Combining Mean and Standard Deviation of Hounsfield Unit Measurements from Preoperative CT Allows More Accurate Prediction of Urinary Stone Composition Than Mean Hounsfield Units Alone

2016 ◽  
Vol 30 (4) ◽  
pp. 453-459 ◽  
Author(s):  
Thomas Tailly ◽  
Yaniv Larish ◽  
Brandon Nadeau ◽  
Philippe Violette ◽  
Leonard Glickman ◽  
...  
Keyword(s):  
Standard Deviation ◽  
Hounsfield Unit ◽  
Urinary Stone ◽  
Accurate Prediction ◽  
Hounsfield Units ◽  
Stone Composition ◽  
Preoperative Ct

Hounsfield unit density in the determination of urinary stone composition

Urology ◽  
2001 ◽  
Vol 58 (2) ◽  
pp. 170-173 ◽  
Author(s):  
Garrick Motley ◽  
Neal Dalrymple ◽  
Christine Keesling ◽  
Joseph Fischer ◽  
William Harmon
Keyword(s):  
Hounsfield Unit ◽  
Urinary Stone ◽  
Stone Composition ◽  
Unit Density

The Efficacy of Non-Contrast Helical Computed Tomography in the Prediction of Urinary Stone Composition In Vivo

2003 ◽  
Vol 31 (1) ◽  
pp. 1-5 ◽  
Author(s):  
A Demirel ◽  
S Suma
Keyword(s):  
Computed Tomography ◽  
Hounsfield Unit ◽  
Urinary Stone ◽  
Urinary Stones ◽  
Helical Computed Tomography ◽  
Surgical Removal ◽  
Stone Composition ◽  
Acute Flank Pain ◽  
The Mean

The composition of urinary stones was predicted on the basis of the differences in their Hounsfield unit (HU) densities as detected by in vivo non-contrast helical computed tomography (NCHCT). A total of 87 stones, which had been obtained from patients admitted to the emergency department with acute flank pain, were analysed biochemically. These stones had been visualized by NCHCT before spontaneous passage, ureteroscopic extraction or surgical removal, and their HU densities had been recorded. The HU densities of the stones were compared with the results of biochemical analysis. The mean HU densities of the stones composed of calcium oxalate ( n = 54), struvite ( n = 19) and uric acid ( n = 14) were 812 ± 135, 614 ± 121 and 413 ± 143, respectively. The differences between the mean HU densities of these three stone types were statistically significant. This initial clinical study demonstrated that in vivo NCHCT analysis may be used to predict the composition of urinary stones.

Bubble study as a medium of contrast for computerized tomography coronary angiography. (Preprint)

2020 ◽  
Author(s):  
Vijay Shah ◽  
Justyn Huang
Keyword(s):  
Pulmonary Artery ◽  
Diagnostic Yield ◽  
Negative Contrast ◽  
Hounsfield Unit ◽  
Hounsfield Units ◽  
Computed Tomographic ◽  
Invasive Test ◽  
Clinical Difference ◽  
Contrast Ct ◽  
Scan Protocol

BACKGROUND Computed tomographic coronary angiogram (CTCA) is a non-invasive test with a negative predictive value of nearly 100% for the detection of coronary artery study. While diagnostic yield of a dedicated CTCA with bubble contrast is not yet evaluated OBJECTIVE To assess the diagnostic performance of injected bubble contrast and ability to measure difference in hounsfield units and use it as a "negative contrast" in computed tomographic METHODS This is a single center, single patient study. Baseline acquisition of a non-contrast CT scan was acquired to get hounsfield unit count in the aorta and pulmonary artery- (Calcium scan protocol) 1.4 mGy (19.5 mGy/cm). Secondly, Echo contrasts (Definity) - 5mls was injected and an echocardiogram confirmed filling in the aortic region. Finally, bubble contrast (1ml air, 8mls water and 1mls blood was drawn up and agitated through a 3 way tap) - was injected, a timing run was initiated to calculate for the bubbles to opacity the pulmonary artery. The same scan protocol was used– 1.4 mGy (19.5 mGy/cm). RESULTS Hounsfield units’ difference in the aorta and pulmonary artery from baseline compared to echo contrast and bubble contrast were not significant. CONCLUSIONS We believe this is the first ever recorded case to use bubbles as CT contrast. While results were not significant, secondary to small volume of bubbles injected. Further research needs to be implemented to assess clinical difference with amount of bubbles and volume required. CLINICALTRIAL Single centre study

Influence of chemical urinary stone composition on treatment method choice

2017 ◽  
Vol 16 (5) ◽  
pp. e2188
Author(s):  
J. Purvaneckas ◽  
R. Kavaliauskaitė ◽  
A. Želvys
Keyword(s):  
Treatment Method ◽  
Urinary Stone ◽  
Stone Composition ◽  
Method Choice

scholarly journals Urinary stone composition analysis and clinical characterization of 1520 patients in central China

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Daling Zhang ◽  
Songchao Li ◽  
Zhengguo Zhang ◽  
Ningyang Li ◽  
Xiang Yuan ◽  
...  
Keyword(s):  
Calcium Oxalate ◽  
Urinary Stone ◽  
Geographic Region ◽  
Central China ◽  
Urinary Stones ◽  
Composition Analysis ◽  
Stone Composition ◽  
Calcium Oxalate Stones ◽  
Significant Difference ◽  
Lower Urinary

AbstractA total of 1520 patients with urinary stones from central China were collected and analysed by Fourier transform infrared spectroscopy between October 1, 2016 and December 31, 2019. For all patients, age, sex, comorbidities, stone location, laboratory examination and geographic region were collected. The most common stone component was calcium oxalate (77.5%), followed by calcium phosphate (8.7%), infection stone (7.6%), uric acid (UA) stone (5.3%)and cystine (0.9%). The males had more calcium oxalate stones (p < 0.001), while infection stone and cystine stones occurred more frequently in females (p < 0.001). The prevalence peak occurred at 41–60 years in both men and women. UA stones occurred frequently in patients with lower urinary pH (p < 0.001), while neutral urine or alkaline urine (p < 0.001) and urinary infection (p < 0.001) were more likely to be associated with infection stone stones. Patients with high levels of serum creatinine were more likely to develop UA stones (p < 0.001). The proportion of UA stones in diabetics was higher (p < 0.001), and the incidence of hypertension was higher in patients with UA stones (p < 0.001). Compared to the other types, more calcium oxalate stones were detected in the kidneys and ureters (p < 0.001), whereas struvite stones were more frequently observed in the lower urinary tract (p = 0.001). There was no significant difference in stone composition across the Qinling-Huaihe line in central China except UA stones, which were more frequently observed in patients south of the line (p < 0.001).

Pediatric Urinary Stone Composition in the United States

2012 ◽  
Vol 187 (6) ◽  
pp. 2182-2187 ◽  
Author(s):  
J. Scott Gabrielsen ◽  
Robert J. Laciak ◽  
Elizabeth L. Frank ◽  
Molly McFadden ◽  
Cory S. Bates ◽  
...  
Keyword(s):  
United States ◽  
The United States ◽  
Urinary Stone ◽  
Stone Composition

scholarly journals The association between lower Hounsfield units on computed tomography and cage subsidence after lateral lumbar interbody fusion

2020 ◽  
Vol 49 (2) ◽  
pp. E8
Author(s):  
Zhuo Xi ◽  
Praveen V. Mummaneni ◽  
Minghao Wang ◽  
Huibing Ruan ◽  
Shane Burch ◽  
...  
Keyword(s):  
Interbody Fusion ◽  
Screw Fixation ◽  
Pedicle Screw Fixation ◽  
Lumbar Interbody Fusion ◽  
Hounsfield Units ◽  
Cage Subsidence ◽  
Preoperative Ct ◽  
Grade Ii ◽  
The Mean ◽  
Grade Iii

OBJECTIVEOne vexing problem after lateral lumbar interbody fusion (LLIF) surgery is cage subsidence. Low bone mineral density (BMD) may contribute to subsidence, and BMD is correlated with Hounsfield units (HUs) on CT. The authors investigated if lower HU values correlated with subsidence after LLIF.METHODSA retrospective study of patients undergoing single-level LLIF with pedicle screw fixation for degenerative conditions at the University of California, San Francisco, by 6 spine surgeons was performed. Data on demographics, cage parameters, preoperative HUs on CT, and postoperative subsidence were collected. Thirty-six–inch standing radiographs were used to measure segmental lordosis, disc space height, and subsidence; data were collected immediately postoperatively and at 1 year. Subsidence was graded using a published grade of disc height loss: grade 0, 0%–24%; grade I, 25%–49%; grade II, 50%–74%; and grade III, 75%–100%. HU values were measured on preoperative CT from L1 to L5, and each lumbar vertebral body HU was measured 4 separate times.RESULTSAfter identifying 138 patients who underwent LLIF, 68 met the study inclusion criteria. All patients had single-level LLIF with pedicle screw fixation. The mean follow-up duration was 25.3 ± 10.4 months. There were 40 patients who had grade 0 subsidence, 15 grade I, 9 grade II, and 4 grade III. There were no significant differences in age, sex, BMI, or smoking. There were no significant differences in cage sizes, cage lordosis, and preoperative disc height. The mean segmental HU (the average HU value of the two vertebrae above and below the LLIF) was 169.5 ± 45 for grade 0, 130.3 ± 56.2 for grade I, 100.7 ± 30.2 for grade II, and 119.9 ± 52.9 for grade III (p < 0.001). After using a receiver operating characteristic curve to establish separation criteria between mild and severe subsidence, the most appropriate threshold of HU value was 135.02 between mild and severe subsidence (sensitivity 60%, specificity 92.3%). After univariate and multivariate analysis, preoperative segmental HU value was an independent risk factor for severe cage subsidence (p = 0.017, OR 15.694, 95% CI 1.621–151.961).CONCLUSIONSLower HU values on preoperative CT are associated with cage subsidence after LLIF. Measurement of preoperative HU values on CT may be useful when planning LLIF surgery.

Abstract T P10: Hounsfield Unit Value and Clot Length in the Acutely Occlude Vessel and Time Required to Achieve Thrombectomy, Complications and Outcome

Stroke ◽  
2014 ◽  
Vol 45 (suppl_1) ◽  
Author(s):  
Alejandro Spiotta ◽  
Jan Vargas ◽  
Harris Hawk ◽  
Raymond Turner ◽  
Imran Chaudry ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Functional Outcome ◽  
Hounsfield Unit ◽  
Hounsfield Units ◽  
Unit Value ◽  
Procedural Complications ◽  
Noncontrast Ct ◽  
Time Required

Introduction: Intra-arterial therapy for acute ischemic stroke (AIS) now has an established role. We investigated if Hounsfield Units (HU) quantification on noncontrast CT is associated with ease and efficacy of mechanical thrombectomy and outcomes. Methods: We retrospectively studied a prospectively maintained database of cases of acute ischemic stroke that underwent intra-arterial therapy between May 2008 and August 2012. Functional outcome was assessed by ninety-day follow up modified Rankin Scale (mRS). Patients were dichotomized base on time to recanalization. Hounsfield units were calculated on head CT. Thrombus location and length were determined on CT angiography. Simple linear regression was used to analyze the association between clot length, average HU, and other clinical variables. Results: 141 patients were included. There was no difference in clot length or average HU among patients with good recanalization achieved within an hour compared to those in which procedures extended beyond an hour. There was no relationship between clot length or density and recanalization. The thrombus length and density were not significantly different between patients with procedural complications and those without. The presence of post procedure intracranial hemorrhage was not associated with thrombus length or density. Ninety day mRS was not associated with thrombus length or density. Conclusions: We have not found any significant associations between either thrombus length or density and likelihood of recanalization, time to achieve recanalization, intraprocedural complications, postprocedural hemorrhage or functional outcome at ninety days. These results do not support a predictive value for thrombus quantification in the evaluation of AIS.

Does smoking have any effect on urinary stone composition and the distribution of trace elements in urine and stones?

2009 ◽  
Vol 37 (6) ◽  
pp. 317-322 ◽  
Author(s):  
Marcin Słojewski ◽  
Bogusław Czerny ◽  
Krzysztof Safranow ◽  
Marek Droździk ◽  
Andrzej Pawlik ◽  
...  
Keyword(s):  
Trace Elements ◽  
Urinary Stone ◽  
Stone Composition ◽  
Distribution Of Trace Elements
Sign in / Sign up

Export Citation Format

Share Document