Conventional Chest Radiography Research Articles

Chest tomosynthesis: Technical principles and clinical update

Digital tomosynthesis is a radiographic technique that can produce an arbitrary number of section images of a patient from a single pass of the X-ray tube. It utilizes a conventional X-ray tube, a flat-panel detector, a computer-controlled tube mover, and special reconstruction algorithms to produce section images. While it does not have the depth resolution of computed tomography (CT), tomosynthesis provides some of the tomographic benefits of CT but at lower cost and radiation dose than CT. Compared to conventional chest radiography, chest tomosynthesis results in improved visibility of normal structures such as vessels, airway and spine. By reducing visual clutter from overlying normal anatomy, it also enhances detection of small lung nodules. This review article outlines the components of a tomosynthesis system, discusses results regarding improved lung nodule detection from the recent literature, and presents examples of nodule detection from a clinical trial in human subjects. Possible implementation strategies for use in clinical chest imaging are discussed.

Recurrent Unexplained Episodes of Facial Cyanosis and Shortness of Breath in Hunter Disease

A 12-year-old boy affected by Hunter disease (mucopolysaccaridosis type II) was referred with a history of recurrent episodes of cyanosis and shortness of breath. Physical examination disclosed the typical features of the condition, but was unremarkable for any cardiopulmonary abnormality. Careful clinical observation of the boy revealed that cyanosis was limited to his face and developed, with shortness of breath and venous cervical engorgement, within 30 seconds after elevating his arms (Figure). In 1946, H.S. Pemberton first described in a patient with a large retrosternal goiter that extension of both arms above the head was followed by facial plethora with distended neck veins and shortness of breath with stridor. The observation, which is now called positive Pemberton sign, reflects vascular and airway compromise developing when the thoracic inlet becomes obstructed by a large mass extending retrosternally. It is common in retrosternal goiter, but may also occur with lymphoma, thymoma, lung carcinoma, or aortic aneurysm. In our patient a conventional chest radiography examination disclosed 2 enlarged clavicles, a recognized finding in Hunter disease, but without any mediastinal enlargement. Typical airway concerns in Hunter disease include tongue enlargement, pharyngeal hypertrophy, supraglottic edema, and deformation of the trachea. This case indicates that in Hunter disease positional changes sometimes result in vascular and airway compromise. Thus, we propose to test the Pemberton sign in children with Hunter disease and in children with positional symptoms of the head and neck.

Pulmonary infections in HIV-positive children

Infection of the lungs and airways by viral, bacterial, fungal and protozoal agents, often producing atypical radiographic features, is common in children with human immunodeficiency virus (HIV) infection. Conventional chest radiography and chest CT remain the most useful imaging modalities for evaluation of the immunocompromised patient presenting with a suspected pulmonary infection. In this review the radiological features of acute lung infections in this population are discussed.

Performance of chest radiograph and CT scan for lung cancer screening in asbestos-exposed workers

Objectives:The aim was to compare, in a cohort of asbestos-exposed workers, the sensitivity and the specificity of low-radiation helical chest CT scan with chest radiograph for the biennial screening of...

Design and Development of a New Multi-Projection X-Ray System for Chest Imaging.

Overlapping anatomical structures may confound the detection of abnormal pathology, including lung nodules, in conventional single-projection chest radiography. To minimize this fundamental limiting factor, a dedicated digital multi-projection system for chest imaging was recently developed at the Radiology Department of Duke University. We are reporting the design of the multi-projection imaging system and its initial performance in an ongoing clinical trial. The system is capable of acquiring multiple full-field projections of the same patient along both the horizontal and vertical axes at variable speeds and acquisition frame rates. These images acquired in rapid succession from slightly different angles about the posterior-anterior (PA) orientation can be correlated to minimize the influence of overlying anatomy. The developed system has been tested for repeatability and motion blur artifacts to investigate its robustness for clinical trials. Excellent geometrical consistency was found in the tube motion, with positional errors for clinical settings within 1%. The effect of tube-motion on the image quality measured in terms of impact on the Modulation Transfer Function (MTF) was found to be minimal. The system was deemed clinic-ready and a clinical trial was subsequently launched. The flexibility of image acquisition built into the system provides a unique opportunity to easily modify it for different clinical applications, including tomosynthesis, correlation imaging (CI), and stereoscopic imaging.

Image quality in conventional chest radiography. Evaluation using the postprocessing tool Diamond View ®

The objective of this work was to evaluate the influence of the postprocessing tool Diamond View ® (Siemens AG Medical Solutions, Germany) on image quality in conventional chest radiography. Evaluation of image quality remains a challenge in conventional radiography. Based on the European Commission quality criteria we evaluated the improvement of image quality when applying the new postprocessing tool Diamond View ® (Siemens AG Medical solutions, Germany) to conventional chest radiographs. Three different readers prospectively evaluated 102 digital image pairs of chest radiographs. Statistical analysis was performed with a p value <0.05 considered as significant. Images were evaluated on basis of the modified imaging Quality Criteria by the Commission of the European Communities. Each of the 11 image quality criteria was evaluated separately using a five point classification. Statistical analysis showed an overall tendency for improved image quality for Diamond View ® (DV) for all criteria. Significant differences could be found in most of the criteria. In conclusion DV improves image quality in conventional chest radiographs.

動画対応フラットパネルディテクタによる肺機能画像診断法：肺シンチグラフィ所見との比較

Pulmonary ventilation and circulation dynamics are reflected on dynamic chest radiographs as changes in X-ray translucency,i.e., pixel values. The present study was performed to develop a pulmonary functional evaluation method based on the changes in pixel value, and to investigate the clinical usefulness of our method. Sequential chest radiographs of 20 subjects (abnormal,n=12; normal,n=8) during respiration were obtained with a dynamic flat-panel detector (FPD) system. The average pixel value in each local area was measured tracking the same area. To facilitate visual evaluation, the results were mapped on the original image using a grayscale in which small changes were shown in black and large changes were shown in white. In our clinical evaluation in comparison with a pulmonary scintigraphy, pulmonary ventilation disorder was indicated as a reduction of changes in pixel values. In many patients, there was a correlation between our result and a pulmonary scintigraphy (0.7<r, 4 cases; 0.4<r<or=0.7, 6 cases; 0.2<r<or=0.4, 1 case; 0<r<or=0.2, 1 case). The present method with real-time computer analysis is expected to be a rapid and simple method for evaluating pulmonary function and as an additional examination in conventional chest radiography.

Reading chest radiographs in the critically ill (Part II): Radiography of lung pathologies common in the ICU patient

This is part II of two series review of reading chest radiographs in the critically ill. Conventional chest radiography remains the cornerstone of day to day management of the critically ill occasionally supplemented by computed tomography or ultrasound for specific indications. In this second review we discuss radiographic findings of cardiopulmonary disorders common in the intensive care patient and suggest guidelines for interpretation based not only on imaging but also on the pathophysiology and clinical grounds.

Chronic Granulomatous Disease (CGD) Mimicking Neoplasms: A Suspected Mediastinal Teratoma Unmasking as Thymic Granulomas Due to X-linked CGD, and 2 Related Cases

Patients with chronic granulomatous disease (CGD) suffer from severe bacterial and fungal infections and deregulated inflammation, which are often associated with granuloma formation. We describe a 2-year-old boy who was seemingly healthy at the age of 1 year when a conventional chest radiograph was taken to exclude pulmonary aspiration of a piece of apple. Incidentally, a space-occupying mediastinal mass was revealed that was further evaluated by magnetic resonance imaging. Varying solid and also cystic, septated parts of the mass could be discerned and it was considered to be a teratoma. Removal of the mass by surgery was arduous because of adhesiveness to surrounding areas and led to severe complications. Unexpectedly, histopathologic examination revealed massive acute granulomatous inflammation with liquefied thymic cysts. X-linked CGD was subsequently diagnosed by a dihydrorhodamine 123 assay and sequencing of the CYBB gene (hotspot mutation c.742-743insA). This is the third example that we are aware of, where CGD granulomas were mistaken for neoplasms. The other 2 patients were initially believed to have tumors of the stomach and the urinary bladder, respectively. All patients initially received inadequate treatment. We discuss possible strategies to avoid such tragic confusions.

Left Atrial Calcifications

Left atrial wall calcifications are an extremely rare finding of unknown cause usually associated with rheumatic disease. Only a few case reports of this entity are found in the literature, mostly describing the findings on conventional chest radiography, echocardiography, and angiography. To the best of our knowledge, this is the first case documented with multislice computed tomography.

The Incomplete Fissure Sign

HomeRadiologyVol. 247, No. 2 PreviousNext Signs in ImagingThe Incomplete Fissure SignMeghan G. LubnerMeghan G. LubnerAuthor Affiliations1From the Mallinckrodt Institute of Radiology, Washington University School of Medicine, 510 S Kingshighway Blvd, Box 8131, St. Louis, MO 63110. Received May 23, 2005; revision requested July 9; revision received November 1; final version accepted January 16, 2006.Address correspondence to the author (e-mail: [email protected]).Meghan G. LubnerPublished Online:May 1 2008https://doi.org/10.1148/radiol.2472050864MoreSectionsFull textPDF ToolsImage ViewerAdd to favoritesCiteTrack CitationsPermissionsReprints ShareShare onFacebookTwitterLinked In References1 Dandy WE. Incomplete pulmonary interlobar fissure sign. Radiology 1978; 128: 21–25. Link, Google Scholar2 Hansell DM, Armstrong P, Lynch DA, McAdams HP. Pleural disorders. In: Imaging of diseases of the chest. 4th ed. St. Louis, Mo: Elsevier Mosby, 2005; 1023–1042. Google Scholar3 Proto AV. The chest radiograph: anatomic considerations. Clin Chest Med 1984; 5: 213–246. Crossref, Medline, Google Scholar4 Proto AV, Ball JB Jr. The superolateral major fissures. AJR Am J Roentgenol 1983; 140: 431–437. Crossref, Medline, Google Scholar5 Fisher MS. Significance of a visible major fissure on the frontal chest radiograph. AJR Am J Roentgenol 1981; 137: 577–580. Crossref, Medline, Google Scholar6 Proto AV, Ball JB Jr. Computed tomography of the major and minor fissures. AJR Am J Roentgenol 1983; 140: 439–448. Crossref, Medline, Google Scholar7 Hayashi K, Aziz A, Ashizawa K, Hayashi H, Nagaoki K, Otsuji H. Radiographic and CT appearances of the major fissures. RadioGraphics 2001; 21: 861–874. Link, Google Scholar8 Glazer HS, Anderson DJ, DiCroce BS, et al. Anatomy of the major fissure: evaluation with standard and thin-section CT. Radiology 1991; 180(3): 839–844. Link, Google Scholar9 Aziz A, Ashizawa K, Nagaoki K, Hayashi K. High resolution CT anatomy of the pulmonary fissures. J Thorac Imaging 2004; 19(3): 186–191. Crossref, Medline, Google Scholar10 Otsuji H, Uchida H, Maeda M, et al. Incomplete interlobar fissures: bronchovascular analysis with CT. Radiology 1993; 187: 541–546. Link, Google Scholar11 Raasch BN, Carsky EW, Lane EJ, O'Callaghan JP, Heitzman ER. Radiographic anatomy of the interlobar fissures: a study of 100 specimens. AJR Am J Roentgenol 1982; 138: 1043–1049. Crossref, Medline, Google Scholar12 Venuta F, Rendina EA, De Giacomo T, et al. Technique to reduce air leaks after pulmonary lobectomy. Eur J Cardiothorac Surg 1998; 13: 361–364. Crossref, Medline, Google ScholarArticle HistoryPublished in print: 2008 FiguresReferencesRelatedDetailsCited ByAnatomic characterization of pulmonary accessory fissures in canine cadaversPatriciaMendoza, Robson F.Giglio, ChristopherOlmo, Jeffrey R.Abbott, Richard D.Johnson, Clifford R.Berry2019 | Anatomia, Histologia, Embryologia, Vol. 48, No. 2Pulmonary Fissure Integrity and Collateral Ventilation in COPD PatientsJiantaoPu, ZhiminWang, SuichengGu, CarlFuhrman, Joseph K.Leader, XinMeng, JohnTedrow, Frank C.Sciurba, MarcoIdzko2014 | PLoS ONE, Vol. 9, No. 5Lecture Notes in Computer ScienceYoubingYin, Eric A.Hoffman, Ching-LongLin2010 | , Vol. 6362Recommended Articles Ventilation-Perfusion Scan: A Primer for Practicing RadiologistsRadioGraphics2021Volume: 41Issue: 7pp. 2047-2070Tracheobronchial Branching Abnormalities: Lobe-based Classification SchemeRadioGraphics2016Volume: 36Issue: 2pp. 358-373Imaging Course of Lung Transplantation: From Patient Selection to Postoperative ComplicationsRadioGraphics2021Volume: 41Issue: 4pp. 1043-1063Overview of Interventional Pulmonology for RadiologistsRadioGraphics2021Volume: 41Issue: 7pp. 1916-1935Imaging Manifestations of Chest TraumaRadioGraphics2021Volume: 41Issue: 5pp. 1321-1334See More RSNA Education Exhibits Mind the Gap! Accessory and Incomplete Lung Fissures: Clinical and Histopathologic ImplicationsDigital Posters2019Airway Complications: The Achilles' Heel of Lung TransplantationDigital Posters2019Breathe Sparingly: Diffuse Lung Diseases that Spare the Subpleural RegionsDigital Posters2020 RSNA Case Collection Round pneumonia RSNA Case Collection2021Pneumothorax Ex VacuoRSNA Case Collection2022Tracheal bronchusRSNA Case Collection2021 Vol. 247, No. 2 Metrics Altmetric Score PDF download

Accuracy of the physical examination in evaluating pleural effusion

A careful physical examination is a valuable and noninvasive means of assessing pleural effusion and should be routinely performed in every patient in whom this condition is suspected. Although physical examination is less accurate than ultrasonography or computed tomography in detecting a pleural effusion, the sensitivity and specificity of the different physical signs of pleural effusion may be comparable to those of conventional chest radiography.

Comparative evaluation of chest radiography, low-field MRI, the Shwachman-Kulczycki score and pulmonary function tests in patients with cystic fibrosis

The aim of this study was to investigate whether the parenchymal lung damage in patients suffering from cystic fibrosis (CF) can be equivalently quantified by the Chrispin-Norman (CN) scores determined with low-field magnetic resonance imaging (MRI) and conventional chest radiography (CXR). Both scores were correlated with pulmonary function tests (PFT) and the Shwachman-Kulczycki method (SKM). To evaluate the comparability of MRI and CXR for different states of the disease, all scores were applied to patients divided into three age groups. Seventy-three CF patients (mean SKM score: 62 +/- 8) with a median age (range) of 14 years (7-32) were included. The mean CN scores determined with both imaging methods were comparable (CXR: 12.1 +/- 4.7; MRI: 12.0 +/- 4.5) and showed high correlation (P < 0.05, R = 0.97). Only weak correlations were found between imaging, PFT, and SKM. Both imaging modalities revealed significantly more severe disease expression with age, while PFT and SKM failed to detect early signs of disease. We conclude that imaging of the lung in CF patients is capable of detecting subtle and early parenchymal destruction before lung function or clinical scoring is affected. Furthermore, low-field MRI revealed high consistency with chest radiography and may be used for a thorough follow-up while avoiding radiation exposure.

The role of imaging methods in the pre-, intra- and postoperative evaluation protocol of living donors in liver transplantation in Hungary

Az élő donoros májtranszplantáció donorjelöltjeinek komplex kivizsgálási protokollja transzplantációs centrumonként némileg eltérő lehet, de a fő komponensek világszerte megegyeznek. A protokollok anamnézisfelvételt, fizikális vizsgálatot, általános laboratóriumi teszteket, valamint specifikus alvadási, vírusszerológiai, radiológiai vizsgálatokat és pszichoszociális felmérést is tartalmaznak. A donorjelölteket képalkotó vizsgálatok szempontjából először a belszervi állapotra vonatkozó általános kivizsgálásnak vetjük alá, elsősorban hagyományos röntgen- és ultrahangvizsgálatokkal. Ezután (az előbbitől nem élesen elválaszthatóan) a májspecifikus képalkotás következik, döntően UH, CT és MR segítségével, egyrészt a májparenchyma állapotának megítélésére, másrészt a térfogat meghatározására, harmadrészt pedig az érképletek és az epeutak pontos anatómiájának ábrázolására. Invazív beavatkozásokra is szükség lehet, pl. angiográfiára, májbiopsziára. A donorműtét kezdetén rutinszerűen intraoperatív vizsgálatok is történnek: cholangiographia az eperendszer anatómiájának közvetlen feltérképezésére és ultrahangvizsgálat a vena hepatica-ágak és a vena portae-rendszer lefutásának pontosítására a reszekció vonalának meghatározásához. A donorok vizsgálatai a korai posztoperatív szakban az esetleges szövődmények felderítéséhez járulnak hozzá: speciálisan a megmaradó májállomány keringésének ellenőrzésére és a műtéti területen folyadékgyülemek kimutatására UH vagy CT történhet, a mellkas kontrollálására elsősorban hagyományos röntgenvizsgálatot végzünk. A későbbi időszakban indokolt a donorok szűrő jellegű, rendszeres követése. – Intézetünk kivizsgálási protokolljának képalkotó részét foglaljuk össze.

Value of conventional chest radiography for the detection of coronary calcifications: Comparison with MSCT

Purpose To evaluate if computed tomography (CT) coronary calcium scoring is needed after detection of coronary calcifications on conventional chest radiographs. Materials and methods One hundred and five patients (67 men; 57.2 ± 12.8 years) with suspected coronary artery disease underwent conventional chest radiography and non-enhanced, retrospectively ECG-gated multislice spiral CT (MSCT) of the heart (4 mm × 2.5 mm, 120 kV, 133 mAs eff.). Chest radiographs were assessed independently by two radiologists. Detection of coronary calcifications was compared between both methods. Sensitivity, specificity, negative and positive predictive values, median, 25% and 75% percentiles for the detection of coronary calcifications were calculated. Receiver operating characteristics (ROC) analyses were computed. Results In 90 patients, MSCT revealed coronary calcifications. The mean coronary calcium score was 526.2 (0–4784.5). On chest radiographs, coronary calcifications were correctly detected in 46 (61) patients by observer 1 (observer 2). The corresponding sensitivity was 51.1% in observer 1 and 67.8% in observer 2. Median of detected coronary calcifications was 361.9 (426.4) for observer 1 (observer 2). Corresponding 25% und 75% percentiles were 109.6 (109.6) and 798.5 (898.5). The area under the ROC curve was 0.636 for observer 1 and 0.715 for observer 2. There was no correlation between image quality and the detection of coronary calcifications on plain film radiographs. Conclusion As coronary calcifications of various extents are inconsistently detected on plain chest radiographs, CT calcium scoring may not be omitted even if coronary artery calcifications were detected on conventional chest radiographs.

Optimization of image acquisition techniques for dual‐energy imaging of the chest

Experimental and theoretical studies were conducted to determine optimal acquisition techniques for a prototype dual-energy (DE) chest imaging system. Technique factors investigated included the selection of added x-ray filtration, kVp pair, and the allocation of dose between low- and high-energy projections, with total dose equal to or less than that of a conventional chest radiograph. Optima were computed to maximize lung nodule detectability as characterized by the signal-difference-to-noise ratio (SDNR) in DE chest images. Optimal beam filtration was determined by cascaded systems analysis of DE image SDNR for filter selections across the periodic table (Z(filter) = 1-92), demonstrating the importance of differential filtration between low- and high-kVp projections and suggesting optimal high-kVp filters in the range Z(filter) = 25-50. For example, added filtration of approximately 2.1 mm Cu, approximately 1.2 mm Zr, approximately 0.7 mm Mo, and approximately 0.6 mm Ag to the high-kVp beam provided optimal (and nearly equivalent) soft-tissue SDNR. Optimal kVp pair and dose allocation were investigated using a chest phantom presenting simulated lung nodules and ribs for thin, average, and thick body habitus. Low- and high-energy techniques ranged from 60-90 kVp and 120-150 kVp, respectively, with peak soft-tissue SDNR achieved at [60/120] kVp for all patient thicknesses and all levels of imaging dose. A strong dependence on the kVp of the low-energy projection was observed. Optimal allocation of dose between low- and high-energy projections was such that approximately 30% of the total dose was delivered by the low-kVp projection, exhibiting a fairly weak dependence on kVp pair and dose. The results have guided the implementation of a prototype DE imaging system for imaging trials in early-stage lung nodule detection and diagnosis.

Case 115: Aortic Pseudoaneurysm from Penetrating Superior Vena Cava Stent1

A 35-year-old man presented with acute substernal chest pain. He described the pain as dull and constant, with occasional episodes of knifelike pain that radiated to his back and neck. These episodes were exacerbated by dialy-sis that was performed through a, right upper extremity brachiocephalic fistula. His medical history included un controlled hypertension, end-stage renal disease. and cocaine abuse. He had been hospitalized multiple times in the past year and a half for chest pain, but-no evidence of pulmonary embolism or cardiac ischemia was found. Serial transthoracic echocardiograms demonstrated nonconstrictive pericardial effusion. The present episode differed somewhat from prior episodes in that it was associated with hemodialysis Two months prior to the current episode. this patient experienced poor venous outflow during dialysis. Shunt venography depicted a tight stenosis at the junction of the right brachiocephalic vein and the superior vena cava (SVC). This area was successfully opened with a 15 X 50-mm Gianturco stent (Cook. Bloomington, Ind) and dilated to 12 mm. Subsequently, the patient was hospitalized two additional times for chest pain. At the time of the current episode, he had a blood pressure of 164/101 mm Hg, a pulse of 112 beats per minute, a respiratory rate of 18 breaths per minute, and 100% oxygen saturation on room air. Physical examination revealed a thin man in no distress; the only notable finding was engorged upper extremity veins due to the dialysis shunt. Conventional chest radiographs and computed tomographic (CT) images of the chest the chest were obtained.

Eosinophilic Lung Diseases: A Clinical, Radiologic, and Pathologic Overview

Eosinophilic lung diseases are a diverse group of pulmonary disorders associated with peripheral or tissue eosinophilia. They are classified as eosinophilic lung diseases of unknown cause (simple pulmonary eosinophilia [SPE], acute eosinophilic pneumonia [AEP], chronic eosinophilic pneumonia [CEP], idiopathic hypereosinophilic syndrome [IHS]), eosinophilic lung diseases of known cause (allergic bronchopulmonary aspergillosis [ABPA], bronchocentric granulomatosis [BG], parasitic infections, drug reactions), and eosinophilic vasculitis (allergic angiitis, granulomatosis [Churg-Strauss syndrome]). The percentages of eosinophils in peripheral blood and bronchoalveolar lavage fluid are essential parts of the evaluation. Chest computed tomography (CT) demonstrates a more characteristic pattern and distribution of parenchymal opacities than does conventional chest radiography. At CT, SPE and IHS are characterized by single or multiple nodules with a surrounding ground-glass-opacity halo, AEP mimics radiologically hydrostatic pulmonary edema, and CEP is characterized by nonsegmental airspace consolidations with peripheral predominance. ABPA manifests with bilateral central bronchiectasis with or without mucoid impaction. The CT manifestations of BG are nonspecific and consist of a focal mass or lobar consolidation with atelectasis. The most common CT findings in Churg-Strauss syndrome include sub-pleural consolidation with lobular distribution, centrilobular nodules, bronchial wall thickening, and interlobular septal thickening. The integration of clinical, radiologic, and pathologic findings facilitates the initial and differential diagnoses of various eosinophilic lung diseases.

Imaging of emphysema

Emphysema is defined as a condition of the lung characterized by abnormal, permanent enlargement of airspaces distal to the terminal bronchiole accompanied by destruction of the alveolar walls and without obvious fibrosis. It is a very common disease with high morbidity and mortality. Histopathologically, there are two types of emphysema: panlobular emphysema, typically occurring in alpha1-antitrypsin deficiency, and centrilobular emphysema, which is strongly associated with cigarette smoking. Computed tomography (CT) allows detection of emphysema with higher sensitivity than conventional chest radiography and pulmonary function tests. CT also allows quantification of emphysema and depicts associated changes and complications. The differential diagnosis of emphysema, which is characterized by the absence of clearly definable walls on CT, includes cystic lung disease, bullae, lung laceration, Langerhans cell histiocytosis, and lymphangioleiomyomatosis -which are all characterized by visible walls on CT.

Differentiating Diaphragmatic Paralysis and Eventration

Although elevation of the diaphragm can be appreciated on conventional PA and lateral chest radiography, the modality is commonly viewed as inadequate to differentiate diaphragmatic paralysis from eventration. Our objective was to qualitatively and quantitatively measure the utility of chest radiography in determining the presence or absence of diaphragmatic paralysis in patients with an elevated diaphragm. A retrospective analysis of chest radiographs in 32 patients, whom underwent fluoroscopic sniff test for elevated diaphragm, was performed. Diaphragm function was graded by a senior radiology resident, as either "paralyzed" or "non-paralyzed," based on appearance/shape of elevated hemidiaphragm on PA and lateral radiograph. The diaphragm position and shape for all patients were determined using measurements relating to skeletal structures and radius of curvature, respectively. These results were correlated with the results of the fluoroscopic sniff tests. Of 32 patients with elevated diaphragm on chest radiograph, 17 had diaphragmatic paralysis confirmed with fluoroscopic sniff test. Our results indicate that the radius of curvature or shape of the diaphragm on lateral chest radiograph is the most important factor for detection of the presence or absence of diaphragmatic paralysis. HH/APD > 0.28 suggests against paralysis. Conventional chest radiography appears to be a useful modality for assessment of the functional status of an elevated diaphragm. Based on our results, evaluation of the shape of an elevated diaphragm may preclude the need for fluoroscopic sniff test to determine diaphragmatic paralysis.