Anatomical study of the venous drainage architecture of the scapular skin and subcutaneous tissue.

Venous anatomy of the skin and subcutaneous adipofascial tissue in the scapular region was examined in 14 specimens of 12 fresh cadavers that had been injected systemically with contrast medium. Three-dimensional analysis was performed by radiographing the specimens stereoscopically and splitting them into the skin and subcutaneous adipofascial tissue layers. From the architecture, most of the venous blood that had perfused the dermis was considered to pool in a polygonal venous network, located in the skin layer; to flow chiefly through some large communicating veins; and to enter the scapular, parascapular, or circumflex scapular veins. Most of the venous blood that had perfused the subcutaneous adipofascial tissue was considered to enter the scapular or parascapular veins directly.     

Biostatistical study on the arrangement of the superficial veins of the cubital fossa in Iraqis

A study of the arrangement of the superficial veins of the cubital fossa was made on 300 students and staff of the Military Medical College and the AlMustansiriya College of Medicine. Six types of variations of arrangement of the veins were found, two of which have not been mentioned before. The commonest type was that the median vein of the forearm divides in the cubital fossa into 2 veins, one of which joins the basilic vein, and the other the cephalic vein, although in a few cases this joining (or arrangement), occurred above the cubital fossa. The arrangements which have not been mentioned before were that the communication between basilic and cephalic veins was through a horizontal venous connection between 1 of the tributaries of these 2 veins and the basilic vein, and that the median vein of the forearm divides into median cephalic and median basilic, and a vein from the front of the forearm drains into the median basilic vein.     

Venous drainage architecture of the temporal and parietal regions: anatomy of the superficial temporal artery and vein

Anatomy of the superficial temporal artery and vein was analyzed with arteriograms, venograms, and arteriovenograms of fresh cadavers that had been injected with contrast medium. The superficial temporal artery always divided into two major branches: the frontal and parietal branches. However, the superficial temporal vein divided into one, two, or three major branches. The distribution area of the major branches of the superficial temporal vein was larger than that of major branches of the superficial temporal artery, and arteriovenograms clearly demonstrated that, except for its proximal portion, the superficial temporal vein was independent of the superficial temporal artery. The frontal and parietal branches of the superficial temporal artery had thin venae comitantes that originated from the proximal portion of the superficial temporal vein, and the venae comitantes gave off branches toward the skin and the underlying soft tissue. Branches to the skin anastomosed with a superficial venous network in the skin layer, which was formed by ramifications of the superficial temporal vein. The venous architecture of the temporal and parietal regions consisted of cutaneous veins and venae comitantes and was basically similar to that of the forearm and scapular region.     

The forearm flap

We present our experimental and clinical experiences with the free neurovascular forearm flap. The flap is based on the radial artery, one of the great veins of the forearm (cephalic, basilic, or interconnecting vein), and one or two cutaneous forearm nerves (ulnar, median, or lateral). Because of the standard anatomy, the large caliber of blood vessels, the good sensory supply, the quality and quantity of the forearm skin, and the thin layer of subcutaneous fat, the free forearm flap is a technically easy and safe flap for reconstruction of soft-tissue defects, especially those in the head and neck and those areas of the extremities where sensitive skin is desired.     

The venous skin graft method for repairing skin defects of the fingers

A venous skin graft for the treatment of skin defects in a finger is described. This procedure involves taking a flap from the forearm together with the subcutaneous vein and anastomosing both ends of this vein to the digital artery and vein, respectively. Thirteen difficult finger wounds were resurfaced with such a venous skin graft. The sizes of the flaps ranged from 1.3 X 3.0 cm to 2 X 5 cm. The lengths of the veins taken were from 6 to 12 cm. Subcutaneous fat is thin, and there is good elasticity in the grafted flap.     

Venous congestion and blood flow in free transverse rectus abdominis myocutaneous and deep inferior epigastric perforator flaps

A series of 240 deep inferior epigastric perforator (DIEP) flaps and 271 free transverse rectus abdominis myocutaneous (TRAM) flaps from two institutions was reviewed to determine the incidence of diffuse venous insufficiency that threatened flap survival and required a microvascular anastomosis to drain the superficial inferior epigastric vein. This problem occurred in five DIEP flaps and did not occur in any of the free TRAM flaps. In each of these cases, the presence of a superficial inferior epigastric vein that was larger than usual was noted. It is therefore suggested that if an unusually large superficial inferior epigastric vein is noted when a DIEP flap is elevated, the vein should be preserved for possible use in flap salvage. Anatomical studies with Microfil injections of the superficial venous system of the DIEP or TRAM flap were also performed in 15 cadaver and 3 abdominoplasty specimens to help determine why venous circulation (and flap survival) in zone IV of the flaps is so variable. Large lateral branches crossing the midline were found in only 18 percent of cases, whereas 45 percent had indirect connections through a deeper network of smaller veins and 36 percent had no demonstrable crossing branches at all. This absence of crossing branches in many patients may explain why survival of the zone IV portion of such flaps is so variable and unpredictable.     

Free anterolateral thigh adipofascial perforator flap

The anterolateral thigh adipofascial flap is a vascularized flap prepared from the adipofascial layer of the anterolateral thigh region. It is a perforator flap based on septocutaneous or musculocutaneous perforators of the lateral circumflex femoral system. With methods similar to those used for the free anterolateral thigh flap, only the deep fascia of the anterolateral thigh and a 2-mm-thick to 3-mm-thick layer of subcutaneous fatty tissue above the fascia were harvested. In 11 cases, this flap (length, 5 to 11 cm; width, 4 to 8 cm) was used for successful reconstruction of extremity defects. Split-thickness skin grafts were used to immediately resurface the adipofascial flaps for eight patients, and delayed skin grafting was performed for the other three patients. The advantage of the anterolateral thigh adipofascial flap is its ability to provide vascularized, thin, pliable, gliding coverage. In addition, the donor-site defect can be closed directly. Other advantages of this flap, such as safe elevation, a long wide vascular pedicle, a large flap territory, and flow-through properties that allow simultaneous reconstruction of major-vessel and soft-tissue defects, are the same as for the conventional anterolateral thigh flap. The main disadvantage of this procedure is the need for a skin graft, with the possible complications of subsequent skin graft loss or hyperpigmentation.     

Venous drainage in the reverse forearm flap

Venograms were performed in three cases of reverse forearm flap. The "crossover pattern" of the communicating branches between the two venae comitantes and the "bypass pattern" of the collateral branches of each vein have been demonstrated. These factors may explain the reverse drainage of venous blood, even though the valves of the vein are intact. Notably, the cephalic vein also shows a good communication with the deep venous system. Thus it can contribute another route for venous drainage in this flap.     

Alternative venous outflow vessels in microvascular breast reconstruction

The lack of adequate recipient vessels often complicates microvascular breast reconstruction in patients who have previously undergone mastectomy and irradiation. In addition, significant size mismatch, particularly in the outflow veins, is an important contributor to vessel thrombosis and flap failure. The purpose of this study was to review the authors' experience with alternative venous outflow vessels for microvascular breast reconstruction. In a retrospective analysis of 1278 microvascular breast reconstructions performed over a 10-year period, the authors identified all patients in whom the external jugular or cephalic veins were used as the outflow vessels. Patient demographics, flap choice, the reasons for the use of alternative venous drainage vessels, and the incidence of microsurgical complications were analyzed. The external jugular was used in 23 flaps performed in procedures with 22 patients. The superior gluteal and transverse rectus abdominis musculocutaneous (TRAM) flaps were used in the majority of the cases in which the external jugular vein was used (72 percent gluteal, 20 percent TRAM flap). The need for alternative venous outflow vessels was usually due to a significant vessel size mismatch between the superior gluteal and internal mammary veins (74 percent). For three of the external jugular vein flaps (13 percent), the vein was used for salvage after the primary draining vein thrombosed, and two of three flaps in these cases were eventually salvaged. In three patients, the external jugular vein thrombosed, resulting in two flap losses, while the third was salvaged using the cephalic vein. A total of two flaps were lost in the external jugular vein group. The cephalic vein was used in 11 flaps (TRAM, 64.3 percent; superior gluteal, 35.7 percent) performed in 11 patients. In five patients (54.5 percent), the cephalic vein was used to salvage a flap after the primary draining vein thrombosed; the procedure was successful in four cases. In three patients, the cephalic vein thrombosed, resulting in two flap losses. One patient suffered a thrombosis after the cephalic vein was used to salvage a flap in which the external jugular vein was initially used, leading to flap loss, while a second patient experienced cephalic vein thrombosis on postoperative day 7 while carrying a heavy package. There was only one minor complication attributable to the harvest of the external jugular or cephalic vein (small neck hematoma that was aspirated), and the resultant scars were excellent. The external jugular and cephalic veins are important ancillary veins available for microvascular breast reconstruction. The dissection of these vessels is straightforward, and their use is well tolerated and highly successful.     

Thermoregulatory anatomy of pronghorn (Antilocapra americana)

We have found that pronghorn (Antilocapra americana) use external heat exchange with the environment and internal heat exchange between the carotid artery rete and cavernous venous sinus blood to regulate body temperature. Now we have investigated the relationship between the histological structure of the skin, cephalic veins, and carotid rete–cavernous sinus system and the physiological mechanisms pronghorn use, and whether their thermoregulatory anatomy has adaptive advantages. We harvested tissue samples of skin, three veins (i.e., angularis oculi vein, dorsal nasal vein, and facial vein), and the carotid rete–cavernous sinus system from four pronghorn, two culled in summer and two in winter, and examined each histologically. The three veins had the typical structure of veins with large lumina and thin walls. The carotid rete consisted of small (0.1–0.5 mm) arterioles with a density of ~10/mm², intertwined with veins (~2/mm²), enclosed within the cavernous sinus; a structure ideal for heat exchange. We concluded that the main function of the dorsal nasal and facial veins is to return cold blood to the body to effect whole body cooling. The cavernous sinus is supplied with warm blood by the palatine veins in winter and cold blood by the deep facial veins in summer, an arrangement different to that in other ungulates, such as sheep, in which the angularis oculi vein supplies the cavernous sinus. Pronghorn skin is richly supplied with blood vessels that facilitate convective heat loss in summer. In winter, the number of coarse and fine hairs per square millimeter increases more than in European deer to form a thick pelage that minimizes heat loss. In summer, the pelage is shed because hair follicles involute. Unlike in other ungulates, pronghorn skin has little adipose tissue. The number of apocrine glands increases in winter rather than in summer. We concluded that the glands have a reproductive/social function rather than a thermoregulatory one. In summary, our study shows that the thermoregulatory anatomy is consistent with our physiological data and has adaptive advantages that help explain the survival of pronghorn in an arid habitat characterized by extreme temperature variation and sparse vegetation.     

Cholinergic innervation of the human pulmonary circulation

The cholinergic innervation of the pulmonary circulation was studied in man. Both extra- and intrapulmonary branches of the pulmonary artery and vein are provided with a cholinergic of the vein. In the main branches of the pulmonary vessels, the existence of two nerve plexuses, a superficial and a deep one, was observed. The superficial plexus is localized in the outer adventitial layer while the deeper plexus is localized in the adventitial-medial transitional zone. In smaller arteries and veins, the existence of a single plexus (adventitial-medial) was observed. In some specimens, the presence of diffuse masses of acetylcholinesterase (AChE)-positive material or elbow-shaped AChE-positive formations was observed. The nature of these formations as well as the possible functional role of a cholinergic system in the pulmonary circulation are discussed.     

Psychogenic and neurogenic effects on the intact forearm vein of man.

By means of an elegant venous preparation the behavior of intact veins of man can be studied decisively. The superficial veins of man are extremely sensitive to the environment and the autonomic and central nervous systems. This report illustrates the response of an isolated venous segment of the forearm to various psychogenic and neurogenic stimuli, with change in tone of the smooth muscle of the venous segment being reflected by change in segmental venous pressure. It is shown that the superficial forearm veins can be conditioned and that they are extremely dynamic and certainly not passive conduits for returning blood to the heart.     

Venous Distensibility in Patients with Varicose Veins

Forearm veins were studied to determine whether patients with primary varicosity of the saphenous veins had a generalized abnormality of the venous system. Distensibility of the superficial forearm and hand veins was measured in 25 patients with varicosity of the saphenous veins, and in 25 control subjects. Patients with saphenous varicosity had a significantly greater distensibility of the undistorted forearm veins than control subjects. Hysteresis of distensibility curves was more prnounced in patients with varicosity than in control subjects; mean hysteresis index was 0.65 ± 0.06 versus 0.28 ± 0.02 in controls. These investigations suggest that an increased distensibility of the venous system is the predisposing factor in the development of varicose veins.     

Anatomy of the veins of the head in the domestic fowl

The anatomy of the cephalic venous system in the fowl was studied in 19 specimens by means of latex-injected preparations and by dissection. The brain sinuses converge dorsally upon the large cervical sinus and vertebral veins. Dorso-ventral communication is provided by the occipital veins posteriorly, while the ophthalmic system unites both dorsal and ventral sinuses and the temporal rete with the extracranial veins anteriorly. The jugular veins are formed from the superficial branches of the facial veins and serve mainly as outlets for extracranial blood. They are united at the base of the head by a prominent transverse anastomosis which slopes caudally towards the larger, right jugular. As in mammals, the carotid veins envelop the internal carotid arteries and anteriorly form a bulbous sinus cavernosus around the inter-carotid anastomosis.     

Duplex-Doppler ultrasonography in the detection of lower extremities deep venous thrombosis and in the detection of alternative findings

The diagnoses observed in patients referred for the Doppler ultrasonographic examination of peripheral and iliac veins for suspected deep venous thrombosis (DVT) are presented in this study. During 48 months 2,610 patients were examined by duplex Doppler ultrasonography (US). Among these, 1,879 were women (72%) and 731 men (28%), with the age-range 16-91 (mean 56, 2) years. Ultrasonic scanners Acuson 128 XP 10, ATL HDI 5000, GE Logiq 7, and GE Logiq 9 were used, with transducers in the frequency range from 2.5-14 MHz. Findings were categorized into four main categories: (1) deep venous thrombosis (DVT); (2) pathology predominantly related to superficial veins without DVT, (3) pathology of adjacent structures; (4) normal findings. 562 patients had DVT (21.5%). 1,108 patients (42.5%) had predominant pathology of superficial veins: postthrombotic syndrome, superficial thrombophlebitis and varicose veins. 390 patients (14.9%) had pathology of surrounding structures, unrelated to veins, the most common pathology being popliteal cysts and muscular hematomas. These lesions must be properly diagnosed by US to avoid erroneous anticoagulant treatment.     

The venous communication between the gastrocnemius muscle heads

This investigation establishes the venous communication between the gastrocnemius muscle heads. Fourteen fresh (with the exception of one) cadaveric specimens were examined. Anastomotic veins were dissected along the raphe after perfusion of each muscle with 0.1 % methylene blue solution. A distally based musculocutaneous perforating vein of the medial head was the site of perfusion in 13 specimens, whereas one specimen received injection through the accompanying vein of the medial sural cutaneous nerve. Additional perfusion of dye from different sites was required in two specimens. Communicating veins were dissected in all 14 muscles. Direct anastomotic veins were detected in eight specimens; whereas in six the accompanying vein of the medial sural cutaneous nerve that had been included proved to be the intermediate pathway of venous communication between the muscle heads. Obstructive valves were encountered in most cases; nevertheless anastomotic veins were always recognized. The role of valves and the clinical implications are discussed.     

Orbital venous anatomy of the rat

Ten rats were embalmed, the veins of the head latex-injected, and the heads were dissected. Five rats were used to prepare corrosion casts of the venous structures of the head. It was found that the rat has an orbital venous plexus rather than an orbital venous sinus as seen in the mouse and hamster. The orbital venous plexus was formed by the external dorsal ophthalmic vein, the external ventral ophthalmic vein and numerous anastomoses between these veins. Of major interest was a large anastomotic vein located in the caudaldorsal area of the orbit. The anastomotic vein joined the orbital venous plexus and the superficial temporal vein.     

Effectiveness of long term oral anticoagulation treatment in preventing venous thrombosis in hereditary protein S deficiency.

In eight of 14 patients who were deficient in protein S and who belonged to two unrelated families thrombosis presented as thrombophlebitis in seven and deep vein thrombosis in six, complicated by pulmonary embolism in four and leg ulcers in two. In four patients superficial thrombophlebitis preceded deep vein thrombosis by one to 11 years. Post-thrombotic varicose veins and venous insufficiency had developed in four patients. In three of those and in a fourth patient symptomatic superficial thrombophlebitis, deep vein thrombosis, and pulmonary embolism did not recur while they were taking oral anticoagulant treatment for six to 12 years. The anticoagulation intensity corresponded to international normalised ratio values of over 2.5. It is concluded that the benefits of anticoagulant treatment for patients with congenital thrombotic disease are great, and thus it is necessary to make an early diagnosis and treat patients at risk of developing thrombosis.