Spread of blood in cerebrospinal fluid following craniotomy simulates spinal metastases.

Postoperative myelography with water-soluble contrast media was performed in 36 children with a diagnosis of posterior cranial fossa tumour. The myelograms were normal in 15. In 5 an intramedullary tumour was present and 3 of these had in addition subarachnoid changes as evidence of tumour spread. The remaining 16 patient had subarachnoid changes of a different character, mainly located in the posterior thoracic region and similar to those seen after subarachnoid haemorrhage. It is suggested that they represent adhesions caused by blood from the operation. The blood is assumed to be distributed by the large cerebrospinal fluid pulsations to the cervical and thoracic regions. It is important to recognise and differentiate subarachnoid changes due to tumour and to postoperative adhesions to avoid unnecessary radiotherapy to the spinal cord.

Volumes of chronic traumatic frontal brain lesions measured by MR imaging and CBF tomography.

The volumes (ml) of chronic traumatic frontal brain lesions were compared measured "morphologically" with MR imaging (T1 and T2 weighted images) and "functionally" with a tomographic rCBF technique (SPECT with 133Xe i.v.). The T1 volumes varied between 11 and 220 ml. The correlation between T1 and T2 volumes was 0.95, the T2 volumes being 33% larger than T1 volumes (p less than 0.001). The functional SPECT volumes were considerably larger (range 16-324 ml) than the MR volumes. The mean volume difference was 81% between T1 and SPECT images (p less than 0.001), and 35% between T2 and SPECT images (p less than 0.001). Correlations between the MR and SPECT volumes were also higher for T2 than T1 volumes. The volume difference is most likely explained by a functional decrease in regions around the lesion in which no morphologic change visible on MR images had taken place. MR and SPECT volume measurements were positively related to persistent lack of energy and personality changes, but only moderately related to duration of impaired consciousness and neuropsychologic outcome.

Reversible changes on computed tomography scans of the brain during induction therapy for acute lymphoblastic leukemia in children.

Children with acute lymphoblastic leukemia (ALL) have been shown to develop changes on computed tomography (CT) scans of the brain. These changes are seen both during and after therapy. Some of the results have been contradictory. Nine children with ALL were examined by CT of the brain during induction therapy. All children showed normal CT scans on the day of diagnosis. One month later all had dilatation of the ventricles and widened sulci. During the next 9 months the CT scans gradually were normalized. We conclude that such changes in CT scans of the brain are transitory and are caused by the high dose of prednisolone administered during induction therapy.

A randomized study of chemotherapy with procarbazine, vincristine, and lomustine with and without radiation therapy for astrocytoma grades 3 and/or 4.

The authors undertook a controlled, prospective, randomized study of 171 patients with supratentorial astrocytoma grades 3 and/or 4 (classified according to Kernohan). All patients were given chemotherapy consisting of procarbazine, vincristine, and lomustine (CCNU) (PVC). Half of the patients received whole-brain irradiation (RT) to a dose of 5800 cGy in the tumor-bearing hemisphere and 5000 cGy in the contralateral hemisphere. After diagnosis of progressive tumor growth, patients received individual treatment. The endpoint of the study was time to progression, but cases were followed until the patients died. Median time to progression (MTP) for the whole randomized population was 21 weeks. Median survival time (MST) was 53 weeks; 18% of patients survived for 2 years or longer. Survival analysis showed that patients less than 50 years of age treated with PVC plus RT had significantly longer MTP (81 weeks) and MST (124 weeks) than all other patients. For patients less than 50 years of age treated with PVC alone, MTP was 21 weeks and MST was 66 weeks. For patients more than 50 years of age treated with PVC plus RT, MTP was 23 weeks and MST was 51 weeks; in the PVC group, MTP was 17 weeks and MST was 39 weeks. Age, Karnofsky index, areas of Grade 2, and absence of extensive necrosis in the tumor were significant prognostic factors in the univariate analyses. Patients less than 50 years of age treated with PVC plus RT had significantly longer survival (P = 0.037) when correcting for these factors in a multi-variate analysis.

Lateral medullary infarction: prognosis in an unselected series.

We describe the acute and long-term prognosis in 43 patients with lateral medullary infarction (LMI) collected from a population-based stroke registry from 1982 to July 1988. Mean age was 63.9 years and median time of follow-up was 33 months. In the acute phase, 5 patients (11.6%) died from respiratory and cardiovascular complications and 2 new strokes occurred, both in the posterior circulation. During follow-up, recurrent vertebrobasilar territory strokes occurred in only 2 patients (a rate of 1.9% per year). The mechanisms of stroke were vertebral artery (VA) branch occlusion, causing a medial medullary syndrome, and basilar artery thrombosis propagating from a contralateral, distal VA stenosis. In the acute phase of LMI, respiratory and cardiovascular events, presumably caused by autonomic dysfunction related to the lateral medullary lesion, are the major hazards. Recurrent posterior circulation strokes were uncommon during follow-up.

Isthmic lumbar spondylolisthesis with sciatica. MR imaging vs myelography.

Seventeen patients with sciatica and isthmic lumbar spondylolisthesis were studied with magnetic resonance (MR) imaging. In 13, myelography was also performed: 5 had dural sac deformation and root sleeve shortening, 2 had deformation with unilateral root sleeve shortening, one had bilateral root sleeve shortening only, and one had sac deformation only. In 4, myelography was normal. On sagittal MR examinations the neural foramen had an altered shape bilaterally with the long axis horizontal in all cases. In addition to altered shape the following was found in the 33 foramina evaluated. I: normal nerve (n = 8); II: compressed nerve (n = 16); III: disappearance of fat, nerve not possible to identify (n = 9). In patients with unilateral sciatica, the degree of foraminal stenosis correlated well with the side of symptoms. Coronal views showed the course of the nerve and pedicular kinking. Eight patients underwent decompressive surgery which revealed nerve compression by hypertrophic fibrous tissue and pedicular kinking, which correlated well with the findings on MR. Since the site of nerve compression often was peripheral to the root sleeves, myelography did not give complete information.

A long-term prospective study of optic neuritis: evaluation of risk factors.

Eighty-six patients with monosymptomatic optic neuritis of unknown cause were followed prospectively for a median period of 12.9 years. At onset, cerebrospinal fluid (CSF) pleocytosis was present in 46 patients (53%) but oligoclonal immunoglobulin in only 40 (47%) of the patients. The human leukocyte antigen (HLA)-DR2 was present in 45 (52%). Clinically definite multiple sclerosis (MS) was established in 33 patients. Actuarial analysis showed that the cumulative probability of developing MS within 15 years was 45%. Three risk factors were identified: low age and abnormal CSF at onset, and early recurrence of optic neuritis. Female gender, onset in the winter season, and the presence of HLA-DR2 antigen increased the risk for MS, but not significantly. Magnetic resonance imaging detected bilateral discrete white matter lesions, similar to those in MS, in 11 of 25 patients, 7 to 18 years after the isolated attack of optic neuritis. Nine were among the 13 with abnormal CSF and only 2 belonged to the group of 12 with normal CSF (p = 0.01). Normal CSF at the onset of optic neuritis conferred better prognosis but did not preclude the development of MS.

Intraventricular choroid plexus "arachnoid" cyst. MRI findings.

A young women presented with chronic headaches associated with a cyst of the right lateral ventricle. The diagnosis of intraventricular so-called "arachnoid" cyst was supported by CT scan, MRI and stereotactic puncture. MRI was of great value for demonstrating that the cyst was located within the lateral ventricule, that it was delineated by a thin wall adherent to the choroid plexus and that the cyst content was CSF-like.

Comparison of myelography, CT myelography and magnetic resonance imaging in cervical spondylosis and disk herniation. Pre- and postoperative findings.

Twenty-six patients with cervical radiculopathy and/or myelopathy caused by spondylosis or disk herniation were examined with myelography, CT myelography and MR. Fourteen of the patients were operated upon and 11 of them underwent postoperative MR and CT. The three radiologic methods provided comparable information about narrowing of the subarachnoid space and compression of the spinal cord. It was more difficult to distinguish bone from soft tissue with MR only, but the combination of MR and conventional radiography gave sufficient information for this differentiation. When radiologic nerve root sheath deformity was compared with clinical radiculopathy, myelography, CT myelography and MR had similar sensitivity and accuracy. Postoperative MR could reveal remaining indentation on the thecal sac and the cord but CT without contrast medium was useful as a complement to determine the aetiology of the indentation. Because MR has several practical advantages, it is well suited as the primary imaging modality, together with conventional radiography, for the preoperative radiologic evaluation of patients with cervical radiculopathy and/or myelopathy. Postoperative MR is useful in patients with persistent or new symptoms.

Repeated cranial computed tomographic and magnetic resonance imaging scans in two cases of eclampsia.

In two cases of eclampsia with consumptive thrombocytopenia, the maximum increase in blood pressure and the lowest platelet count coincided with the maximum degree of neurologic and neuroradiologic abnormality. Computed tomograms showed decreased attenuation, and T2-weighted magnetic resonance images showed increased signal intensity focally in the cerebral cortex and the deep gray and white matter. Blood pressure, platelet count, clinical status, and roentgenograms normalized completely in both cases. Severe arterial hypertension and disseminated transitory microvascular occlusions presumably caused multiple small foci of brain edema that resolved without remaining detectable ischemic brain damage.

Clinical and radiologic features of lacunar versus nonlacunar minor stroke.

We determined the angiographic presence of extracerebral and intracerebral arterial disease in 122 patients with minor stroke within the carotid territory; we excluded patients with a recognized cardiac source of emboli. Based on clinical features and computed tomographic findings, patients were classified as having lacunar infarcts (n = 61), nonlacunar infarcts (n = 53), and infarcts of indeterminate type (n = 8). Severe carotid bifurcation disease (greater than or equal to 50% stenosis or occlusion) was significantly more common in nonlacunar than in lacunar infarcts, on both the ipsilateral (p less than 0.001) and the contralateral (p less than 0.01) sides; 79% of the patients with nonlacunar infarcts had severe carotid bifurcation and/or middle cerebral artery disease on the ipsilateral side compared with 3.3% of the patients with lacunar infarcts. Our data underscore the need for classification of patients by the underlying mechanisms in future studies of treatment of ischemic stroke.

MR imaging of the cervical spine in rheumatoid arthritis.

The cervical spine was examined with MR imaging and conventional radiography in 23 patients with severe rheumatoid arthritis. All patients had neck pain and 17 also had neurologic symptoms. MR provided detailed information about soft-tissue lesions, vertebral dislocation, and narrowing of the spinal canal. Pannus surrounding the odontoid process was revealed in 14 patients, all with horizontal atlantoaxial subluxation. Compression of the medulla and/or spinal cord, caused by dislocated vertebrae and/or the soft-tissue mass around the odontoid process, was seen in 15 patients. When there was more than one dislocation the most important level could be determined. Posterior occipitocervical fusion had been performed in six of the patients, and in only two of these was adequate analysis of the upper cervical spine impossible because of artifacts from metal (stainless steel wires and pins). Sagittal MR in the neutral position combined with conventional radiography, including lateral views in flexion and extension, provided all the information necessary for further clinical management of rheumatoid arthritis of the cervical spine.

Emergency magnetic resonance examination of patients with spinal cord symptoms.

Eighteen consecutive patients with spinal cord symptoms of sudden or relatively sudden onset were examined with magnetic resonance imaging (MRI). The examinations were performed on a 0.3 tesla permanent/resistive imaging system using solenoidal surface coils. MRI revealed epidural tumour in five patients, intramedullary tumour in one, epidural abscess in one, myelitis in two, spontaneous intraspinal epidural haematoma in two, disc herniation in two, traumatic lesions in four and no abnormality in one patient. MRI was found to be capable of non-invasively and painlessly detecting and exactly defining the extent of intraspinal and paraspinal lesions. In some cases the nature of the lesion could be inferred from specific signal characteristics, which is a unique property of MRI. The results strongly suggest that MRI is superior to myelography and other imaging methods and should be regarded as the examination of choice in the emergency examination of patients with spinal cord symptoms.

Arterial occlusion due to Listeria meningoencephalitis in an immunocompromised boy.

Sequential CAT scan studies of the brain were performed in a 7-year-old boy with Listeria monocytogenes serotype 1 meningoencephalitis. The infection occurred while he was receiving maintenance chemotherapy for T-cell non-Hodgkin lymphoma. A lesion in the right hemisphere during the infection resulted in an excessive enlargement of the right ventricle 10 months later, most probably caused by arterial occlusion.

Regional differences in the proton magnetic resonance relaxation times T1 and T2 within the normal human brain.

The proton magnetic resonance (MR) relaxation times T1 and T2 were determined in autopsy specimens from 13 different regions of normal human brains. One hundred and seventy-four tissue samples from 25 brains were examined in a pulsed MR analyzer of 0.25 T and were then also studied histologically. There were regional differences in T1 and T2 within the cerebral gray matter but not within the white matter. These regional differences might reflect the different composition and cytoarchitectonic structure of the cortical regions and should be taken into consideration in the interpretation of cortical lesions on MR images.

Young stroke patients. An angiographic study.

In 59 young stroke patients without predisposing conditions (thromboembolic mechanisms, diabetes, cardiac disease, coagulation disturbances), the angiographic findings and the clinical observations in combination make arterial dissection the most probable diagnosis in 45 patients. In an additional 7, this diagnosis remains as a possible diagnosis. It is suggest that in patients under 40 years of age with no predisposing disease and with sudden onset of neurologic deficits, preceded or accompanied by headache and/or neck pain and often associated with physical strain, arterial dissection should be regarded as the most likely diagnosis.

Postoperative CT findings in acoustic neurinomas operated upon by a translabyrinthine approach.

The findings at CT examinations, performed on 46 patients with acoustic neurinomas about 6 months after translabyrinthine surgery, were analyzed and compared with preoperative findings. Direct as well as indirect signs of expansion had disappeared postoperatively. Bulging of cerebellar tissue towards the operative defect in the petrous bone, a finding not connected with local adhesions, was notable. Hypodensity in the vicinity of the removed tumor occurred either due to local widening of the subarachnoid space or due to changes within the cerebellar parenchyma. Local and general widening of the fourth ventricle as a sign of atrophy was a frequent finding.