Huber T S, Back M R, Ballinger R J, Culp W C, Flynn T C, Kubilis P S, Seeger J M
Section of Vascular Surgery, University of Florida College of Medicine, Gainesville 32610-0286, USA.
J Vasc Surg. 1997 Sep;26(3):415-23; discussion 423-4. doi: 10.1016/s0741-5214(97)70034-x.
Magnetic resonance arteriography (MRA) of the lower extremities affords several possible advantages over conventional contrast arteriography (CA). We hypothesized that MRA of the infrageniculate vessels was sufficiently accurate to replace CA before revascularization procedures in patients with limb-threatening ischemia.
Fifty-three extremities in 49 patients were prospectively evaluated before attempted infrageniculate revascularization procedures with preoperative infrageniculate time-of-flight MRA (cost, $170/study) and standard contrast arteriography (cost, $1310/study) of the aortoiliac and runoff vessels. Independent operative plans were formulated based on the MRA and CA results before the revascularization procedure. Intraoperative, prebypass arteriograms (IOA; cost, $46/study) were obtained in all patients to confirm the adequacy of the distal runoff. The preoperative plans formulated by the results of MRA and CA were compared with the actual procedure performed based on the IOA. All arteriograms (CA, MRA, IOA) were reviewed after the operation by two independent reviewers, and the number of patent vessel segments and those with < 50% stenosis was determined.
Revascularization procedures were performed in 44 of 53 extremities (83%), and amputation was performed in nine extremities (17%) because of an absence of a suitable bypass target. The CA and MRA were equally effective in predicting the optimal operative plans as determined from IOA (CA, 42 of 53 [77%] vs MRA, 40 of 53 [75%]; p = 0.79). More patent vessel segments were seen on CA than MRA (reviewer A, 229 vs 174, kappa = 0.32; reviewer B, 321 vs 314, kappa = 0.46); however, a comparable number of segments were seen if the vessels of the foot were excluded. The accuracy (reviewer A, 78% vs 68%, p = 0.003; reviewer B, 75% vs 67%, p = 0.003) and sensitivity (reviewer A, 69% vs 51%, p = 0.001; reviewer B, 68% vs 46%, p = 0.0001) of CA relative to IOA were superior to those of MRA, although the specificity was comparable (reviewer A, 86% vs 90%, p = 0.31; reviewer B, 82% vs 87%, p = 0.52). The combination of MRA and IOA would have resulted in the optimal operative plan in 51 of the 53 cases (96%) and was comparable with CA and IOA (53 of 53; 100%; p = 0.50). Substitution of MRA and IOA for CA and IOA could potentially have saved an estimated $60,420.
The combination of MRA and IOA provides an accurate, cost-efficient strategy for visualization of the infrageniculate vessels before revascularization procedures.
与传统的血管造影术（CA）相比，下肢磁共振血管造影（MRA）具有若干潜在优势。我们推测，对于有肢体威胁性缺血的患者，在进行血运重建手术前，膝下血管的MRA准确性足以替代CA。
对49例患者的53条肢体在尝试进行膝下血运重建手术前进行前瞻性评估，术前行膝下时间飞跃法MRA（费用为每项研究170美元）以及主动脉髂动脉和流出道血管的标准血管造影术（费用为每项研究1310美元）。在血运重建手术前，根据MRA和CA的结果制定独立的手术方案。所有患者均在术中获取旁路前动脉造影（IOA；费用为每项研究46美元）以确认远端流出道的充分性。将根据MRA和CA结果制定的术前方案与基于IOA实际实施的手术进行比较。术后由两名独立的评估者对所有动脉造影（CA、MRA、IOA）进行评估，确定通畅血管段的数量以及狭窄程度小于50%的血管段数量。
53条肢体中的44条（83%）进行了血运重建手术，9条肢体（17%）因缺乏合适的旁路目标而进行了截肢。CA和MRA在预测根据IOA确定的最佳手术方案方面同样有效（CA，53条中的42条[77%]，MRA，53条中的40条[75%]；p = 0.79）。CA上显示的通畅血管段比MRA上多（评估者A，229条对174条，kappa = 0.32；评估者B，321条对314条，kappa = 0.46）；然而，如果排除足部血管，则观察到的血管段数量相当。相对于IOA，CA的准确性（评估者A，78%对68%，p = 0.003；评估者B，75%对67%，p = 0.003）和敏感性（评估者A，69%对51%，p = 0.001；评估者B，68%对46%，p = 0.0001）优于MRA，尽管特异性相当（评估者A，86%对90%，p = 0.31；评估者B，82%对87%，p = 0.52）。MRA和IOA相结合在53例中的51例（96%）中可得出最佳手术方案，与CA和IOA相当（53例中的53例；100%；p = 0.50）。用MRA和IOA替代CA和IOA可能节省约60420美元。
MRA和IOA相结合为血运重建手术前膝下血管的可视化提供了一种准确、经济高效的策略。
