Hemoptysis is defined as bleeding arising from the lower airways. Identifying the etiology of hemoptysis and classifying it in terms of the amount of blood expectorated as well as the rate of bleeding play a fundamental role in defining the timing, way and place of managing a patient with hemoptysis. There are multiple causes of hemoptysis, including airway diseases, parenchymal lung diseases, cardiovascular diseases, and others. However, no cause is identified in 15–30% of all cases, and is termed idiopathic or cryptogenic hemoptysis. In the majority of cases, the source of massive hemoptysis is the bronchial circulation. However, nonbronchial systemic arteries can be also a significant source. Imaging modalities pertinent to the evaluation of hemoptysis include chest radiography, computed tomography, and bronchial arteriography. Conditions such as bronchiectasis, chronic bronchitis, lung malignancy, tuberculosis, and chronic fungal infection are easily detected with conventional CT. Even, CT is superior to fiberoptic bronchoscopy in finding a cause of hemoptysis, its main advantage being its ability to show distal airways beyond the reach of the bronchoscope, and the lung parenchyma surrounding these distal airways. However, more recently, the development of multidetector row CT has provided a comprehensive, noninvasive method of evaluating the entire thorax. At the same time, the combined use of thin-section axial scans and more complex reformatted images allows clear depiction of the origins and trajectories of abnormally dilated bronchial or non-bronchial systemic arteries that may be the source of hemorrhage requiring embolization.
Table of Contents
Introduction
Review of the literature
Chapter I: Anatomical Overview
The Pulmonary arteries
The pulmonary veins
Chapter II: Pathophysiology of hemoptysis
Clinical Significance
Causes of Hemoptysis
Physical Examination:
Pathophysiology:
Diagnostic modalities in hemoptysis:
Chapter III: Multi-detector row CT & hemoptysis
Multi–Detector Row CT Technique
Data Manipulation and Image Interpretation
Assessment of the Lung Parenchyma
Assessment of Pulmonary and Systemic Vasculature Arteries
Bronchial Arteries
Nonbronchial Systemic Arteries
Bronchial-to-Systemic Artery Communications
Cryptogenic Hemoptysis
Patients and Methods
Patients
Multidetector CT
Results
Case presentations
Case 1
Case 2
Case 3
Case 4
Case 5
Case 6
Case 7
Case 8
Case 9
Case 10
Discussion
Conclusions
Research Objectives and Thematic Focus
This study aims to evaluate the efficacy of multidetector row computed tomography (MDCT), specifically leveraging advanced applications like reformatted imaging and high-resolution post-processing, in managing patients presenting with hemoptysis. A core objective is to define the diagnostic utility of MDCT angiographic techniques in precisely locating bleeding sites and identifying their vascular origins, thereby facilitating optimized therapeutic interventions.
- Clinical evaluation and management strategies for patients with hemoptysis.
- Application of MDCT and advanced post-processing techniques in thoracic imaging.
- Identification of bronchial and nonbronchial systemic arteries as potential bleeding sources.
- Correlation between MDCT findings and interventional angiography results.
- Diagnostic accuracy of noninvasive imaging compared to traditional bronchoscopy.
Excerpt from the Book
Multi–Detector Row CT Technique
An extended spiral CT study of the thorax can easily be performed with a 16–detector row scanner during a single breath hold (normally lasting less than 15 seconds) in most patients. However, only a limited study with a four– detector row or single– detector row scanner may be possible, depending on the patient’s respiratory capacity. Image acquisition should be performed in a craniocaudal direction from the base of the neck to the level of the renal arteries to include the supraaortic great vessels and the infradiaphragmatic arteries, which may be responsible for an abnormal collateral contribution to the lungs (Murayama, et al., 2006).
With current multi– detector row systems, optimal enhancement of both the pulmonary and systemic arteries is achieved with the injection of approximately 120 mL of a relatively high-density contrast material (350 mg/dL) at a rate of 4 mL/ sec via an 18-gauge cannula into an antecubital vein or central venous catheter. The scan should be started during the phase of peak systemic arterial enhancement. (Table 2) Images should be acquired with thin collimation and with the table movement adjusted to allow extended volume coverage during a single breath hold. By adjusting. The exposure parameters and kilovoltage according to the patient’s weight, the radiation dose to the patient can be minimized without compromising image quality. (Kauczor, et al., 2004).
In certain cases, it may be useful or even necessary to perform follow-up CT several months after the episode of hemoptysis to study the evolution of underlying parenchymal lung abnormalities or to exclude the possibility that a small malignancy may have been missed at initial CT (Dweik, et al., 2009). Repeat evaluation of the bronchial arteries is not usually necessary unless there is continued hemoptysis; consequently, follow-up imaging can be performed without intravenously administered contrast material and at low milliamperage to minimize the radiation dose to the patient, which is of particular importance in young patients.
Summary of Chapters
Introduction: Provides the clinical definition of hemoptysis, outlines the various etiologies and imaging challenges, and establishes the study's aim regarding MDCT utility in Upper Egypt.
Review of the literature: Examines the vascular anatomy of the lungs, specifically the bronchial and pulmonary circulations, and reviews existing diagnostic modalities.
Chapter I: Anatomical Overview: Details the structure and function of the primary pulmonary circulation and the secondary bronchial circulation, highlighting the significance of their anastomoses.
Chapter II: Pathophysiology of hemoptysis: Explores the clinical definition, classification, and diverse pathologic mechanisms of hemoptysis, including infectious, vascular, and malignant causes.
Chapter III: Multi-detector row CT & hemoptysis: Discusses the technical protocol, image interpretation, and clinical application of MDCTA for the comprehensive assessment of vascular and parenchymal sources of bleeding.
Patients and Methods: Describes the prospective study design involving 52 patients, detailing patient selection, scanning protocols, and statistical analysis methods.
Results: Presents findings regarding demographic data, the diagnostic accuracy of MDCT, and the identified etiologies of hemoptysis in the studied cohort.
Case presentations: Illustrates the study findings through ten specific patient cases demonstrating varied clinical presentations and radiological features.
Discussion: Interprets the study results in the context of existing research, emphasizing the effectiveness of MDCTA and its limitations.
Conclusions: Reaffirms the value of MDCT as a primary, noninvasive, and comprehensive tool for mapping vascular sources of hemoptysis for future embolization planning.
Keywords
Hemoptysis, MDCT, Bronchial Artery, Pulmonary Circulation, Angiography, Embolization, Lung Cancer, Bronchiectasis, Vascular Anatomy, Thoracic Imaging, Non-invasive Diagnostics, Radiology, Interventional Procedures, Etiology, Clinical Management
Frequently Asked Questions
What is the primary focus of this research?
This work evaluates the utility of Multidetector Row CT (MDCT) as a comprehensive, noninvasive imaging modality for diagnosing and managing patients with hemoptysis, particularly in the context of identifying vascular sources for potential embolization.
What are the core thematic fields covered?
The research spans clinical pulmonology, diagnostic thoracic radiology, vascular anatomy, and interventional procedures, with a focus on bronchial and nonbronchial systemic artery identification.
What is the main objective of the study?
The primary aim is to report on the institution's experience using MDCT applications—such as high-resolution imaging and post-processing—and to determine the additional benefits of MDCT angiography in identifying the precise vascular source of bleeding.
Which scientific methods are employed?
The study utilizes a prospective clinical design, incorporating patient history, physical examinations, plain chest radiography, MDCT angiography, and, where clinically indicated, fiberoptic bronchoscopy and digital subtraction angiography (DSA).
What does the main part of the book address?
The main text covers anatomy, pathophysiology, specific MDCT techniques, and clinical case presentations, followed by a discussion on the accuracy of MDCT in identifying bleeding etiologies and vascular anomalies compared to standard diagnostic practices.
How would you characterize this work with keywords?
Key terms include Hemoptysis, MDCT, Bronchial Artery, Vascular Anatomy, Thoracic Imaging, Interventional Procedures, Etiology, and Clinical Management.
Why is MDCT superior to standard bronchoscopy in some aspects?
MDCT allows for the visualization of distal airways beyond the reach of a bronchoscope and provides a noninvasive map of the entire thoracic vasculature, including abnormal systemic arteries that might be missed by fiberoptic methods.
What role do bronchial arteries play in hemoptysis?
Bronchial arteries are the most common source of systemic blood supply contributing to hemoptysis; identifying their dilation and tortuous trajectory is critical for the success of interventional embolization.
What is the clinical significance of identifying nonbronchial systemic arteries?
Missing these arteries during the initial diagnostic phase or during bronchial artery embolization (BAE) is a common cause of early recurrent bleeding, making their identification essential for definitive treatment.
What limitation does the author mention regarding the study device?
The author notes that they used a 16-detector row scanner, whereas the literature suggests that 64-slice CT scanners provide superior resolution of bronchial artery anatomy.
- Arbeit zitieren
- Sherif Mohamed (Autor:in), 2015, Utility of MDCT in Hemoptysis. A Clinico-Radiological Study, München, GRIN Verlag, https://www.grin.com/document/444917
