Citations
Complex regional pain syndrome (CRPS) type I in stroke patients is usually known to affect the hemiplegic upper limb. We report a case of CRPS presented in an ipsilesional arm of a 72-year-old female patient after an ischemic stroke at the left middle cerebral artery territory. Clinical signs such as painful range of motion and hyperalgesia of her left upper extremity, swollen left hand, and dystonic posture were suggestive of CRPS. A three-phase bone scintigraphy showed increased uptake in all phases in the ipsilesional arm. Diffusion tensor tractography showed significantly decreased fiber numbers of the corticospinal tract and the spinothalamic tract in both unaffected and affected hemispheres. Pain and range of motion of the left arm of the patient improved after oral steroids with a starting dose of 50 mg/day.
Citations
The authors report the diffusion tensor tractography (DTT) findings of three pediatric patients with gait dysfunction and corticoreticular tract (CRT) disruption. All three patients showed unilateral trunk instability, but they did not show any spasticity or weakness of the distal extremities. Clinical evaluation of trunk instability using a Trunk Control Measurement Scale (TCMS) revealed that the more affected side had a lower score than the contralateral side. DTT showed disrupted CRTs in hemispheres contralateral to the hemiparetic sides, which were associated with unilateral proximal instability, although conventional MRI showed no abnormal lesion explaining the hemiplegic symptom. Compared to the results in age-matched controls, these three patients had decreased values of fractional anisotropy (FA) and tract volumes (TV) of the affected CRTs, and these values were also decreased compared to those in the contralateral side. On the other hand, values of FA and TV of the corticospinal tracts on the ipsilateral and contralateral sides were only marginally different. In conclusion, diffusion tensor imaging can be helpful for investigating the state of the CRT in pediatric patients with trunk instability and gait dysfunction.
Citations
Cerebellar mutism (CM) is a rare neurological condition characterized by lack of speech due to cerebellar lesions. CM is often reported in children. We describe a rare case of CM after spontaneous cerebellar hemorrhage. The patient showed mutism, irritability, decreased spontaneous movements and oropharyngeal apraxia. Diffusion tensor imaging revealed significant volume reduction of medial frontal projection fibers from the corpus callosum. In Tracts Constrained by UnderLying Anatomy (TRACULA) analysis, forceps major and minor and bilateral cingulum-angular bundles were not visualized. Cerebello-frontal pathway reconstructed from the FMRIB Software Library showed continuity of fibers, with decreased number of fibers on qualitative analysis. These results suggest that cerebello-frontal disconnection may be a neuroanatomical mechanism of CM. Damage of brain network between occipital lobe, cingulate and cerebellum caused by hemorrhage may also have role in the mechanism of CM in our case.
Citations
We present the case of a 33-year-old man who experienced a 10,000-V electrical shock when working with electrical wiring. He suffered third-degree burns on his scalp at the right occiput (entry wound) and on his left arm (exit would), and a second-degree burn on his left foot (exit wound). He presented with severe spasticity of both lower extremities, motor weakness with a Medical Research Council grade of 3, and sensory impairments below thoracic level 11 that included an inability to sense light touch and defects in proprioception. Initial magnetic resonance imaging (MRI) scans of his spine and brain showed no definite abnormalities. However, tractography obtained by diffusion tensor imaging of the brain showed absence of the right medial lemniscus tract. A cervical MRI scan 1 month later showed spinal cord swelling from cervical 1-5 levels, and signal changes in the lateral and posterior white matter in the axial view. After 6 months of rehabilitation, he recovered almost normal degree of motor function in his lower extremities and disappearance of spasticity. However, since the sensory impairments persisted, especially defects in proprioception, he was unable to walk independently.
Citations
A 51-year-old man showed hemiplegia on his right side after a traumatic brain injury (TBI). On initial brain computed tomography (CT) scan, an acute subdural hemorrhage in the right cerebral convexity and severe degrees of midline shifting and subfalcine herniation to the left side were evident. On follow-up brain magnetic resonance imaging (MRI), there were multiple microhemorrhages in the left parietal and occipital subcortical regions. To explain the occurrence of right hemiplegia after brain damage which dominantly on the right side of brain, we used diffusion tensor imaging (DTI) to reconstruct the corticospinal tract (CST), which showed nearly complete injury on the left CST. We also performed motor-evoked potentials, and stimulation of left motor cortex evoked no response on both sides of upper extremity. We report a case of patient with hemiplegia after TBI and elucidation of the case by DTI rather than CT and MRI.
Citations
To determine the supratentorial area associated with poststroke dysphagia, we assessed the diffusion tensor images (DTI) in subacute stroke patients with supratentorial lesions.
We included 31 patients with a first episode of infarction in the middle cerebral artery territory. Each subject underwent brain DTI as well as a videofluoroscopic swallowing study (VFSS) and patients divided were into the dysphagia and non-dysphagia groups. Clinical dysphagia scale (CDS) scores were compared between the two groups. The corticospinal tract volume (TV), fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were calculated for 11 regions of interest in the supratentorial area—primary motor cortex, primary somatosensory cortex, supplementary motor cortex, anterior cingulate cortex, orbitofrontal cortex, parieto-occipital cortex, insular cortex, posterior limb of the internal capsule, thalamus, and basal ganglia (putamen and caudate nucleus). DTI parameters were compared between the two groups.
Among the 31 subjects, 17 were diagnosed with dysphagia by VFSS. Mean TVs were similar across the two groups. Significant inter-group differences were observed in two DTI values: the FA value in the contra-lesional primary motor cortex and the ADC value in the bilateral posterior limbs of the internal capsule (all p<0.05).
The FA value in the primary motor cortex on the contra-lesional side and the ADC value in the bilateral PLIC can be associated with dysphagia in middle cerebral artery stroke.
Citations
A 50-year-old man with liver cirrhosis and esophageal varix for 3 years was diagnosed with hematemesis and treated for a bleeding varix. However, bleeding recurred 11 days later, and he developed drowsiness with left hemiparesis. His left upper and lower extremity muscle strengths based on the manual muscle test at the onset were grade 2/5 and 1/5, respectively. The Babinski sign was positive. His serum ammonia level was elevated to 129.9 µg/dL (normal, 20-80 µg/dL). Magnetic resonance imaging revealed restriction on diffusion and T2-hyperintensities with decreased apparent diffusion coefficient values in the bilateral frontoparietooccipital cortex. The effect was more severe in the right hemisphere and right parietooccipital cortices, which were compatible with hepatic encephalopathy. Although the patient's mental status recovered, significant left-sided weakness and sensory deficit persisted even after 6 months. Diffusion tensor tractography (DTT) performed 3 months post-onset showed decreased volume of the right corticospinal tract. We reported a patient with hepatic encephalopathy involving the corticospinal tract by DTT.
Citations
We report the findings of 18F-fluorodeoxyglocese positron emission tomography (FDG-PET) and diffusion tensor tractography (DTT) in a right-handed patient presenting with callosal disconnection syndrome, including alien hand syndrome, after an anterior communicating artery aneurysmal rupture. The 49-year-old patient had right hemiparesis and unintended movement of the right hand during action of the left hand. A brain magnetic resonance imaging revealed lesions in the upper part of the genu and body in the corpus callosum as well as hemorrhage in the inter-hemispheric fissure. We observed extensive disruption of corpus callosum fibers in the upper genu and trunk by DTT for the evaluation of inter-hemispheric connection. FDG-PET revealed severe hypometabolism in the left cerebral hemisphere, including basal ganglia and thalamus, and hypermetabolism in the right cerebral hemisphere. Based on findings of FDG-PET and DTT, the callosal disconnection syndrome presented in the patient could be the result of loss of transcallosal inhibition in the contralateral hemisphere.
Citations
To investigate neuroradiological and neurophysiological characteristics of patients with dyskinetic cerebral palsy (CP), by using magnetic resonance imaging (MRI), voxel-based morphometry (VBM), diffusion tensor tractography (DTT), and motor evoked potential (MEP).
Twenty-three patients with dyskinetic CP (13 males, 10 females; mean age 34 years, range 16-50 years) were participated in this study. Functional evaluation was assessed by the Gross Motor Functional Classification System (GMFCS) and Barry-Albright Dystonia Scale (BADS). Brain imaging was performed on 3.0 Tesla MRI, and volume change of the grey matter was assessed using VBM. The corticospinal tract (CST) and superior longitudinal fasciculus (SLF) were analyzed by DTT. MEPs were recorded in the first dorsal interossei, the biceps brachii and the deltoid muscles.
Mean BADS was 16.4±5.0 in ambulatory group (GMFCS levels I, II, and III; n=11) and 21.3±3.9 in non-ambulatory group (GMFCS levels IV and V; n=12). Twelve patients showed normal MRI findings, and eleven patients showed abnormal MRI findings (grade I, n=5; grade II, n=2; grade III, n=4). About half of patients with dyskinetic CP showed putamen and thalamus lesions on MRI. Mean BADS was 20.3±5.7 in normal MRI group and 17.5±4.0 in abnormal MRI group. VBM showed reduced volume of the hippocampus and parahippocampal gyrus. In DTT, no abnormality was observed in CST, but not in SLF. In MEPs, most patients showed normal central motor conduction time.
These results support that extrapyramidal tract, related with basal ganglia circuitry, may be responsible for the pathophysiology of dyskinetic CP rather than CST abnormality.
Citations
To investigate the factors which affect the motor evoked potential (MEP) responsiveness and parameters and to find the correlation between the function of the upper extremities and the combined study of MEP with a diffusion tensor tractography (DTT) in patients with stroke.
A retrospective study design was used by analyzing medical records and neuroimaging data of 70 stroke patients who underwent a MEP test between June 2011 and March 2013. MEP parameters which were recorded from the abductor pollicis brevis muscle were the resting motor threshold, latency, amplitude, and their ratios. Functional variables, Brunnstrom stage of hand, upper extremity subscore of Fugl-Meyer assessment, Manual Function Test, and the Korean version of Modified Barthel Index (K-MBI) were collected together with the biographical and neurological data. The DTT parameters were fiber number, fractional anisotropy value and their ratios of affected corticospinal tract. The data were compared between two groups, built up according to the presence (MEP-P) or absence (MEP-N) of MEP on the affected hand.
Functional and DTT variables were significantly different between MEP-P and MEP-N groups (p<0.001). Among the MEP-P group, the amplitude ratio (unaffected/affected) was significantly correlated with the Brunnstrom stage of hand (r=-0.427, p=0.013), K-MBI (r=-0.380, p=0.029) and the time post-onset (r=-0.401, p=0.021). The functional scores were significantly better when both MEP response and DTT were present and decreased if one or both of the two studies were absent.
This study indicates MEP responsiveness and amplitude ratio are significantly associated with the upper extremity function and the activities of daily living performance, and the combined study of MEP and DTT provides useful information.
Citations
Central pontine myelinolysis is a rare neurologic disorder that is defined by demyelination of longitudinally descending tracts and transversly crossing fibers in the basis pontis. Frequently observed clinical manifestations of this disorder include sudden weakness, dysphagia, loss of consciouness and locked-in syndrome. However, there have been a few studies that reported a benign course of this disease, which include cerebellar signs, such as ataxia, intention tremor, and dysarthria. Here we report on a 53-year-old male with a history of liver cirrhosis who showed the cerebellar type of central pontine myelinolysis. The patient was diagnosed with central pontine myelinolysis based on clinical presentations and magnetic resonance imaging findings after a liver transplantation. Conventional magenetic resonance imaging (MRI) revealed the preservation of the corticospinal tract and abnormal pontocerebellar fibers. However, these findings were not sufficient to define the pathophysiology of our patient. Electrophysiologic analysis and diffusion tensor imaging (DTI) were performed to investigate cerebellar signs in this case. Delayed central motor conduction time (CMCT) to the tibialis anterior muscle with transcranial magnetic stimulation (TMS) was observed, which indicated demyelination of the corticospinal tract. Also, diffusion tensor imaging showed abnormal pontocerebellar fibers, which might have been caused by cerebellar dysfunction in our patient. A combination of TMS and DTI was also used to determine the pathophysiology of this disease.
Citations
Method: Thirty-six post-stroke hemiplegic patients with a lesion in the internal capsule were included in this study. Diffusion tensor imaging (DTI) was performed with a 3.0 tesla MR at about 1 month after stroke. FA ratio was measured in posterior limb of the internal capsule of the patients. Motor evoked potential (MEP) was obtained by magnetic stimulation of the motor cortex and recorded from the abductor pollicis muscle. Somatosensory evoked potential (SSEP) was obtained by electrical stimulation of the median nerve at the wrist and recorded from the somatosensory cortex. Hand movement scale was obtained at about 1 month and 3 months after stroke. Results: Hand movement scale at about 1 month and 3 months after stroke and FA ratio were reduced significantly in patients who showed no response on MEP. However, no significant differences were observed between the patients who showed SSEP response and those who did not. FA ratio and hand movement scale were highly correlated to each other. Conclusion: MEP and FA ratio can be helpful in assessing the hand function at about 1 month and 3 months in post-stroke hemiplegic patients. (J Korean Acad Rehab Med 2008; 32: 182-188)
First
Prev
