These causes can range from vocal abuse and misuse to systemic diseases. Causes of dysphonia can be divided into five basic categories, although overlap may occur between categories. (Note that this list is not exhaustive):

Employment
It has been suggested that certain occupational groups may be at increased risk of developing dysphonia due to the excessive or intense vocal demands of their work. Research on this topic has primarily focused on teachers and singers, although some studies have examined other groups of heavy voice users (e.g. actors, cheerleaders, aerobic instructors, etc.). At present, it is known that teachers and singers are likely to report dysphonia. Moreover, physical education teachers, teachers in noisy environments, and those who habitually use a loud speaking voice are at increased risk. The term clergymans throat or dysphonia clericorum was previously used for painful dysphonia associated with public speaking, particularly among preachers. However, the exact prevalence rates for occupational voice users are unclear, as individual studies have varied widely in the methodologies used to obtain data (e.g. employing different operational definitions for "singer"). Mechanism
Located in the anterior portion of the neck is the larynx (also known as the voice box), a structure made up of several supporting cartilages and ligaments, which houses the vocal folds. In normal voice production, exhaled air moves out of the lungs and passes upward through the vocal tract. At the level of the larynx, the exhaled air causes the vocal folds to move toward the midline of the tract (a process called adduction).
To prevent infections, the incision is covered with a sterile bandage or surgical adhesive. Laparoscopic appendectomy
Laparoscopic appendectomy was introduced in 1983 and has become an increasingly prevalent intervention for acute appendicitis. This surgical procedure consists of making three to four incisions in the abdomen, each 0.25 to 0.5 inches (6.4 to 12.7 mm) long. This type of appendectomy is made by inserting a special surgical tool called a laparoscope into one of the incisions. The laparoscope is connected to a monitor outside the persons body, and it is designed to help the surgeon to inspect the infected area in the abdomen. The other two incisions are made for the specific removal of the appendix by using surgical instruments. Laparoscopic surgery requires general anesthesia, and it can last up to two hours. Laparoscopic appendectomy has several advantages over open appendectomy, including a shorter post-operative recovery, less post-operative pain, and lower superficial surgical site infection rate. However, the occurrence of an intra-abdominal abscess is almost three times more prevalent in laparoscopic appendectomy than open appendectomy. Laparoscopic-assisted transumbilical appendectomy
In pediatric patients, the high mobility of the cecum allows externalization of the appendix through the umbilicus, and the entire procedure can be performed with a single incision. Laparoscopic-assisted transumbilical appendectomy is a relatively recent technique but with long published series and very good surgical and aesthetic results. Pre-surgery
The treatment begins by keeping the person who will be having surgery from eating or drinking for a given period, usually overnight.