49 year old female with medullary thyroid cancer. Measure left parotid and left paratracheal lymph node. HEAD CT:Previously seen area of linear hypodensity involving the left parietal occipital region is again noted and unchanged compatible with known metastasis in this area seen on 12/10/07 that has been treated with radiosurgery. This residual hypodensity is most likely due to subsequent infarction. There is no definite enhancing mass lesion on this CT as was seen on the MRI. No new areas of vasogenic edema. The ventricles are normal and midline. The visualized calvarium and skull base are normal. There is mild opacification of the ethmoid air cells that is unchanged.No abnormal extra-axial fluid collections are identified. The ventricles are normal in volume and are midline.NECK CT:The previously described enhancing left parotid mass is again seen and appears slightly smaller in the same location where it was previously measured. The current measurements are 2.7 x 1.3 cm (image 43/1 on one). It is difficult to separate from the adjacent normal parotid gland. There are areas of circular hyperdense regions further superiorly that also appears slightly smaller. There is surrounding enhancing lymphadenopathy that is unchanged especially in the left parapharyngeal region. The fascial planes are within the left and a continue to be effaced with a mild amount of fat stranding in the subcutaneous tissues. Postsurgical changes of a radical left neck dissection are stable.High density within the left the region compatible with prior silicone injection, stable.The visualized lung apices are normal. There is an enlarged right paratracheal lymph node that is incompletely evaluated but appears slightly smaller in comparison to the prior examination measuring approximately 17x 8 mm (image 99/11). Please refer to the dedicated chest CT report performed at the same time. The visualized osseous structures are normal.
1. Stable region of encephalomalacia in the left parieto-occipital region most compatible with infarction post radiosurgery of a metastatic lesion in this area.2. Decreasing multi-loculated rim enhancing left parotid mass with stable surrounding lymphadenopathy.