Miguel Castellan | University of Miami (original) (raw)

Papers by Miguel Castellan

Urology case reports, Nov 1, 2018

Neurosurgery, Sep 1, 1999

Introduction: To determine risk factors for endoscopic third ven triculostomy (ETV) failure, Kapl... more Introduction: To determine risk factors for endoscopic third ven triculostomy (ETV) failure, Kaplan-Meier estimates of recurrence-free time were compared statistically with log rank test. Methods: Eighty-nine patients (52 new, 37 previously shunted) with obstructive hydrocephalus, who underwent ETV from 1994 to 1998, were reviewed. The factors analyzed were age, gender, etiology of hydrocephalus, location of CSF obstruction, presence of concurrent VP/VA shunts, history of shunt revisions or infections, preoperative symptoms, pre and postoperative imaging (ventricular size and CSF flow on cine MRI) and postoperative meningitis. Results: Twenty-nine patients (32.6%) required subsequent shunt ing and/or redo ETV. Among these 29 re-operations, 12 procedures (41.4%) were performed within 2 weeks, and only 3 greater than 18 months post-ETV. The ventricular size remained unchanged in 75% of cases the day following ETV, 48.2% at 6 months and 41.8% at 1 year. Seven complications (7.9%) occurred but were all transient. Risk of ETV failure increased with Chiari or Dandy-Walker malformations (relative risk 2.7, p =0.013), shunt infection at presentation (relative risk 2.9, p=0.0090), history of shunt infections (relative risk 6.2, p=0.0004), three or more previous shunt revisions (relative risk 4.6, p=0.0018) and postoperative meningitis (relative risk 4.1, p =0.0001). Late-onset idiopathic aqueductal stenosis is a significant predictor of good outcome (relative risk 0.40, p =0.044). Postoperative cine MRI can confirm ventriculostomy patency in 96.3% of patients with symp tom resolution. Conclusion: ETV can be performed safely with a low level of morbidity. The significant risk factors for failure are Chiari or Dandy-Walker malformations and intracerebral infections.

Urology, Jun 1, 2005

Augmentation cystoplasty operations using segments of gastrointestinal tract are often necessary ... more Augmentation cystoplasty operations using segments of gastrointestinal tract are often necessary in neurogenic low-compliance bladders. Patients are usually rehabilitated with an increase in storage volume and normalization of the reduced compliance. However, gut mucosa-related early and late complications are not very uncommon. Malignancy, although rare, is known to occur after enterocystoplasty, but only one such case has been reported for gastrocystoplasty, a single patient who developed urothelial carcinoma. We describe what we believe to be the first case of signet ring cell carcinoma developing after gastrocystoplasty.

The Journal of Urology, Apr 1, 2004

stable, but not resolved HUN at 8 years of followup, suffered significant asymptomatic worsening ... more stable, but not resolved HUN at 8 years of followup, suffered significant asymptomatic worsening in the degree of HUN and diminished renal function on one side and a renal stone on the contralateral renal unit at 14 year followup. CONCLUSIONS: Our long-term follow-up of children with antenatally diagnosed POM with mild to moderate pelviectasis confirms a high incidence of resolution and improvement. As we have documented I case of worsening of HUN at 14 year follow-up, we believe that ultrasonography should be periodically obtained until the child reaches adulthood at least in cases where complete resolution in HUN is not documented.

The Journal of Urology, Apr 1, 2004

INTRODUCTION AND OBJECTIVE: Minimally invasive techniques, including laparoscopy and injection of... more INTRODUCTION AND OBJECTIVE: Minimally invasive techniques, including laparoscopy and injection of periureteral bulking agents, are intended to

Journal of Pediatric Surgery, 2007

Congenital midureteral stricture is an uncommon cause of prenatal hydronephrosis, and it is gener... more Congenital midureteral stricture is an uncommon cause of prenatal hydronephrosis, and it is generally associated with proximal hydroureteronephrosis [1,2]. We report a unique case of a congenital severe midureteral dilatation associated with mild proximal ureteral dilatation and normal distal ureteral diameter. The dilated midureter was excised, and an open end-to-end ureteroureterostomy was performed. Follow-up 6 months after surgical correction revealed marked improvement in the left-sided hydronephrosis and complete resolution of the hydroureter.

Fertility and Sterility, Mar 1, 2020

Globally, male factor infertility accounts for 20%-70% of couples struggling to conceive. Certain... more Globally, male factor infertility accounts for 20%-70% of couples struggling to conceive. Certain male pediatric developmental conditions, such as cryptorchidism, hypospadias, testicular and other childhood cancers, infections, and pediatric varicocele have been associated with future infertility. Early fertility preservation, especially in those with pending chemotherapy or genetic conditions such as Klinefelter syndrome, should be strongly considered in patients expected to experience testicular loss. Although optimal treatment timing may be unknown owing to a paucity of long-term prospective studies, early diagnosis and targeted treatment may optimize fertility potential in adulthood. (Fertil Steril Ò 2020;113:489-99. Ó2020 by American Society for Reproductive Medicine.

Frontiers in Pediatrics, Sep 4, 2017

Penile curvature is a frequent feature associated with hypospadias with also a great variability ... more Penile curvature is a frequent feature associated with hypospadias with also a great variability of severity among each patient. While the low-grade curvature (<30°) can be relatively easily corrected by simple techniques like penile degloving and dorsal plication, severe cases often demand more complex maneuvers to manage it. A great number of surgical techniques have been developed to adequately correct curvatures greater than 30°; however, each one of them should be individualized to different patients and local conditions encountered. In this article, we will review the evaluation of the pediatric patient with penile curvature associated with hypospadias with a special attention to high-grade cases, their management, indications for surgical treatment, and several surgical options for their definitive treatment.

The Journal of Urology, Apr 1, 2004

The Journal of Urology, Apr 1, 2005

THE JOURNAL OF UROLOGY® elevated levels of hydrostatic pressure. Average detrusor pressure for th... more THE JOURNAL OF UROLOGY® elevated levels of hydrostatic pressure. Average detrusor pressure for the control animals during the 24 hour period was 3.1 cm-H20 and average detrusor pressure for the obstructed animals during the 24 hour period was 19 cm-H20. In vivo experiments demonstrated a similar response in that both M2 and M3 expression were markedly up-regulated when compared to controls (3 and 8 fold, respectively). CONCLUSIONS: M2 and M3 receptors are up-regulated in a time and pressure dependent fashion after as little as 24 hours exposure to 20 cm-H20 hydrostatic pressure. These alterations in M receptors in the acute period may significantly influence bladder contractility and frequency of uninhibited contractions.

Videourology, Dec 1, 2022

WORLD SCIENTIFIC eBooks, Dec 1, 2010

Frontiers in Pediatrics, Mar 11, 2020

Journal of Pediatric Surgery, Apr 1, 2006

A 2-month-old child presented for evaluation of prenatal hydronephrosis. Imaging studies were con... more A 2-month-old child presented for evaluation of prenatal hydronephrosis. Imaging studies were consistent with a right duplex system with a dysplastic, nonfunctioning upper pole and lower pole ureteropelvic junction obstruction. We proceeded with removal of the upper pole and pyeloplasty and were surprised to find a single collecting system with a cystic, dysplastic upper pole segment and the absence of an upper pole pelvis or ureter. The rare diagnosis of a segmental multicystic dysplastic kidney with ipsilateral ureteropelvic junction obstruction was made. We present a review of the case and of previous literature on this topic.

International Braz J Urol, Dec 1, 2022

Introduction: Dismembered open pyeloplasty described by Anderson and Hynes is the "gold standard"... more Introduction: Dismembered open pyeloplasty described by Anderson and Hynes is the "gold standard" for the treatment of ureteropelvic junction obstruction. The aim of our study was to compare the results of open (OP) vs laparoscopic (LP) vs robotic (RALP) pyeloplasty. Material and Methods: A multicenter prospective review was conducted of pyeloplasty surgeries performed at five high-volume centers between 2014 and 2018. Demographic data, history of prenatal hydronephrosis, access type, MAG3 renogram and differential renal function, surgery time, length of hospital stay, and complication rate (Clavien-Dindo) were recorded. Access type was compared using the Kruskal-Wallis, Chi-square, or Fisher's exact tests. Results: A total of 322 patients were included: 62 OP, 86 LP, and 174 RALP. The mean age was 8.13 (r: 1-16) years, with a statistically significant lower age (mean 5 years) in OP (p < 0.001). There were no significant differences in the distribution of the side affected. Operative time was 110.5 min for OP, 140 min for LP, and 179 min for RALP (p < 0.0001). Hospital stay was significantly shorter in the RALP group than in the other groups (p < 0.0001). There were no differences in postoperative complications and reoperations between the three groups. Conclusions: Minimally invasive surgery for the management of UPJO in children is gaining more acceptance, even in patients younger than 1-year-old. Operative time continues to be significantly shorter in OP than in LP and RALP. Hospital stay was shorter in RALP compared to the other techniques. No differences were found in complication rates, type of complications, and reoperation rate.

Journal of Pediatric Urology

Annals of Vascular Surgery, Nov 1, 2011

NJ) is a cyanoacrylate-based synthetic surgical sealant. To date, the use of OMNEX has only been ... more NJ) is a cyanoacrylate-based synthetic surgical sealant. To date, the use of OMNEX has only been described in a limited number of vascular surgery procedures. We present the cases of two patients who underwent successful extracorporeal renal artery aneurysm repair with the aid of OMNEX sealant. This report is the first evidence to suggest the utility of OMNEX in renovascular surgery.

Journal of Urology

INTRODUCTION AND OBJECTIVE: Urethral duplication is a rare congenital condition in which there is... more INTRODUCTION AND OBJECTIVE: Urethral duplication is a rare congenital condition in which there is a complete or partial duplication of the urethra. As of 2016 there were less than 300 reported cases of this condition reported in the literature. This video sought to demonstrate the operative technique used to correct a Type 1B urethral duplication. METHODS: After informed consent was obtained photos and video footage were collected. RESULTS: This video includes epidimiologic information on urethral duplication, a patient presentation of Type 1B urethral duplication, and the surgical technique used to correct this. CONCLUSIONS: Urethral duplication is a rare congenital malformation that can be surgically corrected. The exact type of surgical correction is dependent on the type of duplication as well as any concomitant genitourinary abnormalities.

Journal of Urology, 2021

INTRODUCTION AND OBJECTIVE:In the last 4 decades, since the description of the appendix continent... more INTRODUCTION AND OBJECTIVE:In the last 4 decades, since the description of the appendix continent vesicostomy by Mitrofanoff, many variations have been described, including the Yang and Monti proce...

Urology case reports, Nov 1, 2018

Neurosurgery, Sep 1, 1999

Introduction: To determine risk factors for endoscopic third ven triculostomy (ETV) failure, Kapl... more Introduction: To determine risk factors for endoscopic third ven triculostomy (ETV) failure, Kaplan-Meier estimates of recurrence-free time were compared statistically with log rank test. Methods: Eighty-nine patients (52 new, 37 previously shunted) with obstructive hydrocephalus, who underwent ETV from 1994 to 1998, were reviewed. The factors analyzed were age, gender, etiology of hydrocephalus, location of CSF obstruction, presence of concurrent VP/VA shunts, history of shunt revisions or infections, preoperative symptoms, pre and postoperative imaging (ventricular size and CSF flow on cine MRI) and postoperative meningitis. Results: Twenty-nine patients (32.6%) required subsequent shunt ing and/or redo ETV. Among these 29 re-operations, 12 procedures (41.4%) were performed within 2 weeks, and only 3 greater than 18 months post-ETV. The ventricular size remained unchanged in 75% of cases the day following ETV, 48.2% at 6 months and 41.8% at 1 year. Seven complications (7.9%) occurred but were all transient. Risk of ETV failure increased with Chiari or Dandy-Walker malformations (relative risk 2.7, p =0.013), shunt infection at presentation (relative risk 2.9, p=0.0090), history of shunt infections (relative risk 6.2, p=0.0004), three or more previous shunt revisions (relative risk 4.6, p=0.0018) and postoperative meningitis (relative risk 4.1, p =0.0001). Late-onset idiopathic aqueductal stenosis is a significant predictor of good outcome (relative risk 0.40, p =0.044). Postoperative cine MRI can confirm ventriculostomy patency in 96.3% of patients with symp tom resolution. Conclusion: ETV can be performed safely with a low level of morbidity. The significant risk factors for failure are Chiari or Dandy-Walker malformations and intracerebral infections.

Urology, Jun 1, 2005

Augmentation cystoplasty operations using segments of gastrointestinal tract are often necessary ... more Augmentation cystoplasty operations using segments of gastrointestinal tract are often necessary in neurogenic low-compliance bladders. Patients are usually rehabilitated with an increase in storage volume and normalization of the reduced compliance. However, gut mucosa-related early and late complications are not very uncommon. Malignancy, although rare, is known to occur after enterocystoplasty, but only one such case has been reported for gastrocystoplasty, a single patient who developed urothelial carcinoma. We describe what we believe to be the first case of signet ring cell carcinoma developing after gastrocystoplasty.

The Journal of Urology, Apr 1, 2004

stable, but not resolved HUN at 8 years of followup, suffered significant asymptomatic worsening ... more stable, but not resolved HUN at 8 years of followup, suffered significant asymptomatic worsening in the degree of HUN and diminished renal function on one side and a renal stone on the contralateral renal unit at 14 year followup. CONCLUSIONS: Our long-term follow-up of children with antenatally diagnosed POM with mild to moderate pelviectasis confirms a high incidence of resolution and improvement. As we have documented I case of worsening of HUN at 14 year follow-up, we believe that ultrasonography should be periodically obtained until the child reaches adulthood at least in cases where complete resolution in HUN is not documented.

The Journal of Urology, Apr 1, 2004

INTRODUCTION AND OBJECTIVE: Minimally invasive techniques, including laparoscopy and injection of... more INTRODUCTION AND OBJECTIVE: Minimally invasive techniques, including laparoscopy and injection of periureteral bulking agents, are intended to

Journal of Pediatric Surgery, 2007

Congenital midureteral stricture is an uncommon cause of prenatal hydronephrosis, and it is gener... more Congenital midureteral stricture is an uncommon cause of prenatal hydronephrosis, and it is generally associated with proximal hydroureteronephrosis [1,2]. We report a unique case of a congenital severe midureteral dilatation associated with mild proximal ureteral dilatation and normal distal ureteral diameter. The dilated midureter was excised, and an open end-to-end ureteroureterostomy was performed. Follow-up 6 months after surgical correction revealed marked improvement in the left-sided hydronephrosis and complete resolution of the hydroureter.

Fertility and Sterility, Mar 1, 2020

Globally, male factor infertility accounts for 20%-70% of couples struggling to conceive. Certain... more Globally, male factor infertility accounts for 20%-70% of couples struggling to conceive. Certain male pediatric developmental conditions, such as cryptorchidism, hypospadias, testicular and other childhood cancers, infections, and pediatric varicocele have been associated with future infertility. Early fertility preservation, especially in those with pending chemotherapy or genetic conditions such as Klinefelter syndrome, should be strongly considered in patients expected to experience testicular loss. Although optimal treatment timing may be unknown owing to a paucity of long-term prospective studies, early diagnosis and targeted treatment may optimize fertility potential in adulthood. (Fertil Steril Ò 2020;113:489-99. Ó2020 by American Society for Reproductive Medicine.

Frontiers in Pediatrics, Sep 4, 2017

Penile curvature is a frequent feature associated with hypospadias with also a great variability ... more Penile curvature is a frequent feature associated with hypospadias with also a great variability of severity among each patient. While the low-grade curvature (<30°) can be relatively easily corrected by simple techniques like penile degloving and dorsal plication, severe cases often demand more complex maneuvers to manage it. A great number of surgical techniques have been developed to adequately correct curvatures greater than 30°; however, each one of them should be individualized to different patients and local conditions encountered. In this article, we will review the evaluation of the pediatric patient with penile curvature associated with hypospadias with a special attention to high-grade cases, their management, indications for surgical treatment, and several surgical options for their definitive treatment.

The Journal of Urology, Apr 1, 2004

The Journal of Urology, Apr 1, 2005

THE JOURNAL OF UROLOGY® elevated levels of hydrostatic pressure. Average detrusor pressure for th... more THE JOURNAL OF UROLOGY® elevated levels of hydrostatic pressure. Average detrusor pressure for the control animals during the 24 hour period was 3.1 cm-H20 and average detrusor pressure for the obstructed animals during the 24 hour period was 19 cm-H20. In vivo experiments demonstrated a similar response in that both M2 and M3 expression were markedly up-regulated when compared to controls (3 and 8 fold, respectively). CONCLUSIONS: M2 and M3 receptors are up-regulated in a time and pressure dependent fashion after as little as 24 hours exposure to 20 cm-H20 hydrostatic pressure. These alterations in M receptors in the acute period may significantly influence bladder contractility and frequency of uninhibited contractions.

Videourology, Dec 1, 2022

WORLD SCIENTIFIC eBooks, Dec 1, 2010

Frontiers in Pediatrics, Mar 11, 2020

Journal of Pediatric Surgery, Apr 1, 2006

A 2-month-old child presented for evaluation of prenatal hydronephrosis. Imaging studies were con... more A 2-month-old child presented for evaluation of prenatal hydronephrosis. Imaging studies were consistent with a right duplex system with a dysplastic, nonfunctioning upper pole and lower pole ureteropelvic junction obstruction. We proceeded with removal of the upper pole and pyeloplasty and were surprised to find a single collecting system with a cystic, dysplastic upper pole segment and the absence of an upper pole pelvis or ureter. The rare diagnosis of a segmental multicystic dysplastic kidney with ipsilateral ureteropelvic junction obstruction was made. We present a review of the case and of previous literature on this topic.

International Braz J Urol, Dec 1, 2022

Introduction: Dismembered open pyeloplasty described by Anderson and Hynes is the "gold standard"... more Introduction: Dismembered open pyeloplasty described by Anderson and Hynes is the "gold standard" for the treatment of ureteropelvic junction obstruction. The aim of our study was to compare the results of open (OP) vs laparoscopic (LP) vs robotic (RALP) pyeloplasty. Material and Methods: A multicenter prospective review was conducted of pyeloplasty surgeries performed at five high-volume centers between 2014 and 2018. Demographic data, history of prenatal hydronephrosis, access type, MAG3 renogram and differential renal function, surgery time, length of hospital stay, and complication rate (Clavien-Dindo) were recorded. Access type was compared using the Kruskal-Wallis, Chi-square, or Fisher's exact tests. Results: A total of 322 patients were included: 62 OP, 86 LP, and 174 RALP. The mean age was 8.13 (r: 1-16) years, with a statistically significant lower age (mean 5 years) in OP (p < 0.001). There were no significant differences in the distribution of the side affected. Operative time was 110.5 min for OP, 140 min for LP, and 179 min for RALP (p < 0.0001). Hospital stay was significantly shorter in the RALP group than in the other groups (p < 0.0001). There were no differences in postoperative complications and reoperations between the three groups. Conclusions: Minimally invasive surgery for the management of UPJO in children is gaining more acceptance, even in patients younger than 1-year-old. Operative time continues to be significantly shorter in OP than in LP and RALP. Hospital stay was shorter in RALP compared to the other techniques. No differences were found in complication rates, type of complications, and reoperation rate.

Journal of Pediatric Urology

Annals of Vascular Surgery, Nov 1, 2011

NJ) is a cyanoacrylate-based synthetic surgical sealant. To date, the use of OMNEX has only been ... more NJ) is a cyanoacrylate-based synthetic surgical sealant. To date, the use of OMNEX has only been described in a limited number of vascular surgery procedures. We present the cases of two patients who underwent successful extracorporeal renal artery aneurysm repair with the aid of OMNEX sealant. This report is the first evidence to suggest the utility of OMNEX in renovascular surgery.

Journal of Urology

INTRODUCTION AND OBJECTIVE: Urethral duplication is a rare congenital condition in which there is... more INTRODUCTION AND OBJECTIVE: Urethral duplication is a rare congenital condition in which there is a complete or partial duplication of the urethra. As of 2016 there were less than 300 reported cases of this condition reported in the literature. This video sought to demonstrate the operative technique used to correct a Type 1B urethral duplication. METHODS: After informed consent was obtained photos and video footage were collected. RESULTS: This video includes epidimiologic information on urethral duplication, a patient presentation of Type 1B urethral duplication, and the surgical technique used to correct this. CONCLUSIONS: Urethral duplication is a rare congenital malformation that can be surgically corrected. The exact type of surgical correction is dependent on the type of duplication as well as any concomitant genitourinary abnormalities.

Journal of Urology, 2021

INTRODUCTION AND OBJECTIVE:In the last 4 decades, since the description of the appendix continent... more INTRODUCTION AND OBJECTIVE:In the last 4 decades, since the description of the appendix continent vesicostomy by Mitrofanoff, many variations have been described, including the Yang and Monti proce...