summation artifact radiologysummation artifact radiology

A true lesion of this size could not have been obscured on this view. Fig.

WebThe City of Fawn Creek is located in the State of Kansas. 9-3 to 9-6).25,26.

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Iodinated contrast media may add more detailed information about blood supply dynamics of previously identified lesions, even compared to those obtained with CEDM - Contrast-enhanced digital mammography. Chronic benign vertebral body fractures should not have this pattern of enhancement.

The possibility of separating different layers suggests a possible reduction of false negatives and false positives due to overlapping. Bone marrow signal is relatively high compared with conventional T2 spin echo sequence.

Spinal decompression and fixation were performed extending from T11 to L2, with associated artifact from the posterior metallic hardware.

A, T1WI demonstrates low signal lesion involving the entire T4 vertebral body and bowing the cortex posteriorly with cortical disruption and epidural extension. There is pathologic fracture through the L2 vertebral body with approximately 30% loss of vertebral body height. A, Off-midline sagittal T1WI demonstrates heterogeneous mildly hyper-intense lesion within the T11 and T12 vertebral bodies with soft tissue encroaching on the T1112 neural foramen, obliterating the normal perineural fat in this location. 2. The Fawn Creek time zone is Central Daylight Time which is 6 hours behind Coordinated Universal Time (UTC). Diffuse heterogeneous enhancement is present throughout the lumbar spine. Vertebral compression fractures in the absence of trauma are a common clinical problem in the elderly population.

2. Conventional mammography is limited by overlapping tissue structures, which can either mask pathology or result in summation artifacts.

Diagnosis is confirmed by bone biopsy or by demonstrating Bence Jones proteins (free light chains) in urine or monoclonal gammopathy in serum. Typical benign hemangiomas found incidentally in a 70-year-old woman imaged for back pain.

The test cant detect all cancers. A, One-view asymmetry ( arrow ) in the superior left breast on the screening MLO view. Bone marrow has high signal on this sequence, which may obscure some vertebral body lesions. Although it is the most common primary bone malignancy, multiple myeloma accounts for only 1% of all cancers.

Usually arise in vertebral body, but may involve posterior elements, Coarse trabeculae with corduroy appearance on radiograph; polka dot on CT, Fatty stroma that is bright on T1WI and T2WI, Aggressive subtype may mimic metastasis (low signal on T1, bright on T2), Differential diagnosis: Metastasis, focal fatty marrow (dark on STIR), endplate degenerative change, spinal radiation treatment (respects radiation ports). For this reason, the dose is restrained so as not to exceed the dose of a two-projections FFDM.Features common to every DBT systems are the execution mode (MLO projection), acquisition time (10-20 sec) and reconstruction time (between 40 and 180 sec), slices thickness (1 mm), display mode (single slice, or slab cine loop), chance to perform standard mammograms and FFDM/DBT real-time selection with breast compression in place.We can find, instead, great variability in the acquisitions number take-over (between 13 and 25) and the acquisition angle (between 15 and 50 ), significant features in image quality that in DBT depends on the dose and the number of projections and acquisition angle as well the number of exposures: so, if a narrow-angle with little exposure allows a fast but low-resolution 3D acquisition, a wide-angle with so many exposures provide a good resolution 3D but at a low-speed acquisition with consequent means of motion artifacts and quality deterioration of reconstructed images.

However, the latter two solutions can result in lower image contrast, although this may not be clinically significant at digital mammography due to its higher image contrast compared with screen-film mammography. Common MRI Sequences for Evaluation of Spinal Tumors. Most artifacts in radiology refer to something seen on an image that are not present in reality but appear due to a quirk of the modality itself. How do I get a copy of my grant deed in California? In children, neuroblastoma and Ewing sarcoma are the most common primary malignancies to metastasize to the spine.21,28 Metastases typically involve the vertebral body and posterior elements, and compression fractures as well as extension into the epidural space are common features. WebImaging Artifact: Soft tissue attenuation in the breast is a common artifact in myocardial perfusion imaging. As previously discussed, examples include rotation, incomplete inspiration and incorrect penetration. ADVERTISEMENT: Radiopaedia is free thanks to our supporters and advertisers. Any movement will be mapped as an area of color. In the chronic setting, the differentiation between pathologic fracture as a result of underlying malignancy and benign osteoporotic fracture is fairly simple and can be made with a high level of certainty.33,34 Marrow signal of chronic benign fractures is iso-intense to normal bone marrow on all sequences, whereas fractures associated with metastases demonstrate low signal intensity on T1-weighted sequences and high signal intensity on T2-weighted sequences.33,35 STIR images provide the greatest contrast between normal and abnormal bone marrow.33 Acute compression fractures, however, may share many of the imaging findings of metastatic lesions, and differentiation is more challenging.35,36 Features that favor acute benign osteoporotic fractures include retropulsion of a bony fragment, preservation of normal marrow signal intensity, a horizontal band-like pattern of low signal intensity on T1WI and T2WI, and the presence of other compression fractures.37,38 Features more likely to be seen in metastatic compression fractures include pedicle involvement, an associated focal paraspinal soft tissue mass or epidural mass (particularly one encasing the dural sac), convex posterior cortex, diffuse low signal intensity within the vertebral body on T1WI, and the presence of other metastases.35,3730 Some studies have suggested that a pattern of intense or heterogeneous contrast enhancement supports diagnosis of metastatic compression fracture, but this finding is inconsistent in the literature and may not be reliable.34,35,37,39 There has been increasing interest in the use of diffusion weighted imaging for differentiating benign vertebral fractures from those associated with metastases, with early results showing that reduced diffusion is highly specific for diagnosing an underlying metastatic lesion.1417 However, even this technique is not foolproof18 and either bone biopsy or follow-up imaging is often required (Table 9-5 and Figs. No account or login required to write! C, Midline T2WI shows both the vertebral body lesions and epidural component to be hyper-intense to normal marrow and soft tissue structures.

It has a sensitivity of approximately 95%, but can have false negatives if there is only marrow infiltration without cortical involvement, and is often non-specific. Bone marrow signal is heterogeneous and lower than the adjacent intervertebral discs because of diffuse infiltration with metastatic disease. Ultrasound was performed in 26 patients, and 14 (38.8%) patients had no correlated findings. Digital Breast Tomosynthesis: Initial Experience in 98 Women with Abnormal Digital Screening Mammography. Note that bone marrow signal on the T1-weighted sequence is slightly lower than that seen in examples of older patients, but is still greater than the adjacent intervertebral discs.

MRI is the most sensitive tool for detecting infiltration of bone marrow and for assessment of extension into the spinal canal and compression of the spinal cord and nerve roots.15 Patients should be cleared for MRI contraindications before undergoing imaging.

There is evidence of prior pelvic radiation with postradiation changes seen within L5 and the sacrum. Unable to process the form. While even the most advanced imaging technology doesnt allow radiologists to identify cancer with certainty, it does give them some strong clues about what deserves a closer look. B, Sagittal post-gadolinium T1-weighted fat saturated image demonstrates heterogeneous enhancement of the lesion. The lesion is hypo-intense with a hyper-intense rim. MRI of the lumbar spine was performed to rule out cord compression. MRI has been shown to be both more sensitive and specific than scintigraphy.3 Radiographs are insensitive to assess for metastatic disease, requiring at least 5070% bone destruction for detection of lesions.27,29,30 Classic radiographic signs include an absent or sclerotic pedicle, cortical destruction, and paraspinal soft tissue mass.2931 CT is more sensitive than radiographs to detect bony destruction, sclerosis, and paraspinal masses but is less sensitive than MRI and is poor for assessment of cord compression. C, Sagittal STIR image. The T6 pedicle lesion is not seen because there is no cortical destruction.

Spinal decompression and fixation were performed extending from T11 to L2, with associated artifact from the posterior metallic hardware. Artifacts can be seen depending on the view, or angle-- but they are harmless and not indicative of anything. 3 Radiographs are insensitive to assess for metastatic disease, requiring at least 5070% bone destruction for detection of lesions. 9-13 Metastatic disease with acute L4 fracture and dural sac encasement.

75-year-old female with chronic osteoporotic compression fractures. A novel approach to digital breast tomosynthesis for simultaneous acquisition of 2D and 3D images. Typical benign hemangiomas may sometimes have high signal on STIR images. D, Off-midline post-gadolinium T1-weighted fat saturated image. 4 What causes an asymmetry on a mammogram? The theoretical solutions to the problem exist: the main among them is MRI, but this is not the ideal solution because it is expensive, time-consuming, and in many cases may not be available in the same department. A, Sagittal T1WI of the thoracic spine demonstrates a focal low intensity lesion within the right T6 pedicle. What is needed instead is a solution that is: The phenomena of summation and subtraction, potentially responsible for the production of false-positive findings (FP) and for masking of true positive findings (TP), led in 1930 Alessandro Vallebona to create and implement the stratigraphy (hereinafter referred to as tomography), that is a complementary radiodiagnostic technique aimed at realizing of analytical images, namely representative just of the structures including in the pre-selected layers of the concerned region. B, Axial CT image demonstrates a focal lytic metastatic lesion within the posterior vertebral body with associated cortical disruption. Mild posterior bulging of the T9 vertebral body cortex is present with effacement of the CSF space anterior to the lower thoracic cord. D, Axial T2WI at the T12 level demonstrates the hyperintense well-circumscribed hemangioma within the left side of the vertebral body. In conclusion, DBT is definitely able to improve dense breasts imaging using a two- projections mammography dose, preserving high spatial resolution and quick workflow typical of FFDM.

CT provides useful diagnostic information, characterizing cortical destruction, lesion margins, and tumor matrix, and may demonstrate pathognomonic features for specific lesions. C, Sagittal STIR.

The phenomena of summation and subtraction, potentially responsible for the production of false-positive findings (FP) and for masking of true positive findings (TP), led in 1930 Alessandro Vallebona to create and implement the stratigraphy (hereinafter referred to as tomography ), that is a complementary radiodiagnostic technique aimed

B, On the sagittal T2WI, the lesion is heterogeneous but predominantly hyper-intense.

clothing, external cardiac monitor leads, body parts of carer, etc. If you continue to use this site we will assume that you are happy with it. X-ray artifacts can present in a variety of ways including abnormal shadows noted on a radiograph or degraded image quality, and have been produced by artificial means from hardware failure, operator error and software (post-processing) artifacts. Table 9-1 Common MRI Sequences for Evaluation of Spinal Tumors. Reconstruction algorithm in V-DBT system takes full advantage of any information provided in the 0 projection, which is basically a standard mammogram characterized by high contrast, which also provides valuable information for the microcalcifications visualization and their identification by 3D CAD, not yet available, but certainly among the future developments related to DBT. Although direct digital mammography (FFDM - Full Field Digital Mammography) has improved the sensitivity of the method, especially in dense breasts, the number of false negatives (FN) is still high, largely due to the presence of dense tissue that may affect lesions conspicuity: the mammogram is, in fact, a summation image" that displays on a single plane a more or less visible representation of any structure crossed by the X-ray beam between input and output surfaces. (2012) American Journal of Roentgenology.

d) simple (a new method would require technicians and radiologists to learn new procedures for examination and assessment).

Mild central wedging of the vertebral body is noted with buckling of the inferior vertebral body endplate.

C, The two lesions are dark on the STIR image, blending in with normal bone marrow.

(1997) Radiology. This appearance should not be confused with intradural metastases.

Its still ongoing a study comparing the clinical performance of FFDM in two projections (CC + MLO) and those of DBT in a single projection (MLO) in compliance with dose constraint. Normal bone marrow is low signal with linear high signal present as a result of the basivertebral venous plexus. At the time the article was last revised Andrew Murphy had A skin lesion produced or perpetuated by self-inflicted action, as in

Christina M. Shafer, Ehsan Samei, Joseph Y.

What causes a summation artifact on a mammography? A, Sagittal CT image demonstrates diffuse mottled appearance of the spine because of numerous lytic lesions.

Summation artifact (superimposition of breast tissue): The DBT movies obtained at the diagnostic evaluation best demonstrated that this asymmetry is created A discussion of contraindications is beyond the scope of this chapter, but a useful reference is Shellocks Reference Manual for Magnetic Resonance Safety, Implants, and Devices.6 Of note, metallic implants for spinal fusion are not a contraindication, but may create magnetic susceptibility artifacts, which are greatest on fat saturated images and gradient echo (GRE) sequences and are minimized with the fast spin echo (FSE) technique.7 When assessing the spine, sagittal spin echo T1-weight images (T1WI) and T2-weighted images (T2WI) with axial GRE or FSE T2WI images are part of our routine protocol. Summation artifact is caused by overlapping fibroglandular breast tissue and will be pliable and disperse on spot compression images, revealing no suspicious features ( Fig 3 ). D, Sagittal post-gadolinium T1-weighted fat saturated image. ADVERTISEMENT: Supporters see fewer/no ads, Please Note: You can also scroll through stacks with your mouse wheel or the keyboard arrow keys. The difference between best practices in hospital and forensic radiology may explain how this occurred. Fig.

Summation Artifacts are harmless objects photographically superimposed to resemble cancerous lesions. WebMost asymmetries are benign or caused by summation artifacts because of typical breast tissue superimposition during mammography, but an asymmetry can indicate breast cancer. Artifact is also used to describe findings that are due to things outside the patient that may obscure or distort the image, e.g.

Enter a Melbet promo code and get a generous bonus, An Insight into Coupons and a Secret Bonus, Organic Hacks to Tweak Audio Recording for Videos Production, Bring Back Life to Your Graphic Images- Used Best Graphic Design Software, New Google Update and Future of Interstitial Ads. CSF is bright.

Pathological vs. Benign Compression Fractures. Summation Artifact. Normal horizontal linear enhancement can be seen centrally within the vertebral bodies as a result of the basivertebral venous plexus. This sequence is most sensitive for demonstrating the high signal caused by edema from the acute fractures.

Fig.

9-6 Aggressive hemangioma with a large epidural component.

The acute fracture enhances, which is a non-specific finding and could be seen with both benign and pathological fractures. B, Sagittal T2WI demonstrates high signal within this lesion confirming the diagnosis of hemangioma.

MRI of the thoracic spine demonstrates solitary T4 metastasis.

Artifacts due to a nonuniform magnetic field are particularly noticeable at air-tissue interfaces but may also be caused by incomplete fat

More recent studies indicate about 30% increased DBT sensitivity and specificity compared to FFDM with a recalls reduction in screening by approximately 40%. However, those without cortical disruption are subtle and easy to overlook.

D, Axial post-gadolinium T1-weighted fat saturated image at the T9 level. A, Sagittal T1-weighted spin echo image of the lumbar spine. Subtle anterior cortical buckling is noted. The purpose of this article is to review the definition of developing asymmetry, describe the multimodality diagnostic tools available to the radiologist for evaluation of this challenging entity, and review the various causes, both benign and malignant.

Numerous enhancing lesions are evident throughout the vertebral bodies and within the posterior elements at multiple levels. Fig. Metastases are the most common malignancy to affect the spinal column. Discussion Forum Board of Fawn Creek Montgomery County Kansas, US. Multiple myeloma is a multifocal malignant proliferation of monoclonal plasma cells that occurs most commonly in men older than 60 years. 9-7 to 9-10). However, additional high signal lesions are evident within the L3, L5, and S1 vertebrae, consistent with metastases that could not be seen on the conventional T1- and T2-weighted sequences. E, Axial T2-weighted FSE image at the T6 level. In V-DBT 13 images are taken through the 40 tube oscillation movement, the central one with 50% of the total dose delivered (the same as that required for a single mammography projection), and the remaining 50% unevenly split among the twelve remaining acquisitions.

The L5 vertebral body and sacrum are uniformly high in signal because of prior radiation treatment to this area. 9-15 and 9-16). 9-4 Typical benign hemangiomas may sometimes have high signal on STIR images.

Motion artifacts are caused primarily by unavoidable globe motion during imaging. Although clinical history is helpful, up to one-third of fractures in patients with known primary malignancy are benign, and approximately one-quarter of fractures in apparently osteopenic patients are caused by metastases.31 Diagnosis of an underlying lesion is important because it influences clinical staging, treatment planning, and prognosis for the patient.

I pretty much do not have any traffic, views or calls now. A, Midline sagittal T1WI of the thoracic spine demonstrates a heterogeneous hyper-intense lesion involving almost the entire T9 vertebral body. TOPIX, Facebook Group, Craigslist, City-Data Replacement (Alternative). The FSE technique is helpful in minimizing artifact from the metallic spinal hardware. WebWe describe 2 concepts of radiation physics-poor x-ray penetration and summation artifact-which can cause a radiopaque object such as a bullet to seem much less so. E, Sagittal post-gadolinium T1-weighted fat saturated image. Fig. The appearance is therefore consistent with summation artifact.

B, Sagittal T2-weighted FSE image. Aggressive T9 hemangioma with epidural and paravertebral extension and mild wedging of the vertebral body inferior endplate. I, Axial CT image at the T6 level. The fractures extending through the T12 and L1 vertebral bodies are more readily appreciated as a result of high signal from associated edema. While striving to detect

This is a T2-weighted fat saturated sequence.

The bone marrow is relatively homogeneous and is hyper-intense relative to the adjacent intervertebral discs. B, Sagittal T2-weighted sequence.

The vertebral body components enhance heterogeneously and slightly less avidly.

clothing, external cardiac monitor leads, body parts of carer, etc. No other lesions are identified. A, Sagittal T1WI of the lumbar spine demonstrates low signal lesions within the T12, L2, and L3 vertebral bodies. WebA developing asymmetry is a focal asymmetry that is new or increased in conspicuity compared with the previous mammogram. Until it will be demonstrated at least the clinical non-inferiority of DBT compared to FFDM, it is not reasonable a dose increasing in DBT. A, Sagittal T1WI of the lumbar spine demonstrates round, relatively well-circumscribed hyperintense lesions within the T12 and L2 vertebral bodies. Check for errors and try again. Respiratory motion, often uncontrollable in the elderly, may cause great difficulty in the use of color Doppler ultrasonography.

Under the BI-RADS lexicon 5, there are four types of asymmetries: The most common cause for an asymmetry on screening mammography is superimposition of normal breast tissue (summation artifact) 6. Fluorodeoxyglucose (FDG) PET is gradually assuming an increasingly important role in following response to treatment44 (Table 9-6 and Figs. Figure 2a.

L T Niklason, B T Christian, L E Niklason, et al. 9-1 Normal appearance of bone marrow on common imaging sequences. The summation artifact was the etiology of developing asymmetry in 11 (30.5%) patients.

The most common cause for an asymmetry on screening mammography is superimposition of normal breast tissue (summation artifact) 6.

It is thus exceeded one of the limits of two-dimensional imaging, which is the masking of lesions caused by the superimposition of normal structures.

The vertebral body metastases enhance. Unlike the previous example in Figure 9-3, high signal is seen within the L2 hemangioma on STIR. WebSummation artifacts accounted for more one-view-only findings from FFDM (1067/1592; 67.0%) than FFDM-DBT (190/354; 53.7%) ( p < 0.0001). Click to share on Twitter (Opens in new window), Click to share on Facebook (Opens in new window), Click to share on Google+ (Opens in new window).

2011;21 (6): 1207-13.

Digital breast tomosynthesis (DBT)is an imaging technique that allows a volumetric reconstruction of the whole breast from a finite number of low-dose two-dimensional projections obtained by different X-ray tube angles, with a geometric principle very similar to that applied in stratigraphic technique. MRI has been shown to be both more sensitive and specific than scintigraphy.

The heterogeneous low signal within the vertebral body could be a result of edema rather than metastatic infiltration.

Artifact is also used to describe findings that are due to things outside the patient that may obscure or distort the image, e.g. Eur Radiol. MRI vs. CT visualization of metastatic disease. Digital breast tomosynthesis. Diagnosis is confirmed by bone biopsy or by demonstrating Bence Jones proteins (free light chains) in urine or monoclonal gammopathy in serum. 24-year-old female with acute traumatic compression fractures. C, Sagittal STIR image.

The remainder of the visualized bone marrow is normal for a patient of this age. This chapter begins with a brief discussion of imaging modalities and techniques for imaging vertebral lesions. B, Sagittal T2WI also demonstrates uniform normal signal throughout the spine as is expected for chronic benign compression fractures. a) affordable (an add-on on the price of a mammogram), b) fast (the radiologist must be able to perform the complementary examination immediately after evaluating the mammographic images).

Find directions to Fawn Creek, browse local businesses, landmarks, get current traffic estimates, road conditions, and more. Other radiographic artifact includes clothing or jewellery not removed. MRI of the thoracic spine demonstrates solitary T4 metastasis. Does It Matter? C, Sagittal T1-weighted post-gadolinium fat saturated image. A, Sagittal T1WI.

Reference article, Radiopaedia.org (Accessed on 08 Apr 2023) https://doi.org/10.53347/rID-15235, {"containerId":"expandableQuestionsContainer","displayRelatedArticles":true,"displayNextQuestion":true,"displaySkipQuestion":true,"articleId":15235,"questionManager":null,"mcqUrl":"https://radiopaedia.org/articles/digital-breast-tomosynthesis/questions/1665?lang=us"}. Aggressive T9 hemangioma with epidural and paravertebral extension and mild wedging of the vertebral body inferior endplate. Confirming a developing asymmetry with spot compression views. What causes an artifact on an ultrasound of the breast? Summation artifact is caused by overlapping fibroglandular breast tissue and will be pliable and disperse on spot compression images, revealing no suspicious features ( Fig 3 ). 5 What causes an artifact on an ultrasound of the breast? WebAAPM: The American Association of Physicists in Medicine This is spurious or unclear appearance of an anatomical structure due to radiographic technique. Fig. D, Sagittal post-gadolinium T1WI.

Bone marrow signal is uniform throughout the spine and is high signal relative to the intervertebral discs.

November 9, 2011 - 8:21am. This patient has diffuse metastatic disease throughout the spine.

The CT appearance of a low attenuation lesion with coarse trabeculae throughout (giving a polka-dot appearance in cross-section) is diagnostic.22 MRI demonstrates the fatty stroma, which is bright on T1WI and iso-intense to hyperintense to marrow on T2WI, with avid enhancement after administration of gadolinium.23 Bone scan is typically normal.24 An aggressive subtype of hemangioma is recognized that tends to be associated more commonly with epidural extension and pathological fracture. In the FFDM cohort, 28 one-view-only findings proved malignant (24 invasive ductal carcinoma [IDC], one invasive lobular carcinoma [ILC], and three ductal carcinoma in situ [DCIS]). SE, spin echo; FSE, fast spin echo; STIR, short tau inversion recovery. 9-3 Typical benign hemangiomas found incidentally in a 70-year-old woman imaged for back pain. In DBT the X-ray tube makes an arc, during which a series of images are acquired, each of which is delivered a dose equal to a fraction of that provided in a standard mammogram.

It may artifactually affect the depiction of activity in t Read More. Case 2: stereotactic tomosynthesis biospy of malignant breast calcifications, View Stefano Pacifici's current disclosures, see full revision history and disclosures, inferomedial superolateral oblique projection, breast ultrasound features: benign vs malignant. A further advantage of DBT is given by the lack of need for operator training (the breast is positioned just like conventional mammography in MLO and/or CC projection) and for the radiologist (as he continues to perform diagnosis from images with mammograms features). WebSummation artifact occurs when normal fibroglandular tissues superimpose (and simulate an abnormality) in a particular projection but are proven to represent normal tissues in other projections. Cerebrospinal fluid (CSF) is dark.

Detection and diagnosis of asymmetries is challenging because they often are subtle and appear similar to typical fibroglandular tissue in the breast.

D, Sagittal post-gadolinium T1-weighted fat saturated image. F, Axial post-gadolinium T1-weighted fat saturated image at the T12 level. C, Sagittal STIR image. Your rating: none, Average: 3.3 (26 votes), XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX" scrolling="no" frameborder="0" style="border:none; overflow:hidden; width:80px; height:20px; margin:0 5px 0 0;" allowTransparency="true">.

205 (2): 399-406.

At the time the article was created Stefano Pacifici had no recorded disclosures. B, T2WI of the lumbar spine demonstrates the acute fracture but does not demonstrate specific features of benign vs. pathological fracture. Fig.

The enlarged right hilar lymph nodes are demonstrated on this image. 3.

Fig.