Three-dimensional spiral CT venography for the pre-operative assessment of varicose patients

Vicious Circle With Venous Hypertension, Irregular Flow, Pathological Venous Wall Remodeling, and Valve Destruction in Chronic Venous Disease: A Review

Substantial advances occurred in phlebological practice in the last two decades. With the use of modern diagnostic equipment, the patients' venous hemodynamics can be examined in detail in everyday practice. Application of venous segments for arterial bypasses motivated studies on the effect of hemodynamic load on the venous wall. New animal models have been developed to study hemodynamic effects on the venous system. In vivo and in vitro studies revealed cellular phase transitions of venous endothelial, smooth muscle, and fibroblastic cells and changes in connective tissue composition, under hemodynamic load and at different locations of the chronically diseased venous system. This review is an attempt to integrate our knowledge from epidemiology, paleoanthropology and anthropology, clinical and experimental hemodynamic studies, histology, cell physiology, cell pathology, and molecular biology on the complex pathomechanism of this frequent disease. Our conclusion is that the disease is initiated by limited genetic adaptation of mankind not to bipedalism but to bipedalism in the unmoving standing or sitting position. In the course of the disease several pathologic vicious circles emerge, sustained venous hypertension inducing cellular phase transitions, chronic wall inflammation, apoptosis of cells, pathologic dilation, and valvular damage which, in turn, further aggravate the venous hypertension.

CT venography combined with ultrasound-guided minimally invasive treatment for recurrent varicose veins: a pilot paired-design clinical trial

AIM

To compare 1-year outcomes of computed tomography venography (CTV) combined with ultrasound-guided minimally invasive treatment with ascending phlebography and ultrasound-guided treatment for recurrent varicose veins.

MATERIALS AND METHODS

Consecutive patients with unilateral recurrent varicose veins were matched by gender, age, C classification, and degree of obesity, and randomised in a 1:1 ratio to receive either CTV (CTV group) or ascending phlebography (control group) combined with ultrasound-guided minimally invasive treatment. Patients were followed up by clinical and ultrasound examination. Follow-up was scheduled at 1 week, and 3, 6, and 12 months. The primary outcome measure was the Venous Clinical Severity Score (VCSS) at 12 months. Measures of secondary outcome included Chronic Insufficiency Venous International Questionnaire-20 (CIVIQ-20) score, recurrence of varicose vein or ulcer during 12 months, ulcer healing time, detection and location of treated veins.

RESULTS

Eighty patients were enrolled. Median VCSS in the CTV group was lower than it in the control group (p=0.04) and the CIVIQ-20 score was higher than the control group (p=0.02). By 12 months, no symptomatically recurrent varicose veins or ulcers had occurred. The ulcer healing time in CTV group was shorter (p<0.01). A greater number of patients had treated veins detected using CTV than by ascending venography (p=0.01), especially among patients with recurrence reflux veins in the groin, perineum, and vulva (p<0.01).

CONCLUSION

CTV combined with ultrasound may be more helpful than ascending phlebography combined with ultrasound to improve treatment efficacy for recurrent varices. These results should be verified by an future study with more patients and long-term follow-up.

[Connection of perforating and intramuscular veins of the crus in varicosity]

AIM

This study was undertaken to investigate the clinical anatomy of indirect perforating veins and their connection to the intramuscular venous collector of the crus by means of MSCT phlebography.

PATIENTS AND METHODS

From 2015 till now, MSCT phlebography was used to examine a total of 400 patients with chronic diseases of lower limb veins. According to the CEAP classification, clinical class C0-C1 was present in 108 (27%) subjects, C2-C3 - in 173 (43.3%) patients, and C4-C6 - in 119 (29.7%) patients. All examinations were performed using a 128-slice multispiral CT scanner Philips Ingenuity, followed by 3D reconstruction with the help of the IntelliSpace Portal Image Editing Software package.

RESULTS

In the 400 extremities examined, we identified a total of 11 655 indirect perforating veins of the calf. Studying the anatomical localization of perforating veins demonstrated that 3248 veins belonged to the posterior tibial group, 1830 veins - to the lateral group, 873 veins - to the paraachillary group, 276 veins - to the intergemellary group, 4451 veins - to the medial group, and 997 perforating veins - to the lateral group. 3D imaging made it possible to trace the entire course of the perforating veins originating from the posterior arched, intersaphenous, oblique veins or other communicating branches to the subfascial and intramuscular portions to the connection with the gastrocnemius and soleus veins which as the disease progresses undergo ectasia with the formation therein of pathological segmental hypervolemia.

CONCLUSION

Studying the ratio of the revealed indirect perforating veins of the determined groups and the presence of gradually developing ectasia of the intramuscular venous collectors in patients of various clinical classes from C0-C1 to C4-C6 made it possible to draw a conclusion on the involvement of perforating veins and intramuscular veins of the crus into the common pathohaemodynamic circle of the development and progression of chronic venous insufficiency in patients with varicose veins.

Anatomy of the lymph node venous networks of the groin and their investigation by ultrasonography

OBJECTIVE

To describe the anatomy of the lymph node venous networks of the groin and their assessment by ultrasonography.

MATERIAL AND METHODS

Anatomical dissection of 400 limbs in 200 fresh cadavers following latex injection as well as analysis of 100 CT venograms. Routine ultrasound examinations were done in patients with chronic venous disease.

RESULTS

Lymph node venous networks were found in either normal subjects or chronic venous disease patients with no history of operation. These networks have three main characteristics: they cross the nodes, are connected to the femoral vein by direct perforators, and join the great saphenous vein and/or anterior accessory great saphenous vein. After groin surgery, lymph node venous networks are commonly seen as a dilated and refluxing network with a dystrophic aspect. We found dilated lymph node venous networks in about 15% of the dissected cadavers.

CONCLUSION

It is likely that lymph node venous networks represent remodeling and dystrophic changes of a normal pre-existing network rather than neovessels related to angiogenic factors that occur as a result of an inflammatory response to surgery. The so-called neovascularization after surgery could, in a number of cases, actually be the onset of dystrophic lymph node venous networks.Lymph node venous networks are an ever-present anatomical finding in the groin area. Their dilatation as well as the presence of reflux should be ruled out by US examination of the venous system as they represent a contraindication to a groin approach, particularly in recurrent varicose veins after surgery patients. A refluxing lymph node venous network should be treated by echo-guided foam injection.

Female Pelvic Vein Embolization: Indications, Techniques, and Outcomes

Until recently, the main indication for pelvic vein embolization (PVE) in women was to treat pelvic venous congestion syndrome (PVC) but increasingly, patients with refluxing pelvic veins associated with leg varicosities are also being treated. A more unusual reason for PVE is to treat pelvic venous malformations, although such lesions may be treated with sclerotherapy alone. Embolotherapy for treating PVC has been performed for many years with several published studies included in this review, whilst an emerging indication for PVE is to treat lower limb varicosities associated with pelvic vein reflux. Neither group, however, has been subjected to an adequate randomized, controlled trial. Consequently, some of the information presented in this review should be considered anecdotal (level III evidence) at this stage, and a satisfactory ‘proof’ of clinical efficacy remains deficient until higher-level evidence is presented. Furthermore, a wide range of techniques not accepted by all are used, and some standardization will be required based on future mandatory prospective studies. Large studies have also clearly shown an unacceptably high recurrence rate of leg varicose veins following venous surgery. Furthermore, minimally or non-invasive imaging is now revealing that there is a refluxing pelvic venous source in a significant percentage of women with de novo leg varicose veins, and many more with recurrent varicosities. Considering that just over half the world’s population is female and a significant number of women not only have pelvic venous reflux, but also have associated leg varicosities, minimally invasive treatment of pelvic venous incompetence will become a common procedure.

Anatomy of the Hunter's canal and its role in the venous outlet syndrome of the lower limb

BACKGROUND

The "Adductor canal syndrome" has been described as an unusual cause of acute arterial occlusion inside the Hunter's canal in young sportsmen. It may also produce a compressive neuropathy of the saphenous nerve. To our knowledge, femoral vein compression in the canal has never been reported.

OBJECTIVE

To describe the anatomy, to propose a physiology of this canal, and to show that the femoral vein is much more exposed than the artery to compression inside this adductor hiatus, particularly at the outlet.

MATERIAL AND METHODS

The whole adductor canal was exposed in 100 limbs for anatomical study following latex injection. A series of 200 phlebographies and 100 CT venograms were also analyzed.

RESULTS

Anatomically, we found a musculotendinous band called the "vastoadductor membrane," which jointed the adductor tendon to the vastus medialis in all the cases. The femoral vein, located more posteriorly, was frequently narrowed at this level. This band can create a notch with a venous stenosis at the outlet of the Hunter's canal, usually located 12-14 cm above the femoral condyle. Two femoral valves constitute the landmark of the canal on the venograms: the lower is just below the outlet, 9 cm above the condyle. The second valve is 3 cm higher inside the canal.Functionally, the cadaveric simulations showed that the contraction of the adductor longus closes the hiatus, while the adductor magnus opens it. Our hypothesis is that Hunter's canal prevents femoropopliteal axis reflux by synchronizing with calf pump ejection during ambulation.

CONCLUSION

Compression of the femoral vein inside the adductor's canal is an underestimated and misdiagnosed cause of postural stenosis of the femoral vein. Ultrasound investigation of both limbs in patients with chronic venous disease (CVD) should be systematically carried out at this precise level in order to prevent future occlusion and onset of acute deep vein thrombosis.

Anatomy of the veno-muscular pumps of the lower limb

OBJECTIVE

To study the anatomy of the veno-muscular pumps of the lower limb, particularly the calf pump, the most powerful of the lower limb, and to confirm its crucial importance in venous return.

METHODS

In all, 400 cadaveric limbs were injected with green Neoprene latex followed by an anatomical dissection.

RESULTS

The foot pump is the starter of the venous return. The calf pump can be divided into two anatomical parts: the leg pump located in the veins of the soleus muscle and the popliteal pump ending in the popliteal vein with the unique above-knee collector of the medial gastrocnemial veins. At the leg level, the lateral veins of the soleus are the bigger ones. They drain vertically into the fibular veins. The medial veins of the soleus, smaller, join the posterior tibial veins horizontally. At the popliteal level, medial gastrocnemial veins are the largest veins, which end uniquely as a large collector into the popliteal vein above the knee joint. This explains the power of the gastrocnemial pump: during walking, the high speed of the blood ejection during each muscular systole acts like a nozzle creating a powerful jet into the popliteal vein. This also explains the aspiration (Venturi) effect on the deep veins below. Finally, the thigh pump of the semimembranosus muscles pushes the blood of the deep femoral vein together with the quadriceps veins into the common femoral vein.

CONCLUSION

The veno-muscular pumps of the lower limb create a chain of events by their successive activation during walking. They play the role of a peripheral heart, which combined with venous valves serve to avoid gravitational reflux during muscular diastole. A stiffness of the ankle or/and the dispersion of the collectors inside the gastrocnemius could impair this powerful pump and so worsen venous return, causing development of severe chronic venous insufficiency.

Underlying deep venous abnormalities in patients with unilateral chronic venous disease

Objectives

To report our initial experience using direct multidetector computed tomography venography (MDCT-V) for imaging lower limb deep veins. CT findings in limbs with chronic venous disease (CVD) were compared with contralateral healthy limbs.

Methods

MDCT-V with bilateral direct pedal injection of contrast was used to image the deep veins in both lower limbs. Eight patients with unilateral lower limb CVD of varying severity (according to the Clinico-Etiological-Anatomical and Pathological classification [CEAP] class 2-6) were studied. Five patients had primary CVD, while three patients had CVD secondary to previous deep vein thrombosis.

Results

Deep venous obstruction (>50%) or occlusion was identified in all CVD limbs and was not seen in contralateral healthy limbs. These lesions were not only iliac, were not exclusively present in advanced CVD and were independent of the presence or absence of deep venous reflux.

Conclusion

Morphologically significant lesions could be underlying in patients with clinically significant CVD. Direct MDCT-V provides clear reconstructable cross-sectional images of the whole deep venous tree, including infrainguinal areas, beyond the reach of intravascular ultrasound. Utilization of new venous imaging modalities may uncover previously undiagnosed and potentially treatable venous pathology in patients with CVD.

Three-dimensional modelling of the venous system by direct multislice helical computed tomography venography: technique, indications and results

The aim of multislice helical computed tomography venography (CTV) is to provide a precise, global and three-dimensional (3D) anatomical depiction of the venous network of the lower limbs. A multislice and multidetector spiral CT acquisition of the lower limbs with contrast injection of the dorsal foot produces about 1000 slices in 30 seconds. Dedicated volume-rendering software can compute a realistic and interactive 3D model of the venous system in realtime. This new tool furnishes an accurate 3D representation of the whole venous system of the lower limb with a realistic 3D model of the limbs, providing a road map of the varicose networks complementary to the duplex ultrasound (DUS). CTV allows a complete morphological study of the deep veins, including the detection of anatomical variations and proximal venous obstruction, not easily detectable by DUS. In the case of deep vein thrombosis, it has been shown to be a good diagnostic tool, well correlated with sonography. It also demonstrates, in some cases, haemodynamic patterns which are not available by DUS, particularly for perforator veins and congenital vascular malformations. The use of virtual reality techniques enables a complete anatomical study of both deep and superficial veins including a virtual dissection of the limbs. CTV is also a great educational tool to learn anatomy of the venous system and a powerful research tool to improve our knowledge of venous anatomy.

Anatomy and embryology of the small saphenous vein: nerve relationships and implications for treatment

The aim of this paper is to describe the anatomical relations of the small saphenous vein (SSV) in order to define the high-risk zones for the treatment of chronic venous disease. The SSV runs in the saphenous compartment demarcated by two fascia layers: a muscular fascia and a membranous layer of subcutaneous tissue. The clinician should be keenly aware of the anatomical pitfalls related to the close proximity of nerves to the SSV in order to avoid their injury: At the ankle, the origin of the SSV is often plexiform, located deep below the fascia, and the nerve is really stuck to the vein. The apex of the calf is an area of high risk due to the confluence of nerves which perforate the aponeurosis. Moreover, the possible existence of a 'short saphenous artery' which poses a high risk for injection of a sclerosing agent due to a highly variable disposition of this artery surrounding the SSV trunk. For this reason, procedures under echo guidance in this area are mandatory. The popliteal fossa is probably a higher risk zone due to the vicinity of the nerves: the small saphenous arch is close to the tibial nerve, or sometimes the nerve of the medial head of the gastrocnemius muscle. In conclusion, before foam injection or surgery, a triple mapping of the small saphenous territory is mandatory: venous haemodynamical mapping verifying the anatomy that is highly variable, nerve mapping to avoid trauma of the nerves and arterial mapping. This anatomical study will help to define the main high-risk zones.

Anatomy of the foot venous pump: physiology and influence on chronic venous disease

The aim of this paper is to demonstrate the location of the venous foot pump using an anatomical study. Four hundred cadaveric feet were injected with green neoprene latex followed by a dissection. A coloured segmentation of the venous system was achieved. The Lejars’ concept of the venous sole of the foot is incorrect: the true blood venous reservoir of the foot is located deeply in the plantar veins, between the plantar muscles. The medial and mostly lateral plantar veins converge into the plexus shaped calcaneal crossroad, where the blood is ejected upwards into the two posterior tibial veins. In addition, the several medial perforators of the foot directly connect the deep system (medial plantar veins) to the superficial venous system (medial marginal vein). This forms a true ‘medial functional unit’ which is unique in the limb given its directional flow is from deep to superficial. In conclusion, the plantar veins play an important role in the physiology of the venous return since a venous reservoir of 25 mL of blood is mobilized upwards with each step during walking. Therefore, the impairment of the foot pump by a static foot disorder should be considered as an important risk factor for chronic venous disease, and should be evaluated and corrected in any patient with venous insufficiency.

Preoperative determination of anatomic variations of the small saphenous vein for varicose vein surgery by three-dimensional computed tomography venography

Objective

To define the anatomical variations of small saphenous vein (SSV) for varicose vein (VV) surgery by three-dimensional computed tomography venography (3D-CTV) and to analyse the impact of this preoperative evaluation on surgical outcomes.

Methods

A total of 120 consecutive limbs with SSV insufficiency having undergone VV surgery from January 2005 until December 2007 were enrolled. The medical records and images were analysed retrospectively.

Results

The relationship between SSV and gastrocnemial vein (GNV) were categorized into two: (a) SSV and GNV drained to popliteal vein (PV) separately (100 limbs, 87%) and (b) SSV and GNV made common channel which drained to PV (15 limbs, 13%). Saphenopopliteal junction morphology was normal (75 limbs), severe tortuosity near PV (19 limbs), ampullary ectasia (4 limbs) and duplicated drainage to PV (2 limbs). No recurrence of VV was noted.

Conclusions

CTV can provide thorough preoperative anatomic information of the SSV variations and reduce the recurrence of VV.

Three-dimensional CT Venography: A Diagnostic Modality for the Preoperative Assessment of Patients with Varicose Veins

OBJECTIVE

We preoperatively assessed varicose veins by means of computed tomography (CT) with contrast injection in the veins of the lower extremity (CT venography). This paper reports the procedures, results and implications of CT venography from the surgical aspect.

METHODS

A total of 48 legs in 39 patients were examined. Contrast medium was diluted ten-fold and injected into the lower extremity veins, often using a dual route of injection. The images were reconstructed with the volume-rendering method.

RESULTS

CT venography clearly visualized the veins with a small amount of contrast medium and facilitated the identification of anatomy that was not suitable for passing the stripper. In addition, CT venography helped identify unusual types of varicose veins or uncommon sites of inflow of small saphenous veins. Such information was helpful for avoiding unexpected vascular injury or for minimizing skin incision. Dual-route injection was beneficial to minimize the blind zones. Doppler ultrasound could be more focused on hemodynamic assessment and determination of incision sites.

CONCLUSIONS

CT Venography is feasible in all cases of varicose veins. When performed in conjunction with ultrasonography, it appears to facilitate the safe and efficient treatment of various types of varicose veins.

Role of three-dimensional computed tomography venography as a powerful navigator for varicose vein surgery

PURPOSE

Computed tomography venography (CTV) with three-dimensional reconstruction can provide complementary road maps for varicose vein (VV) surgery. The purpose of this study is to verify the role of CTV in the treatment of VV in terms of advantages and complications.

METHODS

Ninety-four consecutive patients with VV underwent conventional high ligation, stripping, and varicosectomy by a single vascular surgeon in 2007. All patients were evaluated with duplex ultrasound and CTV. Patients with renal dysfunction, allergy to radiocontrast, telangiectasia only, or treated by endovenous laser therapy (EVLT) were excluded from the study. Computed tomography (CT) examination was performed with a 16-Multidetector CT scanner (Siemens, Erlangen, Germany) and 3D images were reconstructed by personal computer-based software (Rapidia, Infinitt, Seoul, Korea). Medical records and the CT images were reviewed retrospectively.

RESULTS

VV surgeries were done in 127 limbs of 94 patients (both in 33, right in 29, and left in 32). There were 56 females and 38 males with the mean age of 57 years (range, 28-79 years). The CEAP classification was C(2-3) EpAsPr. Perforators larger than 1 mm near the varicose veins were detected and marked on the CT volume-rendering images. The average numbers of perforators marked by CTV were 12.07 +/- 4.27 in each limb. The perforators were evaluated by duplex for the presence of reflux (>or=0.5 sec). Mean number of perforators with reflux in each limb was 1.41 +/- 1.67, which were ligated during the surgery. Incidental detections of other disease were done in six patients, including uterine myomas, an ovarian cyst, a gallstone, a scrotoal varicocele, and a pes anserine bursitis. Operation was performed with the CTV images on screen. CTV was helpful in designing the operation in most patients. Three-D CTV images of saphenopopliteal junction especially provided thorough understanding of the complex variable anatomy of the lesion. There were no CT-related complications, such as renal dysfunction or allergic reaction.

CONCLUSIONS

CT venography can provide excellent road map for VV surgery without significant complications. It cannot replace duplex ultrasound, but can provide powerful 3D images for designing operation as well as education and research.

[3D modeling in the field of morphology: methods, interest and results]

The aim of this paper is to show the major role played by the new computerized imaging tools available today in the fields of morphology and anatomy. For anatomical studies or educational purpose, they enhance the classical techniques. The 3D reconstruction, already used in daily clinical practice, will be the basis for computation of validated volumetric protocols enhancing our diagnosis and prognosis means. It is also a fantastic educational tool: the interactivity makes it simple, efficient, attractive and easily accessible and diffusable. For the research, mathematical modeling of embryogenesis and morphogenesis using finite elements method will open new ways for biomecanics and a dynamic quantification approach.