Video-based education improves the image quality of diagnostic percutaneous cerebral angiography among elderly patients

2.1 Study population

This study was conducted in Neurointerventional Center of Yijishan Hospital, Wannan Medical College from March 1, 2018, to September 1, 2018. This center is a tertiary 3,000-bed hospital, serving the population of about 30,00,000 in the southern part of Anhui Province. Eighty patients were provided with video-based education, and 80 age-matched patients with general education were enrolled in this study. Patients should fulfill the following requirements: (1) older than 65 years; (2) receiving the examination for the first time, without knowledge of DSA details before enrollment; (3) speaking Mandarin Chinese or local dialect and (4) owning an educational background of high school at least. Patients were excluded if they had cognitive impairment, were unwilling to participate in the study or lack communication skills. Data were removed if a patient finally had to receive therapeutic interventions for stenosis and aneurysm changes in arteries according to the results of diagnostic DSA. A flow diagram of the inclusion process of the study is shown in Figure 1.

Figure 1

Participant flow chart of the study.

1. Ethical approval: The research related to human use has been complied with all the relevant national regulations, institutional policies and in accordance with the tenets of the Helsinki Declaration and has been approved by the Ethics Committee of Wannan Medical College.

2. Informed consent: Informed consent has been obtained from all individuals included in this study.

2.2 Education system

One day before examination, patients in the intervention and the age-matched control would receive a brief handbook introducing examination machines and procedural details of diagnostic and therapeutic DSA in the form of texts and pictures. Then, an experienced physician blind to the study explained the details and answer questions from the patients. The physician would also tell the subjects the possibility and the processes of further therapeutic interventions based on the angiographic results. Besides, patients in the intervention arm would receive a video-based education. This video vividly describes the purpose, the whole processes of DSA procedure and a brief introduction of therapeutic interventions, with a length of 3 min. Subsequently, the same physician was available for consultation. Finally, patients in both control and intervention groups were guided to the operation room to gain familiarity with the entire procedure and the medical environment for 10–15 min. Familiarization involved showing the parts of the machines and the operation room. In addition, patients were told about the importance of minimizing motion while the scan was conducted. Several images were shown highlighting the effects of motion on image quality.

2.3 Diagnostic DSA procedure

Diagnostic cerebral DSA was performed using a biplane flat detector angiography suit (Artis Zee Flat Detector Biplane Angiosuite, Siemens). The system supported Digital Imaging and Communications in Medicine Radiation Dose Structured Reports. Standard dose imaging was done using the protocol defined by the manufacturer with the detector dose of 3.6 µGy/frame. All procedures were performed with systemic anticoagulation using heparin with an initial 3,000 U bolus, followed by an intraoperational re-bolus of 1,000 U at each additional hour. Percutaneous access was gained through the femoral artery employing the Seldinger technique. 6 F short sheaths were inserted into the artery. A guiding catheter (5 F) was advanced into the common carotid artery through a long 0.035-inch support wire. The aortic arch was imaged in the left anterior-oblique and anteroposterior view with 35–40 mL of contrast medium at an infusion rate of 15 mL/s. Six to nine milliliters of contrast medium was used per acquisition, consisting of one anteroposterior, one lateral and two oblique views of both internal carotid artery (ICA)s and vertebral artery (VA)s at the injection rate of 4–6 mL/s. DSA shots were acquired at 4 frames per second to a late venous phase by using a 36-cm² field of view, pixel size 0.15 × 0.15. Magnification views were done if necessary to clarify suspected changes. The intracranial circulation was included in all acquisitions. Rotational angiography was used when needed. After the procedure, patients were transferred to the neurology ward with continuous ECH monitoring for the following 24 h. Noninvasive blood pressure measurements were done every 0.5 h for the initial 4 h and every 2 h for the following 20 h.

2.4 Image quality

Images of ICAs and VAs in each individual were obtained for the quality assessment of anteroposterior and lateral DSA images, respectively. These images were excluded from assessment if any flow-limiting vascular stenosis/stenosis or artery steal phenomenon from arteriovenous shunts obscured relative opacification of a vessel segment or distribution. All analyses were performed in consensus by two independent neuroradiologists, each of whom has more than 5 years of clinical experience in cerebral imaging, on a system workstation (Siemens), without knowledge of the study design. Each DSA image was defined with respect to arterial, capillary and venous phases, determined by a 5-point scale on DSA images [15] (Table 1 and Figure 2) and followed by an average value of the total cumulative score.

Figure 2

DSA image quality score with picture illustration.

2.5 Data collection

Data on patient demographics, procedural equipment and technical details were collected. Radiation and time parameters were collected after every DSA event from machine and recorders’ reports, including radiation time, kerma air product (KAP), number of images, number of DSA shots and each shot duration.

2.6 Statistical analysis

Data were computerized and analyzed with the use of SPSS 21.0 software package. Data were summarized using frequency tables for categorical variables. Mean ± standard deviation (SD) was calculated for continuous parameters. All P values were two sided, and P < 0.05 was set as statistical significance.

3.1 Baseline characteristics

A total of 160 patients participated in this study and were allocated into control (n = 80) and intervention groups (n = 80) (Table 2). Thirty-three patients were excluded finally, of whom 29 received therapeutic approaches based on angiographic results (14 in control and 15 in intervention), and four proved to have unsuccessful angiography. Finally, there were 65 in control group (aged 70.65 ± 4.72 years) and 60 in intervention group (68.57 ± 7.80 years). There were no significant differences between the two groups with respect to age, gender, disease history and arch type (P > 0.05).

3.2 Image quality analysis

As presented in Tables 3, three patients in intervention group and one patient in control group were excluded in the image quality analysis, failing to export data from the working station. A careful review of the rest records revealed that video education before angiography induced a higher overall score of image quality than control, with respect to all arteries and overall image scores (P < 0.05).

The kappa consistency test values of the scores between the two observers were as follows: left internal carotid artery, 64.4%; right internal carotid artery, 62.8%; left vertebral artery, 67.9%; right vertebral artery, 68.3%.

3.3 Operation analysis

We found comparable results in time parameters between the two groups: operation time, DSA shot time and fluoroscopy time (P > 0.05; Table 4). Also, there were no significant differences in KAP, DSA shot dose, fluoroscopy dose and cumulative dose (P > 0.05).