The goal of this multicenter observational study is to develope and validate a new scoring system for preoperative prediction of difficulty of Laparoscopic Donor Nephrectomy. Healthy living kidney donors will be enrolled. The main questions it aims to answer are: 1) can the investigators predict difficulty of the operation ? 2) Can the investigators score difficulty based on this new scoring system? Difficulty of LDN will be graded by the operating surgeon at the end of the operation based on intraoperative predefined parameters. All operations will be blindly scored by the operating surgeon, while one radiologist will blindly review all preoperative CT scans. LAPDOCTOR scores will be compared with the degrees of difficulty assigned by the operating surgeon to investigate the match rate.

The LAPDOCTOR scoring programme calculates the score based on presence, absence of certain characteristics (Sex, BMI, different radiologic measurements, etc.). A score of 1 to 2 is assigned to each characteristics . Difficulty is graded as standard when the sum is between 11 and 18, moderately difficult between 19 and 25, very difficult between 26 and 33). At the end of the operation the donor surgeon will score the difficulty assigning a score of 1 to 3 to each phase of the operation, the resulting score will define again three degree of difficulty (standard 1-8, moderately difficult 9-16, very difficult 17-24.

Inclusion Criteria:

- Age of donor ≥ 18 yrs (minimum 18, maximum , deemed suitable for donation at the end of work-up

Exclusion Criteria:

• age< 18 yrs
• hypertension with organ damage
• unable to express proper consent to procedure
• evidence of coercion
• drug abuse
• evidence of malignancy
• pregnancy
• major respiratory or cardiovascular risk
• diabetes mellitus
• renal disease
• systemic disease with renal involvement
• thrombophilia
• BMI >35
• active infection
• hepatitis B, hepatitis C and HIV

Candidates to living kidney donation