Hiroshi Noguchi

Spinal cord herniation into associated pseudomeningocele after brachial plexus avulsion injury: case report.

OBJECTIVEPosttraumatic spinal cord herniation is a rare condition. We describe a case of spinal cord herniation into an associated pseudomeningocele after a brachial plexus avulsion injury. CLINICAL PRESENTATIONA 33-year-old man began to develop progressive Horners syndrome 14 years after a brachial plexus avulsion injury. At a clinical presentation 17 years after that injury, sensory disturbance and a unilateral pyramidal sign were also evident. In addition to myelography and computed tomographic myelography findings, coronal magnetic resonance imaging scans clearly demonstrated herniation of the spinal cord into a large pseudomeningocele inside the C7–T1 intervertebral foramen. Another pseudomeningocele inside the T1–T2 intervertebral foramen was also noted. INTERVENTIONThe patient underwent a C6–T2 laminectomy, during which the spinal cord was found to be herniated through a dural defect into a pseudomeningocele at the C8 root level, and a second dural defect was also shown, with an arachnoid outpouching that included an avulsed T1 root. The spinal cord herniation was reduced and the dural defects were repaired. After surgery, the patient showed no significant neurological changes, and his condition stabilized. CONCLUSIONBrachial plexus root avulsions may result in the formation of pseudomeningoceles and can lead to spinal cord herniation. Coronal magnetic resonance imaging is useful to demonstrate spinal cord herniation as well as pseudomeningoceles. Surgical treatment is recommended for such cases with progressive symptoms to prevent further deterioration.

Giant true posterior communicating artery aneurysm

The case of a giant posterior communicating artery (PCoA) aneurysm is reported in which the clinical presentation was Korsakoffs syndrome. Left carotid angiography revealed a partially thrombosed giant PCoA aneurysm. Three-dimensional computed tomography angiography showed the precise neck of aneurysm and surrounding structures from a multidirectional view. Hypoperfusion of the bilateral frontal, temporal, and medial inferior thalamus was seen on single-photon emission computed tomography. According to previous reports, giant true PCoA aneurysms are rare; in fact, there has been only one report of a giant true PCoA aneurysm. We discuss the radiological characteristics and the clinical presentation of giant true PCoA aneurysms.

Evaluating the effect of superficial temporal artery to middle cerebral artery bypass on pure motor function using motor activation single photon emission computed tomography.

OBJECTIVE We evaluated and analyzed the effect of superficial temporal artery to middle cerebral artery bypass for internal carotid artery occlusion on pure motor function using motor activation single photon emission computed tomography. METHODS Motor activation single photon emission computed tomographic (SPECT) images were obtained for nine patients who had undergone superficial temporal artery to middle cerebral artery anastomosis for symptomatic internal carotid artery occlusion. All motor activation SPECT images using the finger opposition task on the affected side were obtained before bypass surgery and at 1 week, 1 month, and 3 months after bypass surgery. The results of motor activation single photon emission computed tomography were expressed as negative or positive. RESULTS Before bypass surgery, the resting SPECT images revealed reduction of cerebral blood flow (CBF) on the affected side in all nine patients. The results of motor activation single photon emission computed tomography in three patients were positive. One week after bypass surgery, the results of the resting and motor activation CBF studies did not demonstrate any marked changes. One month after bypass surgery, the resting CBF increased in four patients. The results obtained for two of the patients revealed preoperative positive motor activation. The results of motor activation single photon emission computed tomography obtained for five patients were positive. Three months after bypass surgery, eight patients experienced improvement in the resting CBF, and the results of motor activation single photon emission computed tomography obtained for seven patients were positive. Among these, the results of preoperative motor activation single photon emission tomography obtained for four patients were negative. CONCLUSION Superficial temporal artery to middle cerebral artery bypass is useful not only for resting CBF but also for pure motor function based on motor activation SPECT images. From the preoperative motor activation study, it was concluded that patients with preoperative positive motor activation could attain the effect of bypass earlier than patients with preoperative negative motor activation.

De Novo Aneurysm Associated with Superficial Temporal Artery to Middle Cerebral Artery Bypass: Report of Two Cases and Review of Literature

BACKGROUND De novo aneurysm formation has been reported as a rare complication of superficial temporal artery (STA) to middle cerebral artery (MCA) bypass surgery. CASE DESCRIPTION The first patient with intracerebral hemorrhage had a ruptured de novo aneurysm arising from the recipient MCA at 6 years after undergoing STA-MCA bypass for hemispheric hemodynamic insufficiency. In the second case, an enlarging unruptured STA aneurysm was detected by follow-up magnetic resonance angiography at 8 years after the patient underwent STA-MCA bypass for moyamoya disease. Both patients were successfully treated by surgical clipping. CONCLUSIONS Persistent hemodynamic stress with hypertension in an artificial T-shaped vasculature and traumatic injury during surgical manipulation are the most important causes for de novo aneurysms after STA-MCA bypass. Follow-up magnetic resonance and computed tomography angiography examinations, along with appropriate blood pressure control, are recommended for patients who have undergone STA-MCA bypass surgery.

Ruptured True Anterior Choroidal Artery Aneurysm in Cisternal Segment

BACKGROUND Rupture of a true anterior choroidal artery (AChA) aneurysm in the cisternal segment is extremely rare, whereas cases of a distal AChA aneurysm associated with moyamoya disease are increasingly reported. CASE DESCRIPTION A 58-year-old woman presented with a severe headache and vomiting. Computed tomography demonstrated a subarachnoid hemorrhage without intraventricular or intracerebral hemorrhaging. Cerebral angiogram findings revealed a proximal AChA aneurysm mimicking an internal carotid artery aneurysm at the origin of the AChA. Intraoperative findings demonstrated a ruptured aneurysm located on a bend of the proximal AChA in the carotid cistern. Neck clipping of the aneurysm with preservation of the AChA led to a good outcome. CONCLUSIONS A rare case of ruptured true AChA aneurysm in the cisternal segment, unrelated to moyamoya disease, is presented as a cause of subarachnoid hemorrhage.

Two-stage operation for high cervical intramedullary ependymoma in young adult.

We describe a two-stage operation, rarely reported since being introduced in 1911, for treatment of an intramedullary ependymoma extending to the upper cervical cord in a young adult. This classic two-stage strategy combined with modern techniques remains a useful option for selected patients to safely remove intramedullary ependymomas.