December 27, 2018
A 59-year-old woman with a past medical history of autosomal dominant polycystic kidney disease and cerebral aneurysm, with concern for paraspinal neural tumor per chest CT; MRI was ordered for better evaluation.
Perineural cysts associated with autosomal dominant polycystic kidney disease (ADPKD)
- Background
- ADPKD is a hereditary, systemic condition that predominantly affects the kidneys with cystic replacement of the parenchyma and eventually renal failure. The liver, pancreas, spleen, and other organs may also be affected with cysts.
- Additional features include intracerebral aneurysms, cerebrospinal fluid leakage, arterial dissection of thoracic aorta and cervicocephalic vessels, and cardiac valve abnormalities. An association with perineural cysts has been reported as part of collagen-connective tissue disorder manifestations in ADPKD.
- Clinical Presentation
- Most are asymptomatic, but variable nerve root or spinal cord compression may be present. Low-back pain, radiculopathy (with or without paresis), and headache due to cerebrospinal fluid leakage may also occur.
- Key Diagnostic Features
- Most common localization is the cervical spine, followed by lumbosacral and thoracic spine. CT and MRI depict extradural, thin-walled, CSF density/T2 hyperintense, non enhancing, homogenous, noncalcified paraspinal cystic masses located at the neural foramina, with or without foraminal widening or bone remodeling.
- Differential Diagnosis
- Neural sheath tumors (schwannomas or neurofibromas): Can protrude through the neural foramen (dumbbell sign) which may be widened due to bone remodeling, they are usually solid and enhance to variable degrees
- Neurofibromatosis, Marfan and Lehman syndrome: may also be associated with paraspinal cysts
- Post-traumatic cysts: May be identical in appearance
- Clinical history is key to distinguish these entities.
- Treatment
- Mostly conservative (pain relief), but may require cyst aspiration or even microsurgical excision of the cyst with duraplasty or plication.
