Tumor to Cerebellar Peduncle T2-Weighted Imaging Intensity Ratio Fails to Predict Pituitary Adenoma Consistency

Abstract

Object The consistency of pituitary macroadenomas affects the complexity of surgical resection. On T2-weighted (T2W) imaging, the intensity ratio of the tumor to the cerebellar peduncle (tumor to cerebellar peduncle T2-weighted imaging intensity [TCTI] ratio) correlates with meningioma consistency. We aimed to determine the correlation of this radiographic finding with pituitary macroadenoma consistency and to determine whether it can be used for preoperative planning.

Methods We performed a retrospective evaluation of 196 patients with macroadenomas who underwent endoscopic transsphenoidal resection from January 2012 to June 2017. Macroadenoma consistency was determined by one senior neurosurgeon at the time of surgery. Axial and coronal T2W magnetic resonance imaging images were evaluated retrospectively, and adenoma size, Knosp grade, suprasellar extension and TCTI were calculated.

Results The mean TCTI ratio was 1.70 (95% confidence interval [CI]: 1.65–1.75). Intraoperatively, 140 (71.4%) adenomas were classified as soft and 48 (24.5%) as fibrous. Gross total resection was achieved in 66.7% of fibrous adenomas and in 86.4% of soft adenomas (p = 0.007). The mean ratio was 1.68 (95% CI: 1.62–1.74) for soft tumors and 1.76 (95%CI: 1.67–1.84) for fibrous tumors. There was no difference in the mean TCTI ratio between groups. Lactotroph and somatotroph adenomas had a lower mean TCTI ratio compared with other functioning and nonfunctioning adenomas with a mean TCTI of 1.52 compared with 1.77.

Conclusions In this retrospective cohort study, we found that the TCTI ratio does not correlate with tumor consistency. We also noted that the TCTI ratio is increased in prolactin and growth hormone-secreting adenomas.

Keywords

macroadenoma - pituitary adenoma - transsphenoidal - consistency - T2-weighted imaging intensity

• References

• 1 Naganuma H, Satoh E, Nukui H. Technical considerations of transsphenoidal removal of fibrous pituitary adenomas and evaluation of collagen content and subtype in the adenomas. Neurol Med Chir (Tokyo) 2002; 42 (05) 202-212 , discussion 213
• 2 Couldwell WT. Transsphenoidal and transcranial surgery for pituitary adenomas. J Neurooncol 2004; 69 (1-3): 237-256
• 3 Taylor DG, Jane Jr JA, Oldfield EH. Resection of pituitary macroadenomas via the pseudocapsule along the posterior tumor margin: a cohort study and technical note. J Neurosurg 2018; 128 (02) 422-428
• 4 Snow RB, Lavyne MH, Lee BC, Morgello S, Patterson Jr RH. Craniotomy versus transsphenoidal excision of large pituitary tumors: the usefulness of magnetic resonance imaging in guiding the operative approach. Neurosurgery 1986; 19 (01) 59-64
• 5 Iuchi T, Saeki N, Tanaka M, Sunami K, Yamaura A. MRI prediction of fibrous pituitary adenomas. Acta Neurochir (Wien) 1998; 140 (08) 779-786
• 6 Yiping L, Ji X, Daoying G, Bo Y. Prediction of the consistency of pituitary adenoma: A comparative study on diffusion-weighted imaging and pathological results. J Neuroradiol 2016; 43 (03) 186-194
• 7 Snow RB, Johnson CE, Morgello S, Lavyne MH, Patterson Jr RH. Is magnetic resonance imaging useful in guiding the operative approach to large pituitary tumors?. Neurosurgery 1990; 26 (05) 801-803
• 8 Bahuleyan B, Raghuram L, Rajshekhar V, Chacko AG. To assess the ability of MRI to predict consistency of pituitary macroadenomas. Br J Neurosurg 2006; 20 (05) 324-326
• 9 Smith KA, Leever JD, Chamoun RB. Predicting consistency of meningioma by magnetic resonance imaging. J Neurol Surg B Skull Base 2015; 76 (03) 225-229
• 10 Smith KA, Leever JD, Hylton PD, Camarata PJ, Chamoun RB. Meningioma consistency prediction utilizing tumor to cerebellar peduncle intensity on T2-weighted magnetic resonance imaging sequences: TCTI ratio. J Neurosurg 2017; 126 (01) 242-248
• 11 Yao A, Pain M, Balchandani P, Shrivastava RK. Can MRI predict meningioma consistency? A correlation with tumor pathology and systematic review. Neurosurg Rev 2018; 41 (03) 745-753
• 12 Smith KA, Leever JD, Chamoun RB. Prediction of consistency of pituitary adenomas by magnetic resonance imaging. J Neurol Surg B Skull Base 2015; 76 (05) 340-343
• 13 Boxerman JL, Rogg JM, Donahue JE, Machan JT, Goldman MA, Doberstein CE. Preoperative MRI evaluation of pituitary macroadenoma: imaging features predictive of successful transsphenoidal surgery. AJR Am J Roentgenol 2010; 195 (03) 720-728
• 14 Chakrabortty S, Oi S, Yamaguchi M, Tamaki N, Matsumoto S. Growth hormone-producing pituitary adenomas: MR characteristics and pre- and postoperative evaluation. Neurol Med Chir (Tokyo) 1993; 33 (02) 81-85
• 15 Hagiwara A, Inoue Y, Wakasa K, Haba T, Tashiro T, Miyamoto T. Comparison of growth hormone-producing and non-growth hormone-producing pituitary adenomas: imaging characteristics and pathologic correlation. Radiology 2003; 228 (02) 533-538