68M with headache • Xray of the Week
Figure 1. What is the important finding on these images.
Figure 2. CT of a planum sphenoidale meningioma.
A. Axial non contrast CT showing subtle density in midline frontal region (red arrows).
B. Coronal non contrast CT showing subtle density in midline frontal region (red arrows).
C. Axial CT with contrast showing enhancing midline mass (green arrow).
D. Coronal CT with contrast showing enhancing midline mass (green arrow).
Meningiomas are extra-cranial tumors which are attached to the dura in most cases (1, 4). Around 5-10% of meningiomas are suprasellar, which are subclassified as arising from the planum sphenoidale (PS), tuberculum sellae, diaphragma sellae, and anterior clinoid process (2). PS meningiomas can result in poor surgical outcomes due to its anatomic complexity (3). They can extend into nearby structures such as the sella turcica, posterior clinoid, and cavernous sinus (3).
MRI and CT are the gold standard when it comes to meningiomas. MRI specifically, since it has the ability to assess soft tissue characteristics including vascular supply and perfusion. CT is also useful since it can demonstrate any meningiomas effect on adjacent bone and in detecting psammoma calcifications (1). On non-contrast CT they appear isodense compared to adjacent brain tissue (Figure 1A, B). On contrast CT, the meningioma will enhance and may or may not appear homogenous (Figure 1C, D) depending on the presence of calcium, fat, and tumor necrosis (2). It is important to note that hyperostosis of adjacent bone suggests a benign meningioma that has infiltrated it on bone window. On MRI with contrast, meningiomas and their dural tail/attachment will enhance, which reflects dural infiltration and/or reactive vascularity. Calcifications may appear with low signal intensity or areas void of vascular flow (2). On T1w-MRI, meningiomas appear isointense or hypointense and signal variability on T2w imaging. The use of diffusion-weighted imaging has been shown to aid in predicting the histological grade of meningiomas (3).
Depending on the tumor size and involvement of adjacent structures, PS meningiomas may be removed using approaches such as endonasal transsphenoidal resection. Early decompression of the optic canal and orbiotomy are critical for total resection with excellent outcomes (5).
Ohba, S., Abe, M., Hasegawa, M., & Hirose, Y. (2016). Intraparenchymal Meningioma: Clinical, Radiologic, and Histologic Review. World neurosurgery, 92, 23–30. https://doi.org/10.1016/j.wneu.2016.04.098
Saloner, D., Uzelac, A., Hetts, S., Martin, A., & Dillon, W. (2010). Modern meningioma imaging techniques. Journal of neuro-oncology, 99(3), 333-340.
Ranabhat, K., Bishokarma, S., Agrawal, P., Shrestha, P., Ghimire, R. K., & Panth, R. (2019). Role of MR Morphology and Diffusion-Weighted Imaging in the Evaluation of Meningiomas: Radio-Pathologic Correlation. Journal of the Nepal Medical Association, 57(215).
Finn, J. E., & Mount, L. A. (1974). Meningiomas of the tuberculum sellae and planum sphenoidale: A review of 83 cases. Archives of Ophthalmology, 92(1), 23-27.
Mortazavi, M. M., da Silva, H. B., Ferreira Jr, M., Barber, J. K., Pridgeon, J. S., & Sekhar, L. N. (2016). Planum sphenoidale and tuberculum sellae meningiomas: operative nuances of a modern surgical technique with outcome and proposal of a new classification system. World neurosurgery, 86, 270-286.
Neal Joshi is a medical student and aspiring diagnostic radiologist at Rowan University School of Osteopathic Medicine in New Jersey. Prior to medical school, he did research with mouse models for Parkinson’s disease and L-DOPA induced dyskinesias. He also did an internship at Kessler Institute for Rehabilitation in a stroke lab analyzing MR images in ischemic stroke patients with hemispatial neglect. During his time at Rowan, he did research with animal models for traumatic brain injury with an emphasis on electrophysiology of neurons. He graduated from William Paterson University where he completed his studies in biology and biopsychology. Apart from medical school, Neal loves to read, skateboard, go on hikes, and spend time with his friends.
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Kevin M. Rice, MD is the president of Global Radiology CME
Dr. Rice is a radiologist with Renaissance Imaging Medical Associates and is currently the Vice Chief of Staff at Valley Presbyterian Hospital in Los Angeles, California. Dr. Rice has made several media appearances as part of his ongoing commitment to public education. Dr. Rice's passion for state of the art radiology and teaching includes acting as a guest lecturer at UCLA. In 2015, Dr. Rice and Natalie Rice founded Global Radiology CME to provide innovative radiology education at exciting international destinations, with the world's foremost authorities in their field. In 2016, Dr. Rice was nominated and became a semifinalist for a "Minnie" Award for the Most Effective Radiology Educator.
Follow Dr. Rice on Twitter @KevinRiceMD
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