Measurement of testicular volume by ultrasonography

Hormone measurements and histomorphological observations in male Bactrian camels

The aim of this study was to investigate the effect of age on the hypothalamic-pituitary-gonadal (HPG) axis hormones and to determine the morphological changes of the testis. The Bactrian camels were divided into two groups based on their ages. The results showed that the testicular weight was significantly heavier in adult male camels than in pubertal male camels (P < 0.05). There were also significant differences between testicular length, testicular width, and testicular volume (P < 0.05). In the testes of both pubertal and adult male camels, Sertoli cells, spermatogonia, spermatocytes, round spermatids, and elongated spermatids were observed. Adult male camels had more Sertoli cells (P < 0.01) and elongated spermatids (P < 0.05). The concentrations of testosterone, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) were higher in the plasma and testes of adult camels than in pubertal camels (P < 0.05). E2 concentrations were lower in adult camels than in pubertal camels (P < 0.05). The testosterone levels in testicular tissue were higher than in blood plasma in both adult and pubertal stage (P < 0.05). In conclusion, these findings provide supportive knowledge and show the significant differences in terms of testicular volume, testicular hormone concentrations, and testicular morphology between different developmental stages in Bactrian camels.

Insights into the implication of obesity in hypogonadism among adolescent boys

OBJECTIVES

This research aimed at uncovering the mechanisms behind obesity-related hypogonadism in adolescent boys and to investigate the association between anthropometric characteristics and testicular functions of these boys.

METHODS

This study included 60 adolescent boys (12-18 years) with exogenous obesity (BMI≥95th percentile) and 30 age matched lean controls (BMI=15th-85th percentile). Full clinical examination, anthropometric measurements and pubertal assessment were performed. Laboratory investigations included hemoglobin, hematocrit, lipid panel, LH, FSH, free and total testosterone, inhibin B and estradiol.

RESULTS

The results indicated the presence of positive family history of obesity in 85% of obese boys vs. 40% of the lean counterparts. Concerning SBP of obese boys, 7% were hypertensive (95th percentile), 25% were prehypertensive (between 90th and 95th percentiles) while, DBP findings showed that 33% are hypertensive and 33% are prehypertensive. Meanwhile, 13.3% of lean controls were prehypertensive. Anthropometric measurements and lipid profile values revealed a significant difference between obese and lean boys. Compared to obese boys the normal weight boys had higher levels of free testosterone (21.15 ± 2.90 pg/mL vs. 11.38 ± 3.96 pg/mL, p<0.001), total testosterone (10.59 ± 6.63 ng/dL vs. 3.23 ± 1.70 ng/dL, p<0.001), FSH (7.33 ± 3.75 mIU/mL vs. 5.63 ± 3.96 mIU/mL, p=0.026) and inhibin B (83.28 ± 27.66 pg/mL vs. 62.90 ± 17.85 pg/mL, p=0.001) and they registered lower level of estradiol (18.48 ± 7.33 pg/mL vs. 40.20 ± 7.91 pg/mL, p<0.001). In obese boys, BMI SDS significantly correlated with lipid profile and estradiol whereas, it showed significant negative correlation with LH, free and total testosterone and inhibin B. Penile length significantly correlated with LH while it revealed significant negative correlation with cholesterol.

CONCLUSIONS

This study evidenced a close association between obesity and hypogonadism in adolescent boys which could be due to the increased estradiol level and decreased T/E2 ratio.

Contralateral testicular hypertrophy is associated with a higher incidence of absent testis in children with non-palpable testis

BACKGROUND AND OBJECTIVE

The objective of our study is to examine the impact of monorchism on contralateral testicular size in children with non-palpable testis (NPT). Enhanced contralateral testicular volume or longitudinal diameter (length) serves as a predictor of monorchism. In the present study, we assessed the ability of ultrasound measured enlarged contralateral testicular length for predicting monorchism (and hence a testicular nubbin) in children with NPT. Furthermore, we evaluated the general prevalence of viable versus non-viable testes in patients referred to our institution with unilateral undescended testis between 2005 and 2020.

STUDY DESIGN

We analysed the records of 54 patients who underwent diagnostic laparoscopy for NPT between 2005 and 2020 in a European tertiary care centre. Testicular lengths (longitudinal diameter) and testicular volume of the contralateral testis, as well as surgeon (surgeon 1 vs surgeon 2 vs others) and age at surgery (months) were assessed and stratified according to intraoperative findings (presence or absence of a testicular nubbin). Testicular length and volume were evaluated by ultrasound examination in office prior to surgery. Chi-square and t-test for descriptive analyses as well as uni- and multivariable logistic regression analyses were performed using R Version 3.1.0 (R Project for Statistical Computing, www.R-project.org).

RESULTS

A total of 15 children presented with viable testes and 39 patients with testicular nubbin. Mean age was 20.5 months in the overall cohort and 22.6 vs 19.7 months in children with viable testis vs testicular nubbin (p = 0.4). In patients with presence of a testicular nubbin, the contralateral testis was larger (median length 17 mm (16-19.2)) as compared to patients with a viable testis (median length 15 mm (14-17), p = 0.001). Similarly, contralateral testicular volume was lower in patients with a present viable testis (0.6 ccm vs 0.8 ccm; p < 0-001). This effect remained statistically significant when logistic regression analyses were adjusted for age and weight at surgery, year of surgery, surgeon, and laterality. OR (odds ratio) for presence of a testicular nubbin was 1.6 (per mm) [95% CI (confidence interval) 1.13-2.17; p = 0.007].

CONCLUSION

Patients with preoperative increased length and volume of the contralateral testis in the ultrasound examination are at significantly higher risk of monorchism than their counterparts with lower testicular length. This should be emphasized during counselling of the parents prior to surgery. In our experience parents cope more easily with the diagnosis of monorchism, once this has already been discussed and explained thoroughly prior to surgery.

Low BMI, but not high BMI, influences the timing of puberty in boys

BACKGROUND

Previous studies investigating the association between weight status and onset of puberty in boys have been equivocal. It is currently unclear to what extent weight class influences puberty onset and progression.

OBJECTIVES

To explore the relationship between degree of sexual maturation and anthropometric measures in Norwegian boys.

METHODS

The following endpoints were collected in a Norwegian cross-sectional study of 324 healthy boys aged 9-16: ultrasound-determined testicular volume (USTV), total serum testosterone, Tanner pubic hair stage, height, weight, waist circumference (WC), subscapular skinfolds (SSF), and body fat percentage (%BF). Testicular volume-for-age z-scores were used to classify "early," "average," or "late" maturing boys. Ordinal logistic regression analyses with a proportional odds model were applied to analyze the association between anthropometric variables and age-adjusted degree of pubertal development, with results expressed as age-adjusted odds ratios (AOR). Cumulative incidence curves for reaching pubertal milestones were stratified by BMI.

RESULTS

Boys with a low BMI for age (BMI_z  < -1) were less likely to have reached a pubertal testicular volume (USTV ≥ 2.7 mL) or a pubertal serum level of testosterone (≥0.5 nmol/L) compared to normal weight boys (AOR 0.3, p = 0.038, AOR 0.3, p = 0.026, respectively), and entered puberty on average with a delay of approximately eight months. Boys with high BMI for age (BMI_z  > 1) exhibited a comparable timing as normal weight boys. The same was found for WC. Pubertal markers were not associated with SSF or %BF.

CONCLUSION

By examining the association between puberty and weight status classified as low, average, or high, we found that a low BMI or WC for age were associated with a less advanced pubertal development and delayed timing of puberty in boys. No significant association was observed for a high BMI or WC. Moreover, no significant effects of SSF or %BF were observed. A low weight status should also be considered when assessing pubertal development in boys.

Testicular hypertrophy as predictor of contralateral nonpalpable testis among Chinese boys: An 18-year retrospective study

OBJECTIVE

To assess the accuracy of contralateral testis hypertrophy for predicting the fate of nonpalpable testis in Chinese boys at different ages.

METHODS

The data of patients who presented with unilateral impalpable testis and who underwent laparoscopy at the Children's Hospital of Chongqing Medical University between January 1, 2000 and January 1, 2018 were reviewed. The boys were divided into four groups: age-matched volunteers with no testicular abnormalities represented the control group (group I), boys with palpable undescended testis (group II), boys with nonpalpable testis (NPT)/viable testis (VT) (group III), and boys with NPT/non-viable testis (NVT) group (group IV). Scrotal testes were prospectively measured by ultrasonography for volume and size, and diagnostic laparoscopy was performed to determine the state of the cryptorchid testis.

RESULTS

The mean contralateral testicular volume and length in the boys with an absent testis was 0.78mL and 17mm compared with 0.67mL and 15mm in the boys with a testis present and 0.63mL and 15mm in the controls, respectively (P<0.05). The predictive accuracy, sensitivity, and specificity for an absent testis were 64.9%, 75%, and 49%, respectively, for volume and 64.2%, 56.3%, and 76.4%, respectively for length at the optimal cutoff value of 0.65mL volume and 16.55mm length. Contralateral testis volume was the most accurate in predicting monorchism in 0-2-year-olds (sensitivity: 75%, specificity: 70%, accuracy: 73.1%) and the contralateral testicular length was most accurate for 4-6-years-old (sensitivity: 68.6%; specificity: 77.8%; accuracy: 72.2%). We also included 29 patients with bilateral undescended testis (UDT) and with unilateral nonpalpable. Cutoff values for testicular volume and length were 0.6mL (sensitivity: 81.8%, specificity: 88.9%, accuracy: 86.2%) and 13.5mm (sensitivity: 63.6%, specificity: 77.8%, accuracy: 77.8%).

CONCLUSION

The present results exclusively obtained from laparoscopic exploration suggest that a testis volume of>0.65mL or a testis length of>16.55mm could predict monarchism with an accuracy of about 65%. In younger patients aged 0-2 years and 4-6 years, the overall predictive accuracy increases to about 73% but laparoscopic exploration is still required.

Semen parameters and testicular dimensions in small breed dogs below ten-kilogram bodyweight

Because of few available data on semen parameters in small breed dogs, the study aimed to analyse semen and measure testes of dogs ≤10.0 kg bodyweight. Semen was collected from 41 fertile stud dogs, which were divided based on bodyweight: group 1 ≤ 5.0 kg and group 2 between 5.1 and 10.0 kg. Median values for ejaculate volume (group 1: x ~ 1.2 ml; group 2: x ~ 2.2 ml), total sperm output (group 1: x ~ 110.7 × 10⁶ ; group 2: x ~ 215.1 × 10⁶ ) and testicular volume (group 1: left testicle x ~ 2.8 ml, right testicle x ~ 2.7 ml; group 2: left testicle x ~ 5.5 ml, right testicle x ~ 5.0 ml) were lower in group 1 compared to dogs of group 2 (p = .001; p = .001; both testes: p < .001). There was no difference in sperm concentration (p = .985). Based on these results, introduction of an additional weight group to the commonly used reference values is recommended, since values for ejaculate volume, total sperm output and testicular dimensions for dogs ≤5.0 kg bodyweight differed significantly from values of dogs with a bodyweight from 5.1 to 10.0 kg.

Ultrasound-based measurements of testicular volume in 6- to 16-year-old boys - intra- and interobserver agreement and comparison with Prader orchidometry

BACKGROUND

Prader orchidometry has been the standard method for evaluating testicular size. As this technique is subjective and tends to overestimate the testicular volume, ultrasound (US) has been proposed as more reliable.

OBJECTIVE

To evaluate the intra- and interobserver agreement of US measurements of testicular volume and to compare US with the Prader orchidometer.

MATERIALS AND METHODS

Dimensions of the right testicle were measured using US in 57 boys ages 6.5 to 16.4 years (mean: 12.0 years). The measurements were performed twice by one main observer and once by a second observer. A third observer estimated testicular volume using a Prader orchidometer. Agreement was investigated with Bland-Altman plots, summarized as the mean and standard deviation (SD) of differences, 95% limits of agreement and technical error of measurement.

RESULTS

Mean intra-observer difference of testicular volume was 2.2%, SD=9.2% (limits of agreement: -20.3 to 15.9%) and technical error of measurement 6.5%. The mean interobserver difference was 4.8%, SD=20.7% (limits of agreement: -35.7 to 45.3%) and technical error of measurement 14.6%. Comparing US and orchidometer volumes required conversion that was nonlinear and volume dependent, estimated as Vol_OM = 1.96×Vol_US^0.71. The mean difference after transformation was 0.7% with an SD of 18.0% (limits of agreement: -34.5 to 35.9%).

CONCLUSION

Our results showed a small mean intra- and interobserver difference that indicates the potential of US for measurement of testicular volume at group level. The intra-observer error was limited, which justifies its use in longitudinal follow-up of testicular development in an individual child, but the larger interobserver variability indicates the need for good standardization of methods. Agreement between the two methods requires a power transformation.

Comparison between testicular volumes as measured with prader orchidometer and ultrasonography in Healthy Nigerian Newborns

BACKGROUND

We compared the testicular volume (TV) measured with Prader orchidometer (PO) to the volume measured with ultrasonography in male neonates and their relationships with some selected neonatal characteristics.

SUBJECTS AND METHODS

A cross-sectional study of all term male neonates who had clinical examination of their external genitalia performed and TV was measured using PO and ultrasonography. Information about the gestational age, birth weight, and birth length was also recorded to determine their relationships with TV measured.

RESULTS

The mean TV measured with PO was 1.06 (standard deviation [SD] ± 0.24) ml for both sides. With ultrasonography, the mean left TV was 0.273 (SD ± 0.081) ml and the mean right TV was 0.272 (SD ± 0.079) ml. There were significant correlations between TV using both methods with the birth weight and length.

CONCLUSION

TV measured with the two methods was comparable and correlates well with their birth weight and birth length.

Appraisal of testicular volumes: volumes matching ultrasound values referenced to stages of genital development

Background

Testicular volumes obtained with orchidometers or external linear measurements in the scrotum (centimeter ruler or calipers) grossly over-estimate ultrasound volumes, have much variability and may not be accurate or reproducible. The reference of the values obtained by orchidometers or US, to age or Tanner stages is not useful to determine the normal values for stages of puberty, because overlapping of ages and values. Pubertal development is determined by two events, genital and pubic hair development, that should be analyzed independently because one could be out of step with the other. The ultrasound (US) measurement of testicular volumes is the gold standard but is somewhat inconvenient, because it requires another procedure and, mainly, is costly.

The solution of the problems would be to determine testicular volumes matching US values, from the width of the testis obtained in the scrotum with a centimeter ruler, by formulas recently described, and to reference them to the stages of genital development.

Methods

The width and length of the testes in the scrotum with a centimeter ruler were obtained in 159 study subjects, in different stages of genital development and adults, for a total of 318 testicular determinations, from the age of 3 to 34 years. The width obtained in the scrotum was corrected by subtracting the values of the double scrotal skin (ss). The formulas were then applied and the testicular volumes matching US values were calculated. The volumes and the range of ages for different stages of genital development were determined. Penile measurements were obtained in 145 subjects and pubic and other hair recorded.

Paired and unpaired 2 tail student t-test was used to compare the means of the different groups expressed as means and SD and, in addition the Wilcoxon rank sum test and Bootstrap methods for the testicular volume groups. A p value of 0.05 or less was considered significant.

The Institutional Review Board (IRB) of Nationwide Children’s Hospital determined that this study did not require IRB approval.

Results

With a simple measurement of the width of the testis in the scrotum, with a centimeter ruler, testicular volumes matching US values were calculated and normative values for each stage of genital development were determined.

Conclusion

This information should solve present problems.

Electronic supplementary material

The online version of this article (doi:10.1186/s13633-017-0046-x) contains supplementary material, which is available to authorized users.

Scrotal testis size in unilateral non-palpable cryptorchidism, what it can and cannot tell: Study of a Middle Eastern population

BACKGROUND

Predicting the fate of a unilateral non-palpable testis based on its scrotal counterpart has been recommended by some, yet disputed by others, and the question remains open.

OBJECTIVE

To investigate the accuracy of contralateral testis hypertrophy in predicting the absence of a unilateral non-palpable testis in a Middle Eastern population.

STUDY DESIGN

This retrospective study included all patients referred to the present institution with unilateral non-palpable testis between June 2010 and August 2014, who had undergone laparoscopy. The scrotal testis was examined by sonography for size and volume, and diagnostic laparoscopy was utilized to determine the state of the cryptorchid testis.

RESULTS

Of the 135 referred patients, 64 were aged ≤8 years, 29 were 9-18 years, and 42 were >18 years old. Diagnostic laparoscopy revealed 63 intra-abdominal testes, 20 small intra-inguinal testes, 32 vanished testes, and 20 nubbins or aplasia (Summary fig.). Scrotal testis volume was only a modest predictor for absence of the contralateral gonad in adult patients in whom a 22 ml cut-off yielded 64.3% sensitivity and 92.9% specificity. For those aged <18 years, overall accuracy was poor and dropped below 60%. Relative enlargement of contralateral testis in decreasing order of size was observed in patients with primary monorchism, followed by those with secondarily atrophic or nubbin testis, and then those with normal sized inguinal or abdominal testis.

DISCUSSION

Unlike some previous series, which based their conclusions upon open exploration and mostly studied pre-pubertal subjects, the present results exclusively from laparoscopic exploration suggested that contralateral testis volume is a poor and inconsistent predictor of monorchism in children, and marginally predictive for young adults with unilateral non-palpable testis. This study comprised a reasonably large overall sample size compared with preceding reports; however, the number of patients within in each age group was limited. Greater numbers could allow for statistical comparison stratified by age group, for which this study was not powered.

CONCLUSION

Contralateral testis volume predicts, with modest accuracy, monorchism in adults with unilateral non-palpable testis. In younger patients, the overall predictive accuracy of scrotal testis size is poor and not consistently dependable.

Measurement of testicular volume in Wistar rats using a caliper and ultrasonography in experimental surgery

PURPOSE

To compare the measurement of the testicular volume of Wistar rats using a caliper and ultrasonography.

METHODS

Forty Wistar rats were randomly assigned into four groups. A tensile force of 1.6 Newton (N) and 1.0 N was applied to the right spermatic cord in group I and group II, respectively. Group III was the sham group, and group IV served as a control. The initial and final testicular volumes were measured using a caliper and ultrasonography and compared. A significance level of 5% was used.

RESULTS

The Kappa coefficient was equal to 0.292 (p = 0.006). The Pearson correlation coefficient obtained for the percent reduction in the right testicular volume using ultrasonography and a caliper was equal to 0.696 (p < 0.001).

CONCLUSION

There was reasonable agreement and a significant positive correlation between the percent reduction in the right testicular volume using ultrasonography and a caliper.

Testicular hypertrophy as a predictor for contralateral monorchism: Retrospective review of prospectively recorded data

OBJECTIVES

Testicular hypertrophy has previously been evaluated as a predictor of monorchism. However, its implication in clinical practice is not well evaluated. The aim of the present study was to examine its value in planning the operative time.

PATIENTS AND METHODS

Medical charts of prospectively recorded data of 76 consecutive patients with unilateral impalpable testis from 2011 to 2014 were reviewed at the present institute. Inclusion criteria included prepubertal patients with non-palpable testes by examination under anesthesia. Contralateral testes were prospectively measured using a Takihara orchidometer. Orchiectomy or orchiopexy was performed according to the viability of the undescended testis (UDT). Collected data included age of surgery, contralateral testicular size, surgical time and laparoscopic findings. A ROC curve was used to define the best cut-off volume of the contralateral testis that can predict ipsilateral testicular viability. The Student's t-test was used to examine if this cut-off volume would be useful in allocating the operative time.

RESULTS

Of 76 patients, four palpable testes by examination under anesthesia were excluded. The remaining 72 patients were included in the study. Ipsilateral normal viable testes were found in 26 (36.1%) patients, while 46 (63.9%) had non-viable testes (testicular nubbins or vanishing testes) (Figure). A contralateral testicular volume > 2 ml was significantly predictive for monorchism with 71.7% sensitivity and 100% specificity (P < 0.001). The mean operative time for management of UDT with a contralateral size >2 ml was 50 min, which was significantly shorter than that for UDT with a contralateral size ≤ 2 ml, which was 88 min (P < 0.001).

DISCUSSION

In previously published reports, the cut-off value for testicular hypertrophy that predicts monorchism greatly varied. This is likely due to the different methods used for testicular measurements that make it impractical to make a direct comparison. The usefulness of predicting monorchism before surgery has not previously been used as a guide for allocating operative time in the management of a unilateral non-palpable testicle. This study had some limitations, including a relatively small sample size and involvement of different surgeons, which may have affected the operative time.

CONCLUSION

Using the cut-off volume of a contralateral testis >2 ml as a predictor for monorchism can reduce the allocated operative time by approximately one third.

Accuracy of orchidometry in boys with varicocele

INTRODUCTION

Orchidometric evaluation of the testis has been proposed as a cost-effective alternative to measurement of the testis with high-frequency linear ultrasound, which may be costly in terms of hospital resources and patient time. It is known from animal experiments, autopsy series, and small clinical studies that, under ideal conditions, orchidometry may approximate ultrasound measurement. However, little is known of the effectiveness of orchidometry in the clinical setting in a large sample of adolescents with varicocele.

OBJECTIVE

We sought to analyze the performance characteristics of Rochester orchidometry and its agreement with ultrasound testis volumes in boys with varicocele.

STUDY DESIGN

Our institutional varicocele database was analyzed from March 2000 to May 2013, including all boys with Rochester orchidometric measurement and ultrasound-based volume measurement performed on the same day. The Lambert formula (L*W*H*0.71) was used to calculate ultrasound volumes. Seven-hundred and twenty measurements were included: 360 of the left testis, and 360 of the right testis. Each subject was included once; in the event of serial measurements the earliest measurement was analyzed. Bland-Altman plots with 95% limits of agreement were used to compare orchidometry and ultrasound measurements. Analysis was performed with JMP, v11 Pro.

RESULTS

Age at exam ranged from 11.2 to 18.5 years (median 15.8). With respect to varicocele grade, 183 (50.8%) were grade III, 113 (31.4%) were grade II, 42 (11.7%) were grade I, 12 (0.3%) were bilateral, and 10 (0.3%) were ungraded. Mean ultrasound left testis volume was 13.6 cc (SD 6.6) and mean right testis volume was 15.1 cc (SD 6.9). Eleven surgeons performed the orchidometric measurements; one surgeon performed 71% of the exams. Mean overestimation on the right was 2.0 cc (SD 4.2) and on the left was 1.9 cc (SD 4.1); each was highly statistically significant (p < 0.0001, paired t test). Error was correlated with testis size, implying a greater degree of overestimation with increasing volume (p < 0.01, Pearson's correlation 0.09). Amount of volume overestimation and variability was not significantly different for right and left testis. Sensitivity and specificity of Rochester orchidometry to detect a testis volume differential (TVD) of 20% were 33% (95% CI 23-42%) and 96% (95% CI 92-97%), respectively. Testis size, varicocele grade, or examining surgeon had no effect on sensitivity or specificity.

DISCUSSION

We have shown in a large series of boys with adolescent varicocele that in clinical practice there is a modest degree of overestimation of testis volume on average (1.9-2.0 cc), although there is a large range of volume estimation, such that the 95% confidence interval ranges are quite wide, from approximately 6 cc lower than the true volume to 10 cc greater than the true volume. Furthermore, the low sensitivity (33%) of orchidometry for 20% testis volume differential renders this a suboptimal screening tool for this clinical parameter, which has been shown to be associated with semen analysis outcomes. Knowledge of the performance characteristics of orchidometry is similarly important for research, as factors such as the prevalence of testis volume differential are then dependent on the modality of measurement. Lastly, that this was conducted over a long time course with several surgeons involved suggests that these data reflect real-world application of orchidometry.

CONCLUSIONS

Appropriate caution should be exercised when relying solely on orchidometric evaluation of the testis. Rochester orchidometry in general appears to overestimate testis size, and there is wide variability in the estimation. In clinical practice, the sensitivity of Rochester orchidometry is modest in detecting a 20% testis volume differential; this difference would be missed in approximately two out of three of boys screened with orchidometry alone.

Testicular volumes revisited: A proposal for a simple clinical method that can closely match the volumes obtained by ultrasound and its clinical application

Background

The testicular volumes obtained with the clinical methods, calculated using the ellipsoid equation W² x L x π/6, correlate with those obtained by ultrasound (US) and are useful clinically, but overestimate ultrasound values, mainly because of the inclusion of the scrotal skin and epididymis, have much variability, and may not be accurate or reproducible.

The US measurement is somewhat inconvenient, because it requires another procedure and, mainly, is costly.

It would be helpful to have a simple, low cost clinical method that approximates or closely matches the results obtained by ultrasound.

Formulas, equivalent to the ellipsoid equations, were developed to calculate testicular volumes with corrections of the width (W), length (L), and height (H) of the testis obtained in the scrotum to avoid the inclusion of the scrotal skin and epididymis.

Subjects & methods

The US observations in our hospital of the width, height, length, height/width, and length/width ratios and volumes of 110 testes from 55 children from 1 month to 17 ½ years of age were reviewed. Based on these observations and those reported by others, formulas to apply to the clinical measurements were developed to approximate the volumes obtained by ultrasound. The validity and accuracy of the formulas were determined. For the clinical application of the formulas, measurements of the width of the testis in the scrotum, with a centimeter ruler, were obtained in 187 study subjects in different stages of puberty and adults, for a total of 374 testicular determinations.

Results

The widths obtained in the scrotum were corrected by subtracting the values of the double scrotal skin. The formulas were then applied and the testicular volumes determined. The testicular volumes were then compared to the ultrasound values reported in hundreds of subjects by four different groups and statistically analyzed. The volumes obtained by the formulas (means ± SD) closely matched the volumes obtained by ultrasound.

Conclusion

A simple clinical method, based on the width of the testis obtained in the scrotum with a centimeter ruler, which can determine testicular volumes closely matching those reported by ultrasound, is proposed.

Testicular development in cynomolgus monkeys

The testes from 136 male cynomolgus monkeys were examined histopathologically in order to investigate the relationship between the development of spermatogenesis and testis weight, age, and body weight. At Grade 1 (immature), Sertoli cells and spermatogonia were the only cell classes in the testis. At Grade 2 (pre-puberty), no elongated spermatids were observed in the testis, although a few round spermatids and small lumen formation were observed. At Grade 3 (onset of puberty), all classes of germ cells were observed in the testis, although seminiferous tubule diameters and numbers of germ cells were small. Slight debris in the epididymis was observed in almost all animals. At Grade 4 (puberty), almost complete spermatogenesis was observed in the seminiferous tubules and it was possible to ascertain the spermatogenesis stage as described by Clermont, although tubule diameters and numbers of germ cells were small. There was less debris in the epididymis than at Grade 3. At Grade 5 (early adult), complete spermatogenesis was observed in the seminiferous tubules. At Grade 6 (adult), complete spermatogenesis in the seminiferous tubules and a moderate or large number of sperm in the epididymis were observed. Moreover, sperm analysis using ejaculated sperm was possible. Logistic regression analysis showed that testis weight is a good indicator of testicular maturity.

Morphometric examination for development of reproductive organs in male cynomolgus monkeys

We previously reported on a histological classification of cynomolgus monkey testis into six grades (1, immature; 2, prepuberty; 3, onset of puberty; 4, puberty; 5, early adult; 6, adult) based on spermatogenesis development. In this investigation, the accessory reproductive organs from the same animals underwent histomorphometric examination, in addition to being examined histologically and weighed, to evaluate relationships between these parameters and the six grades. Seminiferous tubule diameter increased corresponding to the testicular maturity grade and was notably increased at grade 6. Beginning from grade 3, increases in the areas of the ductus epididymis were noted, and reserved sperm was visible in the lumen. In the prostate, the glandular lumen area per unit area showed an increase beginning from grade 3 but no clear differences between grades 4 and 6; advanced development of epithelial height was observed at grade 6. In the seminal vesicle, development of the epithelial cell layer was markedly increased at grade 6. It was concluded that development of the male accessory reproductive organs began after reserved sperm was observed in the lumen of the ductus epididymis (grade 3) and that these organs were developed notably when the testis reached sexual maturity (grade 6).

A simple orchidometric method for the preliminary assessment of maturity status in male cynomolgus monkeys (Macaca fascicularis) used for nonclinical safety studies

INTRODUCTION

The identification and use of mature male non-human primates in nonclinical toxicology studies could be important for evaluating candidate drugs for which the profile of toxicity may differ depending on sexual maturity. This investigation sought to establish operational criteria to complement the current standard of histological evaluation for defining sexual maturity in male cynomolgus monkeys (Macaca fascicularis) used for toxicology studies, and to identify a practical non-invasive measure to select mature males for study.

METHOD

Retrospectively, the relationships between body weight, testicular weight and testis histology were established in control males (n=126) used in previous toxicology studies. Prospectively, testicular volumes were measured in-life by orchidometry using comparative scrotal palpation (n=23 males used for study), then compared to testicular weights measured at necropsy.

RESULTS

Consistent with previous literature, a weak relationship was observed between body weight and testicular weight. There was, however, a very good relationship between testicular weight and histological maturation level, which was based upon microscopic examination of testes, epididymides and prostates. Orchidometric measurement of testicular volume was found to be a reasonable predictor of testicular weight and served to rapidly select sexually mature males for study, and a total testicular volume (left and right combined) of >20 ml correlated with the histological appearance of maturity.

CONCLUSION

Based upon this preliminary exploratory study, the initial simple measurement of testicular volume by orchidometry may provide a non-invasive alternative approach for assessing the sexual maturity of male cynomolgus monkeys in research colonies or during toxicology studies that will require more thorough validation.

Reliability of 2D ultrasound measurements of testis size in dolphins taken under voluntary behavior

This study was undertaken to evaluate the reliability of two-dimensional (2D) ultrasound in measuring testis size in dolphins, in vivo, with the subject presenting for examination under voluntary or trained behaviour. The testes of five bottlenose dolphins (Tursiops aduncus) were measured once by two operators to test inter-operator variability (reproducibility) and repeatedly measured by the same operator to test intra-operator variability (repeatability). Ultrasound examinations for each test were conducted on the same day to avoid measurement variability due to time difference. The evaluation of reproducibility and repeatability were conducted on separate days. In the ultrasound examination, the length, circumference, depth and width of both testes of the animal were measured. To prevent bias, measurements were not communicated between the operators on-site and repeated measurements were masked. Results showed that both reproducibility and repeatability of all the testis measurements were high (>90%). Overall, measurement variability of the technique was found to be of a satisfactory level. Ultrasound is a useful imaging tool for routine long-term monitoring of the testes in this species of animals. Sources of error due to movements as a result of the subject being in the water during examinations were inevitable and must be taken into account.

The reliability of ultrasonographic measurements for testicular volume assessment: comparison of three common formulas with true testicular volume

The aim of this study was to determine the correlation of ultrasonographic estimates of testicular volume with true testicular volume and to compare the accuracy and precision of the three most commonly utilized formulas. A total of 15 patients underwent high-resolution ultrasonography (US) analysis for testicular volume before orchiectomy. Testicular volume was calculated using three common formulas: (1) length (L) x width (W) x height (H) x 0.52; (2) the empirical formula of Lambert: L x W x H x 0.71; and (3) L x W2 x 0.52. The actual volume of each removed testis was estimated directly by a water displacement method. Thus, four volume measurements were obtained for each of the 30 testes. The obtained data were analyzed by paired t-test and linear regression analysis. All three US formula measurements significantly underestimated the true testicular volume. The largest mean biases were observed with US formula 1, which underestimated the true volume by 3.3 mL (31%). US formula 2 had a smaller mean difference from the true volume, with an underestimation of only 0.6 mL (6%). Regression analysis showed that formulas 1 and 2 had better R2 values than formula 3. However, all three US formulas displayed a strong linear relationship with the true volume (R2= 0.872-0.977; P < 0.001). Among the commonly used US formulas, the empirical formula of Lambert (L x W x H x 0.71) provided better accuracy than the other two formulas evaluated, and better precision than formula 3. Therefore, the formula of Lambert is the optimal choice in clinical practice.

Comparison between ultrasonographic and caliper measurements of testicular volume in the dog

The aim of this study was to compare the accuracy of two methods used to clinically estimate testicular volume in the dog. Caliper and ultrasonographic measurements of testicular dimensions (length, width and height) of both testes were performed on 21 adult Beagles. Either measurement was taken in vivo over the scrotal skin and again in vitro after castration, excluding or including, when possible, the epididymis. In a sub-sample of 14 testes of 7 randomly selected dogs, the testicular volume was calculated by the formula of an ellipsoid: length (l)xwidth (w)xheight (h)x0.5236, and the empiric formula of Lambert: (l)x(w)x(h)x0.71. The calculated volumes were then compared to the actual ones, which were estimated by water displacement. For each measurement method, the formula that estimated more accurately the true testicular volume was, subsequently, applied to the calculation of the testicular volume of the remaining testes. The formula of ellipsoid estimated testicular volume more accurately when in vivo and in vitro caliper measurements and in vitro ultrasound measurements were performed. The formula of Lambert estimated testicular volume more accurately when in vivo ultrasound measurements were performed. The volumes calculated from the measurements of calipers over the scrotal skin overestimated true volumes, on average, by 69+/-27% (concordance correlation coefficient r(ccc)=0.49). By contrast, those calculated from the ultrasonography measurements were more accurate, overestimating the true volumes by 17+/-24% (rccc=0.81). Therefore, ultrasonography when the formula of Lambert is used is more accurate than caliper methods for the estimation of testicular volume in clinical practice and should be the method of choice.

Histological evidences suggest recommending orchiopexy within the first year of life for children with unilateral inguinal cryptorchid testis

OBJECTIVE

To determine the optimal timing for orchiopexy, we evaluated the histological parameters of the cryptorchid testis.

METHODS

We prospectively performed testicular biopsy in a total of 65 consecutive children with palpable unilateral inguinal cryptorchid testes. For controls, we used testicular histological slides from 15 age-matched children with testicular tumor. To investigate the fertility potential, we analyzed the parameters including mean tubular diameter (MTD), mean tubular fertility index (MTFI), germ cell count/tubule (GCC), Sertoli cell index (SCI) and interstitial fibrosis index (IFI).

RESULTS

The MTFI and GCC in children < or =1 years of age were significantly higher than those of other older age groups. The MTFI, GCC and IFI were significantly better in patients < or =2 years of age when compared to those of > 2 years. Compared to the controls, the MTFI and GCC in the patients were significantly worse in those aged > 2 years at surgical repair. In the < or =2-year age group, the MTFI and GCC of the cryptorchid testis showed a decreasing tendency with age, which were contrasting with the ascending curves in the control and the curves crossed at 1-2 years of age in each parameter.

CONCLUSIONS

To protect fertility potential, we recommend, orchiopexy should be performed within the first year of life, and no later than 2 years of age in patients with palpable inguinal cryptorchid testes.

Testicular volume measurement: comparison of ultrasonography, orchidometry, and water displacement

OBJECTIVES

To determine the accuracy of orchidometry and ultrasonography for measuring the testicular volume by comparing the resultant measurements with the actual testicular volume in humans.

METHODS

The testicular volume of 40 testes from 20 patients with prostate cancer (mean age +/- SD 74.5 +/- 7.5 years) was measured using the Prader orchidometer and ultrasonography before therapeutic bilateral orchiectomy. The ultrasound measurements of testicular volume were calculated using three formulas: length (L) x width (W) x height (H) x 0.52, L x W2 x 0.52, and L x W x H x 0.71. The actual testicular volumes were determined by water displacement of the surgical specimen.

RESULTS

The mean actual testicular volume of the 40 testes was 9.3 cm3 (range 2.5 to 23.0). A strong correlation was found between the testicular volume calculated by the three ultrasound formulas and the actual volume (r = 0.910 to 0.965, P <0.0001) and was stronger than the correlation with the Prader orchidometer (r = 0.818, P <0.0001). The smallest mean difference from the actual testicular volume was observed with the formula L x W x H x 0.71, which overestimated the actual volume by 0.80 cm3 (7.42%). The measurements using the Prader orchidometer correlated with the actual testicular volume and with the testicular volume calculated using the three ultrasound formulas (r = 0.801 to 0.816, P <0.0001). However, the orchidometer measurements had the largest mean difference from the actual testicular volume (6.68 cm3, 81.7%).

CONCLUSIONS

The results of this study have shown that measuring the testicular volume by ultrasonography is more accurate than by the Prader orchidometer, and the formula L x W x H x 0.71 was the most accurate for calculating the testicular volume.

Testicular Volume Measurements Using Prader Orchidometer Versus Ultrasonography in Patients with Infertility

OBJECTIVES

To compare the accuracy of testicular volume measurements with the Prader orchidometer versus ultrasonography.

METHODS

The volume of 938 testes in 469 men with infertility (mean age 35.8 years) was measured using a Prader orchidometer and by ultrasonography. The ultrasound testicular volumes were calculated using the formula length x width x height x 0.71. To compare any differences between the methods according to testicular size, the patients were divided into six groups according to the ultrasound-determined volume: less than 5, 5 to 10, 10 to 15, 15 to 20, 20 to 25, and 25 cm3 or more.

RESULTS

The mean volume by orchidometry and ultrasonography was 18.7 and 13.7 cm3 for the right testis and 18.0 and 12.5 cm3 for the left, respectively, and was significantly overestimated by orchidometry (P <0.0001; by 5.1 cm3 on the right and 5.5 cm3 on the left). The largest differences between methods were observed for volumes of 10 to 15 cm3 on the right and 5 to 10 cm3 on the left. The difference between the methods decreased as the ultrasound-determined volume increased (r = 0.636 on the right; r = 0.598 on the left testis). Nonetheless, the Prader orchidometric measurements showed a strong correlation with the ultrasound measurements (r = 0.707 on the right; r = 0.746 on the left).

CONCLUSIONS

The testicular volume estimated by Prader orchidometry correlated closely with the measurements by ultrasonography. However, the orchidometer overestimated the testicular volume, especially in small testes.

Inter/intra investigator variation in orchidometric measurements of testicular volume by ten investigators from five institutions

AIM

To perform quality control studies on testicular volume measurements for a multi-center epidemiological study of male reproductive function.

METHODS

We constructed a data matrix with a balanced assignment for 2 consecutive days by ten investigators (andrological career: 4-21 years) from five institutions and 12 male volunteers aged 20-26 years. Testicular volume was measured by Prader's orchidometer. A skilled technician also performed an ultrasound estimate of testicular volume.

RESULTS

A statistically significant inter-investigator variation was found for both testes (P < 0.05). In addition, there was a statistically significant investigator-by-volunteer interaction in testicular volume measurement (P < 0.01). However, there was no statistically significant difference in the two measurements performed on consecutive days for either testis. The testicular volumes for both the right and left testes as estimated by ultrasonography were smaller than results using the orchidometer. However, there was no statistical significance (P > 0.05). The difference in experiences of the investigators did not significantly correlate with accuracy of measurements in either testis.

CONCLUSION

The present study revealed significant differences in the results of estimation of testicular volume among the ten investigators, but intra-investigator variation was not considerable. Improved training and proper standardization of the measurement will be necessary before starting a multi-center study based on an andrological examination.

Usefulness and limitation of punched-out orchidometer in testicular volume measurement

AIM

To determine the limitations of a punched-out orchidometer in practical use, we compared with a scrotal ultrasound (USG).

METHODS

A total of 281 testes from 142 males were examined using both a punched-out orchidometer and a USG. The volume differential between both methods was calculated and expressed as orchidometer/USG volume (O/U ratio). Distribution of the O/U ratio was determined and subdivided by clinical or pathological diagnosis. The correlations between the O/U ratio and patient age or orchidometer results were assessed.

RESULTS

There was a significant linear relationship between the results of orchidometer and USG (r=0.94, P <0.0001). The relationship between the O/U ratio and age or testicular volumes showed significant inverse correlations (r=0.22, P=0.0002, r=0.45, P <0.0001, respectively). Klinefelter's syndrome, ipsilateral detorted testes and hypogonadotropic hypogonadism comparatively showed a high O/U ratio. No incidental lesion was detected by USG necessitating treatment.

CONCLUSION

The punched-out orchidometer gives estimates that correlated well with the USG measurements and provides enough information for routine andrological evaluation. We should be aware that the orchidometer often overestimates the testicular volume, especially for the patients with small testis or adolescents.

Impact of varicocele on testicular volume in young men: significance of compensatory hypertrophy of contralateral testis

PURPOSE

We examined the impact on ipsilateral testicular volume in young men with varicocele and determined whether compensatory hypertrophy exists.

MATERIALS AND METHODS

Between April and November 2001, 2,700 men who were 20 years old and dwelling in the community were randomly selected at a 10% sampling fraction after a sampling process according to census district. A total of 2,080 men (77% response rate) agreed to participate in the study. All volunteers underwent standard evaluation, including medical history and physical examination.

RESULTS

Testicular volume on the affected side in men with varicocele was significantly smaller than that of the contralateral side, while testicular volume on the contralateral side was significantly larger than that of the left side in normal men. In those with unilateral varicocele testicular volume on the affected side did not depend on varicocele grade but contralateral testicular volume in men with grade I varicocele was significantly smaller than in men with higher grades of the entity. The rate of testicular atrophy increased depending on varicocele grade.

CONCLUSIONS

Varicocele negatively impacts testicular volume on the affected side in young men. Our findings suggest that men with higher grades of varicocele have a hypertrophied testis on the contralateral side.

Does contraction of mesh following tension free hernioplasty effect testicular or femoral vessel blood flow?

Prosthetic mesh can contract by 20-75% of its original size within ten months after implantation. We set out to determine whether this contraction has any effect on testicular or femoral vessel blood flow following open or laparoscopic hernia repair. Twenty patients who underwent mesh repair of a primary unilateral inguinal hernia repair by Open (10) or Laparoscopic (10) methods a median of 3 years previously were investigated by ultrasound to determine the haemodynamic characteristics of the testis and femoral vessels. There was no significant difference in testicular blood flow, volume or echogenicity between the different types of repair or the contralateral side. The vertical and transverse dimensions of the femoral artery and vein were similar in all groups as was blood flow. Mesh contraction following inguinal hernioplasty does not adversely affect the testis or femoral vessels and can be used safely for both anterior and preperitoneal approaches.

Inter-observer variation in the results of the clinical andrological examination including estimation of testicular size

Inter-observer variation in andrological examination by 10 clinical investigators from five Nordic and Baltic countries was investigated. In addition, information on intra-observer variation was obtained for six of the 10 investigators. Testicular size was measured using Prader's orchidometer and one of the investigators also performed an ultrasound estimate of testicular size. A highly significant difference (p < 0.001) between observers was found with an inter-observer error of 16% in estimating testicular size in 23 young men. The difference in the estimate tended to increase with increasing testicular size. There was no significant intra-observer difference in two measurements performed on consecutive days. Only differences in median testis size, which were greater than 31% between measurements by two investigators, were found to be significant at the 5% level. The ultrasound estimate of testicular size was significantly lower than the orchidometer estimate, with a mean difference of 3.6 mL for the left testis and 4.3 mL for the right testis. Tanner staging of genitalia and diagnosis of a varicocele was subject to great inter-observer variation, and for the diagnosis of varicocele only one-third of the investigators was able to reproduce their results on a second examination. In conclusion, it was found that the clinical andrological examination of young men is subject to great inter-observer variation. This should be kept in mind when results from different studies are compared as well as in daily clinical practice.

Gonadal and sexual function in men treated for childhood cancer

BACKGROUND

Insofar as a majority of children with malignant diseases are cured, the late effects of treatment are of major importance.

PROCEDURE

A retrospective study was conducted of gonadal and sexual function of 77 adult male survivors of childhood malignancies treated and cured at a single center from 1970 to 1989 and followed for a median of 13 years. The study included an interview, physical examination, sperm test, and hormonal analyses.

RESULTS

One-third of the patients were treated for hematological malignancies, one-third for CNS tumors, and one-third for other malignancies. Eleven patients required androgen substitution after treatment for tumors of the pituitary-hypothalamic region or acute lymphoblastic leukemia including testicular irradiation and/or orchiectomy. In three patients the testicles were removed. The other eight had small testicles, and those providing sperm samples had azoospermia, and sexual function was disturbed in most of them. Most of the remaining 66 patients had small testicles. Normozoospermia was found in 63%, oligozoospermia in 20%, and azoospermia in 17%. Although there was a highly significant correlation between testicular volume and sperm test, 25% of patients with testicles of <10 ml had normozoospermia. Sexual function was normal in 46 patients, and they were married at a frequency comparable to the normal population. Twenty-one patients had no signs of gonadal dysfunction.

CONCLUSIONS

Patients treated for tumors in the hypothalamic-pituitary region or treated with testicular irradiation or with high doses of alkylating agents had severe gonadal and sexual dysfunction. Most of the other patients had good prospects for preserved gonadal and sexual function.

Effect of adult microsurgical varicocelectomy on testicular volume

OBJECTIVES

To re-examine the potential influence of varicocelectomy on testicular volume using scrotal ultrasonography, because it has been reported that total testicular volume (assessed by physical examination) increases after adult varicocele ligation.

METHODS

A retrospective review of the testicular volume and semen parameters of 61 men who underwent microsurgical varicocelectomy between 1996 and 1998 was performed. Ultrasound-derived testicular volumes and total motile sperm counts were compared before varicocelectomy and at a mean of 7.2 months postoperatively.

RESULTS

Bilateral varicocelectomy was performed in 22 men; 39 men underwent a left-sided procedure only. Overall, no significant change was found in the mean total testicular volume after varicocelectomy compared with preoperatively (24.0 versus 23.9 mL, respectively; P = 0.74). Similarly, the testicular volumes did not change significantly after left or bilateral varicocelectomy (P >0.05). Overall, the mean total motile sperm count increased significantly after varicocelectomy (17. 9 to 25.4, P = 0.05).

CONCLUSIONS

This was the first study to examine the effect of adult varicocelectomy on testicular volume using ultrasound-derived measurements of volume. Unlike previous findings, our data suggest that although adult varicocelectomy improves semen quality in most infertile men, it does not result in a significant increase in testicular volume.

Loss of left testicular volume in men with clinical left varicocele: correlation with grade of varicocele

It is reported that a clinical left varicocele is associated with loss of ipsilateral testicular volume. We have examined the loss of left testicular volume in infertile men with clinical left varicocele using ultrasound-derived measurements of testicular volume. We have reviewed the testicular volumes, maximum internal spermatic vein diameters, and the clinical reports of 404 men presenting for infertility evaluation at our institution between 1992 and 1996. Men with bilateral or subclinical varicoceles were excluded from the study. Subclinical varicoceles were diagnosed by the ultrasonographic demonstration of one or more veins having a maximal diameter of more than 3 mm. In men with clinical left varicocele, mean left testicular volume was less than right testicular volume (12.7 vs. 13.8 mL, P < .001). This finding was not observed in men without varicocele (12.3 vs. 12.6 mL, P > .05). In men with left varicocele, the difference between right and left testicular volume (right minus left) increased with increasing varicocele grade. Our data demonstrate that a left varicocele is associated with loss of left testicular volume. The results also show that the degree of left testicular hypotrophy is proportional to the clinical grade of the varicocele.

The influence of clinical and subclinical varicocele on testicular volume

OBJECTIVE

To examine the possible loss of testicular volume in infertile men with clinical and subclinical varicocele by using ultrasound (US)-derived measurements of testicular volume.

DESIGN

Retrospective review of clinical and scrotal US reports.

SETTING

University infertility clinic.

PATIENT(S)

Infertile men (n = 404) presenting for evaluation from 1992 to 1996.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Presence of clinical or subclinical varicocele, US-derived measurements of testicular volume.

RESULT(S)

In men with clinical left or subclinical left varicocele, left testicular volume was significantly less than right testicular volume (12.9 versus 14.1 and 13.2 versus 14.7 mL, respectively). This finding was not observed in men with bilateral clinical or bilateral subclinical varicoceles or in men without varicocele.

CONCLUSION(S)

Our data confirm previous reports showing that a clinical left varicocele can negatively impact on left testicular volume and for the first time show that a subclinical varicocele is also associated with decreased left testicular volume.