Tetsuji Maruyama

Accuracy of ultrasonography and magnetic resonance imaging in the diagnosis of non-palpable testis

Background: Studies were needed to evaluate the accuracy of ultrasonography (US) and magnetic resonance imaging (MRI) for diagnosing non‐palpable testis, and to study the clinical usefulness of US and MRI before surgical exploration.

Comparison between ultrasonography and retrograde urethrography for detection of prostatic utricle associated with hypospadias

OBJECTIVES To evaluate the practical application and limitation of ultrasonography and retrograde urethrography in detecting prostatic utricle associated with hypospadias. METHODS Between 1995 and 1999, 80 patients with hypospadias, 1 month to 16 years of age (mean age 3 years, 6 months), underwent ultrasonography and retrograde urethrography to detect the prostatic utricle. RESULTS Of the 80 patients examined, the prostatic utricle was found in a total of 36 patients (45.0%) by ultrasonography and/or retrograde urethrography. Ultrasonography revealed the prostatic utricle in 27 (75%) of the 36 patients; in 6 of the 27, it was not detected by retrograde urethrography. Retrograde urethrography revealed the prostatic utricle in 30 (83%) of the 36 patients; in 9 of the 30, it was not visualized by ultrasonography. Retrograde urethrography was slightly more sensitive in detecting the prostatic utricle than was ultrasonography. In the remaining 44 patients, the prostatic utricle was not detected by either examination method. CONCLUSIONS Although retrograde urethrography is considered the most useful method for detecting any degree of the prostatic utricle, we recommend routine ultrasonography because it is noninvasive, painless, and simple.

Primary and salvage urethroplasty using Mathieu meatal-based flip-flap technique for distal hypospadias

Abstract Background: Numerous surgical procedures have been attempted for correction of distal hypospadias. The Mathieu procedure was employed in this study for secondary cases as well as primary cases.

Identification of Differentially Expressed Genes in Human Cryptorchid Testes Using Suppression Subtractive Hybridization

PURPOSE To restore fertility the current consensus suggests early orchiopexy for cryptorchidism. However, despite early orchiopexy it is reported that transformation of gonocytes into adult dark spermatogonia is already impaired at the time of surgery and consequently affects future fertility. To elucidate the biological processes occurring during germ cell maturation in the cryptorchid testis, we identified the genes affected by testicular maldescent using polymerase chain reaction based suppression subtractive hybridization, and investigated differentially expressed genes to determine whether they are related to cell differentiation and spermatogenesis. MATERIALS AND METHODS Testicular tissues were excised from 24 boys 12 to 59 months old who underwent orchiopexy or hydrocelectomy at our hospital. Two-way subtraction was performed to compare their tissue samples and those from age matched boys with ipsilateral cryptorchidism and a descended testis. Differential expression was validated by real-time reverse transcriptase polymerase chain reaction. To clarify the distribution of candidate genes, immunohistochemical and western blot analysis was performed. RESULTS We obtained 84 clones corresponding to transcripts representing differential expression. Basic local alignment search tool searches revealed 32 different known genes with 98% to 100% similarity. Among these genes we further investigated 3 genes, TPT1, EEF1A1 and NuMA1, which were significantly more highly expressed in cryptorchidism than in descended testes and were detected in the spermatogonia from immature to adult testes. CONCLUSIONS TPT1, EEF1A1 and NuMA1 have cell growth related functions, suggesting that they have certain roles in germ cell differentiation and maintenance of stem cell potential. Changes in the expression levels of these genes in the testes might enable novel evaluation of spermatogenic failure caused by cryptorchidism.

Detection of the Sex-Determining Region of the Y Chromosome in 46,XX True Hermaphroditism

Objectives: Two cases of 46,XX true hermaphroditism were analyzed for two Y-DNA sequences, including the recently cloned gene for male testis determination, the sex-determining region of the Y chromosome (SRY). Methods: Polymerase chain reaction was performed to amplify the SRY. DNA was prepared from peripheral blood lymphocytes as well as from gonadal tissue preserved in a paraffin block. Results: One hermaphrodite contained the SRY sequences in peripheral blood lymphocytes and the testicular part of ovotestis tissue preserved in a paraffin block, while in the second patient these sequences were not detected. Conclusions: The SRY positive subject resulted from occult Y mosaicism rather than from X–Y translocation. Testis differentiation in the SRY negative subject may have been caused by mutation of a gene on the X chromosome or, alternatively, on an autosome.

Neo-modified Koyanagi technique for the single-stage repair of proximal hypospadias

PURPOSE To retrospectively analyze the results of a modification of the Koyanagi hypospadias repair developed to reduce complications. MATERIALS AND METHODS Twelve boys underwent a modified Koyanagi repair over the past 3 years. The technique included the preservation of a wide vascular pedicle for each parameatal flap. The distal urethral plate was left intact and attached on each lateral side to the medial side of each distal Koyanagi pedicle flap. RESULTS One boy (8%) developed a urethral fistula. There was no instance of meatal stenosis, sacculation or urethral stricture. CONCLUSIONS Modifying the Koyanagi repair by preserving a wide vascular pedicle for the distal skin flaps and utilizing the distal urethral plate as the base for the distal neourethra has lowered the incidence of complications. This technique is a suitable alternative to a two-stage approach for the correction of proximal hypospadias.

Correction of completely buried penis using the modified preputial island pedicle flap method

The buried penis is a rare congenital abnormality caused by a deficiency of penile shaft skin and abnormal attachments of the dartos fascia to Bucks fascia. The basis for surgical correction is directed at freeing the penile shaft from abnormal dartos attachments, refixing dartos fascia to Bucks fascia to prevent retraction of the penis, and providing adequate shaft skin coverage with the inner preputial skin. The authors report a modified preputial island pedicle flap method for correcting the completely buried penis performed on 2 patients (ages 9 months and 1 year) at Nagoya City University Medical School.

Pseudo-clitoromegaly associated with congenital prepubic sinus

Abstract  We operated on a 12‐year‐old girl who had clitoromegaly and a sinus on the midline prepubic area congenitally. The prepubic sinus appeared to point to the clitoris on the preoperative magnetic resonance image, but the relation between the sinus and clitoromegaly was unclear. Gray‐brown discharge was emitted at the site of dissection between the prepuce and clitoris and the size of the clitoris became normal. The sinus was excised, revealing a tract 1.5 cm long that extended to the retropubic sinus, and ended in a fibrous tract that was linked to the clitoris. This suggested pseudo‐hypertrophy because of the discharge collected in the end of the prepubic sinus.

A Japanese View on Circumcision: Nonoperative Management of Normal and Abnormal Prepuce

Circumcision is generally undertaken for 3 reasons; first, as an item of religious practice, typically neonatally, although occasionally transpubertally, as a rite of passage; second, as a prophylactic measure against future ailments (for the reduction in the risk of penile cancer, urinary tract infection, and sexually transmitted disease); and third, for immediate medical indication. There are many different views worldwide on circumcision; we are presenting a Japanese view on the management of pediatric foreskin.

Management of urethral calculi associated with hairballs after urethroplasty for severe hypospadias

Abstract:  Urethral calculus is a late complication of urethroplasty for hypospadias when hair‐bearing scrotal skin is included in the neourethra. From 1992 to 2002, we had one adolescent and four adult hypospadiac patients with urethral calculi. All patients had undergone staged repair for severe hypospadias at our institute or another hospital in their childhood. Open ureterolithotomy or endoscopic ureterolithotripsy was conducted except in one patient. Open ureterolithotomy was conducted successfully including retubularization with trimming of the diverticular area of the neourethra in two patients. Endoscopic ureterolithotripsy was conducted via Lithoclast in the other two patients. The calculi were struvite in the four patients.