Invasive Venography Research Articles

May-Thurner Anatomy in Patients With Chronic Thromboembolic Pulmonary Hypertension: An Important Clinical Association.

The aim of this study was to investigate the incidence of May-Thurner anatomy (MTA) in patients with chronic thromboembolic pulmonary hypertension (CTEPH) and identify its predictors. MTA is an anatomical variant characterized by compression of left common iliac vein by the overlying right iliac artery. Over time, this leads to venous intimal scarring, blood flow stasis, and the development of deep vein thrombosis (DVT). DVT is a known risk factor for the development of CTEPH. The prevalence of this anatomical variation in patients with CTEPH is unknown. A retrospective chart review was conducted in patients referred to Temple University Hospital's cardiac catheterization laboratory for the evaluation of CTEPH between January 2016 and June 2020. Among these patients, those who underwent invasive venography were evaluated for the presence of angiographic MTA. Multivariate regression was used to identify factors associated with presence of MTA. A total of 193 patients with CTEPH were referred for pulmonary angiography, of whom 148 patients underwent invasive venography. MTA was identified in 44 patients (29.7%). Factors associated with the presence of MTA were lower extremity DVT (odds ratio: 3.5; 95% confidence interval: 1.58-7.8; P=0.002), and left lower extremity post-thrombotic syndrome (odds ratio: 2.0; 95% confidence interval: 0.98-4.1; P=0.05). Patients with MTA were more likely to undergo pulmonary thromboendarterectomy than patients without MTA (79.5% vs 58.7%; P=0.015). MTA is very common in patients with CTEPH. History of lower extremity DVT and or left lowerextremity post-thrombotic syndrome was associated with the presence of MTA.

COMPLEX VENOUS THROMBOEMBOLISM DECISION-MAKING IN POSTPARTUM PATIENT

Background May-Thurner syndrome and pregnancy are independent risk factors for the development of deep vein thrombosis (DVT). Emerging data suggests an association for venous thromboembolism (VTE) development in COVID-19 patients. Treatments for DVT vary and include thrombolysis, mechanical thrombectomy and long-term anticoagulation. We describe a unique case of this in a postpartum female. Case A 31 year old female G3P0121 and recent cesarean section 1 month ago presented with left lower extremity swelling, severely limited ambulation and 3+ edema of the left leg extending to the hip without any right leg edema. She was COVID-19 antibody positive. Occlusive DVTs were confirmed via venous duplex ultrasound and computed tomographic venography of the abdomen and pelvis, extending from distal inferior vena cava to the left popliteal vein. Decision-making Invasive venography confirmed the non-invasive imaging findings. After administering 12-14 mg of tissue plasminogen activator (tPA), multiple aspirations were performed using a rheolytic thrombectomy catheter. However persistent dense thrombus in the iliac and femoral veins remained, thus subsequent balloon angioplasty was performed but unsuccessful. Intravascular ultrasound confirmed the presence of May-Thurner syndrome at the junction of the left common iliac vein and the inferior vena cava. Finally an infusion catheter was placed for tPA. Within 48 hours, patient developed oliguric renal failure likely due to a combination of contrast-induced and pigment nephropathy requiring intermittent hemodialysis. Repeat ultrasound showed resolution of DVT along with improving edema and renal function. Warfarin was chosen for long-term anticoagulation due to renal failure and breast-feeding. Conclusion Pregnancy is a pro thrombotic state that may lead to VTE even in the postpartum period. Decision-making and treatment in these patients may be complex and require a multidisciplinary approach.

Female pelvic congestion syndrome: how can CT and MRI help in the management decision?

Diagnosis of female pelvic congestion syndrome (PCS) is challenging. Although invasive venography is the gold-standard for diagnosis, however, CT and MRI are important in the assessment. In this study, we tried to highlight the role of CT and MRI as non-invasive tools in the diagnosis and management of PCS. This was a retrospective study of 50 patients confirmed clinically to have PCS. These patients had already done CT and MRI before venography or surgery. The mean age of the patients was 48 years ± 12 years SD. Vaginal discharge and pelvic heaviness were the commonest symptoms (46 and 42% respectively). The commonest risk factor was multiparity (56%) followed by the RVF uterus (26%). No significant difference was found between CT, MRI, and venography as regarding the diameter of the ovarian vein, diameter, and the number of the varicose veins. The sensitivity of CT and MRI was 94.8 and 96%. CT and MRI discovered five cases with local pelvic obstructing cause,14 cases with evidence of vascular compression syndrome, and the rest 31 cases diagnosed to have primary non-obstructing PCS which was effective in decision-making with the surgery indicated in the first group while stenting of the vascular obstruction followed by bilateral ovarian veins coiling was the better option for the second group and only bilateral coiling was needed for the last group. CT and MRI play important roles in the diagnosis and even management decision in cases of PCS. Identification of the importance of diagnostic radiology before management decisions of cases with PCS.

Autologous pericardium used for reconstruction of left innominate vein in patient with mediastinal venous aneurysm:a case report

BackgroundMediastinal venous aneurysm is a very rare disease and can be easily misdiagnosed. Patients are often asymptomatic while venous aneurysm of large size with adjacent structures oppressed can lead to discomfort. The surgical treatment for aneurysm of large vessels is often complex and challenging.Case presentationWe reported a 52-year-old man with mediastinal mass who received operation on July 2019 in our hospital. Left innominate vein aneurysm was diagnosed during operation with superior vena cava involved. The aneurysm was resected and pericardium was taken to repair part wall of superior vena cava and reconstruct left innominate vein. The patient’s postoperative course was uneventful.ConclusionsVenous aneurysm should be considered when mediastinal mass has no clear boundary with large veins or even seems to connect with them. Magnetic resonance imaging, computed tomographic angiography and invasive venography can be performed to further evaluate the mass once diagnosis of venous aneurysm was suspected. Using pericardium to repair large veins is a good choice which is safe and costless.

A72 VARICEAL BLEED & PORTAL HYPERTENSIVE GASTROPATHY IN A NON-CIRRHOTIC PATIENT WITH ISOLATED SPLENOMEGALY

Abstract Background Portal hypertension caused by cirrhosis is the most common etiology of esophageal varices. However, abnormalities of the spleno-portal axis in the absence of liver disease may also cause portal hypertension resulting in varices. We report a rare case of esophageal variceal bleed in a non-cirrhotic patient with isolated splenomegaly secondary to chronic G-CSF therapy. Aims This report outlines the case of a patient with Cohen Syndrome (CS) who presented with an upper gastrointestinal (GI) bleed in the setting of previously documented splenomegaly and portal hypertension. We expand on the clinical investigations, diagnosis, treatment plan and hospital course of this patient. Methods Case report, review of literature. Results A 26-year old male with previously diagnosed CS presented with large volume hematemesis and pancytopenia. CS is a rare autosomal recessive disorder. In our patient this manifested with congenital neutropenia, microcephaly, retinal dystrophy and global developmental delay. He required long term G-CSF therapy to manage chronic neutropenia and subsequently developed splenomegaly, a known side effect. The most recent MRI identified stable splenomegaly with a craniocaudal length of 23 cm, normal liver size and no radiographic evidence of cirrhosis. The imaging was also significant for gastroesophageal and splenorenal varices but no ascites or recanalization of the umbilical vein. A recent liver biopsy had shown mild pericellular fibrosis with no active liver disease or cirrhosis. In the past, the patient had declined EGD, therapeutic splenectomy or assessment of hepatic venous pressure gradient through invasive venography. His liver enzymes, bilirubin and albumin had always been within normal limits. The patient had no history of GI bleeding. Previous investigations for hematologic malignancies or myelodysplastic syndrome had been negative. Upon admission, an urgent EGD revealed active variceal bleeding in the esophagus and portal gastropathy. Given the extent of his congenital orofacial abnormalities a variceal band ligator could not be passed for appropriate intervention. The patient was transferred to the Intensive Care Unit and managed with intravenous proton pump inhibitor, octreotide, as well as transfusions of packed red blood cells, platelets and fresh frozen plasma. Within the next 48 hours, the patient underwent successful transjugular intrahepatic portosystemic shunt and CT-guided coil placements for the bleeding varices. Conclusions This is a rare case of variceal bleed in a non-cirrhotic patient with portal hypertension from iatrogenic splenomegaly. While there are previous reports of spontaneous splenic rupture secondary to G-CSF therapy we are the first to report variceal bleed as a complication. This is a life-threatening consequence that requires urgent intervention and intensive care. Funding Agencies None

Case series of seven women with uterine fibroids associated with venous thromboembolism and chronic thromboembolic disease

Uterine fibroids have been described as an associate to acute venous thromboembolism (VTE), with case reports showing an association between large uterine fibroids, acute deep venous thrombosis (DVT), and acute pulmonary embolism (PE). However, there is little known about the association or causation between uterine fibroids, chronic thromboembolic disease (CTED), and chronic thromboembolic pulmonary hypertension (CTEPH). We report on six women with uterine fibroids and CTEPH, as well as one woman with CTED, all of whom presented with exertional dyspnea, lower extremity swelling, and in the cases of CTEPH, clinical, echocardiographic, and hemodynamic evidence of pulmonary hypertension and right heart failure. Compression of the pelvic veins by fibroids was directly observed with invasive venography or contrast-enhanced computed tomography in five cases. All seven women underwent pulmonary thromboendarterectomy (PTE) followed by marked improvement in functional, clinical, and hemodynamic status.

A systematic review of venous aneurysms by anatomic location.

Venous aneurysms are uncommon vascular abnormalities that may be identified anywhere in the body. Historically, they were often misdiagnosed as soft tissue lesions, but with the advent of readily available noninvasive imaging (such as duplex ultrasound), they can now be easily identified. Our aim was to review the presentation of venous aneurysms, available imaging modalities for defining them, and management. The English-language literature before March 2017 was reviewed, and only reports of primary venous aneurysms of the deep veins were included. Reports were subdivided on the basis of the location of the venous aneurysm, and reports containing sample imaging studies were referenced from Elsevier publications. In total, our review identified reports of 35 head and neck venous aneurysms, 42 thoracic venous aneurysms, 152 intra-abdominal venous aneurysms, and 279 venous aneurysms of the extremities. Venous aneurysms of the lower extremity deep veins were most likely to be manifested by venous thromboembolic events, with approximately 25% to 50% of popliteal vein aneurysms presenting with pulmonary embolism. Diagnosis can be made by duplex ultrasound, computed tomography venography, magnetic resonance venography, or invasive venography. Management varies by location; most thoracic and head and neck aneurysms are observed, whereas venous aneurysms of the extremities are treated with surgical intervention, given the potential for venous thromboembolism. Few reports describe endovascular management of these lesions, so open surgical intervention remains the standard of care. Venous aneurysms are rare vascular malformations that occur throughout the body. Many are identified on routine imaging ordered for other indications, whereas venous aneurysms of the deep veins of the extremities are often manifested with venous thromboembolism. Management of these lesions is determined largely by location and the potential morbidity and mortality of the untreated aneurysms vs surgery; aneurysms of the head and neck and thorax are managed with observation and serial imaging over time, whereas those of the abdomen and extremities are treated with surgical intervention. Endovascular techniques continue to lack a defined role in their management, and the standard of care remains open repair, when indicated.

Noninvasive diagnostic tools for pelvic congestion syndrome: a systematic review.

IntroductionIn the work‐up of patients with suspected pelvic congestion syndrome, venography is currently the gold standard. Yet if non‐invasive diagnostic tools are found to be accurate, invasive venography might no longer be indicated as necessary.Material and methodsA literature search in Pubmed and EMBASE was performed from inception until 6 May 2017. Studies comparing non‐invasive diagnostic tools to a reference standard in the work‐up of patients with (suspected) pelvic congestion syndrome were included. Relevant data were extracted and methodological quality of individual included studies was assessed by the Quality Assessment of Diagnostic Accuracy Studies (QUADAS‐2) tool.ResultsNine studies matched our inclusion criteria. Six studies compared ultrasonography to venography and three studies described a magnetic resonance imaging technique. In using transvaginal ultrasonography, the occurrence of a vein greater than five mm crossing the uterine body had a specificity of 91% (95% CI; 77–98%) and occurrence of pelvic varicoceles a sensitivity and specificity of 100% (95% CI; 89–100%) and 83–100% (95% CI; 66–93%), respectively. In transabdominal ultrasonography, reversed caudal flow in the ovarian vein accounted for a sensitivity of 100% (95% CI; 84–100%). Detection of pelvic congestion syndrome with magnetic resonance imaging techniques resulted in a sensitivity varying from 88 to 100%.ConclusionsThe sensitivity of ultrasonography and magnetic resonance imaging seem to be adequate, which indicates a role for both tests in an early stage of the diagnostic workup. However, due to methodological flaws and diversity in outcome parameters, more high standard research is necessary to establish a clear advice for clinical practice.

Utility of magnetic resonance imaging in establishing a venous pressure gradient in a patient with possible nutcracker syndrome

Nutcracker syndrome is characterized by abnormal acute angulation of the superior mesenteric artery origin from the aorta, with resulting compression and hypertension of the crossing left renal vein. The radiologic studies used in diagnosis are typically limited to standard cross-sectional anatomic imaging with computed tomography or magnetic resonance imaging, with occasional use of Doppler ultrasound imaging for hemodynamic quantification. The standard for acquiring anatomic and physiologic information continues to be invasive venography. We describe the successful novel application of phase-encoded magnetic resonance imaging as a noninvasive method for acquiring anatomic and hemodynamic data in a case of possible nutcracker syndrome in a young patient.

Deep Vein Thrombosis and Pulmonary Embolism

This particular research was conducted in order to shed more light on the topic of Deep Vein Thrombosis (DVT) with the main complication of Pulmonary Embolism (PE). This specific topic came to mind as many of my family members, acquaintances and Asians in general deal with this problem on a daily basis. It is certainly a concerning issue especially in the developing world today. DVT most commonly involves the deep veins of the leg or arm, often resulting in potentially life-threatening emboli to the lungs or debilitating valvular dysfunction and chronic leg swelling. Over the past 25 years, the pathophysiology of DVT has become much better understood, and a great deal of progress has been made in its diagnosis and treatment. DVT is one of the most prevalent medical problems today, with an annual incidence of 80 cases per 100,000. Each year in the United States, more than 200,000 people develop venous thrombosis; of those, 50,000 cases are complicated by PE. Lower-extremity DVT is the most common venous thrombosis, with a prevalence of 1 case per 1000 population. In addition, it is the underlying source of 90% of acute PEs, which cause 25,000 deaths per year in the United States (National Center for Health Statistics [NCHS], 2006). Conclusive diagnosis has historically required invasive and expensive venography, which is still considered the criterion standard. The diagnosis may also be obtained noninvasively by means of ultrasonographic examination. Early recognition and appropriate treatment of DVT and its complications can save many lives. The goals of pharmacotherapy for DVT are to reduce morbidity, prevent post thrombotic syndrome (PTS), and prevent PE. The primary agents include anticoagulants and thrombolytics. Other than the immediate threat of PE, the risk of long-term major disability from postthrombotic syndrome is high.

Multiple Sclerosis - A Vascular Etiology?

From the earliest pathological studies the perivenular localization of the demyelination in multiple sclerosis (MS) has been observed. It has recently been suggested that obstructions to venous flow or inadequate venous valves in the great veins in the neck, thorax and abdomen can cause damaging backflow into the cerebral and spinal cord circulations. Paolo Zamboni and colleagues have demonstrated abnormal venous circulation in some multiple sclerosis patients using non-invasive sonography and invasive venography. Furthermore, they have obtained apparent clinical improvement or stabilization by endovascular ballooning of points of obstruction in the great veins in some, at least temporarily. If non-invasive observations by others validate their initial observations of a significantly increased prevalence of venous obstructions in MS then trials of angioplasty/stenting would be justified in selected cases in view of the biological plausibility of the concept.

Surveillance of Hemodialysis Vascular Access

A mature, functional arteriovenous (AV) access is the lifeline for a hemodialysis (HD) patient as it provides sufficient enough blood flow for adequate dialysis. As the chronic kidney disease (CKD) and end-stage renal disease (ESRD) population is expanding, and because of the well-recognized hazardous complications of dialysis catheters, the projected placement and use of AV accesses for HD is on the rise. Although a superior access than catheters, AV accesses are not without complications. The primary complication that causes AV accesses to fail is stenosis with subsequent thrombosis. Surveying for stenosis can be performed in a variety of ways. Clinical monitoring, measuring flow, determining pressure, and measuring recirculation are all methods that show promise. In addition, stenosis can be directly visualized, through noninvasive techniques such as color duplex imaging, or through minimally invasive venography. Each method of screening has its advantages and disadvantages, and several studies exist which attempt to answer the question of which test is the most useful. Ultimately, to maintain the functionality of the access for the HD patient, a team approach becomes imperative. The collaboration and cooperation of the patient, nephrologist, dialysis nurse and technician, vascular access coordinator, interventionalist, and vascular surgeon is necessary to preserve this lifeline.

May-Thurner Syndrome in Patients With Cryptogenic Stroke and Patent Foramen Ovale

We aimed to investigate the incidence of May-Thurner syndrome in patients with cryptogenic stroke with patent foramen ovale. This was a retrospective study. All consecutive patients with cryptogenic stroke having undergone patent foramen ovale closure from January 1, 2002, to December 31, 2007, at our institute were included in this study. Pelvic magnetic resonance venography studies of all patients were reviewed to determine if features of May-Thurner syndrome were present. Medical records and invasive venography studies of all patients were reviewed when available. All patients with May-Thurner syndrome features on magnetic resonance venography were reviewed by a vascular medicine specialist to define any previous incidence of deep vein thrombosis or any signs of chronic venous insufficiency. All patients also had lower limb venous duplex performed to rule out lower limb venous thrombosis. A total of 470 patients from January 1, 2002, until December 31, 2007, with cryptogenic stroke underwent patent foramen ovale closure at our institute. Thirty patients (6.3%) had features consistent with May-Thurner syndrome on magnetic resonance venography. These patients were predominantly female (80%) with a mean age of 43.6+/-11.9 years. Twelve patients (40%) had abnormalities in their laboratory thrombophilia evaluation and 13 females (54.1%) were taking hormone-related birth control pills. Only 2 patients had a history and signs of chronic venous insufficiency. All patent foramen ovales demonstrated right-to-left shunting on transesophageal echocardiography. Atrial septal aneurysms/hypermobile atrial septa were present in 70% of patients with May-Thurner syndrome. May-Thurner syndrome has an important clinical association with cryptogenic stroke and patent foramen ovale.

Abstract 687: Cardiac Imaging with Multi-Slice Computed Tomography and Echocardiography to Guide Left Ventricular Lead Placement in Resynchronization Therapy. The CAMERA Trial

Cardiac resynchronization (CRT) is associated with reverse ventricular remodeling and improved clinical outcomes, but is not successful in all patients. We looked at the feasibility of combined non-invasive imaging of the coronary veins and assessment of left ventricular dyssynchrony prior to pacemaker implantation and whether this combination would improve procedural success and patient outcome. Heart failure patients with standard indications for CRT were randomized to cardiac Multi-Detector CT (MDCT) plus Doppler echocardiographic assessment of left ventricular dyssynchrony versus conventional management prior to CRT. Co-registration of MDCT and tissue synchronization imaging data using a novel software program was performed and the results were used to optimize left ventricular lead placement for patients in the non-invasive imaging arm. 21 patients were enrolled with 9 patients randomized to the contemporary non-invasive imaging strategy and 12 patients randomized to the control group. MDCT correctly identified 19 of 24 (79%) coronary venous branches ≥ 2 mm in diameter when compared to invasive coronary venography. Patients in the non-invasive imaging group had a significant improvement in the 6 minute walk time on 6 month follow up (76.1 ± 48.4 meters vs 20.0 ± 64.8 meters, p = 0.04). Improvements in NYHA functional class and LV remodeling at 6 months were not significantly different in the non-invasive imaging and control arms. Left ventricular lead placement was successful in all patients, however more patients in the non-invasive imaging arm demonstrated LV lead placement in the most delayed or adjacent myocardial segment (8 of 9 vs 6 of 12, p = 0.09). Those patients with “optimal” lead placement showed a trend towards improved 6 minute walk times and improvement in left ventricular function 6 months after biventricular pacing. An imaging-guided strategy with coregistration of MDCT coronary venous anatomy and delayed myocardial segments by tissue Doppler echocardiography prior to CRT is feasible and may improve patient outcomes by facilitating optimal LV lead placement.

Noninvasive Imaging of Cardiac Venous Anatomy With 64-Slice Multi-Slice Computed Tomography and Noninvasive Assessment of Left Ventricular Dyssynchrony by 3-Dimensional Tissue Synchronization Imaging in Patients With Heart Failure Scheduled for Cardiac Resynchronization Therapy

Objectives of this study were to perform a prospective head-to-head comparison between multi-slice computed tomography (MSCT) venography and invasive venography in cardiac resynchronization therapy (CRT) candidates as well as to evaluate the relation between left ventricular (LV) lead position and effect on LV dyssynchrony and immediate response to CRT. Twenty-one consecutive heart failure patients scheduled for CRT implantation were prospectively enrolled to undergo 64-slice MSCT to visualize the venous system, invasive venography during device implantation, and tri-plane tissue synchronization imaging (TSI) before and after implantation. Excellent agreement between MSCT and invasive venography was noted. No significant differences were observed between both techniques regarding vessel diameters. In 12 patients, a match was observed between the area of latest mechanical activation (on TSI) and LV lead position. These patients showed a significant decrease in LV dyssynchrony (43 +/- 7 ms to 11 +/- 9 ms, p <0.0001) with acute reduction in LV end-systolic volume (188 +/- 54 ml to 162 +/- 48 ml, p <0.01) and improvement in LV ejection fraction (22% +/- 9% to 34% +/- 9%, p <0.01). Patients with a mismatch between area of latest activation and LV lead position remained dyssynchronous without improvement in LV function. In conclusion, visualization of major tributaries of the coronary sinus was comparable between invasive venography and MSCT venography. Optimal LV lead positioning in a vein draining the area of latest mechanical activation (determined from tri-plane TSI) resulted in acute improvement of LV dyssynchrony and systolic function after CRT implantation.

Noninvasive Evaluation of Cardiac Veins with 16-MDCT Angiography

Anatomic mapping of the cardiac veins is important to guide transvenous therapeutic procedures such as biventricular pacing. As an alternative to invasive venography, we studied the feasibility of MDCT of the cardiac venous anatomy. Cardiac venous anatomy is variable. MDCT is a noninvasive method that allows detailed imaging of the cardiac venous anatomy, including small cardiac veins and thebesian valves. Therefore, cardiac MDCT may be a valuable tool for guiding procedures that involve the cardiac venous system.

Early and long-term clinical and radiological follow-up results of expanded-polytetrafluoroethylene-covered stent-grafts for transjugular intrahepatic portosystemic shunt procedures.

The purpose of this study was to assess the therapeutic efficacy and immediate and long-term safety of expanded-tetrafluoroethylene covered stent-grafts for transjugular intrahepatic portosystemic shunts in patients with portal hypertension-related complications. A cohort of 56 patients suffering from severe portal hypertension-related complications underwent implantation of an expanded-polytetrafluoroethylene-covered stent-graft. All patients suffered from severe liver cirrhosis graded Child-Pugh A (n=8; 16%), B (n=13; 21%) or C (n=35; 63%). In 44 patients, the stent-graft was placed during the initial TIPS procedure (de novo TIPS); in the other 12 patients, the stent-graft was placed to repermeabilize the previously placed bare stent (TIPS revision). Follow-up was performed with clinical assessment, duplex ultrasound and, if abnormal or inconclusive, with invasive venography and pressure measurements. Per- en immediate post-procedural complications occurred in four patients (4/56, 7%). None of them was lethal. During follow-up, stent occlusion appeared in one patient and stenosis in two; no recurrence of bleeding was noted in all patients treated for variceal bleeding (n=28), and 24 of the 28 patients (86%) suffering from refractory ascites and/or hepatic hydrothorax were free of regular paracenteses and/or drainage of pleural effusion after shunt creation. The 30-day and global mortality for the total study population (n=56) was, respectively, 7% (n=4) and 28.5% (n=16). In the patient subgroup with variceal bleeding (n=28), 30-day mortality was 3.5% (n=1) and global mortality 14.2% (n=4). In the ascites and/or hydrothorax subgroup (n=28), 8.1% (n=3) mortality at 30 days was found and global mortality was 32.4% (n=12). In 10 patients of the 56 studied patients (18%), isolated hepatic encephalopathy occurred, which was lethal in 4 (Child C) patients (7%). Three of these four patients died within the 1st month after TIPS placement. A very high primary patency rate of TIPS can be obtained long-term after implantation of an e-PTFE-covered stent-graft, leading to a definitive resolution of portal hypertension-related complications. The incidence of TIPS-induced hepatic encephalopathy is acceptable.

Nutcracker phenomenon demonstrated by three-dimensional computed tomography

We report a 15-year-old girl with nutcracker syndrome (NCP) in whom three-dimensional helical computed tomography (3D helical CT) was useful for diagnosis; angiographic imaging using 3D helical CT provided fine outlines of the vascular structures in NCP, i.e., a compression of the left renal vein between the aorta and the superior mesenteric artery and the abnormal acute angle between them. Thus, a 3D helical CT enables precise depiction of the anatomical characteristics of renal vasculature and, therefore, may be a useful alternative imaging technique instead of conventional examinations, such as invasive venography or digital subtraction angiography. Further study in a large number of children with vascular abnormalities would be worthwhile.

Valve Injury

The anatomic appearance and competency of internal jugular valves were investigated in both cadavers and surgical patients. In 20 cadavers, the internal jugular vein (IJV) was dissected and the appearance of the valves observed. In two adult patients, the movements of the valves were observed by endoscopic visualization using an intravascular fiberscope, ultrasound techniques, and invasive venography. Transvalvular pressure gradients were measured in 10 adult surgical patients to examine the competence of the jugular venous valve. Nineteen internal jugular valves obtained from the 20 cadavers were situated directly above the termination of the IJV in the inferior bulb and were usually bilateral. The remaining 21 valves could not be examined since they had been already dissected out for another anatomical studies. The valves in 16 of the subjects were bicuspid and semiluminar. Two valves had a single cusp. The opening and closing of the valve was visualized easily with both a fiberscope and real-time ultrasound technique. Eight patients with normal central pressure had competent valves during cough-induced transvalvular pressure gradients of 45.3 +/- 10.1 (mean +/- SD) mmHg. Four valves from two cadavers remained competent at 75.4 +/- 18.2 mmHg, but became incompetent at 5.6 +/- 4.8 mmHg after a hole was made with a 14-gauge needle. Our results indicate that the IJV valve is located 0.5-2.0 cm above the union of the subclavian vein and IJV, and plays an important role in preventing retrograde blood flow to the brain.(ABSTRACT TRUNCATED AT 250 WORDS)

Deep Venous Thrombosis in Orthopaedic Patients

The diagnosis of deep vein thrombosis after total joint arthroplasty is difficult. The most widely used method of detection is physical examination and selective venography, which are unreliable and expensive even when symptoms and signs are prominent. This study employed computerized strain gauge plethysmography (CSGP) to select symptomatic patients for venography. The incidence of detection by CSGP was increased from 16% to 81.7%. Repeated CSGP also was investigated, but although specificity was further enhanced, it was at the expense of sensitivity. The negative predictive value of the CSGP screening was high and comparable to that of venography and indicates that CSGP is useful in the management of patients with symptoms suggestive of deep vein thrombosis. Computerized strain gauge plethysmography results emphasize the low specificity and poor feasibility of clinical examination and venography. Computerized strain gauge plethysmography is strongly advocated as a selection procedure for invasive venography in total joint arthroplasty patients.