Hsiao et al developed 2 nomograms for evaluating successful reversal of a vasectomy using microsurgery. One nomogram is preoperative and one is postoperative. The authors are from Weill Cornell Medical College, Memorial Sloan-Kettering Cancer Center and the Cleveland Clinic.
Patient selection: male who has undergone microsurgical reversal of a vasectomy
Parameters:
(1) age in years, from 25 to 70 years of age
(2) duration of obstruction in years, from 0 to 30
(3) history of previous vasectomy reversal
(4) presence of sperm granuloma
(5) average testis volume in mL from 8.5 to 30 (or greater)
(6) type of reversal procedure performed
(7) sperm seen on intra-operative microscopy
(8) type of fluid seen at surgery
|
Parameter
|
Finding
|
Points
|
|
history of previous vasectomy reversal
|
no
|
22.5
|
|
|
yes
|
0
|
|
sperm granulomas
|
absent
|
0
|
|
|
present
|
3.3
|
|
type of reversal
|
bilateral vasoepididymostomy
|
0
|
|
|
unilateral vasovasostomy and unilateral vasoepididymostomy
|
7
|
|
|
bilateral vasovasostomy
|
18
|
|
sperm seen in intra-operative microscopy
|
no
|
0
|
|
|
yes
|
85
|
|
type of fluid
|
none or scant
|
13.8
|
|
|
thick, like toothpaste
|
0
|
|
|
clear, thin, copiois
|
39
|
|
|
cloudy, thin, copious
|
53
|
points for age =
= (0.0167 * ((years)^2)) - (3.032 * (years)) + 133.8
points for duration of obstruction =
= (0.01905 * ((years)^2)) - (3.586 * (years)) + 91.17
points for average testis volume from 8.5 to 22 mL =
= (-0.1016 * ((volume)^2)) + (10.75 * (volume)) - 85.19
points for average testis volume from 22 to 30 mL =
= (-0.9783 * ((volume)^2)) + (42 * (volume)) - 349.6
total score =
= SUM(points for all 8 parameters)
Interpretation:
• minimum score: 0
• maximum score: around 444
• The higher the score the greater the likelihood of patency.
|
Score
|
Percent with Patency
|
|
0 to 44
|
< 10%
|
|
45 to 243
|
(0.000617 * ((points)^2)) + (0.07809 * (points)) + 5.021
|
|
243 to 511
|
(-0.000571 * ((points)^2)) + (0.5711 * (points)) - 44.91
|
