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Purpose: To determine the frequency with which treatment plans based on findings at magnetic resonance angiography (MRA) match those based on findings at conventional x-ray arteriography (XRA) in the evaluation of symptomatic lower extremity ischemia., Patients and Methods: Two-dimensional time-of-flight (TOF) MRA was performed in 42 patients undergoing XRA for evaluation of symptomatic lower extremity ischemia. The blind interpretations and treatment plans based on MRA findings were compared with those based on XRA findings, with use of XRA as the standard of reference., Results: For identification of hemodynamically significant stenosis or occlusion, the sensitivity and specificity of MRA was 100% and 23% for iliac segments, 100% and 82% for common femoral segments, 89% and 67% for superficial femoral segments, 100% and 88% for popliteal segments, and 92% and 91% for tibioperoneal segments, respectively. The treatment plan based on MRA findings matched that based on XRA findings in 41% of patients., Conclusion: For evaluation of symptomatic lower extremity ischemia, two-dimensional TOF MRA cannot be considered a reliable substitute for XRA in patients who lack contraindications to XRA.

Purpose: To evaluate functional post-radiotherapy arterial change in a select patient population., Methods and Materials: Thirty-five seminoma patients were identified in the Radiation Oncology departmental records at Indiana University Medical Center. In this group the ipsilateral pelvis is treated with the contralateral pelvis available for evaluation as a matched control. Additionally, this group is generally young and unlikely to have pre-existing vascular disease, and shows excellent radiocurability with historically standard radiotherapy. Nineteen patients volunteered for a noninvasive vascular evaluation which included: Doppler ultrasound, segmental leg pressures, pulse volume recordings, and post-exercise testing. Average age at treatment was 36 (range 14-68) with an average follow-up of 8.8 years (range 1-20) with five patients now over 15 years post-treatment. The majority of the patients received 2500-2600 cGy., Results: Three of 19 patients had abnormal vascular evaluations. Of these, two had bilateral abnormalities not felt to be solely associated with irradiation. The remaining patient showed both resting and post-exercise ipsilateral vascular abnormalities. Irradiation was the only identifiable etiologic agent for this patient's vascular abnormality., Conclusion: Subclinical vascular change attributable to low dose radiotherapy was identified in one of 19 patients (5%). Considering the radiocurability of seminoma patients this incidence is acceptable. In light of this slight, yet documented, arterial abnormality occurring with low dose radiotherapy, we recommend additional study of high dose radiotherapy patients to determine the incidence and morbidity of radiation-induced arteriopathy in this group.

This study prospectively compared the following tests for their accuracy in amputation level selection: transcutaneous oxygen, transcutaneous carbon dioxide, transcutaneous oxygen-to-transcutaneous carbon dioxide, foot-to-chest transcutaneous oxygen, intradermal xenon-133, ankle-brachial index, and absolute popliteal artery Doppler systolic pressure. All metabolic parameters had a high degree of statistical accuracy in predicting amputation healing whereas none of the other tests had statistical reliability. Amputation site healing was not affected by the presence of diabetes mellitus nor were the test results for any of the metabolic parameters.

Transcutaneous oxygen and carbon dioxide pressure (PO2 and PCO2) foot monitoring was compared with ankle Doppler-derived systolic pressure regarding their respective abilities to discriminate the severity of limb ischemia before vascular reconstruction and to predict surgical outcome early in the postoperative period. Transcutaneous PO2 (tcPCO2), foot-chest tcPO2 index, transcutaneous PCO2 (tcPCO2), foot tcPO2/tcPCO2 index (tcPO2/tcPCO2), ankle Doppler systolic pressure (AP), and ankle-brachial pressure index (ABI) were determined in 89 revascularized limbs. The measurement of tcPO2 and foot-chest tcPO2 was found to be more sensitive to degrees of severity of limb ischemia and more closely associated with the outcome of revascularization than AP and ABI. TcPCO2 and tcPO2/tcPCO2 were not useful in assessment of the vascular patient undergoing reconstructive surgery. Before operation, tcPO2 less than or equal to 22 torr and foot-chest tcPO2 less than or equal to 0.46 indicate severe limb ischemia requiring urgent revascularization. After operation, tcPO2 less than or equal to 22 torr and foot-chest tcPO2 index less than or equal to 0.53 indicate that revascularization is likely to fail. We conclude that tcPO2 monitoring, as a metabolic test of actual tissue perfusion, is a more reliable indicator of preoperative limb ischemia and postoperative outcome of revascularization than hemodynamic, Doppler-derived pressure tests.