Terminal Valve Research Articles

Research on the Variable Static Pressure Control Used Iterative Algorithm in a VAV System

In a VAV system the static pressure can be reseted based on the change of load. At low load conditions the duct static pressure can be adjusted lower, that make VAV terminal air valves in large opening as far as possible.And lower fan outlet pressure can effectively reduce fan energy consumption. This paper presents a method using iterative algorithm to control the fan frequency. It can improve the dynamic quality of the control system. Satisfying the requirements under lower static pressure so as to achieve the purpose of energy-saving.

The ostial valve of the great saphenous vein

Venous valves have been classified into parietal (PVs) and ostial valves (OVs). PVs are located within the lumen of veins, whereas the OVs are located directly at the confluence of two veins. In the common femoral vein (CFV), the most prominent PVs are the suprasaphenic and infrasaphenic valve. The terminal valve (often designated as 'valvule ostiale' in the relevant literature in French) defined as that lying between the orifice of the great saphenous vein (GSV) and the most proximal of the major superficial tributary veins and the preterminal valve represent the most important PVs in the GSV. While PVs are well studied, there is not much literature on the OVs of the superficial venous system, especially of the GSV. In order to investigate the presence of OVs (defined strictly as valves located at the entrance of a tributary vein) in the GSV, we carried out studies on specimens obtained from bodies bequested to the Division of Clinical and Functional Anatomy of Innsbruck Medical University. Ninety-eight specimens consisting of the CFV and the attached tributary veins including the GSV were investigated. In five of these (5.1%), a single-cusped OV, in six (6.1%) a two-cusped OV and in 10 (10.2%) remnants of an OV were identified. Thus, OVs do not seem to be primarily present in all GSVs. The distinction between PVs and OVs is not always clear in literature, and as a consequence misinterpretations may occur. Very often the terminal valve of the GSV, which is in fact a PV, is designated as an 'ostial valve'. In view of its widespread use, we suggest that the term 'ostial valve' together with its clear description be included in the consensus documents of the 'Union Internationale de Phlébologie'.

Position of valves within the subclavian and axillary veins

The aim of this explorative morphologic study was to determine the position and frequency of the valves in the axillary and subclavian veins. The position and frequency of the valves in the subclavian and axillary veins were studied macroscopically in 59 limbs from 30 cadavers. We measured in situ with a measuring tape, starting from the venous angle toward the initiation of the axillary vein. All cadavers were bequeathed by informed consent. A terminal valve existed in all subclavian veins within the range of 0.0 to 27.5 mm (mean: left, 13.87 mm; right, 9.78 mm) distally to the venous angle; a second valve existed in one left and one right subclavian vein at a distance of 30.0 and 30.5 mm, respectively. All left axillary veins had a "most proximal" valve (mean, 103.4 mm), 73.3% also possessed a second valve (mean, 140.48 mm), and 16.7% had a third valve (mean, 153.9 mm). All right axillary veins possessed at least one valve (mean, 100.07 mm), 75.86% had a second valve (mean, 134.55 mm), 34.48% also had a third valve (mean, 157.30 mm), and 10.3% had a fourth valve (mean, 140.0 mm). All of the axillary and subclavian veins in our specimens possessed at least one valve. All the valves in the subclavian veins were concentrated to the proximal half, resulting in a valveless distal half. The subclavian vein rarely had a second valve. The valves in the axillary veins were located in the distal half, resulting in a valveless proximal half. The axillary vein can have one to four valves. No relation was evident between the frequency of the valves and the age of the donors when they died. Many other factors may influence the frequency of the valves in the axillary vein.

Morphology and taxonomy of the planktonic diatom Chaetoceros species (Bacillariophyceae) with special intercalary setae in Korean coastal waters

Species of the diatom genus Chaetoceros with special intercalary setae are uncommon. For this study, we collected Chaetoceros species from August 2008 to September 2009 in Korean coastal waters and examined the ultra structures of the Chaetoceros species C. coarctatus, C. compressus var. hirtisetus, C. contortus, C. diversus, and C. messanensis, using light and scanning electron microscopy. C. coarctatus, in the subgenus Phaeoceros, showed longer and stronger spines than those found in other species. C. coarctatus and C. diversus had special intercalary setae with spines in straight arrangements, whereas C. compressus var. hirtisetus, C. contortus, and C. messanensis had special intercalary setae with spines arranged in spirals. The setae of C. coarctatus had spines that were robust toward the tips and, overall, longer and stronger than were those of other species. C. coarctatus and C. diversus were straight, and C. compressus var. hirtisetus, C. contortus, and C. messanensis spiraled. C. messanensis had two types of special intercalary setae, both forked: 1 with spines in spirals and 1 lacking spines. We did not find spines on the anterior part of divergent point of the special intercalary setae of C. messanensis. Foramina shapes of these 5 Chaetoceros species varied as follows: very small or no foramina in C. coarctatus, relatively wide and slightly centrally constricted foramina in C. compressus var. hirtisetus and C. contortus, quite narrowly slitted or no foramina in C. diversus, and lanceolate or hexagonal foramina in C. messanensis. We found rimoportula in both intercalary and terminal valves of C. coarctatus, but C. compressus var. hirtisetus, C. contortus, C. diversus, and C. messanensis only had rimoportula in terminal valves. In addition, C. compressus var. hirtisetus and C. contortus were new to Korean coastal waters.

The role of circumflex femoral veins in the saphenofemoral junction incompetence: a case report

A 31 year-old female patient, an opera singer, came for a consultation, mainly for aesthetic problems of the lower limbs. An asymptomatic bilateral P-point pelvic shunt was demonstrated by the EchoDoppler, while no nutcracker syndrome was detected. The examination demonstrated a medial circumflex femoral vein (MCFV), going into the common femoral vein and then into the great saphenous vein (GSV). The Valsalva manoeuvre showed the GSV terminal valve incompetence. A dilated MCFV vein at the level of the saphenofemoral junction was the source of the reflux through the GSV, while the external iliac vein was competent. GSV reflux with Valsalva was present only in the lying position. Flow in the MCFV was directed toward the CFV during and after the Valsalva. The examination shows clearly that a GSV reflux can sometimes occur in absence of iliac reflux. Circumflex femoral veins (medial and lateral) are anatomical variations, but common findings during ordinary EchoColourDoppler investigations of the venous system of the lower limbs.

A duodenal follicular lymphoma associated with the lesion mimicking MALT lymphoma in terminal ileum and Bauhin valve

This is a case report of a 66-year-old woman who consulted us with a 1-week history of postprandial epigastric discomfort and dyspepsia. Upper and lower gastrointestinal endoscopy and double-balloon enteroscopy revealed lesions in three parts: a swelling with a shallow depression in the ampulla of Vater, flat and rough nodules in the jejunum, and a mixture of lymphoid polyposis and rough surface of follicular lymphoma of the terminal ileum and Bauhin valve. The histological, immunophenotypic, and molecular findings of the duodenal lesion confirmed the diagnosis of follicular lymphoma. We initially diagnosed the ileal lesion as MALT lymphoma immunohistochemically. However, Southern blot hybridization analysis for immunoglobulin heavy chain gene rearrangement showed identical monoclonal bands in both the duodenal and ileal lesions. The molecular cytogenetic studies were also positive for the 14;18 translocation in both lesions. Therefore, the true diagnosis of this ileal lesion should be a follicular lymphoma with marginal zone differentiation. Primary follicular lymphomas of gastrointestinal tract were suggested to have intermediate features between nodal follicular lymphoma and MALT lymphoma. This case is an important clue to prove the similarity of follicular lymphoma of gastrointestinal tract to MALT lymphoma and will be crucial in considering the therapeutic strategy.

Development of Primary Superficial Venous Insufficiency: The Ascending Theory. Observational and Hemodynamic Data From a 9-Year Experience

Hemodynamic principles suggest that primary venous insufficiency follows the hydrostatic column of venous pressure of the limbs, and therefore, venous reflux begins at the lower points and rises upwards. To test the hypothesis of an "ascending development" of reflux, we carried an observational study to analyze the natural evolution of lower limb venous insufficiency. During 9-year period patients with primary superficial venous disease who refused treatment were followed prospectively with 6-month scheduled clinical and duplex ultrasound examinations. Localization, stage, and evolution of the venous patterns were compared. A total of 104 limbs in 99 patients were analyzed (12 males, 92 female; mean age 48.7 years). Prevalence of reflux was (p < 0.001) more frequent along great-saphenous and its tributaries (78/104, 75%) than nonsaphenous veins. The time of re-examination ranged from 1 to 13 years (mean 4 +/- 3.1 years). With the exception of six remaining stable, all the veins showed a progression of insufficiency (94%); 47 involved deep circulation. In all the worsened refluxes, an extension to reach one or more venous segments at an upper level, uninvolved before, was found. There was no downward oriented pattern of progression. There was no significant difference in age, gender, and type of vein between the stable and progressive diseases. Natural history of primary venous insufficiency is that of a progressive disease, which begins at lower levels of the limbs and develops in an antegrade manner as venous stasis is higher where force of gravity is higher. This data do not support the aggressive and widespread treatment of terminal valve as first approach, but need to be supported by larger studies.

Morphology and ecology of the diatom Chaetoceros vixvisibilis (Chaetocerotales, Bacillariophyceae) from the Adriatic Sea

The chain-forming diatom Chaetoceros vixvisibilis is one of the most abundant and frequent diatoms in the northeastern Adriatic Sea. This species had not been previously studied by electron microscopy. Its general morphology is similar to those species allocated in the subgenus Hyalochaete: cells and chains (straight, of variable length, usually 4-8 cells per chain, but can be longer) of delicate appearance, valves thinly silicified, with slightly eccentric annulus and costae radiating from it, a single rimoportula present only at terminal valves, long, thin and delicate setae perforated by tiny poroids with no spines, and one plate-like chloroplast per cell. Setae with no spines are not common among members of Hyalochaete (and the whole genus Chaetoceros), except C. socialis. The most characteristic feature is, however, the resting spores commonly found, which also show morphological variability, from solitary to paired, both valves convex to domed and surface smooth or with small granules, and one to four strong spines often branching dichotomically. Abundances of C. vixvisibilis are positively correlated to the Po River inflow. Maximum abundances (> 10 6 cells L -1 ) were found in the period April-July, in the temperature range between 12 and 16°C, salinity between 33 and 38, when total phosphorus concentration is higher than 0.4 μmol L -1 , but occasionally also in nitrogen limited conditions.

Great saphenous varicose vein surgery without saphenofemoral junction disconnection

The aim of this case-control study was to determine whether preoperative duplex imaging could predict the outcome of varicose vein surgery without saphenofemoral junction (SFJ) disconnection. The duplex protocol included a reflux elimination test (RET) and assessment of the competence of the terminal valve of the femoral vein. One hundred patients with chronic venous disease who had a positive RET result and an incompetent terminal valve were compared with 100 patients matched for age, sex, clinical class (Clinical Etiologic Anatomic Pathophysiologic (CEAP) class C2-C6) and disease duration, but who had a positive RET result and a competent terminal valve. All patients underwent ligation and proximal avulsion of the incompetent tributaries from the great saphenous vein trunk without SFJ disconnection. Clinical and duplex follow-up lasted for 3 years, and included Hobbs' clinical score. Of legs with a competent terminal valve, 100 per cent were rated as cured (Hobbs' class A or B) and 14.0 per cent developed recurrent varices. Patients with an incompetent terminal valve had significantly worse results: 29.0 per cent had Hobbs' class A or B and 82.0 per cent developed recurrence (P < 0.001). Preoperative duplex assessment of the terminal valve could be used to identify patients suitable for varicose vein surgery without the need for SFJ disconnection.

The anatomy of the small saphenous vein: Fascial and neural relations, saphenofemoral junction, and valves

Varicose veins are a frequent burden, also in the small saphenous system. Yet its basic anatomy is not described consistently. We therefore investigated the fascial and neural relationships of the small saphenous vein (SSV) as well as the frequency and position of valves and the different junctional patterns, also considering the thigh extension. We dissected the legs of 51 cadavers during the regular dissection course held in winter 2007 at Innsbruck Medical University, with a total of 86 SSVs investigable proximally and 94 SSVs distally. A distinct saphenous fascia is present in 93 of 94 cases. It starts with a mean distance of 5.1 cm (SD 1.2 cm) proximal to the calcaneal tuber, where the tributaries to the SSV join to form a common trunk. The neural topography at the level of the gastrocnemius muscle's origins shows the medial sural cutaneous nerve in 88% medially and in 12% laterally to the SSV, the tibial nerve in 64% medially and in 36% laterally, and the common fibular nerve in 98% medially and in 2% laterally to the vein. The saphenopopliteal junction (SPJ) resembled in about 37% type A (UIP-classification), 15% type B, and 24% type C. A total of 17% of specimens showed a venous web or star at the popliteal fossa and 6% had a doubled junction. A thigh extension could be demonstrated in about 84%. A most proximal valve was present in only 94% at a mean distance of 1.2 cm (SD 1.4 cm) to the SSVs orifice. A consecutive distal valve was only present in 65% with a mean distance of 5.1 cm (SD 2.3 cm). Two fascial points or regions can be described in the SSVs' course and its own saphenous fascia is demonstrated macroscopically in almost all cases. The neural topography is highly individual. The SPJ is highly individual where we found hitherto unclassified patterns in a remarkable number of veins. Venous valves are not as frequent as we supposed them to be. Furthermore, not all most proximal valves seem to be terminal valves.

Venous valves and major superficial tributary veins near the saphenofemoral junction

Venous valves are still discussed controversially, mainly because it is still uncertain whether primarily missing or insufficient valves or the weakness of the venous walls cause varices. Furthermore, the distribution and frequencies of major superficial tributary veins (MSTVs), which should discharge the great saphenous vein (GSV) between the terminal (TV) and preterminal valve (PTV) gain in importance; a fortiori as remaining MSTVs during primary varicose vein treatment may be a reason of future recurrent varicose veins. Therefore, the aim of this study was to investigate both the frequency and position of the GSV valves and the distribution of MSTVs near the saphenofemoral junction (SFJ). We investigated 114 formalin fixed bodies with 217 GSVs. The measurement of the position of the valves and the entrances of the MSTVs was performed in situ from the SFJ to the nodule of the valve or to the orifice of the tributary vein into the GSV, respectively. On average, the specimens possessed 2.26 valves on the left side and 2.07 valves on the right side. First, valves were present in all 217 legs in a range of 0.0 to 7.2 cm. Taking as a basis the strict definition of a TV that it lies between the orifice of the GSV and the most proximal MSTV we could find only 75 TVs (68.8%) on the left side and 77 (71.3%) on the right side. In total, we found 803 MSTVs entering the GSV, an average of 3.7 veins per GSV. The left GSVs had significantly more MSTVs (P = .000). Most frequently, the superficial external pudendal vein (SEPV) existed in 90.3%, joining the GSV from medial 16.9 mm distally to the SFJ. A complete "venous star" of the MSTVs, as it is described in several textbooks, was present in only 18.4%. Terminal and preterminal valves of the GSV do not always exist. Using a strict definition whether a valve should be called either "terminal valve" or "preterminal valve", we will find a lot of them completely missing. This means that in a considerable number of patients reflux from the common femoral vein (CFV) to the GSV and further on into the MSTVs might occur. Several major superficial tributary veins join the GSV within the first millimeters; therefore a thorough exposition and monitoring of these vessels during diagnostic procedures are obviously crucial for a long-lasting success.

Preservation potential of Katharina tunicata and Mopalia muscosa (Mollusca, Polyplacophora) on two rocky shores of San Juan Island, Washington, USA

Taphonomic analyses of modern Katharina tunicata and Mopalia muscosa valves (Mollusca, Polyplacophora) collected from San Juan Island, Washington, USA, demonstrate that preservation potential of chitons varies by species and locality. Damage levels observed in the valves reflect differences in extrinsic environmental conditions, but intrinsic characters affect response of the skeletal material to local processes. Although both are more likely to become fossils at the lower energy site, K. tunicata valves in poor condition are more likely to occur than poor-condition M. muscosa valves at either site. Mopalia muscosa valves are least likely to be preserved at the higher energy site. Katharina tunicata valves appear more resistant to destruction than M. muscosa valves, suggesting that the former are more likely to become fossilized. The preservation potential of the three types of valves (normally one head, six medials, and one tail per individual) differs for both species. Medials are more likely to be preserved than either terminal valve of K. tunicata or M. muscosa. Head valves are least likely to be preserved, but K. tunicata heads are less likely to be preserved than M. muscosa heads. The biases are not due to greater frequency of medials, because valves do not occur in the 3:1 ratio seen in living animals. Divergence from expected ratios and variation in taphonomic condition for all three valve types in modern environments agrees with observations in the fossil record. The rarity of fossil chitons may be due to biases against preservation rather than absence in ancient environments.

Neovascularisation

SummaryThere are different causes of neovascularisation: vascular endothelial growth factor, inflammatory process, hypertrophy of pre-existant vessels (lymph node veins), haematomas revascularisation, and high difference in pressure. The latter 3 depend directly on the way the operation is performed hence on the surgeon.Concerning the primary varices patch saphenoplasty do not abolish neovascularisation. It is of first importance to perform a flush ligation only in case of incontinent terminal and pre-terminal valves. In that case an incision as small as possible must be carried out with minimal dissection and with tumescence to limit the bleeding and hematomas. When the terminal valve is competent it is better to choose endovascular technique.Concerning re-do it is mandatory to avoid useless re-do, the best choice is foam sclerotherapy. I am convinced that neovascularisation are produced by the complications which are induced by a large dissection. The barrier technique are, probably, not as useful as we was told 10 years ago. The lack of aggressiveness during the operation is certainly far more important: “Doing less in the groin to do better for the recurrence and re-recurrence”

Management of recurrent varices at the popliteal fossa after surgical treatment

To analyze prevalence, incidence mechanisms, physiopathology, investigations, treatment techniques and results of recurrent varices at the popliteal fossa after surgery. Published literature was analyzed as personal experience. Recurrent varices after surgery at the popliteal fossa are much less frequent than at the sapheno-femoral junction because the short saphenous vein is less often the site of incompetence and treated by surgery. Precise prevalence and incidence is unknown. An analysis of recurrences at the popliteal fossa revealed three causes: (1) Incomplete division of the sapheno-popliteal junction (SPJ) at the terminal valve, which was incompetent at the initial surgery. The persisting reflux fills tributaries still connected to the saphenous stump; (2) Neovascularization reconnects the popliteal vein to the superficial network with new vessels, which are valveless; (3) Because the initial diagnoses is wrong and the incompetence involves the other veins of the popliteal fossa or arises from pelvic veins, which had not been recognized. Duplex scanning (DS) should identify the various sites of reflux and give precise anatomical and haemodynamic data. Treatment methods after recurrence at the popliteal fossa are repeat surgery, sclerotherapy or pelvic vein embolization when identified as the cause. Results provided by these different methods were analysed. At present, no randomized control has given grade 1A, 1B or 2A, 2B recommendations. We recommend that ultrasound-guided foam sclerotherapy should be the treatment of choice unless DS shows an incompetent stump at the SPJ with a gross reflux filling the venous network.

DIVERSITY IN THE GENUS SKELETONEMA (BACILLARIOPHYCEAE): III. PHYLOGENETIC POSITION AND MORPHOLOGICAL VARIABILITY OF SKELETONEMA COSTATUM AND SKELETONEMA GREVILLEI, WITH THE DESCRIPTION OF SKELETONEMA ARDENS SP. NOV.1

Skeletonema costatum (Grev.) Cleve emend. Zingone et Sarno and S. grevillei Sarno et Zingone were known only from the type material collected from Hong Kong waters more than a century ago. Both species have now been collected as live material, and their morphology and phylogenetic position are investigated in this study. Eight Skeletonema strains isolated from Florida, USA; Uruguay; and Brazil are attributed to S. costatum, while one strain from Oman is ascribed to S. grevillei based on morphological similarity to the type material of these species. In addition, a new Skeletonema species, S. ardens Sarno et Zingone, is described for a strain from Singapore and two from northern Australian waters. Skeletonema ardens has terminal fultoportula processes ending in a tapered, undulate protrusion and long intercalary fultoportulae with 1:1 junctions. The rimoportula of terminal valves is located at the margin of the valve face. No major morphological variations were observed within S. grevillei and S. ardens along a salinity gradient, whereas in S. costatum, the processes shortened and the valves came into close contact at low salinities, as already described for S. subsalsum (Cleve) Bethge. Consistent with their morphology, Skeletonema costatum and Skeletonema subsalsum also had similar rDNA sequences. Skeletonema grevillei and S. ardens were distinct in the large subunit (LSU) phylogeny. Skeletonema ardens exhibited consistent intraspecific genetic differences in both the LSU and small subunit (SSU) rDNA.

Frequency and exact position of valves in the saphenofemoral junction

Summary Background: Varicose veins are common. As venous valves are included in the pathological development of varices they have been studied by many authors. Nonetheless, the exact position of valves is unclear. Material and method: The exact position of the valves in the greater saphenous vein was studied macroscopically from the saphenofemoral junction up to 25 cm distally in situ on 72 cadavers with a total of 140 veins. Results: A terminal valve existed in 88.5% in the range of 0 to 1.4 cm and a preterminal valve was present in 89.2% in the range of 1.4 cm to 8.2 cm distally to the saphenofemoral junction. In about a fifth of the cases a third valve could be identified. Conclusion: Our results suggest, that the recent general agreement that there are always a terminal and a preterminal valve has to be negated.

Récidive de varices à l’aine et à la fosse poplitée après traitement chirurgical

Patients who undergo surgery involving the groin and the popliteal fossa often develop recurrent varices which require careful management. Several surveys using various classification systems have estimated the prevalence of recurrent varices after groin and popliteal surgery. Patients may seek medical care for various reasons: unsightly recurrent varicose veins, vein-related symptoms, appearance of cutaneous or subcutaneous changes, concerns about the health risk related to their veins or limitation of activity. Recurrent varices may also be found at routine follow-up examinations.An analysis of recurrence at this location reveals three main mechanisms–incomplete resection of the saphenofemoral or saphenopopliteal junctions in patients with an initially incompetent terminal valve. The persisting reflux feeds the tributaries connected at the saphenous stump;–the second mechanism is related to neovascularisation that reconnects the deep venous system with the superficial network; the neo-veins are valveless. This phenomenon appears to be more frequent when the resection of the saphenous vein ending has been complete;–the third mechanism is due to a tactical error; the refluxive pelvic veins that had not been diagnosed feed the varices.Duplex scanning identifies the different possible mechanisms and provides anatomical and hemodynamic data. Interventional treatment methods after varices recurrence are redosurgery, sclerotherapy and pelvic vein embolization when they are at issue. All these methods are described in details. Results provided by these treatments are analysed. Unfortunately no randomized control study enables grade A or B recommendations. Personally we suggest that ultrasound guided foam sclerotherapy should be the first-line treatment except when duplex scanning reveals an intact incompetent saphenous stump at the saphenofemoral junction or/and saphenopopliteal junction with a massive reflux filling the varicose network.

DIVERSITY IN THE GENUS SKELETONEMA (BACILLARIOPHYCEAE). I. A REEXAMINATION OF THE TYPE MATERIAL OF S. COSTATUM WITH THE DESCRIPTION OF S. GREVILLEI SP. NOV.1

The type material of Skeletonema costatum (Greville) Cleve was reexamined with the aims of providing an EM description of the species and clarifying which of the recently recognized Skeletonema Greville species, if any, deserves the epithet costatum. Two permanent mounts and two loose samples from the same collections from Hong Kong Bay were examined. Two distinct Skeletonema species were found in all materials. Based on the original description and on the observation of the lectotype, it was concluded that the most abundant morph in the type material is S. costatum. Cells were heavily silicified and 5–16 μm in diameter. The external processes of the fultoportulae in the terminal valves were open tubules with claw‐shaped tips. The intercalary fultoportulae processes were closed flattened tubules with a pore at their base, each attached to two processes of the sibling valve (1:2 junction). The rimoportula had a long process and was located marginally in all valves. The second morph in the type material was described as Skeletonema grevillei Sarno et Zingone sp. nov. Cells were delicate, 4–7.5 μm in diameter, and formed short colonies. The fultoportulae processes in the terminal valves were open tubes having narrow tips with truncated or spiny margins. In the intercalary valves, they formed knuckle‐like generally 1:1 junctions. A scallop‐work of silica bridges joined the bases of the processes. The rimoportula was marginal in all valves. Neither S. costatum nor S. grevillei match any Skeletonema species that have been recently analyzed by combined morphological and molecular approaches.

1603–2003: Four Centuries of Valves

In 1603, just 400 years ago, Hyeronimus Fabricius ab Aquapendente (1533–1619) published the first treatise on the venous valves (VV) entitled De VenarumOstiolis. VV had been already described in the heart and in larger veins but Fabricius was the first meticulously to describe their anatomy in the whole body (Figs. 1 and 2). He also described a test to evaluate VV competence (Fig. 1) that led his student, William Harvey, to discover the circulation of the blood. Fabricius correctly described VV both in deep and superficial veins of the lower limb (Fig. 3). He also affirmed that the terminal portion of the great saphenous vein (GSV), has twin-valves at the orifice, then at two fingers’ distance a further another set of twin-valves: ‘...primum continet bina ostiola; deinde duorum digitorum intervallo alia bina;...’ (Fig. 3). The first is the well known terminal valve situated at the termination of the GSV to prevent reflux from the femoral vein. The more distal one is the pre-terminal valve (PTV) and lies just below the openings of the sapheno-femoral junction (SFJ) tributaries. Surprisingly, following Fabricius’ description of this arrangement, the PTV was not mentioned further until 1995 by Pieri et al. They used duplex ultrasonography to assess its morphology and haemodynamic role. The PTV prevents venous reflux from the tributaries of SFJ into the GSV trunk, while the terminal valve is closed. Incompetence of the PTV is the reason for reflux in the GSV when the terminal valve is still competent. This occurs mainly during pregnancy and in pelvic congestion syndromes, when part of the pelvic blood is drained from the pelvic floor by the external pudendal vein and then channelled to the GSV (Fig. 4). Finally, Fabricius guessed the correlation between VV failure, varicose veins (in which he described bidirectional flow) and venous ulcers (‘incompetent VV cannot prevent accumulation of fecaloid humours to the lower leg that cause ulceration’). In both cases, Fabricius treated varicose veins surgically by double ligature and avulsion. In order to speed ulcer healing, a ‘divine favor’ was invoked!

Late recurrent saphenofemoral junction reflux after ligation and stripping of the greater saphenous vein

Objective: This study was done to determine the long-term incidence of refluxing epifascial–to–deep vein reconnections in the area of the former saphenofemoral junction after ligation of the true junction, along with all proximal tributaries, and resection of the greater saphenous vein. Patients and Methods: A total of 125 limbs in 77 patients, representing 66% of 117 survivors among 602 patients who underwent operation between 1960 and 1967, were evaluated clinically and with duplex sonography for possible superficial–to–deep vein reconnections and clinical recurrence of thigh varicosities at a mean follow-up of 34 years. Results: Clinical examination suggested saphenofemoral recurrence in 59 limbs (47%). In 11 instances these were actually varices associated with isolated superficial system reflux or reflux originating from a distally located perforating vein. Color-coded duplex ultrasonography demonstrated saphenofemoral reflux in 75 limbs (60%), versus the 48 identified on clinical examination (P <.001), and documented that the junction ligation had not been performed incorrectly by absence of the terminal valve or any patent proximal saphenous remnant. The reflux originated at the site of the ligated saphenofemoral junction in 53 limbs (71%) and from a nearby circumjunctional deep vein in the other 22 (29%). Of the real junctional recurrences, 22 appeared as a tangled cluster, and 31 involved a single-lumen varix. Only 27 recurrences were sufficiently symptomatic to warrant consideration of additional treatment; 25 of these were clinically evident, single-lumen, true junctional recurrences. Conclusions: This 34-year clinical follow-up study shows a 60% incidence of junctional and circumjunctional reconnections after ligation of the true saphenofemoral junction and its related tributaries. Color-coded duplex sonography is a necessary concomitant to clinical examination, detecting more recurrences and defining the pathologic anatomy to direct clinically indicated additional treatments. (J Vasc Surg 2001;34:236-40.)