Fabrizio Benedetti-Valentini

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 108 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. lntraoperative 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.

Imaging of carotid plaque angiogenesis.

Currently, characterization of the vulnerable plaque is a hot research topic as a more adequate strategy for preventing cerebrovascular events is being sought. Histological studies have recognized that plaque inflammation and the presence of adventitial vasa vasorum, intimal angiogenesis and plaque neovascularization are strong predictors of instability in atheromatous lesions of cerebrovascular and cardiovascular patients. The in vivo study of these features has been the focus of development of several new radiological imaging methods. Carotid ultrasound, with ultrasound contrast agents, is not only able to provide an enhanced assessment of the arterial lumen and plaque morphology with an improved resolution of the carotid intima-media thickness, but also to directly visualize adventitial vasa vasorum and plaque neovascularization. This technique and its future clinical implications are discussed in the present review.

Carcinoid syndrome in bronchial adenoma

Summary Two patients with bronchial adenomas and the carcinoid syndrome are reported. In addition, sixty-four similar cases were collected from the literature. Metastases in the liver or other organs are necessary to produce the carcinoid syndrome in the majority of the cases. However, in a few patients the primary tumor itself can lead to the onset of the typical symptoms. The measurement of the 5-HIAA level in the urine is now considered the most valuable method of diagnosis. Conversely, the serum serotonin level is not a precise index. The ideal management of a bronchial carcinoid is total excision even when metastases are present in the liver, since in some cases these can be removed. Furthermore, the patients can be treated more easily with drugs and they have a better prognosis.

Carotid body tumors: radioguided surgical approach

BackgroundCarotid body tumours (CBTs) are very rare lesions which should be treated as soon as possible even when benign since small tumour size permits easier removal and lower incidence of perioperative complications and recurrence. Malignant forms are rare and they can be identified by lymph node invasion and metastases in distant locations. The need of reliable and effective diagnostic modalities for both primary CBTs and its metastases or recurrence is evident.The present study reviews our experience and attempt to define the role of colour coded ultrasound (CCU) and Somatostatin receptor scintigraphy (SRS) with Indium-111-DTPA-pentetretide (Octreoscan®) using both planar and single photon emission tomography (SPECT) technique in the diagnosis and follow-up of these uncommon lesions within a multidisciplinary approach.MethodsFrom 1997 to 2008, 12 patients suffering from 16 CBTs (4 bilateral) were investigated by CCU and SRS-SPECT before and after surgery. All tumours were grouped according to Shamblins classification in order to assess the technical difficulties and morbidity of surgical resection on the ground of their size and relationship with the carotid arteries. Intraoperative radiocaptation by Octreoscan®) was also carried out in all cases to evaluate the radicality of surgery. All perioperative scans were evaluated by the same nuclear medicine physician.ResultsPreoperatively CCU showed CBTs (four were not palpable) with a sensitivity of 100%. Radioisotope imaging identified the CBTs as chemodectomas in 15 cases while no radioisotopic uptake was detected in 1 vagus nerve neurinoma. No evidence of metastasis or multicentricity were seen by total body radioisotopic scans. Combined data from CCU and SRS-SPECT allowed to determine tumour size in order to select 7 larger tumours which were submitted to selective preoperative embolization.Intraoperatively Octreoscan demonstrated microscopic tumour leftovers promptly removed in 1 case and an unresectable remnant at the base of the skull in another case.During follow-up CCI and radioisotope scans showed no recurrence in 14 cases and a slightly enlargement of the intracranial residual as detected during surgery in 1 patient.ConclusionCCU may allow an early and noninvasive detection of CBTs and hence safer operations. The combined use of CCU and SRS-SPECT provide useful data to identify those tumours and to evaluate their extent and carotid arteries infiltration. Radioisotope imaging is a sensitive modality to detect metastases and lymph node involvement that are markers of CBT malignancy. After surgery CCU and SRS-SPECT can be accurate modalities for surveillance for an early detection of CBTs recurrence.

Carotid body tumors: advantages of contrast ultrasound investigation.

Carotid body tumors are rare neoplasms that have to be considered in the evaluation of all lateral neck mass. Early surgical removal has been recommended to avoid possible cranial nerve injury, the most common perioperative complication. Computed tomography (CT) and magnetic resonance imaging (MRA) angiographies are the preferred pre‐operative diagnostic imaging investigations, as well as the 111 In‐pentetreotide scintigraphic scan, whereas the standard ultrasound investigations have poor sensitivity in characterizing of the blood flows of the parenchimal structure of the carotid body tumors. We describe a case of a patient with a carotid body tumor assessed with contrast ultrasonography that clearly improved the quality of the standard color Duplex. This technique may represent a non‐invasive method, easy to use and to repeat, and able to achieve high diagnostic accuracy.

Aorto-iliac/femoral reconstructions in patients with vasculogenic impotence.

One hundred and forty-eight patients out of 386 undergoing aorto-iliac or aortofemoral bypass had preoperative impotence, 37 of these were diabetics. In all of them Doppler studies revealed a penile/brachial pressure index less than 0.6 and an abnormal waveform analysis. Nocturnal penile tumescence was investigated in 44 cases and found to be abnormal. Angiography showed unilateral or bilateral obstructive lesions of the hypogastric arteries in 80%, in addition to aortic, common and external iliac and femoral lesions. One hundred and thirty patients (87.8%) had straight aorto-iliac/femoral bypass grafts inserted without a direct attempt to revascularise the hypogastric arteries but 24 had distal anastomoses to the bifurcation of the common iliac artery. In the remaining 18 patients the hypogastric artery was reconstructed on one side by an additional bypass or reimplantation on the graft. In 22 of 106 patients (20.7%) undergoing aortofemoral bypass, 18 of 24 (75%) with the distal anastomosis to the iliac bifurcation, and 14 of the 18 (77.7%) with revascularisation of the hypogastric arteries, erectile function was regained. A good result was obtained in only five of the diabetic patients (13.5%). Our experience suggests that: (1) impotence, as indicated by non-invasive investigations, was vasculogenic in origin since patients with the most effective revascularisation of the hypogastric arteries had the best results; (2) when it is feasible, revascularisation of the hypogastric arteries should be carried out more often, during the aorto-iliac or aortofemoral reconstructions, particularly in younger impotent patients; (3) aorto-iliac revascularisation restores potency in only a few diabetic patients.

Extra-anatomic graft infection in the aortofemoral area

Infection of extra-anatomic vascular prosthesis in the aortofemoral area is repor ted episodically in the literature so that its f requency is still uncertain, though in axillopopliteal grafts it was found to be 3.6%. 1 It is considered to be a benign disease with a good possibility of conservative t reatment or segmental resection. 2 In our experience over 15 years we had the impression that this was not always so, and that differences existed in incidence, severity, evolution, ways of t reatment and final outcome between cases operated upon for obstructive arterial disease and those treated by extra-anatomic bypass for the management of an infected aortic graft. Therefore we studied retrospectively a series of 213 consecutive patients in w h o m 225 grafts were implanted, analysing indications, t reatment and outcome.

Composite Grafts for Critical Ischaemia

A total of 236 femoropopliteal below the knee and 64 femorotibial bypasses were carried out for critical ischaemia of the lower limbs using various prosthetic materials. These were evaluated in order to assess the patency of composite grafts (29 cases) compared with autogenous saphenous veins (189) and polytetrafluoroethylene (PTFE) (82). The composite graft was made by anastomosing a segment of autogenous vein in the distal position and joining it by an end-to-end oblique anastomosis to a PTFE prosthesis in the proximal position. These grafts were employed when an adequate autogenous vein could not be used for the entire length of the bypass. The graft-graft anastomosis was never placed near the knee-joint and if the PTFE segment had to cross the knee, it was always of the externally supported type. There were no early occlusions in the composite grafts. A total of 257 grafts were available for assessment at a mean of 4 years (range 6 months to 15 years). The patency for autologous saphenous vein was: 81.2% (121/142 femoropopliteal and 13/23 femorotibial). The patency for PTFE was 67.1% (41/58 femoropopliteal and 4/9 femorotibial) and for composite grafts was 76% (10/11 femoropopliteal and 9/14 femorotibial). There was no significant difference in patency between the autologous saphenous vein and the composite grafts, both in the femoropopliteal and femorotibial positions. Both were significantly better than PTFE grafts. Composite grafts are the best alternative when an autologous saphenous vein is not available.

Buerger’s Disease of the Lower Extremities

Thromboangiitis obliterans or Buerger’s disease has its own particular pathological features. It is an inflammatory disease affecting both arteries and veins (angiitis), and it is an obstructive disease (obliterans) regularly complicated by thrombosis (thrombo). Small peripheral vessels are mainly, if not exclusively, involved both in the lower and the upper limbs; coronaries, cerebral and visceral vessels are only seldom involved.