Alberto Caggiati

Fascial Relationships of the Long Saphenous Vein

The long saphenous vein runs constantly in a deep plane of the hypodermis, lying directly above the muscular fascia (Figure 1⇓). It is covered for its full length by a connective lamina that descends from the inguinal ligament to the ankle in the hypodermis of the medial thigh and leg. This lamina, which is formed by the interlacing of the hypodermal connective sheets, until now has been only partially described,1 and it is called the “saphenous fascia” to distinguish it from similar structures present in other regions of the human body.2 After having arched over the long saphenous vein, this hypodermic fascia fuses with the muscular fascia, thus delimiting a flat, fatty, continuous space from the groin to the ankle (Figure 2A⇓). This space could be considered the “saphenous compartment,”1 because it is clearly circumscribed and is occupied only by the saphenous vein and nerve (Figure …

Fascial relations and structure of the tributaries of the saphenous veins.

The objective was to define planar anatomy, fascial relationships and structure of the tributary vessels (TVs) of the saphenous veins (SVs). The gross anatomy of the TVs was evaluated by dissection in cadaver limbs and by sonography and computerized tomography in healthy volunteers. Correlated light microscopy and scanning electron microscopy were used to evaluate and compare the wall structure in 45 specimens of SVs and 122 specimens of TVs. The TVs showed a subdermal path and were surrounded by an amorphous fatty tissue. Only the “Giacomini’s vein” and the cranial segment of the “anterior accessory saphenous vein” ran deeply in the hypodermis, ensheathed by the muscular fascia and the membranous layer of the hypodermis. The wall of the TVs was weaker than that of the SVs due to the absence of intimal hyperplasia, to lesser muscularization and to scarce connective tissue proliferation. The absence of any fascial ensheathing and the parietal weakness are suggestive of a lower resistance of the TVs wall to increased endovascular pressure. This would explain why varicose changes occurring in the TVs are usually greater than those occurring in the affected SVs.

THE LONG SAPHENOUS VEIN COMPARTMENT

Objective: To define the relationship between the long saphenous vein and the connective framework of the subcutaneous tissue (hypodermis) of the lower limb. Methods: The connective skeleton of the hypodermis was studied by anatomical dissection, stereomicroscopy of cross-sectioned specimens and ultrasound imaging in 88 lower extremities. Results: The long saphenous vein runs for most of its length in a narrow compartment delineated deeply by the muscular fascia and superficially by a connective tissue lamina descending from the inguinal ligament in the anteromedial part of the thigh and medial aspect of the calf. These two fascia fuse at the boundaries of the compartment. The long saphenous vein adventitia is anchored to both fasciase by thick connective tissue strands. Conclusion: The anatomical relationship between the long saphenous vein and the connective framework of the hypodermis suggests that: (1) only the vein running within the deep compartment of the hypodermis should be considered as the ‘true’ long saphenous vein; (2) the other subcutaneous veins running outside the compartment should be considered as collaterals of the long saphenous vein; (3) the connective sheath surrounding the long saphenous vein could oppose dilatation of this vessel should valvular incompetence develop; and (4) thigh muscle contraction could modify the calibre of the long saphenous vein as happens in the deep veins. Finally, the authors propose to term the deep compartment of the medial thigh and the leg hypodermis the ‘long saphenous vein compartment’ and consequently the hypodermic connective lamina, by which it is superficially delimited, as the ‘long saphenous vein fascia’.

The caliber of the human long saphenous vein and its congenital variations

The purpose of the present study is to evaluate the caliber of the normal human long saphenous vein (LSV) in order to verify the occurrence of congenital narrowings. The LSV morphology was evaluated by the dissection of 32 cadaveric limbs, and by ultrasonography of 102 healthy living subjects. The LSV caliber was constant in most of the limbs, showing only a mild and progressive increase from the ankle to the groin. Furthermore, great individual variation in LSV caliber was found. A segmental narrowing of the LSV was present in 39.8% of limbs. The narrow segment was visible with the naked eye during dissection or by ultrasonography in 22.4% of cases (LSV hypoplasia). In the remaining 17.4% the caliber was so reduced that it could only be detected microscopically (LSV aplasia). In relation to the narrow segments, the main ascending flow was shunted in a collateral vein running within the superficial hypodermis. The narrow segments of the LSV had a weaker and less muscular wall than did those of normal caliber. Hypoplasia and aplasia of the LSV are probably due to segmental failure in the development of the vessel, and represent a risk factor for varicosis. In fact, the ascending flow is shunted from the LSV in a collateral vein that runs in the yielding superficial fatty layer of the hypodermis. Furthermore, the high incidence of LSV segmental hypoplasia and aplasia has also to be considered whenever this vein is used as an arterial graft, because of the marked anatomical remodelling.

ECHOANATOMICAL PATTERNS OF THE LONG SAPHENOUS VEIN IN PATIENTS WITH PRIMARY VARICES AND IN HEALTHY SUBJECTS

Objective: To evaluate the pathway of reflux in incompetent long saphenous veins (LSVs), paying particular attention to the role of longitudinal saphenous tributaries in the thigh (accessory saphenous veins, ASVs). Design: Prospective study in a group of patients with primary varices. Comparison with the anatomical patterns in a group of normal subjects. Setting: Private phlebology practice. Patients: Sixty-seven patients with primary varices (100 limbs) and 66 subjects without varices and with competent saphenous veins (120 limbs). Methods: Duplex ultrasound evaluation of the saphenous system in the thigh of patients and healthy subjects. The ‘eye’ ultrasonographic sign was used as the marker to distinguish the LSV from the longitudinal tributary veins of the thigh. Results: In 57% of limbs in patients with varices, reflux followed the saphenous vein, while in 43% the reflux spilled outside the LSV into an ASV (h or S types). When reflux followed the saphenous vein, no large calibre ASVs could be observed. In 30% of limbs in control subjects a parallel tributary vein with a similar calibre was found joining the LSV. Conclusion: Clinically visible varices in the thigh rarely comprise the LSV itself, but are usually dilated ASVs, the reflux stream passing from the proximal LSV into a more superficial ASV. The distal LSV running parallel beneath is often competent. In subjects with healthy LSVs, a large competent tributary vein is already present in the thigh in 30% of cases. This suggests that superficial deviation of reflux flow into an ASV in patients with varices may not arise from haemodynamically acquired changes, but could have a congenital origin. This could even be a predisposing factor in the development of varices.

Stroke following endovenous laser treatment of varicose veins

This report describes an ischemic stroke following endovenous laser treatment of the great saphenous vein in a patient with a patent foramen ovale. No thrombophilic conditions or other possible sources of emboli could be demonstrated.

The saphenous venous compartments

The relationships between the connective framework of the lower extremity hypodermis and the saphenous veins was studied by dissection, stereomicroscopy, ultrasonography and histology in 64 lower limbs. A fibroelastic lamina was evidenced in the hypodermis of the medial aspect of the thigh and leg and in the back face of the leg. This lamina, together with the underlying muscular fascia, fixed the boundaries of two compartments occupied by the saphenous veins and nerves. The adventitia of the saphenous veins was connected to the compartment walls by thick connective strands. The saphenous veins ran deeply in the hypodermis, closely ensheathed by a fibroelastic sleeve. As a consequence, they could no longer be considered as a truly superficial vein. This term seems to be appropriate only for their tributaries, which ran in a more superficial plane just below the dermis. The role of the saphenous vessels in blood return from the lower limbs may be greater than classically accepted. In fact, due to their close fascial ensheathing and adventitial anchoring, muscular contractions may enhance blood flow within these vessels as occurs in the intermuscular veins. Finally, dilative pathology of the saphenous vein may be resisted by the membranous lamina as a sort of a fibroelastic shield.

DOES A DOUBLE LONG SAPHENOUS VEIN EXIST

Background: The incidence of reduplication of the long saphenous vein (LSV) reported in the literature is highly variable, perhaps due to the lack of a clear definition. Objective: To use ultrasonography to re-evaluate the incidence of LSV reduplication in healthy subjects and Patients with varicose veins on the basis of a new definition of this anatomical aspect. Methods: The presence of two parallel superficial venous channels in the lower limb was sought in a series of 610 duplex ultrasound examinations. The LSV was identified, by the ‘eye’ sign, running deeply in the hypodermis, closely ensheathed by two hyperechogenic laminae (the saphenous compartment). Tributary veins were identified by their more superficial course, lying outside the compartment. True LSV reduplication was considered to be present when two venous channels were Present within the saphenous compartment. Results: True reduplication of the LSV is extremely rare (1%) and only affects a segment of vein. Large tributaries running parallel to the LSV do not comprise true reduplication, but may act as a ‘functional double vein’. Better understanding of the anatomy of the LSV may improve operative treatment for varicose veins and improve the use of saphenous veins as arterial grafts.

Skin Iron Deposition Characterises Lipodermatosclerosis and Leg Ulcer

BACKGROUND It is commonly reported that chronic venous disease (CVD) increases the skin iron content in which the excess is stored as haemosiderin. Despite increasing interest in the role of haemosiderin in venous ulceration, no study has systematically evaluated the occurrence of iron overload in the limbs of patients with CVD. PURPOSE To evaluate skin haemosiderin deposition in relation to the presence and severity of skin changes in CVD legs designated according to the clinical, etiologic, anatomic and pathophysiologic (CEAP) classification. METHODS A total of 85 skin biopsies were taken from the medial aspect of 49 limbs with CVD of CEAP clinical stages C2, C3, C4 and C6. The content of ferric ions was assessed by Perls Prussian Blue (PPB) stain. RESULTS No haemosiderin deposition was found in normal skin of C2, C3 and C4A legs, in less severe regions of pigmentation and in some parts of more severely affected limbs. Haemosiderin was always present in lipodermatosclerotic skin and ulcers. Occasionally, haemosiderin was found in the apparently normal perilesional skin of C4b and C6 legs. The regenerating dermis at the base of healing ulcers showed none or light haemosiderin deposition. CONCLUSION Iron overload is not present in the less severe stages of skin damage due to CVD but lipodermatosclerosis and leg ulcers are always accompanied by haemosiderin deposition. In fact, no severe skin changes occur in CVD legs until iron overload occurs. Our results are in agreement with previous reports suggesting that a genetic inability to counteract skin iron overload is present in these patients. A more detailed analysis of disordered iron metabolism should be undertaken in CVD patients.

Topographical Structural Variations of the Human Long Saphenous Vein and its Age-Related Remodelling as Revealed by Correlated Light and Scanning Electron Microscopy

Objective: To study topographical variations of the healthy human long saphenous vein structure and its age-related changes. Methods: One hundred and forty-four specimens taken at different levels from 36 long saphenous veins were studied by correlated light microscopy and scanning electron microscopy. Results: Continuous remodelling occurs in the wall of the long saphenous vein during the progress of life. In young subjects, the intima was narrow, circular muscular cells were present only in the media, and a rich elastic framework was evident in all the three tunicae. A progressive increase in collagen content and longitudinal musculature accompanied by a reduction in elastic tissue was observed in relation to ageing. Furthermore, at all ages, the saphenous vein wall thickened in its caudal portion due to a greater cellular proliferation and deposit of extracellular matrix. Conclusions: The topographical variations in saphenous wall structure as well as its age-related remodelling likely represent the parietal reaction to the physiological hydrostatic load related to the vertical pasture.