Pantothenate kinase-associated neurodegeneration (PKAN) in a child with Down syndrome. A case report and follow-up with MRI.

Neurodegeneration with brain iron accumulation (NBIA) is a subtype of inherited metabolic disorders. It includes pantothenate kinase-associated neurodegeneration (PKAN), which is a rare autosomal recessive disorder caused by the mutation of pantothenate kinase 2-gene (PANK2). It affects the deep grey matter nuclei causing progressive extrapyramidal motor impairment.1 We present a case of genetically proven PKAN in a child with mosaic trisomy 21 in which T2- hyperintensity of the basal ganglia was seen followed by the classic eye-of-the-tiger sign in a follow-up MRI.

Transarterial chemoembolization of liver metastases in patients with uveal melanoma.

Metastases from uveal melanoma are often confined to the liver. Palliative hepatic chemoembolization has been considered to be a reasonable treatment approach. We enrolled 14 patients with hepatic metastases from uveal melanoma into a pilot trial of transarterial chemoembolization (TACE). All patients received additional systemic immuno-chemotherapy or best supportive care. In 31 procedures 100mg/m(2) of cisplatine was continuously infused by means of a power injector preceding embolization by manual injection of polyvinyl alcohol particles. In three procedures cisplatine was replaced by 200mg/m(2) carboplatine because of increased serum creatinine levels. Tumor response was evaluated using RECIST criteria. Fourteen patients received 34 TACE's (mean: 2.4 treatments). Eight patients (57%) achieved partial response (PR), four patients (29%) had stable disease and two patients (14%) tumor progression. Median time to progression was 8.5 months (5-35 months). Median survival after first TACE was 14.5 months in responders compared to 10 months in non-responders (p=0.18, not significant) and 11.5 months (3-69 months) in all patients. In seven patients with metastases occupying less than 25% of liver volume median survival was 17 months compared to 11 months in seven patients with tumor involvement of more than 25% (p=0.02) with partial response rate of 86% and 29%, respectively. TACE of liver metastases from uveal melanoma is well tolerated and may prolong survival in patients with limited tumor extension.

Prospective investigation of autonomic cardiac neuropathy in diabetes mellitus.

Forty-five patients with clinically manifest diabetes mellitus were investigated (25 male, 20 female, 48 +/- 10 yrs, 14 diabetes type 1, 31 type 2). Duration of manifestation was 12.2 +/- 9.7 yrs.Vibration thresholds and thermal thresholds were assessed. Respiratory sinus arrhythmia (RSA) was measured during deep respiration at 6/min. The QTc-interval was assessed according to Bazett's formula. MIBG-SPECT was carried out in all 45 cases. Patients with abnormal MIBI perfusion scintigraphy had previously been excluded from the study. RSA was abnormal in 12/45 patients. The MIBG-SPECT was abnormal in 28/45 cases with dorso-septal lack of activity. No difference was seen between type 1 and 2 diabetics with regard to either vibration and thermal thresholds or RSA and MIBG-SPECT. Abnormal MIBG-SPECT was correlated with vibration threshold and abnormal heart RSA tests but not with abnormality in QTc. The mean QTc-interval was 419 +/- 24 ms (QTc normal in 36, abnormal > or = 440ms in 9). It was longer in female than in male patients. There exists no significant correlation of QTc-interval results with either heart rate variability or MIBG-SPECT. The QTc-interval is not a sensitive parameter of autonomic cardiac denervation.

[Dynamic cranial CT in ischemic cerebral lesions]. / Dynamische Schädel-CT bei ischämischen Grosshirnläsionen.

58 patients with recent transient or permanent neurologic deficits of with proven carotid stenoses were examined by dynamic CT at the level of the internal capsule. In the presence of cerebral infarcts there was marked delay in the time/density curve with reduced peaks. Abnormal perfusion could be demonstrated by early examinations before definite morphological changes were seen. With transient ischaemic attacks there were no significant changes in perfusion; in the presence of carotid stenoses the results were variable. The perfusion abnormalities in the hemispheres shown by dynamic cranial CT could be confirmed to some extent by 99mTc-HMPAO-SPECT.

[Problems in recognizing recurrences of craniocervical malignancies in CT]. / Probleme der Rezidiverkennung kraniozervikaler Malignome im CT.

A retrospective study was carried out involving 39 patients with malignant tumours of the head and neck in order to differentiate by CT changes due to local tumour or lymph node recurrences and various post-operative or post-irradiation changes. In these patients, two or more CT examinations of the neck were available, derived from a fourth generation scanner. The suspected lesions were classified according to their type and the appearances correlated with the treatment and clinical findings. There was frequent overlap between the appearances of benign and malignant changes, so that in individual cases a definite decision often proved impossible.

Cranial CT artifacts and gantry angulation.

Computed tomographic investigation of the brain is frequently accomplished by scanning parallel to the canthomeatal line. In these scans, evaluation of the brain stem and neighboring structures is often compromised by streak artifacts from bone-induced beam hardening. These artifacts may be reduced by introducing a change in gantry angulation. Results from a phantom study as well as from a clinical trial offer evidence that may be helpful in assessing different scanning planes. An inclination of 5 degrees below Reid baseline is suggested to minimize the interpetrous artifact. Variations in slice thickness and exposure parameters do not appear to affect significantly this typical posterior fossa artifact.

Myelin basic protein immunohistochemistry: a study of the early stages of myelination in the brainstem of the rat.

An immunohistochemical study of MBP distribution in the brainstem of neonate till 16 d old rats based on the peroxidase-antiperoxidase method is described. Axons already invested with immunoreactive sheaths were found in neonate rats in the ventral funiculus of the cervical spinal cord and in the medial longitudinal fascicle of the medulla oblongata. Fibres commencing with myelination showed a closely spaced array of varicosities in longitudinal sections which diminished gradually. A caudo-rostral decrease in density of myelinated fibres in the brainstem was found in the medial and dorsal longitudinal fascicles. In contrast to other pathways, myelination in the fibres of the corticospinal tract in the brainstem occurred in a strictly synchronized pattern. The same temporal pattern of myelination was also observed in the cervical corticospinal tract, except that a few myelinated fibres had been visible much earlier within the area of the tract. At the exit of cranial nerves, the transitorial zone from central to peripheral myelin was outlined by a decrease in immunostaining.

The sequence of myelination in the brainstem of the rat monitored by myelin basic protein immunohistochemistry.

The temporal order which is observed by nervous pathways in their myelination was investigated in the brainstem of neonatal to 16-day-old albino rats. The immunohistochemical detection of myelin basic protein in newly forming myelin sheaths provided a highly sensitive and specific criterion to judge the time of onset and the progress of myelination in its initial stages. Immunohistochemistry was performed on paraffin-embedded tissue according to the unlabeled peroxidase-antiperoxidase method. A small number of immunoreactive fibers was already present in neonate rats in the ventral funiculus of the cervical spinal cord and in the medial longitudinal fascicle of the medulla oblongata. By the 4th postnatal day myelination had commenced in many sensory tracts and in the trigeminal root, in the tectospinal tract, in the inferior cerebellar peduncle and in the roots of most cranial motor nerves. The auditory pathway up to the inferior colliculus, the gracile, spinocerebellar and rubrospinal tracts and the superior cerebellar peduncle had acquired some myelin on the 7th day. Phylogenetic late fiber systems also appeared to myelinate comparatively late: the transverse pontine fibers and the medial cerebellar peduncle started on the 10th day, and in the corticospinal tract a conspicuously synchronized myelination appeared on the 13th day. All pathways of the brainstem possessed myelinated fibers on the 16th day and some tracts had approached their relative maturity.

The competitive antigen spot test (CAST). A rapid and simple means of quantitatively screening antisera.

A method is described which permits the simultaneous testing of several antisera and an estimation of their antigen binding capacities. The sera to be tested are preabsorbed with different quantities of antigen and subsequently assayed for unbound antibodies by a second incubation with antigen immobilized on nitrocellulose. When the absorbing antigen exceeds a definite concentration, which is specific for a particular antiserum, a clear cut-off is observed when immunostaining is used in the following step. This competitive antigen spot test (CAST) is both quick and easy to perform and was found useful when comparing different antisera.