History and Physical
A 13-year-old previously healthy male was playing basketball. After throwing the ball into the hoop, he presented with acute-onset paresthesias, followed minutes later by weakness of both upper limbs. Systems review was negative. He had no history of fever, trauma, drug ingestions, toxic exposures, or recent travel. Family history was significant only for a younger brother with autism; no relatives had a history of stroke, aneurysms, or brain tumors. He had no allergies to medications and his vaccinations were complete.
Physical examination showed weight 55 kg (50th percentile), height 160 cm (50th percentile), head circumference 55 cm (75th percentile), blood pressure 110/70, pulse 88 bpm, and temperature 37.8°C. On physical examination, he was alert without neck stiffness. Cardiorespiratory and abdominal examinations were normal. Neurological examination showed normal mental status for age, normal cranial nerves, and fundoscopy. Brachial diplegia was diagnosed based on hypoactive biceps and brachioradialis reflexes and absent pyramidal signs in the lower limbs. Sensory and autonomic functions remained normal. Due to suspicion of acute myelopathy, IV steroids were initiated, with no improvement after 30 days.
Diagnostic Workup
Initial head and cervical spine CT were normal. Cervical spine MRI showed mild cervical cord edema from C3 to C6. The following day, repeat MRI with contrast showed expansion of cord signal with restricted diffusion and patchy enhancement along the anterior horns from C2 to C7 ( Fig. 26.1 ). Brain and spine angiography were unrevealing.
Cord infarct. Spine MRI, (A) precontrast and (B) postcontrast sagittal T1, show hypointense central cord edema with patchy enhancement. (C) Sagittal and (D) axial T2 show corresponding hyperintensity with selective involvement of the central gray matter, particularly anterior horns. (E) Axial DWI demonstrates diffusion restriction. DWI , Diffusion-weighted imaging.
Lumbar puncture showed an opening pressure of 18 cm H 2 O. CSF protein was 0.34 g/L with negative cytology and cultures. EMG showed a motor neuronopathy from C2 to C6.
Clinical Differential Diagnosis
Common causes of pediatric myelopathy include inflammatory, infectious, compressive, and vascular.
Inflammatory/demyelinating disease is the most common cause of acute spinal cord syndrome in children. Most cases show multifocal involvement of the neuraxis, including brain, optic nerves, and/or spinal cord. Disease classification is based on phasicity and CSF serology. Treatment of chronic and/or relapsing disease includes various anti-inflammatory and immunosuppressive therapies.
Infections can present with nonspecific features including meningeal signs, motor asymmetry, and unclear sensory level. Clinical diagnosis of infectious myelitis requires pleocytosis (>10 cells/mm 3 ) or increased IgG in CSF. Alternatively, MRI showing cord edema and enhancement may be suggestive. To determine the likely pathogen, cultures and PCR can be helpful. It is important to consider the patient’s immune status, geographic location, and recent travel with exposures to endemic or tropical diseases. In children, cytomegalovirus (CMV), arboviruses (West Nile virus), and polio/non-polio enteroviruses can cause transverse myelitis, with fungi and mycobacteria less common.
Cord compression within the spinal canal can be seen secondary to large-volume hemorrhage, infection, and/or rapid tumor growth. This is the most emergent condition to rule out, as it requires rapid surgical decompression.
Vascular malformations, especially high-flow malformations such as arteriovenous malformation (AVM) or fistula, can present with acute or subacute progressive dysfunction.
Traumatic injury to the spinal cord can occur with subtle or no findings on initial imaging, yet progress to clinical deficits. This condition is termed spinal cord injury without radiographic abnormalities (SCIWORA) and is less common with the increased sensitivity of MRI, though delayed imaging may be required to identify subtle abnormalities.
Imaging Differential Diagnosis
Acute spinal cord infarction in children can be seen in the setting of recent trauma or infection. This commonly involves the vascular watershed zone in central gray matter, particularly the anterior horns, which are supplied by the unpaired anterior spinal artery. Associated findings can include vertebral body infarcts with marrow signal changes and disc herniation (fibrocartilaginous embolism) at the same level ( Fig. 26.2 ).
