Emergency unenhanced multi-slice computed tomography in suspected urinary calculi—with dose reduction method (care dose 4D)

Objectives: To assess urinary calculi and the secondary signs of obstruction, in patients referred from the accident and emergency department, by unenhanced computed tomography examination and to review the radiation dose the patients received with the use of automatic dose modulation technique, car...

Full description

Bibliographic Details
Main Authors: Syed Nabir, Vajjala Ravi Kumar
Format: Article
Language:English
Published: HBKU Press 2012-09-01
Series:Journal of Emergency Medicine, Trauma and Acute Care
Online Access:http://www.qscience.com/doi/pdf/10.5339/jemtac.2012.15
id doaj-a82ee150af9e4c81bb7cd228d1796e40
record_format Article
spelling doaj-a82ee150af9e4c81bb7cd228d1796e402020-11-24T21:32:10ZengHBKU PressJournal of Emergency Medicine, Trauma and Acute Care1999-70861999-70942012-09-012012110.5339/jemtac.2012.15Emergency unenhanced multi-slice computed tomography in suspected urinary calculi—with dose reduction method (care dose 4D)Syed NabirVajjala Ravi KumarObjectives: To assess urinary calculi and the secondary signs of obstruction, in patients referred from the accident and emergency department, by unenhanced computed tomography examination and to review the radiation dose the patients received with the use of automatic dose modulation technique, care dose 4D. Material and methods: Medical records of unenhanced multi-slice computed tomography (MSCT) examinations for 114 patients referred to the emergency department for analysis of suspected urinary calculi were reviewed retrospectively. Their treatment involved automatic tube current modulation, a dose reduction method (care dose 4D), in Hamad General Hospital. The cases were analyzed for the presence of stones, size, site, density and the secondary signs of obstruction, namely hydronephrosis, hydroureter, perinephric fat stranding, peri-ureteric fat stranding and renal enlargement. A search for alternate diagnosis was made if no stone was found. The final diagnosis was noted from the discharge summary in medical records. The radiation dose, Computed Tomographic Dose Index volume (CTDI) and Dose Length Product (DLP) in each patient was recorded from patient protocol. Results: Of 114 patients referred to CT scan for suspected urinary calculi, between March and June 2008, urinary calculi were noted in 75.4 %. An alternate diagnosis was offered to 5.3 % and a diagnosis of normal was given to 19.3 %. The size of stones detected varied from 2mm-35mm. Density of stones varied from 110-1250 hounsfield units (HU). Solitary stones were seen in 54.4 % of cases observed and multiple stones in 22 %. Renal stones were observed in 6.1 % of cases, urteric stones in 26.3%, vesico-uretric junction stones in 18.4%, multiple sites in 23.7%. Hydronephrosis was seen in 68% of cases, hydroureter in 63%, perinephric fat stranding in 51%, periureteral fat stranding in 34%, ureteric rim sign in 28% and renomegaly in 24%. Time interval between onset of symptoms to imaging varied from 4 to 12 hours. The radiation dose, CTDI, ranged from 6.5-15.8 mGy and DLP from 257 to 918 mGy/cm with the use of automatic tube current modulation, care dose 4D. Final diagnosis and MSCT diagnosis were in concordance in 86 (75% of) patients of renal calculi and alternate diagnosis in 6 (5.3%) of patients and normal in rest of the patients. Conclusion: In clinically-suspected urinary calculi, unenhanced MSCT of abdomen with the use of care dose 4D, an automatic tube current modulation technique, is a fast and reliable investigation in an emergency setting to detect stones and secondary signs of obstruction. It offers alternate diagnosis with substantial reduction in radiation dose—both the computed tomography dose index (CTDI) and dose length product (DLP). http://www.qscience.com/doi/pdf/10.5339/jemtac.2012.15
collection DOAJ
language English
format Article
sources DOAJ
author Syed Nabir
Vajjala Ravi Kumar
spellingShingle Syed Nabir
Vajjala Ravi Kumar
Emergency unenhanced multi-slice computed tomography in suspected urinary calculi—with dose reduction method (care dose 4D)
Journal of Emergency Medicine, Trauma and Acute Care
author_facet Syed Nabir
Vajjala Ravi Kumar
author_sort Syed Nabir
title Emergency unenhanced multi-slice computed tomography in suspected urinary calculi—with dose reduction method (care dose 4D)
title_short Emergency unenhanced multi-slice computed tomography in suspected urinary calculi—with dose reduction method (care dose 4D)
title_full Emergency unenhanced multi-slice computed tomography in suspected urinary calculi—with dose reduction method (care dose 4D)
title_fullStr Emergency unenhanced multi-slice computed tomography in suspected urinary calculi—with dose reduction method (care dose 4D)
title_full_unstemmed Emergency unenhanced multi-slice computed tomography in suspected urinary calculi—with dose reduction method (care dose 4D)
title_sort emergency unenhanced multi-slice computed tomography in suspected urinary calculi—with dose reduction method (care dose 4d)
publisher HBKU Press
series Journal of Emergency Medicine, Trauma and Acute Care
issn 1999-7086
1999-7094
publishDate 2012-09-01
description Objectives: To assess urinary calculi and the secondary signs of obstruction, in patients referred from the accident and emergency department, by unenhanced computed tomography examination and to review the radiation dose the patients received with the use of automatic dose modulation technique, care dose 4D. Material and methods: Medical records of unenhanced multi-slice computed tomography (MSCT) examinations for 114 patients referred to the emergency department for analysis of suspected urinary calculi were reviewed retrospectively. Their treatment involved automatic tube current modulation, a dose reduction method (care dose 4D), in Hamad General Hospital. The cases were analyzed for the presence of stones, size, site, density and the secondary signs of obstruction, namely hydronephrosis, hydroureter, perinephric fat stranding, peri-ureteric fat stranding and renal enlargement. A search for alternate diagnosis was made if no stone was found. The final diagnosis was noted from the discharge summary in medical records. The radiation dose, Computed Tomographic Dose Index volume (CTDI) and Dose Length Product (DLP) in each patient was recorded from patient protocol. Results: Of 114 patients referred to CT scan for suspected urinary calculi, between March and June 2008, urinary calculi were noted in 75.4 %. An alternate diagnosis was offered to 5.3 % and a diagnosis of normal was given to 19.3 %. The size of stones detected varied from 2mm-35mm. Density of stones varied from 110-1250 hounsfield units (HU). Solitary stones were seen in 54.4 % of cases observed and multiple stones in 22 %. Renal stones were observed in 6.1 % of cases, urteric stones in 26.3%, vesico-uretric junction stones in 18.4%, multiple sites in 23.7%. Hydronephrosis was seen in 68% of cases, hydroureter in 63%, perinephric fat stranding in 51%, periureteral fat stranding in 34%, ureteric rim sign in 28% and renomegaly in 24%. Time interval between onset of symptoms to imaging varied from 4 to 12 hours. The radiation dose, CTDI, ranged from 6.5-15.8 mGy and DLP from 257 to 918 mGy/cm with the use of automatic tube current modulation, care dose 4D. Final diagnosis and MSCT diagnosis were in concordance in 86 (75% of) patients of renal calculi and alternate diagnosis in 6 (5.3%) of patients and normal in rest of the patients. Conclusion: In clinically-suspected urinary calculi, unenhanced MSCT of abdomen with the use of care dose 4D, an automatic tube current modulation technique, is a fast and reliable investigation in an emergency setting to detect stones and secondary signs of obstruction. It offers alternate diagnosis with substantial reduction in radiation dose—both the computed tomography dose index (CTDI) and dose length product (DLP).
url http://www.qscience.com/doi/pdf/10.5339/jemtac.2012.15
work_keys_str_mv AT syednabir emergencyunenhancedmultislicecomputedtomographyinsuspectedurinarycalculiwithdosereductionmethodcaredose4d
AT vajjalaravikumar emergencyunenhancedmultislicecomputedtomographyinsuspectedurinarycalculiwithdosereductionmethodcaredose4d
_version_ 1725958372569645056