Maroldi R, Farina D, Battaglia G, Maculotti P, Chiesa A
Cattedra di Radiologia, Università di Brescia.
Radiol Med. 1996 Mar;91(3):211-8.
This study was aimed at comparing CT and MRI in the preoperative staging of sinonasal malignancies and at developing the most cost-effective diagnostic strategy to determinate resectability and choice of surgery and to assess surgical demolition extent. Forty-nine patients with sinonasal tumors were examined during a 10 years' period, with CT (20 patients), MRI (13 patients) and combined CT and MRI (16 patients); 42/49 patients underwent surgical resection (16 patients with craniofacial resection and 6 with orbital exenteration). Cost-effectiveness of the two techniques was assessed comparing five protocols using CT and MRI either alone or combined. In 40/98 orbits the tumor was in contact with a bone wall. MRI was more accurate than CT in assessing orbital invasion (100% sensitivity, 94% specificity, 86% positive predictive value and 100% negative predictive value, vs. 50%, 93%, 75% and 82%, respectively, for CT). MRI showed the tumor in contact with the skull base in 24/49 patients and CT in 23/49 patients, with no statistically significant difference between the two techniques. Dural infiltration, however, was better demonstrated with MRI in 3 patients with minimal bone erosion of the nasal vault. In 5 patients CT and MRI showed pterygopalatine fossa invasion (4 true positives and 1 false positive for both techniques). Since the final decision about orbital exenteration needs accurate surgical mapping, CT appears to yield all the pieces of information necessary for surgical planning. The most cost-effective protocol seems to be a CT examination for all patients. MRI is needed only for better prognostic assessment in the patients with minimal bone erosion of the floor of anterior cranial fossa. In fact, dural invasion, which is a markedly negative factor for survival, may be missed by CT.
本研究旨在比较CT和MRI在鼻窦恶性肿瘤术前分期中的应用，并制定最具成本效益的诊断策略，以确定可切除性、手术方式的选择以及评估手术切除范围。在10年期间，对49例鼻窦肿瘤患者进行了检查，其中20例患者接受了CT检查，13例患者接受了MRI检查，16例患者接受了CT和MRI联合检查；42/49例患者接受了手术切除（16例患者行颅面联合切除术，6例患者行眶内容物剜除术）。通过比较单独使用CT和MRI或两者联合使用的五种方案，评估了这两种技术的成本效益。在98个眼眶中，40个眼眶的肿瘤与骨壁接触。在评估眼眶侵犯方面，MRI比CT更准确（敏感性100%，特异性94%，阳性预测值86%，阴性预测值100%，而CT分别为50%、93%、75%和82%）。MRI显示49例患者中有24例肿瘤与颅底接触，CT显示49例患者中有23例，两种技术之间无统计学显著差异。然而，在3例鼻腔顶部骨侵蚀轻微的患者中，MRI对硬脑膜浸润的显示更好。在5例患者中，CT和MRI均显示翼腭窝侵犯（两种技术均有4例假阳性和1例假阴性）。由于关于眶内容物剜除术的最终决定需要精确的手术定位，CT似乎能提供手术规划所需的所有信息。最具成本效益的方案似乎是对所有患者进行CT检查。仅在前颅窝底骨侵蚀轻微的患者中，为了更好地进行预后评估才需要MRI。事实上，硬脑膜侵犯是一个明显的生存负面因素，CT可能会漏诊。
