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Skin tears are classed as traumatic wounds mainly caused by shearing and frictional forces. Incidences of skin tears are noted to be significant mostly in the elderly population and those with fragile and vulnerable skin. Individuals undergoing mammography are susceptible to skin tears due to factors associated with skin breakdown such as thinning of the epidermis, use of steroids, presence of moisture, but this, when compounded with the procedure of mammography can increase the risk further. Mammography, an x-ray imaging method, which exerts adequate compression force on the breast tissue for the mammographer to obtain a high-quality image for diagnostic purposes. However, when compression force is applied during mammography resulting incidences of cutaneous skin tears can occur. Lack of and under reporting of skin tears during mammography makes it difficult to ascertain the extent of this problem and scale of its incidence. Therefore, the purpose of this narrative review is to focus on providing an overview of skin tears associated with mammography and a discussion of the current literature with regards to its incidence and diagnosis. In addition, the review will also discuss the theoretical and contextual perspective of the prevention and management strategies associated with skin tears.

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INTRODUCTION: Pressure ulcers present significant trauma to patients and are expensive to manage. In medical imaging (MI), no study has been conducted to rigorously investigate interface pressure (IP) risk on MI table surfaces. IP is defined as the pressure between human body and a supporting surface. The aims of this research were to investigate whether IP risks exist on MI table surfaces and to assess pain and comfort when lying on MI table surfaces. METHODS: A calibrated XSENSOR mat was used to measure IP for three jeopardy areas (head, sacrum, and heels) in healthy volunteers on an x-ray table surface with no mattress, an x-ray table surface with a thin radiolucent mattress, and a computed tomography table surface, after which they completed a pain and comfort questionnaire. RESULTS: The sample consisted of 26 females and 23 males aged 18-59 years (mean = 34.6; standard deviation [SD] = 10.5). Analysis of variance identified statistically significant differences in the mean IP for the jeopardy areas across the three MI table surfaces (P ≤ .001). Results also indicated high mean IP value for the head (75.9 mmHg; SD = 6.9) on the x-ray table with no mattress. Seventy percent of the volunteers found lying on the x-ray table with no mattress to be very uncomfortable. Sixty-seven percent experienced most pain whilst lying on the x-ray table with no mattress and over 81% of the pain occurred at the head. CONCLUSION: IP risk exists on x-ray tables with no mattress. This could increase the risk of developing pressure ulcers in patients accessing prolonged radiography/radiology procedures.

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PURPOSE: Planar bone scans play an important role in the staging and monitoring of malignancy and metastases. Metastases in the lumbar spine are associated with significant morbidity; therefore, accurate diagnosis is essential. Supplementary imaging after planar bone scans is often required to characterize lesions; however, this is associated with additional radiation dose. This article provides information on the comparative effective dose and effective risk from supplementary lumbar spine radiographs, low-dose computed tomography (LDCT), and diagnostic CT (DCT). METHOD: Organ dose was measured in a phantom using thermoluminescent dosimeters. Effective dose and effective risk were calculated for radiographs, LDCT, and DCT imaging of the lumbar spine. RESULTS: Radiation dose was 0.56 mSv for the anteroposterior and lateral lumbar spine radiographs, 0.80 mSv for LDCT, and 3.78 mSv for DCT. Additional imaging resulted in an increase in effective dose of 12.28%, 17.54%, and 82.89% for radiographs, LDCT, and DCT, respectively. Risk of cancer induction decreased as age increased. The difference in risk between the modalities also decreased. Males had a statistically significant higher risk than female patients (P = .023), attributed to the sensitive organs being closer to the exposed area. CONCLUSIONS: Effective dose for LDCT is comparable with radiographs of the lumbar spine. With the known benefits of image fusion, it is recommended that LDCT replace radiograph imaging for characterization of lumbar spine lesions identified on planar bone scans. DCT is associated with significantly higher effective dose than LDCT. Effective risk is also higher, and the difference is more marked in younger female patients.

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RATIONALE AND OBJECTIVES: The purpose of this study was to compare lesion-detection performance when interpreting computed tomography (CT) images that are acquired for attenuation correction when performing single photon emission computed tomography/computed tomography (SPECT/CT) myocardial perfusion studies. In the United Kingdom, there is a requirement that these images be interpreted; thus, it is necessary to understand observer performance on these images. MATERIALS AND METHODS: An anthropomorphic chest phantom with inserted spherical lesions of different sizes and contrasts was scanned on five different SPECT/CT systems using site-specific CT protocols for SPECT/CT myocardial perfusion imaging. Twenty-one observers (0-4 years of CT experience) searched 26 image slices (17 abnormal, containing 1-3 lesions, and 9 normal, containing no lesions) for each CT acquisition. The observers marked and rated perceived lesions under the free-response paradigm. Four analyses were conducted using jackknife alternative free-response receiver operating characteristic (JAFROC) analysis: (1) 20-pixel acceptance radius (AR) with all 21 readers, abbreviated to 20/ALL analysis, (2) 40-pixel AR with 21 readers (40/ALL), (3) 20-pixel AR with 14 readers experienced in CT (20/EXP), and (4) 20-pixel AR with 7 readers with no CT experience (20/NOT). The significance level of the test was set so as to conservatively control the overall probability of a type I error to <0.05. RESULTS: The mean JAFROC figure of merit (FOM) for the five CT acquisitions for the 20/ALL study were 0.602, 0.639, 0.372, 0.475, and 0.719 with a significant difference in lesion-detection performance evident between all individual treatment pairs (P < .0001) with the exception of the 1-2 pairing, which was not significant (these differed only in milliamp seconds). System 5, which had the highest performance, had the smallest slice thickness and the largest matrix size. For the other analyses, the system orderings remained unchanged, and the significance of FOM difference findings remained identical to those for 20/ALL, with one exception: for 20/EXP analysis the 1-2 difference became significant with the higher milliamp seconds superior. Improved detection performance was associated with a smaller slice thickness, increased matrix size, and, to a lesser extent, increased tube charge. CONCLUSIONS: Protocol variations for CT-based attenuation correction (AC) in SPECT/CT imaging have a measurable impact on lesion-detection performance. The results imply that z-axis resolution and matrix size had the greatest impact on lesion detection, with a weaker but detectable dependence on the product of milliamp and seconds.

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PURPOSE: Compression is necessary in mammography to improve image quality and reduce radiation burden. Maximizing the amount of breast in contact with the image receptor (IR) is important. To achieve this, for the craniocaudal projection, there is no consensus within the literature regarding how the IR should be positioned relative to the inframammary fold (IMF). No information exists within the literature to describe how pressure balancing between IR and paddle, and IR breast footprint, might be optimized. This paper describes a novel method for measuring the respective pressures applied to the breast from the IR and the paddle and a method to simultaneously measure the breast footprints on the IR and the paddle. METHODS: Using a deformable breast phantom and electronic pressure-sensitive mat, area and pressure readings were gathered from two mammography machines and four paddles at 60, 80, and 100 N with the IR positioned at -2, -1, 0, +1, and +2 cm relative to the IMF (60 combinations in total). RESULTS: Paddle and IR footprints were calculated along with a uniformity index (UI). For all four paddle/machine/pressure combinations the greatest IR footprint was achieved at IMF +2 cm. The UI indicates that the best pressure/footprint balance is achieved at IMF +1 cm. CONCLUSIONS: The authors' method appears to be suited to measuring breast footprints and pressures on IR and paddle and a human female study is planned.

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PURPOSE: To establish a simple method to determine breast readout accuracy on mammography units. METHODS: A thickness measuring device (TMD) was used in conjunction with a breast phantom. This phantom had compression characteristics similar to human female breast tissue. The phantom was compressed, and the thickness was measured using TMD and mammography unit readout. Measurements were performed on a range of screen film mammography (SFM) and full-field digital mammography (FFDM) units (8 units in total; 6 different models/manufacturers) for two different sized paddles and two different compression forces (60 and 100 N). RESULTS: The difference between machine readout and TMD for the breast area, when applying 100 N compression force, for nonflexible paddles was largest for GE Senographe DMR+ (24 cm × 30 cm paddle: +14.3%). For flexible paddles the largest difference occurred for Hologic Lorad Selenia (18 cm × 24 cm paddle: +26.0%). CONCLUSIONS: None of the units assessed were found to have perfect correlation between measured and readout thickness. TMD measures and thickness readouts were different for the duplicate units from two different models/manufacturers.

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PURPOSE: Whole-body gamma camera counting is an alternative to faecal 111In collection for quantifying disease activity in inflammatory bowel disease (IBD) but requires administration of imaging activities of 111In. The aim of this study was to explore a dedicated whole-body counter which requires 20-fold less activity than gamma camera counting. METHODS: Thirty patients with known or suspected IBD received 99mTc-granulocytes (approximately 200 MBq) and 111In-granulocytes (approximately 0.5 MBq). The 99mTc-cells were injected 45 min after the 111In-cells and immediately after a baseline 111In whole-body count. The decay-corrected count at 120 h was expressed as a fraction of baseline to give whole-body 111In retention (WBR). One patient was excluded as the injected cells were non-viable. RESULTS: Median 45-min intravascular 111In recovery was 35% in patients compared with 43% in six normal volunteers (p<0.05). WBR in normals ranged from 91% to 93% and in 11 patients with negative 99mTc imaging from 87% to 96%. Only one of 11 patients with negative imaging had WBR <90% while 11/12 patients with WBR <90% had abnormal imaging. Ten of 13 patients with Crohn's disease (CD) had abnormal imaging. The lowest WBR in these ten was 77% and six had values of >90%. There was a significant association between WBR and 99mTc image grade (Rs=0.73, p<0.002) in 16 patients without CD, but not in 13 patients with CD (Rs=0.54, p>0.05). CONCLUSION: Dedicated whole-body counting is able to quantify disease activity in IBD but may give normal values in active CD.

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