating with nutation for tailored excitation black-blood preparation and a variable flip angle turbo-spin-echo readout, for the diagnosis of acute deep vein thrombosis (DVT) at 1.5 T.

METHODS

BBTI was conducted in 15 healthy subjects and 30 acute DVT patients. Contrast-enhanced CMR venography (CE-CMRV) was conducted for comparison and only performed in the patients. Apparent contrast-to-noise ratios between the thrombus and the muscle/lumen were calculated to determine whether BBTI could provide an adequate thrombus signal for diagnosis. Two blinded readers assessed the randomized BBTI images from all participants and made independent decisions on the presence or absence of thrombus at the segment level. Images obtained by CE-CMRV were also randomized and assessed by the two readers. Using the consensus CE-CMRV as a reference, the sensitivity, specificity, positive and negative predictive values, and accuracy of BBTI, as well as its diagnostic agreement with CE-CMRV, were calculated. Additionally, diagnostic confidence and interobserver diagnostic agreement were evaluated.

RESULTS

The thrombi in the acute phase exhibited iso- or hyperintense signals on the BBTI images. All the healthy subjects were correctly identified from the participants based on the segment level. The diagnostic confidence of BBTI was comparable to that of CE-CMRV (3.69 ± 0.52 vs. 3.70 ± 0.47). High overall sensitivity (95.2%), SP (98.6%), positive predictive value (96.0%), negative predictive value (98.3%), and accuracy (97.7%), as well as excellent diagnostic and interobserver agreements, were achieved using BBTI.

CONCLUSION

BBTI is a reliable, contrast-free technique for the diagnosis of acute DVT at 1.5 T.

Magnetic Resonance Venography Findings of Obstructed Hepatic Veins and the Inferior Vena Cava in Patients with Budd-Chiari Syndrome

Objective

This study aimed to illustrate the magnetic resonance venography (MRV) manifestations of obstructed hepatic veins (HVs), the inferior vena cava (IVC), and accessory hepatic veins (AHVs) in patients with Budd-Chiari syndrome (BCS) and to evaluate the visualization capacity of MRV in the diagnosis of BCS.

Materials and Methods

Fifty-two patients with chronic BCS were included in this study. All patients were examined via MRV performed with a 3T system following injections of gadolinium-diethylene triamine pentaacetic acid (Gd-DTPA) or Gd-ethoxibenzyl-DTPA. HV and IVC lesions were classified, and their characteristics were described. HV cord-like occlusions detected via MRV were compared using ultrasonography (US). Digital subtraction angiography (DSA) was performed as a contrast in the MRV detection of IVC lesions. The HVs draining collaterals, mainly AHVs, were carefully observed. HV lesions were classified as segmental stenosis, segmental occlusion, membranous stenosis, membranous occlusion, cord-like occlusion, or non-visualized. Except for patent IVCs, IVC lesions were classified as segmental occlusion, segmental stenosis, membranous occlusion, membranous stenosis, and hepatomegaly-induced stenosis.

Results

All patients (52/52, 100%) showed HV lesions of different degrees. MRV was inferior to US in detecting cord-like occlusions (6 vs. 19, χ² = 11.077, p < 0.001). Dilated AHVs, including 50 (50/52, 96.2%) caudate lobe veins and 37 (37/52, 71.2%) inferior HV and AHV lesions, were well-detected. There were no significant differences in detecting segmental lesions and thrombosis between MRV and DSA (χ² = 0.000, p1 = 1.000, p2 = 1.000). The capacity of MRV to detect membranous lesions was inferior to that of DSA (7 vs. 15, χ² = 6.125, p = 0.013).

Conclusion

In patients with BCS, MRV can clearly display the lesions in HVs and the IVC, as well as in AHVs, and it has diagnostic and therapeutic value.

Diagnosis, treatment and outcome of hepatic venous outflow obstruction in paediatric liver transplantation: 24-year experience at a single centre

BACKGROUND

Hepatic venous outflow obstruction after paediatric liver transplantation is an unusual but critical complication.

OBJECTIVES

To review the incidence, diagnosis and therapeutic modalities of hepatic venous outflow obstruction from a large national liver transplant unit.

MATERIALS AND METHODS

During the period from October 1992 to March 2016, 917 liver transplant procedures were performed with all types of grafts in 792 children. Transplants suspected to have early or delayed venous outflow obstruction were confirmed by percutaneous venography or surgical revision findings. Therapeutic intervention, recurrence and outcome were evaluated.

RESULTS

Twenty-six of 792 children (3.3%) experienced post-transplant hepatic venous outflow obstruction. These patients had been diagnosed from 1 day to 8.75 years after transplantation. Six occurred during the early post-transplant period; in three of them, the graft was lost. Seventeen patients were initially treated by balloon angioplasty with success; 11 of these experienced recurrences. Four stents were implanted; one was complicated by definitive occlusion. Three of the five surgical revisions were successful. The initial stenosis involved the inferior vena cava in 10 grafts, in isolation or associated with hepatic vein involvement. Mean follow-up was 79 months after transplantation. Eight grafts were lost.

CONCLUSION

Acute postoperative hepatic venous outflow obstruction was associated with poor prognosis. Diagnostic venography should be performed if there is any suspicion of venous outflow obstruction, even if first-line examinations are normal. Stenosis frequently involved the inferior vena cava. Angioplasty was a safe and efficient treatment for venous outflow obstruction despite frequent recurrence.

A new discrete dipole kernel for quantitative susceptibility mapping

PURPOSE

Most approaches for quantitative susceptibility mapping (QSM) are based on a forward model approximation that employs a continuous Fourier transform operator to solve a differential equation system. Such formulation, however, is prone to high-frequency aliasing. The aim of this study was to reduce such errors using an alternative dipole kernel formulation based on the discrete Fourier transform and discrete operators.

METHODS

The impact of such an approach on forward model calculation and susceptibility inversion was evaluated in contrast to the continuous formulation both with synthetic phantoms and in vivo MRI data.

RESULTS

The discrete kernel demonstrated systematically better fits to analytic field solutions, and showed less over-oscillations and aliasing artifacts while preserving low- and medium-frequency responses relative to those obtained with the continuous kernel. In the context of QSM estimation, the use of the proposed discrete kernel resulted in error reduction and increased sharpness.

CONCLUSION

This proof-of-concept study demonstrated that discretizing the dipole kernel is advantageous for QSM. The impact on small or narrow structures such as the venous vasculature might by particularly relevant to high-resolution QSM applications with ultra-high field MRI - a topic for future investigations. The proposed dipole kernel has a straightforward implementation to existing QSM routines.

A study of clinical, radiological and etiological profile of cerebral venous sinus thrombosis at a tertiary care center

Background

A prospective, observational study was done at a tertiary care hospital in Western Maharashtra to describe the etiologies, clinical features, diagnosis and prognosis of cerebral venous sinus thrombosis in an Indian population.

Methods

54 patients with clinical and MRI features suggestive of cerebral venous sinus thrombosis (CVST), were studied with detailed clinical evaluation and pro-thrombotic work up. All were followed up monthly for 6 months, to assess the response to therapy and clinical outcomes.

Results

The mean age of presentation was 35 years. Headache was the most common presenting symptom (94%) and hemi paresis (22%) was the most common neurological sign. The most common sinus involved was transverse sinus in 77% of cases. In the unprovoked CVST subset (n = 29), elevated factor VIII (72%) and protein C deficiency (24%) were the common prothrombotic states identified. In the provoked CVST subset (n = 18), puerperium (44%) and para-infectious (22%) accounted for majority cases. Idiopathic CVST accounted for 13% (7/54) in this study. A Modified Rankin Scale (MRS) of 0-1 was achieved in 96% of patients at the end of 6 months follow up with no mortality in this study.

Conclusion

CVST is an important yet under recognized cause of intracranial hypertension and stroke in young. Clinical presentation is extremely varied and a high index of suspicion is needed. Magnetic Resonance Imaging (MRI) brain with Magnetic Resonance Venography (MRV) is the current diagnostic modality of choice. Elevated factor VIII and puerperium are the common etiologies in an Indian population. Management with anticoagulants is safe and has excellent clinical outcomes.

Management of major vascular injury during pedicle screw instrumentation of thoracolumbar spine

OBJECTIVES

Vascular injury is a rare complication of spinal instrumentation. Presentation can vary from immediate hemorrhage to pseudoaneurysm formation. In the literature, surgical approach to repair has varied based on anatomy, acuity of diagnosis, infection, and available technology. In this manuscript, we aim to describe our institutional experience with vascular injuries in thoraco-lumbar spine surgery.

PATIENTS AND METHODS

We report our institutional experience of three cases of vascular injury secondary to pedicle screw misplacement and their management, as well as a review of the literature.

RESULTS

The first case had a history of previous instrumentation and presented with back pain and fever. The patient was taken for instrumentation exploration via a posterior approach. Aortic violation was discovered at T6 intraoperatively during instrumentation removal and the patient underwent emergent endovascular repair. The second case presented with chronic back pain after multiple prior posterior fusions and CT angiogram showing screw perforation on the aorta at T10. The patient underwent elective endovascular repair with synchronous removal of the instrumentation. The third case presented with radicular leg pain 6 months after L4-S1 posterior lumbar interbody fusion, with CT scan demonstrating the left S1 screw abutting the L5 nerve root and common iliac vein. The patient underwent elective instrumentation revision with intraoperative venography.

CONCLUSION

Major vascular injury is a known complication of spinal surgery, especially if it involves instrumentation with pedicle screws. Treatment approach has evolved with the advancement of endovascular technology; however, open surgery remains an option when anatomy or infection is prohibitive. In the elective setting, preoperative planning with attention to surgical approach, positioning, and contingencies, should occur in a multidisciplinary fashion. Repair with an aortic stent-graft cuff may minimize unnecessary coverage of the descending thoracic aorta and intercostal arteries.

Cerebral Venous Sinus Thrombosis Secondary to Idiopathic Hypertrophic Cranial Pachymeningitis: Case Report and Review of Literature

BACKGOUND AND IMPORTANCE

Idiopathic hypertrophic cranial pachymeningitis (IHCP) is a rare fibrosing inflammatory process involving the dura mater. Currently, there is no consensus on the treatments for IHCP, and the usefulness of immunosuppressive agents as a first-line option remains controversial. Cerebral venous sinus occlusion (CVSO) and cerebral venous sinus thrombosis (CVST) secondary to IHCP, which may cause progressive intracranial hypertension and venous obstructive parenchymal lesions, make the diagnosis and treatment of IHCP more complicated.

METHODS

We present a case of IHCP. We also review previous cases of IHCP with secondary CVSO/CVST and then summarize the clinical characteristics of these patients.

CLINICAL PRESENTATION

A 52-year-old female patient with IHCP developed secondary CVST. She had a severe headache with a hyperintense lesion on computed tomography, which was considered as subarachnoid hemorrhage. Lumbar tapping with a cerebrospinal fluid test, in addition to gadolinium contrast-enhanced magnetic resonance imaging, suggested IHCP. Secondary CVST was identified by digital subtraction angiography and magnetic resonance venography. Fatal intracranial hypertension with severe neurologic deficits occurred, despite mannitol, furosemide, and corticoid therapy. After administration of intravenous pulse cyclophosphamide, she obtained complete remission.

CONCLUSIONS

We experienced a patient with CVST secondary to IHCP, who was successfully treated with cyclophosphamide pulse therapy. Because IHCP with secondary venous obstruction has various differential diagnoses, venography is necessary to avoid misdiagnosis. The use of immunosuppressive agents may be promising but needs further verification.

Diagnostic value of computerized tomography venography in detecting stenosis and occlusion of subclavian vein and superior vena in chronic renal failure patients

Introduction

Currently, venography is the standard diagnostic method to examine veins before implementing access, which is invasive in nature. Computerized tomography venography (CTV) can simultaneously indicate deep and superficial venous systems in the upper extremity and their relation to the surrounding anatomical structures; however, its diagnostic value in the detection of central venous disease has yet to be defined. The aim of this study was to determine the diagnostic value of CT venography compared to venography in the diagnosis of stenosis and the occlusion of subclavian veins and the superior vena in renal failure patients.

Methods

This cross-sectional study was conducted from January to September 2015 on patients with chronic renal failure undergoing upper extremity venography at the Radiology Department of Imam Reza Hospital in Mashhad, Iran. We excluded patients with catheters in their jugular and subclavian vein routes, venous hypertension with reverse-function fistula, or sensitivity to contrast agents. Several factors, including age, gender, catheterization record in jugular and subclavian veins, and fistula record in the upper extremity, as well as clinical symptoms consisting of edema, dermatitis, and ulcers in these organs, were recorded in the corresponding form. Then, the patients consecutively underwent indirect venography and CT venography and traces of stenosis (more than 50%) or complete occlusion in the subclavian vein and superior vena were recorded. The data were analyzed using SPSS software by the chi-squared test, and sensitivity, specificity, and positive and negative predictive values were calculated by means of MedCalc Online, version 16.2.

Results

The study was conducted on 40 patients (26 males and 14 females) with a mean age of 46.7 ± 10.4 years. In this study, 58 subclavian veins, as well as 32 superior vena cava, were studied. The results showed that the diagnostic value of CTV in the detection of subclavian stenosis had a sensitivity and a specificity of 88.2 and 97.5%, respectively. Moreover, in the superior vena cava, the greatest CTV diagnostic sensitivity and specificity was related to vein stenosis detection (sensitivity = 88.8%; specificity = 100%).

Conclusion

It seems that the CTV, based on its high sensitivity, specificity, and predictive value, can be used as an efficient tool in the study of stenosis in subclavian veins and superior vena in patients undergoing venography

Varicocele percutaneous embolization outcomes in a pediatric group: 7-year retrospective study

PURPOSE

Percutaneous embolization and surgical repair are the current treatment options for varicocele, but determining method superiority remains controversial. In this retrospective study, we evaluate the technical success, complication and recurrence rates following percutaneous embolization in a pediatric group, which were compared to reported outcomes for surgical repairs.

METHODS

Thirty children treated for percutaneous varicocele embolization were recruited. The side and grade of varicocele, symptoms, testicular asymmetry, mean recurrence time, total radiation dose and complications were evaluated. Recurrence and follow-up complications due to embolization were also reviewed.

RESULTS

The venography showed retrograde filling of the internal spermatic vein with the identification of aberrantly fed vessels in 23 % of patients. None of the patients suffered from procedure complications except one who had venous injury which was treated with a sclerosing agent. The technical success rate was 93 % (28 patients) with a recurrence rate of 13 % (4 patients). Interestingly, the mean radiation dose used was 862.5 µGy m(2), 3 times lower than abdominal CT.

CONCLUSION

Considering the intravascular nature of embolization, which aims to avoid testicular artery and spermatic cord damage (difficult to avoid with the surgical method), and consequently a lower complication rate, along with the same success rate and recurrence rate, our study supports that embolization is a superior method to surgical interventions.

The incidence of deep venous thrombosis before arthroscopy among patients suffering from high-energy knee trauma

PURPOSE

The purpose of the present study was to analyse the incidence of deep venous thrombosis (DVT) before knee arthroscopy in patients who had sustained high-energy knee injuries.

METHOD

This study included 64 patients who underwent arthroscopic knee surgery as a result of injury from a traffic accident or a high fall. Venography was performed on the injured leg of each patient before arthroscopy. The patients were divided into two groups based on whether they had DVT. Correlation analysis was performed to determine the factors associated with DVT.

RESULTS

A total of 32 (50 %) of the 64 patients had venographic evidence of DVT. Of these DVTs, seven were proximal (10.9 %). The D-dimer (DD) level was significantly higher in the DVT group, especially among the patients whose symptoms had persisted for more than 10 days. DVT is difficult to diagnose solely based on clinical symptoms, as some patients are symptomatic while others exhibit symptoms that could be attributed to trauma.

CONCLUSIONS

The incidence of DVT before knee arthroscopy in patients with high-energy knee injuries was 50 %, and the prevalence of proximal DVT was 10.9 %. DD is a sensitive marker for DVT. No patient developed DVT with a DD level lower than 0.8 mg/L, but those with DD level higher than 1.5 mg/L had a much higher incidence of DVT developing in patients who had been injured for more than 10 days. A routine examination to exclude DVT in these patients should be performed before arthroscopy.

LEVEL OF EVIDENCE

IV.

Complications of Permanent Hemodialysis Catheter Placement; Need for Better Pre-Implantation Algorithm?

There is a correlation between central venous cannulation and the development of central venous stenosis. Minor retrosternal vein lesions can be easily missed. Computerized tomographic (CT) venography is the diagnostic procedure of choice. The aim of this study was to examine the complications after catheter implantation in patients with prior permanent catheter placement and to evaluate present diagnostic procedures performed prior to choosing permanent access site in order to reduce possible complications after catheter placement. Complications of permanent CVC insertion in our department were analyzed between October 2011 and February 2015. We have implanted the Tesio twin catheter system and the Hickman Bard dual lumen catheter. All patients with prior permanent dialysis catheter were evaluated with color doppler, while patients with suspected central venous stenosis (CVS) or thrombosis were evaluated with phlebography or CT venography prior to catheter placement. One hundred and ninety-eight permanent dialysis catheters were placed (173 Tesio [87.4%] and 25 Hickman [12.6%]) in 163 patients. There were 125 patients (76.7%) with prior temporary catheter and 61 (48.8%) of them had more than one prior permanent catheter (1.92 catheter per person).There were 4/61 (6.5%) patients with catheter-related complications without prior phlebography and CT venography. Phlebography and CT venography were performed in 30 (24.0%) patients with suspected CVS/thrombosis and with dialysis vintage of 76.23 months (52.78-98.28). Phlebography and CT venography were more sensitive than color doppler in the detection of CVS/thrombosis in patients with prior permanent catheter placements (P < 0.001). Since this diagnostic algorithm was introduced prior to catheter placement there were no catheter insertion-related complications or dysfunctions (P < 0.001). All our procedures on patients with prior permanent catheters followed preliminary color doppler diagnostics. Nevertheless, in four cases, the vessel obstruction and abnormality led to catheter insertion-related complications. When phlebography and CT venography was performed before the procedure in patients with prior permanent catheters and one or more CVS or thrombosis, early and late catheter-related complications were avoided by careful selection of the least injured vein and planning of procedure. When planning a permanent dialysis catheter placement in patients with prior multiple CVC, phlebography and CT venography may be diagnostic procedures of choice for avoidance of early catheter dysfunction and CVC placement complications.

Lack of consistency in the relationship between asymptomatic DVT detected by venography and symptomatic VTE in thromboprophylaxis trials

Asymptomatic deep-vein thrombosis (DVT) detected by mandatory venography, a surrogate outcome, comprises most of the efficacy outcome events in recent thromboprophylaxis trials. The validity of this surrogate to estimate trade-off between thrombotic and bleeding events in these clinical trials requires a consistent relationship between asymptomatic DVT and symptomatic venous thromboembolism (VTE). In this systematic review of high quality VTE prevention trials, we examined the consistency of the ratios of asymptomatic DVT to symptomatic VTE across a broad range of indications. Studies were identified from citations listed in the chapters on VTE prevention in the antithrombotic guidelines by the American College of Chest Physicians, 2012. A study was eligible if it: 1) was a randomised trial comparing an anticoagulant with standard of care; 2) included at least 500 participants; 3) reported asymptomatic or all DVT rates; and 4) reported symptomatic VTE rates. Of the 26 eligible trials, 19 trials were conducted in orthopaedic patients, five in general surgery patients and two in general medical patients. The overall median rates (ranges) for asymptomatic DVT and symptomatic VTE were 9.11 % (0.75 to 54.87 %) and 0.49 % (0.00 to 3.10 %), respectively. The median ratio was 14.53, with a wide range (2.75 to 103.86). Wide variability in the ratios persisted despite indication- and anticoagulant-specific analyses. In VTE prevention trials of alternative anticoagulants, the wide variability in the ratios of asymptomatic DVT to symptomatic VTE precludes judging the trade-off between thrombotic and bleeding events on the basis of composite outcomes dominated by venographic DVT.

Prospective study to develop surface landmarks for blind axillary vein puncture for permanent pacemaker and defibrillator lead implantation and compare it to available contrast venography guided technique

OBJECTIVE

To develop surface landmarks for blind axillary vein puncture for pacemaker lead implantation.

METHODS AND RESULTS

Patients for routine coronary angiography were counseled for participating in our study. 20 patients who gave consent were taken up for axillary venogram after proper positioning at the time of coronary angiogram. The venograms of these 20 patients, were reviewed and the landmarks were used to develop a blind axillary puncture technique. Success rate of 100% was achieved with surface landmark guided axillary vein puncture. The implantation time while using surface landmark guided axillary puncture was not significantly longer than when venography based approach was used. Another interesting observation made from the study was that increasing BMI had a positive correlation with the time taken for venous access, the fluoroscopic time and the volume of contrast used, all the associations being statistically significant. Thus, the surface landmark guided technique is more safe and expeditious in non obese patients and probably in pediatric patients as well. Moreover, the new surface landmark guided approach is a significant safety step in terms of reducing the unwanted and avoidable radiation exposure to the hands.

CONCLUSION

The results of this study demonstrate that placement of endocardial permanent pacemaker and ICD leads via the developed surface landmarks is effective and safe and is devoid of the harmful effects of radiation and contrast exposure.

Usefulness of the computed tomography venography for evaluation of leg edema including deep vein thrombosis in rehabilitation patients

Objective

To investigate the usefulness of computed tomography venography (CTV) for evaluation of leg swelling, especially deep vein thrombosis (DVT), in rehabilitation patients.

Methods

A hundred twenty-three patients, who had performed CTV performed because of suspected DVT in our clinic, were enrolled. We performed chart reviews retrospectively and categorized CTV findings as follows: DVT distal to inguinal ligament and no compression lesion; DVT proximal to inguinal ligament and no compression lesion; DVT distal to inguinal ligament and anatomical variant (for example, May-Thurner syndrome); DVT due to compression of mass (cancer or cyst); DVT and other incidental abnormal finding; and no DVT and other possible causes of leg swelling.

Results

DVTs were found in 65 (53%) patients. DVTs were found at distal level (thigh or lower leg) to inguinal ligament in 47 patients. DVTs were found at proximal to inguinal ligament, usually undetectable with duplex ultrasonography, in 6 patients. DVTs caused by external compression, such as femoral vein and cancer mass, were found in 12 patients (10%), which are also not easily detected with duplex ultrasonography. Other various causes of leg edema without DVT were found in 22 (18%) patients.

Conclusion

CTV can evaluate more extensively venous problems in the pelvis and abdomen and detect other possible causes of leg swelling. Therefore, CTV can be a useful tool not only for easy detection of DVT but also for evaluating differential diagnosis of leg edema in rehabilitation patients.

MRI and venographic aspects of pelvic venous insufficiency

Pelvic venous insufficiency is a frequent pathology in multiparous women. Diagnosis can be made by chance or suspected in the case of symptoms suggesting pelvic congestion syndrome or atypical lower limb varicosity fed by pelvic leaks. After ultrasound confirmation, dynamic venography is the reference pretherapeutic imaging technique, searching for pelvic varicosity and possible leaks to the lower limbs. MRI is less invasive and allows a three-dimensional study of the varicosity and, with dynamic angiography, it can assess ovarian reflux. It also helps to plan or even sometimes avoid diagnostic venography.

The budd-Chiari syndrome in a child: a case report and review of the literature

The Budd-Chiari Syndrome is associated with hepatic venous outflow obstruction. This syndrome is rare in infants and children. As this syndrome is uncommon, especially in the paediatric age group, misdiagnoses and delays in the diagnosis are frequent. A high index of clinical suspicion along with a radiological aid and a histopathological correlation can lead to an early diagnosis and an appropriate management in such cases.This case report highlights the occurrence of this rare condition in the paediatric age group as well as it redefines the salient features of this syndrome.

Diagnosis and treatment of Budd-Chiari syndrome: An analysis of 59 cases

AIM: To analyze the clinical characteristics of Budd-Chiari syndrome to improve clinical awareness and diagnosis of this disease.

METHODS: The clinical data for 59 patients diagnosed with Budd-Chiari syndrome were reviewed retrospectively to analyze patients' clinical symptoms, signs, laboratory examination, iconography examination and treatment.

RESULTS: Main clinical manifestations included lower-limb edema (17/59, 28.8%), abdominal distention (15/59, 25.4%), and abdominal distention with lower limb edema (7/59, 11.9%). The rate of diagnosis of Budd-Chiari syndrome by color Doppler vascular ultrasound and angiography was nearly 100%. Of 55 patients undergoing interventional therapy, 23 were cured, 30 had improved condition, and 2 had no significant improvement.

CONCLUSION: Clinical manifestations of Budd-Chiari syndrome are complicated, which often leads to misdiagnosis and mistreatment. For patients highly suspected of having this disease, color Doppler vascular examination and venography should be conducted for diagnosis. Early diagnosis and treatment are important for prognosis. Interventional therapy is an effective method for Budd-Chiari syndrome.

Detection and Prevention of Post-Operative Deep Vein Thrombosis [DVT] Using Nadroparin Among Patients Undergoing Major Abdominal Operations in India; a Randomised Controlled Trial

Deep vein thrombosis [DVT] is one of the most dreaded complications in post-operative patients as it is associated with considerable morbidity and mortality. Majority of patients with postoperative DVT are asymptomatic. The pulmonary embolism, which is seen in 10% of the cases with proximal DVT, may be fatal. Therefore it becomes imperative to prevent DVT rather than to diagnose and treat. Only one randomized trial has been reported from India to assess the effectiveness of low molecular weight heparin in preventing post-operative DVT. To assess the risk of DVT in North Indian patients following major abdominal operations and to evaluate the effectiveness of Nadroparin, A Low Molecular Weight Heparin (LMWH) therapy in preventing post-operative DVT. Sixty five patients were randomised preoperatively into Group-I; Nadroparin prophylaxis and Group-II: No prophylaxis. The primary outcome was the occurrence of DVT, diagnosed by bilateral lower limb venogram performed, seven to ten days after operation. Secondary outcome measures included adverse effects of radio-opaque dye, intra-operative blood loss, operating time, postoperative platelet count, intraoperative blood transfusion requirements and the total duration of postoperative bed rest. No case of DVT occurred in either group. There was no statistical difference in the risk of secondary outcome measures in the two groups. DVT was not observed in any of the patients, even with several high risk factors indicating a possible protective mechanism in the North Indian population.

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.