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International Archives of... Jul 2022High-resolution computed tomography (HRCT) scans of the temporal bone are used to assess the bony erosion of the middle-ear structures whenever cholesteatoma is...
High-resolution computed tomography (HRCT) scans of the temporal bone are used to assess the bony erosion of the middle-ear structures whenever cholesteatoma is suspected. To study the differences in HRCT Hounsfield unit (HU) index measurements of middle-ear bony structures between an ears with and without cholesteatoma. A retrospective study of 59 patients who underwent surgery due to unilateral cholesteatoma. The HRCT HU index of the scutum, of three middle-ear ossicles, of the lateral semicircular canal (LSCC), and of the fallopian canal was measured in both ears. A comparison was made between the cholesteatoma and the non-cholesteatomatous ear (control). All measurements were conducted by an otolaryngologist. To assess the interobserver bias, 10% of the samples were randomly and independently assessed by another otolaryngologist and a neuroradiologist who were blinded. The average HU index was lower in the ear with cholesteatoma when compared with the non-cholesteatomatous ear. While the differences were statistically significant regarding the measurements of the scutum (516.02 ± 311.693 versus 855.64 ± 389.999; = 0.001), the malleus (1049.44 ± 481.765 versus 1413.47 ± 313.376; = 0.01), and the incus (498.03 ± 264.184 versus 714.25 ± 405.631; = 0.001), the differences in the measurements of the LSCC (1042.34 ± 301.066 versus 1154.53 ± 359.609; = 0.69) and of the fallopian canal (467.19 ± 221.556 versus 543.51 ± 263.573; = 0.108) were not significantly different between both groups. The stapes was immeasurable in both groups due to its small size. Hounsfield unit index measurements are a useful tool that may aid in the diagnosis of early-stage cholesteatoma.
PubMed: 35846805
DOI: 10.1055/s-0041-1736580 -
Diagnostics (Basel, Switzerland) May 2023In vivo Hounsfield Unit (HU) values have traditionally been determined using direct CT image measurements. These measurements are dependent on the window/level used to...
BACKGROUND
In vivo Hounsfield Unit (HU) values have traditionally been determined using direct CT image measurements. These measurements are dependent on the window/level used to examine the CT image and the individual conducting the fat tissue tracing.
METHODS
Using an indirect method, a new reference interval (RI) is proposed. A total of 4000 samples of fat tissues were collected from routine abdominal CT examinations. A linear regression equation was then calculated using the linear part of the cumulative frequency plot of their average values.
RESULTS
The regression function for total abdominal fat was determined to be y = 35.376*x - 123.48, and a 95% confidence RI of -123 to -89 was computed. A significant difference of 3.82 was observed between the average fat HU values of visceral and subcutaneous areas.
CONCLUSIONS
Using statistical methods and the in vivo measurements of patient data, a series of RIs were determined for fat HU that is consistent with theoretical values.
PubMed: 37296765
DOI: 10.3390/diagnostics13111913 -
Current Medical Imaging Apr 2023Deep learning-based diagnosis systems are useful to identify abnormalities in medical images with the greatly increased workload of doctors. Specifically, the rate of...
BACKGROUND
Deep learning-based diagnosis systems are useful to identify abnormalities in medical images with the greatly increased workload of doctors. Specifically, the rate of new cases and deaths from malignancies is rising for liver diseases. Early detection of liver lesions plays an extremely important role in effective treatment and gives a higher chance of survival for patients. Therefore, automatic detection and classification of common liver lesions are essential for doctors. In fact, radiologists mainly rely on Hounsfield Units to locate liver lesions but previous studies often pay little attention to this factor.
METHODS
In this paper, we propose an improved method for the automatic classification of common liver lesions based on deep learning techniques and the variation of Hounsfield Unit densities on CT images with and without contrast. Hounsfield Unit is used to locate liver lesions accurately and support data labeling for classification. We construct a multi-phase classification model developed on the deep neural networks of Faster R-CNN, R-FCN, SSD, and Mask R-CNN with the transfer learning approach.
RESULTS
The experiments are conducted on six scenarios with multi-phase CT images of common liver lesions. Experimental results show that the proposed method improves the detection and classification of liver lesions compared with recent methods because its accuracy achieves up to 97.4%.
CONCLUSION
The proposed models are very useful to assist doctors in the automatic segmentation and classification of liver lesions to solve the problem of depending on the clinician's experience in the diagnosis and treatment of liver lesions.
PubMed: 37132318
DOI: 10.2174/1573405620666230428121748 -
Neurosurgery Jul 2022Bone density has been associated with a successful fusion rate in spine surgery. Hounsfield units (HUs) have more recently been evaluated as an indirect representation...
BACKGROUND
Bone density has been associated with a successful fusion rate in spine surgery. Hounsfield units (HUs) have more recently been evaluated as an indirect representation of bone density. Low preoperative HUs may be an early indicator of global disease and chronic process and, therefore, indicative of the need for future reoperation.
OBJECTIVE
To assess preoperative HUs and their association with future adjacent segment disease requiring surgical intervention through retrospective study.
METHODS
Patients who underwent lumbar interbody fusion at a single institution between 2007 and 2016 were retrospectively reviewed. Hounsfield unit values were measured from preoperative computed tomography (CT) using sagittal images, encircling cancellous portion of the vertebral body. Patient charts were reviewed for follow-up data and adjacent-level disease development.
RESULTS
A total of 793 patients (age: 56.1 ± 13.7 years, 54.4% female) were included in this study. Twenty-two patients required surgical intervention for adjacent segment disease. Patients who underwent lumbar interbody fusion and did not subsequently require surgical intervention for adjacent-level disease were found to have a higher mean preoperative HU than patients who did require reoperation (180.7 ± 70.0 vs 148.4 ± 8.1, P = .032). Preoperative CT HU was a significant independent predictor for the requirement of adjacent-level surgery after spinal arthrodesis (odds ratio = 0.891 [0.883-0.899], P = .029).
CONCLUSION
Patients who underwent lumbar interbody fusion that did not require reoperation for adjacent-level degeneration were found to have a higher mean preoperative HU than patients who did require surgical intervention. Lower preoperative CT HU was a significant independent predictor for the requirement of adjacent-level surgery after spinal arthrodesis.
Topics: Adult; Aged; Female; Humans; Lumbar Vertebrae; Lumbosacral Region; Male; Middle Aged; Reoperation; Retrospective Studies; Spinal Fusion
PubMed: 35377348
DOI: 10.1227/neu.0000000000001949 -
British Journal of Neurosurgery Dec 2023
Topics: Humans; Bone Density; Lumbar Vertebrae; Tomography, X-Ray Computed; Retrospective Studies; Absorptiometry, Photon
PubMed: 34092164
DOI: 10.1080/02688697.2021.1933383 -
Neurosurgery Aug 2022
Topics: Humans; Lumbar Vertebrae; Lumbosacral Region; Spinal Fusion
PubMed: 35834324
DOI: 10.1227/neu.0000000000002049 -
Journal of the College of Physicians... Jan 2021The objective of the study was to determine whether Hounsfield Unit density would differentiate between cholesteatoma and other causes of opacification, such as...
The objective of the study was to determine whether Hounsfield Unit density would differentiate between cholesteatoma and other causes of opacification, such as granulation tissue in previously operated ears. Temporal bone computer tomography (CT) scans of 47 patients, who had revision mastoid surgeries, were evaluated retrospectively. A circular 5 mm2 region of interest (ROI) was placed at aditus ad antrum to measure Hounsfield Unit (HU) density. There was no statistically significant difference between cholesteatoma and non-cholesteatoma groups in terms of HU densities. Intraclass correlation coefficient test showed an intraclass correlation of 0.41 between measurements done by radiologists and otorhinolaryngologists, which showed poor reliability. Contrary to previous studies in unoperated ears, in operated ears HU density at aditus level cannot be a reliable diagnostic adjunct. Moreover, when it is considered that interrater reliability was poor between radiologists' and otolaryngologists' measurements, a need for further studies arise to solidify findings in this study. Key Words: Cholesteatoma diagnostic imaging, Middle ear surgery, Revision mastoidectomy.
Topics: Cholesteatoma, Middle Ear; Humans; Mastoid; Mastoidectomy; Reproducibility of Results; Retrospective Studies
PubMed: 33546546
DOI: 10.29271/jcpsp.2021.01.104 -
World Journal of Nephrology Nov 2014Computed tomography (CT) is widely used to examine stones in the urinary system. In addition to the size and location of the stone and the overall health of the kidney,... (Review)
Review
Computed tomography (CT) is widely used to examine stones in the urinary system. In addition to the size and location of the stone and the overall health of the kidney, CT can also assess the density of the stone in Hounsfield units (HU). The HU, or Hounsfield density, measured by CT, is related to the density of the tissue or stone. A number of studies have assessed the use of HU in urology. HUs have been used to predict the type and opacity of stones during diagnosis, and the efficacy has been assessed using methods including extracorporeal shock wave lithotripsy (ESWL), percutaneous nephrolithotomy (PCNL), ureterorenoscopic ureterolithotripsy (URSL), and medical expulsive treatment (MET). Previous studies have focused on the success rate of HU for predicting the type of stone and of ESWL treatment. Understanding the composition of the stone plays a key role in determining the most appropriate treatment modality. The most recent reports have suggested that the HU value and its variants facilitate prediction of stone composition. However, the inclusion of data regarding urine, such as pH and presence of crystals, increases the predictive accuracy. HUs, which now form part of the clinical guidelines, allow us to predict the success of ESWL; therefore, they should be taken into account when ESWL is considered as a treatment option. However, there are currently insufficient data available regarding the value of HU for assessing the efficacy of PCNL, URSL, and MET. Studies performed to date suggest that these values would make a significant contribution to the diagnosis and treatment of urinary system stones. However, more data are required to assess this further.
PubMed: 25374823
DOI: 10.5527/wjn.v3.i4.282 -
Scientific Reports Nov 2022We aimed to identify the association between Hounsfield Unit(HU)-related variables and percutaneous nephrolithotomy (PCNL) outcomes. We enrolled patients with single...
We aimed to identify the association between Hounsfield Unit(HU)-related variables and percutaneous nephrolithotomy (PCNL) outcomes. We enrolled patients with single renal stones (1-3 cm) who underwent single-tract PCNL between January 2014 and October 2019. Demographics and stone characteristics were retrospectively reviewed. Preoperative computerized tomography (CT) and follow-up CT within at least 3 months after PCNL were included in this analysis. Stone-free status was defined as residual stone measuring ≤ 2 mm within 3 months postoperatively. HU and cross-sectional area (CSA) were measured using the free-draw technique. We analyzed HU-related variables using logistic regression model for outcomes. Altogether, 188 out of 683 patients met the inclusion criteria. The stone-free rate (SFR) was 79.2%. There were no significant differences in age, sex, BMI, ASA class, laterality, pre-op shockwave lithotripsy, stone size, stone burden, skin-to-stone distance, and HU between the stone-free and remnant groups. CSA and HU/CSA in the stone-free and remnant groups were 94.5 ± 46.1 and 128.3 ± 98.5 (p = 0.043) and 10.1 ± 5.6 and 7.3 ± 3.4 (p = 0.001), respectively. Multivariate logistic regression analysis revealed that pelvis, ureteropelvic junction stones, and HU/CSA were independent predictors of SFR. HU did not affect PCNL outcomes. We believe that HU/CSA could be used for determining stone treatment plans and predicting outcomes.
Topics: Humans; Nephrolithotomy, Percutaneous; Retrospective Studies; Lithotripsy; Kidney Calculi; Tomography, X-Ray Computed; Treatment Outcome
PubMed: 36323761
DOI: 10.1038/s41598-022-23383-7