An 82-year-old man presented with a 10-day history of progressive bilateral lower limb weakness and generalized numbness in his thorax and lower limbs. He reported a 3-week history of worsening gait ataxia, on a background history of 5 years of mild gait disturbance. On admission, the patient denied having problems with defecation, but had acute difficulty with micturition which resulted in catheter insertion. There was no history of spinal surgery, trauma, or spinal disorders. His medical history included ischemic heart disease, stroke, prostate cancer, and Paget's disease. Clinical examination was significant for a T4 sensory level, with reduced sensation to pin prick and light touch. Motor assessment revealed reduced power in bilateral lower limbs, with the following MRC grades: 1+/5 proximal and 3/5 distal. MRI was diagnostic for ISCH. T2-weighted images demonstrated ventral displacement of the thoracic spinal cord with moderate flattening, focal atrophy, and anterior herniation through the dura at T3-5 []. The CSF flow pattern dorsal to the cord at that level was preserved, but ventral to the cord, the CSF flow pattern was absent. Following a full discussion of the options with the patient, the decision was made for non-operative management. At 3 months after presentation, the patient remained neurologically stable.
A 66-year-old previously well man presented with an 18-year history of upper thoracic spine pain. The pain was initially intermittent and mild, but in the 14 months prior to presentation, it had gradually increased in severity and persistence. The pain radiated to the left side of the neck, and when severe, spread around both sides of the chest. The patient reported two episodes of left arm weakness lasting a few hours with spontaneous resolution, but denied paresthesia, sensory loss, or sphincter disturbance. There was no history of spinal surgery, trauma, or spinal disorders. Clinical examination demonstrated an upper thoracic spine gentle kyphosis. There were no abnormal findings on neurological motor, sensory, and reflex examination. A suboptimal quality MRI of the thoracic spine performed at a different institution was interpreted as an intradural mid-thoracic lesion, with a described intradural extramedullary mass indenting the dorsal aspect of the spinal cord. These findings were initially thought to be a dorsal arachnoid cyst. Repeat MRI at our institution demonstrated findings consistent with the characteristic features of ISCH. T2-weighted images showed anterior kinking and mild flattening of the spinal cord at T5, with widening of the subarachnoid space posterior to the cord and pulsation artifact within the CSF space []. The patient was treated with conservative management, with clinical and radiological surveillance. The patient remained neurologically stable at 4 months after presentation.