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UNLABELLED: We investigated the use of [18F]fluoro-2-deoxyglucose (FDG) PET scanning for assessment of skeletal muscle viability in patients with peripheral vascular disease and in patients following free-flap skeletal muscle transfer for closure of open wounds. METHODS: We obtained 32 FDG-PET scans from 30 patients, either at the time of admission for peripheral vascular disease (n = 16) or between 1 and 15 days after surgery for skeletal muscle transfer (n = 16). Ratios between injured and contralateral limb FDG tracer activity uptake were correlated with clinical outcome at 1 mo to 3 yr follow-up. RESULTS: Viable muscle uptake ratios ranged from 0.47 to 7.88 (mean: 2.26 +/- 1.81; n = 26), while nonviable muscle uptake ratios ranged from 0.12 to 0.46 (mean: 0.27 +/- 0.12; n = 6; p < 0.02). After skeletal muscle transfer, two patients with viable tissue, as documented by PET, required amputation due to osteomyelitis, and one patient with peripheral vascular disease who showed viable tissue by PET required amputation 3 mo after the PET scan because of recurrent ulcers. CONCLUSION: FDG-PET scanning can determine skeletal muscle viability in patients with peripheral vascular disease and in patients following free-flap transfer.

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Patients with cancer of the upper digestive tract may present with malnutrition, which may cause immunodepression and an increased rate of postoperative complications. In this study we describe the rationale and the feasibility of immediate postoperative enteral nutrition (NEPI) and evaluate its effectiveness for the nutritional support of patients undergoing surgery of the upper digestive tract. We studied 46 patients undergoing the following procedures: total gastrectomy (n = 22); oesophageal resection (n = 12); duodenocephalopancreasectomy (n = 12). NEPI was started on postoperative day 0 with a polymeric diet (calories: 53% as CHO, 22% as proteins, 25% as lipids) aiming at a calorie intake of 25 Kcal/Kg/day by postoperative day 4. It was possible to administer 24 Kcal/kg/day with the enteral diet from the 4th to the 10th postoperative day. Oral intake was resumed on average on postoperative day 13, and the mean hospital stay was 27 +/- 17 days. Tolerance of NEPI was good in most patients: only 5 patients (11%) interrupted the enteral nutrition. The mean postoperative weight loss was 3.7%. The rate of septic complications was 27%; mortality was nil. The surgical procedures caused a transient and reversible acute-phase decrease of nutritional and immunological parameters in the early postoperative period. However the NEPI preserved the nutritional status postoperatively as shown by the lack of significant changes in the nutritional indices at 10-14 days after surgery, as compared with baseline. In summary, we documented that NEPI can be started from postoperative day 0 with good intestinal tolerance, allowing adequate nutritional support, after extensive surgical procedures on the upper digestive tract.

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The feasibility of MR phase-sensitive imaging for the quantification of blood flow in the carotid arteries was studied in two normal volunteers and six patients with carotid artery and/or cerebrovascular disease. The technique consists of sensitizing the phase of the MR signal to blood flow velocity gated to different times in the cardiac cycle. Flow velocities and volumes were measured by using transverse planes in the common, internal, and external carotid arteries, and flow curves were generated. Measurements made by using flow phantoms correlated well with calculated results. The MR measurements yielded values between 250 and 580 ml/min for the total flow through each of the common carotid arteries in the two normal volunteers. Markedly reduced flow (about 50% below normal) was detected in a patient whose arteriogram showed severe occlusion of the internal carotid artery. In a second patient, who had a large frontal intracranial arteriovenous malformation noted by arteriography, the MR-quantified flow was abnormally high (about 1 liter/min). In the remaining four patients, the findings on phase-sensitive quantification were consistent with those expected from clinical and other laboratory studies (including arteriography and sonography). These preliminary findings suggest that MR phase mapping may be a feasible tool for the noninvasive quantification of carotid blood flow.

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Carcinoma of the base of the tongue is usually treated with radiation therapy. After a review of the literature, the findings are reported of 129 patients with squamous cell carcinoma of the base of the tongue treated in 1979-1983, with a minimum of a 3-year follow-up: 8 T1, 40 T2, 60 T3 and 21 T4 were found; only 48 cases were N0. Advanced stages (stage III and stage IV) were 83% of the total. External photon irradiation (Cobalt-60) was used in all cases; 33 patients underwent chemotherapy or surgery as additional treatment. The overall local control rate was 45.7%. Local control decreased as T stage advanced: T1 62.5%, T2 55%, T3 41.7% and T4 33.3%. The overall regional control rate for lymph nodes clinically palpable was 51.8%. The overall actuarial 5-year survival rate was 29.1%. The 5-year survival rate according to the N-staging varied from 37% for N0-stage to 17.4% for N3-stage. The majority of failures (92.8%) occurred within 2 years since the end of the therapy. Treatment complications, secondary carcinomas and causes of death are also discussed. Radiation therapy has proven to be effective for early-stage carcinoma of the base of the tongue; in more extensive lesions results are poor. Improved results could be obtained by optimal application of radiotherapeutic techniques. Knowledge of the various prognostic factors is essential to administer the therapeutic regimen for a given patient by the characteristics of his particular tumor.

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The trachea and main bronchi of a supine patient in a magnetic resonance (MR) scanner are not contained in a single standard coronal plane, but instead intersect this coronal plane at some angle, usually 20 degrees - 35 degrees. We have developed a new MR imaging protocol to determine the oblique imaging plane which best contains the trachea and main bronchi. The resulting oblique images simplify anatomical identification, and allow the user to select additional oblique planes which cut any desired portion of main bronchus in true cross section. Accurate lumen shapes and areas may then be extracted from these cross-sectional images. The method does not require the patient to be moved or rotated, and does not require hardware modification. We demonstrate the clinical application of the protocol with both a normal volunteer and a patient with an endobronchial tumor. The use of gradient echo pulse sequences together with this protocol to distinguish between vessels and bronchi is presented. We provide phantom verification to demonstrate the quantitative accuracy of the method to provide lumen areas.

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After a brief review of the literature, the results of the treatment by radiation therapy in 218 patients with tonsillar region carcinoma are reported. The patients were treated at the Turin University Radiotherapy Department (131 cases) and at the Radiotherapy Department of the Ospedale Maggiore, Novara (87 cases) from 1976 through 1984. The series included 29 T1, 88 T2, 64 T3 and 37 T4; 86 patients (40%) were N0. Only 49 patients were stages I and II (1/4 of the total). The local control (T) rate at the end of therapy was 63.5% for the overall series (139/218) ranging from 100% in T1, 72.6% T2, 54.6% T3 to 30% T4; the regional control (N) for patients with cervical lymphadenopathy was 66% (88/132). The overall 5-year survival was 38%; the 5-year disease-free survival was 35%. The 5-year survival according to T-stage was 52% for limited cases (T1-T2) in comparison to 22% for advanced ones (T3-T4). The 5-year survival for N0 stage was 55%; when neck nodes were present (N # 0) the survival was 29% after 5 years. Complications included 6 cases of trismus and 2 osteonecroses of the mandible. Second primary malignant diseases were seen in 17 cases (7.8%). The most common cause of death was failure in primary tumour control (80% of cases). In this series the results of radiotherapy of early stage tonsillar carcinomas are quite good; patients with large tumour masses fare less satisfactorily. Better results should be obtained in the future by identifying prognostic factors, monitoring potential causes of treatment failure and optimizing the radiotherapeutic treatment plan and technique.

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There are many methods available for the detection of thrombosis, none of which are noninvasive, rapid and accurate. Thrombospondin is a platelet protein that is present in the developing thrombus and may be an effective substance to use for imaging thrombosis. Vascular stenosis and thrombosis were produced in coronary, carotid and femoral arteries in eleven adult mongrel dogs. 131I labeled thrombospondin was administered to each animal to determine whether the radiotracer accumulated at the site of thrombus formation. The radioactivity per gram of vessels with thrombi was significantly different from the control vessels or whole blood (p = 0.0037 and p = 0.0015, respectively, paired t-test). This preliminary work suggests that iodinated thrombospondin accumulates at the site of thrombus formation. Labeled thrombospondin may be a rapid, safe and accurate method of detecting arterial thrombosis.

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A pulse sequence procedure for producing oblique magnetic resonance images is described. Using this procedure we present a new, accurate method to obtain true short-axis views and true long-axis views (both parallel and perpendicular to the septal plane) of the heart. The method is accurate regardless of the orientation of patient's heart. The method does not require the patient to be rotated, nor otherwise moved, and does not require any additional hardware. The method is experimentally verified with both human and phantom studies. The phantom study indicates accuracy of approximately 1 degree with a commercial scanner that reports angular measurements to a precision of 1 degree. Application of the short-axis views to measurement of left ventricular volume, and possible advantages of Gauss-Legendre integration for this measurement are discussed. Finally, multiphase oblique cardiac images are presented.

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The authors evaluate 117 patients affected by paranasal sinuses carcinoma treated by radiation therapy alone or by post-operative irradiation, from 1976 to 1984. Among these: 4 T1, 21 T2, 48 T3 and 44 T4; 66 cases were squamous cell carcinomas, 23 adenocarcinomas, 16 undifferentiated carcinomas and 12 adenoid cystic carcinomas. The overall 3 and 5 years actuarial survival rates were, respectively, 46% and 27%. The survival rates for stages T1 and T2 were 82 and 48% at 3 and 5 years; for stages T3 and T4 were 36% and 21%. According to the hystological type the survival rate varied from 50% for adenoid cystic carcinomas to 0% for undifferentiated carcinomas at 5 years. The survival rate for the group of patients treated with post-operative irradiation was 37% at 5 years, versus 10% for the group treated by radiotherapy alone. Complications have been minimal. Causes of failure are discussed. In conclusion, the authors consider a multicentric study as necessary to determine the efficacy of various schedules of treatment.

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Seven-pinhole tomographic and planar thallium-201 imaging was performed on 63 consecutive patients to assess the clinical value of these techniques. Significant coronary artery disease (stenosis greater than or equal to 70%) was present in 52 patients. Comparing the seven-pinhole results with those of the planar, the findings for sensitivity, specificity, and inter- and intraobserver agreement were, respectively, 94% against 75% (p less than 0.005), 91% against 91%, 86% against 79%, and 97% against 92%. In 25 patients in this group with a prior myocardial infarction, sensitivity was 100% for tomographic imaging and 92% for planar. In 27 patients without prior myocardial infarction, by contrast, sensitivity for tomographic imaging was 89% and for planar imaging 59% (p less than 0.01). Thus we conclude that both tomographic and planar imaging are highly sensitive for the detection of significant coronary artery disease, but tomographic imaging is significantly more sensitive in patients without prior myocardial infarction.

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