MRI of intraspinal nerve sheath tumours presenting with sciatica

Area of Science:

• Neurology
• Radiology
• Oncology

Background:

• Sciatica is a common symptom with various causes.
• Intraspinal nerve sheath tumors (NST) are a less common but significant cause of sciatica.
• Accurate diagnosis of NST is crucial for effective treatment.

Purpose of the Study:

• To review the magnetic resonance imaging (MRI) characteristics of intraspinal nerve sheath tumors (NST) presenting with sciatica.
• To evaluate the utility of MRI in differentiating NST from other spinal pathologies.
• To identify specific MRI features that may help distinguish between different types of NST.

Main Methods:

• Retrospective review of MRI characteristics of 14 intraspinal nerve sheath tumors (NST).
• Analysis of T1-weighted (T1W) and T2-weighted (T2W) images.
• Evaluation of contrast enhancement patterns following Gadolinium-Diethylenetriamine penta acetic acid (DTPA) injection.

Main Results:

• NST were typically iso- or hypointense on T1W images and hyperintense on T2W images.
• All tumors were detectable on unenhanced T1W images.
• Intense enhancement was observed after Gadolinium-DTPA injection, aiding differentiation from disc fragments.
• Homogeneous enhancement was common, except in recurrent tumors.
• Rim enhancement was more frequent in schwannomas than neurofibromas, though unenhanced images could not distinguish between these two types.
• Poor correlation between lesion site and clinical findings was noted.

Conclusions:

• MRI is effective in detecting intraspinal nerve sheath tumors (NST) presenting with sciatica.
• Gadolinium-enhanced MRI aids in differentiating NST from sequestrated disc fragments.
• Specific enhancement patterns may help differentiate schwannomas from neurofibromas.
• MRI evaluation for sciatica should include the lower thoracic region, particularly when lumbar disc herniation is absent.