Trancranial Doppler: value in clinical practice.

The value of TCD in clinical practice is well established since it can be used to measure cerebral vasomotor reactivity and to detect and grade vasospasm (VSP) following subarachnoid haemorrhage and cerebral blood perfusion consequences of extracranial ICA stenosis or occlusion. Intracranial steno-occlusive disease can be detected more reliably by transcranial color-coded imaging (TCCI) that provides a two-dimensional imaging of parenchymal and vascular anatomy of brain too. In patients with suspected brain TCD diagnostic criteria for brain death have a sensitivity of 91 to 100% and specificity of 97 to 100% and they are particularly useful when clinical and EEG evaluations are difficult. TCD is a sensitive technique for real time detection of microembolic signals (MES) from prosthetic cardiac valves, myocardial infarction site, atrial fibrillation, aortic arch atheroma and this suggests the use of TCD for monitoring response to antithrombotic therapy. There is also a high correlation between contrast-enhanced TCD and trans-esophageal echocardiography for detecting paradoxical embolism through right-to-left cardiac or pulmonary shunts. Microembolization detected by TCD monitoring may confirm features of unstable carotid artery plaques as imaged by Duplex scanning and there is an increasing evidence that asymptomatic MES from unstable carotid plaques are an independent factor for ischemic stroke. TCD can be used as a monitoring tool during cardiac surgery and cerebrovascular operations to determine critical hemodynamic changes in cerebral arteries and to identify high-intensity transients referred to air or particulate emboli. Several research studies of the past 10 years have shown that MES may be detected by TCD during all phases of CEA and CAS and that sustained microembolism after carotid flow restoration is an indication of impending postoperative or post-procedural occlusion. Our series showed a clear difference between the number of patients with MES and the incidence rate of MES in each patient submitted to CAS (100% of cases with 35-250 MES in each case) and to CEA (74% of cases with 2-30 MES in each case). We also observed a decrease in the incidence rate of microembolic events by TCD during CAS with or without brain protection devices , 18.% and 40%, respectively. There is a statistically significant difference between the neurological deficit related to embolism during CEA (1.8% of cases) and during CAS(9 %). Furthermore DWI has shown a higher prevalence of postoperative small areas of brain ischemia due to asymptomatic embolism occurring during CAS than after carotid surgery according with a higher incidence of patients suffering from neuropsychological impairment after CAS as compared with those submitted to CEA . The use of TCD can provide new insights into pathophysiology of cerebral steno-occlusive and functional diseases, it can helps in risk stratifications of patients with cardio-embolic sources and in the choice and monitoring of medical, surgical or endovascular treatment. TCD monitoring during carotid revascularization either surgical or endovascular can alert the operator to take appropriate measures to avoid brain ischemia and provides useful data for choice and control of the different brain protection devices.

Transcranial Doppler in 178 patients before, during, and after carotid endarterectomy.

From July 1991 to March 1995, 178 patients who underwent 198 carotid surgical repairs were investigated preoperatively, intraoperatively, and postoperatively by transcranial Doppler sonography (TCD). Preoperative TCD evaluation showed stenosis of the middle cerebral artery (MCA) in 4 patients (2.2%), siphon stenosis in 3 (1.6%), incomplete circle of Willis in 23 (12.9%), a decrease of mean blood flow velocity more than 70% of the basal value during digital common carotid compression in 31 (17.9%), and a critical reduction of vasomotor reactivity (no significant increase of mean blood flow velocity in the MCA during breath-holding test) in 34 (19.1%). Nine patients (5%) had surgery without preoperative angiography. In those patients the indication for surgery was based on color Doppler imaging and TCD investigations. Ninety surgical procedures were carried out under general anesthesia and 188 under locoregional anesthesia. In 37 surgeries (31.7%) a shunt was inserted. The use of a shunt was based on a decrease of mean blood flow velocity in the MCA below 50% of the basal value under general anesthesia or loss of consciousness combined with a decrease of mean blood flow velocity in the MCA higher than 70% of the basal value when locoregional anesthesia was employed. Intraoperative TCD monitoring showed a decrease of mean blood flow velocity in the MCA due to shunt malfunction in (8.3%) of 36 surgeries, turbulence of blood flow during declamping in 79 procedures (39.8%), and microembolic events in 10 patients (5%) that were related to one transient and one permanent neurological deficit. Another permanent deficit occurred in a patient without TCD signs. After surgery, TCD reliably detected an early asymptomatic occlusion of the carotid artery, hyperperfusion syndrome in 12 (6.0%), and an increase of vasomotor reactivity in 10 (29.4%) of 34 surgeries.

Rupture of Dacron aorto-femoral graft. Case report.

A 74-year-old patient was admitted to our department in a serious general condition due to massive bleeding. He had been treated 10 years previously in another hospital with an aorto-bifemoral bypass for obstructive disease using a knitted-Dacron graft. A large pulsating mass was present in the right iliac fossa as well as enormous pulsating enlargement of the scrotum. Echo color-Doppler investigation detected dilation up to 5 cm in diameter of the right branch of the graft and a large perigraft hematoma communicating with a similar mass in the scrotum. The patient was submitted to emergency surgery and a large rupture of the graft was found. The dilated segment was resected and replaced by a new 8 mm Dacron graft. Postoperative course was uneventful.

Carotid surgery without angiography is possible and safe.

BACKGROUND: To evaluate the possibility to perform carotid surgery without angiography. METHODS: From January 1994 to June 1998, 514 patients with carotid obstructive disease were operated upon, 225 of them (43.8%) without previous angiography; 55 out of 68 (80.8%) during the last six months. Eighty-one (36.0%) had lateralizing symptoms, 50 aspecific ones (22.2%) and 94 were asymptomatic (41.8%). All patients were investigated by color-coded duplex sonography (CDS) of the arteries at the neck and by transcranial Doppler (TCD) and computed tomography (CT). One hundred eighty-eight patients were operated upon under local anaesthesia and 37 under general anesthesia; 204 had a carotid endartereotomy (90.7%) with patch angioplasty in 154 (75.5%), and 21 required a bypass graft (9.3%). In 26 patients (11.5%) an indwelling shunt was needed. RESULTS: Findings at surgery were consistent with CDS for plaque composition, ulcerations and degree of stenosis. There were no early deaths. Neurologic or ocular deficits occurred in 2 cases (0.9%). No strokes were observed in follow-up from 6 to 34 months. CONCLUSIONS: Carotid endarterectomy can be done without angiography in selected cases provided CDS plus TCD are of high quality. Under such conditions it can be considered a safer way to deal with carotid obstructive disease.

Angiomegaly.

The authors report a clinical and ultrastructural study on a group of patients with angiomegaly, a vascular disorder characterized by elongated and distended blood vessels affecting the arterial (arteriomegaly) and/or venous system (venomegaly). The arterial group, drawn from a large arteriographic series, focuses on a comparison between atherosclerotic arteriopathy and arteriomegaly. The venous group, drawn from a large ultrasound series of vein disorders, is made up of patients with venomegaly. Venomegaly gives rise to few or no symptoms and it appears to be less frequent than arteriomegaly but as the latter proved to be associated in the majority of cases studied. Based on ultrastructural findings, the chief abnormality of angiomegaly seems to lie in a specific alteration of the elastic component of the vessel wall. We found slightly osmiophil amorphous elastic material neighbouring the basement membrane of the myocytes of the vessel walls. In the superficial parts of these myocytes occurred a great number of pinocytotic vesicles indicating for a rich creation of the new elastic material. Middle or highly osmiophil thick elastic fibers with irregular side protrusions were also found among myocytes remembering the moth-eaten picture. Results from a large ultrasonographic study on patients' relatives suggest an inheritability of this vascular disorder.

Prevention of deep venous thrombosis in vascular surgical procedures by LMW-heparin.

The risk of Deep Venous Thrombosis (DVT) in the immediate postoperative period varies from 0.8 to 96% of cases depending on major or minor operations and on age of patients. We have employed 8,000 I.U. AXa/daily of LMW-Heparin injected subcutaneously from one day preoperatively and prolonged for 8 days after surgical procedures in 40 patients operated upon by an aorto-femoral bypass in 25 cases, a femoro-popliteal below the knee in 8 and an extra-anatomical bypass in 7. The onset of DVP in the lower limbs was investigated by clinical examination, venous Doppler pressure evaluation, waveform analysis and echotomography and the 125I-Fibrinogen uptake test. There was no intraoperative increased bleeding and the preclotting of the prosthetic grafts was inaffected. A DVT was detected during the second postoperative day, by means of the 125I-Fibrinogen test in the calf of only one patient (1/40-2.5%), submitted to an aorto-bifemoral bypass, in whom the clinical pattern and ultrasound investigations were negative. The single daily subcutaneous administration has never caused side effects in the site of injection and it seems a real improvement in the heparin treatment. These results emphasize the advantage of the use of LMW-Heparins in patients submitted to arterial surgical reconstructions of the lower limbs for the prevention of the DVT.

Arterial repair of the lower limbs: prevention of prosthetic grafts occlusion by LMW-heparin.

The postoperative thrombosis of prosthetic grafts may be due to many factors: technical errors, poor run-off, prosthetic material, graft length, trauma by subcutaneous tunnellization or repeated microtrauma across the joint areas, evolution of atherosclerotic lesions, emorheological changes. In 50 patients submitted to surgical arterial repair of the lower limbs, we have employed 8,000 I.U. AXa/daily of LMW-Heparin, injected subcutaneously for 6 months after the operations to prevent immediate and late thrombosis. During the follow-up, one patient died, four stopped any treatment and in two the medication was changed. Hence our results are based on 43 cases: 10 patients operated upon by aorto-femoral bypass, 19 femoro-popliteal and 14 extra-anatomical procedures. During the follow-up all the patients were investigated by ultrasounds (pressure measurement, waveform analysis and duplex scanning echotomography); moreover 13/43 (30%) were studied by angioscintigraphy and 11/43 (25.5%) by a conventional or digital subtraction angiography. Thrombosis of the grafts at one year term occurred in none aorto-femoral, in one femoro-popliteal (5.2%) and in one extra-anatomical bypass (7.1%). This figure compares favourably with the results obtained in our experience in the patients treated by a variety of drugs. In such group the incidence of occlusion is 3.9% in aorto-femoral, 9.3% in femoro-popliteal and 11% in extra-anatomical grafts. Those results emphasize the possibility to improve the patency of the grafts in the arterial repair of the lower limbs by LMW-Heparin overall in femoro-popliteal and extra-anatomical areas.

Selection for surgery and long-term results in renovascular hypertension.

From 1960 to December 1977, 251 patients with renovascular hypertension (RVH) were observed; 219 were operated upon. Long-term results were assessed in 130 patients. Selection for surgery follows three steps: 1) screening of patients with renal artery disease, which is done by angiography; 2) diagnosis of RVH, which is reached mainly by differential renal function studies and renal vein renin measurements (ancillary methods are intravenous pyelography and sequential scintigraphy; the significance of renin measurements is discussed); and 3) prediction of the results of surgery and choice of technique. An original dynamic test of the authors is employed and reconstruction of the renal artery is the procedure of choice. This is done in the majority of cases by aortorenal bypass grafts using dacron prostheses. Techniques and complications are discussed and comparison with venous autograft is made. Hospital mortality was 3.2%. Overall long-term results were favorable in 78%. Long-term mortality was 6% and occurred mainly in patients who remained hypertensive. Results in atherosclerotic patients are compared with those obtained in fibrous stenoses. Results of renal artery reconstructions were far better than those of nephrectomies and lead us to restrict indications for such a procedure.

Xenon-133 muscular flow measurements in surgery for arterial disease of the lower limbs.

Muscular flow measurements were carried out in 34 patients with peripheral chronic arterial occlusive disease using the 133-xenon clearance method. The reactive hyperemia technique was preferred to the walking test. All the patients were investigated by angiography and 46 limbs were available for assessment. Control flow measurements were done after treatment in the following groups: arterial reconstruction in ten limbs of nine patients, unilateral lumbar sympathectomy in three and medical therapy in seven. Follow-up was from three to 12 months. The findings of flow measurements were of limited value in identifying the distribution of the arterial disease, but they provided a reliable means to predict the results of direct arterial repair in various procedures. They also proved to be a valuable method to assess the results of surgery. This does not seem to apply to lumbar sympathectomy or conservative treatment.

[Carotid-carotid bypass. Indications and results]. / Bypass carotido-carotideo. Indicazioni e risultati.

AIM: The aim of this study is to evaluate the indications for a carotid-carotid bypass and its therapeutic efficacy. METHODS: Between January 1995 and December 2001, 42 out of 782 patients with obstructive lesions of carotid vessels were submitted to carotid-carotid bypass. Preoperative investigations included Duplex scanning, transcranial Doppler and cerebral CT in all the patients, angiography in 24, spiral CT in 8, MR angiography in 6. Carotid bypass was planned pre-operatively in 13 cases due to internal carotid occlusion in 4, to pseudo-occlusion in 8 and to restenosis in 1. In the remaining 29, due to a too thin residual wall or to the lack of a good clivage plane, a carotid bypass was planned intraoperatively. A PTFE graft was employed in 30 cases while the autologous saphenous vein in 12. Four patients were lost in a 12-80-month follow-up. No intra or postoperative mortality was recorded. RESULTS: Three patients died during the follow-up. In 1 patient the death followed an ischemic stroke due to bypass occlusion. Four bypasses became occluded, in 3 cases without clinical signs. Eight patients suffered by transient superior laryngeal nerve iniury. CONCLUSIONS: Carotid bypass, as an alternative to CEA, provides good results in the treatment of the patients with carotid stenosis, pseudo-occlusion or segmental occlusion. In most of the cases the surgical technique is planned intraoperatively but in selected cases angiographic findings, spiral CT and color flow duplex can suggest in the preoperative phase that carotid bypass is the best choice.

[Elective and emergency surgical treatment of popliteal aneurysms. Indications and results]. / Trattamento chirurgico degli aneurismi poplitei in elezione e in urgenza. Indicazioni e risultati.

BACKGROUND: The aim of this paper is to evaluate the long term results related to surgical technique and to prosthetic material in planned and emergency conditions. METHODS: From January 1990 to December 1999, fourty-five patients with popliteal aneurysms were observed. Eighteen patients (40%) were asymptomatic; eleven (24.4%) suffered from claudicatio; six had an acute ischemia (13.3%) and four presented (8.9%) clinical signs of rest pain; in four cases (8.9%) symptoms were related to venous compression and to rupture in two (4.4%). Diagnosis was obtained by ultrasounds, angiography and CT-scan. All patients were operated on and in four cases (8.9%) the procedure involved both legs. The prosthetic material was reversed autologous saphenous vein (ASV) in 30 patients (61.2%), PTFE-EXS-TW in 16 (32.6%), homologous vein in one (2%), composite graft in one (2%), and a Dacron in the last one (2%). RESULTS: Six patients died for causes not related to the operation and eight bypasses (18.2%) became occluded. Amputation was needed in two patient, in relation to late bypass occlusion. In one cases an amputation was carried out for acute thrombosis of the contralateral aneurysm which was not treated for patients refusal. The long term patency rate was 81.8%. CONCLUSIONS: Popliteal aneurysms must be considered for reconstructive surgery, also when asymptomatic and with a diameter over 2 cm. The routinely use of the ASV improves the long-term patency rate. Best long term results are obtained in elective surgery.

[Ultrasonics diagnosis of venous thrombosis]. / Diagnosi con ultrasuoni delle trombosi venose.

Ultrasound phlebosonometry was employed in the examination of 54 subjects with phlebosonometric acute or recurrent in 20, chronic in 34 cases. The results of one or more phlebosonometric examinations were compared with the phlebograms. It was found that ultrasound investigation was reliable more for high (91%) than for low (65%) lesions and for acute (85%) as opposed to chronic (70%) thrombosis. The method is seen as of great importance in cases of phlebothrombosis, especially in acute femoroiliac forms. Even though it is a qualitative examination, and hence cannot take the place of angiography, it can nevertheless limit the use of the latter in cases where it could be dangerous.

Vascular injuries in supracondylar humeral fracture: an active approach to diagnosis and treatment.

AIM: The strategy with vascular complications of supracondylar humeral fractures (SHF) is under scrutiny since modern diagnostic techniques, particularly ultrasound investigations, provide earlier and more precise assessment and updated vascular surgical procedures, particularly microvascular ones, obtain excellent results. The purpose of this study was to look prospectively at what could be achieved by early systematic diagnostic investigations and, when appropriate, immediate arterial exploration and repair. METHODS: Sixty-three pediatric patients with SHF were admitted and treated in our Service between January 2007 and February 2014. Besides clinical examination, they were all investigated by color-coded Duplex scanning (CCDS) and ultrasound velocimetry (UV) of the hand. Eighteen patients were pulseless at first observation. Seven of them presented without signs of ischemia and regained their pulse post-reduction; only dislodgement and compression of the brachial artery (BA) was found in those children. In 11 patients, with pink hand in 7 and severe ischemia (white pulseless hand) in 4, lesions of the BA were detected. All were operated upon by various forms of arterial repair. CCDS and UV were used also intraoperatively and during follow-up (1 m-13 y). RESULTS: All patients had favorable early and long-term results: 8 came back to normal conditions, 2 had persistent paresthesia and weakness of the hand and 1 remained with partial disability of forearm and hand. All BA remained patent. CCDS correctly detected all the lesions preoperatively and showed the patency of the arteries after repair. CONCLUSION: Early assessment, use of ultrasound investigations and BA prompt repair seem to be the most logical and fruitful strategy at present time.