What types of tumors, infections or other processes could cause a .7 x .8 cm enhancing lesion in the left lateral aspect of thecal sac at l4 level? i assume this is called intradural, extramedullary?

Neurofibromas : Most common tumors at this level are nerve sheath tumors called neurofibromas; others include meningioma s , vascular or blood vessel tumors, and other rarer tumors.

Need to see Mri : See a spine specialist that can correlate your symptoms with your radiology findings. The interpretation is based on whether the MRI was done with contrast, what your inflammatory markers show, and other components of your past medical history and physical exam.

It depends on Sympto: This might be some type of serious problem like a tumor. But it depends on the patient's symptoms. If the patient is symptomatic, he/she needs a complete medical evaluation to determine other sites of disease or tumor, as metastases from a known tumor can present like this. If the patient has spinal symptoms, then further evaluation is indicated . This may lead to a laminectomy to explore & biopsy.