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1.
Phys Rev Lett ; 132(5): 051002, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38364164

RESUMEN

We present the measurement of the cosmic ray proton spectrum from 50 TeV to 1.3 PeV using 7.81×10^{6} extensive air shower events recorded by the ground-based GRAPES-3 experiment between 1 January 2014 and 26 October 2015 with a live time of 460 day. Our measurements provide an overlap with direct observations by satellite and balloon-based experiments. The electromagnetic and muon components in the shower were measured by a dense array of plastic scintillator detectors and a tracking muon telescope, respectively. The relative composition of the proton primary from the air shower data containing all primary particles was extracted using the multiplicity distribution of muons which is a sensitive observable for mass composition. The observed proton spectrum suggests a spectral hardening at ∼166 TeV and disfavors a single power law description of the spectrum up to the Knee energy (∼3 PeV).

2.
Science ; 382(6673): 903-907, 2023 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-37995237

RESUMEN

Cosmic rays are energetic charged particles from extraterrestrial sources, with the highest-energy events thought to come from extragalactic sources. Their arrival is infrequent, so detection requires instruments with large collecting areas. In this work, we report the detection of an extremely energetic particle recorded by the surface detector array of the Telescope Array experiment. We calculate the particle's energy as [Formula: see text] (~40 joules). Its arrival direction points back to a void in the large-scale structure of the Universe. Possible explanations include a large deflection by the foreground magnetic field, an unidentified source in the local extragalactic neighborhood, or an incomplete knowledge of particle physics.

4.
Tech Coloproctol ; 25(1): 69-74, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32815047

RESUMEN

BACKGROUND: Transanal (Ta) pelvic exenteration is a promising, minimally invasive method for treating locally advanced colorectal cancer. However, since it is technically difficult to perform, Ta pelvic exenteration is rarely reported in locally advanced T4 rectal cancer cases. The aim of this study was to evaluate the feasibility of transabdominal laparoscopy-assisted Ta pelvic exenteration. METHODS: Six patients (4 males and 2 females) had laparoscopy-assisted Ta total or posterior pelvic exenteration for locally advanced or recurrent colorectal cancer cases at the Nagasaki University Hospital between September 2018 and August 2019. Clinical and pathological outcomes were measured and analyzed. RESULTS: The median operation time and intraoperative blood loss were 481 (range 456-709) minutes and 352.5 (range 257-1660) ml, respectively. R0 resection was achieved in all cases, and no patient required open surgery. Two patients had grade 3 complications (Clavien-Dindo) or higher. There was no mortality, and no reoperation was required. CONCLUSIONS: The results suggest that laparoscopic-assisted Ta pelvic exenteration is an acceptable procedure, may help overcome the current technical difficulties, and may improve outcomes in patients with locally advanced rectal cancer.


Asunto(s)
Laparoscopía , Exenteración Pélvica , Neoplasias del Recto , Estudios de Factibilidad , Femenino , Humanos , Masculino , Recurrencia Local de Neoplasia/cirugía , Neoplasias del Recto/cirugía , Estudios Retrospectivos
6.
J Dent Res ; 97(6): 701-708, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29513618

RESUMEN

Head and neck cancer is the sixth most common cancer worldwide. It remains one of the leading causes of death, and its early detection is crucial. Liquid biopsy has emerged as a promising tool for detecting and monitoring the disease status of patients with early and advanced cancers. Circulating tumor DNA (ctDNA), circulating tumor cells (CTCs), and exosomal miRNAs have received enormous attention because of their apparent clinical implications. Analyses of these circulating biomarkers have paved the way for novel therapeutic approaches and precision medicine. A growing number of reports have implicated the use of circulating biomarkers for detection, treatment planning, response monitoring, and prognosis assessment. Although these new biomarkers can provide a wide range of possible clinical applications, no validated circulating biomarkers have yet been integrated into clinical practice for head and neck cancer. In this review, we summarize the current knowledge of circulating biomarkers in this field, focusing on their feasibility, limitations, and key areas of clinical applications. We also highlight recent advances in salivary diagnostics and their potential application in head and neck cancer.


Asunto(s)
Neoplasias de Cabeza y Cuello/diagnóstico , Biopsia Líquida , Biomarcadores de Tumor/análisis , ADN de Neoplasias/análisis , Neoplasias de Cabeza y Cuello/patología , Humanos , Biopsia Líquida/métodos , Saliva/química
7.
Neurogastroenterol Motil ; 29(12)2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28631871

RESUMEN

BACKGROUNDS: Chronic intestinal pseudo-obstruction (CIPO) is an intractable rare digestive disease manifesting persistent small bowel distension without any mechanical cause. Intestinal decompression is a key treatment, but conventional method including a trans-nasal small intestinal tube is invasive and painful. Therefore, a less invasive and tolerable new decompression method is urgently desired. We conducted a pilot study and assessed the efficacy and safety of percutaneous endoscopic gastro-jejunostomy (PEG-J) decompression therapy in CIPO patients. METHODS: Seven definitive CIPO patients (2 males and 5 females) were enrolled. All patients received PEG-J decompression therapy. The number of days with any abdominal symptoms in a month (NODASIM), body mass index (BMI), serum albumin level (Alb), and small intestinal volume before and after PEG-J were compared in all patients. RESULTS: Percutaneous endoscopic gastro-jejunostomy was well tolerated and oral intake improved in all patients. NODASIM has significantly decreased (24.3 vs 9.3 days/months) and BMI/Alb have significantly increased (14.9 vs 17.2 kg/m2 and 2.6 vs 3.8 g/dL, respectively), whereas total volume of the small intestine has not significantly reduced (4.05 vs 2.59 L, P=.18). Reflux esophagitis and chemical dermatitis were observed in one case but was successfully treated conservatively. CONCLUSIONS & INFERENCES: Percutaneous endoscopic gastro-jejunostomy decompression therapy can contribute greatly to improvement of abdominal symptoms and nutritional status in CIPO patients. Although sufficient attention should be paid to acid reflux symptoms, PEG-J has the potential to be a non-invasive novel decompression therapy for CIPO available at home. However, accumulation of more CIPO patients and long-term observation are needed (UMIN000017574).


Asunto(s)
Endoscopía Gastrointestinal/métodos , Gastrostomía/métodos , Seudoobstrucción Intestinal/cirugía , Yeyunostomía/métodos , Adulto , Anciano , Enfermedad Crónica , Descompresión Quirúrgica/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Adulto Joven
8.
Rev Sci Instrum ; 87(5): 053309, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-27250416

RESUMEN

For evaluation of on-site dosimetry and process design in industrial use of ultra-low energy electron beam (ULEB) processes, we evaluate the energy deposition using a thin radiochromic film and a Monte Carlo simulation. The response of film dosimeter was calibrated using a high energy electron beam with an acceleration voltage of 2 MV and alanine dosimeters with uncertainty of 11% at coverage factor 2. Using this response function, the results of absorbed dose measurements for ULEB were evaluated from 10 kGy to 100 kGy as a relative dose. The deviation between the responses of deposit energy on the films and Monte Carlo simulations was within 15%. As far as this limitation, relative dose estimation using thin film dosimeters with response function obtained by high energy electron irradiation and simulation results is effective for ULEB irradiation processes management.

9.
Neuropathol Appl Neurobiol ; 42(3): 242-54, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26538301

RESUMEN

AIMS: A hexanucleotide expansion in C9orf72 is the major genetic cause of inherited behavioural variant Frontotemporal dementia (bvFTD) and motor neurone disease (MND), although the pathological mechanism(s) underlying disease remains uncertain. METHODS: Using antibodies to poly-GA, poly-GP, poly-GR, poly-AP and poly-PR proteins, we examined sections of cerebral cortex, hippocampus, thalamus, cerebellum and spinal cord, from 20 patients with bvFTD and/or MND bearing an expansion in C9orf72 for aggregated deposits of dipeptide repeat proteins (DPR). RESULTS: Antibodies to poly-GA, poly-GP and poly-GR detected numerous rounded cytoplasmic inclusions (NCI) within granule cells of hippocampal dentate gyrus and those of the cerebellum, as well as 'star-burst' shaped NCI in pyramidal neurones of CA3/4 region of hippocampus. NCI were uncommon in Purkinje cells, and only very rarely seen in anterior horn cells. Poly-PA antibody detected occasional NCI within CA3/4 neurones alone, whereas poly-PR antibody did not identify any NCI but immunostained the nucleus of anterior horn cells, CA3/4 neurones and Purkinje cells, in patients with or without expansion in C9orf72, as well as in normal controls. Poly-GA antibody generally detected more DPR than poly-GP, which in turn was greater than poly-GR. All patients with bvFTD + MND or MND showed plentiful p62/TDP-43 positive inclusions in remaining anterior horn cells. CONCLUSION: Degeneration and loss of anterior horn cells associated with expansions in C9orf72 occurs in the absence of DPR, and implies that changes involving loss of nuclear staining for and a cytoplasmic aggregation of TDP-43 are more likely to be the cause of this.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Degeneración Lobar Frontotemporal/patología , Enfermedad de la Neurona Motora/patología , Degeneración Nerviosa/patología , Proteínas/genética , Anciano , Proteína C9orf72 , Expansión de las Repeticiones de ADN , Dipéptidos , Femenino , Degeneración Lobar Frontotemporal/genética , Humanos , Inmunohistoquímica , Cuerpos de Inclusión/metabolismo , Cuerpos de Inclusión/patología , Masculino , Persona de Mediana Edad , Enfermedad de la Neurona Motora/genética , Degeneración Nerviosa/genética , Neuronas/patología
10.
Rev Sci Instrum ; 83(8): 083112, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22938279

RESUMEN

We have developed a quick-scanning x-ray absorption fine structure (QXAFS) system and installed it at the recently constructed synchrotron radiation beamline BL33XU at the SPring-8. Rapid acquisition of high-quality QXAFS data was realized by combining a servo-motor-driven Si channel-cut monochromator with a tapered undulator. Two tandemly aligned monochromators with channel-cut Si(111) and Si(220) crystals covered energy ranges of 4.0-28.2 keV and 6.6-46.0 keV, respectively. The system allows the users to adjust instantly the energy ranges of scans, the starting angles of oscillations, and the frequencies. The channel-cut crystals are cooled with liquid nitrogen to enable them to withstand the high heat load from the undulator radiation. Deformation of the reflecting planes is reduced by clamping each crystal with two cooling blocks. Performance tests at the Cu K-edge demonstrated sufficiently high data quality for x-ray absorption near-edge structure and extended x-ray absorption fine-structure analyses with temporal resolutions of up to 10 and 25 ms, respectively.

11.
Neurogastroenterol Motil ; 24(12): 1083-e564, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22882753

RESUMEN

BACKGROUND: Oral sumatriptan administration has been reported to delay gastric emptying after liquid meals. The aim of this study was to determine whether delayed gastric emptying is caused by enhanced gastric accommodation, impaired antral contractions, or both using ultrasonography. METHODS: Ten healthy volunteers were enrolled in this randomized two-way crossover study. After overnight fasting, the subjects received the liquid meal 60 min after ingesting a 50 mg sumatriptan tablet with 50 mL of water or 50 mL of water alone (control). The cross-sectional area of the proximal stomach was measured in a supine position after every 100 mL. The frequency and amplitude of the antral contractions were measured in a slightly backward sitting position. The intragastric distribution of the liquid meal was assessed by calculating the proximal stomach/distal stomach ratio (prox/distal ratio). KEY RESULTS: The cross-sectional area after drinking 100, 200, and 300 mL of the liquid meal (oral sumatriptan vs control) was 34.49 vs 15.11 cm(2) (P = 0.0051), 48.00 vs 30.61 cm(2) (P = 0.0166), and 58.67 vs 47.19 cm(2) (P = 0.0125), respectively. There was no significant difference in the amplitude of contractions, contraction cycle, motility index, and prox/distal ratio (97.15 vs 97.93%, P = 0.0745; 19.42 vs 19.5 s, P= 0.8590; and 887.58 vs 889.22, P = 0.5751; 9.75 vs 8.41, P = 0.8785; respectively). CONCLUSIONS & INFERENCES: Oral sumatriptan administration enhanced gastric accommodation after the ingestion of liquid nutrients, but had no significant effect on antral contractions or intragastric distribution in healthy subjects.


Asunto(s)
Vaciamiento Gástrico/efectos de los fármacos , Estómago/efectos de los fármacos , Estómago/diagnóstico por imagen , Sumatriptán/farmacología , Vasoconstrictores/farmacología , Estudios Cruzados , Femenino , Humanos , Masculino , Contracción Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Ultrasonografía , Adulto Joven
12.
Colorectal Dis ; 14(10): e740-6, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22709354

RESUMEN

AIM: A case-controlled study was performed to investigate the association of colonic angiectasia with other conditions and to identify risk factors for bleeding. METHOD: Information was collected from all patients who underwent colonoscopy at our hospital between January 2008 and December 2010. Data on 90 individuals with angiectasia [58 men; median age 69 (26-92) years] were compared with those of 180 individuals without angiectasia, matched for gender and age. RESULTS: Multivariate analysis showed that occult gastrointestinal bleeding [odds ratio (OR) 2.523; 95% confidence interval (CI) 1.238-5.142], liver cirrhosis (OR 13.195; 95% CI 3.502-49.711), chronic renal failure (OR 6.796; 95% CI 1.598-28.904) and valvular heart disease (OR 6.425; 95% CI 1.028-40.165) were identified as significant predictors of the presence of colonic angiectasia. Eight patients were diagnosed with bleeding from angiectasia. Cardiovascular disease (OR 22.047; 95% CI 1.063-457.345) and multiple angiectasias (P-value 0.0019) were identified as significant risk factors for active bleeding. Medication and a large size were not associated with an increased risk of bleeding. CONCLUSION: The presence of colonic angiectasia was associated with valvular heart disease, liver cirrhosis and chronic renal failure. Valvular heart disease and multiple lesions increased the risk of bleeding.


Asunto(s)
Angiodisplasia/etiología , Enfermedades del Colon/etiología , Hemorragia Gastrointestinal/etiología , Adulto , Anciano , Anciano de 80 o más Años , Angiodisplasia/diagnóstico , Estudios de Casos y Controles , Enfermedades del Colon/diagnóstico , Colonoscopía , Femenino , Hemorragia Gastrointestinal/diagnóstico , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Retrospectivos , Factores de Riesgo
13.
Med Phys ; 39(6Part13): 3758, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28517353

RESUMEN

PURPOSE: A commercial 6D carbon fiber radiotherapy treatment couch (Imaging Couch Top, BrainLAB) has recently been reported to attenuate photon beams and increase skin dose. To prevent skin toxicity and ensure the target dose, it is important to correct the attenuation properties of the treatment couch with the treatment planning system (TPS). In this study, we evaluated the accuracy of dose attenuation correction by a virtual couch technique integrated into the TPS. METHODS: A virtual couch was modeled in the TPS (Eclipse v10.0, Varian). The CT value of the virtual couch was assigned with the CT value of the kilovoltage-CT images of the treatment couch. A phantom consisting of several plastic water slabs was created. We selected an evaluation point within the phantom on the couch structure at a 9 cm depth from the couch surface, which was placed at the isocenter. The doses at this point were calculated and measured at several gantry angles, from 120 degree to 240 degree at 10 degree steps, and each field size was 10 cm × 10 cm. The prescribed dose was 100 monitor units for 6/10 MV photon beams and 6 MV-SRS mode (Trilogy Tx, Varian). Dose measurements were performed with an ion chamber. RESULTS: The largest difference between measured and calculated doses was 3.3% for a gantry angle of 120 degree and 6 MV-SRS mode. The average dose difference was within 1.6% for all gantry angles and photon beams. In the case without attenuation correction, the largest difference was 8.2% and the average difference was 5.2%. CONCLUSIONS: Use of the virtual couch technique in TPS accomplished sufficient accuracy for dose attenuation correction of the 6D carbon fiber treatment couch, and it is an effective method for clinical use.

15.
Clin Exp Rheumatol ; 28(1): 6-12, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20346231

RESUMEN

OBJECTIVES: To evaluate the safety and potential efficacy of tacrolimus for the treatment of patients with lupus nephritis and persistent proteinuria. METHODS: A total of 23 Japanese patients with lupus nephritis (21 females/2 males) were enrolled in this study. Patients were administered tacrolimus at a dose of 2-3 mg once daily after the evening meal for 6 months. The dose of tacrolimus was unchanged throughout the study period. Concomitant prednisolone therapy was unchanged or gradually tapered, while other immunosuppressants were stopped at the start of tacrolimus treatment. RESULTS: Tacrolimus was well tolerated, and none of the patients developed adverse drug reactions that required discontinuation of the study. Daily urinary protein loss, the U-prot/U-creat ratio, and serum albumin were significantly improved after 4 months, 3 months, and 1 month of treatment with tacrolimus (p<0.05), respectively, and the improvement persisted until 6 months. The serum complement hemolytic activity (CH50), complement C3 level, and CRP level were also significantly improved after treatment with tacrolimus (p<0.05). Improvement of the U-prot/U-creat ratio was most prominent for patients who were in WHO class IV. CONCLUSIONS: Tacrolimus is safe and effective as maintenance therapy for patients with lupus nephritis, at least for 6 months. A larger randomised, controlled trial over a longer period is needed to confirm these results.


Asunto(s)
Inmunosupresores/administración & dosificación , Nefritis Lúpica/tratamiento farmacológico , Proteinuria/tratamiento farmacológico , Tacrolimus/administración & dosificación , Adolescente , Adulto , Proteína C-Reactiva/metabolismo , Complemento C3/metabolismo , Ensayo de Actividad Hemolítica de Complemento , Quimioterapia Combinada , Femenino , Glucocorticoides/administración & dosificación , Humanos , Inmunosupresores/efectos adversos , Masculino , Persona de Mediana Edad , Prednisolona/administración & dosificación , Tacrolimus/efectos adversos , Resultado del Tratamiento , Adulto Joven
16.
Phytopathology ; 99(2): 209-16, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19159313

RESUMEN

Bacterial shoot blight (BSB) disease, caused by Pseudomonas syringae pv. theae, is a major bacterial disease of tea plants in Japan. BSB mainly occurs in the low-temperature season, and lesion formation by P. syringae pv. theae is enhanced by both low temperature and the presence of ice nucleation-active Xanthomonas campestris (INAX), which catalyzes ice formation at -2 to -4 degrees C and is frequently co-isolated with P. syringae pv. theae from tea plants. Low temperature is thus the most important environmental factor influencing the incidence of BSB; however, the effects of low temperature on infection of the host by P. syringae pv. theae and of environmental controls in fields on the occurrence of the disease are poorly understood. In this study, we show that ice formation on tea leaves by INAX enhanced P. syringae pv. theae invasion into leaf tissue. The natural incidence of BSB in the field was closely related to early autumn frost. Frost protection in late autumn, which prevented ice formation on tea plants, significantly decreased the incidence of BSB, and frost protection combined with bactericide application held the incidence under the economic threshold level. Our data indicate that environmental control in the field based on microbial interactions in the host offers a new strategy for plant disease control.


Asunto(s)
Agricultura , Camellia sinensis/microbiología , Ambiente , Enfermedades de las Plantas/microbiología , Pseudomonas syringae/clasificación , Antibacterianos/uso terapéutico , Control Biológico de Vectores , Hojas de la Planta/microbiología , Pseudomonas syringae/efectos de los fármacos , Estaciones del Año , Temperatura , Factores de Tiempo
17.
AJNR Am J Neuroradiol ; 29(9): 1652-7, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18583402

RESUMEN

BACKGROUND AND PURPOSE: Flow voids within the cavernous sinuses and/or certain venous drainage on spin-echo MR imaging and time-of-flight (TOF) flow enhancement on MR angiography (MRA) have indicated high-velocity shunt flow and have been used for screening patients with dural arteriovenous fistulas (DAVFs) of the cavernous sinuses. In this investigation, the capabilities of 3D dynamic MRA as a flow-independent approach and those of conventional MR imaging techniques were compared with selective angiography for the diagnosis of DAVFs of the cavernous sinuses. MATERIALS AND METHODS: This retrospective study involved 18 patients with angiographically proved DAVFs of the cavernous sinuses and 12 control subjects. Sixteen partially overlapping sequential MR images were acquired on contrast-enhanced 3D dynamic MRA between the petrosal bone and the orbital roof. Two experienced observers blinded to the clinical data and results of angiography independently graded 3D dynamic MRA, fast spin-echo T2-weighted imaging (FSE T2WI), and TOF MRA. RESULTS: The average area under the receiver operating characteristic curve values and interobserver kappa scores for the diagnosis of DAVFs on 3D dynamic MRA, FSE T2WI, and TOF MRA were 0.99, 0.89, and 0.95; and 0.92, 0.71, and 0.73, respectively. Those for the diagnosis of anterior, posterior, and retrograde cortical venous drainage on 3D dynamic MRA were 0.72, 0.95, and 0.81; and 0.56, 0.50, and 0.49, respectively. CONCLUSION: In this small series, screening 3D dynamic MRA directly demonstrates DAVFs of the cavernous sinuses and has improved diagnostic capability.


Asunto(s)
Seno Cavernoso , Malformaciones Vasculares del Sistema Nervioso Central/diagnóstico , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Angiografía por Resonancia Magnética , Adulto , Anciano , Anciano de 80 o más Años , Velocidad del Flujo Sanguíneo/fisiología , Estudios de Casos y Controles , Seno Cavernoso/fisiopatología , Malformaciones Vasculares del Sistema Nervioso Central/fisiopatología , Angiografía Cerebral , Venas Cerebrales/fisiopatología , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Curva ROC , Estudios Retrospectivos , Sensibilidad y Especificidad
18.
J Neurol Neurosurg Psychiatry ; 79(10): 1153-8, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18403441

RESUMEN

OBJECT: The pathophysiology of syringomyelia in Chiari type 1 malformations has not been clarified. Oedema-like spinal-cord swelling was recently reported in several pathological conditions, including Chiari type 1 malformations as a pre-syrinx state. However, the role of the pre-syrinx state in the development of syringomyelia is unknown. The purpose of this study is to investigate the parenchymal changes of the spinal cord in syringomyelia associated with Chiari type 1 malformations. METHODS: Pre- and postoperative MRI findings in 14 patients who underwent foramen magnum decompression in our institute were reviewed. The analysis was focused on differences in visualisation of the syrinx between T1- and T2-weighted images and abnormal parenchymal signal changes. There were 6 men and 8 women, aged from 6 to 79 years. No patients showed hydrocephalus. RESULTS: Twelve patients had large and expansive syrinx, whereas 2 patients showed small syrinx confined to the centre of the spinal cord. T2-weighted images displayed significantly larger intramedullary abnormal signal areas. Nine patients showed parenchymal hyperintensity areas around the enlarged central canal or base of the posterior white columns adjacent to the syringomyelic cavity. Such parenchymal hyperintensity areas markedly diminished with reduction of the syrinx after surgery and were considered to be interstitial oedema. CONCLUSIONS: From this study, the interstitial oedema of the spinal cord commonly accompanies syringomyelia with Chiari type 1 malformations. Accumulation of the extracellular fluid due to disturbed absorption mechanisms may play an important role in the pathophysiology of syringomyelia associated with Chiari type 1 malformations.


Asunto(s)
Malformación de Arnold-Chiari/complicaciones , Edema/etiología , Enfermedades de la Médula Espinal/etiología , Siringomielia/etiología , Adolescente , Adulto , Anciano , Malformación de Arnold-Chiari/diagnóstico , Niño , Diagnóstico Diferencial , Edema/diagnóstico , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Enfermedades de la Médula Espinal/patología , Siringomielia/diagnóstico
19.
Minim Invasive Neurosurg ; 51(2): 91-4, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18401821

RESUMEN

The purpose of this study was to evaluate quantitatively the composition of carotid plaque by computed tomographic (CT) angiography and qualitatively by black blood magnetic resonance images (MRI). Thirty-eight patients with high-grade carotid artery stenosis were included in this study. Ultrasonography, CT angiography and black blood MRI of the cervical carotid artery were performed, and the CT number was measured in Hounsfield units (HU). The average CT number of the 15 unstable plaques (39.5%) was 27.7+/-7.5 HU and that of the 23 stable plaques (60.5%) was 60.4+/-20.8 HU (p=0.0001). In the 23 patients with stable plaque, 21 demonstrated isointensity in T (1)- and T (2)-weighted images in the black blood MRI (p=0.0001). By using CT angiography and MRI, precise images of the pathology of the carotid arterial wall can be obtained. It is possible to evaluate the components of carotid artery plaque with high reliability by quantification of the CT number in CT angiography and performing black blood MRI as well as carotid ultrasonography.


Asunto(s)
Estenosis Carotídea/diagnóstico por imagen , Estenosis Carotídea/patología , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Arterias Carótidas/diagnóstico por imagen , Arterias Carótidas/patología , Angiografía Cerebral/métodos , Endarterectomía Carotidea/métodos , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Cuidados Preoperatorios/métodos , Ultrasonografía Doppler/métodos
20.
Interv Neuroradiol ; 14(1): 39-43, 2008 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-20557784

RESUMEN

SUMMARY: The purpose of this study was to evaluate the composition of a carotid plaque quantitatively by computed tomography (CT) angiography and qualitatively by black blood magnetic resonance imaging (MRI). Thirty-eight patients with high-grade carotid artery stenosis were included in this study. Ultrasonography, CT angiography and black blood MRI of the cervical carotid artery were performed, and the CT number was measured in Hounsfield units (HU). The average CT number of the 15 unstable plaques (39.5%) was 27.7 +/- 7.5 HU and that of the 23 stable plaques (60.5%) was 60.4 +/- 20.8 HU (p < 0.0001). In the 23 patients with stable plaque, 21 demonstrated isointensity in T1 and T2 in the black blood MRI (p < 0.0001). By using CT angiography and MRI, precise images of the pathology of the carotid arterial wall can be obtained. It is possible to evaluate the components of a carotid artery plaque with high reliability by quantification of the CT number in CT angiography and performing black blood MRI as well as in carotid ultrasonography.

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