Advanced ultrasound techniques in small animal reproduction imaging.

Ultrasonography is the imaging technology of choice for the evaluation of the reproduction system and of pregnancy in both humans and animals. Over the past 10 years, there have been significant technological improvements of the equipment, while new technologies have been developed. Doppler, contrast-enhanced ultrasonography, elastography, and 3D/4D ultrasonography are advanced ultrasound techniques that have been designed as methods to increase the diagnostic sensitivity of two-dimensional (b-mode) ultrasound, and not as stand-alone tests. The basic physics as well as the advantages and limitations of these advanced ultrasound methods are briefly described. In the reproductive diagnostics of small animals, these techniques have gained an increased popularity as proved by the increased publication of several reports that are also briefly summarized in this review. Clinical applicability is to date limited because of a lack of research on the diagnostic value in concrete situations. Future research projects should focus also on standardization of the used techniques, on determination of thresholds to discriminate between healthy or diseases or fertile versus infertile and on the predictive value of advanced ultrasound findings. Continuing development and optimization of different ultrasound techniques as well as the increase of related scientific interest and worldwide research promises that the clinical interest on the use of advanced ultrasound techniques will increase in future.

Examination of jackass (Equus asinus) accessory sex glands by B-mode ultrasound and of testicular artery blood flow by colour pulsed-wave Doppler ultrasound: Correlations with semen production.

The accessory sex glands play a major role in the production of seminal plasma, and testicular artery blood flow seems to strongly influence testicular function. However, very little ultrasound imaging of these organs has been undertaken in donkeys. The present work reports the results of such examinations in five jackasses along the year. The accessory glands were inspected by B-mode ultrasound while the testicular artery blood flow was assessed by colour pulsed-wave Doppler ultrasound. The testicular artery was examined at pampiniform plexus (PPT), supratesticular area (ST) and capsular artery (CA). Values were recorded for the total arterial blood flow (TABF), peak systolic velocity (PSV), end-diastolic velocity (EDV), resistive index (RI), pulsatility index (PI) and time average maximum velocity (TAMV). Semen was obtained and assessed for sperm concentration, viability, abnormalities and motility using a CASA system. The bulbourethral glands, prostate and ductus deferens ampullae were relatively larger than in the stallion. Bulbourethral glands and ampullae sizes were inversely correlated with sperm motility. An reduction in blood flow between the level the PPP and the CA was observed, helping to reduce testis temperature and oxygen pressure. Blood flow at the CA showed the strongest correlation with semen production. PI and RI were positively correlated with the CASA motility variable STR (p = .02, p = .06) and sperm viability (p = .01), while sperm concentration (p = .05) correlated inversely with PSV, EDV, TAMV and TABF. EDV also correlated negatively with the CASA variables VSL, LIN, STR and VAP (p ≤ .05). PI and RI were also negatively correlated with testis length (p = .0093, p = -.0438).

Surgical treatment and outcome of complete unilateral urinary tract duplication in a dog.

OBJECTIVE: To report the surgical technique and outcome for correction of complete unilateral duplication of the left urinary tract in a dog. ANIMALS: One 7-month-old entire male Jack Russell terrier. STUDY DESIGN: Case report METHODS: A dog was referred for investigation because of urinary incontinence (UI), preputial irritation (pruritus), diphallia, and cryptorchidism. Computed tomography including urethrographic studies revealed a left duplex kidney, double ectopic left ureters, and a duplex urinary bladder comprising two halves separated by a median septum, each of which emptied into a separate urethra which coursed through separate penises. The left testis was abdominally retained. The right upper urinary tract was considered normal, and the right testis was within the scrotum. Left sided ureteronephrectomy was performed, the median bladder septum was ablated, and the left urethra was ligated. The left penis was partially amputated, and the dog was castrated. RESULTS: Urinary incontinence was improved but persisted after surgery. After repeat imaging, revision surgery was performed 3 months later in which the distal stumps of the (left) ectopic ureters were found to be filling with urine from the right urethra. Urinary incontinence resolved after resection of these ureteric stumps from the prostate and complete transection of the left urethra. CONCLUSION: Extensive surgery with resection and correction of urinary tract duplication was successful in resolving UI in this case. Urogenital duplication should be considered a rare cause of UI. The presence of external congenital deformity (eg, diphallia) should alert clinicians to the possibility of significant concurrent internal abnormalities.

MRI of the Male Pelvic Floor.

The pelvic floor is a complex structure that supports the pelvic organs and provides resting tone and voluntary control of the urethral and anal sphincters. Dysfunction of or injury to the pelvic floor can lead to gastrointestinal, urinary, and sexual dysfunction. The prevalence of pelvic floor disorders is much lower in men than in women, and because of this, the majority of the published literature pertaining to MRI of the pelvic floor is oriented toward evaluation of the female pelvic floor. The male pelvic floor has sex-specific differences in anatomy and pathophysiologic disorders. Despite these differences, static and dynamic MRI features of these disorders, specifically gastrointestinal disorders, are similar in both sexes. MRI and MR defecography can be used to evaluate anorectal disorders related to the pelvic floor. MRI can also be used after prostatectomy to help predict the risk of postsurgical incontinence, to evaluate postsurgical function by using dynamic voiding MR cystourethrography, and subsequently, to assess causes of incontinence treatment failure. Increased tone of the pelvic musculature in men secondary to chronic pain can lead to sexual dysfunction. This article reviews normal male pelvic floor anatomy and how it differs from the female pelvis; MRI techniques for imaging the male pelvis; and urinary, gastrointestinal, and sexual conditions related to abnormalities of pelvic floor structures in men.Online supplemental material is available for this article.©RSNA, 2019.

How can schistosome circulating antigen assays be best applied for diagnosing male genital schistosomiasis (MGS): an appraisal using exemplar MGS cases from a longitudinal cohort study among fishermen on the south shoreline of Lake Malawi.

We provide an update on diagnostic methods for the detection of urogenital schistosomiasis (UGS) in men and highlight that satisfactory urine-antigen diagnostics for UGS lag much behind that for intestinal schistosomiasis, where application of a urine-based point-of-care strip assay, the circulating cathodic antigen (CCA) test, is now advocated. Making specific reference to male genital schistosomiasis (MGS), we place greater emphasis on parasitological detection methods and clinical assessment of internal genitalia with ultrasonography. Unlike the advances made in defining a clinical standard protocol for female genital schistosomiasis, MGS remains inadequately defined. Whilst urine filtration with microscopic examination for ova of Schistosoma haematobium is a convenient but error-prone proxy of MGS, we describe a novel low-cost sampling and direct visualization method for the enumeration of ova in semen. Using exemplar clinical cases of MGS from our longitudinal cohort study among fishermen along the shoreline of Lake Malawi, the portfolio of diagnostic needs is appraised including: the use of symptomatology questionnaires, urine analysis (egg count and CCA measurement), semen analysis (egg count, circulating anodic antigen measurement and real-time polymerase chain reaction analysis) alongside clinical assessment with portable ultrasonography.

Prostatic utricles without external genital anomalies in children: our experience, literature review, and pooling analysis.

BACKGROUND: It has been recognized that the incidence of prostatic utricle in boys is increasing and is closely associated with diseases such as hypospadias. However, the clinical features of prostatic utricle with normal external genitalia have received little attention. METHODS: Based on this, a series of 22 male children with prostatic utricles has been compiled by adding our 3 patients to 19 cases reported. All children enrolled had normal external genitalia. Clinical data of the case was reviewed. RESULTS: Urinary tract infection, purulent urethral discharge and pyuria were the most common presenting chief complaint (41%), irritative lower urinary tract symptoms were present in 17% of cases, obstructive lower urinary tract symptoms were noted in 14%. Urinary retention has been reported in 18% and epididymitis has been reported in 14%. Relatively rare clinical symptoms are abdominal pain, hematuria, and hematospermia. A case of calculus formation and a case of neoplasia within the prostatic utricle has been reported. A cystic mass found by digital rectal examination is the most common presenting sign. A utricular lesion posterior to the bladder was revealed by imaging examination. Unilateral renal agenesis was associated in 32% of reports. Non-surgical approach was chosen in 3 cases, transrectal ultrasonography guided aspiration has been reported in 1 case. Endoscopic techniques were used in 3 cases. Open excision was used in 11 cases. The laparoscopic excision was chosen in 3 cases and Robot-assisted laparoscopy was reported in 1 case. Symptoms and signs disappeared after treatment in all children, and no recurrence occurred during follow-up. CONCLUSIONS: Prostate utricles without external genital anomalies are rarely reported in children, and are easily missed and misdiagnosed, often accompanied by recurrent urinary tract infections, lower urinary tract symptoms, epididymitis, dysuria and other symptoms. Imaging studies can confirm the diagnosis. Symptomatic and large utricles should be actively treated. The treatment program should be based on the age, clinical symptoms, and size and location of the utricle.

Scrotal emergencies: An imaging perspective.

Acute scrotal pain is a common complaint in emergency or primary care practice. A myriad of pathologies need to be considered, and while the clinical history often leads the clinician to the correct diagnosis, radiologists are often called upon to provide further diagnostic information through ultrasonography. Here, we present the sonographic features of various scrotal emergencies, as well as a few pitfalls. Through this, we explore the breadth of urgent pathologies that may be encountered, both traumatic and non-traumatic. For the clinician who performs point-of-care ultrasound, whether in clinic or in the emergency department, we hope that this pictorial article will lay a good foundation for confident and accurate image interpretation.

Prenatal Anogenital Distance Is Shorter in Fetuses With Hypospadias.

OBJECTIVES: Recent research provides evidence that anogenital distance may serve as a novel metric to assess reproductive potential in men. In children, a shorter anogenital distance was linked with cryptorchidism, hypospadias, and micropenis. Scarce data exist in the literature regarding anogenital distance measurement in the fetus. The aim of our study was to assess whether intrauterine measurement of fetal anogenital distance could assist in the differential diagnosis of male genital anomalies. METHODS: Anogenital distance was prospectively measured in all cases referred for suspected isolated abnormal male genitalia. Final diagnoses, confirmed by a pediatric urologist, were compared with anogenital distance prenatal measurements. RESULTS: Fifty-two cases were referred for evaluation because of suspected male external genital malformation during a 12-month period. Cases with normal-appearing genitalia, associated major malformations, and early severe fetal growth restriction were excluded from the study. Postnatal examination revealed 14 cases of hypospadias in varying severity and 8 cases of a buried penis. All fetuses with hypospadias had an anogenital distance measurement below the fifth percentile. Statistical analysis revealed a significant difference between the normal mean anogenital distance for gestational age versus those with hypospadias (mean ± SD, 16.90 ± 4.08 and 11.68 ± 3.31 mm, respectively; P = .001). No significant difference was found between the normal mean anogenital distance for gestational age versus those with a buried penis (18.85 ± 2.76 and 19.46 ± 3.41 mm; P = .700). CONCLUSIONS: Fetuses with hypospadias have a statistically significant shorter anogenital distance compared with the general population. Therefore, anogenital distance may serve as a complementary objective sonographic parameter in the prenatal assessment and counseling of male external genital anomalies.

Is thyroid hormones evaluation of clinical value in the work-up of males of infertile couples?

STUDY QUESTION: Is thyroid hormones (TH) evaluation of clinical value in the work-up of males of infertile couples? STUDY ANSWER: Our results suggest that TH evaluation is not mandatory in the work-up of male infertility. WHAT IS KNOWN ALREADY: A few previous studies performed on a limited series of subjects reported a negative impact of hyper- and hypo-thyroidism on semen volume, sperm concentration, progressive motility and normal morphology. No previous study has systematically evaluated associations between TH variation, semen parameters and ultrasound characteristics of the male genital tract. STUDY DESIGN, SIZE AND DURATION: Cross-sectional analysis of a consecutive series of 172 subjects seeking medical care for couple infertility from September 2010 to November 2014. PARTICIPANTS/MATERIALS, SETTING, METHODS: Of the entire cohort, 163 men (age 38.9 ± 8.0 years) free of genetic abnormalities were studied. All subjects underwent a complete andrological and physical examination, biochemical and hormonal assessment, scrotal and transrectal colour-Doppler ultrasound (CDUS) and semen analysis (including seminal interleukin 8 levels, sIL-8) evaluation within the same day. MAIN RESULTS AND THE ROLE OF CHANCE: Among the patients studied, 145 (88.9%) showed euthyroidism, 6 (3.7%) subclinical hyper- and 12 (7.4%) subclinical hypo-thyroidism. No subjects showed overt hyper- or hypo-thyroidism. At univariate analysis, no associations among thyroid-stimulating hormone (TSH) or TH levels and sperm parameters were observed. Conversely, we observed positive associations among free triiodothyronine (fT3) and free thyroxine (fT4) levels, ejaculate volume and seminal fructose levels. In a multivariate model, after adjusting for confounders such as age, body mass index, smoking habit, sexual abstinence, calculated free testosterone, prolactin and sIL-8 levels, only the associations found for fT3 levels were confirmed. When CDUS features were investigated, using the same multivariate model, we found positive associations between fT3 levels and seminal vesicles (SV) volume, both before and after ejaculation (adj. r = 0.354 and adj. r = 0.318, both P < 0.0001), as well as with SV emptying (ΔSV volume; adj. r = 0.346, P < 0.0001) and echo-texture inhomogeneity. In addition, after adjusting for confounders, negative associations between fT4 levels and epididymal body and tail diameters were found. No significant associations between TSH or TH levels and CDUS features of other organs of the male genital tract, including testis and prostate, were found. Finally, when the features of subjects with euthyroidism, subclinical hypo- and hyper-thyroidism were compared, no significant differences in seminal or hormonal parameters were found. Conversely, evaluating CDUS parameters, subjects with subclinical hyperthyroidism showed a higher difference between the SV longitudinal diameters measured before and after ejaculation when compared with that of subclinical hypothyroid men, even after adjusting for confounders (P < 0.007). All the other male genital tract CDUS characteristics did not differ among groups. LIMITATIONS, REASONS FOR CAUTION: First, the number of patients investigated is relatively small and those with (subclinical) thyroid dysfunctions are an even smaller number; hence, it is therefore difficult to draw firm conclusions. Moreover, the present results are derived from patients consulting an Italian Andrology Clinic for couple infertility, and could have different characteristics from the male general population or from those males consulting general practitioners for reasons other than couple infertility. Finally, due to the cross-sectional nature of the study, neither a causality hypothesis nor mechanistic models can be inferred. WIDER IMPLICATIONS OF THE FINDINGS: Although no associations between TH and sperm parameters were observed, present data support a positive effect of TH on SV size and a permissive role on the ejaculatory machinery, likely through an action on SV and epididymal contractility. This is the first study reporting such evidence. However, in contrast with the view that TH assessment is important for female fertility, our results do not support a systematic evaluation of thyroid function in males of infertile couples. How TH abnormalities impact male fertility needs to be addressed by further studies. STUDY FUNDING/COMPETING INTERESTS: No funding was received for the study. None of the authors have any conflict of interest to declare.

Inguinoscrotal Pathology on Computed Tomography: An Alternative Perspective.

Computed tomography (CT) is not the imaging technique of choice to assess inguinoscrotal pathology, as magnetic resonance or ultrasonography have superior soft tissue contrast resolution and do not involve gonadal exposure to ionizing radiation. However, testicular and inguinoscrotal pathology may be found both as an extension of intra-abdominal processes or incidentally on CT scans requested for other reasons. CT also plays a role in the evaluation of testicular injury when associated to pelvic trauma and in perineal infections with scrotal extension. A pictorial review of testicular and inguinoscrotal involvement in vascular, neoplastic, traumatic, infectious, or inflammatory diseases and in complications of abdominal surgeries is presented. Additionally, the CT appearance of several congenital anomalies and benign processes is depicted.

Compared with feeding infants breast milk or cow-milk formula, soy formula feeding does not affect subsequent reproductive organ size at 5 years of age.

BACKGROUND: Literature reports suggest that phytochemicals, such as isoflavones found in soybeans, impair reproductive function in animals and raise the possibility that consuming soy infant formula could alter hormonally sensitive organ development in children. OBJECTIVE: This study compared reproductive organs volumes and structural characteristics in children at age 5 y who were enrolled in the Beginnings study long-term cohort. METHODS: Breast bud, uterus, ovaries, prostate, and testes volumes and characteristics were assessed by ultrasonography in 101 children (50 boys and 51 girls) aged 5 y who were breastfed (n = 35) or fed cow-milk formula (n = 32) or soy formula (n = 34) as infants. Analyses were adjusted for race, gestational age, and birth weight. RESULTS: Among girls, no significant differences were found in breast bud, ovarian, or uterine volumes; counts of ovaries with cysts; ovarian cysts numbers; ovarian cyst size; and uterine shape between the diet groups. Among boys, no significant differences were found in breast bud, testes, or prostate volumes or structural characteristics between the diet groups. CONCLUSIONS: In this cohort, no early infant feeding effects were found on reproductive organs volumes and structural characteristics in children age 5 y. The follow-up of these children through puberty is planned and should help delineate potential early infant feeding effect on reproductive function later in life.

Anogenital distance in male and female fetuses at 20 to 35 weeks of gestation: centile charts and reference ranges.

OBJECTIVES: In pediatrics, anogenital distance (AGD) serves as a bioassay of normal phenotypic androgen action on the external genitalia. Recently, hypospadias and cryptorchidism were reported to be associated with reduced AGD. No normal reference ranges exist for fetuses throughout gestation. This study defines the normal centile chart of the AGD, in male and female fetuses, between 20 and 35 weeks of gestation. METHODS: Participants were low-risk pregnant women, 20 to 35 weeks of gestation. All fetuses were singleton, with normal anatomic scan and appropriate fetal biometry for gestational age. Fetal AGD was measured by transabdominal ultrasound. The perineum was assessed in the axial plane. The distance was measured from the center of the anus to the posterior convergence of the fourchette in female fetuses and to the posterior base of the scrotum in male fetuses. Statistical analysis included the construction of the normal, modeled, centile, and standard deviation range, for each gestational age. Intraobserver and interobserver variability was assessed by the interclass correlation and Bland-Altman plot. RESULTS: Adequate measurements were obtained for 218 female and 206 male fetuses. For 17 cases, measurements were not possible because of fetal lie. AGD increased linearly throughout gestational age (GA) (r(2) = 0.808) for both sexes and was expressed by the following regression equation: for male fetuses, -12.348 + 1.075*GA, and for female fetuses, -3.179 + 0.513*GA, where GA is gestational age. The normal centiles, means, and standard deviations, per week, are presented. CONCLUSION: AGD measurement in utero is feasible. These measurements assess the normality of the perineal region and may assist in the detection of genital anomalies.

MicroCT analysis unveils the role of inflatable female genitalia and male tibial complex in the genital coupling in the spider genus Aysha (Anyphaenidae, Araneae).

Sperm transfer in spiders is achieved by copulatory organs on the male pedipalps (i.e., copulatory bulbs), which can be simple or a complex set of sclerites and membranes. During copulation, these sclerites can be used to anchor in corresponding structures in the female genitalia by means of hydraulic pressure. In the most diverse group of Entelegynae spiders, the retrolateral tibial apophysis clade, the female role in the coupling of genitalia is considered rather passive, as conformational changes of the female genital plate (i.e., the epigyne) during copulation are scarce. Here, we reconstruct the genital mechanics of two closely related species belonging to the Aysha prospera group (Anyphaenidae) that bear a membranous, wrinkled epigyne and male pedipalps with complex tibial structures. By using microcomputed tomography data of a cryofixed mating pair, we reveal that most of the epigyne remains greatly inflated during genital coupling, and that the male tibial structures are coupled to the epigyne by the inflation of a tibial hematodocha. We propose that a turgent female vulva is a prerequisite for the genital coupling, which could implicate a female control device, and that the structures from the male copulatory bulb have been functionally replaced by tibial structures in these species. Furthermore, we show that the conspicuous median apophysis is maintained in spite of being functionally redundant, posing a puzzling situation.

Semen apoptotic M540 body levels correlate with testis abnormalities: a study in a cohort of infertile subjects.

STUDY QUESTION: What are the associations between semen apoptotic M540 bodies and other parameters of semen quality and sonographic alterations of the male genital tract in a cohort of infertile subjects? SUMMARY ANSWER: In infertile subjects, semen M450 bodies are highly correlated with ultrasound and clinical signs of testis abnormalities but not with alterations of other parts of the male genital tract, suggesting a testicular origin of M540 bodies. WHAT IS KNOWN ALREADY: We have reported the presence in semen of round anucleate elements, named 'M540 bodies', resembling apoptotic bodies as they contain several apoptotic markers. STUDY DESIGN AND SIZE: A consecutive series of 130 males with couple infertility were evaluated, during the same day session, for clinical, scrotal and transrectal color-Doppler ultrasound characteristics, and hormonal and semen parameters, including interleukin 8 (sIL-8) and M540 body levels. PARTICIPANTS/MATERIALS, SETTING METHODS: Semen parameters were analyzed by WHO recommended procedures. CDU was performed using the ultrasonographic console Hitachi H21. sIL-8 and serum hormones were evaluated by ELISA methods. MAIN RESULTS AND THE ROLE OF CHANCE: The average percentage value of M540 bodies was 24.6 ± 18.3. After adjusting for possible confounders (age, waist, calculated free testosterone and smoking habit), M450 body levels negatively correlated with sperm number/ejaculate, progressive motility, normal morphology and sIL-8 levels (adj.r = -0.455, P < 0.0001; adj.r = -0.464, P < 0.0001; adj.r = -0.430, P < 0.001; adj.r = -0.236, P < 0.05, respectively). In a subset of patients with a history of cryptorchidism (n = 8), M540 bodies were higher than in non-cryptorchid men (40.5 ± 14.8 versus 23.6 ± 18.2%; P < 0.02). A negative correlation was found between M540 and ultrasound testis volume (adj.r = -0.241, P < 0.05), whereas a positive association was found with testis inhomogeneity [HR = 1.06 (1.02-1.09); P = 0.002], hypoechogenicity [HR = 1.05 (1.01-1.08); P < 0.02] and FSH levels (adj.r = 0.309, P < 0.01). No relationships were found with CDU characteristic of the prostate, seminal vesicles, epididymis and vas deferens. In a multivariate model, testis inhomogeneity and history of cryptorchidism were independently associated with M540 body levels (adj.r = 0.355, P < 0.01 and adj.r = 0.223, P < 0.05, respectively). Receiver operating characteristic analysis demonstrated that at the threshold of 27%, M540 bodies discriminate subjects with testis inhomogeneity with a sensitivity of 72% and specificity of 73%. LIMITATIONS, REASONS FOR CAUTION: The increased M540 body semen levels in men with a history of cryptorchidism should be confirmed in a larger number of patients. WIDER IMPLICATIONS OF THE FINDINGS: M540 bodies may be considered a semen marker of altered testis function and thus their evaluation may be helpful in the diagnosis of male infertility. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by grants from Ministry of University and Scientific Research (Prin project to E.B. and FIRB project to S.M.) and Regione Toscana (to G.F.).

Male genital abnormalities in intrauterine growth restriction.

OBJECTIVE: Previous studies have shown a correlation between hypospadias and intrauterine growth restriction (IUGR), suggesting an association between placental insufficiency and abnormal genital development. This study sought to analyze the association of IUGR and genital abnormalities apparent on fetal magnetic resonance imaging (MRI). METHODS: This retrospective study included 22 MRI scans of 20 male fetuses between 20 and 35 weeks of gestation presenting with IUGR. On MRI, penile length and testicular descent were evaluated. Student's t-testing and analysis of covariance were used to compare MRI penile length measurements with published normative data obtained from fetal ultrasonography (US) and MRI. McNemar testing was used to evaluate testicular descent in IUGR, compared with reported fetal MRI normative data. RESULTS: The penile length in IUGR fetuses was shorter than in normal fetuses (p<0.001). Furthermore, six of 20 fetuses presented with a micropenis (2.5 SD below the mean value for age). Undescended testes were significantly more frequent in IUGR fetuses than in normal fetuses (p=0.004). CONCLUSION: Our data confirm that abnormal fetal growth may be associated with penile shortening and, potentially, also undescended testes.

Assessing Anatomical Changes in Male Reproductive Organs in Response to Larval Crowding Using Micro-computed Tomography Imaging.

Ecological conditions shape (adaptive) responses at the molecular, anatomical, and behavioral levels. Understanding these responses is key to predict the outcomes of intra- and inter-specific competitions and the evolutionary trajectory of populations. Recent technological advances have enabled large-scale molecular (e.g., RNAseq) and behavioral (e.g., computer vision) studies, but the study of anatomical responses to ecological conditions has lagged behind. Here, we highlight the role of X-ray micro-computed tomography (micro-CT) in generating in vivo and ex vivo 3D imaging of anatomical structures, which can enable insights into adaptive anatomical responses to ecological environments. To demonstrate the application of this method, we manipulated the larval density of Drosophila melanogaster Meigen flies and applied micro-CT to investigate the anatomical responses of the male reproductive organs to varying intraspecific competition levels during development. Our data is suggestive of two classes of anatomical responses which broadly agree with sexual selection theory: increasing larval density led to testes and ejaculatory duct to be overall larger (in volume), while the volume of accessory glands and, to a lesser extent, ejaculatory duct decreased. These two distinct classes of anatomical responses might reflect shared developmental regulation of the structures of the male reproductive system. Overall, we show that micro-CT can be an important tool to advance the study of anatomical (adaptive) responses to ecological environments.

The European Academy of Andrology (EAA) ultrasound study on healthy, fertile men: An overview on male genital tract ultrasound reference ranges.

BACKGROUND: So far, male genital tract color-Doppler ultrasound (MGT-CDUS) was not standardized. Recently, the European Academy of Andrology (EAA) published the results of a multicenter study assessing the CDUS characteristics of healthy-fertile men (HFM) to obtain normative parameters. OBJECTIVES: To report the EAA US study (i) standard operating procedures (SOPs) for assessing MGT-CDUS, (ii) main MGT-CDUS normative parameters, and (iii) compare the EAA and previously published "normal" CDUS values. METHODS: A cohort of 248 HFM (35.3 ± 5.9 years) was studied, evaluating MGT-CDUS before and after ejaculation following SOPs. RESULTS: SOPs for MGT-CDUS assessment are summarized here. All subjects underwent scrotal CDUS and 188 men underwent transrectal ultrasound before and after ejaculation. The main CDUS reference ranges and characteristics of the HFM-MGT are reported here. The mean testicular volume was ∼17 mL. The lower limit for right and left testis was 12 and 11 mL, defining testicular hypotrophy. The upper limit for epididymal head, body, tail, and vas deferens was 11.5, 5, 6, and 4.5 mm, respectively. Testicular and epididymal arterial reference ranges are reported. The EAA varicocoele classification is reported. CDUS-varicocoele was detected in ∼37% of men. Prostate mean volume was ∼25 mL, while lower and upper limits were 15 and 35 mL, defining hypotrophy and enlargement, respectively. Prostate arterial reference ranges are reported. Prostate calcifications and inhomogeneity were frequent; midline prostatic cysts were rare and small. Ejaculatory duct abnormalities were absent. The upper limit for periprostatic venous plexus was 4.5 mm. Lower and upper limits of seminal vesicles (SV) anterior-posterior diameter were 6 and 16 mm, defining hypotrophy or dilation, respectively. Seminal vesicle volume and ejection fraction reference ranges are reported. SV-US abnormalities were rare. Deferential ampullas upper limit was 6 mm. A discussion on the EAA and previously published "normal" CDUS values is reported here. CONCLUSIONS: The EAA findings will help in reproductive and general male health management.

No evidence for asymmetric sperm deposition in a species with asymmetric male genitalia.

Background: Asymmetric genitalia have repeatedly evolved in animals, yet the underlying causes for their evolution are mostly unknown. The fruit fly Drosophila pachea has asymmetric external genitalia and an asymmetric phallus with a right-sided phallotrema (opening for sperm release). The complex of female and male genitalia is asymmetrically twisted during copulation and males adopt a right-sided copulation posture on top of the female. We wished to investigate if asymmetric male genital morphology and a twisted gentitalia complex may be associated with differential allocation of sperm into female sperm storage organs. Methods: We examined the internal complex of female and male reproductive organs by micro-computed tomography and synchrotron X-ray tomography before, during and after copulation. In addition, we monitored sperm aggregation states and timing of sperm transfer during copulation by premature interruption of copulation at different time-points. Results: The asymmetric phallus is located at the most caudal end of the female abdomen during copulation. The female reproductive tract, in particular the oviduct, re-arranges during copulation. It is narrow in virgin females and forms a broad vesicle at 20 min after the start of copulation. Sperm transfer into female sperm storage organs (spermathecae) was only in a minority of examined copulation trials (13/64). Also, we found that sperm was mainly transferred early, at 2-4 min after the start of copulation. We did not detect a particular pattern of sperm allocation in the left or right spermathecae. Sperm adopted a granular or filamentous aggregation state in the female uterus and spermathecae, respectively. Discussion: No evidence for asymmetric sperm deposition was identified that could be associated with asymmetric genital morphology or twisted complexing of genitalia. Male genital asymmetry may potentially have evolved as a consequence of a complex internal alignment of reproductive organs during copulation in order to optimize low sperm transfer rates.