Why can’t imaging examination reports be obtained immediately?

Author: Cong Xinying China Rehabilitation Research Center

Reviewer: Chen Zhenbo, deputy chief physician of China Rehabilitation Research Center

Figure 1 Copyright image, no permission to reprint

"Why can we get the film in just over ten minutes after the imaging examination, but have to wait for 2 hours or even longer for the report?" "Aren't the reports written by machines? Why is it so slow?" Such questions are often heard in clinical work. In fact, it is not that simple to issue a formal imaging report. Today, we will use easy-to-understand language to talk about how imaging reports are written and why they cannot be "available immediately" like films.

1. Patient completes initial examination

Generally speaking, from the patient to the imaging department for examination to receiving the report, there are 8 steps: ① Examination application form; ② Registration; ③ Examination; ④ Image post-processing; ⑤ Image transmission; ⑥ Initial report writing; ⑦ Report review; ⑧ Report issuance. It can be seen that the patient completing the examination is only the first 3 steps of the examination process, and there is still a lot of work to be done later.

2. Post-processing and reconstruction of original images

After the inspection, the technician first transfers the scanned original image to the workstation; then, the workstation performs various post-processing and reconstruction on the original image.

For example, chest CT images are reconstructed in the coronary and sagittal planes (equivalent to the anteroposterior and lateral planes); angiography examinations require more complex post-processing. Taking coronary artery CT angiography as an example, volume rendering, maximum density projection, surface reconstruction and other operations are required. This process takes a long time to complete. In the case of coronary artery bypass grafting, variations or more complex lesions, post-processing will take even longer.

3. The images are transmitted to the film viewing system, and the radiologists will "find faults"

After the post-processing is completed, the technician will upload the original image and the reconstructed image to a professional film viewing system (Medical Image Archiving and Communication System, which is the PACS system that everyone usually hears about from doctors). Generally speaking, it is a software that can view images and write reports on the hospital's internal network. Subsequent image reading and report writing will be completed on the PACS system. In addition, the transmission of image data also takes time. The transmission of examination images is similar to sending photos or short videos to each other on WeChat. If the photo has high pixels or the short video is long, you need to download it for a while before you can watch it. The difference is that the image is transmitted from the scanning machine or post-processing workstation to the PACS system. Since the image has high pixels and each frame is large, the transmission time will be longer. In addition, there are a large number of patients in the hospital who are undergoing various imaging examinations, and the number of films is huge, so the transmission time will increase accordingly.

After all the examination images arrive at the PACS system, the imaging physician can remotely view the patient's examination images. After opening the images, the doctor must first carefully check all the patient's information, including name, age, gender, clinical diagnosis, examination site and examination method, and then look at each image carefully.

At this point, you may say, it's just a few films, and you can finish reading them quickly, after all, the patient only gets three or five films. In fact, this is not the case. Although you get three or five films, in order to observe the lesions more carefully, the radiologist needs to read hundreds or even thousands of small images on the films. This is because the computer of the examination equipment will automatically thin the original image. For example, the chest CT image, the original image layer thickness is 5mm, and the thinned image layer thickness is 0.625mm, or even thinner. In this way, with the thinned images and post-processed images, the number of images is several times or even dozens of times the original image. Each image needs to be carefully observed and analyzed to find clues of the lesion, just like the "I come to find the difference" game. The game of finding the difference is to find the difference in a picture. Do you think it takes some time? And radiologists are doing this work conscientiously every day, and they are facing hundreds of images.

Figure 2 Which child is different from the others? (Copyrighted image, no permission to reprint)

4. Difficult cases require interpretation or discussion by multiple doctors

After the lesion is found, it is necessary to observe and describe the lesion in detail, including the location, number, size, shape, boundary, density or signal, enhancement mode and degree, relationship with surrounding tissue structure, and negative signs with differential diagnostic value. In case of difficult cases, it is also necessary to ask the patient or clinical doctor for a more detailed medical history, including the patient's symptoms, other examinations done, family history, etc.

At this time, you may say: "Isn't it just a picture? What's there to ask? Just write down what you see. Is it necessary to ask so many questions? Asking so many questions, does it mean that the doctor's diagnostic level is not good?" In fact, it is not the case. There is a saying in the imaging profession, called different diseases with the same image, the same disease with different images. Different diseases with the same image means that different diseases may present the same or similar imaging manifestations. For example, lung cancer, tuberculosis and pneumonia may look like a nodule or multiple nodules, but what exactly this lung nodule is needs to be combined with the patient's medical history, clinical symptoms and other examination results. The same disease with different images means that the same disease may show different imaging characteristics at different stages of development or due to individual differences. For example, tuberculosis, in the early stage, it looks like a white cloud on the film, and in the chronic stage, it looks like a cord and calcification, or one side of the lung may be deflated. For imaging diagnostic physicians, comprehensive consideration of the patient's medical history, clinical symptoms and other examination results can help them interpret the image more accurately, thereby providing patients and clinicians with more reliable diagnostic basis. In order to reduce the possibility of misdiagnosis, the above process of viewing images and writing reports requires another doctor with more experience to review all the images again and verify the accuracy of the reports. Only after verification and confirmation can the official report be issued to you.

For more complicated and difficult cases, it is necessary to consult materials, discuss with several doctors, or even consult with clinical doctors to find out what the disease is. These processes take time, which explains why you cannot get the report on time in rare cases. For patients who need to be reexamined, the imaging physician also needs to review the previous images and compare them one by one to observe whether the lesions have changed. For example, if there are multiple nodules in the lungs, each nodule needs to be carefully compared to see if there are any changes.

5. Report Writing

At present, the imaging department is facing a situation of heavy workload and few doctors writing reports. In the imaging department of the author's hospital, on average, each doctor has to complete about 80 CT/MRI reports every day, writing from morning to night, and overtime has become the norm. Even so, it is sometimes difficult to cope with the increasing workload. No matter how busy or tired, as long as the imaging doctor sits in front of the computer, he must practice the "patient-centered" service concept, write every report carefully, serve every patient with heart, and make every patient satisfied.

Now you should understand why the imaging report cannot be "obtained immediately". The imaging report is not written by a machine, but by a group of specially trained and experienced imaging diagnostic doctors after careful observation and careful thinking. Perhaps you have another question. Since the imaging report cannot be obtained immediately, will it delay the treatment of emergency and critically ill patients? This falls within the range of imaging "critical values". Imaging "critical values" are all imaging findings found by the imaging department that may endanger the patient's life and require the clinical department to provide effective diagnosis and treatment measures in a timely manner. When encountering this situation, the imaging diagnostic physician will immediately inform the attending doctor, nurse, or even the patient himself or his family of the examination results by phone so that the attending doctor and nurse can perform rescue or treatment as quickly as possible.

Meticulous craftsmanship makes a masterpiece, and repeated tempering makes true gold. The same goes for imaging reports. Therefore, please be more understanding, patients and their families, and give the diagnosing physician more time. This will also provide an extra guarantee for your health.