Contractility and electrophysiological parameters of cremaster muscles of boys with a hernia or undescended testis

Impact of seasonal variations on incidence and laterality of testicular torsion

Nowadays, there is confusing evidence in the literature regarding the association between seasonal variations and events of testicular torsion (TT). We attempted to assess the correlation between seasonal variations, including season, ambient temperatures, and humidity levels to onset and laterality of testicular torsion. We conducted a retrospective review of patients diagnosed with testicular torsion and confirmed surgically between January 2009 and December 2019, at Hillel Yaffe Medical Center. Weather data was collected from meteorological observation stations near the hospital. TT incidents were stratified into five temperature categories (< 15 °C, 15-20 °C, 20-25 °C, 25-30 °C, > 30 °C) and into two categories of humidity (≤ 50%, > 50%). Potential associations between TT and seasonal variations were investigated. Of 235 patients diagnosed with TT, 156 (66%) were children and adolescents and 79 (34%) were adults. In both groups, rate of TT incidents increased in winter and fall months. Significant correlation between TT and temperatures below 15 °C was observed in both groups; OR 3.3 [95% IC 1.54-7.07], p = 0.002 in children and adolescents and 3.77 [1.79-7.94], p < 0.001) in adults. The correlation between TT and humidity was non-significant in both groups. Among children and adolescents left-sided TT was observed in most of the cases, with strong correlation to lower temperatures; OR 3.15 [1.34-7.40], p = 0.008. Higher rates of acute TT were observed in patients admitted to the emergency department (ED) during the cold seasons in Israel. Significant association was observed between left-side TT and temperatures below 15 °C in the children and adolescents' group. Our findings suggest that there might be a predilection for TT occurrence in cold weather, particularly left-side laterality among children and adolescents.

Testicular torsion and climate changes in macroregions of São Paulo, Brazil

Objective:

To analyze the association between climate changes in the macroregions in the state of São Paulo and testicular torsion treated cases.

Methods:

The cases were selected in the Brazilian Public Health Data System Database from January 2008 to November 2016. All surgical procedure records were identified by the Hospital Admission Authorization document. Two codes were selected to process the search: testicular torsion (surgical cure code) and acute scrotum (exploratory scrototomy code). The macroregions were grouped in five areas linked to climate characteristics by International Köppen Climate Classification.

Results:

A total of 2,351 cases of testicular torsion were registered in the period. For the areas B, C and E (testicular torsion n=2,130) there were statistical differences found in association of testicular torsion cases and decreased temperature (p=0.019, p=0.001 and p=0.006, respectively), however, in analyses for the areas A and D statistical differences were not observed (p=0.066 and p=0.494).

Conclusion:

Decrease in temperature was associated with testicular torsion in three macroregions of São Paulo. The findings support the theory of cold weather like a trigger in occurrence of testicular torsion in a tropical climate region.

Testicular torsion and weather conditions: analysis of 21,289 cases in Brazil

PURPOSE

The hypothesis of association between testicular torsion and hyperactive cremasteric reflex, worsened by cold weather, has not been proved. Thirteen studies in the literature evaluated this issue, with inconclusive results. The aim of the present study was to evaluate the seasonality of testicular torsion in a large subset of patients surgically treated in Brazil, and additionally to estimate the incidence of testicular torsion.

MATERIALS AND METHODS

Brazilian Public Health System Database was assessed from 1992-2010 to evaluate hospital admissions associated with treatment of testicular torsion. Average monthly temperature between 1992-2010 was calculated for each region.

RESULTS

We identified 21,289 hospital admissions for treatment of testicular torsion. There was a higher number of testicular torsions during colder months (p = 0.002). To estimate the incidence of testicular torsion, we have related our findings to data from the last Brazilian census (2010). In 2010, testicular torsion occurred in 1.4:100,000 men in Brazil.

CONCLUSIONS

Testicular torsion occurred at an annual incidence of approximately 1.4:100,000 men in Brazil in 2010. Seasonal variations do occur, with a significant increase of events during winter. Our findings support the theory of etiological role of cold weather to the occurrence of testicular torsion. Strategies to prevent these events can be based on these findings.

Diurnal temperature change is associated with testicular torsion: a nationwide, population based study in Taiwan

PURPOSE

We investigated the association between climatic variables and testicular torsion in Taiwanese males.

MATERIALS AND METHODS

Using the Taiwan Longitudinal Health Insurance Database, we reviewed the files of patients who were diagnosed with testicular torsion and underwent orchiectomy or orchiopexy between January 1996 and December 2008. Children younger than 1 year were excluded from the study. Climatic data were provided by the Taiwan Central Weather Bureau and included ambient temperature, relative humidity, diurnal temperature change and barometric pressure. Patients with acute appendicitis who underwent appendectomy were chosen as the control group. Climatic variables in relation to testicular torsion were analyzed using the Mann-Whitney U test and chi-square test, and seasonal climatic variations using the Kruskal-Wallis H test. Relative risk was calculated to compare the incidence of testicular torsion for diurnal temperature changes.

RESULTS

A total of 65 patients with a mean age of 16.2 years presented with testicular torsion and were treated surgically. Four children younger than 1 year were excluded, and thus the study population consisted of 61 patients. The estimated incidence of testicular torsion was 2.58 per 100,000 person-years. There were no special climatic conditions on days of admission. However, 73.7% of the patients had testicular torsion when the diurnal temperature change was 6C or greater. Compared to the torsion rate for diurnal temperature changes less than 6C, the relative risk of testicular torsion at 6C or greater was 1.8 (p = 0.05). Average seasonal diurnal temperature change in the 2 days before hospitalization showed increases in all seasons except spring, which fluctuated.

CONCLUSIONS

Diurnal temperature change was associated with testicular torsion and may be an etiological climatic factor affecting this condition. This is the first known study to demonstrate an association between diurnal temperature change and testicular torsion.

Seasonality of testicular torsion: a 10-year nationwide population based study

PURPOSE

Using a 10-year nationwide data set, we examined seasonal variability in the monthly incidence of testicular torsion in Taiwan. We also investigated the association between meteorological factors (ambient temperature, relative humidity, atmospheric pressure, rainfall and total hours of sunshine) and testicular torsion, stratified by age group.

MATERIALS AND METHODS

This study retrieved data from the National Health Insurance Research Database. We identified 1,782 hospitalizations for testicular torsion between 2000 and 2009. Spearman's rank correlation was used to explore possible associations between climatic parameters and the monthly incidence of testicular torsion. In addition, we used the ARIMA method (Auto-Regressive Integrated Moving Average) to test for seasonality in the incidence of testicular torsion.

RESULTS

The results demonstrated a fairly similar seasonal pattern in monthly incidence rates for testicular torsion across both age groups and the combined groups. January (midwinter) had the highest rates, which decreased in April to a trough in June (early summer). After adjusting for the time trend effect and climatic parameters, the ARIMA regression revealed that January had a significantly higher monthly incidence of testicular torsion compared to February. In addition, our results indicated that the monthly incidence of testicular torsion was negatively associated with ambient temperature.

CONCLUSIONS

Our results suggest that the monthly incidence of testicular torsion was significantly associated with seasonality and ambient temperature.

The role of cremaster muscle in testicular descent in humans and animal models

Testicular descent is a complex developmental process involving anatomical and hormonal regulation. The gubernaculum undergoes a "swelling reaction" during the transabdominal phase and is mainly under the control of Insulin-Like Peptide 3 (INSL-3) and Mullerian Inhibitory Substance/Anti-Mullerian Hormone (MIS/AMH). The second phase of testicular descent is regulated by androgens and calcitonin gene-related peptide (CGRP) release from the sensory nucleus of the genitofemoral nerve (GFN). In rodents, the active proliferation of the gubernacular tip and cremaster muscle, its rhythmic contraction, as well as the chemotactic gradient provided by the CGRP result in eventual migration of the testis into the scrotum. This review illustrates the structural aspects and hormonal control of cremaster muscle development to better understand the mechanism of testicular descent in normal rodents and humans, compared to diseased rodent models. The analysis showed the cremaster muscle is formed from mesenchymal differentiation of the gubernacular tip and is not a direct passive extension of internal oblique muscle. Cremaster muscle matures slower than other body muscles, and the persistence of immature myogenic proteins seen in cardiac muscle allows rhythmic contraction to guide the testis into the scrotum. Finally, remodelling of the cremaster muscle enables gubernacular eversion. Further understanding of the molecular regulators governing the structural and hormonal changes in the cremaster muscle may lead to new advances in the treatment of undescended testes.

Effect of high environmental temperature on semen parameters among fertile men

OBJECTIVE

To evaluate the effect of high environmental occupational temperature on semen parameters of fertile men.

DESIGN

Prospective.

SETTING

Steel-casting plant.

PATIENT(S)

Ninety fertile workers exposed to a high temperature compared with 40 fertile workers working under ordinary conditions as control subjects.

INTERVENTION(S)

Measurement of scrotal temperature by invagination thermometry, air temperature, relative humidity by aspirated psychrometer, radiant heat by globe thermometer, air velocity by light vane anemometer, and semen analysis.

MAIN OUTCOME MEASURE(S)

Scrotal temperature and semen analysis.

RESULT(S)

Nonsignificant difference was found between the two groups regarding their scrotal temperature. Also, nonsignificant differences were demonstrated regarding semen analysis parameters being in the normozoospermic range.

CONCLUSION(S)

Under high environmental temperature, semen parameters were within normozoospermic levels owing to body acclimatization mechanisms.

Sarco(endo)plasmic reticulum and plasmalemmal Ca(2+)-ATPase activities in cremaster muscles and sacs differ according to the associated inguinal pathology

Sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA) and plasmalemmal Ca(2+)-ATPase (PMCA) activities in cremaster muscles and sacs, which have been subjected to different autonomic tonuses, were determined and compared. Samples of cremaster muscles and sacs associated with male or female inguinal hernia, hydrocele or undescended testis were obtained from children during operations and activities of SERCA and PMCA were determined. While highest SERCA and PMCA activities were encountered among cremaster muscles and sacs associated with undescended testis, least activities were encountered among structures associated with hydrocele. The alterations in SERCA and PMCA activities in cremaster muscles associated with undescended testis appear to reflect the attempts at maintaining the levels of cytosolic calcium. Despite similar total calcium contents, lower SERCA and PMCA activities were found in sacs associated with hydrocele compared to those associated with undescended testis suggest a difference among the levels of cytosolic calcium.

Climatic conditions and the risk of testicular torsion in adolescent males

PURPOSE

The risk factors for acute testicular torsion are poorly understood. Environmental factors have been implicated by some authors and discredited by others. The only previous known study in the United States did not demonstrate any seasonal correlation, although the study was done in a warmer climate. We sought to determine if environmental factors impact the incidence of testicular torsion in our temperate climate conditions with a large differential between the warmest and coldest temperatures.

MATERIALS AND METHODS

We retrospectively studied patients who were diagnosed with testicular torsion between January 1997 and December 2006. Data regarding weather conditions were collected, including season, temperature, humidity and atmospheric pressure at the time of onset of symptoms. Spearman's rank correlation was performed to assess the relationship between atmospheric temperature and frequency of testicular torsion. Multivariate analysis was performed to analyze the effect of covariables.

RESULTS

A total of 58 children presented with testicular torsion. Mean temperature at onset of symptoms was 6.9C (range -12C to 23C). Of the patients 81% had symptom onset when the atmospheric temperature was less than 15C. Seasonal incidence of testicular torsion was 36.2%, 31%, 19% and 13.8% for spring, winter, summer and fall, respectively. Spearman's rank correlation test revealed a significant negative correlation between the incidence of testicular torsion and increasing temperature (r = -0.94, p <0.0001) and decreasing humidity (r = -0.44, p <0.001). After controlling for effects by patient age, atmospheric pressure and humidity by multivariate analysis a significant correlation was observed between testicular torsion and decreasing atmospheric temperature. None of the other atmospheric factors examined correlated with the incidence of testicular torsion.

CONCLUSIONS

An increased incidence of testicular torsion is seen with decreasing atmospheric temperature and humidity, suggesting a possible etiological role.

Contractility of rat gubernacula affected by calcitonin gene-related peptide and beta-agonist

PURPOSE

The effects of calcitonin gene-related peptide (CGRP), isoprenaline, and guanethidine on the neonatal rat gubernaculum were investigated in organ culture with the aim of seeing whether beta -agonists or beta -antagonists are involved in gubernacular development during testicular descent.

METHODS

A total of 200 gubernacula were studied. The gubernacula (n = 20 for each experiment) from male rat pups were incubated in aerated culture medium with isoprenaline (1 and 10 micromol/L) with/without CGRP (714 nmol/L) or guanethidine (1 and 10 micromol/L) with/without CGRP (714 nmol/L). Cultures were observed for 5 days by video camera to see spontaneous rhythmic contractions, which are known to correlate with normal gubernacular migration in the rodent.

RESULTS

Of gubernacula cultured without CGRP, 60% showed contractions by day 5, and the groups of isoprenaline and 10 micromol/L guanethidine showed similar rates, but only 15% of the 1 micromol/L guanethidine group showed contractility (P < .005). In contrast, of the gubernacula cultured with CGRP, each group showed high contractility from day 2 of the culture, and there was no difference between each group and the CGRP-alone group.

CONCLUSIONS

Although the beta -blocker showed a weak inhibitory effect on de novo gubernacular contractility, CGRP had a stronger effect on contractility, overriding any possible effects of the beta -neuron pathway. The contractility of the rat gubernaculum during testicular descent is primarily mediated by the genitofemoral sensory nerve fibers via release of CGRP, but beta -adrenergic nerves also may be involved.

A comparative histopathological evaluation of sacs from boys and girls with inguinal hernia

The purpose of this study is to determine and to compare histopathologic alterations of hernia sacs obtained from patients with inguinal hernia with those of the peritoneal tissue from patients operated on for other abdominal disorders. Samples were obtained from 42 pediatric patients with uni- or bilateral hernias, and from 30 pediatric control patients without hernia. Sections were stained with hematoxylin-eosin, Gomori's trichrome, and Gomori's reticulin. Furthermore, they were immunohistochemically stained with anti-synaptophysin for the quantification of neural structures. All the slides were examined for six parameters, including variations in tissue and collagen types, the presence of inflammation and proliferation of vessels, neural plexus, and mesothelial cells. The results were evaluated statistically using the independent T-test and the Mann-Whitney-U test. Parametric tests revealed a higher presence of large neural plexus (p = 0.003), increased proliferation of mesothelial cells (p = 0.009), and hypervascularization (p = 0.003) in sacs of the hernia group. There were also major changes that were dependent on the sex of the patients. Most part of hernia sacs tissue was found to be fibrous and adipose in most boy patients, but was fibro-muscular in girls with inguinal hernia (male/female p = 0.03), while the tissues were fibro-adipose in both sexes in the control group (inguinal hernia/control p = 0.016). Similarly, vascular proliferation was mainly encountered in hernia sacs of girls (p = 0.013). These features were not observed in the control groups. Therefore, on the basis of sex, we determined whether or not these findings could indicate the difference between the etiopathologic mechanisms of inguinal hernias. Furthermore, we went into the question of whether or not the comprehensive examination of hernia sacs sufficed to enlighten the etiology of hernias.

Chemical sympathectomy by 6-OH dopamine during fetal life results in inguinal testis through altering cremasteric contractility in rats

BACKGROUND/PURPOSE

Androgens are proposed to influence testicular descent through modulating sympathetic tone. An experimental study was undertaken to evaluate the effects of prenatal chemical sympathectomy on testicular location associated with the alterations in contractile properties of cremaster muscles in rats.

METHODS

Time-mated pregnancies were started in 10 rats. Two groups, each receiving saline or 6-hydroxydopamine from day 15 to day 19 of intrauterine life were established. At 2 months of age, localization of testes were evaluated, cremaster muscles were removed, and contractile properties were studied. Twitch and tetanic contractions were recorded isometrically at 37 degrees C. Effects of verapamil, isoprenaline, and L-NNA were investigated. Results were compared through analysis of variance (ANOVA), and P values less than.05 were considered to be significant.

RESULTS

Both testes of all male offspring in the control group (n = 19) were in the scrotum. Six offspring among 17 subjected to 6-hydroxydopamine had undescended testes. Treatment with 6-hydroxydopamine had no effect on force-frequency relationship of cremaster muscle strips. Cremaster muscles of rats exposed to 6-hydroxydopamine had lower sensitivity to voltage-sensitive Ca++ channel blockade by verapamil (3 x 10(4) mol/L; P <.05). These muscles displayed greater contractile response to isoprenaline (10(-5) mol/L; P <.05) but not to nitric oxide synthase inhibition by N(omega)-nitro-L-arginine. Alterations in contractile properties of the muscles did not differ according to localization of testes among rats subjected to 6-hydroxydopamine.

CONCLUSIONS

Administration of 6-hydroxydopamine resulted in suprascrotally located testes. This localization has been associated with less exposure at sympathetic tonus. These findings support that sympathetic activity plays an important role in localization of testis.

Mechanisms involved in contractile differences among cremaster muscles according to localization of testis

BACKGROUND/PURPOSE

Evidence suggests differences in contractility in cremaster muscles (CM) associated with undescended testis caused by alterations of autonomic innervation. Contractile responses of CM to various pharmacologic agents were evaluated and compared according to the localization of testis.

METHODS

Samples of CM from boys with undescended testis or inguinal hernia were obtained. Twitch and tetanic contractions were recorded isometrically at 37 degrees C. Effects of verapamil, isoprenaline, calcitonin gene-related peptide (CGRP), substance P (SP) and N(omega)-nitro-L-arginine (L-NNA) were investigated. Results were compared through 2-way analysis of variance, and P values less than.05 were considered to be different.

RESULTS

Verapamil alone significantly (P <.05) decreased contraction amplitudes in CM from both sources; the decrease was more pronounced in CM from boys with inguinal hernia (P <.05). Although isoprenaline increased contraction amplitudes in CM associated with undescended testis (P <.05), CGRP and SP increased contraction amplitudes in CM associated with descended testis (P <.05). L-NNA increased contraction amplitudes in both groups (P <.05). The decrease of contraction amplitudes after verapamil displayed a similar pattern after isoprenaline, SP, and L-NNA. Verapamil-induced contractility decrease was more pronounced after CGRP in both groups (P <.05).

CONCLUSIONS

Sensitivity of CM to verapamil differs according to localization of testis. Isoprenaline enhances contractility by stimulating Na(+)-K(+)ATPase in undescended testis without altering voltage-sensitive channel sensitivity to verapamil. CGRP and SP increase contractility in inguinal hernia, and CGRP increases the sensitivity of voltage-sensitive Ca(2+) channels to verapamil in CM from both groups. Nitric Oxide (NO) exerts inhibitory action on CM contractility, and it is less pronounced in undescended testis. These differences may contribute to pathophysiology of undescended testis.

Cremasteric reflex and retraction of a testis

PURPOSE

A clinical study has been planned to define the clinical characteristics of cremasteric reflex (CR) for deciding on the possibility of a prolonged suprascrotal stay of a testis through this reflex.

METHODS

Five hundred boys from 3 days to 16 years of age were divided into 6 groups according to their ages and were evaluated for the presence of the CR. After evoking CR, the presence or absence of changes in testicular location and the most elevated position of the testis were recorded. Testicular position difference (TPD), the duration of the stay of testis in the most elevated position (DEP), and the interval for reevoking the CR (IRCR) were determined. The number of consecutive responses after repetitive evokings were recorded as reproducibility (R). Mean TPD, DEP, IRCR, and R values for both sides were calculated and compared among groups. The boys with a positive reflex were classified further according to their TPD, DEP, IRCR, and R values. Three groups were established according to the aforementioned criteria by dividing the values into 3 equal parts. The association of each of the parameters to other parameters were compared.

RESULTS

Bilateral positive CR was encountered in 42.7% of newborns, 36.3% of the boys between 1 month and 1 year old, 38.1% of the boys between 2 years and 4 years old, 75.2% of the boys between 5 years and 8 years old, 70.3% of the boys between 9 years and 12 years old, and 72.1% of the boys between 13 and 16 years old. The highest percentage of the contralateral activations during ipsilateral evokings were encountered in boys who were between 5 and 8 years of age. The highest mean TPD and mean R, the longest mean DEP, and mean IRCR were encountered in boys between 5 and 8 years of age. Boys with the highest TPD did not have shortest IRCR and highest R values. Similarly, boys with the longest DEP or shortest IRCR and highest R values did not have the association of other parameters that would suggest a hypersensitivity.

CONCLUSIONS

The rate of presence and the characteristics of a positive CR vary largely. However, suprascrotal location of a testis for extended periods through the activation of this reflex does not seem to be likely. Instead of a hyperactive reflex, the clinical condition, so called the retractile testis, might have resulted through alterations within the cremaster muscle itself. J Pediatr Surg 36:863-867.

Cremaster muscle is not sexually dimorphic, but that from boys with undescended testis reflects alterations related to autonomic innervation

BACKGROUND/PURPOSE

The genitofemoral nerve and its motor neuron are known to be sexually dimorphic. An association has been suggested to exist between antiandrogen-induced undescended testis and the genitofemoral nerve. Therefore, the cremaster muscles (CM) from boys and girls with inguinal hernia and boys with undescended testis were compared to evaluate the failed descent through sexual dimorphism.

METHODS

Samples of CM were obtained from 10 boys and 10 girls with inguinal hernia and 10 boys with undescended testis. Sections were stained for ATPase reactions after acid and alkaline preincubations, and for the expression of myosine heavy chains. The percentages of type 1 and type 2 fibers, and mean diameters of fibers according to the types were determined for each group. Values were compared through Mann-Whitney U test, and P values less than .05 were considered to be significant.

RESULTS

CM have mainly been composed of type 1 fibers. Distributions of type 1 and 2 fibers have not shown a difference among groups. Mean diameters of both type 1 and type 2 fibers from girls (P < .05), and mean diameter of type 2 fibers from boys with undescended testis have been significantly smaller than those encountered in boys with inguinal hernia (P < .05).

CONCLUSIONS

Although the mean diameter of type 1 fibers from boys with undescended testis has been as large as those encountered in boys with inguinal hernia, mean diameter of type 2 fibers has been as small as those encountered in girls. Among various reasons to selectively diminish the size of type 2 fibers, lack of beta adrenergic effect appears to be the most satisfactory explanation. J Pediatr Surg 36:877-880.

Ultrastructural deficiency in autonomic innervation in cremasteric muscle of boys with undescended testis

BACKGROUND/PURPOSE

The cremaster muscles (CM) associated with undescended testis reveal neurogenic alterations that mainly affect type 2 fibers. The ultrastructure of CM has been evaluated to define if further evidence to explain the alterations could be identified.

METHODS

CM of 8 boys with inguinal hernia and 8 boys with undescended testis at similar ages were biopsied. Samples were processed for electron microscopic evaluations. Semithin and thin sections were examined under an electron microscope.

RESULTS

The CM associated with inguinal hernia showed normal ultrastructure. However, some alterations were encountered in CM associated with undescended testis. Unmyelinated fibers were diminished in number, and myelinated fibers were outnumbering the unmyelinated fibers. Marked disorientation of myofibers, redundant sarcolemma, empty sleeves of basal lamina, disarray of myofibrils, densely packed myofilaments, Z disk streaming, dilated sarcoplasmic reticulum, and dense-irregularly shaped mitochondria were repeatedly encountered. Satellite cells appeared inactive. Most of the fibers were contracted.

CONCLUSIONS

The decrease in number of unmyelinated fibers appears to represent a decrease in autonomic nerve fibers. The alterations within muscle fibers may reflect a deficiency in autonomic innervation. Autonomic nervous system is highly responsive to circulating androgens. Factors decreasing the vulnerability of autonomic nervous system against androgenic effects may result in a CM with neurogenic alterations, thus inhibiting testicular descent. J Pediatr Surg 36:573-578.

Distribution and morphometry of fiber types in cremaster muscles of boys with inguinal hernia or undescended testis

In the present study, we determined and compared the distribution and mean diameters of fiber in the cremaster muscles (CM) of boys with either inguinal hernia (IH) or undescended testis (UT). Samples of CM were obtained from 20 patients (10 boys with IH, and 10 boys with UT) of similar age. The CM muscles of two boys each, without inguinal pathology, were sampled during autopsy. Sections were stained for oxidative and glycolytic enzymes, as well as for ATP-ase reactions after acid (pH: 4.6) and alkaline (pH: 10.6) preincubations. Specimens were also analyzed morphometrically using a KONTRON 400 computerized image analysis system. The Mann- Whitney U test was applied to compare the percentages of fiber types and mean diameters of fibers according to the types of the CM of boys with IH or UT. In boys, the CM is mainly composed of type 1 fibers. The CMs of patients with UT reveal alterations of neurogenic origin. Although both type 1 and type 2 fibers reveal alterations, type 2 fibers appear to be affected more profoundly and characterized by significantly decreased mean diameters. Significantly decreased mean diameters of type 2 fibers in CM may support disuse, lack of sensitivity to the hormonal influences, or an alteration in the corticospinal tracts of boys with UT.

Cremaster muscles obtained from boys with an undescended testis show significant neurological changes

OBJECTIVE

To compare cremaster muscles (CMs) obtained from boys with inguinal hernia, hydrocele or an undescended testis and those obtained from girls with inguinal hernia, thus defining the changes associated with each clinical condition.

MATERIALS AND METHODS

CM samples were obtained from 26 boys and three girls with inguinal hernia, and 18 boys who had undergone surgery for an undescended testis (12) or hydrocele (six). The samples were frozen in isopentane cooled in liquid nitrogen and were processed for sectioning by cryostat. Sections (12 microm) were stained with a several histochemical stains. The presence of central nuclei, fibre splitting, basophilic fibres, fibre necrosis, inflammatory changes, small angular fibres, fibre hypertrophy, grouped atrophy, and endo- and perimysial fibrosis were evaluated. From each specimen, 200 fibres were also analysed morphometrically using a computerized image analysis system.

RESULTS

Neurogenic changes were apparent in all the CMs from patients with an undescended testis but none of the samples obtained from girls showed any changes. While only two specimens of 26 from boys with inguinal hernia (8%) had evidence of neurological alterations, eight CM (31%) had general changes. The mean (SD) fibre diameters did not differ significantly among the groups with inguinal hernia, hydrocele and undescended testis, at 23. 0 (8.6), 24.4 (4.5) and 23.0 (10.5) microm, respectively.

CONCLUSION

Cremasteric muscles associated with an inguinal hernia or an undescended testis differ; neurogenic changes were detected within all the CM of boys with an undescended testis. These changes in the CM may have influenced the location of the testis.

Lack of carbachol response indicates the absence of cholinergic receptors in sacs associated with undescended testis

BACKGROUND/PURPOSE

The mechanism of testicular descent remains controversial. The processus vaginalis (PV) contains smooth muscle and should have contractile activity that may contribute to descent. This study was designed to evaluate the smooth muscle of PVs associated with incomplete obliteration for spontaneous activities and responses to various stimuli, to determine if differences exist according to sex, diagnostic source, or location of the testis.

MATERIALS

Peritoneal samples (n = 4); sacs from girls (n = 8) and boys with inguinal hernia (n = 12); and sacs from boys with hydrocele (n = 3), hydrocele of the cord (n = 2), or undescended testis (n = 7) were used for the current study. Tissues were attached to the isometric force displacement transducer in an organ bath containing mammalian Ringer's solution at 37 degrees C. Spontaneous mechanical activity and contractile responses of tissues to the electrical field stimulation, phenylephrine, carbachol, and serotonin were recorded. The values obtained from boys and girls with inguinal hernia and from boys with either undescended or descended testis were compared through Fisher's Exact test.

RESULTS

There were no statistically significant differences in patient age between groups. Among the parameters studied, only the carbachol response of the sacs associated with undescended testis showed a significant difference compared with the others (P = .001). None of the sacs associated with undescended testis responded to carbachol, whereas all of the sacs from boys and girls with inguinal hernia responded to carbachol.

CONCLUSIONS

Lack of carbachol response suggests the absence of cholinergic receptors within the sacs associated with undescended testis. The lack of cholinergic receptors may play a role in the failure of the process of testicular descent by hindering either PV elongation into the scrotum or a possible propulsive activity of the PV on the testis.

Cremasteric reflexes of boys with descended, retractile, or undescended testes: an electrophysiological evaluation

BACKGROUND/PURPOSE

Retractile testis traditionally has been regarded as suprascrotal location of testis resulting from hyperactivity of the cremasteric reflex (CR). However, the activity of CR is evaluated poorly in the literature. Electrophysiological characteristics of CR in boys with various testicular localizations have been evaluated comparatively.

METHODS

Cremasteric responses that were evoked by electrical stimulation of the upper-inner aspect of thigh were recorded using a concentric needle electromyography (EMG) electrode inserted into the cremaster muscle. Evoked EMGs of groups, each consisting of 10 boys with bilateral descended (DT), unilateral retractile (RT), or unilateral undescended testes (UT) were compared for response latencies and durations.

RESULTS

Three components with different onset latencies (R1, R2, and R3) were identified in EMG responses. In patients with UT, the latency of the R1 was shorter than that of the patients with DT, and the duration of R2 was longer than those of the patients with DT and RT. The differences between patients with RT and DT regarding the latency and duration of R1 and R2, although similar to those differences between UT and DT, were not significant. There were no significant differences of the latencies of R3 between groups. In patients with RT and UT, response latency and duration in the descended and retractile-undescended sides were similar.

CONCLUSIONS

Defined by shortened latency and prolonged activity of cremasteric responses, which probably reflect a diminished neuronal inhibitory control, CR is hyperactive in UT. Disinhibited motor neurons leading to overactivity of cremaster muscle might have hampered the descent of testis. Our results do not provide a definite support for or against the hypothesis of CR hyperactivity in RT.