Mechanosensitive hair cell-like cells from embryonic and induced pluripotent stem cells.

Mechanosensitive sensory hair cells are the linchpin of our senses of hearing and balance. The inability of the mammalian inner ear to regenerate lost hair cells is the major reason for the permanence of hearing loss and certain balance disorders. Here, we present a stepwise guidance protocol starting with mouse embryonic stem and induced pluripotent stem cells, which were directed toward becoming ectoderm capable of responding to otic-inducing growth factors. The resulting otic progenitor cells were subjected to varying differentiation conditions, one of which promoted the organization of the cells into epithelial clusters displaying hair cell-like cells with stereociliary bundles. Bundle-bearing cells in these clusters responded to mechanical stimulation with currents that were reminiscent of immature hair cell transduction currents.

Single-cell RNA sequencing of intestinal immune cells in neonatal necrotizing enterocolitis.

PURPOSE: Necrotizing enterocolitis (NEC) causes fatal intestinal necrosis in neonates, but its etiology is unknown. We analyzed the intestinal immune response to NEC. METHODS: Using single-cell RNA sequencing (scRNA-seq), we analyzed the gene expression profiles of intestinal immune cells from four neonates with intestinal perforation (two with NEC and two without NEC). Target mononuclear cells were extracted from the lamina propria of the resected intestines. RESULTS: In all four cases, major immune cells, such as T cells (15.1-47.7%), B cells (3.1-19.0%), monocytes (16.5-31.2%), macrophages (1.6-17.4%), dendritic cells (2.4-12.2%), and natural killer cells (7.5-12.8%), were present in similar proportions to those in the neonatal cord blood. Gene set enrichment analysis showed that the MTOR, TNF-α, and MYC signaling pathways were enriched in T cells of the NEC patients, suggesting upregulated immune responses related to inflammation and cell proliferation. In addition, all four cases exhibited a bias toward cell-mediated inflammation, based on the predominance of T helper 1 cells. CONCLUSION: Intestinal immunity in NEC subjects exhibited stronger inflammatory responses compared to non-NEC subjects. Further scRNA-seq and cellular analysis may improve our understanding of the pathogenesis of NEC.

Risk factors and outcomes of bile leak after laparoscopic surgery for congenital biliary dilatation.

PURPOSE: One of the main causes of stricture at hepaticojejunostomy site after surgery for congenital biliary dilatation is inflammation or infection associated with bile leak. The aim of this study was to determine the risk factors and outcomes of bile leak after laparoscopic surgery. METHODS: We retrospectively reviewed the demographics and outcomes of patients who underwent laparoscopic surgery for congenital biliary dilatation between September 2013 and December 2019. Data from patients with bile leak were compared to data from patients without bile leak. RESULTS: Fourteen of 78 patients had bile leak. Hepatic duct diameter at anastomosis was the only risk factor of bile leak. Patients with the diameter ≤ 10 mm had higher incidence of bile leak than in patients with the diameter > 10 mm (P = 0.0023). Among them, bile leak occurred more frequently in patients operated on by non-qualified surgeons based on the Japan Society for Endoscopic Surgery endoscopic surgical skill qualification system than by qualified surgeons (P = 0.027). However, none of the patients with bile leak developed anastomotic stricture afterwards. CONCLUSION: Although good technical skill is necessary to avoid bile leak in narrow hepatic duct cases (≤ 10 mm), slight bile leak may not result in anastomotic stricture.

Laparoscopic Kasai portoenterostomy is advantageous over open Kasai portoenterostomy in subsequent liver transplantation.

BACKGROUND: Native liver survival after laparoscopic Kasai portoenterostomy (Lap-PE) for biliary atresia (BA) is controversial. We examined whether a jaundice-free native liver survival rate is comparable between conventional Kasai portoenterostomy (Open-PE) and Lap-PE. Then, the impact of the two types of PE on subsequent living-donor liver transplantation (LTx) was addressed in this study. METHODS: The jaundice-free rate in 1- and 2-year-old patients who underwent Open-PE and Lap-PE from January 2006 to December 2017 was investigated. Additionally, perioperative data (duration from the start of surgery to the completion of hepatectomy and others) of patients aged 2 years or younger who underwent LTx after either Open-PE or Lap-PE from 2006 to 2017 were evaluated. RESULTS: Thirty-one (67%) out of 46 Open-PE patients and 23 (77%) out of 30 Lap-PE patients showed native liver survival with jaundice-free status at 1 year of age (p = 0.384); 29 (63%) out of 46 Open-PE patients and 19 (70%) out of 27 Lap-PE patients showed native liver survival with jaundice-free status at 2 years of age (p = 0.524); there were no significant differences. Additionally, there were 37 LTx cases after PE within 2 years of birth, including 29 Open-PE and 8 Lap-PE cases. The patients in the Lap-PE group had fewer adhesions and significantly shorter durations of surgery up to the completion of the recipient's hepatectomy and durations of post-LTx hospital stay compared to the Open-PE group. There were no differences in blood loss or duration of stay in intensive care unit between the Lap-PE and Open-PE groups. CONCLUSIONS: Jaundice-free native liver survival rate has been comparable between Open-PE and Lap-PE. Lap-PE resulted in fewer adhesions, contributing to better outcomes of subsequent LTx compared to Open-PE.

Clinical significance of cervical and ocular vestibular evoked myogenic potentials in benign paroxysmal positional vertigo: a meta-analysis.

PURPOSE: As the pathological cause of benign paroxysmal positional vertigo (BPPV), the dislocation or degeneration of otoconia in the utricle and saccule is suggested. Vestibular evoked myogenic potential (VEMP) could reflect otolithic dysfunction due to these etiologies of BPPV. The aim of this study was to validate the clinical significance of cervical (c) and ocular (o) VEMP in BPPV by a meta-analysis of previous articles. METHODS: Articles related to BPPV with data on cVEMP and oVEMP were collected. The following keywords were used to search PubMed and Scopus for English language articles: benign paroxysmal positional vertigo or BPPV and vestibular evoked myogenic potential or VEMP. RESULTS: The p13 latency in cVEMP and n1 latency in oVEMP were slightly but significantly prolonged in BPPV patients compared to control patients. AR in oVEMP of BPPV patients also showed higher value than that of control patients. However, the n23 latency and AR in cVEMP and p1 latency in oVEMP showed no significant difference between BPPV and control patients. Furthermore, latencies in VEMPs also showed no significant difference between an affected and a non-affected ear in BPPV patients. CONCLUSIONS: Our results indicated that otolith dysfunction of BPPVs was detected by latencies in VEMPs, and AR in oVEMP more sensitively reflects the difference between affected and non-affected ears in BPPV patients. The otolith dysfunction of BPPV might be induced by the systemic condition. However, the differences of latencies between BPPV patients and control patients were too small to use VEMPs as a prognostic predictor.

Efficacy of and prognosis after steroid pulse therapy in patients with poor reduction of jaundice after laparoscopic Kasai portoenterostomy.

PURPOSE: High-dose postoperative steroid therapy after Kasai portoenterostomy is reported to improve jaundice clearance and a strong anti-inflammatory activity might prevent fibrous tissue formation which is often observed at the porta hepatis in revision surgery. We started steroid pulse therapy for the patients with cessation of decrease in jaundice and aimed to evaluate the efficacy in this study. METHODS: The demographics and outcomes of patients who underwent laparoscopic Kasai portoenterostomy and received steroid pulse therapy within 2 months postoperatively between September 2014 and December 2018 were retrospectively reviewed; the therapy was determined successful when the serum total bilirubin level decreased to or below two-thirds of the pre-therapy level after 2 weeks. Patient data in the successful group were compared with those in the unsuccessful group. RESULTS: Steroid pulse therapy was successful in seven of 16 patients (43.8%). The percentage of patients whose serum total bilirubin level decreased to normal was significantly higher in the successful group at 3 months (85.7% vs. 11.1%, P = 0.0028) and after all (100% vs. 33.3%, P = 0.011). CONCLUSIONS: Steroid pulse therapy was effective for some patients. Unsuccessful cases may have little chances of jaundice clearance; revision Kasai portoenterostomy would be a good option.

Therapeutic strategy for thoracoscopic repair of esophageal atresia and its outcome.

PURPOSE: Thoracoscopic repair can be safely performed in most types of congenital esophageal atresia (EA), including in patients with long gap EA or very low birth weight. Accordingly, we performed single- or multistage thoracoscopic repair for various EA types. We aimed to report our therapeutic strategy for thoracoscopic radical surgery for treating EA and its outcome. METHODS: Outcomes of radical surgeries for treating congenital EA at our institute from 2013 to 2018 were retrospectively evaluated. RESULTS: Thirty-eight radical surgeries were evaluated: 3 Gross type-A, 1 type-B, 30 type-C, 1 type-D, and 3 type-E. The cervical approach was performed in 5 cases and thoracoscopic esophageal anastomosis in 33, including 26 single-stage (all type-C) and 7 multistage surgeries (3 type-A, 3 type-C, and 1 type-D). There were no cases of thoracotomies or intraoperative thoracoscopic surgery complications. Three cases of minor leakage were conservatively resolved. Three postoperative chylothorax surgeries (9%) and seven balloon dilatations (21%) for anastomotic stenosis were performed. CONCLUSION: Thoracoscopic radical surgery for treating EA, including single- and multistage procedures, can be performed, except in type-E cases or when the end of the proximal esophagus is located higher than the clavicle.

Usefulness of fetal magnetic resonance imaging for postnatal management of congenital lung cysts: prediction of probability for emergency surgery.

BACKGROUND: Emergency rescue lung resection is rarely performed to treat congenital lung cysts (CLCs) in neonates. Many reports have described fetal CLC treatment; however, prenatal predictors for postnatal respiratory failure have not been characterized. We hypothesized that fetal imaging findings are useful predictors of emergency surgery. METHODS: We retrospectively studied patients with CLC who underwent lung surgery during the neonatal period in our hospital between January 2001 and December 2015. The demographic data, fetal imaging findings, and intra- and postoperative courses of patients who underwent emergency surgery (Em group) were compared with those of patients who received elective surgery, i.e., non-emergency surgery (Ne group). RESULTS: The Em group and Ne group included 7 and 11 patients, respectively. No significant difference was noted in gestational age, time at prenatal diagnosis, birth weight, and body weight at surgery. The volumes of contralateral lung per thoracic volume were significantly smaller in the Em group than in the Ne group (p = 0.0188). Mediastinal compression was more common in the Em group (7/7) than in the Ne group (4/11) (p = 0.0128). CONCLUSIONS: This is the report describing neonatal emergency lobectomy in patients with CLC evaluated by fetal MRI using the lung volume ratio and mediastinal shift. In patients with CLC, mediastinal shift and significant decreases in contralateral lung volumes during the fetal stages are good prenatal predictors of postnatal emergency lung resection.

Introduction of resection of intrahepatic bile duct stenosis-causing membrane or septum into laparoscopic choledochal cyst excision.

PURPOSE: We previously showed that meticulous probing and resection of the intrahepatic bile duct stenosis (IHBDS)-causing membrane or septum was effective in preventing hepatolithiasis after choledochal cyst excisions in open surgeries. Then, we introduced this maneuver into laparoscopic choledochal cyst excisions in 2014 and performed routine resections since then. The aim of this study was to show the feasibility of this method in laparoscopic surgery. METHODS: We retrospectively reviewed the demographics and outcomes of patients who underwent laparoscopic choledochal cyst excisions at our hospital between January 2014 and December 2017. The patients who underwent surgical treatment for IHBDS-causing membrane or septum were compared with those who did not undergo the procedure. The outcomes of the patients with IHBDS were also compared between patients who were ≥ 3 years of age and those < 3 years at operation. RESULTS: Seventeen of 35 patients underwent laparoscopic resection of IHBDS-causing membrane or septum. There were no complications related to the procedure although the operative time and intraoperative bleeding amount increased in the patients with IHBDS who were ≥ 3 years of age. CONCLUSIONS: Meticulous probing and excision of the IHBDS-causing membrane or septum is safe and feasible during laparoscopic choledochal cyst excision.

Long-term outcomes and complications after laparoscopic-assisted anorectoplasty vs. posterior sagittal anorectoplasty for high- and intermediate-type anorectal malformation.

PURPOSE: Laparoscopic-assisted anorectoplasty (LAARP) is a minimally invasive procedure in which the levator ani muscle is left to potentially improve postoperative fecal continence. This study aimed to retrospectively evaluate postoperative complications and long-term outcomes of fecal continence after LAARP and compare them to those after posterior sagittal anorectoplasty (PSARP). METHODS: Forty-five male patients with high and intermediate anorectal malformation (aged ≥ 4 years) who underwent LAARP or PSARP (LAARP 29, PSARP 16) from 1999 to 2013 were included. Postoperative complications and postoperative fecal continence were retrospectively evaluated and compared. Postoperative complications were also compared before and after introducing a urethroscope during fistula resection. RESULTS: Complications after LAARP and PSARP were seen in 12 vs. 2 cases (p = 0.09) of mucosal prolapse and in 9 vs. 1 case (p = 0.07) of posterior urethral diverticulum (PUD), respectively. The incidence of PUD decreased after introduction of a urethroscopy from 40% in 8/20 cases to 11% in 1/9 cases. No significant difference was found in terms of fecal continence in both groups. CONCLUSION: Through our study, greater improvement of postoperative fecal continence after LAARP has not been shown. LAARP was at higher risk for mucosal prolapse and PUD. However, precise dissection of the urethral fistula could be performed after the introduction of urethroscopy.

Investigation of the feasibility and safety of single-stage anorectoplasty in neonates with anovestibular fistula.

PURPOSE: Anovestibular fistula (AVF) is the most common type of anorectal malformation in females. Delayed anorectoplasty with fistula dilatation is commonly performed during infancy; however, we have been actively performing anorectoplasty in neonates. We report the surgical complications and postoperative defecation function associated with single-stage anorectoplasty performed in neonates. METHODS: Patients who underwent surgery for AVF between 2007 and 2017 at two institutions were retrospectively studied. The operation time, amount of bleeding, time to start oral intake, perioperative complications, and Kelly's score were compared among patients who underwent surgery as neonates and those who underwent surgery as infants. RESULTS: Eighteen neonates and 17 infants underwent anterior sagittal anorectoplasty. The median operation time and time to start oral intake were significantly shorter in the neonatal group (72 min; 3 days, respectively) than in the infant group (110 min, p = 0.0002; 5 days, p = 0.0024, respectively). Postoperative wound disruption was significantly more frequent in the infant group. Of the ten patients each in the neonatal and infant groups, there was no significant difference in Kelly's score at age ≥ 4 years. CONCLUSION: Single-stage anorectoplasty in neonates with AVF can be feasibly performed and does not impair postoperative defecation function. LEVELS OF EVIDENCE: III.

Single-stage laparoscopic transanal pull-through modified Swenson procedure without leaving a muscular cuff for short- and long-type Hirschsprung disease: a comparative study.

PURPOSE: The Soave procedure (SO) is performed most commonly for Hirschsprung disease. SO reduces the risk of injury to the pelvic structures; however, a residual aganglionic muscle cuff could interfere with bowel movement and lead to obstructive enterocolitis. The Swenson procedure is considered ideal in terms of peristalsis. Currently, laparoscopic surgery provides better visualization and facilitates precise dissection, possibly leading to feasible performance of the laparoscopic modified Swenson procedure (SW). We present our operative technique and the efficacy of the SW compared with that of SO. METHODS: We retrospectively reviewed the records of 16 and 27 patients who underwent SW and SO, respectively, between 2012 and 2017. RESULTS: Operative time, blood loss, length of stay, and frequency of bowel movements showed no significant difference between the two groups. In the SW group, temporary dysuria occurred in one patient, postoperative enterocolitis in two, wound infection in one, and severe perianal excoriation in four, whereas in the SO group, obstructive symptoms occurred in three patients, small-bowel obstruction in one, and severe perianal excoriation in three. The complications and outcomes were comparable between both groups. CONCLUSION: Laparoscopic SW was safe and feasible for the short-term follow-up outcomes.

Oral administration of eicosapentaenoic acid suppresses liver fibrosis in postoperative patients with biliary atresia.

PURPOSE: Biliary atresia (BA) is characterized by progressive inflammation of the biliary system. This inflammation persists and causes liver fibrosis, although jaundice disappears after Kasai portoenterostomy (KP). We aimed to confirm whether the oral administration of eicosapentaenoic acid (EPA) suppresses liver fibrosis in postoperative patients with BA. METHODS: We reviewed patients who underwent laparoscopic KP (lapKP) between January 2014 and September 2017. From December 2016, 30 mg/kg/day of EPA was orally administered to patients who opted to take medicine (EPA group). Patients who did not receive EPA were assigned to the non-EPA group. Mac-2 binding protein sugar chain modified isomer (M2BPGi) and hyaluronic acid (HA) levels were compared between the two groups in patients showing disappearance of jaundice at 6 months after the first lapKP. RESULTS: Seventeen patients in the non-EPA group and 11 in the EPA group were enrolled. At 6 months after the first lapKP, 10 patients in the non-EPA group and six in the EPA group were without jaundice. M2BPGi and HA levels were significantly lower in the EPA group. CONCLUSIONS: Liver fibrosis was suppressed in patients without jaundice 6 months after lapKP, who were administered EPA. We believe that periductular inflammation was alleviated by EPA supplementation.

Case report of Pierre Robin sequence with severe upper airway obstruction who was rescued by fiberoptic nasotracheal intubation.

BACKGROUND: Pierre Robin sequence (PRS) refers to the association of micrognathia, glossoptosis, and airway obstruction. Cases with severe dyspnea due to upper airway obstruction immediately after birth are very rare. We here report two cases with PRS who developed severe dyspnea due to morphological abnormality immediately after birth and were rescued by fiberoptic nasotracheal intubation. CASE PRESENTATION: The patient in case 1 had micrognathia and cleft palate, and his tongue protruded into the nasal cavity via a cleft palate. His invaginated tongue was considered an extreme type of glossoptosis and he was diagnosed as Pierre Robin sequence. The patient in case 2 also had micrognathia and cleft palate same as case 1 and accompanied some anomalad. Her chromosome analysis confirmed a diagnosis of 1p36 deletion syndrome and she diagnosed as 1p36 deletion syndrome complicated with Pierre Robin sequence. In both cases, tongue protruded into the nasal cavity via a cleft palate occupied pharynx and nasal cavity, resulting in severe dyspnea. Only the backside of the tongue was visible by laryngoscopy and oropharyngeal intubation was impossible. Therefore, fiberoptic nasotracheal intubation was done to secure the airway for resuscitation. CONCLUSION: We conclude that extreme type of glossoptosis in PRS concludes tongue invaginated into nasal cavity which have not reported before and that such cases require resuscitation by fiberoptic intubation immediately after birth. As such, neonatologists should obtain the skill of fiberoptic intubation.

Review of redo-Kasai portoenterostomy for biliary atresia in the transition to the liver transplantation era.

Portoenterostomy (PE) is the standard therapy for biliary atresia (BA). PE offers the chance of survival to children with BA. PE was the ultimate therapeutic modality for BA before liver transplantation (LT) was available. Failure of biliary drainage with PE was almost invariably fatal in children with BA. In such cases, redo-PE was performed to salvage patients following PE failure. PE remains the standard first treatment for BA despite the availability of LT. Further, redo-PE is also performed in a limited number of cases despite the development of LT as an alternative means of PE. However, there is concern that redo-PE increases morbidity at the time of subsequent LT. Laparoscopic redo-PE has recently been described. Laparoscopic redo-PE is expected to reduce complications of LT by preventing abdominal adhesion associated with repetitive surgery. In the present article, the future utility of redo-PE and the history of its changing roles are reviewed.

Comparison of outcomes of thoracoscopic primary repair of gross type C esophageal atresia performed by qualified and non-qualified surgeons.

PURPOSE: Although thoracoscopic repair of esophageal atresia has become widespread, most studies are based on operations performed by expert surgeons. Therefore, the outcomes of operations performed by non-expert surgeons are not well known. The aim of this study was to compare outcomes based on operator skill level. METHODS: We retrospectively reviewed the demographics and outcomes of patients with Gross type C esophageal atresia, who underwent primary thoracoscopic repair at our hospital between January 2014 and August 2016. Outcomes of surgeries performed by qualified surgeons, as determined by the Japanese Society for Endoscopic Surgery were compared with those of non-qualified surgeons. All operations were performed by or under the supervision of one qualified surgeon. RESULTS: Nine operations were performed by qualified surgeons and six operations by non-qualified surgeons with >10 years of experience in surgery. None of the patients developed anastomotic leakage or recurrent tracheoesophageal fistula. However, the operative time and rate of stricture formation at the beginning of the weaning period were significantly higher in the latter group (P = 0.008 and 0.044). CONCLUSIONS: Although supervision of experts would improve results in thoracoscopic repair of esophageal atresia, the results indicate that good skill is necessary to avoid anastomotic stricture.

Left thoracoscopic two-stage repair of tracheoesophageal fistula with a right aortic arch and a vascular ring.

A right aortic arch (RAA) is found in 5% of neonates with tracheoesophageal fistulae (TEF) and may be associated with vascular rings. Oesophageal repairs for TEF with an RAA via the right chest often pose surgical difficulties. We report for the first time in the world a successful two-stage repair by left-sided thoracoscope for TEF with an RAA and a vascular ring. We switched from right to left thoracoscopy after finding an RAA. A proximal oesophageal pouch was hemmed into the vascular ring; therefore, we selected a two-stage repair. The TEF was resected and simple internal traction was placed into the oesophagus at the first stage. Detailed examination showed the patent ductus arteriosus (PDA) completing a vascular ring. The subsequent primary oesophago-oesophagostomy and dissection of PDA was performed by left-sided thoracoscope. Therefore, left thoracoscopic repair is safe and feasible for treating TEF with an RAA and a vascular ring.

Transient, afferent input-dependent, postnatal niche for neural progenitor cells in the cochlear nucleus.

In the cochlear nucleus (CN), the first central relay of the auditory pathway, the survival of neurons during the first weeks after birth depends on afferent innervation from the cochlea. Although input-dependent neuron survival has been extensively studied in the CN, neurogenesis has not been evaluated as a possible mechanism of postnatal plasticity. Here we show that new neurons are born in the CN during the critical period of postnatal plasticity. Coincidently, we found a population of neural progenitor cells that are controlled by a complex interplay of Wnt, Notch, and TGFß/BMP signaling, in which low levels of TGFß/BMP signaling are permissive for progenitor proliferation that is promoted by Wnt and Notch activation. We further show that cells with activated Wnt signaling reside in the CN and that these cells have high propensity for neurosphere formation. Cochlear ablation resulted in diminishment of progenitors and Wnt/ß-catenin-active cells, suggesting that the neonatal CN maintains an afferent innervation-dependent population of progenitor cells that display active canonical Wnt signaling.

Comparing surgical outcomes of complete thoracoscopic lobectomy for congenital cystic lung disease between neonatal and infantile patients.

Thoracoscopic lobectomy has recently become a widely used surgical treatment for congenital cystic lung disease, but significant issues can arise in some cases, such as a limited working space in neonates, a limited view in cases involving large cystic lesions. We reviewed the treatment outcomes of neonates that underwent complete thoracoscopic lobectomy or segmentectomy and evaluated the operative difficulties. From January 2008 to October 2015, 38 patients under the age of 1 year underwent complete thoracoscopic lobectomy or segmentectomy for cystic lung disease at our institution. We compared the intra- and postoperative data of the neonate group (N group) with those of the infant group (I group). Fourteen and 24 patients underwent thoracoscopic lobectomy or segmentectomy in the N group and I group, respectively. The operative time and amount of intraoperative blood loss did not differ significantly between the two groups (p=0.694 and p=0.878, respectively), but the duration of the postoperative hospitalization period was significantly longer (p<0.01) in the N group. The frequencies of postoperative complications did not differ significantly between the two groups. The operative time of thoracoscopic lobectomy was significantly longer in cases involving incomplete lobar fissures than in those involving normal lobar fissures. Surgical outcomes of complete thoracoscopic lobectomy for neonatal cases are almost equivalent compared with infantile cases, and thoracoscopic lobectomy takes longer in cases involving incomplete lobar fissures.

Incidence of contralateral patent processus vaginalis in relation to age at laparoscopic percutaneous extraperitoneal closure for pediatric inguinal hernia.

INTRODUCTION: Laparoscopic percutaneous extraperitoneal closure (LPEC) allows the surgeon to look for contralateral patent processus vaginalis (CPPV) directly. We investigated the incidence of CPPV in relation to age at LPEC. METHODS: Following Institutional Review Board approval, 1232 patients ranging in age from 2 months old to 15 years old (median 4.7 years), who underwent LPEC, were investigated retrospectively. Patients were divided into five groups based on their age at surgery: younger than 1, 1-2, 2-4, 4-6 years, and older than 6 years. The incidence of CPPV being detected by preoperative ultrasonography or laparoscopy was compared among these groups. Statistical analyses were performed using the Chi-square test or Cochran-Armitage trend test, and p < 0.05 was considered significant. RESULTS: The incidence of CPPV detected by ultrasonography decreased as the age increased (p < 0.0001), whereas the incidence of CPPV newly revealed by laparoscopy increased as age increased (p = 0.0001). There were no significant differences in the incidence of CPPV in patients with unilateral hernia among the five age groups (p = 0.74). CONCLUSIONS: These results showed that the incidence of CPPV in patients with unilateral inguinal hernia did not change in relation to their age.