AI vs Human: How to read an X-ray like a pro
Becoming a radiologist isn’t easy. It takes a lot of dedication and hard work. This is a fascinating specialty, with an incredibly diverse day-to-day workload. If someone likes puzzles, practical procedures, and being exposed to a broad range of pathologies, it may be the right career choice for them.
With the advancement in technology, radiology has seen tremendous growth in the past decade. From better scanning equipment to advanced tools, this development is warmly welcomed by the medical, scientific, and research community as modern medicine has also become increasingly reliant on imaging technologies to provide efficient and effective representation of diseases and illnesses.
In today’s blog post we will learn what are the steps that a radiologist follows when he does a chest radiography for a patient who may be coming for pulmonary problems.
The chest X-ray seems to be the most common diagnostic visualization technique used to assess respiratory issues. Its popularity comes from a number of variables, including the fact that it is inexpensive, quick, and simple to conduct, produces almost no irradiation, and is both accessible and feasible to patients and doctors.
Throughout the last century, the basic procedure of obtaining an X-ray has stayed mostly unchanged. Only in the last years we learned how to obtain better results thanks to ongoing improvements in image receptor technology and software utilization.
How to scan correctly
The radiologist’s preferred approach is the posterior-anterior perspective. These scans are obtained with the patient standing upright and towards the sensor. The X-ray tube is placed behind the person, with him being situated so that the extremities of both collarbones are equal visible from the thoracic vertebras in the middle. To allow an accurate image of the lungs, the shoulder blades are retracted and rotated externally.
The anterior-posterior perspective, on the other hand, is done with the patient’s backside to the sensor and the x-ray source in the front. Because this type of patients cannot always be positioned in an upright position, this view is most typically used on severely ill or weak patients. Both views have upsides and downsides, but the anterior-posterior projection’s main negative is the amplification of the heart outline.
The lateral projection is another perspective that is utilized. This is a good way to rule out apparent anomalies on a frontal X-ray and observe structures that are found behind the heart.
Chest X-rays were traditionally acquired with conventional film–screen radiography systems. However, picture resolution was a tradeoff and the film–screen combination’s narrowed exposure range. The doctor had to find the correct combination between sufficient exposure of the most transparent zone and the densest region. To maximize the picture quality, techniques including high and low kilovoltage exposures and rare earth phosphor screens were utilized.
The digital world
Film–screen radiography has been substantially overtaken by digital imaging systems due to exponential advances in processing power, allowing picture editing, digital storage capacity, and additional software technology to enhance the result. The difficulty of bone elements obscuring pathologies on traditional frontal Chest X-rays prompted the creation of electronic tomosynthesis and subtraction radiography. If you want to see how XVision’s algorithm works on this principle you can test it by clicking HERE.
The interpretation of an X-ray is a hard task made more difficult by the possibility of overlaying structures masking subtle discoveries, notably in the mediastinum. Nevertheless, understanding this process and becoming aware of places where anomalies are missed can reduce the chance of missing a substantial defect. The order in which a radiography is analyzed for lesions is mostly a matter of personal taste and what matters is the strict consistency that is applied to each examination to guarantee a careful inspection.
The X-ray’s projection, in addition to aiding diagnosis, gives an estimate of a patient’s medical status at the time of the capture. The PA projection can be confirmed while viewing the image, as the shoulder blades are offset from the lungs, overlapping the lateral ribs and chest wall soft tissues. A scan performed this way also indicates that the patient was well enough to attend the radiology department, stand, and have the image acquired as opposed to AP radiographs, which are generally performed when a patient is too unwell to perform the necessary maneuvers.
From top to bottom
Discovering all the iatrogenic elements (objects inserted by a medical specialist) in the picture is a good place to start. This consists of identifying all of the wires and tubes visible (such as nasogastric and endotracheal tubes, central venous lines, and pleural drains) and ensuring that they are projected over the correct anatomical structures.
The anatomical components of the thorax should be examined afterwards. The clinicians should check the subdiaphragmatic area for intraperitoneal air. It’s also a good idea to view the pleural areas for evidence of pneumothorax and pleurisy at this point. The soft tissues of the lateral rib cage needs to be examined for unusual formations and structural asymmetries. The supraclavicular spaces are examined at the end of the soft tissue inspection.
Next, the doctor needs to ensure that the trachea is located in the middle of the mediastinum, before moving on to the hila, which is made up of bronchi, arteries, veins, and lymph nodes. The left hilum is somewhat higher than the right hilum in healthy people, generally by a maximum of 2 cm due to the heart facing this way.
The structures should have a smooth contour and a constant diameter. An irregular hilum border, for instance, might signal lymph node hypertrophy. The radiologist should analyze the cardio-mediastinal structures after examining this area. For terms consisting in size, form, and location, it is more convenient to begin with the heart.
As a side note, XVision’s software uses an algorithm that calculates automatically the size of the heart in the form of a cardio-thoracic index.
Watch out for abnormalities
There are approximately 42 bones on an adequately taken chest X-ray and each one requires a thorough evaluation. The ribs on each side of the chest should be assessed in three stages: the posterior ribs, the anterior ribs, and the lateral rib angles, as subtle lesions here can easily be missed. Next, an inspection for deformities or fractures of the vertebrae, the clavicles, and the shoulder blades is needed.
Lastly, the lungs can be evaluated independently. The goal of comparing the right and the left side of the thorax is to find anatomical defects and asymmetries. To make this comparison easier, the doctors should split the lungs into three zones: upper, middle, and lower.
After this full assessment, a good radiologist always go back over the initial diagnostic questions that triggered the investigation to make sure it was resolved.
Although the procedure described above may seem time-consuming at first, with practice, a comprehensive examination may be completed with rapidity and clarity, and the danger of missing pathology is reduced.
Use a little help
XVision was designed to help radiologists be more, to be better. Our suite of products dedicated to the health of the lungs is seamlessly integrated into the doctor’s and hospital’s workflow, helping them to analyze the chest x-rays and lung CTs faster and more efficiently.
XVision is an extra brain that allows you to heighten your ability to analyze. You can see how it works here: https://scan.xvision.app/login
You can also read about how Artificial Intelligence improves Healthcare here.