Data collection
Clinical data collection and intra-operative measurements were performed
by the same researcher(EC). Patient demographics, weight, height, body
mass index(BMI), and occupational status were recorded. Occupational
status was categorized as light workers and heavy workers. Patients that
worked in jobs requiring physical strength, such as construction,
farming, delivery, were categorized as heavy workers, whereas office
employees, housewives, and the unemployed were categorized as light
workers.
Surgery was performed by experienced surgeons (FTA, CYB or MSY). All
nephrectomies were performed via the transperitoneal approach. In order
to record surgical data the researcher in charge (EC) and an
observer(FI) were present during all surgical procedures. Perirenal fat
dissection time was recorded by a time observer (FI). The complexity of
perirenal fat dissection was classified by EC and divided into 3
categories; easy, moderate, and difficult. This classification was based
on the difficulty of dissection, capsular trauma during dissection,
bleeding, and unintentional injuries during removal of perirenal fat
from the kidney. In addition, maximum perirenal fat thickness(mm) and
maximum subcutaneous fat thickness(mm) were measured intra-operatively
by EC. The removed perirenal fat tissue was sent for histopathological
examination after measurement.