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2.
Adv Exp Med Biol ; 1288: 287-306, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34453742

RESUMEN

Testicular torsion (TT) is a common urologic emergency that can occur at any age. It is most common in newborns and during puberty. Prompt evaluation and management is required to salvage the testis following an episode of torsion. TT brings about damage to testicular tissue and spermatogenesis through various hypothesized mechanisms; however there is a consensus that the effects of ischemia, ischemia-reperfusion injury, and oxidative stress account for the most destructive effects. Numerous studies have examined the effects of various agents and therapies in limiting the effects of TT on the testis.


Asunto(s)
Daño por Reperfusión , Torsión del Cordón Espermático , Animales , Humanos , Recién Nacido , Masculino , Ratas , Ratas Sprague-Dawley , Espermatogénesis , Testículo
3.
F S Rep ; 2(2): 176-180, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34278351

RESUMEN

OBJECTIVE: To assess if the newer Kruger strict morphology (WHO5; normal ≥4%) adds any clinical value beyond the criteria of the World Health Organization fourth edition (WHO4; normal ≥14%). DESIGN: Retrospective study. SETTING: Tertiary hospital. PATIENTS: Men without known azoospermia who had semen analysis (SA) collected over a 10-year period of time. INTERVENTIONS: Morphology classification under Kruger WHO5 strict criteria and WHO4 criteria. MAIN OUTCOME MEASURES: Correlation between the WHO5 and WHO4 morphological classifications. RESULTS: A total of 4,510 SAs were identified during the study period. Of these, both Kruger WHO5 and WHO4 morphologies were included in 932 SAs (20.7%) from a total of 691 men. The median age of the men was 37 years (interquartile range, 32.0-43.8 years). The mean (±SD) semen volume, sperm concentration, and motility were 2.6 ± 1.4 mL, 50.0 ± 35.6 × 106/mL, and 53.1% ± 18.6%, respectively. The correlation between the WHO4 and WHO5 morphology assessments was high (Spearman correlation coefficient = 0.94). Only 545 (58.5%) of 932 SAs had abnormal Kruger WHO5 morphology, of which 543 (99.6%) of 545 also had abnormal morphology by the WHO4 criteria. CONCLUSIONS: The Kruger WHO5 and WHO4 morphologic criteria correlate closely. Only two men (0.4%) with an abnormal Kruger morphology had normal WHO4 morphology. Given the limited predictive value of sperm morphology, the additional cost and effort of Kruger criteria may not be warranted in lieu of, or in addition to, the WHO4 classification.

4.
Urol Pract ; 8(3): 337-340, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-37145658

RESUMEN

INTRODUCTION: Vasectomy is the most effective form of permanent male contraception. Although vasectomy techniques and outcomes have steadily improved, postvasectomy semen analysis compliance remains a significant challenge. The aim of this study was to assess if home testing improved postvasectomy semen analysis compliance. METHODS: Data were collected prospectively but retrospectively reviewed between 2007 and 2019 from a single surgeon's high volume practice. Subjects were divided into 2 groups based on postvasectomy semen analysis method (home vs office) and further subdivided by compliance status. Patients were considered compliant if they provided at least 1 semen sample postvasectomy. Statistical analysis was completed to determine factors predictive of compliance. RESULTS: A total of 364 patients were included. Median age for the home group vs the office group was similar (42 years [IQR 39-46] vs 41 years [IQR 38-46]). Median number of children for both groups was 2 (IQR 2-3). In all, 109 men (30.0%) opted for at-home testing. No significant difference in compliance was found (59.6% of home test vs 58.8% of laboratory patients, p=0.89). No statistically significant difference in patient demographics (age, partner age, number of children, smoking and alcohol) was observed, and there were no demographic factors predicting compliance with regression modeling. CONCLUSIONS: At-home semen analysis kits did not significantly improve compliance. Clinicians should be aware that this may be a reasonable alternative for those who are unable to obtain a postvasectomy semen analysis in-office. Contact of the female partner instead may improve postvasectomy semen analysis compliance as the female partner has a stake in ensuring postvasectomy semen analysis azoospermia.

5.
J Urol ; 205(1): 236-240, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32716681

RESUMEN

PURPOSE: We retrospectively evaluated the utility of sperm cryopreservation at the time of vasectomy reversal. MATERIALS AND METHODS: From April 2016 through December 2018 a total of 26 men underwent vasectomy reversal. Sperm cryopreservation is routinely offered at the time of vasectomy reversal at our institution. We sought to assess utilization of cryopreserved sperm by those men with early or late vasectomy reversal failure. RESULTS: Of 26 patients presenting for vasectomy reversal 22 (85%) elected to cryopreserve sperm. Sperm were obtained for freezing from the vasal (7 patients) or epididymal fluid (3), or via testicular biopsy (12). Three patients were lost to followup postoperatively. Of the 23 who presented for post-procedure followup 19 either had semen analyses with motile sperm or a live birth (83% success rate). There were 4 early failures and 2 late failures; all patients with failures had elected to cryopreserve sperm at the time of initial reversal. Three of the 6 individuals (50%) with vasectomy reversal failure elected to use cryopreserved sperm for in vitro fertilization/intracytoplasmic sperm injection, with 2 of these (67%) resulting in live births. CONCLUSIONS: Of those patients who experienced vasectomy reversal failure 50% elected to use cryopreserved sperm that had been procured at the time of initial reversal. Given the potential for early or late failure, cryopreservation of sperm at the time of vasectomy reversal should be routinely offered as a means of avoiding the added expense and potential morbidity of future surgical sperm retrieval.


Asunto(s)
Criopreservación , Recuperación de la Esperma , Espermatozoides , Vasectomía/efectos adversos , Vasovasostomía/efectos adversos , Adulto , Femenino , Humanos , Nacimiento Vivo , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Análisis de Semen , Inyecciones de Esperma Intracitoplasmáticas/estadística & datos numéricos , Insuficiencia del Tratamiento , Vasovasostomía/métodos
6.
Expert Rev Endocrinol Metab ; 14(6): 369-380, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31587581

RESUMEN

Introduction: Klinefelter syndrome (KS) represents the most common chromosomal abnormality in the general population, and one of the most common genetic etiologies of nonobstructive azoospermia (NOA) and in severe oligospermia. Once considered untreatable, men with KS and NOA now have a variety of treatment options to obtain paternity.Areas covered: The cornerstone of treatment for both KS and NOA patients remains the surgical retrieval of viable sperm, which can be used for intracytoplasmic sperm injection to obtain pregnancy. Although the field has advanced significantly since the early 1990s, approximately half of men with KS will ultimately fail fertility treatments. Presented is a critical review of the available evidence that has attempted to identify predictive factors for successful sperm recovery. To optimize surgical success, a variety of treatment modalities have also been suggested and evaluated, including hormonal manipulation and timing of retrieval.Expert opinion: Individuals with KS have a relatively good prognosis for sperm recovery compared to other men with idiopathic NOA. Surgical success is heavily dependent upon surgical technique and the experience of the andrology/embryology team tasked with the identification and use of testicular sperm.


Asunto(s)
Azoospermia/etiología , Preservación de la Fertilidad , Síndrome de Klinefelter/fisiopatología , Preservación de Semen , Recuperación de la Esperma , Azoospermia/complicaciones , Humanos , Síndrome de Klinefelter/complicaciones , Síndrome de Klinefelter/tratamiento farmacológico , Masculino , Inyecciones de Esperma Intracitoplasmáticas , Testículo , Testosterona/efectos adversos , Testosterona/uso terapéutico
7.
J Assoc Res Otolaryngol ; 20(4): 313-339, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31165284

RESUMEN

To better understand the spread of prosthetic current in the inner ear and to facilitate design of electrode arrays and stimulation protocols for a vestibular implant system intended to restore sensation after loss of vestibular hair cell function, we created a model of the primate labyrinth. Because the geometry of the implanted ear is complex, accurately modeling effects of prosthetic stimuli on vestibular afferent activity required a detailed representation of labyrinthine anatomy. Model geometry was therefore generated from three-dimensional (3D) reconstructions of a normal rhesus temporal bone imaged using micro-MRI and micro-CT. For systematically varied combinations of active and return electrode location, the extracellular potential field during a biphasic current pulse was computed using finite element methods. Potential field values served as inputs to stochastic, nonlinear dynamic models for each of 2415 vestibular afferent axons, each with unique origin on the neuroepithelium and spiking dynamics based on a modified Smith and Goldberg model. We tested the model by comparing predicted and actual 3D vestibulo-ocular reflex (VOR) responses for eye rotation elicited by prosthetic stimuli. The model was individualized for each implanted animal by placing model electrodes in the standard labyrinth geometry based on CT localization of actual implanted electrodes. Eye rotation 3D axes were predicted from relative proportions of model axons excited within each of the three ampullary nerves, and predictions were compared to archival eye movement response data measured in three alert rhesus monkeys using 3D scleral coil oculography. Multiple empirically observed features emerged as properties of the model, including effects of changing active and return electrode position. The model predicts improved prosthesis performance when the reference electrode is in the labyrinth's common crus (CC) rather than outside the temporal bone, especially if the reference electrode is inserted nearly to the junction of the CC with the vestibule. Extension of the model to human anatomy should facilitate optimal design of electrode arrays for clinical application.


Asunto(s)
Oído Interno/fisiología , Estimulación Eléctrica , Electrodos Implantados , Macaca mulatta/fisiología , Modelos Teóricos , Animales , Oído Interno/cirugía , Femenino , Macaca mulatta/cirugía , Masculino
8.
Fertil Steril ; 111(3): 444-453, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30827518

RESUMEN

Men seeking fertility after elective sterilization can be treated with a wide array of interventions. Reconstruction of the reproductive tract remains the gold standard and most cost-effective option for the appropriately selected candidate. In the following review, the treatment algorithm for men desiring vasectomy reversal is outlined. Specifically, the current evidence basis for preoperative evaluation, intraoperative decision making, postsurgical management, and emerging advances to optimize outcomes will be discussed. Finally, the important role of microsurgical training and how the field can improve quality of care will be reviewed.


Asunto(s)
Microcirugia , Vasovasostomía/métodos , Competencia Clínica , Toma de Decisiones Clínicas , Educación de Postgrado en Medicina , Fertilidad , Humanos , Masculino , Microcirugia/efectos adversos , Microcirugia/educación , Recuperación de la Función , Resultado del Tratamiento , Vasovasostomía/efectos adversos , Vasovasostomía/educación
9.
Curr Urol Rep ; 19(7): 56, 2018 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-29774489

RESUMEN

PURPOSE OF REVIEW: Increasing attention to primary and secondary prevention of male infertility through modifiable lifestyle factors has gained traction amongst both patients and infertility specialists. In this review, the available evidence of modifiable lifestyle choices, specifically diet, physical activity, and body habitus, are evaluated. RECENT FINDINGS: Studies examining diet, exercise/physical activity, and body habitus are characterized by conflicting conclusions, difficult confounders, and imperfect end points to judge male reproductive potential. However, convincing trends have emerged implicating consumption of saturated fats, pesticide exposure, high intensity exercise, and extremes of body mass index as detrimental to male fertility. Data assessing modifiable risk factors and subfertility in male partners has emphasized the notion of moderation. Balancing dietary fat, moderation of physical activity, and the management of a healthy body habitus favor both improvement of semen quality and birth outcomes. These observations provide actionable data for the reproductive urologist to better counsel men presenting with infertility.


Asunto(s)
Dieta , Ejercicio Físico , Infertilidad Masculina/etiología , Infertilidad Masculina/prevención & control , Estilo de Vida , Índice de Masa Corporal , Humanos , Masculino
11.
J Urol ; 196(6): 1715-1720, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27287525

RESUMEN

PURPOSE: We studied the incidence and risk factors for the development of erythrocytosis with implantable testosterone pellets. MATERIALS AND METHODS: A multi-institutional retrospective database analysis was used to evaluate men treated with testosterone pellets between 2009 and 2014. Inclusion criteria consisted of adult, hypogonadal males who had a full complement of pretreatment and posttreatment surveillance studies. Pretreatment and posttreatment values were compared with Wilcoxon signed rank tests. Multiple linear regression was used to identify potential risk factors for significant hematocrit elevation. RESULTS: A total of 97 patients were included in the study. The average age of the cohort was 52 years (range 24 to 80). Mean hematocrit before and after pellet implantation was 43.9% and 46.1%, respectively, corresponding to an increase of 2.2% (CI 1.4-2.9, p <0.001). The average increase in testosterone was 145.3 ng/dl from an initial mean of 278.9 ng/dl (CI 105.7-184.9, p <0.001). Multiple linear regression demonstrated that pretreatment hematocrit was inversely related to the expected change in hematocrit. Pretreatment comorbidity status (ie the presence of hypertension, hyperlipidemia, obesity or diabetes) was not associated with a significant increase in posttreatment hematocrit. CONCLUSIONS: Although the data demonstrate a statistically significant increase in hematocrit, an increment of 2.2% is unlikely to translate into clinical relevance. Thus, for this cohort of patients implantable testosterone pellets appear safe in terms of the risk of polycythemia. Pretreatment hematocrit may serve as a predictor of a significant hematocrit increase after the initiation of therapy.


Asunto(s)
Hematócrito , Hipogonadismo/tratamiento farmacológico , Policitemia/inducido químicamente , Policitemia/epidemiología , Testosterona/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Implantes de Medicamentos , Humanos , Masculino , Persona de Mediana Edad , Policitemia/sangre , Estudios Retrospectivos , Factores de Riesgo , Testosterona/administración & dosificación
12.
Urol Clin North Am ; 43(2): 223-32, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27132580

RESUMEN

Varicocele is defined as an excessive dilation of the pampiniform plexus. The association between varicocele and infertility has been well-established as evidenced by negative effects on spermatogenesis. Accumulating evidence now suggests that varicocele presents a pantesticular insult, with resultant impairment of Leydig cell function. The presence of a varicocele has been linked to lower serum testosterone levels and varicocelectomy may reverse some of the adverse effects on androgen production. In this review, the evidence linking varicoceles to impaired steroidogenesis and which cohorts of men may benefit most from varicocele repair are discussed.


Asunto(s)
Trastorno del Desarrollo Sexual 46,XY/fisiopatología , Hipogonadismo/fisiopatología , Testículo/anomalías , Testosterona/fisiología , Varicocele/fisiopatología , Trastorno del Desarrollo Sexual 46,XY/sangre , Humanos , Hipogonadismo/sangre , Hipogonadismo/etiología , Masculino , Testículo/fisiopatología , Testosterona/sangre , Varicocele/sangre , Varicocele/complicaciones , Varicocele/cirugía
13.
Fertil Res Pract ; 2: 7, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28620534

RESUMEN

BACKGROUND: Sperm quality may degrade during transit through the male reproductive tract in some individuals. In this setting surgically retrieved testicular sperm may outperform ejaculated samples for use with in vitro fertilization (IVF) and intracytoplasmic sperm injection (IVF-ICSI). We sought to describe one center's experience with the use of fresh testicular sperm after prior failed IVF-ICSI with ejaculated samples. RESULTS: A retrospective review was conducted evaluating IVF-ICSI cycles performed at a tertiary IVF unit between 2009 and 2014. Couples who were managed with percutaneous testis biopsy to obtain sperm, despite availability of ejaculated sperm, were included. Four couples who underwent a total of 6 percutaneous testis biopsy/IVF-ICSI cycles were identified. Collectively, the couples had undergone 9 prior IVF-ICSI cycles using fresh ejaculated sperm without successful pregnancy. From the six cycles that used fresh testicular sperm four live births resulted (1 twin gestation, 3 singletons). Only 1 of the 4 couples remained childless. CONCLUSIONS: For patients who have had prior failed IVF-ICSI attempts, this small case series demonstrates a possible therapeutic benefit when freshly procured testicular sperm are used in lieu of ejaculated samples.

14.
Urol Pract ; 2(1): 33-37, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37537825

RESUMEN

INTRODUCTION: Obstructive azoospermia represents a treatable form of male factor infertility. With greater demand for assisted reproductive technologies the general urologist may be tasked with initiating the infertility evaluation and providing counsel for treatment options. In this review we discuss appropriate laboratory, radiographic and genetic testing for the patient with obstructive azoospermia. We also outline surgical treatment options. METHODS: The Medline® database was searched for relevant studies of the evaluation and treatment of men with obstructive azoospermia. Key words included obstructive azoospermia, vasovasostomy, vasoepididymostomy, testicular sperm extraction, sperm aspiration and sperm retrieval. RESULTS: Most published reports were based on small cohorts followed at single institutions. There were sufficient data to characterize the current state of the art and review the standard of practice. CONCLUSIONS: The initial evaluation of azoospermia is primarily based on differentiating obstructive from nonobstructive etiologies with a substantial reliance on history, physical examination and screening laboratory studies. Various treatment options exist for obstructive azoospermia, including reproductive tract reconstruction (vasovasostomy or vasoepididymostomy) or numerous surgical sperm extraction approaches.

15.
Asian J Urol ; 2(2): 85-91, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29264125

RESUMEN

Nonobstructive azoospermia (NOA) is characterized by the complete absence of sperm in the ejaculate due to testicular failure. The evaluation and management of patients with NOA offer a challenge to the reproductive urologist. In the era of in vitro fertilization with intracytoplasmic sperm injection, surgical sperm extraction techniques can afford men with NOA biologic paternity. To provide a comprehensive review of surgical sperm retrieval approaches in the patient with NOA emphasizing complications, success rates and outcome optimization, a Medline search was conducted querying surgical approaches used to manage NOA. Four sperm extraction techniques are described including: testicular sperm aspiration, testicular sperm extraction, fine needle aspiration mapping and microdissection testicular sperm extraction. In addition, the roles for pre-extraction varicocelectomy and sperm cryopreservation are discussed. The management of NOA continues to evolve as newer tools become available. Several modalities of sperm acquisition exist. An understanding of their complications and success rates is fundamental to the treatment of NOA.

17.
Exp Brain Res ; 210(3-4): 623-40, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21380738

RESUMEN

To facilitate design of a multichannel vestibular prosthesis that can restore sensation to individuals with bilateral loss of vestibular hair cell function, we created a virtual labyrinth model. Model geometry was generated through 3-dimensional (3D) reconstruction of microMRI and microCT scans of normal chinchillas (Chinchilla lanigera) acquired with 30-48 µm and 12 µm voxels, respectively. Virtual electrodes were positioned based on anatomic landmarks, and the extracellular potential field during a current pulse was computed using finite element methods. Potential fields then served as inputs to stochastic, nonlinear dynamic models for each of 2,415 vestibular afferent axons with spiking dynamics based on a modified Smith and Goldberg model incorporating parameters that varied with fiber location in the neuroepithelium. Action potential propagation was implemented by a well validated model of myelinated fibers. We tested the model by comparing predicted and actual 3D angular vestibulo-ocular reflex (aVOR) axes of eye rotation elicited by prosthetic stimuli. Actual responses were measured using 3D video-oculography. The model was individualized for each animal by placing virtual electrodes based on microCT localization of real electrodes. 3D eye rotation axes were predicted from the relative proportion of model axons excited within each of the three ampullary nerves. Multiple features observed empirically were observed as emergent properties of the model, including effects of active and return electrode position, stimulus amplitude and pulse waveform shape on target fiber recruitment and stimulation selectivity. The modeling procedure is partially automated and can be readily adapted to other species, including humans.


Asunto(s)
Electrodos Implantados , Modelos Anatómicos , Reflejo Vestibuloocular/fisiología , Interfaz Usuario-Computador , Vestíbulo del Laberinto/fisiología , Potenciales de Acción/fisiología , Vías Aferentes/fisiología , Animales , Biofisica , Conducción Ósea , Chinchilla , Estimulación Eléctrica/métodos , Movimientos de la Cabeza , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética , Rotación , Tomografía Computarizada por Rayos X
18.
Artículo en Inglés | MEDLINE | ID: mdl-22255006

RESUMEN

Bilateral loss of vestibular sensation causes difficulty maintaining stable vision, posture and gait. An implantable prosthesis that partly restores normal activity on branches of the vestibular nerve should improve quality of life for individuals disabled by this disorder. We have developed a head-mounted multichannel vestibular prosthesis that restores sufficient semicircular canal function to partially recreate a normal 3-dimensional angular vestibulo-ocular reflex in animals. Here we describe several parallel lines of investigation directed toward refinement of this approach toward eventual clinical application.


Asunto(s)
Estimulación Eléctrica , Prótesis e Implantes , Reflejo Vestibuloocular/fisiología , Vestíbulo del Laberinto , Humanos
19.
Cochlear Implants Int ; 11 Suppl 2: 2-11, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21756683

RESUMEN

Bilateral loss of vestibular sensation can disable individuals whose vestibular hair cells are injured by ototoxic medications, infection, Ménière's disease or other insults to the labyrinth including surgical trauma during cochlear implantation. Without input to vestibulo-ocular and vestibulo-spinal reflexes that normally stabilize the eyes and body, affected patients suffer blurred vision during head movement, postural instability, and chronic disequilibrium. While individuals with some residual sensation often compensate for their loss through rehabilitation exercises, those who fail to do so are left with no adequate treatment options. An implantable neuroelectronic vestibular prosthesis that emulates the normal labyrinth by sensing head movement and modulating activity on appropriate branches of the vestibular nerve could significantly improve quality of life for these otherwise chronically dizzy patients. This brief review describes the impact and current management of bilateral loss of vestibular sensation, animal studies supporting the feasibility of prosthetic vestibular stimulation, and a vestibular prosthesis designed to restore sensation of head rotation in all directions. Similar to a cochlear implant in concept and size, the Johns Hopkins Multichannel Vestibular Prosthesis (MVP) includes miniature gyroscopes to sense head rotation, a microcontroller to process inputs and control stimulus timing, and current sources switched between pairs of electrodes implanted within the vestibular labyrinth. In rodents and rhesus monkeys rendered bilaterally vestibulardeficient via treatment with gentamicin and/or plugging of semicircular canals, the MVP partially restores the vestibulo-ocular reflex for head rotations about any axis of rotation in 3-dimensional space. Our efforts now focus on addressing issues prerequisite to human implantation, including refinement of electrode designs and surgical technique to enhance stimulus selectivity and preserve cochlear function, optimization of stimulus protocols, and reduction of device size and power consumption.


Asunto(s)
Prótesis Neurales , Enfermedades Vestibulares/terapia , Vestíbulo del Laberinto , Animales , Modelos Animales de Enfermedad , Mareo , Humanos , Modelos Neurológicos , Equilibrio Postural , Enfermedades Vestibulares/diagnóstico , Enfermedades Vestibulares/epidemiología , Vestíbulo del Laberinto/inervación
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