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1.
Quant Imaging Med Surg ; 12(8): 4259-4271, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35919046

RESUMO

Background: Because osteoporotic vertebral fracture (OVF) on chest radiographs is commonly missed in radiological reports, we aimed to develop a software program which offers automated detection of compressive vertebral fracture (CVF) on lateral chest radiographs, and which emphasizes CVF detection specificity with a low false positivity rate. Methods: For model training, we retrieved 3,991 spine radiograph cases and 1,979 chest radiograph cases from 16 sources, with among them in total 1,404 cases had OVF. For model testing, we retrieved 542 chest radiograph cases and 162 spine radiograph cases from four independent clinics, with among them 215 cases had OVF. All cases were female subjects, and except for 31 training data cases which were spine trauma cases, all the remaining cases were post-menopausal women. Image data included DICOM (Digital Imaging and Communications in Medicine) format, hard film scanned PNG (Portable Network Graphics) format, DICOM exported PNG format, and PACS (Picture Archiving and Communication System) downloaded resolution reduced DICOM format. OVF classification included: minimal and mild grades with <20% or ≥20-25% vertebral height loss respectively, moderate grade with ≥25-40% vertebral height loss, severe grade with ≥40%-2/3 vertebral height loss, and collapsed grade with ≥2/3 vertebral height loss. The CVF detection base model was mainly composed of convolution layers that include convolution kernels of different sizes, pooling layers, up-sampling layers, feature merging layers, and residual modules. When the model loss function could not be further decreased with additional training, the model was considered to be optimal and termed 'base-model 1.0'. A user-friendly interface was also developed, with the synthesized software termed 'Ofeye 1.0'. Results: Counting cases and with minimal and mild OVFs included, base-model 1.0 demonstrated a specificity of 97.1%, a sensitivity of 86%, and an accuracy of 93.9% for the 704 testing cases. In total, 33 OVFs in 30 cases had a false negative reading, which constituted a false negative rate of 14.0% (30/215) by counting all OVF cases. Eighteen OVFs in 15 cases had OVFs of ≥ moderate grades missed, which constituted a false negative rate of 7.0% (15/215, i.e., sensitivity 93%) if only counting cases with ≥ moderate grade OVFs missed. False positive reading was recorded in 13 vertebrae in 13 cases (one vertebra in each case), which constituted a false positivity rate of 2.7% (13/489). These vertebrae with false positivity labeling could be readily differentiated from a true OVF by a human reader. The software Ofeye 1.0 allows 'batch processing', for example, 100 radiographs can be processed in a single operation. This software can be integrated into hospital PACS, or installed in a standalone personal computer. Conclusions: A user-friendly software program was developed for CVF detection on elderly women's lateral chest radiographs. It has an overall low false positivity rate, and for moderate and severe CVFs an acceptably low false negativity rate. The integration of this software into radiological practice is expected to improve osteoporosis management for elderly women.

4.
J Oral Maxillofac Surg ; 72(11): 2366-74, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25172673

RESUMO

PURPOSE: To describe the differential diagnosis between solitary cystic metastatic carcinoma from branchial cleft cyst and provide references for clinicians to treat cystic metastases from primary sites of the head and neck region. MATERIALS AND METHODS: Two cases of cystic metastatic nasopharyngeal carcinoma (NPC) are presented and a review of the relevant English literature on cystic metastasis from head and neck cancer was performed. RESULTS: Two adult patients with a lateral cystic neck mass were initially clinically diagnosed as branchial cleft cysts. Based on the postoperative histopathologic examination and nasopharyngeal blind biopsy, they were finally diagnosed as cystic metastases from occult nasopharyngeal carcinoma. After a review of the literature, diagnostic strategies, histopathologic features, and therapeutic options for cervical cystic metastases were discussed. CONCLUSION: Cervical cystic metastasis of NPC in adults may mimic branchial cleft cyst in clinical, radiological, and even histological features. Surgeons should bear in mind that when lateral neck cysts with characteristics of suspected malignancy are confronted, nasopharynx examination, including blind or random biopsy, is highly recommended before surgery. Metastatic disease should always be considered as a potential differential diagnosis in adult patients with a cystic neck lesion. Correct diagnosis is important so that appropriate surgical and radiotherapeutic treatment can be delivered.


Assuntos
Branquioma/diagnóstico , Neoplasias Nasofaríngeas/diagnóstico , Metástase Neoplásica , Adulto , Biópsia por Agulha , Feminino , Humanos , Masculino , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/cirurgia , Tomografia Computadorizada por Raios X
5.
J Thorac Dis ; 6(7): 872-87, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25093083

RESUMO

Solitary pulmonary nodule (SPN) is defined as a rounded opacity ≤3 cm in diameter surrounded by lung parenchyma. The majority of smokers who undergo thin-section CT have SPNs, most of which are smaller than 7 mm. In the past, multiple follow-up examinations over a two-year period, including CT follow-up at 3, 6, 12, 18, and 24 months, were recommended when such nodules are detected incidentally. This policy increases radiation burden for the affected population. Nodule features such as shape, edge characteristics, cavitation, and location have not yet been found to be accurate for distinguishing benign from malignant nodules. When SPN is considered to be indeterminate in the initial exam, the risk factor of the patients should be evaluated, which includes patients' age and smoking history. The 2005 Fleischner Society guideline stated that at least 99% of all nodules 4 mm or smaller are benign; when nodule is 5-9 mm in diameter, the best strategy is surveillance. The timing of these control examinations varies according to the nodule size (4-6, or 6-8 mm) and the type of patients, specifically at low or high risk of malignancy concerned. Noncalcified nodules larger than 8 mm diameter bear a substantial risk of malignancy, additional options such as contrast material-enhanced CT, positron emission tomography (PET), percutaneous needle biopsy, and thoracoscopic resection or videoassisted thoracoscopic resection should be considered.

6.
Eur Radiol ; 24(2): 441-8, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24126641

RESUMO

OBJECTIVE: A screening survey for osteoporotic fractures in men and women in Hong Kong represents the first large-scale prospective population-based study on bone health in elderly (≥65 years) Chinese men and women. This study aims to identify the prevalence and potential risk factors of lumbar spondylolisthesis in these subjects. METHODS: The lateral lumbar radiographs of 1,994 male and 1,996 female patients were analysed using the Meyerding classification. RESULTS: Amongst the men, 380 (19.1%) had at least one spondylolisthesis and 43 (11.3%) had slips at two or more levels; 283 had anterolisthesis, 85 had retrolisthesis, whereas 12 subjects had both anterolisthesis and retrolisthesis. Amongst the women, 499 (25.0%) had at least one spondylolisthesis and 69 (13.8%) had slips at two or more levels; 459 had anterolisthesis, 34 had retrolisthesis, whereas 6 subjects had both anterolisthesis and retrolisthesis. Advanced age, short height, higher body mass index (BMI), higher bone mineral density (BMD) and degenerative arthritis are associated with spondylolisthesis. Lower Physical Activity Scale for the Elderly (PASE) score was associated with spondylolisthesis in men; higher body weight, angina and lower grip strength were associated with spondylolisthesis in women. CONCLUSION: The male/female ratio of lumbar spondylolisthesis prevalence was 1:1.3 in elderly Chinese. Men are more likely to have retrolisthesis. KEY POINTS: • The prevalence of spondylolisthesis is 19.1% in elderly Chinese men. • The prevalence of spondylolisthesis is 25.0% in elderly Chinese women. • Men are more likely to have retrolisthesis. • Anterolisthesis is most commonly seen at the L4/L5 level. • Retrolisthesis is most commonly seen at the L3/L4 level.


Assuntos
Vértebras Lombares/diagnóstico por imagem , Espondilolistese/epidemiologia , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Hong Kong/epidemiologia , Humanos , Masculino , Prevalência , Estudos Prospectivos , Radiografia , Fatores de Risco , Sexismo , Espondilolistese/diagnóstico por imagem
7.
Zhonghua Yi Xue Za Zhi ; 93(15): 1153-5, 2013 Apr 16.
Artigo em Chinês | MEDLINE | ID: mdl-23902885

RESUMO

OBJECTIVE: To perform the dynamic contrast-enhanced and perfusion magnetic resonance imaging (MRI) of nasopharyngeal carcinoma (NPC) and analyze the correlation with T-staging. METHODS: A total of 46 naïve NPC patients underwent MRI. The parameters of dynamic contrast-enhanced and perfusion MRI included time to peak (TTP), Slopemax and area under the curve (AUC). RESULTS: The increasing period of signal intensity-time curve of all cases was steep. And the perfusion image of AUC could reflect the blood perfusion of tumor tissue. Parameters (TTP/Slopemax/AUC) in different T-staging were T1-staging (60.45/10.59/20 619.56), T2-staging (58.12/12.47/23 037.23), T3-staging (70.61/15.06/26 507.23) and T4-staging (41.72/19.87/30 092.27). Their statistical results were r = -0.247, P > 0.05 and r = 0.859, P < 0.050 and r = 0.963, P < 0.05 respectively. And statistical significance existed in Slopemax, AUC with T-staging. CONCLUSION: Dynamic contrast-enhanced and perfusion MRI can reflect angiogenesis of NPC. And there is a positive correlation between the parameters of dynamic contrast-enhanced and perfusion MRI (Slopemax, AUC) and T-staging.


Assuntos
Aumento da Imagem , Angiografia por Ressonância Magnética/métodos , Neoplasias Nasofaríngeas/patologia , Adulto , Carcinoma , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Estadiamento de Neoplasias , Adulto Jovem
8.
Quant Imaging Med Surg ; 3(2): 113-20, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23630658

RESUMO

Pancreatic adenocarcinoma is the most common malignancy of the pancreas with high death rate. Preoperative imaging is crucial for the assessment of the disease and the planning of treatment. In this review, we discussed the common and unusual findings of pancreatic carcinoma. The common CT and MR findings include hypovascular mass, dilataion of upstream biliary and pancreatic ducts, invasion to adjacent structures and metastasis. The uncommon CT and MR findings include: a cystic mass, a mass without dilataion of upstream ducts, multiple masses or a lesion diffusively infiltrating most parts of the pancreas without distorting its configuration.

9.
Quant Imaging Med Surg ; 2(1): 57-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23256060

RESUMO

Gastrointestinal stromal tumors (GISTs), the most common mesenchymal tumors of the gastrointestinal tract, arise from interstitial cells of Cajal. Most of them are composed of spindle cells and mimic leiomyoma morphologically. Nearly all GISTs demonstrate positive staining for CD-117 at immunohistochemistry examination, which helps to distinguish them from true leiomyomas. We describe the CT findings of a GIST of small bowel. At plain CT scan, the tumor was of homogeneous iso-attenuation. After intravenous administration of contrast materials, a well-defined exophytic growth mass with avid homogeneous enhancement was demonstrated. The mucosal layer over the mass was intact and fat plane between the mass and adjacent GI wall was preserved. A diagnosis of GIST was suggested and was then confirmed by positive staining for CD-117.

10.
Quant Imaging Med Surg ; 2(1): 61-2, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23256062

RESUMO

Plasmacytoma can present as multiple myeloma, solitary plasmacytoma of the bone (SPB), or extramedullary plasmacytoma. SPB is a rare entity that composes of malignant plasma cells and involves the bone to form only one or two lesions without evidence of disease dissemination. It accounts for only 4% of malignant plasma cell tumors. We report a case of SPB in the skull in a 59-year-old male. CT scan revealed an 8 cm ×9 cm osteolytic lesion on the scalp of skull with a well demarcated margin. A cake-like mass was revealed at CT soft tissue window. The mass was completely excised and histological examination revealed plasmacytoma. The diagnosis of SPB was established after ruling out multiple myeloma.

11.
Quant Imaging Med Surg ; 1(1): 31-4, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23256051

RESUMO

OBJECTIVE: The aim of this study was to investigate whether adding delayed phase imaging can improve diagnostic ability of (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET) in evaluating solitary pulmonary nodules (SPNs). MATERIALS AND METHODS: 28 patients with SPNs received dual-phase (18)F-FDG PET at 1h and 2h after (18)F-FDG injection during Feb 2009 to Jun 2011were included in this retrospective study. Their final diagnosis was confirmed by pathological examination in 27 cases and clinical follow-up in 1 case. The standardized uptake value (SUV) of early and delayed phases of all lesions was measured. RESULTS: The 28 SPNs included 9 benign lesions and 19 malignant lesions. Using SUV ≥2.5 as a criteria for malignancy, the sensitivity, specificity, and accuracy were 52.6%, 55.6% and 53.6% respectively at early phase; 68.4%, 55.6% and 64.3% respectively at early and delayed phases combined. Combined early and delayed phase scans combined picked up 3 additional malignant lesions from the 14 lesions with an initial SUV value less than 2.5, and there was no additional false positive result with the benign lesions. CONCLUSION: Adding delayed phase scanning resulted in correct diagnosis of three malignant lesions with an initial SUV value less than 2.5. Delayed phase scanning can be recommended in the SPNs with SUV less than 2.5 at early phase.

13.
Clin Imaging ; 32(3): 172-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18502343

RESUMO

Gastrointestinal stromal tumors (GISTs) are the most common gastrointestinal mesenchymal tumors. Computed tomography (CT) often shows exophytic gastrointestinal masses with cystic changes, necrosis or fistula formation, and heterogeneous enhancement. After Gleevec therapy, the primary tumor, its metastases, and its recurrences can develop cystic changes and decrease in size, these findings can be satisfactorily monitored by CT. We report on 42 patients with proven GISTs, five presenting with metastases and nine patients with recurrence or development of metastases after surgery and chemotherapy.


Assuntos
Neoplasias Gastrointestinais/diagnóstico por imagem , Tumores do Estroma Gastrointestinal/diagnóstico por imagem , Recidiva Local de Neoplasia/diagnóstico por imagem , Intensificação de Imagem Radiográfica , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biópsia por Agulha , Terapia Combinada , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Neoplasias Duodenais/diagnóstico por imagem , Neoplasias Duodenais/patologia , Neoplasias Duodenais/terapia , Estudos de Avaliação como Assunto , Feminino , Seguimentos , Neoplasias Gastrointestinais/patologia , Neoplasias Gastrointestinais/terapia , Tumores do Estroma Gastrointestinal/patologia , Tumores do Estroma Gastrointestinal/terapia , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/terapia , Estadiamento de Neoplasias , Neoplasias Peritoneais/diagnóstico por imagem , Neoplasias Peritoneais/patologia , Neoplasias Peritoneais/terapia , Estudos Retrospectivos , Sensibilidade e Especificidade , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/patologia , Neoplasias Gástricas/terapia , Resultado do Tratamento
15.
Chin J Traumatol ; 7(5): 289-93, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15363223

RESUMO

OBJECTIVE: To investigate the diagnostic value of multidetector spiral CT (MSCT) in acute thoracolumbar spinal fracture and fracture-dislocation. METHODS: CT imaging files of 152 consecutive traumatic patients with thoracolumbar fractures were retrospectively reviewed. MSCT scannings were performed with a collimation of 3-5 mm and a pitch of 5.5. The postprocessing included sagittal and coronal multiplannar reconstruction, and 3-D reconstruction. RESULTS: There were 88 cases of compression fracture, 54 cases of burst fracture and 10 cases of fracture-dislocation. Transverse images of MSCT could visualize all fractures directly and determine whether spinal canal was intact. Postprocessing image was helpful in depicting the displacement of fragment and orientation of dislocation. CONCLUSIONS: MSCT plays an important role in diagnosis and management of acute thoracolumbar spinal fracture and fracture-dislocation.


Assuntos
Processamento de Imagem Assistida por Computador , Fraturas da Coluna Vertebral/diagnóstico por imagem , Tomografia Computadorizada Espiral , Adulto , Idoso , Estudos de Coortes , Feminino , Seguimentos , Fixação de Fratura/métodos , Consolidação da Fratura/fisiologia , Humanos , Escala de Gravidade do Ferimento , Vértebras Lombares/lesões , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Sensibilidade e Especificidade , Fraturas da Coluna Vertebral/cirurgia , Vértebras Torácicas/lesões , Resultado do Tratamento
16.
World J Gastroenterol ; 10(13): 1943-7, 2004 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15222042

RESUMO

AIM: To investigate the role of curved planar reformations using multidetector spiral CT (MSCT) in diagnosis of pancreatic and peripancreatic diseases. METHODS: From October 2001 to September 2003, 47 consecutive patients with pancreatic or peripancreatic diseases, which were confirmed by operation, endoscopic retrograde cholangiopancreatography and clinical follow-up, were enrolled in this study. CT scanning was performed at a MSCT with four rows of detector. A set of images with an effective thickness of 1.0-2.0 mm and a gap of 0.5-1.0 mm (50% overlap) were acquired in all patients for post-processing. Curved planar reformations were carried out by drawing a curved line on transverse source images, coronal or sagittal multiplanar reformations according to certain anatomic structures (such as cholangiopancreatic ducts or peripancreatic vessels) and the position of lesion. RESULTS: With thin collimation, MSCT could acquire high-quality curved planar reformations to display the profile of the whole pancreas, to trace the cholangiopancreatic ducts and peripancreatic vessels, and to show the relationship of lesions with pancreas and peripancreatic anatomic structures in one curved plane, which facilitates diagnosis and rapid communication of diagnostic information with referring physicians. CONCLUSION: MSCT with thin collimation could be used to create high-quality curved planar reformations in evaluating pancreatic and peripancreatic diseases with pertinent anatomic information and relative pathologic signs to facilitate the diagnosis and enhance communication with the referring physician. Curved planar reformations can serve as supplements for transverse images in diagnosis and management of pancreatic and peripancreatic diseases.


Assuntos
Carcinoma Neuroendócrino/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico por imagem , Pseudocisto Pancreático/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Idoso , Ampola Hepatopancreática/diagnóstico por imagem , Colangiopancreatografia Retrógrada Endoscópica , Feminino , Humanos , Masculino , Artérias Mesentéricas/diagnóstico por imagem , Pessoa de Meia-Idade , Pâncreas/diagnóstico por imagem , Artéria Esplênica/diagnóstico por imagem
17.
Hepatobiliary Pancreat Dis Int ; 1(3): 420-4, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-14607719

RESUMO

OBJECTIVES: To study prospectively the enhancement features of small hepatocellular carcinoma (SHCC) with multi-phase scanning of dynamic MRI and spiral CT, and discuss the superiority of dynamic MRI to spiral CT. METHODS: Multi-phase dynamic contrast scanning of high field MRI and spiral CT were performed in 53 patients with SHCC. The arterial phase, portal venous phase and delayed phase scanning of spiral CT was done after the pre-contrast scanning of the entire liver. MRI was performed with SE sequence and fast multiplanar spoiled gradient-recalled sequence dynamic multi-phase contrast scanning. RESULTS: Seventy-six lesions were found in all 53 patients. Sixty-nine and 54 of the 76 lesions enhanced obviously in MRI and spiral CT arterial phase scanning respectively. The typical enhancement patterns of SHCC in the arterial phase, portal venous phase and delayed phase scanning of MRI and spiral CT were hyper-hypo-hypointense (dense) and hyper-iso-hypointense (dense). Atypical enhancement patterns were hyper-hyper-hyperintense (dense), hyper-iso-isointense (dense) and hypo-hypo-hypointense (dense). CONCLUSIONS: Both MRI and spiral CT multi-phase dynamic contrast-enhanced scanning could demonstrate the enhancement features of SHCC, and arterial phase scan of MRI was superior to spiral CT in reflecting the hypervascular characterization of SHCC. In addition, MRI was better than spiral CT in characterization of hepatic lesions combined with SE sequence.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Aumento da Imagem , Neoplasias Hepáticas/diagnóstico , Imageamento por Ressonância Magnética , Tomografia Computadorizada Espiral , Adulto , Idoso , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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