Hirayama disease Imaging diagnosis: 1 case

On August 28, 2014, AJNR magazine published the following case report
.

The patient is a 20-year-old man with right upper extremity paresis and atrophy
of the muscles of his right hand.

Figure 1.
MRI T2 of the spinal cord in the straightened and lost position of the cervical spine shows hyperintensity of the C5-C6 segments of the spinal cord and local atrophy
of the spinal cord.

Figure 2.
MRI T2 of the spinal cord with cervical forward flexion shows ventral displacement of the spinal cord and the appearance
of an epidural "lesion" with ambiguous C3 to T3.

Figure 3.
MRI T2 of the spinal cord in posterior cervical suprae does not show signs of lesion shown in Figure 2, with corresponding epidural venous plexuses
.

Figure 4.
Horizontal STIR images can show localized spinal cord atrophy more clearly, especially on the right; Increased central spinal cord signaling, suggesting spinal
cord malacia.

Hirayama disease, also known as distal upper limb muscle atrophy or monolimb muscle atrophy in youth, is a self-limited cervical cord lesion caused by anterior flexion of the dural sac after the neck flexes and compresses the spinal cord, commonly seen in adolescents aged 15 to 25 years
.

Clinical manifestations: occult, chronically progressive muscle weakness and muscle wasting, mainly involving distal upper extremity muscle groups, whereas the brachioradial muscles are usually not affected
.

Key points of diagnosis: local cervical atrophy; abnormal curvature of the cervical spine; atrophy of the lower cervical medulla asymmetrically, with parenchymal changes; Adhesion after the posterior dural sac disappears; The posterior wall of the cervical dural sac is shifted anteriorly; thickening of the epidural tissue in the lower cervical medulla and posterior part of the upper thoracic cord; Increased flow in the epidural space suggests venous plexus dilatation
.

Differential diagnosis: syringomyelia, amyotrophic lateral sclerosis, myelopathy, spinal cord tumors
.

Treatment: Although the disease is self-limited, early diagnosis and early use of cervical harsir therapy are important
to prevent the progression of the disease.