Medical devices of the chest

Chest Intensive Care Unit Imaging: Pearls and Pitfalls

Imaging plays a major role in the care of the intensive care unit (ICU) patients. An understanding of the monitoring devices is essential for the interpretation of imaging studies. An awareness of their expected locations aids in identifying complications in a timely manner. This review describes the imaging of ICU monitoring and support catheters, tubes, and pulmonary and cardiac devices, some more commonly encountered and others that have been introduced into clinical patient care more recently. Special focus will be placed on chest radiography and potential pitfalls encountered.

Artificial Intelligence to Assess Tracheal Tubes and Central Venous Catheters in Chest Radiographs Using an Algorithmic Approach With Adjustable Positioning Definitions

PURPOSE

To develop and validate an artificial intelligence algorithm for the positioning assessment of tracheal tubes (TTs) and central venous catheters (CVCs) in supine chest radiographs (SCXRs) by using an algorithm approach allowing for adjustable definitions of intended device positioning.

MATERIALS AND METHODS

Positioning quality of CVCs and TTs is evaluated by spatially correlating the respective tip positions with anatomical structures. For CVC analysis, a configurable region of interest is defined to approximate the expected region of well-positioned CVC tips from segmentations of anatomical landmarks. The CVC/TT information is estimated by introducing a new multitask neural network architecture for jointly performing type/existence classification, course segmentation, and tip detection. Validation data consisted of 589 SCXRs that have been radiologically annotated for inserted TTs/CVCs, including an experts' categorical positioning assessment (reading 1). In-image positions of algorithm-detected TT/CVC tips could be corrected using a validation software tool (reading 2) that finally allowed for localization accuracy quantification. Algorithmic detection of images with misplaced devices (reading 1 as reference standard) was quantified by receiver operating characteristics.

RESULTS

Supine chest radiographs were correctly classified according to inserted TTs/CVCs in 100%/98% of the cases, thereby with high accuracy in also spatially localizing the medical device tips: corrections less than 3 mm in >86% (TTs) and 77% (CVCs) of the cases. Chest radiographs with malpositioned devices were detected with area under the curves of >0.98 (TTs), >0.96 (CVCs with accidental vessel turnover), and >0.93 (also suboptimal CVC insertion length considered). The receiver operating characteristics limitations regarding CVC assessment were mainly caused by limitations of the applied CXR position definitions (region of interest derived from anatomical landmarks), not by algorithmic spatial detection inaccuracies.

CONCLUSIONS

The TT and CVC tips were accurately localized in SCXRs by the presented algorithms, but triaging applications for CVC positioning assessment still suffer from the vague definition of optimal CXR positioning. Our algorithm, however, allows for an adjustment of these criteria, theoretically enabling them to meet user-specific or patient subgroups requirements. Besides CVC tip analysis, future work should also include specific course analysis for accidental vessel turnover detection.

Pacemaker in patients undergoing mammography: A limitation for breast cancer diagnosis?

INTRODUCTION

A pacemaker may affect the utility of a mammogram in several ways. The aim of this study is to summarize our institution's experience with mammograms among patients with a cardiac pacemaker, focusing on the diagnostic workup among patients with a newly diagnosed ipsilateral breast cancer.

METHODS

A retrospective search of all mammography reports between January 2011 and April 2021 was conducted for identifying cases of patients with a pacemaker. Demographic and clinical characteristics as well as mammography-derived quality parameters and findings were categorized and statistically compared.

RESULTS

The incidence of pacemaker concurrence in mammographic examination, although apparently slightly under-documented, accounted for 0.33% of cases. Population mean age was 71.7 years, and most patients (79%) had a left-sided pacemaker. The pacemaker was much more likely to be projected on the medio-lateral-oblique (96%) than on the cranio-caudal view (10%), on the axilla rather than the breast, and on the retro-pectoral rather than the pre-pectoral region (P < 0.001 for all). Compression force decreased by up to 23.0% (P < 0.001) and breast thickness increased by up to 9.5% (P < 0.001) for the ipsilateral vs. the contralateral side. Among 11 patients with newly diagnosed ipsilateral breast cancer, the pacemaker partially projected on the tumour region in two cases, and significantly obscured the tumour in another two.

CONCLUSION

Although rare, the coexistence of a pacemaker in patients undergoing mammography is associated with reduced image quality due to suboptimal breast visualization and reduced compression, and as a result, this may eventually lead to decreased diagnostic efficacy.

Chest X-ray Interpretation: Detecting Devices and Device-Related Complications

This short review has the aim of helping the radiologist to identify medical devices when interpreting a chest X-ray, as well as looking for their most commonly detectable complications. Nowadays, many different medical devices are used, often together, especially in critical patients. It is important for the radiologist to know what to look for and to remember the technical factors that need to be considered when checking each device's positioning.

Detecting Endotracheal Tube and Carina on Portable Supine Chest Radiographs Using One-Stage Detector with a Coarse-to-Fine Attention

In intensive care units (ICUs), after endotracheal intubation, the position of the endotracheal tube (ETT) should be checked to avoid complications. The malposition can be detected by the distance between the ETT tip and the Carina (ETT–Carina distance). However, it struggles with a limited performance for two major problems, i.e., occlusion by external machine, and the posture and machine of taking chest radiographs. While previous studies addressed these problems, they always suffered from the requirements of manual intervention. Therefore, the purpose of this paper is to locate the ETT tip and the Carina more accurately for detecting the malposition without manual intervention. The proposed architecture is composed of FCOS: Fully Convolutional One-Stage Object Detection, an attention mechanism named Coarse-to-Fine Attention (CTFA), and a segmentation branch. Moreover, a post-process algorithm is adopted to select the final location of the ETT tip and the Carina. Three metrics were used to evaluate the performance of the proposed method. With the dataset provided by National Cheng Kung University Hospital, the accuracy of the malposition detected by the proposed method achieves 88.82% and the ETT–Carina distance errors are less than 5.333±6.240 mm.

Deep Learning on Chest X-ray Images to Detect and Evaluate Pneumonia Cases at the Era of COVID-19

Coronavirus disease 2019 (COVID-19) is an infectious disease with first symptoms similar to the flu. COVID-19 appeared first in China and very quickly spreads to the rest of the world, causing then the 2019-20 coronavirus pandemic. In many cases, this disease causes pneumonia. Since pulmonary infections can be observed through radiography images, this paper investigates deep learning methods for automatically analyzing query chest X-ray images with the hope to bring precision tools to health professionals towards screening the COVID-19 and diagnosing confirmed patients. In this context, training datasets, deep learning architectures and analysis strategies have been experimented from publicly open sets of chest X-ray images. Tailored deep learning models are proposed to detect pneumonia infection cases, notably viral cases. It is assumed that viral pneumonia cases detected during an epidemic COVID-19 context have a high probability to presume COVID-19 infections. Moreover, easy-to-apply health indicators are proposed for estimating infection status and predicting patient status from the detected pneumonia cases. Experimental results show possibilities of training deep learning models over publicly open sets of chest X-ray images towards screening viral pneumonia. Chest X-ray test images of COVID-19 infected patients are successfully diagnosed through detection models retained for their performances. The efficiency of proposed health indicators is highlighted through simulated scenarios of patients presenting infections and health problems by combining real and synthetic health data.

Uncommon Iatrogenic Devices Seen on Chest Radiographs

Chest radiograph (CXR) is the most common imaging performed for both inpatients and outpatients. With advances in medicine and technology, newer devices/prosthesis are being used in the treatment of cardiothoracic conditions. Some of these are common while others are seen only in a handful of cases, especially in patients being treated or referred from tertiary care centers. It is important to know about these devices, their functionality, and radiographic appearances. Many of these devices also help us in understanding the clinical condition of the patient, as some are only used in unstable patients. Newer methods of life support are now available in intensive care units and these also can be seen on CXRs. In this review, we present various iatrogenic devices that we come across on a CXR and highlight important features to determine their correct placement and potential complications. The review looks at cardiac temporary and permanent pacing devices, cardiac interventional devices used to treat congenital heart disease, newer cardiac monitoring devices, and unusual surgical devices that one may come across on a CXR. We also suggest a stepwise algorithm to assess these devices on a CXR.

Medical and surgical devices in the emergency and trauma patient: what the radiologist should know, and how they can add value

A variety of different external and internal medical devices are used in the acute setting to maintain life support and manage severely injured and unstable trauma or emergency patients. These devices are inserted into the acutely ill patient with the specific purpose of improving outcome, but misplacement can cause additional morbidity and mortality. Consequently, meaningful interpretation of the position of devices can affect acute management. Some devices such as nasopharyngeal, nasogastric and endotracheal tubes and chest and surgical drains are well known to most clinicians, however, little formal training exists for radiologists in composing their report on the imaging of these devices. The novice radiologist often relies on tips and phrases handed down in an aural tradition or resorts to phrases such as: "position as shown". Furthermore, radiologists with limited experience in trauma might not be familiar with the radiological appearance of other more specific devices. This review will focus on the most common medical devices used in acute trauma patients, indications, radiological appearance and their correct and suboptimal positioning.

The mammographic appearance of the BioMonitor implantable loop recorder

The imaging appearance of implantable loop recorders (ILR's) have been described in literature (Steinberger and Margolies, 2017; Mayo and Leung, 2017; Tsau and Berger, 2004)^1-3; however, the mammographic appearance of the BioMonitor ILR produced by BIOTRONIK has not been described. It is important for radiologists interpreting breast imaging to become familiar with the appearance of different implantable cardiac devices on mammograms in order to create accurate reports and adjust imaging protocols to improve imaging quality and lessen patient discomfort as needed.

Robust segmentation of lung in chest x-ray: applications in analysis of acute respiratory distress syndrome

Background

This study outlines an image processing algorithm for accurate and consistent lung segmentation in chest radiographs of critically ill adults and children typically obscured by medical equipment. In particular, this work focuses on applications in analysis of acute respiratory distress syndrome – a critical illness with a mortality rate of 40% that affects 200,000 patients in the United States and 3 million globally each year.

Methods

Chest radiographs were obtained from critically ill adults (n = 100), adults diagnosed with acute respiratory distress syndrome (ARDS) (n = 25), and children (n = 100) hospitalized at Michigan Medicine. Physicians annotated the lung field of each radiograph to establish the ground truth. A Total Variation-based Active Contour (TVAC) lung segmentation algorithm was developed and compared to multiple state-of-the-art methods including a deep learning model (U-Net), a random walker algorithm, and an active spline model, using the Sørensen–Dice coefficient to measure segmentation accuracy.

Results

The TVAC algorithm accurately segmented lung fields in all patients in the study. For the adult cohort, an averaged Dice coefficient of 0.86 ±0.04 (min: 0.76) was reported for TVAC, 0.89 ±0.12 (min: 0.01) for U-Net, 0.74 ±0.19 (min: 0.15) for the random walker algorithm, and 0.64 ±0.17 (min: 0.20) for the active spline model. For the pediatric cohort, a Dice coefficient of 0.85 ±0.04 (min: 0.75) was reported for TVAC, 0.87 ±0.09 (min: 0.56) for U-Net, 0.67 ±0.18 (min: 0.18) for the random walker algorithm, and 0.61 ±0.18 (min: 0.18) for the active spline model.

Conclusion

The proposed algorithm demonstrates the most consistent performance of all segmentation methods tested. These results suggest that TVAC can accurately identify lung fields in chest radiographs in critically ill adults and children.

Chest radiographs of cardiac devices (Part 1): Lines, tubes, non-cardiac medical devices and materials

Chest radiographs (CXRs) are the most common imaging investigations undertaken because of their value in evaluating the cardiorespiratory system. They play a vital role in intensive care units for evaluating the critically ill. It is therefore very common for the radiologist to encounter tubes, lines, medical devices and materials on a daily basis. It is important for the interpreting radiologist not only to identify these iatrogenic objects, but also to look for their accurate placement as well as for any complications related to their placement, which may be seen either on the immediate post-procedural CXR or on a follow-up CXR. In this article, we discussed and illustrated the routinely encountered tubes and lines that one may see on a CXR as well as some of their complications. In addition, we also provide a brief overview of other important non-cardiac medical devices and materials that may be seen on CXRs.

Back to Fundamentals: Radiographic Evaluation of Thoracic Lines and Tubes in Children

OBJECTIVE. The purpose of this article is to provide an up-to-date review of the radiographic appearance of the most commonly used thoracic lines and tubes in pediatric patients in daily clinical practice. CONCLUSION. Thoracic support lines and tubes are frequently used in children receiving hospital care. Evaluation of these devices is a fundamental skill in radiology. Many different devices are currently used, and new devices are regularly introduced. It is essential for radiologists to maintain a clear understanding of all devices currently in use.

Imaging Properties of 3D Printed Materials: Multi-Energy CT of Filament Polymers

Clinical applications of 3D printing are increasingly commonplace, likewise the frequency of inclusion of 3D printed objects on imaging studies. Although there is a general familiarity with the imaging appearance of traditional materials comprising common surgical hardware and medical devices, comparatively less is known regarding the appearance of available 3D printing materials in the consumer market. This work detailing the CT appearance of a selected number of common filament polymer classes is an initial effort to catalog these data, to provide for accurate interpretation of imaging studies incidentally or intentionally including fabricated objects. Furthermore, this information can inform the design of image-realistic tissue-mimicking phantoms for a variety of applications, with clear candidate material analogs for bone, soft tissue, water, and fat attenuation.

Pacemakers in MRI for the Neuroradiologist

Cardiac implantable electronic devices are frequently encountered in clinical practice in patients being screened for MR imaging examinations. Traditionally, the presence of these devices has been considered a contraindication to undergoing MR imaging. Growing evidence suggests that most of these patients can safely undergo an MR imaging examination if certain conditions are met. This document will review the relevant cardiac implantable electronic devices encountered in practice today, the background physics/technical factors related to scanning these devices, the multidisciplinary screening protocol used at our institution for scanning patients with implantable cardiac devices, and our experience in safely performing these examinations since 2010.

Evaluation of medical devices in thoracic radiograms in intensive care unit - time to pay attention!

Objective

To identify and evaluate the correct positioning of the most commonly used medical devices as visualized in thoracic radiograms of patients in the intensive care unit of our center.

Methods

A literature search was conducted for the criteria used to evaluate the correct positioning of medical devices on thoracic radiograms. All the thoracic radiograms performed in the intensive care unit of our center over an 18-month period were analyzed. All admissions in which at least one thoracic radiogram was performed in the intensive care unit and in which at least one medical device was identifiable in the thoracic radiogram were included. One radiogram per admission was selected for analysis. The radiograms were evaluated by an independent observer.

Results

Out of the 2,312 thoracic radiograms analyzed, 568 were included in this study. Several medical devices were identified, including monitoring leads, endotracheal and tracheostomy tubes, central venous catheters, pacemakers and prosthetic cardiac valves. Of the central venous catheters that were identified, 33.6% of the subclavian and 23.8% of the jugular were malpositioned. Of the endotracheal tubes, 19.9% were malpositioned, while all the tracheostomy tubes were correctly positioned.

Conclusion

Malpositioning of central venous catheters and endotracheal tubes is frequently identified in radiograms of patients in an intensive care unit. This is relevant because malpositioned devices may be related to adverse events. In future studies, an association between malpositioning and adverse events should be investigated.

Radiology of cardiac devices and their complications

This article familiarizes the reader with several different cardiac devices including pacemakers and implantable cardioverter defibrillators, intra-aortic balloon pumps, ventricular assist devices, valve replacements and repairs, shunt-occluding devices and passive constraint devices. Many cardiac devices are routinely encountered in clinical practice. Other devices are in the early stages of development, but circumstances suggest that they too will become commonly found. The radiologist must be familiar with these devices and their complications.

Diagnostic errors with inserted tubes, lines and catheters in children

BACKGROUND

Tubes and catheters are frequently used in the care of hospitalized children. Yet little is known about errors in diagnosis in commonly implanted devices in a pediatric population.

OBJECTIVE

The purpose of this study was to determine the frequency and range of diagnostic errors with inserted devices in a pediatric population.

MATERIALS AND METHODS

During a 9-year period 142,041 cases were reviewed as part of our ongoing quality-assurance process. Of 4,084 disagreements in diagnosis encountered, 50 cases with diagnostic errors related to endovascular catheters, gastrointestinal, genitourinary and neurosurgical tubes, and pacemaker wires were identified and retrospectively reviewed. Diagnostic error was defined as a diagnosis that was unintentionally delayed, wrong or missed. These errors were classified as perceptual, cognitive, system-related or unavoidable and were graded according to potential clinical impact using a scale from 1 to 4, with 4 being the most serious.

RESULTS

Device-related diagnostic errors accounted for 1.2% of all discrepancies identified and 10% of errors potentially leading to a change in therapy. Seventeen of the 50 diagnostic errors were related to vascular catheters (34%), including wrong anatomical location of catheter tip (12) and missed catheter fracture or migration (5). Twenty-seven errors (54%) were related to non-vascular catheters and involved enteric tube location (15), ventricular drainage catheters (7), endotracheal tubes (3) and genitourinary catheters (2). Six additional errors involved a vascular stent, endovascular cuff, needle, chest tube and epicardial wire placement (2).

CONCLUSION

Device-related diagnostic errors are not frequent in complex pediatric patients. However, they can have a clinically significant impact on patient outcomes and management. High-risk situations include altered patient anatomy, poor or limited image quality, inconspicuous lines and incomplete review of prior studies.

Chest radiography in the ICU: Part 2, Evaluation of cardiovascular lines and other devices

OBJECTIVE

In this pictorial essay, we discuss and illustrate normal and aberrant positioning of the cardiovascular support and monitoring devices frequently used in critically ill patients, including central venous catheters, pulmonary artery catheters, left atrial catheters, transvenous pacemakers, automatic implantable cardioverter defibrillators, intraaortic counterpulsation balloon pump, and ventricular assist devices, as well as their inherent complications.

CONCLUSION

The radiographic evaluation of the support and monitoring devices used in patients in the ICU is important, because the potentially serious complications arising from their introduction and use are often not clinically apparent. Familiarity with normal and abnormal radiographic findings is critical for the detection of these complications.

Oxygen reservoir bags simulating chest pathology: a case series

BACKGROUND

We present a series of plain chest radiographs taken in acute settings, with artifactual projections from oxygen reservoir bags. These artifacts are shown to simulate chest pathology in each case.

OBJECTIVES

The identification of artifacts on imaging prevents misdiagnosis and potential mistreatment of patients in acute settings. We highlight patterns of findings caused by the projection of oxygen reservoir bags in radiographs taken in the emergency setting.

CASE REPORTS

We present plain chest films in 4 patients taken in the acute setting, either in the emergency department or acute admissions unit. In this case series, oxygen reservoir bags simulate pneumothoraces, lung edges, and bullous disease.

CONCLUSION

Artifacts on chest radiographs are potential causes of misdiagnosis and subsequent inappropriate treatment. By highlighting the patterns created by the projection of oxygen reservoir bags, emergency physicians, radiologists, and reporting radiographers will be aware of the potential problems.

Thoracic and abdominal devices radiologists should recognize: pictorial review

OBJECTIVE

Surgical, interventional, and diagnostic devices are continually being developed and often have unexpected radiographic appearances. The purpose of this article is to familiarize the radiologist with several devices that may be placed in the thorax and abdomen.

CONCLUSION

The radiologist's familiarity with the radiographic appearance of devices placed in the chest and abdomen is essential for accurate image interpretation and identification of postprocedure complications.

Novel treatment options for chronic heart failure: a radiologist's perspective

OBJECTIVE

This article aims to familiarize radiologists with novel treatment options for chronic heart failure that is unresponsive to medical therapy, such as mechanical cardiac assist devices, surgical procedures, resynchronization therapy with biventricular pacing, and cellular cardiomyoplasty, and their radiographic appearances.

CONCLUSION

Heart transplantation as a treatment of debilitating heart failure provides an opportunity for meaningful long-term survival but is limited by a shortage of donor hearts. This has spurred the development of new treatment options for chronic heart failure that is unresponsive to medical therapy.

Imaging of implants on chest radiographs: a radiological perspective

Endovascular and percutaneous techniques have emerged as alternatives to surgical management in the treatment for a wide range of congenital and acquired cardiac, non-vascular and vascular conditions. Consequently, there has been an increasing use of implants such as closure devices, vascular stents (coronary, aortic, pulmonary and superior vena cava) and non-vascular stents like oesophageal and tracheo-bronchial stents. A large number of percutaneously sited implants are used for treating congenital cardiac anomalies such as atrial septal defects (ASD), ventricular septal defects (VSD), and patent ductus arteriosus (PDA). These implants take many shapes and forms. The aim of this review is to demonstrate the radiographic appearances of the various types of cardiovascular, bronchial and oesophageal implants that are visible on plain films. A brief outline of the aims and indications of various implant procedures, the general appearance of the commonest types of implants, and the radiological procedures are discussed. All radiologists are likely to come across implanted devices in plain film reporting. Imaging can be useful in identifying the device, assessing the position, integrity, and for the identification of complications related directly to the implant.

Misplaced devices in the chest, abdomen, and pelvis: Part II

Numerous medical devices are used in the chest and fewer in the abdomen and pelvis. They are frequently seen on various radiological studies in daily practice. Knowing the specific name of the device is not important. However, knowing the proper positioning and function of the device is necessary. It is a duty of the reporting radiologist to recognize the malpositioning or breakage of a medical device and to inform the responsible physician promptly, since these complications can have undesirable consequences and sometimes a fatal outcome.

Misplaced Devices in the Chest, Abdomen, and Pelvis: Part I

Numerous medical devices are used in the chest and fewer in the abdomen and pelvis. They are frequently seen on various radiological studies in daily practice. Knowing the specific name of the device is not important. However, knowing the proper positioning and function of the device is necessary. It is a duty of the reporting radiologist to recognize the malpositioning or breakage of a medical device and to inform the responsible physician promptly, since these complications can have undesirable consequences and sometimes a fatal outcome.

Part 2: Devices of the Head, Neck, Spine, Chest, and Abdomen

This gallery of medical devices illustrates a multitude of common devices in the head, neck, spine, chest, and abdomen that are found in daily radiologic practice (orthopedic devices for the extremities and pelvis were illustrated in Part 1). All these medical devices have been more thoroughly discussed in the previous articles in this medical devices series and in other detailed references. The present article is a comprehensive overview of these devices and provides a quick reference for identifying an unfamiliar device. It is intended to allow the reader to identify a device generically and to understand its purpose. It is important to recognize the presence of a device, understand its purpose and proper function, and recognize the complications associated with its use. Knowing the specific or proper brand name of every device is not important and frequently not possible. New devices are constantly being introduced, although most of them are variations of a previous device. Sometimes, so many devices are used in a patient's treatment that they obscure important anatomy and pathologic conditions (Fig 1). Herein, we present an overview of the many medical devices frequently used in the head, neck, and spine, including a halo device, aneurysm clips, spinal fusion devices, deep brain electrodes, sacral nerve stimulator, and vertebroplasty (Figs 2-9). We also illustrate numerous chest medical devices that are seen daily by almost all radiologists. These devices include a multitude of extrathoracic and intrathoracic apparatus, ranging from intravenous catheters to oxygen tubing and electrocardiographic leads, central venous catheters, chest tubes, endotracheal and feeding tubes, cardiac valves, coronary artery bypass stents, pacemakers, internal cardiac defibrillators, ventricular assist devices, and total artificial hearts (the latter two devices are frequently encountered in many large medical centers) (Figs 10-26). We also present medical devices of the abdomen and pelvis, which can be grouped into four major categories: intestinal tubes, genitourinary apparatus, postoperative apparatus, and vascular devices (Figs 27-47). For a detailed discussion of a particular device, the reader should refer to the appropriate references cited.