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1.
Medicine (Baltimore) ; 99(2): e18069, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31914012

RESUMO

This study aims to find and locate foramens exactly in maxilla and mandible in case of complications during surgeries.Computer topographic angiography (CTA) images of 120 cases were reviewed. The measurements were performed on coronal, sagittal and axial planes after the 3 dimension volume reconstruction. The distances among foramens, bony landmarks, teeth, and facial artery were all measured with the angles as adjustments.The incisive foramen (IF) was measured 20.55 ±â€Š2.81 mm to margo inferior of incisor, and 45.27 ±â€Š5.27 degree from the axial midline. The greater palatine foramen located 43.17 ±â€Š2.55 mm from the IF, while 21.08 ±â€Š3.75 degree from the midline in axial plane. The lesser palatine foramina located 44.56 ±â€Š5.74 mm from the IF and 20.05 ±â€Š3.59 degree to the midline. The Mandibular foramen (MBF) was 91.15 ±â€Š1.86 mm horizontally to the margo inferior of incisor. The angle that the MBF-margo inferior of incisor line made with the axial midline was 31.25 ±â€Š2.89 degree. The shortest horizontal distance from the mental foramen (MF) to the facial artery in sagittal plane was 21.90 ±â€Š1.86 mm, while it became 13.00 ±â€Š2.05 mm in coronary section. The horizontal distance from the MF to the margo inferior of incisor in sagittal plane was 22.04 ±â€Š3.22 mm. It turned out to be 25.78 ±â€Š5.23 mm between MF and mid-sagittal line in coronary section. The vertical distance was 25.20 ±â€Š3.06 mm from the upper margin of the second premolar to the MF.The foramens were clearly seen through CTA. Moreover, linear and angular measurements were presented, which makes it safer and wiser for surgeons to consider the biometric data before operations.


Assuntos
Pontos de Referência Anatômicos/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Mandíbula/anatomia & histologia , /diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Artérias , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/cirurgia , Criança , Face/irrigação sanguínea , Face/diagnóstico por imagem , Feminino , Humanos , Incisivo/anatomia & histologia , Incisivo/diagnóstico por imagem , Masculino , Mandíbula/diagnóstico por imagem , Mandíbula/patologia , Mandíbula/cirurgia , Pessoa de Meia-Idade , Adulto Jovem
2.
Radiol Med ; 125(1): 48-56, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31522345

RESUMO

PURPOSE: Development of a fully automatic algorithm for the automatic localization and identification of vertebral bodies in computed tomography (CT). MATERIALS AND METHODS: This algorithm was developed using a dataset based on real-world data of 232 thoraco-abdominopelvic CT scans retrospectively collected. In order to achieve an accurate solution, a two-stage automated method was developed: decision forests for a rough prediction of vertebral bodies position, and morphological image processing techniques to refine the previous detection by locating the position of the spinal canal. RESULTS: The mean distance error between the predicted vertebrae centroid position and truth was 13.7 mm. The identification rate was 79.6% on the thoracic region and of 74.8% on the lumbar segment. CONCLUSION: The algorithm provides a new method to detect and identify vertebral bodies from arbitrary field-of-view body CT scans.


Assuntos
Algoritmos , Árvores de Decisões , Aprendizado de Máquina , Tomografia Computadorizada Multidetectores/métodos , Coluna Vertebral/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Pontos de Referência Anatômicos/diagnóstico por imagem , Conjuntos de Dados como Assunto , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
3.
Int J Radiat Oncol Biol Phys ; 106(3): 630-638, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31759076

RESUMO

PURPOSE: Intensity modulated proton therapy (IMPT) of locally advanced prostate cancer can spare the bowel considerably compared with modern photon therapy, but simultaneous treatment of the prostate (p), seminal vesicles (sv), and lymph nodes is challenging owing to day-to-day organ motion and range uncertainties. Our purpose was, therefore, to generate a plan library for use in adaptive IMPT to mitigate these uncertainties. METHODS AND MATERIALS: We retrospectively included 27 patients with a series of computed tomography scans throughout their treatment representing day-to-day variation. In 18 of the patients, target motion was analyzed using rigid shifts of prostate gold markers relative to bony anatomy. A plan library with different p and sv planning target volume (p/sv-PTV) positions was defined from the distribution and direction of these shifts. Delivery of IMPT using plan selection from the library was simulated for image guidance on bony anatomy, in the remaining patients and compared with nonadaptive IMPT. RESULTS: The plan library consisted of 3 small margin p/sv-PTVs: (1) p/sv-PTV shifted 1.5 systematic error (Σ) of the population mean in the anterior and cranial directions, (2) p/sv-PTV shifted 1.5Σ in the posterior and caudal directions, and (3) p/sv-PTV in the planning position. The conventional p/sv-PTV was also available for backup. Plan selection compared with nonadaptive IMPT resulted in a reduction of the rectum volume receiving 60 Gy relative biological effect (RBE) (V60GyRBE) from on average 12 mL to 9 mL. For the bladder the average V45GyRBE was reduced from 36% to 30%. Large and small bowel doses were also reduced, whereas target coverage was comparable or improved compared with nonadaptive IMPT. CONCLUSIONS: Plan selection based on a population model of rigid target motion was feasible for all patients. Compared with conventional IMPT, plan selection resulted in significant dosimetric sparing of rectum and bladder without compromising target coverage.


Assuntos
Movimentos dos Órgãos , Neoplasias da Próstata/radioterapia , Terapia com Prótons/métodos , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada/métodos , Pontos de Referência Anatômicos/diagnóstico por imagem , Marcadores Fiduciais , Ouro , Humanos , Bibliotecas Digitais , Linfonodos/diagnóstico por imagem , Irradiação Linfática/métodos , Masculino , Tratamentos com Preservação do Órgão/métodos , Órgãos em Risco/diagnóstico por imagem , Próstata/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/métodos , Reto/diagnóstico por imagem , Estudos Retrospectivos , Glândulas Seminais/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Incerteza , Bexiga Urinária/diagnóstico por imagem
4.
Chiropr Man Therap ; 27: 47, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31660122

RESUMO

Background: To determine whether a discrepancy exists in identifying three musculoskeletal landmarks (medial meniscus, lateral malleolus and lateral epicondyle of the humerus) and whether ultrasound-guided (US-guided) palpation intervention can reduce that discrepancy and improve localization for chiropractic interns. Methods: Sixteen chiropractic interns were asked to identify three subcutaneous anatomical landmarks before/ after the intervention and at a 3-day follow-up. The intervention was a three-minute US-guided demonstration of the landmarks after the intern's initial localization. The primary outcome measure was the change in distance between the intern's landmark identification. Non-normal data were analyzed with the Friedman's and Wilcoxon signed rank tests. Discrepancy between examiner-determined landmarks and intern-identified landmarks at the initial time point was assessed with a 1-sample Wilcoxon signed rank test. Results: All locations demonstrated an initial discrepancy between examiner-determined landmarks and intern-identified landmarks at the initial time point. Overall, a statistically significant difference was noted in the identification of the medial meniscus (p = 0.012) and lateral malleolus (p = 0.001), but not at the lateral epicondyle (p = 0.086). For the before and immediately after comparison, a significant improvement was found with the medial meniscus (p = 0.005) and lateral malleolus (p = 0.002). The 3-day post-intervention comparison found an improvement only for the lateral malleolus (p = 0.008). Conclusion: This pilot study demonstrated palpatory discrepancy at identifying all three landmarks. Our data suggests that US-guided palpation intervention seems to improve an intern's ability to palpate two landmarks (medial meniscus and lateral malleolus) post-intervention.


Assuntos
Pontos de Referência Anatômicos/diagnóstico por imagem , Quiroprática/educação , Adulto , Feminino , Humanos , Úmero/diagnóstico por imagem , Internato e Residência , Masculino , Meniscos Tibiais/diagnóstico por imagem , Palpação , Projetos Piloto , Estudantes , Ultrassonografia , Adulto Jovem
5.
Br J Radiol ; 92(1104): 20190221, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31596118

RESUMO

OBJECTIVE: Early detection of tibialis posterior tendon changes and appropriate intervention is necessary to prevent disease progression to flat-foot deformity and foot/ankle dysfunction, and the need for operative treatment. Currently, differentiating between early-stage tibialis posterior tendon deficiency patients who will benefit from conservative vs more aggressive treatment is challenging. The objective of this work was to establish a quantitative MRI T2* mapping method and subregion baseline values in the tibialis posterior tendon in asymptomatic ankles for future clinical application in detecting tendon degeneration. METHODS: 26 asymptomatic volunteers underwent T2* mapping. The tendon was divided axially into seven subregions. Summary statistics for T2* within each subregion were calculated and compared using Tukey post-hoc pairwise comparisons. RESULTS: Results are reported for 24 subjects. The mean tibialis posterior tendon T2* was 7 ± 1 ms. Subregion values ranged from 6 ± 1 to 9 ± 2 ms with significant between-region differences in T2*. Inter- and intrarater absolute agreement intraclass correlation coefficient (ICC) values were all "excellent" (0.75 < ICC=1.00) except for regions 5 through 7, which had "fair to good" interrater and/or and intrarater ICC values (0.4 < ICC=0.75). CONCLUSION: A tibialis posterior tendon T2* mapping protocol, subregion division method, and baseline T2* values for clinically relevant regions were established. Significant differences in T2* were observed along the tendon length. ADVANCES IN KNOWLEDGE: This work demonstrates that regional variation exists and should be considered for future T2*-based research on posterior tibias tendon degeneration and when using T2* mapping to evaluate for potential tibialis posterior tendon degeneration.


Assuntos
Pontos de Referência Anatômicos/diagnóstico por imagem , Perna (Membro)/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Tendões/diagnóstico por imagem , Adulto , Pontos de Referência Anatômicos/anatomia & histologia , Doenças Assintomáticas , Feminino , Humanos , Perna (Membro)/anatomia & histologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Ossos do Tarso/anatomia & histologia , Ossos do Tarso/diagnóstico por imagem , Tendinopatia/diagnóstico por imagem , Tendinopatia/patologia , Tendões/anatomia & histologia , Adulto Jovem
6.
Int J Radiat Oncol Biol Phys ; 105(5): 1151-1159, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31476419

RESUMO

PURPOSE: To evaluate the feasibility of fiducial markers as a surrogate for gross tumor volume (GTV) position in image-guided radiation therapy of rectal cancer. METHODS AND MATERIALS: We analyzed 35 fiducials in 19 patients with rectal cancer who received short-course radiation therapy or long-course chemoradiation therapy. Magnetic resonance imaging examinations were performed before and after the first week of radiation therapy, and daily pre- and postirradiation cone beam computed tomography scans were acquired in the first week of radiation therapy. Between the 2 magnetic resonance imaging examinations, the fiducial displacement relative to the center of gravity of the GTV (COGGTV) and the COGGTV displacement relative to bony anatomy were determined. Using the cone beam computed tomography scans, inter- and intrafraction fiducial displacement relative to bony anatomy were determined. RESULTS: The systematic error of the fiducial displacement relative to the COGGTV was 2.8, 2.4, and 4.2 mm in the left-right, anterior-posterior (AP), and craniocaudal (CC) directions, respectively. Large interfraction systematic errors of up to 8.0 mm and random errors up to 4.7 mm were found for COGGTV and fiducial displacements relative to bony anatomy, mostly in the AP and CC directions. For tumors located in the mid and upper rectum, these errors were up to 9.4 mm (systematic) and 5.6 mm (random) compared with 4.9 mm and 2.9 mm for tumors in the lower rectum. Systematic and random errors of the intrafraction fiducial displacement relative to bony anatomy were ≤2.1 mm in all directions. CONCLUSIONS: Large interfraction errors of the COGGTV and the fiducials relative to bony anatomy were found. Therefore, despite the observed fiducial displacement relative to the COGGTV, the use of fiducials as a surrogate for GTV position reduces the required margins in the AP and CC directions for a GTV boost using image-guided radiation therapy of rectal cancer. This reduction in margin may be larger in patients with tumors located in the mid and upper rectum compared with the lower rectum.


Assuntos
Marcadores Fiduciais , Ouro , Radioterapia Guiada por Imagem/instrumentação , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/radioterapia , Carga Tumoral , Idoso , Idoso de 80 Anos ou mais , Pontos de Referência Anatômicos/diagnóstico por imagem , Quimiorradioterapia , Tomografia Computadorizada de Feixe Cônico/estatística & dados numéricos , Fracionamento da Dose de Radiação , Estudos de Viabilidade , Feminino , Humanos , Ísquio/diagnóstico por imagem , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Movimentos dos Órgãos , Sínfise Pubiana/diagnóstico por imagem , Erros de Configuração em Radioterapia , Radioterapia Guiada por Imagem/métodos , Neoplasias Retais/patologia , Fatores de Tempo
7.
Am J Orthod Dentofacial Orthop ; 156(3): 337-344, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31474263

RESUMO

INTRODUCTION: Clinical evaluation of the midface including the paranasal and upper lip regions is highly subjective and complex. Traditional and 3-dimensional cephalometrics were not developed with the clinical appearance of these midfacial areas in mind and are therefore inappropriate surrogates for the clinical appearance of the midface, making them unsuitable as aids in diagnosing dentofacial deformities. The aim of this study was to evaluate traditional as well as newly defined landmarks and measurements and their correlation with clinical appearance of the midface. METHODS: Fifty-two subjects who underwent full-field cone-beam computed tomography were recruited for this study. A single examiner assessed each subject's midfacial region (paranasal and upper lip), and a second examiner obtained traditional and newly defined cephalometric measurements for each subject. Both examiners were blinded to each other's data throughout the study. Statistical analysis was performed to assess the correlations of the traditional and novel cephalometric measurements with clinical midfacial findings. The impact of the soft tissue thickness in the paranasal region was also analyzed. The performance of any classification derived from statistically significant variables was analyzed with the use of micro-F scores and area under the receiver operating characteristic curve (AUC). RESULTS: Both traditional (SNA) and newly defined measurements (SNANS, SNPR, SNNP, SNh) had no statistically significant correlation with clinical paranasal diagnosis. However, in the absence of upper lip procumbency or protrusion, SNNP and SNh had statistically significant correlations with clinical paranasal diagnosis (P = 0.047 and P = 0.003, respectively). For upper lip analysis, both traditional (SNA) and newly defined measurements (SNCEJ) had strong correlations with clinical upper lip diagnosis (P < 0.001). All statistically significant cephalometric variables had good intra- and interobserver reliability (correlation coefficients ≥0.972 and ≥ 0.968, respectively) except SNA, which had a low interobserver reliability (correlation coefficient 0.739). Fitted models for paranasal and upper lip analyses showed low micro-F scores, indicating low precision and recall. However, AUC values of 0.7019 and 0.6362 for the paranasal and upper lip analysis, respectively, suggest improved performance of the model when properly trained with a larger sample size. CONCLUSIONS: Newly defined measurements SNh and SNNP correlated with clinical paranasal diagnosis only in the absence of upper lip procumbency and protrusion. SNA and SNCEJ were strongly correlated with clinical upper lip diagnosis. However, fitted models based on this study sample yielded low micro-F scores, making the fitted models currently unsuitable for anything besides correlation with clinical findings. A larger sample size will be necessary to further clarify the potential roles of these measurements, especially given the reasonable AUC values. The findings of this study demonstrate the highly subjective and relative nature of midfacial diagnosis and the importance of clinical judgment despite the potential utility of some traditional and new measurements.


Assuntos
Pontos de Referência Anatômicos/anatomia & histologia , Pontos de Referência Anatômicos/diagnóstico por imagem , Cefalometria/métodos , Imagem Tridimensional/métodos , Maxila/anatomia & histologia , Maxila/diagnóstico por imagem , Adolescente , Adulto , Criança , Tomografia Computadorizada de Feixe Cônico/métodos , Face/anatomia & histologia , Face/diagnóstico por imagem , Feminino , Humanos , Imagem Tridimensional/estatística & dados numéricos , Lábio/anatomia & histologia , Lábio/diagnóstico por imagem , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Adulto Jovem
8.
Medicine (Baltimore) ; 98(27): e16388, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31277196

RESUMO

Tuffier line is a common landmark for spinal anesthesia. The 10th rib line has been suggested as a new landmark to predict the intervertebral levels. We evaluated the accuracy of these 2 anatomic landmarks for identifying the L4-L5 intervertebral space using ultrasonography in elderly patients with hip fracture.Seventy-nine elderly patients scheduled for hip fracture surgery under spinal anesthesia were included. In the lateral decubitus position with the fracture side up, the L4-L5 intervertebral space was identified alternately using Tuffier line, a line drawn between the highest points of both iliac crests, and the 10th rib line. The 10th rib line, an imaginary line that joints the 2 lowest points of the rib cage, passes through the L1-L2 intervertebral space or the body of L2. The L4-L5 intervertebral space was determined by the counting-down method from the 10th rib line. Then, the estimated intervertebral spaces were evaluated using ultrasonography.The L4-L5 intervertebral space was correctly identified in 47 (59%) patients with Tuffier line and 45 (57%) patients with the 10th rib line (P = .87). The estimation ratio related to the intervertebral levels was not different between the 2 landmarks (P = .40). The wrong identifications of intervertebral level with Tuffier line and the 10th rib line was observed in the following order: L3-L4 intervertebral space: 27% vs 24%, L5-S1 intervertebral space: 9% vs 16%, and L2-L3 intervertebral space: 5% vs 3%, respectively.Tuffier line and the 10th rib line may be unreliable to estimate the intervertebral space for spinal anesthesia in elderly patients with hip fracture.


Assuntos
Pontos de Referência Anatômicos/diagnóstico por imagem , Raquianestesia , Fraturas do Quadril/cirurgia , Vértebras Lombares/diagnóstico por imagem , Costelas/diagnóstico por imagem , Ultrassonografia , Idoso , Idoso de 80 Anos ou mais , Feminino , Fraturas do Quadril/diagnóstico por imagem , Humanos , Masculino , Estudos Prospectivos , Reprodutibilidade dos Testes
9.
Int J Radiat Oncol Biol Phys ; 105(3): 649-658, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31260718

RESUMO

PURPOSE: Lymphedema after regional nodal irradiation is a severe complication that could be minimized without significantly compromising nodal coverage if the anatomic region(s) associated with lymphedema were better defined. This study sought to correlate dose-volume relationships within subregions of the axilla with lymphedema outcomes to generate treatment planning guidelines for reducing lymphedema risk. METHODS AND MATERIALS: Women with stage II-III breast cancer who underwent breast surgery with axillary assessment and regional nodal irradiation were identified. Nodal targets were prospectively contoured per Radiation Therapy Oncology Group guidelines for field design. The axilla was divided into 8 distinct subregions that were retrospectively contoured. Lymphedema outcomes were assessed by arm circumferences. Multivariate Cox proportional hazards regression assessed patient, surgical, and dosimetric predictors of lymphedema outcomes. RESULTS: Treatment planning computed tomography scans for 265 women treated between 2013 and 2017 were identified. Median post-radiation therapy follow-up was 3 years (interquartile range [IQR], 1.9-3.6). Dose to the axillary-lateral thoracic vessel juncture (ALTJ; superior to level I) was most associated with lymphedema risk (maximally selected rank statistic = 6.3, P < .001). The optimal metric was ALTJ minimum dose (Dmin) <38.6 Gy (3-year lymphedema rate 5.7% vs 37.4%, P <.001), although multiple parameters relating to sparing of the ALTJ were highly correlated. Multivariate analysis confirmed ALTJ Dmin <38.6 Gy (hazard ratio [HR], 0.13; P < .001), body mass index (HR, 1.06/unit; P = .002), and number of lymph nodes removed (HR, 1.08/node; P < .001) as significant predictors. Women with ALTJ Dmin <38.6 Gy maintained median V45Gy of 99% in the supraclavicular (IQR, 94-100%), 100% in level III (IQR, 97%-100%), 98% in level II (IQR, 86%-100%), and 91% in level I (IQR, 75%-98%) nodal basins. CONCLUSIONS: Anatomic studies suggest the ALTJ region is typically traversed by arm lymphatics and appears to be an organ at risk in breast radiation therapy. Ideally, avoidance of the ALTJ may be feasible while simultaneously encompassing breast-draining nodal basins. Confirmation of this finding in future prospective studies is needed.


Assuntos
Neoplasias da Mama/radioterapia , Linfonodos/efeitos da radiação , Irradiação Linfática/efeitos adversos , Linfedema/etiologia , Órgãos em Risco , Planejamento da Radioterapia Assistida por Computador , Adulto , Pontos de Referência Anatômicos/diagnóstico por imagem , Axila , Neoplasias da Mama/patologia , Feminino , Humanos , Excisão de Linfonodo/estatística & dados numéricos , Linfonodos/diagnóstico por imagem , Linfedema/prevenção & controle , Pessoa de Meia-Idade , Análise Multivariada , Modelos de Riscos Proporcionais , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/estatística & dados numéricos
10.
Surg Radiol Anat ; 41(8): 927-934, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31069446

RESUMO

PURPOSE: To investigate the prevalence, location, and morphology of the mandibular lingual foramen (MLF), mandibular incisive canal (MIC), and anterior loop of the inferior alveolar canal (ALC) in a Chinese population using cone-beam CT (CBCT). MATERIALS AND METHODS: From 2014 to 2016, CBCT images from patients with various scanning purposes were obtained from the database of the Affiliated Stomatology Hospital of Kunming Medical University, China. Imaging analyses of the MLF, MIC, and ALC were performed via the NNT viewer software. The prevalence, location, length, classification of MLF, and its distances to the alveolar crest and the lower border of mandible were investigated, and the prevalence and length of MIC and the prevalence of ALC were also studied. RESULTS: This study examined 1008 subjects, 521 (51.7%) males, and 487 (48.3%) females. 916 (90.9%) subjects showed the medial lingual foramina (LF), a single medial LF with the supraspinous-type predominating. Lateral LF were observed in 547 (54.3%) subjects mostly located in the premolar areas. 876 (86.9%) subjects had the MIC on the left side, whereas 877 (87.0%) had the MIC on the right side. The ALC was present in 147 (14.6%) subjects. CONCLUSIONS: This study showed a high prevalence of LF and MIC in the Southwest Chinese population. Therefore, caution should be taken during the implant treatment at the anterior mandible region.


Assuntos
Processo Alveolar/anatomia & histologia , Pontos de Referência Anatômicos/anatomia & histologia , Variação Anatômica , Mandíbula/anatomia & histologia , Adulto , Processo Alveolar/diagnóstico por imagem , Processo Alveolar/cirurgia , Pontos de Referência Anatômicos/diagnóstico por imagem , China , Tomografia Computadorizada de Feixe Cônico , Implantação Dentária Endo-Óssea/efeitos adversos , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Complicações Intraoperatórias/etiologia , Complicações Intraoperatórias/prevenção & controle , Masculino , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle
11.
Cancer Imaging ; 19(1): 20, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30935419

RESUMO

BACKGROUND: Post-hysterectomy histopathological examination is currently the main diagnostic tool for differentiating uterine sarcomas from leiomyomas. This study aimed to investigate the diagnostic accuracy of preoperative quantitative metrics based on T2-weighted sequences and contrast-enhanced MRI (CE-MRI) for distinguishing uterine sarcomas from leiomyomas. MATERIALS AND METHODS: The institutional review board approved the study. Sixty-five women confirmed to have a total of 105 lesions participated. Routine pelvic MRI sequences, T2 map and CE-MRI images were performed preoperatively using a 3 T MR scanner. Six quantitative metrics-T2 mapping parameter, T2 scaled ratio, tumor myometrium contrast ratio on T2, tumor psoas contrast ratio on T2, tumor myometrium contrast-enhanced ratio, and tumor psoas contrast-enhanced ratio-were extracted from the acquired image sets. Chi-square test was used to compare the percentage of malignant lesions with the central necrosis to the corresponding percentage for the benign masses. Using the area under receiver operating characteristic (AUC) curve, the performance of different metrics for distinguishing uterine sarcomas from leiomyomas was measured. Moreover, for each metric, we extracted the optimal cut-off value. The values of sensitivity, specificity, negative predictive value, and positive predictive value were calculted for the classifiers based on different metrics. RESULTS: The average age, average lesion size, and proportion of premenopausal women in benign and malignant groups were comparable in our dataset. The signal intensity of uterine sarcomas at T2-weighted sequences was significantly higher than that of leiomyomas (p < 0.001), while intensity at T1-weighted sequences exhibited no significant difference between the two masses (p = 0.201). Our data also suggested that a central necrosis was ten times more common among malignant lesions compared to benign ones (p < 0.001). Among different metrics, T2 mapping parameter achieved the highest AUC value and accuracy in differentiating two groups. Three measures-T2 scaled ratio, tumor myometrium contrast ratio on T2, and tumor myometrium contrast-enhanced ratio-achieved a sensitivity of 100%, therefore none of the malignant lesions would have been missed if these metrics had been adopted in patient management. CONCLUSIONS: The findings suggested that the evaluated metrics could be useful in the preoperative assessment of myometrial masses to differentiate uterine sarcomas from leiomyomas. The proposed framework has major implications for improving current practice in the management of myometrial masses.


Assuntos
Meios de Contraste , Leiomioma/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Miométrio/diagnóstico por imagem , Músculos Psoas/diagnóstico por imagem , Sarcoma/diagnóstico por imagem , Neoplasias Uterinas/diagnóstico por imagem , Adulto , Idoso , Pontos de Referência Anatômicos/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Curva ROC , Sensibilidade e Especificidade
12.
J Craniofac Surg ; 30(3): 863-867, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30817530

RESUMO

This is a retrospective analytical cross-sectional study involving 131 cone-beam computed tomography (CBCT) scans of adult (18-99 years) that assessed greater palatine canal (GPC) attributes (length, curvature angle, diameter of curvature) and the type of the trajectory of GPC-pterygopalatine fossa (PPF) component. The GPC is an important landmark that connects the oral cavity and PPF. It contains greater and lesser palatine nerves, along-with descending palatine artery and vein by extending from the inferior part of the PPF to the hard palate. The GPC acts as a pathway for infiltration of local anesthesia. The inferior orbital fissure (IOF) is in close proximity to these vital anatomic structures and hence accurate identification of its location during regional block anesthesia is crucial. This is one of the very few studies investigating these important structures on CBCT scans highlighting the importance of preoperative scans for the anatomic determination. The images were analyzed for the lengths and anatomic paths of the right and left GPC-PPF in sagittal plane. The diameters of the upper (higher bony aspect of PPF) and lower openings (GPC opening) displayed statistically significant differences in the comparison between males and females (P < 0.05). Overestimation or underestimation of the GPC length can cause a lack of anesthesia and undesirable diffusion of the anesthetic solution into the orbit thorough the IOF causing diplopia, or into the cranial cavity. A thorough understanding of GPC length and pathway types is obligatory for proper anesthetic administration and performing any maxillofacial procedures.


Assuntos
Boca/anatomia & histologia , Órbita/anatomia & histologia , Fossa Pterigopalatina/anatomia & histologia , Fossa Pterigopalatina/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Pontos de Referência Anatômicos/diagnóstico por imagem , Anestesia Local , Tomografia Computadorizada de Feixe Cônico , Estudos Transversais , Feminino , Humanos , Masculino , Maxila , Pessoa de Meia-Idade , Boca/diagnóstico por imagem , Órbita/diagnóstico por imagem , Estudos Retrospectivos , Adulto Jovem
13.
J Craniomaxillofac Surg ; 47(2): 311-319, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30598396

RESUMO

PURPOSE: To evaluate the effects of surgical navigation in zygomaticomaxillary complex (ZMC) fracture reduction. ZMC symmetry was assessed quantitatively. MATERIALS AND METHODS: The sample comprised 25 patients who underwent surgical reduction of comminuted ZMC fractures. They were divided into two groups according to the use of surgical navigation. Reduction outcomes were evaluated using three-dimensional computed tomography models. Five pairs of landmarks were identified on all craniofacial models, and asymmetry scores were calculated based on their coordinates. In quantitative analyses, symmetry and orbital volume were compared between groups. RESULTS: All patients recovered uneventfully. Greater symmetry was observed in the navigation group than in the control group for three of the five pairs of landmarks (p < 0.05). Although postoperative volumes of the injured orbits were similar between the two groups (p > 0.05), reduced orbital volumes were larger in the navigation group, indicating better restoration of the fractured orbits (p < 0.05). CONCLUSIONS: The use of surgical navigation can increase postoperative symmetry of the bilateral ZMC. The quantitative evaluation of clinical outcomes is precise and highly reliable.


Assuntos
Fixação de Fratura/métodos , Fraturas Maxilares/cirurgia , Cirurgia Assistida por Computador/métodos , Fraturas Zigomáticas/cirurgia , Adulto , Pontos de Referência Anatômicos/diagnóstico por imagem , Assimetria Facial/prevenção & controle , Feminino , Humanos , Imagem Tridimensional , Masculino , Fraturas Maxilares/complicações , Fraturas Maxilares/diagnóstico por imagem , Órbita/diagnóstico por imagem , Órbita/cirurgia , Tomografia Computadorizada Espiral , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Fraturas Zigomáticas/complicações , Fraturas Zigomáticas/diagnóstico por imagem
14.
J Craniomaxillofac Surg ; 47(2): 245-254, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30600197

RESUMO

PURPOSE: To analyze three-dimensional (3D) nasolabial forms and upper lip surface symmetry after primary lip repair in children with unilateral cleft lip and palate (UCLP). METHODS: Subjects were 22 Japanese children with complete UCLP who underwent primary lip repair and were followed-up for 4-6 years. The 3D coordinates of facial landmarks and the angle and radius of the approximate nasal alar circle were calculated. Upper lip surface symmetry was analyzed using histogram intersection. RESULTS: The nasal tip and columella base were slightly dislocated to the cleft side, and the midpoint of Cupid's bow shifted to the non-cleft side. The nasal alar and the top of Cupid's bow were reconstructed at the same height, while the approximate nasal alar circle was smaller on the cleft side. The mean value of similarity for upper lip surface symmetry was 0.82; a subject with a higher value had more symmetrical contour lines in the visualized surface image. CONCLUSIONS: Postoperative nasolabial forms were almost restored to symmetrical levels, while retaining a small nasal alar. Histogram intersection is applicable as a method for the quantitative evaluation of upper lip surface symmetry in UCLP.


Assuntos
Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Lábio/cirurgia , Nariz/patologia , Pontos de Referência Anatômicos/diagnóstico por imagem , Pontos de Referência Anatômicos/patologia , Fenda Labial/diagnóstico por imagem , Fenda Labial/patologia , Fissura Palatina/diagnóstico por imagem , Fissura Palatina/patologia , Feminino , Humanos , Imagem Tridimensional , Lactente , Lábio/diagnóstico por imagem , Lábio/patologia , Masculino , Nariz/diagnóstico por imagem
15.
Med Phys ; 46(3): 1286-1299, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30609058

RESUMO

PURPOSE: Radiological imaging and image interpretation for clinical decision making are mostly specific to each body region such as head and neck, thorax, abdomen, pelvis, and extremities. In this study, we present a new solution to trim automatically the given axial image stack into image volumes satisfying the given body region definition. METHODS: The proposed approach consists of the following steps. First, a set of reference objects is selected and roughly segmented. Virtual landmarks (VLs) for the objects are then identified by using principal component analysis and recursive subdivision of the object via the principal axes system. The VLs can be defined based on just the binary objects or objects with gray values also considered. The VLs may lie anywhere with respect to the object, inside or outside, and rarely on the object surface, and are tethered to the object. Second, a classic neural network regressor is configured to learn the geometric mapping relationship between the VLs and the boundary locations of each body region. The trained network is then used to predict the locations of the body region boundaries. In this study, we focus on three body regions - thorax, abdomen, and pelvis, and predict their superior and inferior axial locations denoted by TS(I), TI(I), AS(I), AI(I), PS(I), and PI(I), respectively, for any given volume image I. Two kinds of reference objects - the skeleton and the lungs and airways, are employed to test the localization performance of the proposed approach. RESULTS: Our method is tested by using low-dose unenhanced computed tomography (CT) images of 180 near whole-body 18 F-fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) scans (including 34 whole-body scans) which are randomly divided into training and testing sets with a ratio of 85%:15%. The procedure is repeated six times and three times for the case of lungs and skeleton, respectively, with different divisions of the entire data set at this proportion. For the case of using skeleton as a reference object, the overall mean localization error for the six locations expressed as number of slices (nS) and distance (dS) in mm, is found to be nS: 3.4, 4.7, 4.1, 5.2, 5.2, and 3.9; dS: 13.4, 18.9, 16.5, 20.8, 20.8, and 15.5 mm for binary objects; nS: 4.1, 5.7, 4.3, 5.9, 5.9, and 4.0; dS: 16.2, 22.7, 17.2, 23.7, 23.7, and 16.1 mm for gray objects, respectively. For the case of using lungs and airways as a reference object, the corresponding results are, nS: 4.0, 5.3, 4.1, 6.9, 6.9, and 7.4; dS: 15.0, 19.7, 15.3, 26.2, 26.2, and 27.9 mm for binary objects; nS: 3.9, 5.4, 3.6, 7.2, 7.2, and 7.6; dS: 14.6, 20.1, 13.7, 27.3, 27.3, and 28.6 mm for gray objects, respectively. CONCLUSIONS: Precise body region identification automatically in whole-body or body region tomographic images is vital for numerous medical image analysis and analytics applications. Despite its importance, this issue has received very little attention in the literature. We present a solution to this problem in this study using the concept of virtual landmarks. The method achieves localization accuracy within 2-3 slices, which is roughly comparable to the variation found in localization by experts. As long as the reference objects can be roughly segmented, the method with its learned VLs-to-boundary location relationship and predictive ability is transferable from one image modality to another.


Assuntos
Abdome/diagnóstico por imagem , Algoritmos , Doença , Pelve/diagnóstico por imagem , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons/métodos , Radiografia Torácica , Imagem Corporal Total/métodos , Pontos de Referência Anatômicos/diagnóstico por imagem , Estudos de Casos e Controles , Humanos , Processamento de Imagem Assistida por Computador/métodos , Modelos Estatísticos
16.
IEEE Trans Biomed Eng ; 66(5): 1195-1206, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30222548

RESUMO

In the field of computer-aided Alzheimer's disease (AD) diagnosis, jointly identifying brain diseases and predicting clinical scores using magnetic resonance imaging (MRI) have attracted increasing attention since these two tasks are highly correlated. Most of existing joint learning approaches require hand-crafted feature representations for MR images. Since hand-crafted features of MRI and classification/regression models may not coordinate well with each other, conventional methods may lead to sub-optimal learning performance. Also, demographic information (e.g., age, gender, and education) of subjects may also be related to brain status, and thus can help improve the diagnostic performance. However, conventional joint learning methods seldom incorporate such demographic information into the learning models. To this end, we propose a deep multi-task multi-channel learning (DM 2L) framework for simultaneous brain disease classification and clinical score regression, using MRI data and demographic information of subjects. Specifically, we first identify the discriminative anatomical landmarks from MR images in a data-driven manner, and then extract multiple image patches around these detected landmarks. We then propose a deep multi-task multi-channel convolutional neural network for joint classification and regression. Our DM 2L framework can not only automatically learn discriminative features for MR images, but also explicitly incorporate the demographic information of subjects into the learning process. We evaluate the proposed method on four large multi-center cohorts with 1984 subjects, and the experimental results demonstrate that DM 2L is superior to several state-of-the-art joint learning methods in both the tasks of disease classification and clinical score regression.


Assuntos
Doença de Alzheimer/classificação , Doença de Alzheimer/diagnóstico por imagem , Aprendizado Profundo , Interpretação de Imagem Assistida por Computador/métodos , Imagem por Ressonância Magnética/métodos , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Pontos de Referência Anatômicos/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Masculino
17.
J Knee Surg ; 32(7): 667-672, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29980153

RESUMO

Anatomic reconstruction of the popliteus tendon and arcuate complex results in superior functional and a biomechanically more stable outcome compared with extra-anatomic techniques in posterolateral rotatory knee instability. Although specific characteristics of the femoral and fibular footprint of the anatomic posterolateral reconstruction have been described, data for tibial tunnel placement while popliteus tendon reconstruction do not exist. The purpose of this study was to quantify reasonable parameters, which could be used in arthroscopy, fluoroscopy, or open surgery to determine the anatomic tibial drill tunnel position in popliteus tendon reconstruction. Thirty magnetic resonance images of 30 patients with an intact posterolateral corner (PLC) were analyzed to specify the ideal point for tibial fixation of a popliteus tendon graft with respect to 17 bony, cartilaginous, and ligamentous anatomic landmarks. The ideal point for tibial fixation was defined as the musculotendinous junction of the popliteus tendon near to the insertion of the popliteofibular ligament. In the coronal plane, the ideal tibial fixation was located at the crossing of a tangent to the fibular head, parallel to the joint line with a tangent to the medial border of the fibular head, and vertical to the joint line with a deviation of less than 1 mm. It was located 0.26 (±1.91) mm superior to the distal edge and 11.75 (±2.66) mm lateral to the lateral edge of the tibial posterior cruciate ligament footprint and only 8.68 (±2.81) mm lateral to the lateral edge of the neurovascular bundle. Interrater reliability to detect the correct position of the popliteus tendon graft footprint was almost perfect. The position for tibial drill tunnel placement in anatomic popliteus tendon reconstruction showed low interindividual differences. The present findings of the quantified anatomic landmarks might improve open, fluoroscopy, or arthroscopy guided PLC reconstruction.


Assuntos
Pontos de Referência Anatômicos/diagnóstico por imagem , Articulação do Joelho/diagnóstico por imagem , Imagem por Ressonância Magnética , Tendões/cirurgia , Tíbia/cirurgia , Adulto , Artroscopia , Feminino , Fíbula/diagnóstico por imagem , Humanos , Instabilidade Articular/cirurgia , Articulação do Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/cirurgia , Ligamento Cruzado Posterior/diagnóstico por imagem , Reprodutibilidade dos Testes , Estudos Retrospectivos , Tíbia/diagnóstico por imagem , Adulto Jovem
18.
IEEE Trans Med Imaging ; 38(4): 919-931, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30334750

RESUMO

In this paper, we propose a novel deep learning framework for anatomy segmentation and automatic landmarking. Specifically, we focus on the challenging problem of mandible segmentation from cone-beam computed tomography (CBCT) scans and identification of 9 anatomical landmarks of the mandible on the geodesic space. The overall approach employs three inter-related steps. In the first step, we propose a deep neural network architecture with carefully designed regularization, and network hyper-parameters to perform image segmentation without the need for data augmentation and complex post-processing refinement. In the second step, we formulate the landmark localization problem directly on the geodesic space for sparsely-spaced anatomical landmarks. In the third step, we utilize a long short-term memory network to identify the closely-spaced landmarks, which is rather difficult to obtain using other standard networks. The proposed fully automated method showed superior efficacy compared to the state-of-the-art mandible segmentation and landmarking approaches in craniofacial anomalies and diseased states. We used a very challenging CBCT data set of 50 patients with a high-degree of craniomaxillofacial variability that is realistic in clinical practice. The qualitative visual inspection was conducted for distinct CBCT scans from 250 patients with high anatomical variability. We have also shown the state-of-the-art performance in an independent data set from the MICCAI Head-Neck Challenge (2015).


Assuntos
Pontos de Referência Anatômicos/diagnóstico por imagem , Aprendizado Profundo , Interpretação de Imagem Assistida por Computador/métodos , Adolescente , Adulto , Algoritmos , Criança , Tomografia Computadorizada de Feixe Cônico/métodos , Anormalidades Craniofaciais/diagnóstico por imagem , Feminino , Humanos , Masculino , Mandíbula/diagnóstico por imagem , Adulto Jovem
19.
Eur J Orthop Surg Traumatol ; 29(3): 583-590, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30374641

RESUMO

The aim of our study was to compare the vertical fluoroscopic view of the wrist in extension and supination (ES) to the view in flexion and supination (FS) and determine which of the two views allowed the best visualization of four selected anatomical landmarks SDLR (radial styloid, dorsal radius cortex, Lister's tubercle and distal radioulnar joint). Our case series included 50 patients who had suffered a distal radius fracture and undergone an open reduction and internal fixation procedure with a volar locking plate. For each case, two fluoroscopic views were taken: ES (wrist extension and supination) (group I) and FS (wrist flexion and supination) (group II). Ten observers had to recognize the SDLR anatomical landmarks on 100 fluoroscopic skyline views (time 1) and 15 days later (time 2). The rate of recognition of the four anatomical landmarks was 78% in group I and 66% in group II (p < 0.001). The concordance rate of recognition of the four anatomical landmarks was mediocre (κ = 0.411). In conclusion, the vertical fluoroscopic skyline view in wrist extension and supination seems to be the most adequate view to assess the quality of the fracture reduction, the distal radioulnar joint and the length of the screws in open reduction and internal fixation of distal radius fractures with volar locking plates.


Assuntos
Pontos de Referência Anatômicos/diagnóstico por imagem , Fraturas do Rádio/diagnóstico por imagem , Fraturas do Rádio/cirurgia , Articulação do Punho/diagnóstico por imagem , Fluoroscopia/métodos , Fixação Interna de Fraturas , Humanos , Variações Dependentes do Observador , Redução Aberta , Supinação , Articulação do Punho/anatomia & histologia
20.
Laryngoscope ; 129(11): 2487-2490, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30582179

RESUMO

OBJECTIVE: To find ultrasonographic landmarks to define the lower limits of neck node levels 2 and 3. METHODS: Data were collected prospectively between February 2014 and January 2015. In total, 103 patients were recruited (50 men and 53 women), and the mean age was 50.9 years (range: 18-89). At the lower level of the hyoid, we classified ultrasonographic findings as hyoid type (HT)1 when the internal and external carotid arteries were visualized separately, HT2 when the internal and external carotid arteries joined together, and HT3 when the common carotid artery was visualized. At the lower border of the cricoid cartilage, we classified ultrasonographic findings as cricoid type (CT)1 when the omohyoid reached the medial half of the common carotid artery, CT2 when the omohyoid reached the lateral half of the common carotid artery, CT3 when the omohyoid reached the medial half of the internal jugular vein, and CT4 when the omohyoid reached the lateral half of the internal jugular vein. RESULTS: At the lower border of the hyoid, HT1 was most commonly observed in 59.2%, whereas HT2 and HT3 were observed in 31.3% and 9.7%, respectively. At the lower border of the cricoid cartilage, CT3 was most commonly observed in 52.9%, whereas CT2, CT4, and CT1 were observed in 20.4%, 14.1%, and 12.6%, respectively. CONCLUSION: HT1 and CT3 can be suggested ultrasonographic landmarks for the lower limits of levels 2 and 3, respectively. LEVEL OF EVIDENCE: 2. Laryngoscope, 129:2487-2490, 2019.


Assuntos
Pontos de Referência Anatômicos/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Linfonodos/diagnóstico por imagem , Pescoço/diagnóstico por imagem , Ultrassonografia/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Osso Hioide/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Valores de Referência , Adulto Jovem
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