July 2014

Introduction

Diffusion Imaging to Characterize Tumor Cellularity

Asim Choudhri

Asim Choudhri

Diffusion-weighted imaging rose to prominence due to its ability to rapidly detect early signs of cellular metabolic shutdown (cytotoxic edema), and it quickly became the gold standard for the detection of acute cerebral infarction. While DWI is typically evaluated in a qualitative manner, quantified calibrated information can be obtained in the form of apparent diffusion coefficient maps. … more »

Head & Neck

Apparent Diffusion Coefficient Mapping of Salivary Gland Tumors: Prediction of the Benignancy and Malignancy

Sato Eida

Sato Eida

Preoperative prediction of tumor malignancy is clinically very important, because this information strongly influences the surgical plan. Diffusion-weighted imaging is very sensitive to biophysical abnormalities associated with pathologic changes; in this regard, apparent diffusion coefficient measurement has been used to diagnose benign and malignant salivary gland tumors. However, salivary gland tumors are composed of distinctive tissues, … more »

Head & Neck

Diffusion-Weighted MRI: Distinction of Skull Base Chordoma from Chondrosarcoma

Kristen W. Yeom

Kristen W. Yeom

A few years ago we encountered a series of very rare and aggressive chordomas of the skull base and sacrum in four young children, referred to as poorly differentiated chordomas. While it is commonly known that chordomas are T2-bright, these were very dark. So dark, in fact, that we had initially considered them embryonal … more »

Brain

Primary Cerebral Lymphoma and Glioblastoma Multiforme: Differences in Diffusion Characteristics Evaluated with Diffusion Tensor Imaging

Cheng Hong Toh

Cheng Hong Toh

One of the earliest and most commonly studied applications of diffusion tensor imaging to brain tumor imaging has been the attempt to use apparent diffusion coefficient and fractional anisotropy (FA) measurements to estimate glioma grade. But results have been mixed, and it is difficult to draw any firm conclusions. In contrast, ADC has consistently … more »

Brain

Distinguishing between Germinomas and Pineal Cell Tumors on MR Imaging

Netsiri Dumrongpisutikul

Netsiri Dumrongpisutikul

Pineal region tumors constitute 1% of all intracranial tumors.1 Among the various histologic types of pineal tumors, the germ cell tumors are more frequent than the pineal cell origin tumors.2 Our research aimed to differentiate between germinomas and pineal cell tumors based on ADC values and MR imaging characteristics. The previous literature suggests that the … more »