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1.
Quant Imaging Med Surg ; 12(8): 4259-4271, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35919046

RESUMEN

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.

3.
Mol Med Rep ; 20(2): 1707-1715, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31257530

RESUMEN

Recent studies have reported structural and functional abnormalities in multiple brain regions of classical trigeminal neuralgia (CTN) patients. Differences in spontaneous neuronal activity between CTN patients and healthy subjects, however, remain unknown. The aim of the present study was to investigate alterations in brain activity by application of amplitude of low frequency fluctuation (ALFF), thus analyzing the correlation between durations of spontaneous pain intensity and ALFF values in CTN patients. A total of 28 CTN patients (male, n=12; female, n=16) and 28 healthy controls (HCs; male, n=12; female, n=16) matched for age and sex were enrolled. All subjects underwent resting­state functional magnetic resonance imaging and changes in spontaneous brain activity were investigated using an ALFF method. Receiver operating characteristic (ROC) curve analysis was applied to differentiate ALFF values of CTN patients from HCs. Altered ALFF values and clinical manifestations were evaluated using Pearson's correlation analysis. ALFF values of the bilateral inferior cerebellum, bilateral fusiform gyrus, right precentral gyrus, left inferior temporal gyrus, right superior cerebellum, left inferior occipital gyrus and right superior occipital gyrus were significantly higher in CTN patients when compared to HCs. ROC curve analysis of each brain revealed a near­perfect AUC accuracy. Pearson's correlation analysis revealed the visual analog scale of the right eye to be positively correlated with both left inferior temporal and occipital gyral findings, while episode duration likewise was positively associated with left inferior temporal gyral findings. CTN patients exhibited abnormal spontaneous activity in multiple brain regions closely related to pain regulation and perception, while VAS and CTN episode duration were positively correlated with ALFF signal values in some brain regions. The present findings provide further insight into the pathological mechanisms underlying CTN.


Asunto(s)
Encéfalo/diagnóstico por imagen , Neuralgia del Trigémino/diagnóstico por imagen , Adulto , Encéfalo/fisiopatología , Mapeo Encefálico , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Neuralgia del Trigémino/fisiopatología
4.
J Clin Densitom ; 22(3): 409-419, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-29307693

RESUMEN

This study aims to evaluate endplate/cortex fracture (ECF)-based method for detecting osteoporotic vertebral fracture (VF) in elderly Chinese population (age ≥ 65 years). The radiographs of 1954 elderly Chinese men (mean: 72.3 years) and 1953 elderly Chinese women (mean: 72.5 years) were evaluated according to Genant's morphometrical vertebral deformity (VD) severity criteria, as well as identified VF according to ECF without necessary requirement of VD. According to ECF, grade-1, -2, and -3 VF prevalence was 1.89%, 1.74%, and 2.25% in men, and 3.33%, 3.07%, and 5.89% in women, respectively. In men and women, 15.7% (35 of 223) and 34.5% (48 of 139) of vertebrae with VD grade-1 deformity were ECF(+, with fracture), respectively. In men and women, 89.7% (35 of 39) and 66.7% (48 of 72) of vertebrae with ECF grade-1 fracture had VD grade-1 deformity. For grade-1 change, ECF(+) subjects tended to have a lower BMD than the VD(+) subjects. In subjects with VD grade-2 deformity, those who were also EC (+) tended to have a lower BMD than those were ECF(-). In all grades, VD(-) and ECF(-) subjects tended to have highest BMD, whereas VD(+) and ECF(+) subjects tended to have lowest BMD. ECF may be more specific for assessing mild VF than the criteria based on vertebral deformity.


Asunto(s)
Algoritmos , Vértebras Lumbares/diagnóstico por imagen , Fracturas Osteoporóticas/diagnóstico por imagen , Fracturas de la Columna Vertebral/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Densidad Ósea , China/epidemiología , Femenino , Hong Kong/epidemiología , Humanos , Vértebras Lumbares/lesiones , Masculino , Fracturas Osteoporóticas/epidemiología , Prevalencia , Radiografía , Fracturas de la Columna Vertebral/epidemiología
5.
J Orthop Translat ; 15: 35-49, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30306044

RESUMEN

Despite years' research, the radiographic criteria for osteoporotic vertebral fracture and its grading remain debated. The importance of identifying vertebral endplate/cortex fracture (ECF) is being recognised; however, evaluation of osteoporotic ECF requires training and experience. This article aims to serve as a teaching material for radiologists/physicians or researchers to evaluate osteoporotic ECF. Emphasis is particularly dedicated to identifying ECF that may not be associated with apparent vertebral body collapse. We suggest a combined approach based on standardised radiologic evaluation by experts and morphometry measurement is the most appropriate approach to detect and classify osteoporotic vertebral fractures. THE TRANSLATIONAL POTENTIAL: A good understanding of radiologic anatomy of vertebrae and fracture signs of endplate/cortex are essential for spine fragility fracture assessment.

6.
Clin Spine Surg ; 30(5): E573-E577, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28525480

RESUMEN

STUDY DESIGN: A prospective study and a technique note. OBJECTIVES: To introduce a new entrance technique for C2 pedicle screw placement and to measure the related linear and angular parameters about the entrance point on computed tomography (CT) images. The safety of this technique for patients with atlantoaxial instability was also evaluated. BACKGROUND DATA: Although earlier studies have introduced different methods for C2 pedicle screw placement, the entry points and the angular parameters may be variable. Few studies have established a fixed entry point on the basis of the anatomic structure of C2 for pedicle screw placement. METHODS: A total of 60 dry C2 vertebrae were obtained for anatomic measurement in the study. The posterior bilateral nutrient foramens of C2 lamina were selected as the entry points for pedicle screw placement. The foramens were marked with needles and then the vertebrae underwent CT scan. The axial and sagittal planes of C2 pedicles were harvested and 4 linear and 2 angular parameters about the entry point were determined. After that, we used the entrance technique on 31 patients with atlantoaxial instability in a prospective study. CT of the cervical spine was performed to evaluate the safety of the entrance technique. RESULTS: The nutrient foramens exist in 97% of the left lamina and 93% of the right lamina of the C2 vertebra. The overall mean distance from the entry point (nutrient foramen) to the superior border of lamina (PSD), to the inferior border of lamina (PID), to the medial border of the pedicle (PMD), and the length of pedicle screw trajectory (PL, transit the pedicle center) were 3.32±0.63, 8.33±1.21, 6.85±1.00, and 24.47±1.51, respectively. The averaged transverse angle (α) on the axial plane and the superior angle (ß) on the sagittal plane were 19.83±3.83 and 30.12±6.02 degrees, respectively. Then, 31 patients underwent bilateral C2 pedicle screw fixation without screw violation into the spinal canal or vertebral artery injury by the new entrance technique. The overall mean angles α and ß and the length of the pedicle screw were 17.52±3.81 and 34.29±4.18 degrees and 25.85±2.06 mm, respectively. No statistical differences were found in these 3 parameters between the dry C2 vertebrae and the C2 vertebrae of patients who underwent the surgery (P>0.05). CONCLUSIONS: Using the posterior bilateral nutrient foramens of the C2 lamina as the entry point is a helpful intraoperative landmark for C2 pedicle screw placement.


Asunto(s)
Articulación Atlantoaxoidea/cirugía , Vértebras Cervicales/cirugía , Inestabilidad de la Articulación/cirugía , Tornillos Pediculares , Adulto , Vértebras Cervicales/diagnóstico por imagen , Femenino , Humanos , Imagenología Tridimensional , Inestabilidad de la Articulación/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X
7.
Eur Radiol ; 24(2): 441-8, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24126641

RESUMEN

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.


Asunto(s)
Vértebras Lumbares/diagnóstico por imagen , Espondilolistesis/epidemiología , Distribución por Edad , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Hong Kong/epidemiología , Humanos , Masculino , Prevalencia , Estudios Prospectivos , Radiografía , Factores de Riesgo , Sexismo , Espondilolistesis/diagnóstico por imagen
8.
Quant Imaging Med Surg ; 2(2): 142-4, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23256076

RESUMEN

Desmoid-type fibromatosis (DF) is a rare intermediately and locally aggressive tumor that occurs predominantly between puberty and 40 years, with female having higher incidence than male. This report describes a 48-year-old man with biopsy-proven DF in left intermuscular spatium of buttock and thigh. The mass had a wide longitudinal distribution from femoral neck level to popliteal fossa and measured about 40 cm. Plain CT showed a partially ill-defined mass with an irregular contour, with a density similar or slightly higher than skeletal muscle. On MR images, the tumor showed uneven signal in both T(1)WI and T(2)WI, mainly hyperintense to skeletal muscle and with stripe or patch-like markedly low signal. After contrast injection, the mass showed heterogeneous enhancement.

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