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1.
Skeletal Radiol ; 44(7): 971-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25833276

RESUMO

OBJECTIVE: To investigate the performance of a new CT software generating rib unfolded images for improved detection of rib osteolyses in patients with multiple myeloma. MATERIALS AND METHODS: One hundred sixteen patients who underwent whole-body reduced-dose multidetector computed tomography (WBRD-MDCT) for multiple myeloma diagnosis and during follow-up were retrospectively evaluated. Nonenhanced CT scans with 5- and 1-mm slice thickness were interpreted by two readers with focus on detection of rib involvement (location, number, fracture). Image analysis of "unfolded," 1-mm-based CT rib images was subsequently undertaken. We classified the number of lytic bone lesions into 0, 1, 2, <5, <10 and ≥10. For all three data sets the reading time was registered. RESULTS: An approximated sum of 6,727 myeloma-related rib lesions was found. On a patient-based analysis, CT (5 mm), CT (1 mm) and CT (1 mm "unfolded rib") yielded a sensitivity, specificity and accuracy of 79.7/94.7/87.1, 88.1/93/90.5 and 98.3/96.5/97.4, respectively. In a lesion-based analysis, the sensitivity, specificity and accuracy of the three evaluations were 69.7/87.2/70.5, 79.8/55.9/78 and 96.5/89.7/96.1. Mean reading time for 5 mm/1 mm axial images and unfolded images was 178.7/215.1/90.8 s, respectively. CONCLUSION: The generation of "unfolded rib" images improves detection of rib involvement in patients with multiple myeloma and significantly reduces reading time.


Assuntos
Neoplasias Ósseas/diagnóstico por imagem , Mieloma Múltiplo/diagnóstico por imagem , Intensificação de Imagem Radiográfica/métodos , Costelas/diagnóstico por imagem , Software , Tomografia Computadorizada por Raios X/métodos , Idoso , Feminino , Humanos , Masculino , Variações Dependentes do Observador , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Validação de Programas de Computador
2.
PLoS One ; 10(3): e0120357, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25768940

RESUMO

Magnetic resonance imaging enhances the clinical diagnosis of Menière's disease. This is accomplished by in vivo detection of endolymphatic hydrops, which are graded using different semi-quantitative grading systems. We evaluated an established, semi-quantitative endolymphatic hydrops score and with a quantitative method for volumetric assessment of the endolymphatic size. 11 patients with Menière's disease and 2 healthy subjects underwent high resolution endolymphatic hydrops 3 Tesla MRI with highly T2 weighted FLAIR and T2DRIVE sequences. The degree of endolymphatic hydrops was rated semi-quantitatively and compared to the results of 3D-volumetry. Moreover, the grade of endolymphatic hydrops was correlated with pure tone audiometry. Semi-quantitative grading and volumetric evaluation of the endolymphatic hydrops are in accordance (r = 0.92) and the grade of endolymphatic hydrops correlates with pure tone audiometry. Patients with a sickness duration of ≥ 30 months showed a significant higher total labyrinth fluid volume (p = 0.03). Fast, semi-quantitative evaluation of endolymphatic hydrops is highly reliable compared to quantitative/volumetric assessment. Endolymphatic space is significantly higher in patients with longer sickness duration.


Assuntos
Endolinfa/metabolismo , Doença de Meniere/diagnóstico , Doença de Meniere/patologia , Audiometria de Tons Puros , Gadolínio/farmacologia , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética/métodos , Estatísticas não Paramétricas
3.
Acad Radiol ; 22(4): 505-12, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25586709

RESUMO

RATIONALE AND OBJECTIVES: To evaluate the performance of a dedicated computed tomography (CT) software called "bone reading" generating rib unfolded images for improved detection of rib metastases in patients with lung cancer in comparison to readings of 5- and 1-mm axial CT images and (18)F-Fluordeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT). MATERIALS AND METHODS: Ninety consecutive patients who underwent (18)F-FDG-PET/CT and chest CT scanning between 2012 and 2014 at our institution were analyzed retrospectively. Chest CT scans with 5- and 1-mm slice thickness were interpreted blindly and separately focused on the detection of rib metastases (location, number, cortical vs. medullary, and osteoblastic vs. sclerotic). Subsequent image analysis of unfolded 1 mm-based CT rib images was performed. For all three data sets the reading time was registered. Finally, results were compared to those of FDG-PET. Validation was based on FDG-PET positivity for osteolytic and mixed osteolytic/osteoblastic focal rib lesions and follow-up for sclerotic PET-negative lesions. RESULTS: A total of 47 metastatic rib lesions were found on FDG-PET/CT plus another 30 detected by CT bone reading and confirmed by follow-up CT. Twenty-nine lesions were osteolytic, 14 were mixed osteolytic/osteoblastic, and 34 were sclerotic. On a patient-based analysis, CT (5 mm), CT (1 mm), and CT (1-mm bone reading) yielded a sensitivity, specificity, and accuracy of 76.5/97.3/93, 81.3/97.3/94, and 88.2/95.9/92, respectively. On segment-based (unfolded rib) analysis, the sensitivity, specificity, and accuracy of the three evaluations were 47.7/95.7/67, 59.5/95.8/77, and 94.8/88.2/92, respectively. Reading time for 5 mm/1 mm axial images and unfolded images was 40.5/50.7/21.56 seconds, respectively. CONCLUSIONS: The use of unfolded rib images in patients with lung cancer improves sensitivity and specificity of rib metastasis detection in comparison to 5- and 1-mm CT slice reading. Moreover, it may reduce the reading time.


Assuntos
Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/secundário , Fluordesoxiglucose F18 , Neoplasias Pulmonares/patologia , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Idoso , Feminino , Humanos , Masculino , Imagem Multimodal , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Costelas/diagnóstico por imagem , Sensibilidade e Especificidade , Software
4.
Chin J Traumatol ; 17(1): 25-30, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24506919

RESUMO

OBJECTIVE: Detection of abdominal injury is a very important component in trauma management, so a precise assessment of liver and spleen injuries including their severity degree is necessary. There is a good case to believe that in emergency situations the radiologists' performance may profit from a systematic approach using established scoring systems. Score systems as the organ injury scale (OIS) drawn up by the American Association for the Surgery of Trauma are a valuable guidance for objective trauma assessment. Aim of this study was to evaluate retrospectively whether a structured approach using the OIS may help improve trauma assessment. METHODS: Fifty-three patients, 38 male and 15 female who underwent CT and laparotomy after abdominal trauma were included in this study. The laparotomy was performed by experienced surgeons with a minimum experience of 6 years. While the original CT reports were written by different radiologists with a minimum experience of 3 years, and then a radiologist with experience of 4 years reviewed the same original CT pictures, resulting in the structured report. Both the original and structured CT results on liver and spleen injuries were transferred into OIS grades. Finally, the initial and structured CT results were compared with the intraoperative findings gathered from the surgery report. RESULTS: Regarding the original CT report we found a mean divergence of 0.68 ± 0.8 (r=0.45) to the OIS finding in the surgery report for liver injuries (0.69 ± 1.17 for spleen injuries; r=0.69). In comparison with the structured approach, where we detected a divergence of 0.8 ± 0.68; r=0.63 (0.47 ± 0.77 for spleen injuries; r=0.91), there was no significant difference. However we detected a lower rate of over-diagnosis in structured approaches. CONCLUSION: Our study shows that a structured approach to triage abdominal trauma using an imaging checklist does not lead to a significantly higher detection rate, but a nonsignificant trend to reduce the rate of over-diagnoses, thus being more precise in grading the severity grade. Concerning the bias by retrospective study design, further prospective investigations are needed to evaluate the impact of trauma scores on the workflow in emergency department procedure as structured reporting systems are a valuable guidance in other radiological disciplines.


Assuntos
Fígado/diagnóstico por imagem , Fígado/lesões , Baço/diagnóstico por imagem , Baço/lesões , Índices de Gravidade do Trauma , Adulto , Feminino , Humanos , Masculino , Radiografia , Estudos Retrospectivos
5.
Magn Reson Med Sci ; 12(4): 261-9, 2013 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-24172793

RESUMO

PURPOSE: Many inner ear disorders, including Ménière's disease, are believed to be based on endolymphatic hydrops. We evaluated a newly proposed method for semi-quantification of endolymphatic size in patients with suspected endolymphatic hydrops that uses 2 kinds of processed magnetic resonance (MR) images. METHODS: Twenty-four consecutive patients underwent heavily T2-weighted (hT2W) MR cisternography (MRC), hT2W 3-dimensional (3D) fluid-attenuated inversion recovery (FLAIR) with inversion time of 2250 ms (positive perilymph image, PPI), and hT2W-3D-IR with inversion time of 2050 ms (positive endolymph image, PEI) 4 hours after intravenous administration of single-dose gadolinium-based contrast material (IV-SD-GBCM). Two images were generated using 2 new methods to process PPI, PEI, and MRC. Three radiologists contoured the cochlea and vestibule on MRC, copied regions of interest (ROIs) onto the 2 kinds of generated images, and semi-quantitatively measured the size of the endolymph for the cochlea and vestibule by setting a threshold pixel value. RESULTS: Each observer noted a strong linear correlation between endolymphatic size of both the cochlea and vestibule of the 2 kinds of generated images. The Pearson correlation coefficients (r) were 0.783, 0.734, and 0.800 in the cochlea and 0.924, 0.930, and 0.933 in the vestibule (P<0.001, for all). In both the cochlea and vestibule, repeated-measures analysis of variance showed no statistically significant difference between observers. CONCLUSION: Use of the 2 kinds of generated images generated from MR images obtained 4 hours after IV-SD-GBCM might enable semi-quantification of endolymphatic size with little observer dependency.


Assuntos
Endolinfa/citologia , Ducto Endolinfático/patologia , Hidropisia Endolinfática/patologia , Gadolínio DTPA , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Meios de Contraste/administração & dosagem , Feminino , Gadolínio DTPA/administração & dosagem , Humanos , Aumento da Imagem/métodos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
6.
Naunyn Schmiedebergs Arch Pharmacol ; 380(6): 531-8, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19830405

RESUMO

Vestibular vertigo may be induced by increases in the endolymphatic pressure that activate pressure-dependent K(+) currents (I(K,p)) in vestibular hair cells. I(K,p) have been demonstrated to modulate transmitter release and are inhibited by low concentrations of cinnarizine. Beneficial effects against vestibular vertigo of cinnarizine have been attributed to its inhibition of calcium currents. Our aim was to determine the extent by which the inhibition of I(K,p) by cinnarizine may alter the voltage response to stimulating currents and to analyze whether such alterations may be sufficient to modulate the activation of Ca(2+) currents and transmitter release. Vestibular type II hair cells from guinea pigs were studied using the whole-cell patch-clamp technique. In current clamp, voltage responses to trains of stimulating currents were recorded. In voltage clamp, transmitter release was assessed from changes in the cell capacitance, as calculated from the phase shift during application of sine waves. Cinnarizine (0.05-3 microM) concentration dependently reversed the depressing effects of increases in the hydrostatic pressure (from 0.2 to 0.5 cm H(2)O) on the voltage responses to stimulating currents. Voltage protocols that simulated these responses were applied in voltage clamp and revealed a significantly enhanced transmitter release in conditions mimicking an inhibition of I(K,p). Cinnarizine (< or =0.5 microM) did not inhibit calcium currents. We conclude that cinnarizine, in pharmacologically relevant concentrations, enhances transmitter release in the presence of elevated hydrostatic pressure by an indirect mechanism, involving inhibition of I(K,p), enhancing depolarization, and increasing the voltage-dependent activation of Ca(2+) currents, without directly affecting Ca(2+) current.


Assuntos
Cálcio/metabolismo , Cinarizina/farmacologia , Células Ciliadas Vestibulares/efeitos dos fármacos , Canais de Potássio/metabolismo , Animais , Bloqueadores dos Canais de Cálcio/administração & dosagem , Bloqueadores dos Canais de Cálcio/farmacologia , Cinarizina/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Cobaias , Pressão Hidrostática , Doença de Meniere/tratamento farmacológico , Doença de Meniere/fisiopatologia , Técnicas de Patch-Clamp
7.
Pflugers Arch ; 458(2): 379-87, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19084993

RESUMO

Vestibular type II hair cells respond to increases in the hydrostatic pressure with pressure-dependent K(+) currents. We examined whether such currents may modulate transmitter release (assessed as membrane capacitance increments) by altering membrane potentials and voltage-gated Ca(2+) currents. Capacitance increments were dependent on voltage-gated Ca(2+) influx. Stimulating currents (0.7 nA) in current clamp induced depolarisations that were more negative by 8.7 +/- 2.1 mV when the bath height was elevated from 0.2 to 0.5 cm. In voltage clamp, protocols were used that simulated the time course of the membrane potential in current clamp at either low (control) or high hydrostatic pressure (high bath). The low bath protocol induced significantly larger Ca(2+) currents and increases in capacitance than the high bath protocol. We conclude that pressure-dependent K(+) currents may alter the voltage response of vestibular hair cells to an extent critical for Ca(2+) currents and transmitter release. This mechanism may contribute to vestibular dysfunction in Meniere's disease.


Assuntos
Células Ciliadas Vestibulares/fisiologia , Potenciais da Membrana/efeitos dos fármacos , Potássio/metabolismo , Animais , Cálcio/metabolismo , Capacitância Elétrica , Estimulação Elétrica , Feminino , Cobaias , Pressão Hidrostática , Técnicas de Patch-Clamp
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