Biomedical subjects

Akihide Hirayama

Publications and source records attributed to Akihide Hirayama.

14 recordsLinked to original sources

PubMed2006

Decrease in nocturnal urinary levels of arginine vasopressin in patients with nocturnal polyuria.

OBJECTIVES: To elucidate whether heart function and endocrine levels of arginine vasopressin (AVP) or solute diuresis is associated with the nocturnal voided volume, and whether the urinary AVP could be a parameter for screening for nocturnal polyuria caused by AVP insufficiency. METHODS: A total of 50 patients were enrolled in this study. The blood and urine samples were obtained every 6 hours at 6 pm, 12 am, 6 am, and 12 pm. Atrial natriuretic peptide and brain natriuretic peptide were measured at admission. All voided urine samples were collected every 6 hours for examination. The evaluation items were AVP, osmolarity, sodium, potassium, chloride, and creatinine in blood and urine. RESULTS: The patients were classified into a group with nocturnal polyuria (n = 21) and a group without nocturnal polyuria (n = 25). There was no significant difference in atrial natriuretic peptide, brain natriuretic peptide, electrolytes in blood and urine, and plasma AVP of each sample between the two groups, but urinary AVP/urinary creatinine and urine osmolarity at 12 am and 6 am in the group with nocturnal polyuria were significantly lower than those in the group without nocturnal polyuria. The nocturnal voided volume correlated with urinary AVP/urinary creatinine level in the urine samples obtained at 12 am and 6 am. CONCLUSIONS: The present data have demonstrated that the significant decrease in urinary AVP/urinary creatinine level at 6 am may contribute to the increased nocturnal voided volume followed by nocturia and that the circadian rhythm disorder of AVP can be predicted by a noninvasive test measuring urinary AVP/urinary creatinine in the urine voided early in the morning.

Aged↗

PubMed2006

Sexuality and seeking medical help for erectile dysfunction in young adults with spina bifida.

OBJECTIVES: The objectives of this study were to evaluate the correlation between the sexual function of spina bifida (SB) patients and Sharrard classification, touch sensation on the penis, to examine if SB patients who are sexually active have erectile dysfunction (ED) on the International Index of Erectile Function-5 (IIEF5), and to clarify if they seek medical treatment for ED. METHODS: Thirty-six male SB patients aged over 18 years were enrolled. A questionnaire was sent to all patients that included the following items: touch sensation on the penis, psychogenic erection, rigidity at erection, ejaculation, orgasm and experience in sexual intercourse. In addition, patients who had experience in sexual intercourse were asked about ED through the use of the IIEF5 and whether or not they sought medical help for their ED. RESULTS: Twenty-six patients responded. The positive rates of psychogenic erection, rigidity at erection, ejaculation and orgasm were 85%, 54%, 88% and 65% respectively. Psychogenic erection and ejaculation correlated with Sharrard classification. Rigidity at erection and orgasm correlated with touch sensation on the penis. Eleven patients had experience in sexual intercourse and six of them were diagnosed as having ED on the IIEF5. There were no factors correlating with ED. None of the patients sought medical advice and none was treated for ED. CONCLUSIONS: Sexual function of SB patients could be predicted by Sharrard classification and touch sensation on the penis to some degree. However, ED did not correlate with sexual function. Therefore, we should not evaluate the neurological loss but instead provide adequate information.

Adolescent↗

PubMed2006

[Operative position suitable for transvaginal excision of urethral diverticulum or closure of urethrovaginal fistula].

Among the various surgeries in female urology, transvaginal excision of urethral diverticulum needs careful and meticulous procedures in order to avoid some operative complications, such as urethral stricture or urethrovaginal fistula. In the present report, we present a woman with urethral diverticulum who initially underwent transvaginal excision of diverticulum in the dorsal lithotomy position, but she was complicated with urethrovaginal fistula postoperatively. Unfortunately, we failed to repair her fistula when she underwent excision of the fistula in the dorsal lithotomy position. With reconsideration of an operative position useful for transvaginal surgery, we succeeded in fistula closure in the Jackknife prone reverse-lithotomy position, and thereafter, two subsequent patients with urethral diverticulum were successfully treated with transvaginal excision of diverticulum in this operative position. In the transvaginal approach to the peri-urethral disorders, the Jackknife prone reverse-lithotomy position was notably superior to the dorsal lithotomy position with the following advantages: (1) the surgeons can easily operate in a bright and large surgical site without any blind view. (2) the surgeons can dissect and suture safely and accurately. (3) the assistants also can help in the operation bimanually in the same view as the surgeon when the posterior vaginal wall is fixed with a retractor.

Adult↗

PubMed2005

Nocturia in men with lower urinary tract symptoms is associated with both nocturnal polyuria and detrusor overactivity with positive response to ice water test.

OBJECTIVES: To investigate whether detrusor overactivity (DO) and the response to the ice water test (IWT) influence nighttime urinary frequency in patients with lower urinary tract symptoms. METHODS: A total of 114 patients with lower urinary tract symptoms, who were older than 50 years, with an International Prostate Symptom Score 8 or more points and a quality of life index of 2 or greater, were evaluated by a 48-hour frequency-volume chart, free flowmetry, pressure flow study, and IWT. RESULTS: The DO-positive IWT responders had a significantly greater bladder outlet obstruction index than did the DO-positive IWT nonresponders and the DO-negative IWT nonresponders. The DO-positive IWT responders had significantly more frequent nocturia and smaller nighttime maximal and minimal voided volumes than did the DO-negative IWT nonresponders without any difference in the nocturnal voided volume. The patients with nocturia two or more times had a significantly larger nocturnal voided volume and smaller nighttime minimal voided volume than the patients with nocturia less than two times. The incidence of DO-positive IWT responders was significantly greater among the patients with nocturia three or more times than that among those with nocturia less than three times. In the multivariate logistic model, the nocturnal voided volume and nighttime minimal voided volume were independently associated with nocturia two or more times and the DO-positive IWT responders were independently associated with nocturia three or more times. CONCLUSIONS: Once high-grade bladder outlet obstruction induces C-fiber-related DO, it is strongly suggested that this process, together with nocturnal polyuria, plays an important role in the consequent clinical manifestations of nocturia in patients with lower urinary tract symptoms.

Administration, Intravesical↗

PubMed2005

[A case of primary and solitary bone metastasis of testicular seminoma after orchiectomy].

A 40-year-old man with stage I left testicular seminoma who had been followed for 18 months after orchiectomy, complained of pain in his left upper extremity and dysbasia. Magnetic resonance imaging (MRI) and bone scintigraphy suggested multiple bone lesions in the thoracic vertebrae and right ischium, and bone biopsy revealed metastasis of seminoma. There was no evidence of other metastatic lesions. After he was treated with 2 courses of first-line chemotherapy consisting of peplomycin, etoposide, and cisplatin, which were followed by 2 courses of high-dose chemotherapy with carboplatin, etoposide, and ifosfamide, the metastatic lesions were nearly in complete response on MRI and bone scintigraphy and the result of fluorodeoxyglucose-positron emission tomography was negative, but the hCG-beta level remained slightly elevated. In most advanced testicular tumors, bone metastasis usually coexists with other metastatic lesions and appears as a secondary lesion. Herein, we report this rare case of primary and solitary bone metastasis from testicular seminoma after orchiectomy.

Adult↗

PubMed2004

Alpha-blocker test: alternative to pressure-flow study of bladder outlet obstruction and detrusor contractility in patients without an enlarged prostate.

OBJECTIVES: We investigated whether the cause of urinary disturbance in men with a prostate volume < or =20 mL can be determined by analyzing the efficacy of alpha1-adrenoceptor antagonist (alpha-blocker) treatment. METHODS: Thirty-five men who were >50 years of age, with an International Prostate Symptom Score (IPSS) > or =8 points, a quality of life (QOL) index > or =2 points and a prostate volume </=20 mL were enrolled in the non-enlarged prostate group. Twenty-six men who met the above conditions but who had a prostate volume >20 mL served as controls. The alpha1-adrenoceptor antagonist tamsulosin was administered at a dose of 0.2 mg/day for 4 weeks. Results for the IPSS, QOL index, free flowmetry and pressure-flow studies were obtained before and after tamsulosin administration. RESULTS: In both groups, tamsulosin improved the IPSS and QOL index and the bladder outlet obstruction index (BOOI) was lowered without reducing the bladder contractility index (BCI). No parameter showed a significant difference in treatment efficacy between the two groups. In the non-enlarged prostate group, both the pretreatment BOOI and BCI correlated with the efficacy of treatment in improving maximum flow rate (Qmax). In the enlarged prostate group, BOOI and BCI did not correlate with Qmax. When Qmax was improved by > or =3.5 mL/s, the positive predictive value for both pretreatment BOOI >40 and BCI >100 was 100% in the non-enlarged prostate group. CONCLUSIONS: The alpha-blocker test is one method to assess the presence of bladder outlet obstruction and the state of detrusor contractility in men without an enlarged prostate.

Adrenergic alpha-Antagonists↗

PubMed2004

[A case of intrapelvic retroperitoneal ganglioneuroma].

A 61-year-old man presented with an asymptomatic intrapelvic retrovesical tumor, measuring 8.5 cm in maximum diameter, which was revealed by preoperative diagnostic imaging for transverse colon cancer. When he was referred to our department one year after hemi-colectomy, this tumor showed no change in size, but there was some suspicion of concomitant malignancy because of large tumor size and contrast enhancement in a region adherent to the right seminal vesicle. En-bloc resection of the tumor along with the right seminal vesicle was performed retroperitoneally. The tumor was diagnosed histopathologically as retroperitoneal ganglioneuroma. Herein, we report this rare case of intrapelvic retroperitoneal ganglioneuroma, and present a brief review of the relevant literature including the present case.

Adult↗

PubMed2004

[A case of retrovesical leiomyoma].

We herein report a rare case of leiomyoma in the retroperitoneal space posterior to the urinary bladder. A 61-year-old man came to our department complaining of lower abdominal discomfort. Abdominal and pelvic computed tomographic scan revealed a retrovesical solid tumor on the cranial side to the left seminal vesicle. Diagnostic imaging suggested that the retrovesical tumor was a benign tumor such as leiomyoma or fibroma, and he underwent simple resection of this retrovesical tumor via reroperitoneal approach. Histopathological diagnosis was well compatible with image diagnosis of leiomyoma. He has been followed up for 6 months without recurrence.

Gadolinium DTPA↗

PubMed2003

Positive response to ice water test associated with high-grade bladder outlet obstruction in patients with benign prostatic hyperplasia.

OBJECTIVES: To elucidate the clinical significance of detrusor overactivity (DO) that is probably due to C-fiber activation caused by bladder outlet obstruction (BOO), we examined the responses to the ice water test (IWT) in patients with benign prostatic hyperplasia (BPH) and assessed the results with reference to the clinical manifestations and urodynamic findings. METHODS: A total of 127 patients without neurologic disease, who were older than 50 years of age, with an International Prostate Symptom Score of 8 points or greater and a quality of life index of 2 or more points, were enrolled in this study. We tested the response to ice water instillation by monitoring the intravesical pressure in all cases and assessed the results with reference to the findings of International Prostate Symptom Score and quality of life index questionnaires, BOO indexes, 48-hour frequency volume charts, prostate volume, and data from free-flowmetry and pressure flow studies for detecting DO. Twenty patients with neurogenic bladder dysfunction underwent IWT as a control group. RESULTS: The responders to the IWT accounted for 14 (70%) of the 20 patients with neurogenic bladder dysfunction and 35 (27%) of the 127 patients without neurologic disease. All of these responders showed DO on the pressure flow studies. The patients without neurologic disease who responded to the IWT had higher BOO indexes than did the nonresponders and had a smaller volume at a maximal desire to void on the urodynamic studies. The largest single-voided volume recorded from the 48-hour frequency volume charts was also smaller for the responders than for the nonresponders. CONCLUSIONS: The patients with BPH clearly showed that DO was mainly due to active C-fibers stimulated by high-grade BOO and that DO was a cause of urgency and frequency-related symptoms with decreased bladder capacity. It will be necessary to assess the inhibitory effect of capsaicin on DO caused by activation of C-fibers and the reversibility of C-fiber activation after surgical treatment for BPH, so that the criteria for decision-making for the treatment of BPH may be clarified with the aid of the IWT.

Administration, Intravesical↗

PubMed2003

Aggressive angiomyxoma in the scrotum expressing androgen and progesterone receptors.

Aggressive angiomyxoma is a rare benign mesenchymal myxoid tumor that arises from the pelvic soft tissues and perineum in relatively young females. This tumor has the ability to infiltrate locally and has a high risk of local recurrence after extirpation, but no potential to metastasize. We report here a rare case of aggressive angiomyxoma that developed in the scrotum of a 47-year-old male. Immunostaining of the resected specimen revealed that the tumor cell nuclei stained strongly and diffusely for androgen receptors (80% of the tumor cells), and moderately and partly for progesterone receptors (20% of the tumor cells). However, staining was negative for estrogen receptors. It is highly suggested that the growth of aggressive angiomyxoma in males may depend on androgen manipulation, contrary to its frequent and close association with estrogen receptor expression, which has been reported in females.

Genital Neoplasms, Male↗

PubMed2003

[A case of inflammatory myofibroblastic tumor of the retroperitoneum].

Here we report a rare case of inflammatory myofibroblastic tumor of the retroperitoneal space. A 46-year-old woman had had microscopic hematuria for 5 years. Ultrasonographic examination for screening revealed two solid tumors adjacent to the right kidney. These tumors were suspected to be malignant fibrous histiocytoma or liposarcoma by computed tomography and magnetic resonance imaging. She underwent resection of these retroperitoneal tumors and additional right nephrectomy because these tumors were adhered to the kidney and liposarcoma was highly suspected on frozen sections. Histopathologic examination finally revealed that the tumors were inflammatory myofibroblastic tumor arising within Gerota's fasia. She has been followed up for 9 months without any evidence of local recurrence.

Diagnosis, Differential↗

PubMed2003

[Non-ischemic tumor enucleation for renal angiomyolipoma: a case report].

A case of renal angiomyolipoma, successfully treated with non-ischemic tumor enucleation, is reported. A 16-year-old Japanese female visited another hospital with a chief complaint of general fatigue. She was diagnosed with angiomyolipoma of the right kidney, 7 cm in the long axis, which developed exteriorly at the lower pole. A nephrectomy was recommended. The patient visited us for a second opinion. We judged that nephron-sparing surgery was applicable to this case. The patient underwent non-ischemic tumor enucleation using a microwave tissue coagulator via retroperitoneal approach. The patient was discharged from our hospital 9 days after the surgery. Since a preoperative diagnosis with renal angiomyolipoma can be obtained relatively easily, maximum efforts for nephron-sparing surgery should be made.

Adolescent↗

PubMed2002

Spontaneously ruptured multilocular cystic nephroma.

Multilocular cystic nephroma is a relatively rare benign tumor of the kidney. An adult case of spontaneously ruptured multilocular cystic nephroma was reported. A 33-year-old woman who presented with a right flank colic attack. The preoperative diagnosis was spontaneously ruptured renal tumor. A right nephrectomy was performed. A multilocular cystic lesion, 10 cm in diameter, was found in the removed specimen, which had a hematoma inside and direct tumor extension into the renal pelvis. On microscopic examination, the surface of loculi was covered by a layer of hobnail epithelium, and septa were composed of fibrous tissue with dilated vessels, lacking in normal renal components. There were no signs of malignancy. The lesion extending into the renal pelvis showed the same microscopic findings. The final diagnosis was multilocular cystic nephroma. Two respects, spontaneous rupture and tumor extension into the renal pelvis, were unique to the present case. There has been no report of spontaneously ruptured mutilocular cystic nephroma. The tumor extension into the renal pelvis, however, has been found in several reports. This growth pattern might be one of the characteristics of this benign renal tumor.

Adult↗

PubMed2002

Comparison of parameters to determine the cause of urinary disturbance in men with prostate volume less than 20 milliliters.

BACKGROUND: A pressure-flow study, although a slightly invasive procedure, can evaluate bladder outlet obstruction and detrusor contractility. This study was conducted in men with a non-enlarged prostate to determine the cause of urinary disturbance by less invasive examinations that might eventually replace pressure-flow study. METHODS: Thirty-six men with lower urinary tract symptoms were enrolled. Their prostate volume, estimated by transrectal ultrasonography, was less than 20 mL. All patients were examined using pressure-flow study, free-flowmetry, transrectal ultrasonography, prostate specific antigen and an interview using the International Prostate Symptom Score and Quality of Life Index. With determination of the cause for urinary disturbance, parameters that correlated with outflow obstruction or impaired detrusor contractility were sought. RESULTS: Twenty-one (60%) of the 36 men were judged as having outflow obstruction, and 16 of these 21 men had normal detrusor function. Impaired detrusor contractility was observed in 17 men. Only three of these 17 men had no outflow obstruction. Four patients had an unstable bladder. All these four had normal detrusor contractility, but had outflow obstruction. Among the parameters examined, only the maximum flow rate in a flow metrogram (Qmax) correlated significantly with the degree of outflow obstruction (P = 0.04). The positive predictive value of Qmax for outflow obstruction was 65% at a flow rate of less than 10 mL/s, and 100% at that of less than 5 mL/s. No parameter correlated with detrusor contractility. CONCLUSION: The only parameter that was a clear indicator of outflow obstruction was Qmax. Other indicators of detrusor contractility should be sought.

Aged↗