A model of the dual effect of gadopentetate dimeglumine on dynamic brain MR images.

An optimized dynamic gradient echo sequence with two echoes is used to obtain data that can be analyzed with indicator dilution theory as well as with pharmacokinetic theory. Taking advantage of the simultaneity of T(*)(2) and T(1) information, both theories can be employed and merged to interpret consistently the observed effects of the redistribution of a contrast agent (gadopentetate dimeglumine) into the tissue from first pass onward. The regional cerebral blood volume (rCBV) and the exchange rate of the contrast agent between the vascular and the interstitial space through the blood-brain barrier are analyzed for each pixel in a two-step algorithm. Two values for rCBV are obtained with different weighting for the microvascular fraction of the blood volume. Because the analysis, called PELEAKAN, is capable of separating effects related to perfusion (through intravascular blood volume) and to leakage in places where the blood-brain barrier is damaged, it is an appropriate tool for evaluating these parameters in brain tumors, and we show clinical examples of this analysis in brain tumor patients.

Artifact in SE phase images can mimic aortic dissection.

Phase images of cardiac-triggered thoracic spin-echo scans can present an artifactual border-like feature across the aorta. This may be misinterpreted as a dissection. The artifact results from helical flow in the aorta; cause and appearance of the artifact are discussed.

The prognostic value of cortical magnetic stimulation in acute middle cerebral artery infarction compared to other parameters.

The prognostic value of magnetic evoked potentials (MEP), somatosensory evoked potentials (SSEP), age and radiological parameters was determined in 50 patients with acute middle cerebral artery infarction. We performed MEP and SSEP within 4 days and after 6 weeks and 3 months of the infarction and assessed clinical improvement by using the Barthel index (BI) and the Rankin scale. The localization and extent of the infarction was investigated by CT scanning or NMR. All parameters were correlated to clinical outcome and the prognostic significance of each parameter in addition to BI was determined. MEP, SSEP, and age were valuable prognostic parameters in predicting stroke outcome when used together with the BI. However, in stepwise regression analysis using all parameters simultaneously, only MEP and age significantly contributed to clinical outcome in addition to BI. Patients showed a better outcome when their MEP was normal or delayed, measured within 4 days of the infarction, compared to patients with absent MEP. Clinical outcome was better at a younger age.

A Dutch family with benign hereditary chorea of early onset: differentiation from Huntington's disease.

A large Dutch family of 88 members, running through five generations, is described with benign hereditary chorea of early onset. The clinical presentation was heterogeneous. The chorea manifested in late infancy or childhood, interfered with writing, was non-disabling, stable or even improved in adulthood in most cases, but was slowly progressive with gait impairment in some. There was mild dysarthria and normal intelligence. EEG brain CT-scanning and MRI were normal. Huntington's disease was excluded by analysis of the I T 15 gene, which showed a normal number of the CAG trinucleotide repeats in two patients. It is concluded that benign hereditary chorea of early onset is an entity different from Huntington's disease and that in cases of early onset chorea the diagnostic accuracy is markedly improved by DNA testing.

MR assessment of the normal position of the spinal cord in the spinal canal.

PURPOSE: To investigate intradural geometry, which strongly influences the effects of epidural spinal cord stimulation. METHODS: Axial MR images with turbo spin-echo were made of 26 healthy subjects at C-4 through C-6, T-5 and T-6, and T-11 and T-12, at T-11 and T-12 both in the supine and the prone position. Measurements were made of the dorsomedial and the ventromedial cerebrospinal fluid layer and the anteroposterior and transverse sizes of both the spinal cord and the dural sac. The samples of all variables were analyzed statistically. The distance between spinal and vertebral midline was also determined. RESULTS: The dorsal cerebrospinal fluid layer was 1.5 to 4.0 mm at C-4 through C-6 and 4.0 to 8.5 mm at T-5 and T-6. At T-11 it was 2.0 to 6.0 mm in the supine position and was increased by approximately 2.2 mm in the prone position. At T-12 these values were 1.5 to 4.5 mm and approximately 3.4 mm, respectively. Differences between the spinal and vertebral midline up to 1.5 to 2.0 mm occurred in approximately 40% of the images. CONCLUSIONS: Because there are variations of the dorsal cerebrospinal fluid layer among subjects by more than a factor of 2, and significant variations of the mediolateral position of the spinal cord, information on these parameters in patients will be essential for the optimal application of epidural spinal cord stimulation.

Congenital cervical spinal muscular atrophy: a non-familial, non progressive condition of the upper limbs.

Two patients with congenital cervical spinal muscular atrophy had symmetrical severe muscle weakness and wasting confined to the upper limbs, areflexia and congenital contractures. The shoulders were internally rotated, elbows extended and wrists flexed. There were no sensory or bulbar symptoms, scoliosis, long tract signs or lower limb involvement. This condition should be regarded as a neurogenic type of arthrogryposis, limited to the upper limbs.

SPECT, CT and MRI in a Turkish family with Huntington's disease.

A Turkish family with Huntington's disease documented on CT, MRI and SPECT is reported. Whereas in clinically definite cases CT and MRI are of limited value and SPECT does not add anything of value, in one asymptomatic subject SPECT showed moderate caudate nucleus hypoperfusion, underlining the hypothesis that SPECT may have a role in predicting Huntington's disease.

Is there involvement of the central nervous system in hereditary sensory radicular neuropathy?

There is pathological evidence that hereditary sensory radicular neuropathy (HSN type I) is a disorder related to multi-system atrophy with marked cell loss in the cerebral cortex, thalamus, brain stem and cerebellum. We report here a clinical study of a case of HSN-I including audiometric testing, autonomic functions, electromyography, transcranial magnetic stimulation and magnetic resonance imaging of the brain. There were no signs of central nervous system involvement. It is stated that HSN-I remains a disorder of dorsal root ganglia and sensory nerves, leading to painless perforating ulceration and mutilation, within the course of the disease peripheral motor nerve involvement, but without involvement of central motor pathways.

Familial, alternating Bell's palsy with dominant inheritance.

In this paper we present a study of 6 cases, running through three generations of a Dutch family, with alternating Bell's palsy in an autosomal dominant mode of inheritance. The study included medical history data, neurological examination, blood glucose tests, electromyography, orbicularis oculi reflexes and radiological investigation. In 3 cases a bilateral hypoplasia or scanty cellularization of the mastoid bone and a unilateral obtuse tip of the petrous part of the temporal bones were found. These findings may be a potential inherited etiologic factor.

Primary diagnosis of gynecological tumors by ultrasonography and computed tomography.

In 33 patients with a pelvic mass or otherwise suspected to have gynecological malignancy, ultrasonography and computed tomography of the abdomen were performed. The results were compared afterward with the findings at operation. With both methods the nature of the tumor had been predicted correctly in the majority of cases. Localization and metastases were more frequently detected by computed tomography. Both tests appeared, in a way, to be complementary. There were no false-negative findings in both sonography and computed tomography. In three cases false-positive results were seen with both techniques.