1. Introduction
Cataract, in addition to heart disease and arthritis, is one of the most common causes of disability in the elderly. Phacoemulsification (phaco) is one of the most common and modern methods for treatment of cataracts, which is increasingly performed in Iran. Phaco surgery and its training can be one of the priorities of the health system. In this method, by creating a 3-mm incision on the sclera, the eye lens is removed after emulsification and replaced with a foldable lens and the patient is discharged the same day. The emulsification is performed by a needle that transmits ultrasonic waves to the environment, and then the fine particles are propagated through a hole in the middle of the needle. Anxiety is one of the most common emotional responses before and after surgery. The degree of anxiety in each patient depends on many factors. Anxiety is one of the possible factors in canceling unnecessary surgeries. Current therapies for modulating physiological responses caused by anxiety are mainly focused on drug interventions, such that sedatives and anti-anxiety drugs are prescribed before surgery. However, most medications have side effects. Videos can be used to educate patients in a shorter time, and since predefined content are used in them, they can be useful more than instant education. This study aims to evaluate the effect of educational videos on preoperative anxiety in patients undergoing eye surgery by phaco method.

2. Materials and Methods
The present study was a clinical trial using control and intervention groups. A total of 160 patients who were candidates for phaco surgery and had files in the Abu Reihan Clinic affiliated to the Social Security Organization of Tehran in 2018-2019 participated in this study who were selected by simple random sampling method and based on the inclusion criteria. After obtaining permissions, subjects completed a demographic form and Spielberger’s State-Trait Anxiety Inventory (STAI) the day before surgery. Then, the intervention group was given a short (10-min) educational video about phaco surgery, while for the control group, verbal explanations about phaco surgery were given. The content of the educational video were about the cataract disease, how phaco surgery is performed and how the patient is anesthetized, pre- and post-operative care, and reassuring the patient about the low complication of the surgery. The STAI was completed again 1 hour before going to the operating room. Data analysis was performed in SPSS v. 23 software by using descriptive and inferential statictics. Significance level was set at 0.05.

3. Results
The mean age of patients in the intervention and control groups was 58.63±7.68 and 62.32±9.15 years, respectively. There was no statistically significant difference in demographic characterictics between the two groups (Table 1).




There was a statistically significant difference in the scores of overt and covert anxiety after the intervention between the two groups (P=0.0001) (Table 2).



4. Conclusion
Training through short training videos has significant advantages that can lead to improved care, and if care providers are seeking comprehensive care, it is best to use this method for patients before surgery. Therefore, it is suggested that nursing managers provide conditions for short-term educational videos to be used as a low-cost and easy method for patients who are candidates for eye surgery. It is essential to train nursing staff to educate patients through educational videos and provide facilities for nurses to interact with patients.

Ethical Considerations
Compliance with ethical guidelines
This study was approved by the Ethics Committee of the Islamic Azad University, Tehran Medical Branch (Code: IR.IAU.TMU.REC.1398.147 & IRCT:20200115046145N1). All ethical principles are considered in this article. The participants were informed about the purpose of the research and its implementation stages. They were also assured about the confidentiality of their information and were free to leave the study whenever they wished, and if desired, the research results would be available to them.


Funding
The paper was extracted from the MSc.thesis of the first author at the Department of Nursing, School of Nursing and Midwifery, Tehran Medical Sciences Branch, Islamic Azad University, Tehran (Code: 13610403972004).

Authors' contributions
Conceptualization: Farhad Adhami, Mohammad Sahebzamani; Methodology, data collection: Dorna Sattar, Mehran Naghibeiranvand; Data analysis: Farhad Adhami, Mehran Naghibeianvand; Investigation, writing – original draft, and writing – review & editing: All authors.

Conflicts of interest
The authors declared no conflict of interest.

Acknowledgements
All author want to thank all Staff of Abu Reihan Clinic in Tehran.