-
Radiography (London, England : 1995) Feb 2019Within medical imaging variations in patient size can generate challenges, especially when selecting appropriate acquisition parameters. This experiment sought to...
INTRODUCTION
Within medical imaging variations in patient size can generate challenges, especially when selecting appropriate acquisition parameters. This experiment sought to evaluate the impact of increasing body part thickness on image quality (IQ) and effective dose (E) and identify optimum exposure parameters.
METHODS
An anthropomorphic pelvis phantom was imaged with additional layers (1-15 cm) of animal fat as a proxy for increasing body thickness. Acquisitions used the automatic exposure control (AEC), 100 cm source to image distance (SID) and a range of tube potentials (70-110 kVp). IQ was evaluated physically and perceptually. E was estimated using PCXMC software.
RESULTS
For all tube potentials, signal to noise ratio (SNR) and contrast to noise ratio (CNR) deceased as body part thickness increased. 70 kVp produced the highest SNR (46.6-22.6); CNR (42.8-17.6). Visual grading showed that the highest IQ scores were achieved using 70 and 75 kVp. As thickness increases, E increased exponentially (r = 0.96; p < 0.001). Correlations were found between visual and physical IQ (SNR r = 0.97, p < 0.001; CNR r = 0.98, p < 0.001).
CONCLUSION
To achieve an optimal IQ across the range of thicknesses, lower kVp settings were most effective. This is at variance with professional practice as there is a tendency for radiographers to increase kVp as thickness increases. Dose reductions were experienced at higher kVp settings and are a valid method for optimisation when imaging larger patients.
Topics: Pelvis; Phantoms, Imaging; Radiation Dosage; Radiography
PubMed: 30599841
DOI: 10.1016/j.radi.2018.09.001 -
European Spine Journal : Official... Sep 2011There is a wide variation in the regional parameters used to describe the spine and sacro-pelvis in children and adolescents. There is a slight tendency for thoracic... (Review)
Review
There is a wide variation in the regional parameters used to describe the spine and sacro-pelvis in children and adolescents. There is a slight tendency for thoracic kyphosis and lumbar lordosis to increase with age. Pelvic incidence and pelvic tilt also tend to increase during growth, while sacral slope remains relatively stable. Strong knowledge of the close relationships between adjacent anatomical regions of the spine and sacro-pelvis is the key when evaluating and interpreting sagittal spino-pelvic alignment. The scheme of correlations between adjacent regional parameters needs to be preserved in order to maintain a balanced posture. The net resultant from these relationships between adjacent anatomical regions is best represented by parameters of sagittal global balance. C7 plumbline tends to move backwards from childhood to adulthood, where it stabilizes or slightly moves forward secondary to degenerative changes. C7 plumbline in front of both hip axis and center of the upper sacral endplate occurs in 29% of subjects aged 3-10 years, 12% of subjects aged between 10 and 18 years, and 14% of subjects aged 18 years or older. Therefore, although most normal subjects stand with a C7 plumbline behind the hip axis, a C7 plumbline in front of both hip axis and sacrum can be seen in normal individuals. However, progressive forward displacement of C7 plumbline should raise a suspicion for the risk of developing spinal pathology.
Topics: Adolescent; Child; Child, Preschool; Female; Humans; Male; Pelvis; Postural Balance; Spinal Diseases; Spine
PubMed: 21811824
DOI: 10.1007/s00586-011-1925-0 -
Radiographics : a Review Publication of... 2018Computed tomography (CT) is key to the assessment of hemodynamically stable patients with blunt or penetrating trauma to the abdomen and pelvis. Dual-energy (DE) CT is a... (Review)
Review
Computed tomography (CT) is key to the assessment of hemodynamically stable patients with blunt or penetrating trauma to the abdomen and pelvis. Dual-energy (DE) CT is a technology that allows acquisition of data at both high and low kilovolt peaks, allowing materials that have different x-ray absorption behaviors as a function of kilovolt peak (such as iodine) to be differentiated and quantified. DE CT has a variety of postprocessing applications that may be helpful in abdominal and pelvic trauma, including iodine-selective imaging, virtual monenergetic imaging, and virtual noncalcium imaging. Both iodine-selective imaging and virtual monoenergetic imaging can increase the conspicuity of traumatic solid-organ and hollow visceral injuries, making injuries easier to detect and categorize. Iodine-selective imaging, through the use of iodine maps and virtual noncontrast images, can assist in the evaluation of active contrast extravasation. Virtual noncalcium images can unmask bone marrow edema, improving detection of subtle fractures. The purpose of this review article is to familiarize radiologists with the basic physics and technical principles of DE CT, common postprocessing techniques, and the potential added value of DE CT in patients with abdominal and pelvic trauma. The technical limitations of DE CT are also reviewed, as are diagnostic pitfalls and common challenges in interpretation. RSNA, 2018.
Topics: Abdominal Injuries; Contrast Media; Diagnosis, Differential; Extravasation of Diagnostic and Therapeutic Materials; Humans; Pelvis; Tomography, X-Ray Computed
PubMed: 29528816
DOI: 10.1148/rg.2018170058 -
Seminars in Ultrasound, CT, and MR Oct 1991
Review
Topics: Child; Child, Preschool; Female; Genital Diseases, Female; Genital Diseases, Male; Humans; Infant; Infant, Newborn; Magnetic Resonance Imaging; Male; Pelvis; Urologic Diseases
PubMed: 1742057
DOI: No ID Found -
Radiologic Clinics of North America Jul 1992The increased use of MR imaging in the pediatric population is due to the lack of ionizing radiation, multiplanar imaging capability, and excellent tissue contrast... (Review)
Review
The increased use of MR imaging in the pediatric population is due to the lack of ionizing radiation, multiplanar imaging capability, and excellent tissue contrast differentiation. MR imaging is most commonly indicated in the evaluation of tumors to provide information about resectability and extent of lesions. It is also useful in the evaluation of congenital anomalies of the pelvic organs. This is a rapidly changing field; the development of fast-scanning techniques and contrast agents for the bowel should further improve the utilization of MR imaging in pediatrics.
Topics: Child; Female; Genital Diseases, Female; Humans; Magnetic Resonance Imaging; Pelvic Neoplasms; Pelvis
PubMed: 1631286
DOI: No ID Found -
La Radiologia Medica Mar 2004
-
Critical Reviews in Diagnostic Imaging 1989Magnetic resonance imaging (MRI) has become an important diagnostic method for the study of the female pelvis. It provides a noninvasive means of evaluating uterine... (Review)
Review
Magnetic resonance imaging (MRI) has become an important diagnostic method for the study of the female pelvis. It provides a noninvasive means of evaluating uterine zonal anatomy and can reflect the variable appearance of the female genital tract in response to different hormonal stimuli. It is considered a problem-solving technique for evaluating benign uterine and adnexal masses and is the primary imaging modality for staging endometrial, cervical, and vaginal carcinoma. It is also valuable in the assessment of vaginal agenesis and congenital uterine anomalies by providing information needed in surgical management. The role of MRI has not yet been established in the evaluation of ovarian carcinoma.
Topics: Female; Humans; Magnetic Resonance Imaging; Pelvis
PubMed: 2688676
DOI: No ID Found -
Ceskoslovenska Gynekologie Feb 1954
Topics: Bone Diseases; Pelvis
PubMed: 13150409
DOI: No ID Found -
Journal of Healthcare Engineering 2018The objective of this study was to develop and validate a novel 3D dynamic model of a pelvic side-impactor system. The biomechanical responses of a pelvic flexible model...
The objective of this study was to develop and validate a novel 3D dynamic model of a pelvic side-impactor system. The biomechanical responses of a pelvic flexible model (having .mnf file suffix) under the lateral impact load for predicting the bone fracture mechanism are investigated as well. The 3D solid model of the side-impactor system was imported into MSC/ADAMS software for analyzing the dynamic model, and the pelvic flexible model was extracted from the CT images of a Chinese female volunteer. The flexible model of the pelvis system was developed considering a wide range of mechanical properties in the bone complex and soft tissue to achieve a realistic biomechanical response during a lateral impact. Good agreements were achieved between the dynamic simulations and the experimental results of pelvic side impacts, in terms of the biomechanical criteria. The dynamic model of impactor system could be employed to investigate the hip protector effectiveness, improving the vehicle safety, and biomechanical response of the other human organs.
Topics: Accidents, Traffic; Aged; Biomechanical Phenomena; Biomedical Research; Equipment Design; Female; Fractures, Bone; Humans; Male; Middle Aged; Models, Biological; Pelvic Bones; Pelvis
PubMed: 30319741
DOI: 10.1155/2018/3083278 -
Best Practice & Research. Clinical... Feb 2006An in-depth knowledge of the anatomy of the pelvis and pelvic sidewall is necessary before a gynaecologist can even contemplate making an initial examination and start... (Review)
Review
An in-depth knowledge of the anatomy of the pelvis and pelvic sidewall is necessary before a gynaecologist can even contemplate making an initial examination and start management in cases of pelvic pathology or malignancy. This chapter provides basic information on gross pelvic anatomy structures that are of clinical relevance and discusses their correlation with medical imaging, especially magnetic resonance imaging (MRI). MRI is an ideal non-invasive technique in the assessment of normal anatomy and tissue characterization of pelvic pathology. The excellent soft-tissue contrast and the ability to direct multiplanar imaging and to demonstrate blood vessels without the use of intravenous contrast make MRI superior to other imaging modalities in the evaluation of pelvic abnormalities. The anatomical relation of the visceral organs, the differential zonal anatomy of the corpus uteri and the cyclical endometrial changes during the menstrual cycle are well depicted with MRI.
Topics: Autonomic Nervous System; Female; Genitalia, Female; Humans; Magnetic Resonance Imaging; Muscle, Skeletal; Pelvis; Urogenital System
PubMed: 16275093
DOI: 10.1016/j.bpobgyn.2005.09.001