Department of Neuroradiology, Hospital Dona Estefânia e São José, Centro Hospitalar Universitario de Lisboa Central, Lisbon, Portugal
- Publicação sob a forma de poster electrónico no 44th ESNR Annual Meeting, 29 setembro a 3 outubro de 2021, Geneva, Switzerland
- Neuroradiology 2021 Sep; 63(Suppl 1): 1-93. doi: 10.1007/s00234-021-02791-y
Introduction: Lesions affecting the conus medullaris can be divided according to their topographic location. They can be distinguished as arising extradurally, intradural-extramedullary or intramedullary. Intramedullary conus medullaris lesions include neoplasm, infection, inflammatory, congenital and vascular lesions. Conus medullaris tumours are responsible for 10% of all intramedullary spinal tumours. This region is mainly affected by tumours of glial cell type origin, with ependymoma being the most frequent one. However, other tumour types must be taken into consideration when evaluating this region. The most frequent complaint of patients with intramedullary conus tumour is lumbar back pain, which may be non-specific initially, with later progression to a defined bilateral leg pain, typically accompanied by bladder and bowel dysfunction. Motor impairment may only present at advanced stages, with the initial symptoms being treated conservatively. Hence, in most cases there is a delay of several months before a radiological diagnosis is established.
Method: We retrospectively collected cases of intramedullary spinal tumours in the conusmedullaris and provide a pictorial reviewdepicting the key clinical and imaging findings that can help narrow the differential diagnosis.
Result: In our series we describe five different cases of intramedullary spinal tumours involving the conus medullaris, including a renal cell carcinoma metastasis, a pilocytic astrocytoma, a high-grade glioma, an embryonal tumour of the CNS NOS and a primary CNS melanoma.
Conclusion: Imaging and particularly MRI is a cornerstone in the diagnosis of intramedullary tumours of the conus medullaris, evaluating its morphologic and signal characteristics, enhancement pattern and tumour extension. Since prompt treatment is essential for preventing progression of neurological deficits and allow symptomatic relief, the knowledge of the clinical background and the distinct imaging characteristics of the tumours that may affect this region can help narrow the differential diagnosis.
Keywords: Conus medullaris; Intramedullary tumour; MR imaging; Spinal tumours