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1.
BMC Med Imaging ; 22(1): 80, 2022 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-35501705

RESUMO

PURPOSE: To compare the diagnostic performance of deep learning models using convolutional neural networks (CNN) with that of radiologists in diagnosing endometrial cancer and to verify suitable imaging conditions. METHODS: This retrospective study included patients with endometrial cancer or non-cancerous lesions who underwent MRI between 2015 and 2020. In Experiment 1, single and combined image sets of several sequences from 204 patients with cancer and 184 patients with non-cancerous lesions were used to train CNNs. Subsequently, testing was performed using 97 images from 51 patients with cancer and 46 patients with non-cancerous lesions. The test image sets were independently interpreted by three blinded radiologists. Experiment 2 investigated whether the addition of different types of images for training using the single image sets improved the diagnostic performance of CNNs. RESULTS: The AUC of the CNNs pertaining to the single and combined image sets were 0.88-0.95 and 0.87-0.93, respectively, indicating non-inferior diagnostic performance than the radiologists. The AUC of the CNNs trained with the addition of other types of single images to the single image sets was 0.88-0.95. CONCLUSION: CNNs demonstrated high diagnostic performance for the diagnosis of endometrial cancer using MRI. Although there were no significant differences, adding other types of images improved the diagnostic performance for some single image sets.


Assuntos
Aprendizado Profundo , Neoplasias do Endométrio , Neoplasias do Endométrio/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Radiologistas , Estudos Retrospectivos
2.
J Pediatr Hematol Oncol ; 42(1): e12-e17, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31688631

RESUMO

A number of cases have been reported in recent years regarding the use of proton beam therapy to mitigate adverse events affecting important cranial organs in cases of rhabdomyosarcoma at parameningeal sites. However, few reports have described the use of proton beam therapy as urgent radiotherapy for parameningeal rhabdomyosarcoma with intracranial extension. We treated 3 patients diagnosed with parameningeal rhabdomyosarcoma extending into the cranium who were assessed at other hospitals as suitable for urgent radiotherapy and transferred to our hospital for proton beam therapy. These patients comprised 2 boys and 1 girl 6 to 12 years of age at diagnosis, and proton beam therapy was started on days 5, 11, and 23 after diagnosis, respectively. Patients with parameningeal rhabdomyosarcoma extending into the cranium can be transferred to institutions equipped to perform proton beam therapy. To minimize the interval to starting therapy, medical information should be shared with institutions capable of providing such therapy as soon as the possibility of intracranial soft-tissue sarcoma is recognized. Proton beam therapy is 1 option for radiotherapy in cases of intracranial rhabdomyosarcoma.


Assuntos
Neoplasias Encefálicas/radioterapia , Terapia com Prótons , Rabdomiossarcoma/radioterapia , Criança , Feminino , Humanos , Masculino
3.
Pol J Radiol ; 85: e163-e168, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32322323

RESUMO

PURPOSE: To plan a treatment strategy for a spinal arteriovenous shunt (SAVS), identifying the artery of Adamkiewicz (AKA) and its origin is indispensable. However, detecting the AKA is very difficult in patients with an SAVS when using computed tomography angiography (CTA) by the usual method to find the hairpin curved artery because dilated drainage veins nearly always coexist with the hairpin curved AKA. We designed a method to identify the AKA by focusing on the diameter and pathway of the anterior radiculomedullary arteries (RMAs). MATERIAL AND METHODS: Seven consecutive patients with an SAVS were surveyed. They underwent contrast-enhanced CTA and conventional angiography from January 2009 to December 2012. Two readers evaluated the CTA images and assumed that the AKA was the artery that ran through the anterior portion of the neural foramen and continued to pass on the ventral side of the spinal cord. RESULTS: Among the seven patients, nine AKAs were detected with conventional angiography. When using our method, seven AKAs and six AKAs were identified on CTA by Reader 1 and Reader 2, respectively. The average sensitivity was 72.3%, and the specificity, accuracy, positive predictive value, and negative predictive value were sufficiently high (i.e. > 85%) for both readers. The kappa value for detecting the AKA was 0.98. CONCLUSIONS: Detecting the origin of the AKA with CTA is challenging in patients with an SAVS. However, focusing on the diameter and pathway of the RMAs may allow successful identification.

4.
Childs Nerv Syst ; 35(9): 1615-1619, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30796559

RESUMO

Primary intracranial germinoma is a rare central nervous system tumor that usually arises in the pineal and the supra-sellar region. Here, we report a rare case of primary intracavernous sinus germinoma with an atypical extension pattern, with a comparison to germinomas originating from the cavernous sinus as described in the existing literature. A 12-year-old boy was admitted to our hospital with the chief complaint of the left-side ptosis and double vision. Magnetic resonance imaging showed homogenous enhanced mass lesion in the pineal region together with mass lesions in the lateral ventricle, left cavernous sinus, and temporal lobe, extending into the left masticator space. The enhanced mass in the intracavernous sinus originated from the cavernous sinus. Endoscopic third ventriculostomy and tumor biopsy was done. Pathological diagnosis was pure germinoma. After six courses of chemotherapy followed by radiation therapy, all the lesions decreased in size significantly. Only faint enhancement around the masticator space remained. We report a rare case of a germinoma that developed mainly in the cavernous sinus with additional tumor masses in the pineal region, ventricles, and temporal lobe. Although the lesions shrank significantly on the post-chemoradiation imaging, a long follow-up is necessary not only to check for symptoms, but also monitor imaging findings for possible serial changes in the residual region of the masticator space.


Assuntos
Neoplasias Encefálicas/patologia , Seio Cavernoso/patologia , Germinoma/patologia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/cirurgia , Seio Cavernoso/diagnóstico por imagem , Seio Cavernoso/cirurgia , Criança , Germinoma/diagnóstico por imagem , Germinoma/cirurgia , Humanos , Imageamento por Ressonância Magnética , Masculino , Resultado do Tratamento , Ventriculostomia
5.
Rep Pract Oncol Radiother ; 23(5): 442-450, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30197580

RESUMO

AIM: To assess the feasibility of transferring to the University of Tsukuba Hospital for proton beam therapy (PBT) during intensive chemotherapy in children with Ewing sarcoma family of tumors (ESFT) who had been diagnosed and started their first-line treatment at prefectural or regional centers for pediatric oncology. BACKGROUND: The treatment of ESFT relies on a multidisciplinary approach using intensive neoadjuvant and adjuvant chemotherapies with surgery and radiotherapy. Multi-agent chemotherapy comprising vincristine, doxorubicin, cyclophosphamide, ifosfamide, and etoposide (VDC-IE) is widely used for ESFT, and the interval between each course is very important for maintaining the intensity and effect of chemotherapy. MATERIALS AND METHODS: Clinical information of patients who received PBT and VDC-IE between April 2009 and May 2016 was collected retrospectively. The intervals between each course of VDC-IE and adverse events were assessed. RESULTS: Fifteen patients were evaluated. No delays in the intervals of chemotherapy due to transfer were observed. There were no adverse events caused during/just after transfer and no increases in adverse events. The estimated 4-year overall and event-free survival rates were 94.6% and 84.8%, respectively. DISCUSSION: Although the results of efficacy are preliminary, survival rates were comparable with past studies. More experience and follow-up are required to further assess the efficacy of PBT for patients with ESFT. CONCLUSION: Multidisciplinary therapy for children with ESFT involving transfer to our hospital for PBT during VDC-IE was feasible without treatment delay or an increase in adverse events.

6.
Eur J Radiol ; 160: 110713, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36716548

RESUMO

PURPOSE: Cone-beam computed tomography (CBCT) is useful in the diagnosis of complications after neuro-endovascular treatment. However, the image quality of conventional CBCT is inferior to that of conventional CT. To solve this problem, a dual-axis butterfly CBCT available with an angiography suite has been developed. This study aimed to evaluate the image quality of this dual-axis butterfly CBCT compared to the conventional CBCT in the same patient. METHOD: We prospectively included patients who underwent scheduled neuro-endovascular treatment and performed conventional CBCT and novel dual-axis butterfly CBCT as a postoperative examination. We evaluated artifacts, brain contrast, and cortico-medullary junctions on a scoring system using a 5-point scale in which lower scores indicate better image quality. In addition, the white matter/gray matter ratio was calculated in selected brain lobe regions. RESULTS: Forty-seven cases (94 paired images) were enrolled. The novel dual-axis butterfly CBCT had significantly fewer supratentorial and infratentorial artifacts in the artifact evaluation. Similarly, contrast and cortico-medullary junction discrimination in the cerebral hemispheres scored significantly better in the butterfly scan in all regions. The white matter/gray matter ROI ratio was significantly higher in the novel dual-axis butterfly CBCT in the frontal and occipital lobes but not in the temporal lobe. CONCLUSIONS: Compared to conventional CBCT, the novel dual-axis butterfly CBCT showed supratentorial and infratentorial artifact reduction as well as improved contrast with the brain parenchyma and cerebrospinal fluid space and white matter/gray matter discrimination ability.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Melhoria de Qualidade , Humanos , Tomografia Computadorizada de Feixe Cônico/métodos , Artefatos , Encéfalo/diagnóstico por imagem , Imagens de Fantasmas , Processamento de Imagem Assistida por Computador/métodos , Algoritmos
7.
Breast Cancer ; 30(4): 637-646, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37020090

RESUMO

BACKGROUND: Invasive lobular carcinoma (ILC) grows diffusely in a single-cell fashion, sometimes presenting only subtle changes in preoperative imaging; therefore, axillary lymph node (ALN) metastases of ILC are difficult to detect using magnetic resonance imaging (MRI). Preoperative underestimation of nodal burden occurs more frequently in ILC than in invasive ductal carcinoma (IDC), however, the morphological assessment for metastatic ALNs of ILC have not fully been investigated. We hypothesized that the high false-negative rate in ILC is caused by the discrepancy in the MRI findings of ALN metastases between ILC and IDC and aimed to identify the MRI finding with a strong correlation with ALN metastasis of ILC. METHOD: This retrospective analysis included 120 female patients (mean ± standard deviation age, 57.2 ± 11.2 years) who underwent upfront surgery for ILC at a single center between April 2011 and June 2022. Of the 120 patients, 35 (29%) had ALN metastasis. Using logistic regression, we constructed prediction models based on MRI findings: primary tumor size, focal cortical thickening (FCT), cortical thickness, long-axis diameter (LAD), and loss of hilum (LOH). RESULTS: The area under the curves were 0.917 (95% confidence interval [CI] 0.869-0.968), 0.827 (95% CI 0.758-0.896), 0.754 (95% CI 0.671-0.837), and 0.621 (95% CI 0.531-0.711) for the FCT, cortical thickness, LAD, and LOH models, respectively. CONCLUSIONS: FCT may be the most relevant MRI finding for ALN metastasis of ILC, and although its prediction model may lead to less underestimation of the nodal burden, rigorous external validation is required.


Assuntos
Neoplasias da Mama , Carcinoma Ductal de Mama , Carcinoma Lobular , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Neoplasias da Mama/patologia , Metástase Linfática/diagnóstico por imagem , Metástase Linfática/patologia , Carcinoma Lobular/diagnóstico por imagem , Carcinoma Lobular/cirurgia , Carcinoma Lobular/patologia , Estudos Retrospectivos , Carcinoma Ductal de Mama/patologia , Linfonodos/patologia , Imageamento por Ressonância Magnética
8.
Jpn J Radiol ; 41(9): 938-946, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37027094

RESUMO

PURPOSE: Silent corticotroph pituitary adenomas (SCAs)/pituitary neuroendocrine tumors (PitNETs) are common non-functioning pituitary adenomas (NFAs)/PitNETs with a clinically aggressive course. This study aimed to investigate the ability of time-intensity analysis of dynamic magnetic resonance imaging (MRI) for distinguishing adrenocorticotropic hormone (ACTH)-positive SCAs and ACTH-negative SCAs from other NFAs. MATERIALS AND METHODS: We retrospectively evaluated the dynamic MRI findings of patients with NFAs. The initial slope of the kinetic curve (slopeini) obtained by dynamic MRI for each tumor was analyzed using a modified empirical mathematical model. The maximum slope of the kinetic curve (slopemax) was obtained by geometric calculation. RESULTS: A total of 106 patients with NFAs (11 ACTH-positive SCAs, 5 ACTH-negative SCAs, and 90 other NFAs) were evaluated. The kinetic curves of ACTH-positive SCAs had significantly lesser slopeini and slopemax compared with ACTH-negative SCAs (P = 0.040 and P = 0.001, respectively) and other NFAs (P = 0.018 and P = 0.035, respectively). Conversely, the slopeini and slopemax were significantly greater in ACTH-negative SCAs than in NFAs other than ACTH-negative SCAs (P = 0.033 and P = 0.044, respectively). In receiver operating characteristic analysis of ACTH-positive SCAs and other NFAs, the area under the curve (AUC) values for slopeini and slopemax were 0.762 and 0748, respectively. In predicting ACTH-negative SCAs, the AUC values for slopeini and slopemax were 0.784 and 0.846, respectively. CONCLUSIONS: Dynamic MRI can distinguish ACTH-positive SCAs and ACTH-negative SCAs from other NFAs.


Assuntos
Adenoma Hipofisário Secretor de ACT , Adenoma , Tumores Neuroendócrinos , Doenças da Hipófise , Neoplasias Hipofisárias , Humanos , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/patologia , Adenoma/diagnóstico por imagem , Adenoma/patologia , Corticotrofos/metabolismo , Corticotrofos/patologia , Estudos Retrospectivos , Tumores Neuroendócrinos/diagnóstico por imagem , Cinética , Adenoma Hipofisário Secretor de ACT/patologia , Hormônio Adrenocorticotrópico/metabolismo , Imageamento por Ressonância Magnética
9.
J Comput Assist Tomogr ; 36(1): 143-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22261785

RESUMO

PURPOSE: The purpose of this study was to evaluate cerebral blood flow through the bypass in operated patients with Moyamoya disease using multiphase selective arterial spin labeling (ASL) technique. MATERIALS AND METHODS: Fifteen surgically treated cerebral hemispheres from 11 patients with Moyamoya disease were included. Selective ASL examinations were performed during the early postoperative period (mean, 5.5 days) on 4 hemispheres and late postoperative period (mean, 332.7 days) on 15 hemispheres. The labeling slab was positioned at the bypassed external carotid artery and 5 slices in each of the 10 sequential phases were acquired using a 3-T scanner. RESULTS: Two of 4 early postoperative ASL examinations and all late postoperative ASL examinations demonstrated blood flow through the bypass. The remaining 2 early postoperative ASL examinations showed absence of blood flow; however, blood flow improved on follow-up examinations. CONCLUSION: Multiphase selective ASL technique can provide information about the dynamics of postoperative blood flow through the bypass in Moyamoya disease.


Assuntos
Revascularização Cerebral/métodos , Imageamento por Ressonância Magnética/métodos , Doença de Moyamoya/cirurgia , Adolescente , Adulto , Circulação Cerebrovascular , Criança , Feminino , Hemodinâmica , Humanos , Pessoa de Meia-Idade , Marcadores de Spin , Resultado do Tratamento
10.
Surg Neurol Int ; 13: 346, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36128097

RESUMO

Background: Intraosseous schwannomas are extremely rare and they have not yet been reported to occur in the clivus. We report a schwannoma in the clivus mimicking chordoma and review intraosseous schwannomas of the skull. Case Description: A 62-year-old man presented with gradually worsening hoarseness with dysphagia and atrophy of the left tongue, trapezius muscle, and sternocleidomastoid muscle. Magnetic resonance imaging showed that the tumor was mainly located in the clivus, and a computed tomography (CT) scan revealed an osteolytic lesion with expansion of the clivus and preservation of the bony cortex. Endoscopic endonasal surgery was performed to diagnose and treat symptoms. The tumor was subtotally removed without any complications. The histopathological findings revealed typical schwannoma, which showed Antoni A and Antoni B patterns positive for S100 protein. Based on the preoperative imaging, intraoperative and histopathological findings, the tumor was considered to be an intraosseous schwannoma in the clivus, and no recurrence was observed after 1 year of postoperative follow-up. Conclusion: Even though the intraosseous schwannoma in the clivus is uncommon, it should be considered as a differential diagnosis if an expansive lesion without destruction of the cortical bone is shown on CT as well as iso-hyperintensity on T2-weighted magnetic resonance imaging.

11.
Eur J Radiol ; 154: 110445, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35901601

RESUMO

PURPOSE: To assess the clinical effectiveness of temporal subtraction computed tomography (TS CT) using deep learning to improve vertebral bone metastasis detection. METHOD: This retrospective study used TS CT comprising bony landmark detection, bone segmentation with a multi-atlas-based method, and spatial registration of two images by a log-domain diffeomorphic Demons algorithm. Paired current and past CT images of 50 patients without vertebral metastasis, recorded during June 2011-September 2016, were included as training data. A deep learning-based method estimated registration errors and suppressed false positives. Thereafter, paired CT images of 40 cancer patients with newly developed vertebral metastases and 40 control patients without vertebral metastases were evaluated. Six board-certified radiologists and five radiology residents independently interpreted 80 paired CT images with and without TS CT. RESULTS: Records of 40 patients in the metastasis group (median age: 64.5 years; 20 males) and 40 patients in the control group (median age: 64.0 years; 20 males) were evaluated. With TS CT, the overall figure of merit (FOM) of the board-certified radiologist and resident groups improved from 0.848 to 0.876 (p = 0.01) and from 0.752 to 0.799 (p = 0.02), respectively. The sub-analysis focusing on attenuation changes in lesions revealed that the FOM of osteoblastic lesions significantly improved in both the board-certified radiologist and resident groups using TS CT. The sub-analysis focusing on lesion location showed that the FOM of the resident group significantly improved in the vertebral arch (p = 0.04). CONCLUSIONS: TS CT was effective in detecting bone metastasis by both board-certified radiologists and radiology residents.


Assuntos
Neoplasias Ósseas , Aprendizado Profundo , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/secundário , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Técnica de Subtração , Tomografia Computadorizada por Raios X/métodos
12.
J Clin Neurosci ; 99: 17-21, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35228088

RESUMO

Hybrid assistive limb (HAL) is a wearable robot, which has recently been used for the treatment of patients with movement disorders including spinal cord injury (SCI). Although several studies have indicated the effectiveness of HAL for SCI patients, changes in brain activity during the HAL intervention have not yet been fully characterized. A 19-year-old man with a chronic SCI resulting in complete C4 quadriplegia underwent five weeks of HAL training for a total of ten sessions. We evaluated his brain activity using task-induced functional MRI (fMRI) after the fourth, sixth and tenth HAL sessions. We also assessed the spasticity of this patient using the modified Ashworth scale (mAs). As controls for the task-induced fMRI, we examined the brain activity in two healthy subjects. The fMRI findings indicated an increased response to a motor imagery task in the patient's cerebral cortex compared to controls. In addition, the activation pattern in his cortex changed during the five weeks of HAL intervention. We observed increased cerebral lateralization in his primary motor cortex. We also found that the laterality index calculated for the precentral gyrus had a significant negative correlation with the total mAs score over the course of the HAL treatment. Our results indicate that the cerebral cortex of the present SCI patient was hyperactive during the imagery task, and the cortical activation was reduced with progression of the HAL treatment.


Assuntos
Traumatismos da Medula Espinal , Caminhada , Adulto , Encéfalo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Quadriplegia/diagnóstico por imagem , Quadriplegia/etiologia , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/diagnóstico por imagem , Traumatismos da Medula Espinal/terapia , Caminhada/fisiologia , Adulto Jovem
13.
No Shinkei Geka ; 39(5): 485-90, 2011 May.
Artigo em Japonês | MEDLINE | ID: mdl-21512199

RESUMO

We report a case, in which quantitative 1H-MR spectroscopy (MRS) was useful for the differentiation between radiation necrosis and a recurrent tumor. The present case is a 44-year-old man who underwent the subtotal removal of a mass lesion in the left frontal lobe. The histological diagnosis was anaplastic oligodendroglioma (WHO grade III). Postoperatively, a fractionated radiotherapy (total 64Gy) and chemotherapy were performed. MRI after the radiotherapy showed no contrast enhancing lesion. MRI, 5 years after the radiotherapy, showed a growing enhancing lesion and a T1 hypointensity lesion without enhancement, both of which indicated a recurrent tumor. MR spectroscopy was performed for the differential diagnosis of these lesions. The spectrum was acquired by the point resolved spectroscopy (PRESS) method by TR/TE=2,000 ms/68 ms, 136 ms, and 272 ms and evaluated with peak pattern and quantification value of metabolite. MRS of the enhancing lesion demonstrated a decrease of the Choline-containing compounds (Cho) concentration, disappearance of N-acetylaspartate (NAA), decrease of Creatine/ Phosphocreatine (t-Cr) and presence of Lipids (Lip) and Lactate (Lac), all of which are characteristic finding of a radiation necrosis. The histological diagnosis of this lesion showed evidence also of radiation necrosis. On the other hand, MRS of the T1 hypointensity lesion without enhancement showed, a marked high peak of the Cho concentration, which is characteristic for a recurrent tumor. The histological findings of this lesion showed a diffuse proliferation of recurrent tumor cells. Quantitative 1H-MRS is a useful tool for the differentiation between radiation necrosis and recurrent tumors.


Assuntos
Encefalopatias/diagnóstico , Neoplasias Encefálicas/diagnóstico , Lobo Frontal , Espectroscopia de Ressonância Magnética , Recidiva Local de Neoplasia/diagnóstico , Oligodendroglioma/diagnóstico , Lesões por Radiação/diagnóstico , Adulto , Ácido Aspártico/análogos & derivados , Ácido Aspártico/análise , Encefalopatias/patologia , Colina/análise , Creatina/análise , Diagnóstico Diferencial , Humanos , Lactatos/análise , Lipídeos/análise , Masculino , Necrose , Oligodendroglioma/radioterapia , Fosfocreatina/análise
14.
No Shinkei Geka ; 39(11): 1091-7, 2011 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-22036822

RESUMO

We report a case of a 47-year-old male who had a left frontal lobe mass with specific magnetic resonance imaging (MRI). Four years previous to his admission to our hospital, he developed acute myelocytic leukemia and he was implanted with peripheral blood stem cell transplantation. One month before his admission, he was unable to walk due to right leg motor weakness. MRI revealed a round mass lesion at the left frontal lobe. Initial diagnosis was a brain abscess, so he was administered some antibacterial drug. However, his neurological symptoms kept getting worse with increase of mass size on MRI. T1-weighted MR images showed the mass as a low intensity lesion with incomplete ring-like Gd-enhancement. T2-weighted images showed the mass as a high intensity lesion with many linear shadows inside the mass. Diffusion weighted images showed the mass as a low intensity lesion. MR spectroscopy revealed an elevation of choline and lactate peak. Differential diagnosis was glioma or demyelinating disease. At the operation, the mass was light yellow and seen to be rich with vessels. The pathological diagnosis was xanthogranuloma in the brain. Postoperative course was uneventful. The frontal residual mass lesion decreased in size and Gd-enhancement.


Assuntos
Encefalopatias/diagnóstico , Lobo Frontal , Granuloma/diagnóstico , Imageamento por Ressonância Magnética , Abscesso Encefálico/diagnóstico , Encefalopatias/cirurgia , Neoplasias Encefálicas/diagnóstico , Doenças Desmielinizantes/diagnóstico , Diagnóstico Diferencial , Imagem de Difusão por Ressonância Magnética , Glioma/diagnóstico , Granuloma/cirurgia , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade
15.
Masui ; 60(2): 236-40, 2011 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-21384667

RESUMO

A 73-year-old patient developed convulsion and prolonged disturbance of consciousness after clipping surgery for unruptured cerebral aneurysm. The patient's consciousness improved four days after surgery, and radiological findings suggested posterior reversible encephalopathy syndrome (PRES). The cause of PRES is thought to be dysfunction of blood brain barrier by a sudden increase in blood pressure. In case of unexplained convulsion and decreased level of consciousness, PRES should be considered with radiographic examinations including CT and MRI.


Assuntos
Transtornos da Consciência/etiologia , Aneurisma Intracraniano/cirurgia , Síndrome da Leucoencefalopatia Posterior/etiologia , Complicações Pós-Operatórias/etiologia , Convulsões/etiologia , Idoso , Anestesia Geral , Anestesia Intravenosa , Feminino , Humanos , Imageamento por Ressonância Magnética , Síndrome da Leucoencefalopatia Posterior/diagnóstico , Complicações Pós-Operatórias/diagnóstico , Tomografia Computadorizada por Raios X , Procedimentos Cirúrgicos Vasculares
16.
Jpn J Radiol ; 39(8): 741-748, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33881731

RESUMO

PURPOSE: To investigate the relationship between dynamic magnetic resonance imaging (MRI) findings and hormonal activity in pituitary adenomas. METHODS: We retrospectively evaluated the dynamic MRI findings in 244 patients with pathologically confirmed pituitary adenomas and a diagnosis of clinically active prolactin (PRL)-producing adenomas. Among the 244 pituitary adenomas, 55, 16, 6, and 4 produced growth hormone (GH), PRL, adrenocorticotropic hormone, and thyroid-stimulating hormone, respectively, while 163 were non-functioning (NF) adenomas. For each adenoma, we calculated the washout rate (WR) and early (EER) and delayed (DER) tumour-to-normal-tissue enhancement ratios. RESULTS: The respective mean values of the WR, EER, and DER were 9.4%, 75.2%, and 64.5% for GH-producing adenomas; 6.2%, 117.1%, and 106.2% for PRL-producing adenomas; and 5.4%, 116.7%, and 108.7% for NF adenomas. GH-producing adenomas had significantly lower EER and DER values than PRL-producing (P < 0.001) and NF adenomas (P < 0.001). In ROC analysis of GH-producing and non-GH-producing adenomas, the areas under the curves of WR, EER, and DER were 0.593, 0.825, and 0.857, respectively. CONCLUSION: There are differences in dynamic MRI features between GH-producing and non-GH-producing adenomas, which suggests that EER and DER may be useful for diagnosing GH-producing adenomas.


Assuntos
Adenoma , Neoplasias Hipofisárias , Adenoma/diagnóstico por imagem , Adulto , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neoplasias Hipofisárias/diagnóstico por imagem , Prolactina , Estudos Retrospectivos
17.
Eur J Radiol ; 135: 109471, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33338759

RESUMO

PURPOSE: To compare deep learning with radiologists when diagnosing uterine cervical cancer on a single T2-weighted image. METHODS: This study included 418 patients (age range, 21-91 years; mean, 50.2 years) who underwent magnetic resonance imaging (MRI) between June 2013 and May 2020. We included 177 patients with pathologically confirmed cervical cancer and 241 non-cancer patients. Sagittal T2-weighted images were used for analysis. A deep learning model using convolutional neural networks (DCNN), called Xception architecture, was trained with 50 epochs using 488 images from 117 cancer patients and 509 images from 181 non-cancer patients. It was tested with 60 images for 60 cancer and 60 non-cancer patients. Three blinded experienced radiologists also interpreted these 120 images independently. Sensitivity, specificity, accuracy, and area under the receiver operating characteristic curve (AUC) were compared between the DCNN model and radiologists. RESULTS: The DCNN model and the radiologists had a sensitivity of 0.883 and 0.783-0.867, a specificity of 0.933 and 0.917-0.950, and an accuracy of 0.908 and 0.867-0.892, respectively. The DCNN model had an equal to, or better, diagnostic performance than the radiologists (AUC = 0.932, and p for accuracy = 0.272-0.62). CONCLUSION: Deep learning provided diagnostic performance equivalent to experienced radiologists when diagnosing cervical cancer on a single T2-weighted image.


Assuntos
Aprendizado Profundo , Neoplasias do Colo do Útero , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Redes Neurais de Computação , Radiologistas , Estudos Retrospectivos , Neoplasias do Colo do Útero/diagnóstico por imagem , Adulto Jovem
18.
Jpn J Radiol ; 39(2): 143-158, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32875471

RESUMO

Teratoma is a germ cell tumor (GCT) derived from stem cells of the early embryo and the germ line. Teratoma is the most common neoplasm of the ovaries and is usually diagnosed easily using imagings by detecting fat components. However, there are various histopathological types and the imaging findings differ according to the type. Teratoma usually occurs in the gonads or in the midline due to migration of primordial germ cells during development. The clinical course of teratomas depends on the age of the patient, histological type, and anatomical site. Sometimes teratomas show unusual manifestations, such as mature teratoma without demonstrable fat components, torsion, rupture, growing teratoma syndrome, anti-N-methyl-D-aspartate receptor encephalitis, and autoimmune hemolytic anemia. For all of these reasons, teratomas demonstrate a wide spectrum of imaging features and radiologists should be familiar with these variabilities. The present article aims to introduce a model encompassing types of GCTs based on their developmental potential, and to review several histopathological types in various anatomical sites and unusual manifestations of teratomas, with representative imaging findings.


Assuntos
Imageamento por Ressonância Magnética , Teratoma/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Diagnóstico por Imagem/métodos , Feminino , Humanos , Masculino , Neoplasias Embrionárias de Células Germinativas/diagnóstico por imagem , Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/patologia , Teratoma/patologia
19.
Jpn J Radiol ; 39(4): 357-366, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33216290

RESUMO

PURPOSE: To clarify imaging and clinical characteristics of ovarian carcinosarcoma (CS) compared with high-grade serous carcinoma (HGSC). METHODS: We retrospectively reviewed MR imagings of 12 patients with CS and 30 patients with HGSC and evaluated tumor size, shape, appearance, nature of cystic and solid components, hemorrhage, and necrosis. Age, premenopausal or postmenopausal, histologic subtype, presence of endometriosis, tumor markers, and stage were also evaluated. These parameters were compared using the Mann-Whitney U test and the chi-square test/Fisher's exact test. RESULTS: The mean size of CSs was 13.6 cm, and significantly larger than that of HGSCs (mean 9.0 cm, p = 0.022). The stained-glass appearance (67% vs. 23%, p = 0.013), hemorrhage (100% vs. 50%, p = 0.003), necrosis (75.0% vs. 13%, p = 0.000), and endometriosis (33% vs. 7%, p = 0.012) were significantly more common in CSs. The postmenopausal ratio of CSs was 100% and significantly higher than that of HGSCs (70.0%, p = 0.041). Among the tumor makers, only CA-125 was significantly lower in CSs than in HGSCs (mean 715.1 U/ml vs. 1677.1 U/ml, p = 0.009). The stage distribution was similar and was not significantly different. CONCLUSION: CSs formed larger masses, and the stained-glass appearance, hemorrhage, and necrosis were more frequently observed in CSs.


Assuntos
Carcinossarcoma/diagnóstico por imagem , Carcinossarcoma/patologia , Cistadenocarcinoma Seroso/diagnóstico por imagem , Cistadenocarcinoma Seroso/patologia , Imageamento por Ressonância Magnética , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/patologia , Adulto , Idoso , Biomarcadores Tumorais , Estudos de Casos e Controles , Feminino , Hemorragia/diagnóstico por imagem , Hemorragia/patologia , Humanos , Pessoa de Meia-Idade , Necrose/diagnóstico por imagem , Gradação de Tumores , Estadiamento de Neoplasias , Pós-Menopausa , Pré-Menopausa , Estudos Retrospectivos , Carga Tumoral
20.
J Neurosurg ; 110(3): 492-9, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19046044

RESUMO

OBJECT: Although conventional catheter angiography is commonly used in the evaluation of intracranial arteriovenous malformations (AVMs), less invasive tools are more suitable for screening or follow-up. Older MR angiography techniques cannot provide high enough temporal and spatial resolution for assessing AVMs. Threetesla time-resolved imaging of contrast kinetics (TRICKS)-a time-resolved, contrast-enhanced 3D MR angiography technique-achieves subsecond time resolution without sacrificing spatial resolution. The purpose of this study was to assess the accuracy of TRICKS at 3 T in the evaluation of AVMs. METHODS: Between November 2006 and November 2007, 31 patients who were known to have AVMs underwent evaluation in a 3-T unit with the TRICKS technique. The TRICKS images were then evaluated independently by 2 radiologists for nidus detection, early venous filling detection, and Spetzler-Martin classification, and these results were compared with the results of catheter angiography. RESULTS: Time-resolved imaging of contrast kinetics achieved 96% sensitivity and 100% specificity both in nidus detection and early venous filling detection. The Spetzler-Martin grades also showed excellent correlation with catheter angiography findings (kappa= 0.89). CONCLUSIONS: Although this is a preliminary study, the authors' results indicate that time-resolved contrast-enhanced 3D MR angiography at 3 T is a good tool to assess AVMs, and has the potential to replace catheter angiography in screening or follow-up examinations of patients with AVMs.


Assuntos
Malformações Arteriovenosas Intracranianas/diagnóstico , Angiografia por Ressonância Magnética/métodos , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
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