[Usefulness of three-dimensional CT angiography (3D-CTA) with a single bolus injection of contrast material for the examination of intracranial and cervical arteries in cerebrovascular disease screening].

Three-dimensional CT angiography (3D-CTA) has been gaining wide acceptance as a clinically useful tool in the field of neurosurgery. The great diagnostic value of 3D-CTA for cerebral aneurysm or other cerebrovascular diseases has been well established. However, images of the intracranial and cervical arteries have not been obtained simultaneously because of the limitation of the scanning area and the need for contrast material. In order to use 3D-CTA to screen for cerebrovascular disease, we used a helical CT scan with an intravenous single bolus injection of contrast material to perform 3D-CTA of the intracranial and cervical arteries simultaneously. A spiral computed tomographic scan was performed with a Hispeed Advantage RP (General Electric). After injection of 150 ml of nonionized contrast material at a rate of 3 mm/sec in an antecubital vein, an axial computed tomographic scan (120 kV, 200 mA) of the cranial region was performed with a delay of 20-25 seconds after starting the injection. Section thickness was 1 mm with table increments of 1 mm per rotation. The scan volume included 20-30 mm above and below the sella turcica. An axial computed tomographic scan (120 kV, 190 mA) of the cervical region was performed with a delay of 30 seconds after completion of cranial CTA. Section thickness was 3 mm with table increments of 3 mm per rotation. Image reconstruction was carried out through surface rendering and maximum intensity projection processing. From November 1995 to August 1998, we used this technique to screen 218 consecutive outpatients for cerebrovascular disease. Unruptured cerebral aneurysms were found in 20 cases (9.2%). Atherosclerotic diseases of the cervical carotid artery were found in 58 cases (26.6%), as follows: carotid artery occlusion in 2 cases, carotid bifurcation stenosis in 22 cases, and intramural calcification of the internal carotid artery in 50 cases. Atherosclerotic diseases of the intracranial artery were found in 99 cases (45.4%), as follows: middle cerebral artery occlusion in 2 cases, middle cerebral artery stenosis in 21 cases, internal carotid artery stenosis in 2 cases, and calcification of the carotid siphon in 78 cases. Although our method has various technical problems that require further improvement, we conclude that it is a useful and noninvasive diagnostic modality for screening patients for cerebral aneurysms and other cerebrovascular diseases.

[A case of Terson's syndrome with an interesting MRI finding].

We report a case of a 62-year-old woman admitted to our hospital in a semicomatose state. CT scan and MRI on admission revealed a dense subarachnoid hemorrhage and intracerebral hematoma in the right frontal lobe. Digital subtraction angiography showed a saccular aneurysm located in the anterior communicating artery, so radical neck clipping of the aneurysm was performed via the right pterional approach. The operation was unevential. The patient complained of bilateral visual disturbance on the next day and FLAIR image of MRI demonstrated clearly crescent shaped and mobile high intense lesions corresponding to subhyaloid vitreous hemorrhage in both eye balls. The fundoscopic examination revealed an intravitreous hemorrhage which gradually disappeared over the next 12 days. Terson's syndrome after subarachnoid hemorrhage has been linked to an entity of poor prognosis, so it is beneficial that characteristic findings in FLAIR image of MRI can lead to correct diagnosis of Terson's syndrome earlier.

[Benefits of 0.5T MR diffusion-weighted images for super-acute-phase cerebral infarction].

Though diffusion-weighted images (DWI) have been increasingly used to detect super-acute-phase cerebral infarction in recent years, they have primarily been obtained through the use of high magnetic machines of more than 1.5T. In this study, we discussed the usefulness of DWI obtained using 0.5T MRI in comparison with CT, MRI (FLAIR and T2 weighted image) and SPECT (99mTc-HMPAO). DWI were able to detect ischemic lesions earlier than FLAIR or T2-weighted images. Scanning time was short at four seconds for eight slices, and the quality of image was sufficient for clinical usage. The most available b-value seems to be 800. There were less susceptibility artifacts in the 0.5T DWI than in the 1.5T DWI. From these data, we presume that it is possible to detect super-acute-phase cerebral ischemia on the 0.5T DWI, proving the clinical usefulness of DWI. Furthermore, DWI is considered useful in observing chronological changes in cerebral infarction, differentiation of abscess or brain tumor, diagnosis of moyamoya disease, degenerative disease and so on.

[Craniopharyngioma presenting a symptom of pituitary apoplexy and hyponatremia: a case report].

We report a case of a 70-year-old woman admitted to our hospital with sudden headache, drowsiness and hyponatremia. MRI on admission showed an intrasellar mass with suprasellar extension. Serum examination revealed decreased sodium and hypopituitarism, but they were normalized gradually by compensation using hydrocortisone, thyroid hormone and salt. Afterwards, masked diabetes insipidus appeared and required aqueous pitressin for the control of urine volume. A removal operation was performed uneventfully using the transsphenoidal approach and histological examination confirmed squamous-papillary type craniopharyngioma. Intratumoral hemorrhage of the craniopharyngioma is extremely rare. These cases tend to occur after over 15 years of maturation and the squamous-papillary type tend to bleed more than the adamantinomatous type. However, it is very difficult to make a differential diagnosis between craniopharyngioma with intratumoral hemorrhage and pituitary apoplexy, judging only by symptoms or interventional radiology. The definite mechanism of hyponatremia associated with a parasellar lesion is still obscure, but compression to the anterior hypothalamus or pituitary gland by an enlargement of the parasellar tumor is generally hypothesized.

[A case of symptomatic traumatic cerebral vasospasm associated with hyponatremia].

The pathogenesis and clinical course of traumatic cerebral vasospasm (TCV) are not yet fully understood. We report a case of delayed symptomatic TCV exaggerated by hyponatremia in spite of minor subarachnoid hemorrhage. A 77-year-old woman was admitted to our hospital with multiple injury caused by a traffic accident. Glasgow coma scale on admission was 8, and CT scan revealed right temporal lobe contusion, thin sub-arachnoid hemorrhage in the right sylvian cistern and right temporal bone fracture. The patient's consciousness level and CT findings improved gradually, but on the 11th day, she suddenly fell into a comatose state. No apparent change was observed on the CT scan, but her serum sodium level was markedly low (113 mEq/L). Under the suspicion of hyponatremia induced consciousness disturbance, sodium replacement therapy was commenced. She showed transient neurological recovery, but on day 13, worsening of left hemiparesis and a new low density area on CT were observed. Vasospasms of the right M2 proximal portion were confirmed by cerebral angiogram, so we performed intraarterial papaverine infusion leading to good extension of spastic vessels, but regrettably, there was no neurological recovery. In general, subarachnoid blood plays an important role in the delayed development of cerebral vasospasm, following not only aneurysmal rupture but also head injury. TCV tends to pass subclinically, but secondary water and electrolyte imbalance may unexpectedly cause TCV to manifest itself clinically. We can confirm that with this patient management of electrolyte balance following head injury was the most important strategy to avoid symptomatic TCV.

[Transverse myelitis in a patient with primary antiphospholipid syndrome--a case report].

A case of acute transverse myelitis following primary antiphospholipid syndrome was presented. The patient was 32-year-old Japanese female who was admitted to our hospital with paresthesia and weakness of the right upper extremity in September 1995. Neurological examinations revealed slight weakness and hypesthesia of the right arm and leg, impairment of vibration sense below the right knee, and hyperreflexia on the right side. There was no apparent history of systemic lupus erythematosus or multiple sclerosis. Laboratory investigations disclosed raised anticardiolipine antibody level of the IgG class. A magnetic resonance (MR) imaging of the cervical spine revealed changes in the spinal cord at C3-5. A gradual enlargement of the cord at C3-5 level was revealed on T1-weighted sagittal images; increased signal intensity at these same levels was visualized on T2-weighted images. Following administration of contrast material, an area of increased signal intensity was visualized within the cord extending from the C3/4 level to the C4/5 level in sagittal views and was located in the right lateral and posterior funiculus of the cord in axial views. After the admission, the patient's neurological symptoms worsened, and then we treated her by steroid pulse therapy. After that, the patient's symptoms gradually disappeared and the abnormal signal intensity of the spinal cord on an MR imaging disappeared. No evidence of recurrence was yielded by neurological examinations or neuroimaging studies. Antiphospholipid antibodies should be studied in all patients with transverse myelitis whether known to systemic lupus erythematosus, multiple sclerosis or not.

[Internal decompression with hippocampectomy for massive cerebral infarction].

Massive cerebral infarction due to the occlusion of a main cerebral artery is often unresponsive to medical treatment. Internal decompression with hippocampectomy was tried for two patients and satisfactory results were obtained without advancing cerebral edema. External decompression was also performed on 12 patients, but it was accompanied by intensified edema postoperatively. Satisfactory results were obtained in four cases, but three patients remained in vegetative states, and five patients died. The internal decompression with immediate hippocampectomy resolves compression to the brain stem without aggravating cerebral edema and may be more effective in preserving life than external decompression.