[A rare manifestation of sarcoidosis]. / Seltene Manifestation einer Sarkoidose.

This article reports the case of a 14-year-old boy who was presented in the case conference with symptoms of decreased visual acuity, scintillating scotomas and photophobia. Physical examination revealed right facial paralysis, parotid gland swelling, high fever and poor general condition. Ophthalmoscopy revealed anterior and posterior uveitis including macular edema and chorioretinal infiltrates. Angiography revealed a dense pattern of hyperfluorescent lesions and these observations resulted in the diagnosis of Heerfordt syndrome. Under systemic prednisolone therapy, symptoms were reduced and visual acuity recovered.

Gray value differences to dentin of root posts radiographed with digital intraoral systems and conventional X-ray films.

This study compared the gray value differences to dentin of titanium and FRC root posts in anterior and posterior teeth radiographed with digital intraoral systems and conventional x-ray film. Radiographic images (n=5) of titanium or fiber-reinforced composite (FRC) root posts placed in extracted teeth were taken with six digital intraoral radiographic devices and conventional x-ray film (control group). Gray value differences were evaluated between the root posts and root dentin. Statistical analyses of the results were performed with three-way and one-way ANOVA with Bonferroni-Dunn's multiple comparisons post-hoc analyses (α=0.05). Significantly higher gray value differences of titanium and FRC posts were found in anterior teeth but not in molars for XIOS, Sidexis and Visualix digital intraoral systems, but not for RVG, DenOptix and VistaScan (FRC posts). Except for DenOptix with incisors and molars and VistaScan with molars, conventional x-ray films showed significantly lower gray value differences of titanium posts in incisors and molars compared to the corresponding digital radiographs.

Left-hemispheric dominance for articulation: a prospective study on acute ischaemic dysarthria at different localizations.

Dysarthria is a frequent symptom in cerebral ischaemia. However, speech characteristics of these patients have not previously been investigated in relation to lesion site in a prospective study. We investigated the auditory perceptual features in 62 consecutive patients with dysarthria due to a single, non-space-occupying cerebral infarction confirmed by MRI. Standardized speech samples of all patients were stored within 72 h after stroke onset using a digital tape recorder. Speech samples were assessed independently by two experienced speech therapists, who were unaware of the clinical and neuroradiological findings, using an interval scale ranging from 0 to 6. Separately assessed were features of articulation, phonation, prosody, and the global severity for a total of 31 items. Extracerebellar infarctions (85.5%) were located in the lower motor cortex (14.5%), striatocapsular region (46.8%) and base of the pons (24.2%). Isolated cerebellar infarctions were present in 14.5% of patients. There was a strong correlation between the findings of both examiners, showing identical scores, or only minor differences (<1 on the assessment scale) for 80% of all items. The average severity of dysarthria was 2.9 +/- 1.3. Articulatory abnormalities were the predominant deviation characteristics, affecting in particular the production of consonants. However, phonatory and prosodic abnormalities were also frequently observed speech characteristics. As revealed by factor analysis of speech characteristics the total severity of dysarthria was mainly influenced by the impairment of articulation. Speech parameters describing characteristics of articulation and prosody showed significant side-to-side and area differences, while this effect was lacking for any voice parameter. Left cerebral lesions showed a more severe overall impairment of speech and articulation, independent of lesion topography. Thirty-eight of 62 patients were available for follow-up. Speech evaluation showed normal speech within weeks in 15 out of 38 patients (39.5%). In the other 23 patients overall severity of dysarthria was mild. This is the first prospective study which describes speech characteristics of dysarthria due to acute unilateral cerebral infarctions. We could demonstrate that dysarthria in extracerebellar infarctions was more frequently caused by left-sided lesions and that the severity of dysarthria was more pronounced in left-sided lesions independent from lesion topography. All extracerebellar lesions were located along the course of the cortico-bulbar tract fibres. Compatible with a common pathophysiological basis of dysarthria in these patients, none of the 31 speech items differed significantly between subcortical and brainstem lesions.

Sensitivity of transcranial magnetic stimulation of cortico-bulbar vs. cortico-spinal tract involvement in Amyotrophic Lateral Sclerosis (ALS).

BACKGROUND: An upper motor neuron (UMN) lesion in amyotrophic lateral sclerosis (ALS) is often difficult to identify because clinical signs may be discrete or masked by severe simultaneous LMN lesions. We compared the diagnostic sensitivity of transcranial magnetic stimulation (TMS) to cranial muscles and limb muscles in the detection of UMN lesions. DESIGN: We investigated corticobulbar and corticospinal tract function to the tongue/orofacial muscles and abductor digiti minimi/tibial anterior muscles with TMS in 51 patients with ALS to compare the diagnostic yield in the detection of UMN dysfunction. An UMN lesion was assumed when the following were found: the peripheral conduction time and amplitude of the M-wave were within the normal range, the response to cortical stimulation was absent, the TMS evoked/M-wave amplitude ratio was reduced, and the central motor conduction time or the interside difference was delayed (> mean+2.5 SD). RESULTS: On the basis of these criteria a UMN lesion to the orofacial muscles was identified in 24 patients (47%), to the tongue in 27 (53%), and to the upper and lower limbs in 13 (25%) and 22 patients (43%), respectively. Combined abnormalities from all sites increased the diagnostic yield to 39 patients (76%). TMS of the limb muscles confirmed a UMN lesion in only 15 (54%) of the 28 patients with clinically confirmed UMN involvement. This number increased to 23 patients (82%) if tongue and orofacial muscles were taken into acount. CONCLUSION: Our results indicate the early and in most cases subclinical corticobulbar tract involvement of the central motor pathways to the orofacial muscles and tongue in ALS. TMS of the tongue and orofacial muscles had a higher sensitivity in identifying UMN lesions than that of the upper and lower limbs.

The course of corticofacial projections in the human brainstem.

Transcranial magnetic stimulation was used to investigate the corticofacial projections in 53 patients with (n = 28) and without (n = 25) central facial paresis due to unifocal ischaemic lesions at different brainstem levels. Lesion topography documented by MRI studies was correlated with the electrophysiological findings. In the majority of patients the corticofacial fibres travel within the ventromedial base of the pons and cross the midline at the level of the facial nucleus. In some individuals, however, we found evidence that corticolingual fibres form an 'aberrant bundle' in a paralemniscal position at the dorsal edge of the pontine base. In other patients the corticofacial fibres loop down into the ventral part of the upper medulla, cross the midline and ascend in the dorsolateral medullary region ipsilaterally to the facial nucleus. The findings suggest that facial paresis due to a brainstem lesion may present as contralateral supranuclear facial paresis by a lesion of the cerebral peduncle, pontine base, the aberrant bundle and the ventral medulla. Supranuclear facial paresis ipsilateral to the lesion side may result from a lesion in the lateral medulla, and facial paresis of the supranuclear type may be imitated by a lesion of the peripheral facial nerve in the dorsolateral medulla with involvement of the lower pons.

Dysarthria in acute ischemic stroke: lesion topography, clinicoradiologic correlation, and etiology.

BACKGROUND AND PURPOSE: Although dysarthria is a frequent symptom in cerebral ischemia, there is little information on its anatomic specificity, spectrum of associated clinical characteristics, and etiologic mechanisms. METHODS: An investigation of 68 consecutive patients with sudden onset of dysarthria due to a single infarction confirmed by MRI or CT was conducted. RESULTS: Dysarthria was associated with a classic lacunar stroke syndrome in 52.9% of patients. Isolated dysarthria and dysarthria-central facial and lingual paresis occurred in 2.9% (n = 2) and 10.3% (n = 7), respectively. Dysarthria-clumsy hand syndrome was observed in 11.7% (n = 8) of patients and associated with pure motor hemiparesis and/or ataxic hemiparesis in 27.9% (n = 19). The lesions were due to small-vessel disease in 52.9% (n = 36), to cardioembolism in 11.8% (n = 8), and to large-vessel disease in only 4.4% (n = 3) of cases. Infarctions were located in the lower part of the primary motor cortex (5.9%; n = 4), middle part of the centrum semiovale (23.5%; n = 16), genu and ventral part of the dorsal segment of the internal capsule (8.8%; n = 6), cerebral peduncle (1.5%; n = 1), base of the pons (30.9%; n = 21), and ventral pontomedullary junction (1.5%; n = 1). Isolated cerebellar infarctions affected the rostral paravermal region in the superior cerebellar artery territory. CONCLUSIONS: Extracerebellar infarcts causing dysarthria were located in all patients along the course of the pyramidal tract. This finding correlates with the frequent occurrence of associated pyramidal tract signs in 90.7% (n = 62) of patients. Isolated cerebellar infarcts leading to dysarthria were in all cases located in the territory of the superior cerebellar artery.

[Not Available]. / Topodiagnostik ischämisch bedingter Dysarthrophonien.

In a prospective study we investigated 106 consecutive patients with sudden onset of dysarthria due to a single, not space-occupying infarction confirmed by MRI. Extracerebellar infarctions (81.1%) were located in the lower part of the primary motor cortex (3.8%), middle part of the centrum semiovale (23.6%), striatocapsular (5.7%), genu and dorsal segment of the internal capsule (11.4%), cerebral peduncle (0.9%), ventral ponto-mesencephalic region (1.9%), base of the pons (23.8%), and the ventral pontomedullary junction (1.9%). Isolated cerebellar infarctions affected the rostral paravermal region in the SCA-territory. Combined extracerebellar and cerebellar infarctions were present in 10.4% of our patients. In extracerebellar infarctions the lesions were more often localized in the left hemisphere as compared with the right hemisphere (77.5% vs 22.5%). Cerebellar infarctions, however, affected the right side in 4 and the left side in 2 patients.Correlating to clinical, electrophysiological, and fMRI-findings, the lesion topography of extracerebellar infarctions underlying dysarhria is consistent with an impairment of volitional movements due to a lesion of the corticobulbar pathways while cerebellar lesions result in impaired coordination of articulatory movements.

Ipsilateral facial weakness in upper medullary infarction-supranuclear or infranuclear origin?

We describe two patients with upper medullary infarctions showing ipsilateral facial weakness and relative sparing of the upper facial muscles. Electrophysiological follow-up using transcranial magnetic stimulation of the motor cortex in combination with stimulation of the peripheral facial nerve disclosed a supranuclear (corticofacial) tract lesion in one patient and a partial nuclear/infranuclear intra-axial facial nerve lesion in another.

Isolated dysarthria due to extracerebellar lacunar stroke: a central monoparesis of the tongue.

OBJECTIVES: The pathophysiology of dysarthria can preferentially be studied in patients with the rare lacunar stroke syndrome of "isolated dysarthria". METHODS: A single study was carried out on seven consecutive patients with sudden onset of isolated dysarthria due to single ischaemic lesion. The localisation of the lesion was identified using MRI. The corticolingual, cortico-orofacial, and corticospinal tract functions were investigated using transcranial magnetic stimulation. Corticopontocerebellar tract function was assessed using 99mTc hexamethylpropylene amine oxime-single photon emission computerised tomography (HMPAO-SPECT) in six patients. Sensory functions were evaluated clinically and by somatosensory evoked potentials. RESULTS: Brain MRI showed the lesions to be located in the corona radiata (n=4) and the internal capsule (n=2). No morphological lesion was identified in one patient. Corticolingual tract function was impaired in all patients. In four patients with additional cortico-orofacial tract dysfunction, dysarthria did not differ from that in patients with isolated corticolingual tract dysfunction. Corticospinal tract functions were normal in all patients. HMPAO-SPECT showed no cerebellar diaschisis, suggesting unimpaired corticopontocerebellar tract function. Sensory functions were not affected. CONCLUSION: Interruption of the corticolingual pathways to the tongue is crucial in the pathogenesis of isolated dysarthria after extracerebellar lacunar stroke.

Isolated voluntary facial paresis due to pontine ischemia.

We describe a patient with isolated voluntary facial paresis due to a unilateral lacunar lesion in the contralateral mediodorsal middle base of the pons. Transcranial magnetic stimulation confirmed the involvement of supranuclear corticofacial tract fibers and sparing of the corticolingual and corticospinal connections. This observation demonstrates that the fibers conveying voluntary orofacial activation descend mediodorsally at the level of the middle pons and that the fibers conveying emotional activation may be assumed to converge below this level.

The effects of amino acids on albumin synthesis by the isolated perfused rat liver.

Albumin synthesis was measured in the isolated perfused rat liver by using the livers of both well-fed and starved rats. Starvation markedly decreased albumin synthesis. The livers from starved rats were unable to increase synthesis rates after the addition to the perfusates of single amino acids or the addition of both glucagon and tryptophan. Arginine, asparagine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, threonine, tryptophan and valine, added together to ten times their normal peripheral blood concentrations, restored synthesis rates to normal. The plasma aminogram (i.e. the relative concentrations, of amino acids) was altered by depriving rats of protein for 48h. The use of blood from the deprived rats as perfusate, instead of normal blood, decreased albumin synthesis rates significantly by livers obtained from well-fed rats. The addition of single amino acids, including the non-metabolizable amino acid, alpha-aminoisobutyric acid, to the above mixture increased albumin synthesis rates to normal values. It is concluded that amino acids play an important role in the control of albumin synthesis and that more than one mechanism is probably involved.

Secondary hyperparathyroidism in osteomalacia.

Twenty-one patients with histologically proved osteomalacia from various causes were investigated for biochemical and radiological evidence of osteomalacia and secondary hyperparathyroidism. Among the 15 who maintained a normal serum calcium, seven had a raised phosphate excretion index, seven had a raised serum alkaline phosphatase, and six had phalangeal erosions. On the other hand, six patients had a subnormal serum calcium; of these, none showed a raised phosphate excretion index, one had a raised serum alkaline phosphatase, and one had erosions. The phosphate excretion index and the alkaline phosphatase were strongly correlated (r = +0.84). It is concluded that this absence of manifest secondary hyperparathyroidism in some patients with osteomalacia is due to failure of an increase in the release of parathyroid hormone. Measurement of phosphaturia does not appear to be a useful means of detecting osteomalacia. Subsequently, the 24-hour (stable) strontium space measurement was found to be the most sensitive single biochemical screening test for osteomalacia.