MEASUREMENT VALIDITY AND IMAGE QUALITY ASSESSMENT OF LOW DOSE CT SCAN IN ASCENDING AORTIC ANEURYSM EVALUATION, A RETROSPECTIVE STUDY

Objectives: For patients with intracranial hemorrhage (ICH), routine follow-up computed tomography (CT) scans are typically required to monitor the progression of intracranial pathology. Remarkable levels of radiation exposure are accumulated during repeated CT scan. However, the effects and associated risks have still remained elusive. This study presented an effective approach to quantify organ-specific radiation dose of repeated CT scans of head for patients with ICH. We also indicated whether a low-dose CT scan may reduce radiation exposure and keep the image quality highly acceptable for diagnosis. Methods: Herein, 72 patients with a history of ICH were recruited. The patients were divided into 4 groups and underwent CT scan of head with different tube current–time products (250, 200, 150, and 100 mAs). Two experienced radiologists visually rated scores of quality of images according to objective image noise, sharpness, diagnostic acceptability, and artifacts due to physiological noise on the same workstation. Organ-/tissue-specific radiation doses were analyzed using Radimetrics. Results: In conventional CT scan group, signal to noise ratio (SNR) and contrast to noise ratio (CNR) of ICH images were significantly higher than those in normal brain structures. Reducing the tube current–time product may decrease the image quality. However, the predilection sites for ICH could be clearly identified. The SNR and CNR in the predilection sites for ICH were notably higher than other areas. The brain, eye lenses, and salivary glands received the highest radiation dose. Reducing tube current–time product from 250 to 100 mA can significantly reduce the radiation dose. Discussion: We demonstrated that low-dose CT scan of head can still provide reasonable images for diagnosing ICH. The radiation dose can be reduced to ∼45% of the conventional CT scan group.

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Fusion of image quality assessment and transfer learning for COVID19 detection using CT scan image

10.1145/3490035.3490307 ◽

2021 ◽

Author(s):

Kiruthika S. ◽

Masilamani V. ◽

Pratik Joshi

Keyword(s):

Image Quality ◽

Quality Assessment ◽

Ct Scan ◽

Transfer Learning ◽

Image Quality Assessment

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Image quality assessment of low-dose protocols in cone beam computed tomography of the anterior maxilla

Oral Surgery Oral Medicine Oral Pathology and Oral Radiology ◽

10.1016/j.oooo.2021.10.001 ◽

2021 ◽

Author(s):

Randi Lynds Ihlis ◽

Nils Kadesjö ◽

Georgios Tsilingaridis ◽

Daniel Benchimol ◽

Xie Qi Shi

Keyword(s):

Computed Tomography ◽

Image Quality ◽

Quality Assessment ◽

Cone Beam Computed Tomography ◽

Low Dose ◽

Image Quality Assessment ◽

Cone Beam ◽

Anterior Maxilla

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Low-dose head computed tomography in children: a single institutional experience in pediatric radiation risk reduction

Journal of Neurosurgery Pediatrics ◽

10.3171/2013.7.peds12631 ◽

2013 ◽

Vol 12 (4) ◽

pp. 406-410 ◽

Cited By ~ 32

Author(s):

Ryan P. Morton ◽

Renee M. Reynolds ◽

Rohan Ramakrishna ◽

Michael R. Levitt ◽

Richard A. Hopper ◽

...

Keyword(s):

Image Quality ◽

Ct Scan ◽

Low Dose ◽

Ct Scans ◽

Head Ct ◽

Full Dose ◽

Low Dose Ct ◽

Children's Hospital ◽

Ct Protocol ◽

Children’S Hospital

Object In this study, the authors describe their experience with a low-dose head CT protocol for a preselected neurosurgical population at a dedicated pediatric hospital (Seattle Children's Hospital), the largest number of patients with this protocol reported to date. Methods All low-dose head CT scans between October 2011 and November 2012 were reviewed. Two different low-dose radiation dosages were used, at one-half or one-quarter the dose of a standard head CT scan, based on patient characteristics agreed upon by the neurosurgery and radiology departments. Patient information was also recorded, including diagnosis and indication for CT scan. Results Six hundred twenty-four low-dose head CT procedures were performed within the 12-month study period. Although indications for the CT scans varied, the most common reason was to evaluate the ventricles and catheter placement in hydrocephalic patients with shunts (70%), followed by postoperative craniosynostosis imaging (12%). These scans provided adequate diagnostic imaging, and no patient required a follow-up full-dose CT scan as a result of poor image quality on a low-dose CT scan. Overall physician comfort and satisfaction with interpretation of the images was high. An additional 2150 full-dose head CT scans were performed during the same 12-month time period, making the total number of CT scans 2774. This value compares to 3730 full-dose head CT scans obtained during the year prior to the study when low-dose CT and rapid-sequence MRI was not a reliable option at Seattle Children's Hospital. Thus, over a 1-year period, 22% of the total CT scans were able to be converted to low-dose scans, and full-dose CT scans were able to be reduced by 42%. Conclusions The implementation of a low-dose head CT protocol substantially reduced the amount of ionizing radiation exposure in a preselected population of pediatric neurosurgical patients. Image quality and diagnostic utility were not significantly compromised.

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