Portable Multi Channel EEG Signal Acquisition System / 中国医疗器械杂志

This study introduces a portable multi-channel EEG signal acquisition system. The system is mainly composed of EEG electrode connector, signal conditioning circuit, EEG acquisition part, main control MCU and power supply part. The low-power EEG acquisition front-end ADS1299 and STM32 are used to form the signal acquisition and data communication part. The collected EEG signal can be transmitted to the PC for real-time display. After relevant tests, the system has small volume, low power consumption, high signal-to-noise ratio, and meets the requirements of portable wearable medical devices.

Quantitative analysis of MRI of partial acute tear of anterior cruciate ligament / 中华创伤骨科杂志

Objective To investigate the range of gray values of MRI local hyperintensity signals corresponding to the classification of partial tear of knee anterior cruciate ligament (ACL) under arthroscopy so as to evaluate its significance for diagnosis and treatment of acute partial ACL tear.Methods A retrospective analysis was conducted of 82 patients who had identical orthopaedic and MRI findings at Department of Orthopaedics and Traumatology,Shenzhen Baoan People's Hospital from January 2014 to June 2016.They were 49 males and 33 females;their ages ranged from 18 to 71 years,with an average of 39.6 years;27 left and 55 right knees were involved.Of them,67 were assigned into an ACL tear group in which both arthroscopic and MRI findings indicated diagnosis of acute ACL partial tear,and 15 into an ACL normal group in which both arthroscopic and MRI findings indicated diagnosis of normal ACL but injury to meniscus and/or articular cartilage.According to the arthroscopic grading,the 67 patients were rated as grade Ⅰ in 21 cases,as grade Ⅱ in 19,and as grade Ⅲ in 27.Software Photoshop CS4.0 was used to measure the gray values of local hyperintensity signals of the partial ACL tear in the MRI in the ACL tear group and the overall gray values of local hyperintensity signals of the normal ACL in MRI in the ACL normal group.The 2 groups were compared in terms of the range of gray values of MRI local hyperintensity signals and the proportion of ACL partial tear under arthroscopy.Results The range of gray values of MRI local hyperintensity signals in diagnosis of acute ACL partial tear was 20.24 ± 7.77 for the ACL normal group,67.54 ± 8.78 for the grade Ⅰ ACL partial tear,90.99 ± 7.21 for the grade Ⅱ tear,and 138.89 ± 32.40 for the grade Ⅲ tear,showing significant differences between the 4 groups and any 2 of the 4 groups as well (both P ＜ 0.05).The percentage of ACL partial tear under arthroscopy was 0 for the ACL normal group,0.22 ± 0.08 for the grade Ⅰ ACL partial tear,0.56 ± 0.08 for the grade Ⅱ tear,and 0.84 ± 0.064 for the grade Ⅲ tear,showing significant differences between the 4 groups and any 2 of the 4 groups as well (both P ＜ 0.05).Twenty-six patients (21 cases of grade Ⅰ and 5 ones of grade Ⅱ tear) received symptomatic treatment of the injury to the meniscus and/or articular cartilage without ACL reconstruction due to good function of residual ACL and stable knee joint.Forty-one patients (14 cases of grade Ⅱ and 27 ones of grade Ⅲ tear) underwent ACL reconstruction and treatment of co-morbidities because of poor function of residual ACL and instability of the knee joint.Conclusion The range of gray values of MRI local hyperintensity signals can be used to assist diagnosis and classification of acute ACL partial tear.

Significance of Intramedullary High Signal Intensity on Magnetic Resonance Imaging in Patients with Cervical Ossification of the Posterior Longitudinal Ligament

BACKGROUND: The purpose of this study was to analyze the relation between intramedullary high signal intensity (IMHS) on magnetic resonance imaging (MRI), radiographic parameters, and clinical symptoms in cervical ossification of the posterior longitudinal ligament (OPLL) patients. METHODS: Two hundred forty-one patients, who underwent simple radiography, computed tomography (CT), and MRI were included in the present study. As radiographic parameters, the OPLL occupying ratio and occupying area were measured on CT images. Dynamic factors were assessed by measuring cervical range of motion (ROM) on simple radiographs. Visual analog scale (VAS) for neck and arm pain, and Japanese Orthopaedic Association (JOA) scores were evaluated for clinical analysis. The differences in radiographic and clinical findings were assessed between patients with IMHS on T2-weighted MRI findings (group A) and patients without IMHS (group B). RESULTS: Eighty-one patients were assigned to group A and 160 patients to group B. The occupying ratios were found to be higher in group A than in group B on both sagittal and axial views (p < 0.01). Group A also showed a higher area occupying ratio (p < 0.01). The length and area of underlying spinal canal on the sagittal and cross-sectional planes were lower in group A than in group B (p < 0.01). No significant difference in ROM was observed (p = 0.63). On the clinical findings, group A had a lower JOA score (p < 0.001), and no intergroup differences in VAS scores were observed. CONCLUSIONS: In cervical OPLL cases, IMHS on MRI was associated with manifestation of myelopathic symptom. Occupying ratio was associated with high signal intensity on MRI, whereas no association was found with ROM. Occurrence of high signal intensity increased inversely with the length and area of underlying spinal canal.

Liver transplantion in a patient with rapid onset parkinsonism-dementia complex induced by manganism secondary to liver failure

Bilateral and symmetric globus-pallidus hyperintensities are observed on T1-weighted MRI in most of the patients with chronic liver failure, due to manganese accumulation. We report a 53-year-old man, with rapid onset parkinsonism-dementia complex associated with accumulation of manganese in the brain, secondary to liver failure. A brain MRI was performed and a high signal on T1-weighted images was seen on globus-pallidus, as well as on T2-weighted images on the hemispheric white-matter. He was referred to a liver-transplantation. The patient passed away on the seventh postoperative day. Our findings support the concept of the toxic effects of manganese on the globus-pallidus. The treatment of this form of parkinsonism is controversial and liver-transplantation should not be considered as first line treatment but as an alternative one.

Hiperintesidades simétricas e bilaterais dos gânglios da base são observadas em imagens de ressonância magnética encefálica (RM) ponderadas em T1 na maioria dos pacientes com insuficiência hepática crônica devidas ao acúmulo de manganês. Nós relatamos o caso de um homem, com 53 anos de idade, com um complexo parkinsonismo-demência rapidamente progressivo associado com o acúmulo de manganês no cérebro, secundariamente a insuficiência hepática. Uma RM encefálica foi realizada e foram observadas imagens hiperintensas/hipersinal nas imagens ponderadas em T1 no globo pálido e, também, na substância branca dos hemisférios cerebrais ponderadas em T2. Devido à falta de resposta ao tratamento clinico optamos pelo transplante hepático. O paciente faleceu no 7° dia de PO. Nossos achados corroboram o conceito dos efeitos tóxicos do manganês nos gânglios da base/globo pálido. O tratamento desta forma de parkinsonismo é controverso e o transplante hepático não deverá ser considerada uma opção terapêutica de primeira linha, porém como um tratamento alternativo considerando-se os riscos-benefícios dessa escolha.

Two Cases of Cerebral Venous Thrombosis with High Signal Intensity of Intravascular Clots on Diffusion Weighted Image

High signal intensity on diffusion-weighted image (DWI) at the site of venous occlusion has previously been reported in cerebral venous thrombosis (CVT). The frequency and diagnostic value of these signal changes in CVT were unknown. Some authors suggest that the presence of high signal intensity on DWI in occluded veins might help diagnose CVT and suggest low rate of recanalization. We experienced two cases of CVT with high signal intensity at the site of intravascular clot on DWI.

Surgical treatment of cervical ossification of posterior longitudinal ligament with high-signal intensity zone and analysis of the curative effect / 中国矫形外科杂志

[Objective]To observe and analyze the clinical results of ossification of posterior longitudinal ligament(OPLL) combined with high-signal intensity zone(HIZ) change. [Methods]Forty patients with OPLL combined with HIZ were treated from March 2004 to March 2008.Anterior approach surgery was given to 19 cases as group A and posterior approach surgery was given to 21 cases as group P.All cases were followed up.The pre-and post-operative JOA17 scores and improvement ratio were evaluated.[Results]The mean follow-up time were(19.5?3.4) months in group A and(20.3?4.5) months in group P.The mean improvement ratio were(56.2?8.4)% in group A and(52.2?12.2)% in group P.There were no statistical differences between those of groups A and P.Mean JOA scores at last follow-up were(12.8?0.9) in group A and(11.5?1.6) in group P,with significantly difference.[Conclusion]Treatment of OPLL combined with HIZ is a high risk procedure with limited recovery in neoro-function.Good surgical result could be got with correct judgement of type and location of OPLL,occupation ratio of spinal canal and selection of approach.

Cavernous Hemangioma in the Middle Cranial Fossa & Cavernous Sinus

Extracerebral cavernous hemangiomas are rare vascular tumors that are very difficult to remove because of severe intraoperative bleeding. We report a case of 57-year-old male with extracerebral cavernous hemangioma with review of 126 cases in the literature. Patient presented with blurred vision, diplopia, numbness on the left side of his face. Magnetic resonance imaging revealed a well defined mass of 3 x 4 x 3 cm size with heterogenous iso-or hypointensity on T1-weighted image showing strong homogenous contrast enhancement and marked hyperintensity on T2-weighted image. Digital subtraction angiography(DSA) revealed a faint tumor blush by feeders from the left internal carotid artery(ICA) and left external carotid artery(ECA) in the delayed phase. Even with profuse intratumoral bleeding, near total removal was achieved. In addition to preoperative neurologic deficits such as ophthalmoplegia, facial numbness in the V1-2 dermatomes, ptosis appeared postoperatively.

An Association between Brain MRI and Neurologic Findings in Welders Exposed to Manganese Fume / 대한산업의학회지

This study was carried out to investigate the relationship between brain magnetic resonance imaging (MRI) and neurological findings in welders exposed to manganese fume. Thirty five welders from a bus manufacturing factory who were occupationally exposed to low dose manganese fume were examined. We collected the information on the demo graphic factors and welding careers. Laboratory investigations included blood and urine manganese concentration and blood chemistry. Brain MRI was checked, and high signal intensity of the globus pallidus was graded from 0 to 3 compared to the white matter of the frontal lobe. Neurologic examination wart carried out. The results were as follows ; 1. The mean age of workers was 48.3+/-5.7 years, mean duration of welding was 21.4 +/-5.6 Years. 2. On brain MRI, high signal intensity in the globes pallidus was observed in 27 workers (77.1%) Among them, 18 cases (66.7%) showed remarkably high signal intensity (grade 2) Mean concentration of blood manganese was higher in those with high signal intensity and correlated to the grade of high signal intensity (p=0.02) 3. On neurologic examination, no workers showed the finding of typical parkinsonism. But 11 workers (31.4%) showed subtle neurological abnormalities such as gait without associated arm movement, postural instability, intention tremor, and so on. Blood manganese concentration of neurologically abnormal group was 2.4+/-0.7 microgram/dL, which was significantly higher, compared to 1.8+/-0.7 microgram/dL of neurologically normal group (p=0.03). 4. Among 27 workers who showed high signal intensity on brain MRI, 10 workers (37%) were neurologically abnormal. Higher grade of signal intensity on globus pallidus showed higher rate of neurologic abnormality (p<0.05) Especially postural instability and gait without associated arm movement were prominent findings. These bindings suggest that high signal intensity on brain MRI might be associated with a prodromal sign of manganese intoxication. Careful neurologic examination should be tool lowed up on welders showing high signal intensity in the golbus pallidus of brain MRI.

Three Cases of High Signal Intensity by Brain Magnetic Resonance Imaging in CO2 arc Welders / 대한산업의학회지

We experienced three cases of high signal intensity observed by Brain Magnetic Resonance Imaging in CO2 arc welders of steel-frame manufacturing industry. Case 1 was a 35 years old man who has been an CO2 arc welder for 10 years, admitted a sudden onset of tonic clonic seizure. He complained fever, chilling and myalgia since 3 days before admission. On admission, in the test of manganese exposure indices, manganese concentrations of blood, urine and scalp hair were 5.17 microgram/dL, 22.00 microgram/l and 31.25 ppm respectively. Case 2 was a 35 years old man who has been an CO2 arc welder for 20 years. On admission, He complained fatigue, numbness and weakness of extremities, and decrease of libido. In the test of manganese exposure indices, manganese concentrations of blood, urine and scalp hair were 6.34 microgram/dL, 14.62 microgram/l and 57.87 ppm respectively. In neurologic examination, Palmo-mentis reflex and Myerson sign were observed. Case 3 was a 33 years old man who has been an CO2 arc welder for 16 years. On admission, He complainer loss of appetite, numbness of extremities, fatigue and decrease of attention. In the test of manganese exposure indices, manganese concentrations of blood, urine and scalp hair were 5.14 microgram/dL, 13.79 microgram/l and 50.08 ppm respectively. In neurologic examination, Myerson sign was observed. In brain magnetic resonance imaging, T1WI showed symmetrical high signal intensity in basal ganglia and midbrain of three cases. Authors argued that they were developed by manganese exposure, and we considered that follow up study would be necessary.

A study on manganese health hazards among experienced welders / 예방의학회지

This study was conducted to evaluate the health hazards and to develop early diagnostic methods of the manganism in experienced welders and to know the meaning of signal intensities on the brain Magnetic Resonance images. It was carried out from December 1996 to February 1997 with 277 male welders, the duration of welding was at least 5 years or more. The study was consisted of a questionnaire, physical examination and measurements of blood and urine manganese concentrations. Brain Magnetic Resonance imaging was done on 19 study subjects by random sampling. As the duration of welding increases, the positive rates of clinical symptoms, neurological examinations and blood manganese concentrations were also increased. However, physical examinations and urine manganese concentrations were not statistically significant with the duration of welding. Authors couldn't observe any Parkinsonism-like diseases. There were statistically significant correlations between duration of welding and blood manganese concentrations(r=0.16, p<0.01). There were not statistically significant correlations between duration of welding and urine manganese concentrations(r=0.06). There were statistically significant correlations between blood and urine manganese concentrations(r=0.34, p<0.01). By viewing brain Magnetic Resonance images, 13 welders(68.4 %) among 19 welders were found to have signal intensities. The positive rates of clinical symptoms, physical examinations, neurological examinations and blood and urine manganese concentrations were not statistically different between those with signal intensities and those without signal intensities. We would like to suggest that some non-specific clinical symptoms and neurological signs are correlated with the duration of welding but any Parkinsonism-like diseases had not been observed with these welders. Next we suggest that the high signal intensities on T1WI of brain Magnetic Resonance images are not the sign of manganese intoxication but the sign of manganese deposition.

Magnetic Resonance Lmaging and Surgical Decision of the Degenerative Cervical Spine Lesions

We undertook a retrospective analysis of 30 patients admitted to the Department of Neurosurgery Dongsan Medical Center Keimyung University utilizing Magnetic Resonanace Imaging(MRI) to make diagnosis and surgical indication of degenerative cervical spine lesions. All patients were taken T1 Weighted Image(T1W1) T2 Weighted Image(T2WI) and gradient echo image on 2.0 Tesla unit. Pre- and postoperative MRI were obtained seven of 15 cases with myelopathy. All patients could be evaluated the extent and degree of disc herniation, osteophytes and cord compression. A focal area of High-Signal-Intensity(HIS) was observed on T2WI in 15 patients with mydlopathy predominantly. HIS diminished postoperatively in the patients who improved clinically and remained the same in one case whose condition remained unchanged after decompression. We think MRI with high resolution images in the initial procedure of choice in decision-making of patients with degenerative cervical spine lesion. Furthermore HIS of the spinal cord produced by compressive lesions appears to be an important indicator for predicting prognosis of patients with myelopathy.

Magnetic Resonance Imaging(MRI) and Surgical Decision of Traumatic and Degenerative Cervical Spine Lesions

We undertook a retrospective analysis of 20 patients admitted to the Department of Neurosurgery, Dongsan Medical Center, Keimyung University, utilizing Magnetic Resonance Imaging(MRI) to make diagnosis and surgical indication of traumatic and degenerative cervical spine lesions. All patients were taken T1 Weighted Lmage(T1WI), T2 Weighted Image(T2WI) and Gradient echo on 2.0 Telsa unit. Pre-and postoperative were obtained in 4 cases with degenerative lesion. All patients could be evaluated the extent and degree of soft tissue injury including intramedullary contusion or hemorrhage, acute or chronic disc herniation, osteophytes, cord compression, epidural/paravertebral hematoma, ligamentous avulsion, fractures and malalignment. High-signal-intensity(HSI) was observed on T2WI in 10 patients with myelopathy. HSI diminished postoperatively in the patients who improved clinically, and remained the same in one case whose conditions remained uncharged after decompression. Preliminary experience with Magnetic Resonance Imaging(MRI) in the evaluation of traumatic and degenerative cervical spine lesions reveal many advantages over the computed tomoography, plain radiographs and myelography. Futhermore, HSI of the spinal cord produced by compressive lessions appears to be an important indicator for predicting prognosis.