AJNR Blog » Parotid Neoplasms; Magnetic Resonance (MR) http://www.ajnrblog.org American Journal of Neuroradiology Thu, 02 Sep 2010 17:43:43 +0000 en hourly 1 Mass in septum pellucidum http://www.ajnrblog.org/2009/06/17/mass-in-septum-pallucidum/ http://www.ajnrblog.org/2009/06/17/mass-in-septum-pallucidum/#comments Wed, 17 Jun 2009 17:02:49 +0000 Impala http://www.ajnrblog.org/?p=1307
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Does anyone know what this mass could be? It was biopsied 2 years ago and pathology reported it as  “normal brain tissue”.

As you can see, the lesion is hyperintense on T2, hypointense on T1 and does not enhance.  No calcifications are present and no there is no restricted diffusion .

The patient is 25  year old and has loss of short term memory and seizures.

Any input into the nature of the mass is welcome.

]]> http://www.ajnrblog.org/2009/06/17/mass-in-septum-pallucidum/feed/ 0 Distinguishing of Pleomorphic Adenomas From Other Types of Parotid Tumors by Diffusion-Weighted MR Imaging http://www.ajnrblog.org/2009/02/03/distinguishing-of-pleomorphic-adenomas-from-other-types-of-parotid-tumors-by-diffusion-weighted-mr-imaging/ http://www.ajnrblog.org/2009/02/03/distinguishing-of-pleomorphic-adenomas-from-other-types-of-parotid-tumors-by-diffusion-weighted-mr-imaging/#comments Tue, 03 Feb 2009 18:17:41 +0000 hasanyerli http://www.ajnrblog.org/?p=335 Until now, many articles have been published to declare that apparent diffusion coeficient calculation (ADC) by diffusion-weighted imaging (DWI) is a helpful method for differantiating malignant from benign parotid gland tumors. Habermann et al. in 2005 described that diffusion-weighted echo-planar MRI seems to be a valuable tool for differentiating benign from malignant primary parotid gland tumors in fifty consecutive patients (1). We read with interest the recent article of the same group in the January 2009 issue of the AJNR (2). The authors reached one different conclusion in one hundred thirty-six patients with parotid tumors. They claimed that, DWI has the potential to differentiate only pleomorphic adenoma and myoepithelial adenomas from other parotid tumor types and state that “…in contrast to most other studies, an overlap regarding the ADC values from Warthin tumors and three different malignant subtypes of parotid gland lesions…” is present.

We would like to draw the authors’ attention to our report that is previously published in 2007 (3). We had already determined that DWI appears to be useful for distinguishing pleomorphic adenomas from other types of parotid gland tumors and calculating ADC values did not help to differentiate Warthin tumors from malignant parotid tumors. We are pleased that the good designed study with large patient population by Habermann and coworkers supports our results.

In our experience, morphologic criteria such as irreguler border, invasion of the mass and heterogeneous hypointense signals on T2-weighted images are still valuable in diagnosing malignant parotid tumors.

References

  1. Habermann CR, Gossrau P, Graessner J, et al. Diffusion-weighted echo-planar MRI: a valuable tool for differentiating primary parotid gland tumors? Rofo 2005;177:940-5.
  2. Habermann CR, Arndt C, Graessner J. Diffusion-Weighted Echo-Planar MR Imaging of Primary Parotid Gland Tumors: Is a Prediction of Different Histologic Subtypes Possible? AJNR Am J Neuroradiol published 8 January 2009, 10.3174/AJNR.A1412
  3. Yerli H, Agildere AM, Aydin E, et al. Value of apparent diffusion coefficient calculation in the differential diagnosis of parotid gland tumors. Acta Radiol 2007; 48: 980-7.
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