Smith Kyle A, Leever John D, Chamoun Roukoz B
Department of Neurosurgery, University of Kansas Medical Center, Kansas City, Kansas, United States.
Department of Radiology, University of Kansas Medical Center, Kansas City, Kansas, United States.
J Neurol Surg B Skull Base. 2015 Sep;76(5):340-3. doi: 10.1055/s-0035-1549005. Epub 2015 Apr 27.
Objective Pituitary adenomas are typically soft. The prevalence of fibrous adenomas is ∼ 5 to 13%. Firm tumors are difficult to remove by curettage or suction. Predicting fibrous adenomas by magnetic resonance (MR) imaging is typically difficult and unreliable. We propose a new prediction method based on MR T2-sequence intensity. Methods The MRIs of 36 consecutive patients with nonsecreting macroadenomas were evaluated preoperatively by a blinded radiologist. Using an MR T2-weighted sequence, regions of interest were sampled from the adenoma and cerebellar peduncle, and the ratio was calculated. Intraoperatively, tumors were graded prospectively for their consistency by the operating surgeon. Results There were 28 soft and 6 fibrous tumors. Unpaired t test for these ratios was found to be statistically significant (p < 0.0240; 95% confidence interval, -0.8229 to -0.06207). Mean values for soft tumors were found to be 1.918 (standard error of the mean [SEM] = 0.08212); firm tumors, 1.475 (SEM = 0.1179). Soft tumors were associated with ratios > 1.5 (sensitivity 100%; specificity 66.7%); firm tumors were associated with ratios < 1.8 (sensitivity 100%; specificity 42.9%). Conclusion Fibrous adenomas are typically diagnosed intraoperatively. However, their resection can be technically challenging. Using T2 intensity ratios on routine preoperative MRI allows identification of these challenging cases. The surgeon can then be better prepared for the surgical resection.
垂体腺瘤通常质地柔软。纤维腺瘤的患病率约为5%至13%。质地坚硬的肿瘤难以通过刮除术或抽吸术切除。通过磁共振（MR）成像预测纤维腺瘤通常困难且不可靠。我们提出一种基于MR T2序列强度的新预测方法。方法：由一位不知情的放射科医生对36例连续的非分泌性大腺瘤患者的术前MRI进行评估。使用MR T2加权序列，从腺瘤和小脑脚采集感兴趣区域，并计算比值。术中由手术医生对肿瘤的质地进行前瞻性分级。结果：有28例质地柔软的肿瘤和6例纤维瘤。发现这些比值的非配对t检验具有统计学意义（p < 0.0240；95%置信区间，-0.8229至-0.06207）。质地柔软肿瘤的平均值为1.918（平均标准误[SEM] = 0.08212）；质地坚硬肿瘤的平均值为1.475（SEM = 0.1179）。质地柔软的肿瘤与比值>1.5相关（敏感性100%；特异性66.7%）；质地坚硬的肿瘤与比值<1.8相关（敏感性100%；特异性42.9%）。结论：纤维腺瘤通常在术中诊断。然而，其切除在技术上可能具有挑战性。在术前常规MRI上使用T2强度比值可识别这些具有挑战性的病例。然后外科医生可以为手术切除做好更好的准备。
