The lateral accessory saphenous vein - a common cause of recurrent varicose veins.

BACKGROUND: Varicose veins commonly recur after surgery and present a large burden to the NHS. The aim of this study was to demonstrate that the lateral accessory saphenous vein is the commonest cause of groin recurrence of varicose veins and we discuss a possible anatomical reason for this. PATIENTS AND METHODS: The case notes of all patients presenting to two vascular surgeons with recurrent varicose veins over a 3-year period were studied. All limbs were assessed by duplex ultrasound scanning. These scans were reviewed to identify the site of recurrence. When recurrence occurred in the groin, the scans were further evaluated to identify the cause of groin recurrence. RESULTS: A total of 216 limbs in 186 patients were evaluated over a 36-month period. Of these, 141 (65%) demonstrated a recurrence in the groin: 56 (26%) recurrences were due to either incompetent thigh or calf perforators and there were 19 (9%) cases of saphenopopliteal or short saphenous vein incompetence. Out of 141 groin recurrences, 61 (43%) were due to a persistent lateral accessory saphenous vein. CONCLUSIONS: The lateral accessory saphenous vein is the commonest cause of recurrence in the groin of varicose veins. It should be looked for specifically during pre-operative assessment duplex scanning and at primary surgery. If identified at operation, we believe it should be either stripped or avulsed to reduce the risk of recurrence.

Primary branchial cleft carcinoma--a case report.

Primary branchial cleft carcinoma is a diagnostic challenge. The majority of cases have been shown, following the application of rigid criteria, to have developed from an occult metastasis elsewhere. We describe what we believe to be only the second reported case in a patient who fulfils all of the established criteria.

Compartment syndrome following prolonged pelvic surgery.

Compartment syndrome is a rare but serious complication of prolonged pelvic surgery. Prompted by two recent cases the authors studied the effect of limb angulation and elevation on Doppler ankle artery pressure and compartment pressure in ten normal subjects. Mean ankle pressure when supine was 130.5 (95 per cent confidence interval (c.i.) 124.5-136.5) mmHg and fell to 77.2 (95 per cent c.i. 64.6-89.8) mmHg in the Lloyd-Davies position with 10 degrees of head-down tilt. Reversing table tilt to bring the ankle elevation to 0 degrees in Lloyd-Davies supports restored mean ankle pressure to 114.3 (95 per cent c.i. 105.5-122.9) mmHg (P < 0.001). Placing the lower limb in calf supports was found to increase the mean intracompartmental pressure from 3.0 (95 per cent c.i. 1.2-4.8) mmHg to 11.6 (95 per cent c.i. 9.1-14.1) mmHg. Reversing table tilt significantly restores limb perfusion in patients undergoing prolonged pelvic surgery with the legs elevated and may protect against subsequent compartment syndrome.

Hemodynamic characteristics of failing infrainguinal in situ vein bypass.

The successful follow-up of distal arterial reconstructions for the identification of the failing bypass in the postoperative period hinges on a knowledge of the natural history of flow characteristics in these reconstructions. Over a 4-year period resting and hyperemic bypass flow, fistula flow, conduit diameter, and distal peak systolic velocity of 350 in situ bypasses were measured serially. B-mode ultrasound imaging of the entire bypass was performed to identify specific stenoses. Measurements were performed 5 to 9 days after operation, every 2 months for the first year, and every 6 months thereafter. Distal bypass flow less than 25 ml/min, a ratio of hyperemic/resting distal bypass flow less than 2.5, and vein size less than or equal to 3.0 mm inner diameter all correlated with bypass stenosis (greater than 50%) or occlusion (p less than 0.01). Contrary to previous studies, a distal peak systolic velocity of less than 45 cm/sec did not correlate with bypass stenosis or occlusion. A low distal peak systolic velocity did correlate with bypass stenosis or occlusion in bypasses larger than or equal to 3.5 mm inner diameter (p less than 0.03). However, no combination of these factors was able to accurately predict preocclusive stenosis or occlusion. Distal bypass flow was highest initially but reached a plateau 6 to 12 months after operation. Fistula flow, although very high initially, showed marked decrement with time.

Vein marking through ultrasound coupling gel.

It is now common practice to mark the course of the long saphenous vein by duplex scanning prior to in situ or reversed vein bypass grafting. This poses the problem of how best to mark its course durably in the presence of the ultrasound coupling gel on the skin. Blind to two observers, 11 commonly available marking pens were applied to the skin through ultrasound coupling gel, the gel was removed and the skin cleaned using a spirit-based antiseptic solution. The observers then rated the pens in order of performance. We recommend "Pilot Super Color Marker", "Artline 70" and "Edding 3020 Surgical Skin Marker" for preoperative vein mapping. These pens allow rapid marking of the saphenous or other veins through ultrasound coupling gel at the time of duplex scanning, and the marks persist after surgical preparation of the skin.

In situ bypass hemodynamics. The effect of residual A-V fistulae.

The effect of arteriovenous fistulae on in situ saphenous vein bypass hemodynamics and patency rates has been of great concern to some. It is our practice to ligate only those fistulae which conduct enough dye upon completion angiography to visualize the deep femoral venous system. We have prospectively studied 216 such bypasses using duplex ultrasound scanning to assess overall hemodynamic function over periods from 1 to 156 months postoperatively. Volumetric blood flow was measured in proximal and distal portions of the bypass choosing a region of uniform diameter with laminar flow. Mean fistula flow was derived by subtracting distal bypass flow from proximal bypass flow. Distal flow decreased significantly (p less than 0.01 paired t-test) from 68 +/- 4.6 ml/min (mean +/- SEM) at 2 months postoperatively to 51 +/- 4.8 ml/min at 12 months postoperatively. There was an overall decrease in fistula flow from 256 +/- 26.9 ml/min at 2 months to 86 +/- 22.6 ml/min at 12 months. In 14 of the 216 bypasses (6.5%), arteriovenous fistulae were ligated during the first postoperative year. This was necessitated by persistent increased fistula flow with or without edema and indication from PVR or segmental pressure of decreased resting flow or pressure. Following fistula ligation, fistula flow decreased and distal bypass flow improved. Within this select group of patients with reduced flow capacity, i.e., a proximal stenosis or small vein size, high fistula flow is poorly tolerated with a significant redistribution of flow resulting in reduced distal perfusion. However, for the majority of patients (95%), fistula flow does not deleteriously affect distal bypass flow.

Role of B-mode venous mapping in infrainguinal in situ vein-arterial bypasses.

Two hundred and eighty patients underwent B-mode mapping (B-map) of their saphenous vein over a period of 3 years (1984-1987) before lower limb revascularization. B-map deemed that 229 veins were suitable for bypass, 26 were questionable and 25 were unsuitable. A successful bypass was achieved in 97.8 per cent of the suitable group (all in situ), 85 per cent of the questionable group (in situ and composite vein), and 80 per cent of the unsuitable group (composite vein). At a minimum follow-up period of 1 year the overall patency rate was 95.0 per cent with a revision rate of 15.8 per cent. There was no correlation between revision rate and vein complexity or calf vein diameter. Calf vein diameter greater than 2.5 mm was correlated with a successful bypass (P less than 0.001). It is concluded that B-map is the investigation of choice for saphenous vein assessment before infrainguinal bypass surgery.

Flow/velocity characteristics of arterial bypass stenoses.

In the carotid system with relatively constant blood flow, peak systolic velocity within a stenosis (PSVST) can characterize the degree of hemodynamic stenosis. We have studied flow/velocity characteristics in an in vitro model of stenosis within conduits of varying diameters in an attempt to quantify the degree of stenosis from flow/velocity profiles in peripheral vein bypasses. A Harvard pulsatile flow pump (70 BPM) pumped human blood (HCT, 35-45%) through thin-walled polytetrafluoroethylene (3-6 mm in i.d.) into a variable peripheral resistance maintaining a constant mean blood pressure of 80 mm Hg over a flow range of 0-500 ml/min. A Diasonics DRF400 duplex scanner with a 10-MHz imager and 4.5-MHz Doppler probe was used to image and Doppler the conduits and measure flow through them. Validation of Doppler flow measurements (DF) was performed comparing them with flow measured (MF) by timed collection. PSVST within and pressure drop across a 50% stenosis was measured for each of the conduit's sizes over a range of 0-500 ml/min MF. The results show a good correlation between DF and MF (r = 0.99, P less than 0.001) for the whole range of internal diameters. In each 50% stenosed conduit, PSVST correlated well with MF (r = 0.95, P less than 0.001). Curves were constructed of MF vs PSVST for each 50% stenosed conduit. We conclude that measurement of volumetric flow, conduit diameter, and peak systolic velocity within a vein bypass can objectively predict bypass stenoses of 50% or greater.

Management of pediatric visceral arterial and aortic coarctation.

Two unusual pediatric vascular problems have been managed surgically. The first patient is a five-and-a half-year old girl who presented with renal artery stenosis and aneurysm and renovascular hypertension. This was treated by excision of the aneurysm and reimplantation of the right renal artery. The second patient is a two-year old girl with atresia of the abdominal aorta, superior mesenteric artery (SMA) and both renal arteries. She was treated by PTFE patch graft angioplasty of the aorta, SMA reimplantation and bilateral aorto-renal autogenous saphenous vein bypass.

Intra-operative and post-operative flow in the in-situ saphenous vein bypass.

We have attempted to further define the hemodynamic properties of the arterialized in-situ saphenous vein. The natural taper of the vein and the presence of arteriovenous fistulas are two unique factors associated with this conduit. Utilizing intra-operative electromagnetic flowmeter (EF) measurements and post-operative duplex ultrasound scanning (DUS), we have studied the natural history of these conduits from the time of their arterialization. The EF mean arterial blood flow in 71 in-situ bypasses was 100.8 cc/ml, range 25-200. No significant correlation was found between these measurements and angiographic runoff, vein diameter, pre- or post-operative Ankle/Brachial Index (ABI) and site of distal anastomosis. Three immediate failures requiring revisions were not predicted by EF flow measurements. Using the unique combination of Doppler ultrasound measurement and real time imaging, afforded by the DUS, fistula flow was determined. These studies showed that terminal bypass segment blood flow is not significantly affected by cutaneous fistula interruption. We found that duplex ultrasound scanning is a useful tool ideally suited to the study of the arterialized saphenous vein in-situ. One of its main advantages is the ability to accurately localize the site and hemodynamic significance of any arteriovenous fistulas.

Duplex scanning of the internal carotid artery: an assessment of cerebral blood flow.

Duplex ultrasound scanning (B-mode imaging and pulsed Doppler shift analysis) was used to measure internal carotid artery blood flow (ICBF) in 20 volunteers. The effect of changes in end tidal CO2 on cerebral blood flow was measured. When corrected to a PCO2, of 40 torr (5.32 kPa) internal carotid artery blood flow was 286 +/- 16 ml min-1 (mean +/- s.e.m.). Specific CO2 reactivity (the change in flow per torr change in CO2) was 8.16 +/- 0.69 ml min-1 torr-1 which was equivalent to 2.0 +/- 0.1 per cent of the flow at 40 torr per torr change in CO2 (percentage CO2 reactivity). The mean value and the CO2 reactivity compare favourably with previously reported measurements by other techniques. These data suggest that the non-invasive measurement of internal carotid artery blood flow by Doppler ultrasound scanning is an assessment of cerebral blood flow that can be used to study both normal and pathological changes within the cerebral circulation.

Evaluation of fiberoptic dermofluorometry as a means of clinically assessing tissue perfusion.

Fiberoptic dermofluorometry (FDF) transcutaneously measures fluorescence, following an intravenous injection of sodium fluorescein (NaFl), which is transmitted along a fiberoptic bundle to a photomultiplier tube and converted into dermofluorescence units (DFU). In five normal subjects studied, the plasma concentration of NaFl peaked at 5-15 minutes before decaying with first order kinetics and corresponding dermofluorescence (DF) rose to a peak between 10-20 minutes before decaying. Peak DF in the head and neck was significantly higher (P less than .001) compared to other skin sites which were similar. Application to patients (n = 16) undergoing successful lower limb revascularization showed a significant (P less than 0.01) improvement in perfusion at the foot level only. The reproducibility of FDF was poor when studied on the control limbs. We conclude that FDF does not, at present, constitute a valid measure of skin perfusion.

Extraperitoneal aortic bypass with exclusion of the intact infra-renal aortic aneurysm: the in-situ management of aortic aneurysms. A preliminary report.

Transabdominal aortic aneurysmorraphy with graft replacement is the generally accepted and most widely applied surgical approach in the treatment of infra-renal abdominal aortic aneurysm with a mortality rate of 2-5%. The alternative, retroperitoneal exposure of the aorta, although utilized for the first reported repair of an AAA by Dubost and championed by Rob, Stipa and Shaw, Helsby and Moosa and more recently by Williams et al., offers superior exposure and decreased post-operative morbidity. Despite these advantages, it is not commonly used by most vascular surgeons for the surgical management of aortic aneurysms. We have treated 35 patients using an extended retroperitoneal approach in which the aneurysm was treated by division of the infra-renal aorta, an end-to-end proximal anastomosis with an aortic bypass, and over-sewing of the aneurysm. In this group of patients, we found less post-operative physiological disturbances and a reduced requirement for blood transfusion. These data suggest that this method of retroperitoneal exclusion and bypass is generally applicable and is of particular value in the obese and/or the higher risk, medically disadvantaged patient.

Visceral aortic aneurysm in a 4 1/2-year-old child: an unusual complication of umbilical artery catheterization.

A 4 1/2-year-old girl had a 2.2 cm in diameter abdominal aortic pseudoaneurysm extending from above the celiac artery to 4 cm above the aortic bifurcation. This lesion developed after umbilical artery catheterization in the neonatal period, which also resulted in thrombosis of the right renal artery and renal atrophy. Patch graft angioplasty with polytetrafluoroethylene (Gore-Tex) was performed after excision of the aneurysm via a retroperitoneal approach.

Perioperative hypertension in patients undergoing carotid endarterectomy: shorter duration under regional block anesthesia.

Two alternative anesthetic techniques for use during carotid endarterectomy were studied in a series of 424 procedures. A total of 248 were performed in patients under general anesthesia and 176 patients received regional block anesthesia. Perioperative instability of blood pressure was noted in 108 patients. Hypertension was noted in 17.7% of those under general anesthesia vs 20.5% of those under regional block anesthesia. Intravenous vasodilator agents were used for 19.62 hr (+/- 4.33) in the general anesthesia group vs 1.4 hr (+/- 0.44) in the regional block anesthesia group (p less than .02). Perioperative hypertension correlated best with uncontrolled preoperative hypertension. Under regional block anesthesia the incidence of shunting was 4.5%. The 1 month operative mortality for the entire carotid series was 1.2% (5/424). There were three stroke-related deaths. In addition, two nonfatal major strokes and two minor strokes occurred in patients who received general anesthesia vs one nonfatal major stroke in a patient who received regional block anesthesia.

Initial experience comparing B-mode imaging and venography of the saphenous vein before in situ bypass.

Preoperative saphenous vein assessment was performed using both venography and B-mode scanning. Fifty patients underwent preoperative assessment, and the results were compared with the intraoperative findings. Both venography and B-mode imaging were equally accurate at determining the dominant saphenous system, but B-mode imaging missed five thigh double systems that were shown on venography. Neither venography nor B-mode imaging were good predictors of actual vein size at most sites in the leg, with the exception of B-mode assessment below the knee, where there was a positive correlation with intraoperative vein size (r = 0.80; p less than 0.01). In our study, B-mode scanning was consistently more reliable in determining vein presence and continuity than venography, which gave nine false-negative results. Finally, B-mode imaging allows the marking of a saphenous vein map on the patient's leg preoperatively as a guide to bypass surgery.

Transcutaneous flow measurements in in-situ bypasses: an assessment of duplex scanning.

Measurement of laminar flow using an ultrasound scanner was shown to have a high degree of correlation with quantified timed flows (r = 0.98, p less than or equal to .001). Sixty-one in-situ bypasses had flow assessed both proximally and distally. Mean fistula flow (proximal-distal flows) for time periods 1-8 weeks, 3 to 8, and 9+ months were 108, 85, and 16mls respectively. Distal bypass flow remained constant despite a significant decrease in fistula flow between the later time periods (p less than or equal to .001) (unpaired t-test). There was no evidence from the study that proximal flow through fistulas of varying resistances adversely affected the distal bypass flow.

The anatomy of the greater saphenous venous system.

To define surgical anatomy, a prospective study of the greater saphenous venous system in 385 instances in 331 patients was carried out with the use of prebypass phlebography (either pre- or intraoperative). The phlebographic interpretations were confirmed during the operative procedures and from the completion angiogram. These details were recorded and analyzed by a specific computer program. These data consisted of a number of superficial branches, perforators, the identification of valve leaflets, sinuses, and the size and position of the main venous trunk both in the thigh and in the calf. The study showed that a single trunk was present in the thigh in 65% of patients and in the calf in 45%. The remainder were variants of double systems. In two thirds of patients who had complete double systems, the larger system was used for in situ bypass but the rest required the use of parts of both systems. Phlebography was accurate in the depiction of the anatomic variations (93%), double systems, cross connections, and perforator branches (87%). However, the number of competent valves could not be accurately determined (accuracy, 68%). The diameter of the vein was frequently underestimated (in 80% by 1.1 +/- 0.4 mm) and hence could not be used as an index of vein adequacy. After phlebography, four patients had transient rises in serum creatinine levels and one had an iatrogenic thrombosis of a distal segment. This study suggests that the precise anatomy of the greater saphenous venous system should be determined preoperatively by phlebography since this information is valuable for proper surgical planning before vein is used as a graft or for in situ bypass in the lower extremity.