Arunkumar Neelakandan^1*, Alex Daniel Prabhu Arul Pitchai², Einstein Arulraj³

^1,2,3Department of Radiology, Chettinad Hospital & Research Institute, Kelambakkam, Chennai, Tamil Nadu, INDIA.

Email: dr.arun.n@gmail.com

 RESULTS

In this study, the subjects' mean (±SD) age was 38 years, most 23 of whom belonged to the 30–39 years age group. Out of 100 subjects, 57 subjects were married, 31 were single, and 12 were widowed/divorced. A total of 47 subjects were educated up to graduation level, and only nine subjects were from the uneducated category. Twelve participants reported a positive family history of gonadal dysfunction/infertility (Table 1).

Table 1: General Demographic features of adult healthy subjects enrolled in this study.

The variations in the testicular volume of both the right and left testis in subjects were normally distributed, as highlighted in Table 2. Mean right and left testicular volumes were 21.97 ± 5.89 cm³ and 23.58 ± 5.62 cm³, respectively. The left testis's mean length, width, and height were 3.55 ± 0.28 cm, 2.49 ± 0.33 cm, and 2.61 ± 0.30 cm, and The right testis's mean length, width, and height were 3.53 ± 0.30 cm, 2.46 ± 0.34 cm, and 2.57 ± 0.30 cm, respectively. Although the left testis's length, width, and volume were larger than the right, these differences were statistically significant (p> 0.05).

Table 2: Average of measurement of general parameters of testes among all study subjects.

Data represents Mean ± SD values.

A comparison of testicular volumes by age, groups on both sides, is shown in Table 2. Across the age groups, the right testicular volumes were predominantly larger than the left side. However, in all the age groups, the results of a paired-samples t-test, as highlighted in the table, showed no significant differences on both right and left sides (p> 0.05).

Table 3: Relationship between subjects age, height, weight and body mass index (BMI)

Data represents Mean ± SD values.

The results analysis of variance to detect any significant differences or trends in testicular volume compared with BMI and age groups of subjects are presented in Table 3. The age group of 18-29 years had a maximum number of underweight subjects, and the age group of 40-49 years and 50-59 years had the maximum number of obese subjects.

Table 4: Assessment of correlation between subjects’ body mass index (BMI) categories and testicular volumes.

The results of correlation analysis to evaluate; further, the relationship between BMI and testicular volume measurements are presented in Table 4. Although there appears to be a gradual increase in left testicular volume from 21.47 ± 4.12 cm³ in the underweight category to 23.95 ± 2.98 cm³ in the obese, this trend was not statistically significant (p> 0.05). Similarly, the right testicular volume increased from 21.07 ± 3.21 cm³ to 23.16 ± 3.34 cm³, it was also not statistically significant (p> 0.05). There is generally a positive but weak correlation between BMI and testicular length, width, height, and volume on both sides. These showed that as the BMI increased, testicular dimensions increased.

Table 5: Analysis of various semen parameters from the participant’s group.

The conventional sperm parameters of the participants enrolled in this study were shown in Table 5. These patients with low testicular volume had a statistically significant lower seminal fluid volume, sperm concentration, and percentage of progressive motility and spermatozoa with normal form.

Table 6: Analysis of various serum hormone levels among the participant’s group.

The hormonal serum levels are displayed in Table 6. LH, FSH, and prolactin levels were similar among all the participants.

DISCUSSION

The measurement of testicular volume in adults is an essential parameter in evaluating the health status of the testes in various clinical conditions such as undescended testis, torsion, malignancies, orchitis and varicocele. In addition, the estimation of testicular volume is an integral aspect of male infertility evaluation.^1-3 Compared to Prader orchidometry or the punched-out orchidometer, ultrasound has generally been recognized to be the most accurate10, 12, 39 and testicular volume measurements using the ultrasonographic formula L x W x D x 0.71, which was employed in this study, has been reported to be the closest to actual testicular volumes in humans.^1-5 Moreover, the non-invasiveness of ultrasound and the absence of concerns about radiation allow for repeated evaluations. The sample selection criteria used in this study are similar to those used in earlier studies.^6-9 In these studies and the current one, participants with a history of testicular and scrotal surgery or disease were excluded from the study. The mean right and left testicular volumes obtained in this study were 21.97 ± 5.89 cm³ and 23.58 ± 5.62 cm³, respectively. This study also revealed an increasing trend in volumes as age advances to a peak in the late 30s, followed by a decrease in the volumes. This observed peak testicular volume at this period of life is consistent with 57 reports that have suggested that men are at their peak fertility at this period and that beyond 50 years of age, serum testosterone and spermatogenesis reduce with time.¹⁰ More detailed analysis showed no statistically significant differences in these trends for both right and left testes. Age was also positively but weakly correlated to the right length, left length and left testicular width. A negative and weak correlation was obtained between age and left testicular volume. This is different from the results obtained in other studies,^7-10 where age showed no correlation with the volume of the left and the right side of the testis. Few earlier studies had established that the testes achieved their maximal size by 18 years and remained so until 80 years when they started decreasing in size.^8-12 Further, the correlation analysis revealed a positive but weak correlation between BMI and testicular length, width, height and volume,^13-15 establishing a weak and positive correlation between testicular volume and body mass index. However, few studies.^9-13 showed a consistent lack of correlation between BMI and left testicular volume. Furthermore, as argued by Sotos and Tokar,⁷ the measurement of the testicular volume is not an exact science. Even with the reliability of the ultrasound, variability related to the transducer used, the possibility of compression of the testis, and intra- and inter-observer variation in the measurements (width, height, length, and volumes), among other factors, exists. In addition, other reasons such as environmental, nutritional and genetic factors may be responsible for these differences.^14-16 In general, in this study, it was found that the testicular volume had a positive but weak correlation with weight, height, BMI, but none was statistically significant. Although the left testis's length, width, and volume were larger than the right, these differences were statistically significant. However, no immediate scientific explanation could be inferred to the differential association of the right and left testes with the measured anthropometric parameters. This variation warrants further studies in this subject area to establish a clinical and scientific basis of the variations in right and left side testicular volumes. The results of this study indicate that participants with a reduced testicular volume, in the absence of testicular disease, show poorer semen parameters. The participants enrolled in this study did not show any frank endocrine alteration, but total testosterone serum concentration was lower in men with reduced testicular volume.

CONCLUSION

In this study, the right testicular volume showed less volume compared to the left testicular volume. Both side measurements have shown a positive but weak correlation with weight, height, BMI, but none was statistically significant in healthy adults. Further studies are needed to support or negate these findings. This anthropological study addressed an oft-repeated question about the accuracy of the different non-invasive methods of testicular measurements. A rough estimate of testicular size may suffice in cases that do not need any active intervention. Further studies are needed to clarify the relationship between reduced testicular volume and ultrastructural alterations of the testicular parenchyma in patients with low testicular volume and without evidence of disease at the clinical and ultrasound examinations. This study complies with the published data so far and revealed ultrasonography to be the most accurate and objective in vitro method of assessing testicular volume.

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