Factors influencing development, utility, and new directions in medical imaging: from magnetic resonance to x rays

1997 ◽  
Author(s):  
Jenghwa Chang ◽  
Randall L. Barbour
2021 ◽  
Vol 1 (2) ◽  
pp. 71-80
Author(s):  
Revella E. A. Armya Armya ◽  
Adnan Mohsin Abdulazeez

Medical image segmentation plays an essential role in computer-aided diagnostic systems in various applications. Therefore, researchers are attracted to apply new algorithms for medical image processing because it is a massive investment in developing medical imaging methods such as dermatoscopy, X-rays, microscopy, ultrasound, computed tomography (CT), positron emission tomography, and magnetic resonance imaging. (Magnetic Resonance Imaging), So segmentation of medical images is considered one of the most important medical imaging processes because it extracts the field of interest from the Return on investment (ROI) through an automatic or semi-automatic process. The medical image is divided into regions based on the specific descriptions, such as tissue/organ division in medical applications for border detection, tumor detection/segmentation, and comprehensive and accurate detection. Several methods of segmentation have been proposed in the literature, but their efficacy is difficult to compare. To better address, this issue, a variety of measurement standards have been suggested to decide the consistency of the segmentation outcome. Unsupervised ranking criteria use some of the statistics in the hash score based on the original picture. The key aim of this paper is to study some literature on unsupervised algorithms (K-mean, K-medoids) and to compare the working efficiency of unsupervised algorithms with different types of medical images.


2006 ◽  
Vol 11 (6) ◽  
pp. 4-7
Author(s):  
Charles N. Brooks ◽  
Richard E. Strain ◽  
James B. Talmage

Abstract The primary function of the acetabular labrum, like that of the glenoid, is to deepen the socket and improve joint stability. Tears of the acetabular labrum are common in older adults but occur in all age groups and with equal frequency in males and females. The AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), Fifth Edition, is silent about rating tears, partial or complete excision, or repair of the acetabular labrum. Provocative tests to detect acetabular labrum tears involve hip flexion and rotation; all rely on production of pain in the groin (typically), clicking, and/or locking with passive or active hip motions. Diagnostic tests or procedures rely on x-rays, conventional arthrography, computerized tomography, magnetic resonance imaging (MRI), magnetic resonance arthrography (MRA), and hip arthroscopy. Hip arthroscopy is the gold standard for diagnosis but is the most invasive and most likely to result in complications, and MRA is about three times more sensitive and accurate in detecting acetabular labral tears than MRI alone. Surgical treatment for acetabular labrum tears usually consists of arthroscopic debridement; results tend to be better in younger patients. In general, an acetabular labral tear, partial labrectomy, or labral repair warrants a rating of 2% lower extremity impairment. Evaluators should avoid double dipping (eg, using both a Diagnosis-related estimates and limited range-of-motion tests).


Reumatismo ◽  
2016 ◽  
Vol 68 (2) ◽  
pp. 72 ◽  
Author(s):  
M. Lorenzin ◽  
A. Ortolan ◽  
P. Frallonardo ◽  
S. Vio ◽  
C. Lacognata ◽  
...  

Our aim was to determine the prevalence of spine and sacroiliac joint (SIJ) lesions on magnetic resonance imaging (MRI) in patients with early axial spondyloarthritis (axSpA) and their correlation with disease activity indices. Sixty patients with low back pain (LBP) (≥3 months, ≤2 years, onset ≤45 years), attending the SpA-clinic of the Unità Operativa Complessa Reumatologia of Padova [SpondyloArthritis-Caught-Early (SPACE) study], were studied following a protocol including physical examination, questionnaires, laboratory tests, X-rays and spine and SIJ MRI. Positive spine and SIJ MRI and X-rays images were scored independently by 2 readers using the SPARCC method, modified Stoke ankylosing spondylitis spine score and New York criteria. The axial pain and localization of MRI-lesions were referred to 4 sites: cervical/thoracic/lumbar spine and SIJ. All patients were classified into three groups: patients with signs of radiographic sacroiliitis (r-axSpA), patients without signs of r-axSpA but with signs of sacroiliitis on MRI (nr-axSpA MRI SIJ+), patients without signs of sacroiliitis on MRI and X-rays (nr-axSpA MRI SIJ-). The median age at LBP onset was 29.05±8.38 years; 51.6% of patients showed bone marrow edema (BME) in spine-MRI and 56.7% of patients in SIJ-MRI. Signs of enthesitis were found in 55% of patients in the thoracic district. Of the 55% of patients with BME on spine-MRI, 15% presented presented a negative SIJMRI. There was a significant difference between these cohorts with regard to the prevalence of radiographic sacroiliitis, active sacroiliitis on MRI and SPARCC SIJ score. The site of pain correlated statistically with BME lesions in thoracic and buttock districts. Since positive spine-MRI images were observed in absence of sacroiliitis, we can hypothesize that this finding could have a diagnostic significance in axSpA suspected axSpA.


Author(s):  
Tushar Kanti Bera ◽  
J. Nagaraju

Looking into the human body is very essential not only for studying the anatomy and physiology, but also for diagnosing a disease or illness. Doctors always try to visualize an organ or body part in order to study its physiological and anatomical status for understanding and/or treating its illness. This necessity introduced the diagnostic tool called medical imaging. The era of medical imaging started in 1895, when Roentgen discovered the magical powerful invisible rays called X-rays. Gradually the medical imaging introduced X-Ray CT, Gamma Camera, PET, SPECT, MRI, USG. Recently medical imaging field is enriched with comparatively newer tomographic imaging modalities like Electrical Impedance Tomography (EIT), Diffuse Optical Tomography (DOT), Optical Coherence Tomography (OCT), and Photoacaustic Tomography (PAT). The EIT has been extensively researched in different fields of science and engineering due to its several advantages. This chapter will present a brief review on the available medical imaging modalities and focus on the need of an alternating method. EIT will be discussed with its physical and mathematical aspects, potentials, and challenges.


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