# Does the contralateral testicular volume decide the need for diagnostic laparoscopy in cases of unilateral impalpable undescended testis?

## TL;DR

This study shows that measuring the volume of a normal testis can help predict the condition of an undescended testis, aiding in surgical decisions.

## Contribution

The study introduces a new method using testicular volume measurements to guide laparoscopic exploration in undescended testis cases.

## Key findings

- A larger contralateral testis volume correlates with specific intra-abdominal testis findings.
- The sonographic volume can predict the status of the undescended testis with 75% sensitivity and 88.89% specificity.

## Abstract

This study aimed the evaluation of the value of the calculated volume of a normal testis to predict the status of its contralateral impalpable side and hence decide the importance of laparoscopic exploration.

Patients with unilateral impalpable undescended testis – as confirmed by clinical and sonographic examination- were enrolled in our prospective interventional study between November 2018 and August 2022 at Elshatby University Hospital, Faculty of Medicine, Alexandria University. The volume and three-dimensional diameter of the normal contralateral testis were measured by the pre-operative US using the formula: Volume = L x W x H x π/6, where L is the length, W is the width, H is the height, and was correlated with the intra-operative laparoscopic findings.

Seventy-six patients were included in our study. The age of the studied patients ranged between 6 months and 4 years with a mean of 2.17 ± 1.30 years; most of them were between one and three years old. Forty-six patients (60.5%) have left-sided impalpable testis and 30 patients (39.5%) have right-sided impalpable testis. The calculated volume of the contralateral normal testis was significantly larger in those patients who had both blind ending vas and vessels (0.89 ± 0.16) and in those who had an atrophic testis passing through the deep inguinal ring (DIR) –which was excised through the inguinal region- (0.83 ± 0.20) than in those patients who had their testes intra-abdominal (0.53 ± 0.18) or passing through the DIR to the inguinal region (0.80 ± 0.19). (Kruskal Wallis test; p < 0.001*).

The calculated sonographic volume of a normal testis can predict the status of its contralateral impalpable side significantly with sensitivity & specificity of 75.0% & 88.89% respectively and a cut-off point of ≤ 0.674; hence, helps in parent counselling preoperatively.

Name of the registry: Clinicaltrials.gov PRS. Trial registration number: NCT05933811. Date of registration: 10-7-2023 (retrospectively registered). URL of trial registry record: https://clinicaltrials.gov.