Open versus robot-assisted laparoscopic ureteral reimplantation: Hospital charges analysis and outcomes at a single institution.

PURPOSE: Robot-assisted laparoscopic extravesical ureteral reimplantation has previously been described as a viable minimally invasive option to open surgery. However, concerns for robotic surgery have been raised owing to assumed higher costs and heterogeneous clinical outcomes. We hypothesized that similar hospital charges and clinical outcomes occur when comparing open and robotic cases in matched cohorts. MATERIALS AND METHODS: Open and robotic reimplantation cases from 2013 to 2015 for primary vesicoureteral reflux were matched by age using 1:1 nearest neighbor matching. The matched cohorts were analyzed and compared for their direct itemized hospital charges per surgical case, complications, and clinical outcomes. RESULTS: There were 38 patients in each group after age-matching the 135 patients. Operating room charges were higher for the robotic group compared to the open group (p=0.002), whereas pharmacy and laboratory costs were lower for the robotic group. However, there were no significant differences in total overall charges between the open and robotic groups with cystoscopy or without cystoscopy (p=0.345, p=0.533), since the median hospital stay length was shorter for the robotic group (p<0.001). Clinical success rates were identical for the two groups (open 94.8% vs robotic 94.8%). There were also no significant differences in number of complications between the two cohorts. CONCLUSIONS: This is the first age-matched study comparing hospital charges and clinical outcomes of pediatric open and robotic reimplantation. While operating room charges were higher for the robotic cohort, lower hospitalization charges led to comparable overall hospital charges, as well as equivalent clinical outcomes for both cohorts. LEVEL OF STUDY: Level III (Retrospective comparative study) TYPE OF STUDY: Retrospective Study.

Novel prognostic grayscale ultrasonographic findings in the testis from a comprehensive analysis of pediatric patients with testicular torsion.

INTRODUCTION: Although grayscale and Doppler ultrasound (US) findings of testicular torsion (TT) have previously been described in the literature, other US findings may provide more prognostic information to families. OBJECTIVE: The authors hypothesized that a comprehensive analysis of US findings of TT that focused on time-dependent changes would lead to additional ultrasonographic morphologic findings and clinically relevant prognostic information. STUDY DESIGN: The authors reviewed the records of pediatric patients with acute TT from 2010 to 2017. The sizes and parenchymal characteristics of the torsed and contralateral testes on US were analyzed in relation to the time duration from the onset of scrotal pain to the time of surgery (0-6 h, 6-12 h, 12-24 h, 24-48 h, and >48 h), torsion degree, and clinical outcomes of the testes. RESULTS: Patient demographics, time intervals, and US measurements of the torsed and contralateral testes showed significant differences with respect to testicular viability (Summary Table). The mean volume ratios of torsed to contralateral testis showed significant differences between the 0-6 h and the 12-24 h time groups as well as the 6-12 h and the 12-24 h time groups (P = 0.003 and P = 0.035, respectively), as well as significant differences between the viable and non-viable testes (P = 0.005). Regarding testicular heterogeneity, two novel grayscale sonographic findings were noted: (1) multiple hypoechoic lines that were termed 'testicular fragmentation' and (2) hyperechoic patches that were termed 'testicular patching'. The presence of these two findings were significantly increased as TT time duration increased (P < 0.001), and these findings were significantly associated with testicular non-viability (P < 0.001). Torsion degree was also noted to be significantly higher in the non-viable testes (P < 0.001). Presence of hydrocele or scrotal edema also showed significant differences between the TT time groups (P < 0.001). DISCUSSION: The results of this study demonstrated ultrasonographic findings related to time dependent changes in TT and provided prognostic information regarding testicular viability. CONCLUSIONS: Specific US grayscale findings in torsed testes (testicular fragmentation and testicular patching) were identified that provide prognostic information regarding time duration of testicular torsion and testicular viability. Testicular fragmentation and testicular patching significantly increased as TT time increased, with increasing risk for testicular non-viability.

Does de novo hydronephrosis after pediatric robot-assisted laparoscopic ureteral re-implantation behave similarly to open re-implantation?

BACKGROUND: While open ureteral re-implantation surgery is the gold standard for surgical correction of vesicoureteral reflux (VUR), robot-assisted laparoscopic ureteral re-implantation via an extravesical approach (RALUR-EV) has become a minimally invasive alternative. Previous studies have shown that transient hydronephrosis after open re-implantation can occur in up to 28% of patients. However, previous studies have also shown that de novo hydronephrosis after open re-implantation is not predictive of final differential renal function. OBJECTIVE: A retrospective review was performed to characterize the natural history of postoperative hydronephrosis after RALUR-EV for primary VUR in pediatric patients. STUDY DESIGN: A retrospective chart review of a single-surgeon series was performed for pediatric patients who underwent RALUR-EV for primary VUR. The severity of de novo hydronephrosis was assessed using the Society for Fetal Urology (SFU) grading system via renal ultrasound at the 1-month postoperative follow-up. Renal ultrasound was performed at least every six months. Radiographic success was defined as complete resolution of VUR on the voiding cystourethrogram at the 4-month mark. Patient demographics, surgery duration, length of hospital stay, pre-operative and postoperative VUR grades, and follow-up time periods were collected. Patients with other associated urinary pathology and patients lost to follow-up were excluded from the study. RESULTS: A total of 87 patients (121 kidney units) with primary VUR who underwent RALUR-EV met the inclusion criteria. SFU grade 1-3 hydronephrosis was noted in 30.3% (36/119) of kidney units at the 1-month mark, but 83.9% (26/31) cases with hydronephrosis completely resolved in a median time of 7.9 months (range: 3.4-21.0 months), and all four cases with unresolved hydronephrosis were downgraded to SFU grade 1 without the need for intervention. DISCUSSION: A radiographic success rate of 96% was demonstrated in this cohort, which is comparable with that of historical open re-implantation series. A similar rate of de novo hydronephrosis was also noted in this cohort when compared with that of previous open re-implantation series, but de novo hydronephrosis after RALUR-EV had a similar or more rapid resolution rate than that previously reported after open intravesical and extravesical re-implantation series. CONCLUSION: De novo hydronephrosis after RALUR-EV behaves similarly to de novo hydronephrosis after open ureteral re-implantation, where de novo hydronephrosis is present in up to 30% of pediatric patients who underwent RALUR-EV. The hydronephrosis self-resolves without the need for intervention in the overwhelming majority of cases and resolves at a median time of 7.9 months after surgery.

Surgical interventions and anesthesia in the 1st year of life for lower urinary tract obstruction.

BACKGROUND: Patients with a prenatal diagnosis of lower urinary tract obstruction (LUTO) may undergo prenatal interventions, such as vesicoamniotic shunt (VAS) placement, as a temporary solution for relieving urinary tract obstruction. A recent FDA communication has raised awareness of the potential neurocognitive adverse effects of anesthesia in children. We hypothesized as to whether a prenatal LUTO staging system was predictive of the number of anesthesia events for prenatally diagnosed LUTO patients. METHODS: We retrospectively reviewed the prenatal and postnatal clinical records for patients with prenatally diagnosed LUTO from 2012 to 2015. Patients were stratified by prenatal VAS status and by LUTO disease severity according to Ruano et al. (Ultrasound Obstet Gynecol. 2016). RESULTS: 31 patients were identified with a prenatal LUTO diagnosis, and postnatal records were available for 21 patients (seven patients in each stage). When combining prenatal and postnatal anesthesia, there was a significant difference in the number of anesthesia encounters by stage (1.6, 3.7, and 6.7 for Stage I, II, and III respectively, p = .034). Upon univariate analysis, higher gestational age (GA) at birth was associated with a decreased number of anesthesia events in the first year (p = .031). CONCLUSIONS: The majority of infants with prenatally diagnosed LUTO will undergo postnatal procedures with general anesthesia exposure in the first year of life. Patients with higher prenatal LUTO severity experienced a higher number of both prenatal and postnatal anesthesia encounters. In addition, higher GA at birth was associated with fewer anesthesia encounters in the first year. LEVEL OF EVIDENCE: This is a prognostic study with Level IV evidence.

Does the use of 5 mm instruments affect the outcomes of robot-assisted laparoscopic pyeloplasty in smaller working spaces? A comparative analysis of infants and older children.

INTRODUCTION: Pediatric robot-assisted laparoscopic (RAL) pyeloplasty has become a viable minimally invasive surgical option for ureteropelvic junction obstruction (UPJO) based on its efficacy and safety. However, RAL pyeloplasty in infants can be a challenging procedure because of the smaller working spaces. The use of the larger 8 mm instruments for these patients instead of the 5 mm instruments is common because of the shorter wrist lengths. OBJECTIVE: We hypothesized that the use of 5 mm instruments for RAL pyeloplasty in infants with smaller working spaces will have comparable perioperative parameters and surgical outcomes in comparison with older children with larger working spaces. STUDY DESIGN: We compared the perioperative parameters and surgical outcomes of RAL pyeloplasties performed by a single surgeon in infants and non-infant pediatric patients over a 2 year period. All of the procedures were performed using an 8.5 mm camera and 5 mm robotic instruments. Patient demographics, operative times, perioperative complications, hospital pain medication usage, hospital length of stay, and treatment success rates were compared between the two groups. RESULTS: A total of 65 pediatric RAL pyeloplasties were included in the study (16 infants and 49 non-infants, Table). There were no significant differences in gender, laterality, proportion of re-do pyeloplasty, or preoperative hydronephrosis grade between the two groups. All procedures were performed without conversion to open surgery or significant perioperative complications. There were no differences in segmental operative times (total operative time, console time, port placement time, time for dissection to UPJO, and anastomosis time), hospital pain medication usage, and hospital length of stay between the two groups (p > 0.05 for all comparisons). The treatment success rates were 93.8% (15/16) and 100% (49/49), respectively (p = 0.08). DISCUSSION: We present the first comparative study of infant and non-infant pediatric RAL pyeloplasty using 5 mm robotic instruments. An advantage of the current study is the use of a single surgeon's experience to compare RAL pyeloplasty outcomes in infants with those of older children, a group in which RAL pyeloplasty has already been shown to be efficacious and safe. Operative tips for infant RAL pyeloplasty are also provided. CONCLUSIONS: RAL pyeloplasty is a safe and effective surgical modality even in infants, with comparable perioperative parameters and outcomes as those in older children. The use of 5 mm instruments in infants does not affect outcomes and offers the potential for improved cosmesis.

Multi-Institution Case Series of Pediatric Patients with Laparoscopic Repair of Morgagni Hernia.

INTRODUCTION: Morgagni Larray hernia (MLH) is a very rare disease, which accounts for less than 5% of all congenital diaphragmatic hernias. Laparoscopic repair has been widely used and accepted as a treatment option for patients with this disease. The purpose of our study is to analyze the outcomes of patients with MLH who underwent laparoscopic repair, and to evaluate their postoperative course for outcome, morbidity, and mortality. MATERIALS AND METHODS: A retrospective chart review was performed of patients who were diagnosed with MLH and treated laparoscopically by 10 board-certified pediatric surgeons. RESULTS: Fourteen patients were included in the study. One patient died 1 month postoperatively due to respiratory complications unrelated to the surgery. Thirteen patients were followed for a median of 1.75 years (interquartile 0.3-6.95). There was a single recurrence, which resulted in a partial resection of the hernia sac and repaired without a mesh. We had a success rate of 92.86%. CONCLUSION: MLH is a rare congenital diaphragmatic hernia that is usually diagnosed incidentally. Laparoscopic repair has high success rates and is a viable option for patients with this pathology.

Quantifying the Additional Difficulty of Pediatric Robot-Assisted Laparoscopic Re-Do Pyeloplasty: A Comparison of Primary and Re-Do Procedures.

BACKGROUND: Re-do pyeloplasty after failed open or laparoscopic ureteropelvic junction (UPJ) obstruction correction can be a challenging procedure because of scar formation at the previous anastomosis site and decreased vascularity of the ureter. This study compared the perioperative parameters for pediatric robot-assisted laparoscopic (RAL) primary and re-do pyeloplasties with an emphasis on the intra-operative parameters. MATERIALS AND METHODS: We compared the perioperative parameters of pediatric RAL procedures performed by a single surgeon at a tertiary care children's hospital for both primary ureteropelvic junction obstruction (UPJO) and recurrent UPJO after a previous open or laparoscopic procedure over 2013-2015. The operative time was subdivided as total operative time, console time, port placement time, dissection time to UPJ, and anastomosis time. RESULTS: A total of 65 pediatric RAL pyeloplasty procedures for UPJO were performed (55 primary and 10 re-do pyeloplasties) during the study period. The console times were 43.3% longer for re-do pyeloplasties than for primary pyeloplasties (133.0 ± 30.7 versus 92.8 ± 24.0 minutes, respectively, P < .01). The re-do cases had longer operative times, especially for UPJ exposure (52.2 ± 21.0 versus 28.0 ± 14.0 minutes, P < .01). There were no conversions to open surgery or significant perioperative complications. There was no difference in hospital pain medication usage and hospital length of stay between the 2 groups. The treatment success rates were 98.2% (54/55) and 100% (10/10), respectively. CONCLUSIONS: RAL re-do pyeloplasty is associated with significantly longer operative times as compared with primary pyeloplasties, especially during the exposure of the UPJ, but it is overall a safe and effective surgical modality for persistent/recurrent UPJO in children. As surgeons are increasingly asked for more accurate predictions of operative time lengths when scheduling cases, this information can be helpful for surgeons when scheduling these cases and with counseling families.

Pediatric medical device development by surgeons via capstone engineering design programs.

BACKGROUND: There is a need for pediatric medical devices that accommodate the unique physiology and anatomy of pediatric patients that is increasingly receiving more attention. However, there is limited literature on the programs within children's hospitals and academia that can support pediatric device development. We describe our experience with pediatric device design utilizing collaborations between a children's hospital and two engineering schools. METHODS: Utilizing the academic year as a timeline, unmet pediatric device needs were identified by surgical faculty and matched with an engineering mentor and a team of students within the Capstone Engineering Design programs at two universities. The final prototypes were showcased at the end of the academic year and if appropriate, provisional patent applications were filed. RESULTS: All twelve teams successfully developed device prototypes, and five teams obtained provisional patents. The prototypes that obtained provisional patents included a non-operative ureteral stent removal system, an evacuation device for small kidney stone fragments, a mechanical leech, an anchoring system of the chorio-amniotic membranes during fetal surgery, and a fetal oxygenation monitor during fetoscopic procedures. CONCLUSIONS: Capstone Engineering Design programs in partnership with surgical faculty at children's hospitals can play an effective role in the prototype development of novel pediatric medical devices. LEVELS OF EVIDENCE: N/A - No clinical subjects or human testing was performed.

Protocol for a prospective observational study of cortical lower urinary tract control changes following intradetrusor injection of botulinum toxin-A in patients with multiple sclerosis.

INTRODUCTION: Multiple sclerosis (MS) is a severe debilitating disease that affects patients' quality of life. Up to 90% of patients with MS will develop lower urinary tract dysfunction within the first 18 years of the disease. If oral pharmacotherapy with anticholinergics, behavioural modifications and pelvic floor physical therapy are unsuccessful, intradetrusor injection of botulinum toxin-A (OnaBotA; Botox Allergan, Dublin, Ireland) is a highly effective option for these patients. The local effects of OnaBotA are well understood, but not much is known of its afferent/sensory effects while treating the end organ. Our study will use functional MRI (fMRI) and task-related blood oxygen level-dependent signals to evaluate patients with MS and neurogenic detrusor overactivity (NDO) prior to, and after, intradetrusor injection of OnaBotA with simultaneous urodynamic evaluation. Urinary concentration of brain-derived neurotrophic factor and nerve growth factor will also be collected since it has been shown that patients with an overactive bladder have higher concentrations of these neuropeptides. METHODS AND ANALYSIS: Female patients with MS and lower urinary tract symptoms who previously have undergone urodynamic screening and are refractory to conservative and oral pharmacotherapy management for NDO and are interested in OnaBotA intradetrusor injection will be invited to participate in the study. An fMRI will be performed preintradetrusor injection and postintradetrusor injection of OnaBotA with simultaneous MRI compatible with material urodynamics. Images will be collected and analysed accordingly. ETHICS AND DISSEMINATION: All of the patients are properly consented before enrolling in this study that has been previously approved by the Institutional Review Board. Results of neural connectivity activation will be presented at national and international meetings and published in scholarly journals.

Surgeon Burnout among American Pediatric Urologists.

INTRODUCTION: Burnout is a syndrome characterized by exhaustion, depersonalization and low personal achievement that leads to decreased effectiveness at work. Little to no information is known about the surgeon burnout rate of pediatric urologists. METHODS: An online survey containing a modified Maslach Burnout Inventory and additional demographic information was emailed to practicing pediatric urologists in the United States. The dependent variable was professional burnout measured by 3 subscales from the Maslach Burnout Inventory of 1) emotional exhaustion, 2) depersonalization and 3) low personal achievement. The independent variables included surgeon demographics and practice characteristics. RESULTS: The survey response rate was 66.7%. Of the 41 subjects most were male (82.9%), approximately three-quarters worked at academic centers, more than half had a rank of division chief or full professor and more than half worked more than 60 hours per week. Six (14.6%) pediatric urologists met the criteria for burnout, defined as high scores in emotional exhaustion plus high scores in depersonalization or low personal achievement. When comparing demographic and practice characteristics between pediatric urologists who were burned out to those who were not burned out, there were no statistically significant differences between the 2 groups. Only American Urological Association North Central and Western sections had surgeons with burnout. CONCLUSIONS: Pediatric urologists have a low burnout rate compared to adult urologists and other surgical specialties.

Urologic Considerations in the Separation of Thoracoomphalopagus Conjoined Twins.

Conjoined twins are seen in approximately 1/500,000 live births, and therefore surgical management of urologic anomalies in conjoined twins has not been extensively reported. Various degrees of sharing of the urinary tracts and genitalia can be seen in different types of conjoined twins. Detailed preoperative imaging, including magnetic resonance imaging, computed tomography, and voiding cystourethrogram, is essential to define the anatomy and planning of a successful separation. We describe the urologic presentation, evaluation, and treatment of thoracoomphalopagus conjoined twins.

Urologic Outcomes of Children With Hemorrhagic Cystitis After Bone Marrow Transplant at a Single Institution.

OBJECTIVE: To analyze clinical outcomes and the risk factors associated with genitourinary (GU) morbidity and mortality in children who present with hemorrhagic cystitis (HC) after bone marrow transplant (BMT). METHODS: A retrospective chart review of patients with HC who had undergone BMT at a single pediatric hospital from 2008 to 2015 was conducted. Demographic data, severity of hematuria, HC management, and mortality were analyzed. Bivariate analysis and binary logistic regression were performed to identify risk factors. RESULTS: Out of 43 patients who met inclusion criteria, 67.4% were male with a median age at BMT of 10.2 years (interquartile range 5.8-14.6). Percutaneous nephrostomy catheters were inserted in 5 patients for urinary diversion. All-cause mortality was 32.6% (N = 14). Intravesical retroviral therapy (P <.001), HC grade (P <.001), total Foley time (P <.001), total gross hematuria time (P <.001), total days hospitalized (P = .012), and days to most improved hematuria (P = .032) were associated with significant GU morbidity on bivariate analysis. On multivariable analysis, days to most improved hematuria was associated with significant GU morbidity odds ratio of 1.177 (1.006-1.376) (P = .042). Status of percutaneous nephrostomy was not associated with increased mortality (P = .472); however, in the multivariate model, BK viremia (P = .023), need for renal dialysis (P = .003), and presence of Foley catheter (P = .005) were associated with increased mortality. CONCLUSION: Children with HC after BMT fall in a very high-risk category with high mortality and significant GU morbidity. The presence of a Foley catheter, need for dialysis, and BK viremia are associated with increased mortality.

Erratum: Thoracoscopic Patch Repair of Congenital Diaphragmatic Hernia in a Neonate Using Spiral Tacks: A Case Report.

[This corrects the article on p. 31 in vol. 4, PMID: 26290813.].

Vacuum-assisted Closure of a Vesicocutaneous Fistula in a Pediatric Patient After Bladder Cystoplasty.

A vesicocutaneous fistula is an abnormal communication from the bladder to the skin (Pritts et al, 2001). Recently, wound vacuum-assisted closure (VAC) has been used to facilitate fistula closure. There are no reports of using VAC to help fistula closure in the pediatric population. We present a case of an adolescent patient who develops a vesicocutaneous fistula after bladder augment cystoplasty and was treated with VAC only.

Vitamin D in Tear Fluid.

PURPOSE: To determine the source(s) of vitamin D in tear fluid and examine the expression of the endocytic proteins and putative vitamin D transporters megalin and cubilin in lacrimal and Harderian glands. METHODS: Wild-type, heterozygous, and vitamin D receptor (VDR) knockout C57BL/6 mice were used, with a subset of knockout mice fed a replenishment diet for some studies. Mouse lacrimal and Harderian glands from each group were used to measure megalin and cubilin by RT-PCR, Western blot, and immunohistochemistry. New Zealand white rabbits were used to collect lacrimal and accessory gland fluid for vitamin D mass spectroscopy measurements. RESULTS: Ten-week-old knockout mice were significantly (P < 0.05) smaller than wild-type mice. Real-time PCR and Western blot showed decreased expression of megalin and cubilin in select VDR knockout mouse groups. Immunohistochemistry showed apical duct cell megalin staining and weaker megalin staining in VDR knockout mice compared with controls. Vitamin D2 was more prevalent in rabbit lacrimal and accessory gland fluid than vitamin D3, and greater amounts of Vitamin D2 were found in in tear fluid obtained directly from lacrimal and accessory glands as compared with plasma concentrations. CONCLUSIONS: This is the first study to demonstrate the presence of megalin and cubilin in lacrimal and accessory glands responsible for producing tear fluid. The results strengthen the hypothesis that megalin and cubilin are likely involved in the secretory pathway of vitamin D into tear fluid by the duct cells.

Thoracoscopic Patch Repair of Congenital Diaphragmatic Hernia in a Neonate using Spiral Tacks: A Case Report.

We present a case of congenital diaphragmatic hernia that was successfully treated with spi-ral tacks using thoracoscopy. A newborn female was diagnosed with a diaphragmatic hernia at 20 weeks of gestation. The defect was surgically repaired by thoracoscopy and primary closure. On postoperative day 25, she developed respiratory distress. Chest x-ray showed a recurrence and was taken to the OR for surgical repair with spiral tacks.

Palpable Undescended Testes: 15 Years of Experience and Outcome in Laparoscopic Orchiopexy.

BACKGROUND AND PURPOSE: Most of the current literature concerning laparoscopy in patients with cryptorchidism reports on those with nonpalpable testes. The purpose of this study is to share our experience and outcome in laparoscopic orchiopexy on patients with palpable undescended testes. PATIENTS AND METHODS: From January 1999 to July 2014, 240 cryptorchid testes were treated of which 192 (155 patients) were palpable and were operated on by laparoscopy. Before starting, the bladder is emptied with a Foley catheter. Four trocars are used: One 5 mm for the lens (45 degree), one 10 mm (transscrotal), and two 3 mm placed at the subcostal midclavicular line for the instruments. We localize the deep inguinal ring and open the peritoneum. The spermatic vessels and vas deferens are dissected in a cephalic direction. The epigastric vessels are dissected and sectioned to facilitate the localization of the testicle inside the canal. Once found, the testis is dissected and taken into the abdominal cavity where the gubernaculum testis is cut. A 10-mm trocar is introduced through the scrotal sac into the peritoneal cavity. The testicle is grabbed and pulled down to the scrotum where it will be fixed with a 5-0 polypropylene suture in the usual manner. RESULTS: Of 192 cryptorchid palpable testes treated with laparoscopy, only one procedure was converted to conventional open orchiopexy because of an ectopic testicle (above the aponeurosis of the oblique muscle). The rest of the testicles could be moved down to the scrotal sac. Our follow-up ranges from 6 months to 15 years, and we have not found atrophy in any of the testicles. To date, only two (0.4%) testicles have reascended. CONCLUSION: Laparoscopy is a great and safe option for patients with palpable undescended testes, regardless of its position in the inguinal canal.

Effect of vitamin D receptor knockout on cornea epithelium wound healing and tight junctions.

PURPOSE: Our laboratory previously determined that vitamin D3, the vitamin D receptor (VDR), and 1α hydroxylase are present and active in the eye. In this study, we examined the effects of VDR knockout on wound healing, the tight junction-associated proteins occludin and ZO-1, and tight junction numbers in mouse corneas. METHODS: Epithelial wounds (2-mm) were made with an agar brush on 4-week-old and 10-week-old wild-type, heterozygous, and VDR knockout mouse corneas. Mice were on a normal or high lactose, Ca(2+), and PO4(-) diet. Wound-healing area was measured over time. Real-time PCR was used to quantify occludin and ZO-1 message expression. Western blot was used for protein expression. Transmission electron microscopy was used to examine corneal epithelium and endothelium tight junctions. Immunofluorescence was used to examine epithelial ZO-1 distribution. RESULTS: Results showed a decreased healing rate in 10-week-old VDR knockout mice compared with wild-types. Vitamin D receptor knockout mice on the special diet had no difference in healing rate compared with wild-types. Real-time PCR showed decreased expression of occludin and ZO-1 in 10-week-old VDR knockout mice compared with wild-types. Western blot of 10-week-old knockout mouse corneas showed decreased occludin expression compared with wild-types. Transmission electron microscopy showed a significant difference in tight junction numbers in VDR knockouts versus wild-types. Immunofluorescence showed a change in ZO-1 distribution among genotypes. CONCLUSIONS: Vitamin D receptor knockout affects mouse corneal epithelium wound healing and tight junction integrity.

Effect of Surgical Technique on Corneal Implant Performance.

PURPOSE: Our aim was to determine the effect of a surgical technique on biomaterial implant performance, specifically graft retention. METHODS: Twelve mini pigs were implanted with cell-free, 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC)/N-hydroxysuccinimide (NHS) cross-linked recombinant human collagen type III (RHCIII) hydrogels as substitutes for donor corneal allografts using overlying sutures with or without human amniotic membrane (HAM) versus interrupted sutures with HAM. The effects of the retention method were compared as well as the effects of collagen concentration (13.7% to 15% RHCIII). RESULTS: All implanted corneas showed initial haze that cleared with time, resulting in corneas with optical clarity matching those of untreated controls. Biochemical analysis showed that by 12 months post operation, the initial RHCIII implants had been completely remodeled, as type I collagen, was the major collagenous protein detected, whereas no RHCIII could be detected. Histological analysis showed all implanted corneas exhibited regeneration of epithelial and stromal layers as well as nerves, along with touch sensitivity and tear production. Most neovascularization was seen in corneas stabilized by interrupted sutures. CONCLUSIONS: This showed that the surgical technique used does have a significant effect on the overall performance of corneal implants, overlying sutures caused less vascularization than interrupted sutures. TRANSLATIONAL RELEVANCE: Understanding the significance of the suturing technique can aid the selection of the most appropriate procedure when implanting artificial corneal substitutes. The same degree of regeneration, despite a higher collagen content indicates that future material development can progress toward stronger, more resistant implants.