[Long-term course of patients in neurological rehabilitation Phase B. Results of the 6-year follow-up in a multicenter study]. / Langzeitverlauf von Patienten der neurologischen Rehabilitation Phase B. Ergebnisse der 6-Jahres-Nachuntersuchung einer Multicenterstudie.

BACKGROUND: After conclusion of emergency care for severe neurological diseases patients in Germany are admitted at an early stage to so-called Phase B rehabilitation. No studies have been carried out on the long-term course of these patients. PATIENTS AND METHODS: In a prospective study in 2002 patients in Phase B from 9 centers were included and follow-up investigations were carried out after 5 and 6 years. Assessment instruments used were the Barthel index, the Rankin scale and the EQ-5D. Factors for the risk of a poor outcome and the chances for a good outcome were evaluated using multivariate logistic regression. RESULTS: A total of 1,280 patients were included in the study. A high age increased the risk of dying with a hazard quotient (HQ) of 1.05 (95% CI: 1.04-1.06) and high point counts in the coma remission scale (HQ 0.93; 95% CI: 0.92-0.96) and Barthel index (HQ 0.97; 95% CI: 0.97-0.98) on discharge reduced the risk of dying after 5 years. The factors swallowing impairment (OR 3.1; 95% CI: 1.7-5.5) and obligatory surveillance at the end of rehabilitation (OR 3.2; 95% CI: 1.2-8.6) increased the risk of a poor result in the Rankin scale 2-4 and the factors communication disorder (OR 5.0; 95% CI: 2.0-12.8) and PEG (percutaneous endoscopic gastrostomy) (OR 19.7; 95% CI: 2.7-144.4) on discharge increased the risk of a reduced health-related quality of life (defined as EQ-5D VAS <70) after 6 years. CONCLUSIONS: If support for bodily functions can be successfully reduced during Phase B rehabilitation, the patients will have a good outcome with respect to 5-year survival. If this is not successful the outcome is unfavorable with respect to survival and with respect to achieving self-sufficiency and health-related quality of life after 6 years.

Raphe nucleus of the pons containing omnipause neurons of the oculomotor system in the monkey, and its homologue in man.

Omnipause neurons take part in the generation of saccadic eye movements. They lie around the midline in the caudal pontine reticular formation, in an area usually ascribed to the nucleus raphe pontis (rp). In this study of the monkey (Macaca fascicularis and M. mulatta), we describe four series of experiments aimed at establishing that omnipause neurons lie within a distinctive cytoarchitectonic entity, which we call the nucleus raphe interpositus (rip): (1) cytoarchitectural study, (2) recording-lesion experiments to establish in which cell group omnipause neurons lie, (3) cytochrome oxidase distribution in the omnipause region and neighboring structures, and (4) neuroanatomical tracing experiments to demonstrate afferents to the omnipause region. In the detailed cytoarchitectural study of the midline structures in the caudal pons and rostral medulla, a distinctive group of neurons (rip) adjoining the ventrocaudal border of rp and dorsal to the nucleus raphe magnus (rm) is described. The striking features of rip are the uniformly arranged, narrow row of the cells either side of the midline, and the extensive horizontally oriented dendritic trees of its neurons. The abducens rootlets (NVI) pass through the reticular formation at the same rostrocaudal level as rip and form a reliable landmark for its location. Cytochrome-oxidase-stained sections demonstrated additional differences between rip and adjacent cell groups: in rip the neurons and their extensive dendrites stained strongly, but not the surrounding neuropile, whereas in rp both the neurons and the neuropile stained darkly, so that individual neurons were difficult to see. Unlike rp, rip coincides with the location of omnipause neurons, and lesions marking the sites of individual omnipause units lay within its boundaries. Tritiated leucine was injected into superior colliculus (sc), which is known to have monosynaptic connections with omnipause neurons. Labelled axons and patterns of silver grains taken to indicate the presence of terminal branching were found in and around rip, but no significant labelling was seen in rp or rm. It is concluded that the omnipause neurons lie within the rip in the monkey. These functional and morphological differences between rip and the adjacent raphe nuclei are used to justify its characterization as an independent cell group in the monkey. In order to relate these findings to man, cytochrome oxidase experiments were carried out on the human brainstem, and the pattern of staining at the level of the abducens rootlets was correlated with the cytoarchitecture.(ABSTRACT TRUNCATED AT 400 WORDS)

Responses of single neurons in the parietoinsular vestibular cortex of primates.

1. Neurons activated by stimulation of the horizontal and/or vertical vestibular semicircular canals were recorded in the parietoinsular vestibular cortex in four awake Java monkeys (Macaca fascicularis) and three squirrel monkeys (Saimiri sciureus). Steady tilt in darkness or during illumination of a vertically striped cylinder or of the normal laboratory surroundings did not lead to a significant change in PIVC neuron activity. Thus vestibular input to this cortical region seems to be restricted to signals originating in the semicircular canal receptors. 2. Vestibular stimulation in the three main experimental planes (roll, yaw, and pitch) and in planes in between provided clear evidence that optimum activation can be found in planes that do not coincide with the planes of the semicircular canals but are distributed over all possible spatial planes through the head. 3. Definite evidence of clustering in subdivisions of PIVC of neurons responding to the same optimum rotation plane was obtained in squirrel monkeys and is also suggested to exist in PIVC of Java monkeys. 4. Nearly all neurons responding to vestibular stimulation were also activated by visual large-field movement (optokinetic stimulation). Responses to optokinetic stimuli were always at optimum when the direction of the movement pattern corresponded to the optimum vestibular plane. Two classes of visual-vestibular interaction were found: Synergistic neurons were those PIVC cells with the strongest response to visual movement stimulation in the opposite direction to that leading to a maximum response to vestibular stimulation. Antagonistic neurons had a response maximum when the visual stimulus was moved in the direction of optimum vestibular stimulation. 5. Most PIVC neurons responded to stimulation of the deep mechanoreceptors in the neck region. This input from the neck receptors was tested quantitatively only in the horizontal plane (trunk rotation with the head fixed in space or head rotation with the trunk fixed in space). It interacted with vestibular signals at the PIVC neurons either in an antagonistic or a synergistic manner, the latter meaning activation during rotation of the head in the same direction as that leading to activation induced by semicircular canal stimulation. 6. In addition to the direction-specific vestibular, visual, and neck receptor inputs, a rather complex somatosensory input to PIVC neurons exists, including responses to stimulation of mechanoreceptors of the skin, the muscles, and the joint receptors of legs and arms. Total body vibration also led to activation of some of the neurons.(ABSTRACT TRUNCATED AT 400 WORDS)

P300-mapping--a neurophysiological tool to quantify cerebral dysfunction after coronary artery bypass grafting.

Objective parameters are needed to quantify cerebral dysfunction following cardiac surgery in outcome and comparative studies. In this investigation we assessed the value of the late auditory evoked potentials N100 and P300 to measure the neuropsychological deficit after coronary artery bypass grafting (CABG). N100, an exogenous potential is influenced by the stimulus pattern (frequency, intensity and stimulus presentation rate). P300, an endogenous potential, depends on the cognitive processing invoked by the stimulus. With approval of the Human Investigation Committee and the patients' consents, 52 subjects undergoing elective CABG were enrolled. Operation, extracorporal circulation, anesthesia and postoperative intensive care were standardized. Twenty-channel recordings of N100 and P300 were obtained for off-line analysis. P300 was elicited using an oddball paradigm with rare target tones interspersed among frequent non-target tones. Additionally, neuropsychological tests (syndrome short test SKT and letter cancellation test) were carried out. Neurological examination and all tests were compared preoperatively and one week postoperatively. A significant deterioration in cerebral function was documented by the SKT score (P = 0.04), an increase in P300 latency (P = 0.004) and an increase of mistake rate in counting the P300 target tone (P = 0.02). No differences between preoperative and postoperative testing were found for letter cancellation, P300 amplitude and any N100 parameter. No correlation was found between the preoperative/postoperative changes in SKT score and P300 latency. P300 was proved to be an objective neurophysiological parameter that allows for the quantification of cerebral function after CABG.

Impairment-oriented training or Bobath therapy for severe arm paresis after stroke: a single-blind, multicentre randomized controlled trial.

OBJECTIVE: To study the effects of augmented exercise therapy time for arm rehabilitation as either Bobath therapy or the impairment-oriented training (Arm BASIS training) in stroke patients with arm severe paresis. DESIGN: Single blind, multicentre randomized control trial. SETTING: Three inpatient neurorehabilitation centres. SUBJECTS: Sixty-two anterior circulation ischaemic stroke patients. INTERVENTIONS: Random assignment to three group: (A) no augmented exercise therapy time, (B) augmented exercise therapy time as Bobath therapy and (C) augmented exercise therapy time as Arm BASIS training. MAIN OUTCOME MEASURE: Fugl-Meyer arm motor score. Secondary measure: Action Research Arm Test (ARA). Ancillary measures: Fugl-Meyer arm sensation and joint motion/pain scores and the Ashworth Scale (elbow flexors). RESULTS: An overall effect of augmented exercise therapy time on Fugl-Meyer scores after four weeks was not corroborated (mean and 95% confidence interval (CI) of change scores: no augmented exercise therapy time (n=20) 8.8, 5.2-12.3; augmented exercise therapy time (n=40) 9.9, 6.8-13.9; p = 0.2657). The group who received the augmented exercise therapy time as Arm BASIS training (n=20) had, however, higher gains than the group receiving the augmented exercise therapy time as Bobath therapy (n=20) (mean and 95% CI of change scores: Bobath 7.2, 2.6-11.8; BASIS 12.6, 8.4-16.8; p = 0.0432). Passive joint motion/pain deteriorated less in the group who received BASIS training (mean and 95% CI of change scores: Bobath -3.2, -5.2 to -1.1; BASIS 0.1, -1.8-2.0; p = 0.0090). ARA, Fugl-Meyer arm sensation, and Ashworth Scale scores were not differentially affected. CONCLUSIONS: The augmented exercise therapy time as Arm BASIS training enhanced selective motor control. Type of training was more relevant for recovery of motor control than therapeutic time spent.

Discharge properties of primary auditory fibres in Caiman crocodilus: comparisons and contrasts to the mammalian auditory nerve.

Single fibre recordings were performed from the auditory nerve of the caiman, Caiman crocodilus. All neurones were spontaneously active (1-80 imp/s). Clicks evoked multiple peaks in the post stimulus time histogram spaced at 1/CF. At high intensities irregularities were observed. The latencies of the first peak observable were intensity-dependent and related to CF. The number of peaks was correlated with tuning properties of the fibre. Frequency threshold curves were asymmetrical, with low frequency slopes less steep than high frequency slopes. Q10 dB was between 1.5 and 7 with best tuning at high CF. CF ranged from 30 Hz to 2.8 kHz, lowest thresholds down to 5 dB SPL. Intensity functions were nonmonotonic. In isointensity contours the best frequency shifted downwards with increasing stimulus level. At highest levels a response dip was observed above CF. Phase locking, two tone suppression and excitability by combination tones were observed. In comparison to the mammalian cochlea similarities and differences were found.

[Spinal meningioma as differential diagnosis of diabetic polyneuropathy]. / Spinales Meningeom als Differenzialdiagnose der diabetischen Polyneuropathie.

HISTORY AND ADMISSION FINDINGS: A 70 year old woman had suffered from diabetes mellitus type 2 since she was 52. Three years before the surgery she had begun to experience weakness together with altered sensitivity in the right leg, which was regarded as having been caused by diabetic polyneuropathy. During the admission examination the level for algesia on the right-hand side was at about D 11, a distal paraparesis of the leg (3-4 degrees, Janda's classification), more intense on the right, hyperactive deep tendon reflexes, Babinski's reflex on both sides, and depressed abdominal cutaneous reflexes. The sensitivity to vibrations on the Malleolus medialis on both sides was 0/8. The patient could walk only with the help of a Rollator. INVESTIGATIONS: Over the three-year period following onset of symptoms the following tests were carried out: motor nerve conduction speeds of the N. tibialis and N. peronaeus, electromyogram of the N. tibialis anterior and the M. gastrocnemius, somatosensory evoked potentials (SSEP) of the N. tibialis, which indicated a lesion in the peripheral nerves or nerve roots. Cranial computed tomography (CCT), CT scan of the lumbar spine (L3-S1) and angiological investigation elicited no significant pathological findings. An MRI of the thoracal spine showed a vertebra-sized dorsal tumor pressing on the spinal cord from left to right. TREATMENT AND COURSE: By means of microsurgery the spinal tumor was completely removed. Suspected meningeoma was confirmed by histological analysis. During the post-surgical period, the incomplete paraplegia quickly regressed, and 7 weeks after the removal of the spinal meningeoma the patient was able to climb stairs. CONCLUSION: In case of slowly-developing paresis of the legs in diabetic patients, diabetic polyneuropathy should not be diagnosed without careful consideration, and rare spinal tumors should be considered as part of the differential diagnosis, especially if the blood glucose level is normal, and intensive physiotherapy brings no improvement in the patient's condition.

Role of the parietal cortex for sensorimotor transformation. Evidence from clinical observations.

Somatosensory and motor functions of both hands were examined in 10 patients with unilateral parietal cortex lesions as revealed by computerized tomography. Tests of elementary somatosensory functions comprised surface sensibility, vibration, and position sense. For evaluation of complex somatosensory functions, the recognition of surface textures and object forms was tested. Motor performance was examined by measuring force and position control as well as manipulative and explorative motor behaviour. All patients showed varying degrees of sensory disturbance. Although the patients had no or minor paresis, they all had motor deficits concerning force control, fine movements, and manipulation with the hand contralateral to the lesion. Patients with more posteriorly located parietal lesions revealed predominantly severe disturbances of complex sensibility, precision grip, manipulation, and explorative finger movements. The characteristic and consistent feature of the disturbed motor behaviour was the loss of the purposive nature of the motor acts which were no longer adequate for the tasks (tactile apraxia). Paresis or ataxia could not account for this deficits.

Early cerebral functional outcome after coronary artery bypass surgery using different acid-base management during hypothermic cardiopulmonary bypass.

BACKGROUND: Cerebral injury can render meaningless an otherwise successful cardiac operation. As carbon dioxide management during hypothermic cardiopulmonary bypass has a major impact on cerebral blood flow during bypass, it may also influence postoperative cerebral function. The objective of this prospective, controlled, double-blind study was to compare the effect of pH-stat (temperature correction of blood gas analyses) or alpha-stat (no temperature correction) on brain function. METHODS: Cerebral function was assessed non-invasively using neurological examination, a neuropsychological test battery, quantitative electroencephalogram and the cognitive evoked potential P300 preoperatively and on postoperative day 7 or 8. Forty-five patients undergoing elective aortocoronary bypass grafting in barbiturate/opiate anesthesia were randomised into a pH-stat-(n = 23) and an alpha-stat-group (n = 22). Membrane oxygenators with arterial line filtration and non-pulsatile flow at a perfussion pressure of 50-60 mmHg were used throughout. RESULTS: One patient in each group developed a new paresis. Among 49 comparisons of cerebral function parameters, only 3 showed significant differences at the 5%-level, i.e. exactly what is expected purely by chance. These differences were too small to be clinically relevant and favored either pH-stat (theta-amplitude) or alpha-stat (subtest 3 of syndrome-short-test, number of mistakes in aiming). CONCLUSION: Under the bypass conditions of this study there was no difference in early cerebral functional outcome between pH-or alpha-stat carbon dioxide management during hypothermic cardiopulmonary bypass.

Three methods to elicit sigma-optokinetic nystagmus in Java monkeys.

Sigma-optokinetic nystagmus (sigma-OKN) can be elicited in awake Java monkeys (Macaca fascicularis) when stationary periodic visual patterns (grid of black white stripes, row of equally spaced dots) are illuminated stroboscopically. Three methods were found to be useful in inducing the sigma-OKN: postrotatory nystagmus, optokinetic afternystagmus (OKAN) following normal OKN and a gradual transition from phi-movement (phi-OKN) to sigma-OKN. The properties found for sigma-OKN in man are also present in monkeys with the one exception that monkeys have a long-lasting sigma-OKAN in darkness which is not present in man. The average angular speed Ve of sigma-OKN slow phases was related to the flash frequency fs and the spatial period Ps of the stripe pattern according to the following equation: Ve = k.Ps . fs [degrees . s-1] The constant k was 1 or close to 1.

Sensorimotor disturbances in patients with lesions of the parietal cortex.

Somatosensory and motor disturbances of hand function were examined in 9 patients with parietal lobe lesions. A quantitative score was used for the elaboration of sensorimotor profiles displaying the relative degree of functional impairment. In patients with anterior parietal lobe lesions somaesthesis was clearly more disturbed than motor function. Simple aspects of somaesthesis (surface sensibility, two-point discrimination, position sense) were disturbed to about the same degree as complex somatosensory (tactile recognition) tasks. On the other hand, patients with lesions of the posterior parietal lobe showed preferential impairment of complex somatosensory and motor functions (exploratory and manipulative finger movements). In 4 patients, analysis of motor behaviour by means of an optoelectronic system showed that reaching, formation of hand aperture and target acquisition were less disturbed than manipulative behaviour. Finger movement trajectories during dynamic digital palpation of objects were grossly deranged in the patients with posterior parietal damage. The temporal characteristics of the finger movements during active touch were completely destroyed. This leads to a breakdown of the finely tuned digital scanning process required for the sequential sampling of mechanoreceptive information. Remarkably, these patients could produce the exploratory finger movements imitatively. The motor disability of the parietal hand does not lie in the loss of the kinetic memory to perform these movements, but in the loss of their evocation by appropriate sensory stimuli. This deficit is not due to a lack of somatosensory information because that may be relatively well preserved. It is concluded that the motor disturbance in posterior parietal lobe disease lies essentially in the conception and execution of the spatiotemporal movement patterns necessary to bring those receptors into action which would normally provide the information about tactile objects. This illustrates the intricate mutual dependence of the spatiotemporal organization of receptor activation by movement and of the formation of movement trajectories on the basis of adequate sensory processing.

Localization and responses of neurones in the parieto-insular vestibular cortex of awake monkeys (Macaca fascicularis).

1. In four Java monkeys (Macaca fascicularis) 152 vestibular neurones were recorded in the parietal cortex located in the upper bank of the lateral sulcus near the posterior end of the insula. We called this region parieto-insular vestibular cortex (PIVC). PIVC extends about 6-8 mm in the anterior-posterior direction from the posterior part of the insula into the retroinsular region (stereotaxic co-ordinates: anterior 4-12 mm, lateral 16-19 mm and vertical 3-6 mm). 2. About two-thirds of the neurones recorded from this region responded to vestibular stimuli; the non-vestibular neurones responded predominantly to somatosensory stimulation of the neck and shoulder region. The PIVC area is a polysensory field, since almost all vestibular neurones were also activated by somatosensory and visual stimuli. Large-field optokinetic stimulation was the most effective visual stimulus. 3. With vestibular stimuli, responses to angular acceleration were dominant; steady tilt in darkness rarely led to any change in neuronal spontaneous activity. Of sixty-four neurones tested by rotation in more than one plane, fifty-four responded to excitation of semicircular canal receptors aroused by rotation in more than one of the three experimental planes (roll, yaw, pitch). Compared with vestibular brain stem units PIVC neurones discharged with a higher variability. 4. In the responses to horizontal rotation of the animal 38% type I, 53% type II and 9% type III units were recorded (classification according to Duensing & Schaefer, 1958). The gain measured with horizontal sinewave rotation was lower by a factor of about 4 in PIVC neurones as compared with the responses of vestibular neurones in the brain stem or thalamus (VPL). The phase response characteristics and the gain increase with increasing sinewave stimulus frequency, however, were in the same range as observed in neurones of the afferent vestibular system. 5. When the vestibular responses to sinusoidal rotation were tested in all three experimental planes (yaw, roll, pitch), the response strength as expressed by the amplitude of the peristimulus time histograms (PSTHs) differed for the three rotational planes. For different units the relative sensitivity to rotation in each of the three planes also differed. We concluded from this observation that different PIVC units had different optimum sensitivity planes for rotation with respect to the head co-ordinates, whereby all possible planes are represented.

Vestibular neurones in the parieto-insular cortex of monkeys (Macaca fascicularis): visual and neck receptor responses.

1. One hundred and fifty-two vestibularly activated neurones were recorded in the parieto-insular vestibular cortex (PIVC) of four awake Java monkeys (Macaca fascicularis): sixty-two were tested systematically with visual stimulation and seventy-nine were tested with various somatosensory stimuli. With very few exceptions all vestibular neurones tested responded to visual and somatosensory stimulation, therefore being classified as polymodal vestibular units. 2. A most effective stimulus for all fifty-eight visually activated PIVC units was movement of a large structured visual pattern in an optimal direction. From forty-four units responsive to a horizontally moving optokinetic striped drum, twenty-nine were activated with optokinetic movement in the opposite direction to the activating vestibular stimulus ('synergistic' response), thirteen were activated optokinetically and vestibularly in the same direction ('antagonistic' responses) and two were biphasic. The gain of the optokinetic response to sinusoidal stimulation (average 0.28 (impulses s-1) (deg s-1)-1 at 0.2 Hz, 56 deg amplitude) was in a range similar to that of the vestibular gain at low frequencies. At 1 Hz some units only showed weak optokinetic responses or none at all, but the vestibular response was still strong. 3. With different 'conflicting' or 'enhancing' combinations of optokinetic and vestibular stimulation no generalized type of interaction was observed, but the responses varied from nearly 'algebraic' summation to no discernible changes in the vestibular responses by additional optokinetic stimuli. With all visual-vestibular stimulus combinations the responses to the vestibular stimulus remained dominant. 4. The optokinetic preferred direction was not related to gravitational coordinates since the optokinetic responses were related to the head co-ordinates and remained constant with respect to the head co-ordinates at different angles of steady tilt. 5. Almost all PIVC units were activated by somatosensory stimulation, whereby mainly pressure and/or movement of neck and shoulders (bilateral) and movement of the arm joints elicited vigorous responses. Fewer neurones were activated by lightly touching shoulders/arms or neck, by vibration and/or pressure to the vertebrae, pelvis and legs. 6. A most effective somatosensory stimulus was sinewave rotation of the body with head stationary. The gain of this directionally selective neck receptor response was in the range of vestibular stimulation. Interaction of vestibular and neck receptor stimulation was either of a cancellation or facilitation type.(ABSTRACT TRUNCATED AT 400 WORDS)