New ultrasound features in diagnosing fetal anal atresia: a multicenter prospective cohort study.

This research aimed to assess the validity of ultrasound scans with new features in detecting fetal anal atresia and verify the effectiveness of these new features. Additionally, we aimed at investigating the perinatal incidence of anal atresia. This multicenter prospective study recruited 94,617 normal gravidas and 84 gravidas with anal atresia fetuses. The gold standard for diagnosing perinatal anal atresia is routine neonatal anus examinations. The incidence calculation was based on the results of the gold standard. The validity of our new approach was evaluated via a diagnostic test involving all 94,701 subjects. The effectiveness of our new features was assessed through an ablation study in a randomly established new dataset, with the ratio of anal atresia to non-anal atresia cases of 1:4. The annual perinatal incidence of anal atresia between 2019 and 2023 ranges from 0.57‰ to 1.29‰. Our new method performed great regarding the Youden index, diagnostic odds ratio (DOR), area under the curve (AUC) of the receiver operating characteristic curve (ROCC), AUC of the precision-recall curve (PRC), F1-score, and Cramer's V. In the ablation study, our new approach surpassed its competitors concerning Youden index, DOR, AUC of the ROCC, and AUC of the PRC. Ultrasound scans show high validity and clinical value in detecting fetal anal atresia. Our new ultrasound features significantly promote the detection of fetal anal atresia.

Infracoccygeal/transperineal window: new method to prenatally diagnose and classify level of anal atresia.

OBJECTIVES: To introduce a two-dimensional sonographic method to assess the fetal anus, and to evaluate the feasibility of this method to diagnose anal atresia prenatally and identify the presence or absence of anoperineal fistula (in males) and anovestibular fistula (in females). METHODS: This was an observational study of suspected cases of anal atresia referred to a single center in Israel between August 2018 and October 2023. In addition to conventional evaluation of the perineum in the axial plane, fetuses referred to our center for suspected malformation were scanned with a new method termed the 'infracoccygeal/transperineal window'. This window consisted of a midsagittal view of the fetal pelvis, including the distal rectum and the anal canal. Normal anatomy was confirmed when the anal canal was continuous with the rectum and terminated at the expected location on the perineum. In female fetuses, the normal anal canal runs parallel to the vaginal canal and diverges posteriorly, terminating at the perineal skin, distant from the vestibule. In male fetuses, the normal anal canal diverges posteriorly in relation to the corpora cavernosa, terminating at the perineal skin, distant from the scrotum. High anal atresia was identified when a blind-ending rectal pouch was demonstrated in the pelvis without a fistula to the perineum or vestibule. Low anal atresia was determined when a rectal pouch was continuous with an anteriorly deflected fistula. In females, the fistula converges with the vaginal canal, terminating at the vestibule; in males, the fistula deflects anteriorly, terminating at the base of the scrotum. Postnatally, the diagnosis and type of anal atresia were confirmed through physical examination with direct visualization of the fistula, radiographic studies, surgical examination and/or postmortem autopsy. RESULTS: Of the 16 fetuses diagnosed prenatally with anal atresia, eight were suspected to have low anal atresia and eight were suspected to have high anal atresia. The median gestational age at diagnosis was 23 (range, 14-37) weeks. All cases showed additional structural malformation. Eleven patients opted for termination of pregnancy, of which four had low anal atresia and seven had high anal atresia. Postnatal confirmation was not available in four cases due to curettage-induced mutilation or in-utero degradation following selective termination of the affected twin, leaving 12 cases for analysis, of which seven were diagnosed with low anal atresia and five with high anal atresia. In these 12 cases, all prenatal diagnoses were confirmed as correct, rendering 100% sensitivity and 100% specificity in this high-risk fetal population. CONCLUSIONS: The infracoccygeal/transperineal window is an effective method to detect and classify the level of anal atresia prenatally. This may improve prediction of postnatal fetal continence and optimize prenatal counseling. © 2024 International Society of Ultrasound in Obstetrics and Gynecology.

Functional Outcomes of Patients Who Underwent Anorectal Malformation Repair Using MRI Guidance.

BACKGROUND: Despite the initiation of minimally invasive laparoscopic techniques, the majority of patients who undergo anorectal malformation repair still experience functional bowel issues in childhood, including constipation and fecal incontinence. In this study, we evaluate the functional outcomes of a procedure in which magnetic resonance imaging guidance is used during initial laparoscopic repair to better locate the epicenter of the sphincter muscle complex and pelvic floor with the goal of more accurate placement of the neoanus and improved functional outcomes. METHODS: A retrospective chart review evaluated demographic, operative, and outcome details for patients who underwent this procedure. A telephone survey was employed to determine levels of social continence using the validated Baylor Continence Scale and to determine what type of bowel management is used. RESULTS: Twenty-six patients were included. Median age at operation was 7 months, and median age at follow-up was 4 years old, with a range of 1-9. Bowel management regimen results revealed that 19 % (n = 5) use no bowel management regimen, 58 % (n = 15) use laxatives only, and 23 % (n = 6) use enemas. Enema use was not associated with different spine or sacral anomalies (p = 0.77). Fifteen patients (58 %) answered the Baylor Continence Scale questions and had a median score of 14. No difference was found in scores when accounting for lesion level (p = 0.43), quality of needle placement (p = 0.46), or quality of sphincter muscles (p = 0.75). CONCLUSIONS: Using MRI guidance in the repair of anorectal malformations shows promise in both the qualitative and quantitative functional outcomes of this complex patient population. LEVEL OF EVIDENCE: Level III.

Imaging of anorectal malformations: where are we now? Abdominal imaging task force of the European Society of Paediatric Radiology.

Anorectal and cloacal malformations are a broad mix of congenital abnormalities related to the distal rectum and anus. Confusion exists between all the forms in this large and heterogeneous group. The spectrum includes everything from anal stenosis, ventral anus, anal atresia (with and without fistula) and the full spectrum of cloacal malformations. Imaging in these conditions is done through the whole armamentarium of radiologic modalities, with very different imaging strategies seen across the centres where these conditions are managed. In 2017, the European Society of Paediatric Radiology (ESPR) abdominal imaging task force issued recommendations on the imaging algorithm and standards for imaging anorectal malformations. This was followed by further letters and clarifications together with an active multispecialty session on the different imaging modalities for anorectal malformations at the 2018 ESPR meeting in Berlin. Through this paper, the abdominal task force updates its guidelines and recommended imaging algorithm for anorectal malformations.

Intraoperative visualization of urethra using illuminating catheter in laparoscopy-assisted anorectoplasty for imperforated anus-A novel and safe technique for preventing urethral injury.

PURPOSE: In this study, we used a near-infrared ray catheter (NIRC) to visualize the urethral line. We herein report our intraoperative visualization technique of the urethra using an illuminating catheter in laparoscopy-assisted anorectoplasty (LAARP) for imperforated anus. PATIENT AND SURGICAL TECHNIQUE: A 3.0-kg term male neonate with anorectal malformation was delivered. An invertogram revealed the type as intermediate. Transverse colostomy was performed at the left upper abdomen. A recto-bulbar urethral fistula (RBUF) was diagnosed via distal colostogram and voiding cystourethrogram. LAARP was planned at 6 months of age. We performed the operation with four trocars. A 45° 5-mm scope was used to clearly view the deep pelvic space. Before starting rectal dissection, a 6-Fr pig-tail-type NIRC was inserted through the external opening of the urethra to visualize the urethra during the laparoscopic procedure. The catheter tip was placed in the bladder, and excretion of urine was maintained through the NIRC during the procedures. While dissecting the deep pelvic space between the posterior wall of the urethra and anterior wall of the rectum, the exact line of the urethra was clearly confirmed by overlay images of the NIRC. The RBUF was dissected safely using this innovative image-guided technique. Anoplasty was performed between the rectal stump and perineal skin. The postoperative course was uneventful. Oral intake was started on postoperative day 1. Postoperative dynamic urography showed no complications. CONCLUSION: An NIRC is useful for detecting the urethra during LAARP.

Significance of the 'line sign' in the diagnosis of congenital imperforate anus on prenatal ultrasound.

BACKGROUND: The prenatal diagnosis of foetal imperforate anus is difficult. Most previous studies have been case reports. To provide useful information for diagnosing foetal imperforate anus, a retrospective review of diagnostic approaches was conducted. Ultrasonography was performed in 19 cases of foetal imperforate anus from 2016 to 2019 at our prenatal diagnostic centre. The prenatal sonographic features and outcomes of each case were collected and evaluated. RESULT: The anal sphincter of a normal foetus shows the 'target sign' on cross-sectional observation. Of the 19 cases of imperforate anus, 16 cases were diagnosed by the ultrasound image feature called the 'line sign'. 1 case with tail degeneration was low type imperforate anus with the irregular 'target sign' not a real 'target sign'. There was two false-negative case, in which the 'target sign' was found, but irregular. CONCLUSION: In this study, we find that the anus of a foetus with imperforate anus presents a 'line sign' on sonographic observation. The absence of the 'target sign' and then the presence of the 'line sign' can assist in the diagnosis of imperforate anus. The 'line sign' can be used as a secondary assessment to determine the type of the malformation following non visualization of the 'target sign'. The higher the position of the imperforate anus is, the more obvious the 'line sign'. It is worth noting that the finding of the short 'line sign' and irregularr 'target sign' can not ignore the low type imperforate anus.

Anal atresia as the diagnostic clue in VACTERL association: A first-trimester case report.

Anal atresia is the most common malformation occurring in VACTERL association, but it is difficult to diagnose antenatally. We herein present a case of fetal anal atresia in VACTERL association diagnosed by ultrasonography and supported by autopsy. This case emphasizes the clues to ultrasonographic diagnosis of anal atresia at 11-13+6 weeks of gestation, promoting increased awareness of VACTERL association during first-trimester screening.

Sonographic detection and localization of fistulas in fetuses with imperforate anus: Case reports.

Imperforate anus (IA) requires urgent treatment after birth, which is dependent on the type of IA, and is also frequently associated with other congenital abnormalities. Most patients with IA have an accompanying fistula, whose location is strongly associated with the type of IA. The fistula location can be a key factor in defining appropriate treatment, especially in neonates presenting with severe associated abnormalities. Herein, we report three cases of IA in which fistulas were detected and localized prenatally. Examination of the fetal pelvis through the sagittal or coronal view, using high-frequency transducers, revealed the location of the fistulas. In particular, the sagittal view obtained using the fetal infracoccygeal or perineal approach allowed us to determine the precise anatomy of the fistulas. Neonatal assessment confirmed the fistula locations. We recommend using the sagittal view obtained using the fetal infracoccygeal or perineal approach with high-frequency transducers to assess fistulas in fetuses with IA.

Turbulent Cerebrospinal Fluid Flow in Enlarging Terminal Myelocystocele.

Terminal myelocystocele is a rare type of neural tube malformation, consisting of a skin-covered lumbosacral mass, highly associated with other complex abdominal malformations within the OIES complex (omphalocele, imperforate anus, exstrophy of the cloaca and spinal defects). We present a case of a premature female with an extensive lumbosacral mass at birth, as well as an omphalocele, cloacal exstrophy, renal abnormalities, and sacral agenesis. Lumbar magnetic resonance imaging revealed a meningocele sac herniating through the bone defects and containing a syringocele sac. Advanced imaging techniques showed turbulent cerebrospinal fluid flow. At control, 4 weeks later, the defect doubled in size. The myelocystocele sac was evacuated and closed, and the patient persisted with paraparesis. The role of cerebrospinal fluid flow analysis is well established in Chiari-type malformations, in which turbulent flow within the syrinx is related to a better outcome after surgery. It is possible that the same principle could be applied to other spinal malformations, as shown in this case of terminal myelocystocele.

Key anatomic findings on fetal ultrasound and MRI in the prenatal diagnosis of bladder and cloacal exstrophy.

INTRODUCTION: Prenatal determination of bladder exstrophy (BE) or cloacal exstrophy (CE), known also as the omphalocele-exstrophy-imperforate anus-spinal anomaly complex (OEIS), is challenging. Distinguishing between BE and CE is important because children with CE have many more challenges initially and during their lifetime. An accurate diagnosis is critical when counselling expectant parents. We hypothesized that there are key imaging features that can distinguish BE from CE, and that there are areas of diagnostic concordance and discordance between fetal ultrasound (fUS) and fetal MRI (fMRI) among these entities. MATERIALS AND METHODS: We queried a single institutional IRB-approved registry of children with BE and CE to identify those with accessible fetal imaging from 2000 to 2018, and formal interpretations were collected. Two pediatric radiologists performed independent retrospective blinded review of the images. Criteria evaluated included: genitalia, kidneys, bowel appearance, presence of anal dimple, location of insertion of umbilical cord into the abdomen relative to the abdominal wall defect, umbilical vessels, bladder protuberance, presence of omphalocele, and spine/neural cord abnormalities. We evaluated concordance between radiologic interpretations and postnatal diagnosis, as well as between specific findings in the two diagnostic modalities. RESULTS: Twenty-one infants born between 2000 and 2018 with BE or CE had fetal imaging for review: 15 had both fUS and fMRI, 2 had fUS alone, and 4 fMRI alone. There was 100% concordance between fUS and fMRI in evaluating kidneys, presence of anal dimple, location of abdominal insertion of umbilical cord relative to the defect, number of umbilical vessels, and spine abnormalities/level of neural cord termination. The following discrepancies were observed: 1) genitalia and bowel appearance, and bladder protuberance in 1/15 (6.7%); 2) presence of an omphalocele in 2/15 (13.3%). Of the initial radiologic interpretations, 4/17 (23.5%) of fUS and 2/19 (10.5%) of fMRI erroneously were interpreted as on the OEIS spectrum when the post-natal diagnosis was BE. Errors in diagnosis were due to a protuberant bladder plate extending beyond the plane of the abdominal wall with bowel loops posteriorly mimicking an omphalocele. In all of these BE cases, the abdominal wall defect was located inferior to the umbilical cord insertion on the abdominal wall. CONCLUSION: An everting bladder plate with bowel loops posterior to the plate in classic BE may be misdiagnosed as CE. Identification of the location of umbilical cord insertion relative to the abdominal wall defect, with fetal US or MRI, results in the correct differentiation between BE and CE.

Severe forms of Johanson-Blizzard syndrome caused by two novel compound heterozygous variants in UBR1: Clinical manifestations, imaging findings and molecular genetics.

Johanson-Blizzard Syndrome (JBS) is a rare autosomal recessive genetic disorder characterized by exocrine pancreatic insufficiency, distinct abnormal facial appearance and varying degrees of growth retardation. Variants in UBR1 gene are considered to be responsible for the syndrome. Here, we describe a 3-year old boy, who visited our clinic for severe growth retardation and frequent oily diarrhea. The physical examination revealed nasal alae aplasia, scalp defect, and maldescent of left testicle. Transabdominal ultrasound and computed tomography scan of his abdomen demonstrated complete fatty replacement of the pancreas. The clinical, laboratory, and imaging findings strongly suggest the diagnosis of hereditary pancreatitis. Whole exome sequencing revealed two rare compound heterozygous variants, c.2511T > G (p.H837Q) and c.1188T > G (p.Y396X), in the UBR1 gene of this boy, so, the diagnosis of JBS was established. This is the first report of Chinese patient with JBS, and our study indicates that transabdominal ultrasound and computed tomography are two useful and noninvasive imaging methods for the diagnosis and evaluation of JBS, and identification of these two novel variants expands the database of UBR1 gene variants. Furthermore, with the availability of the identification technology for these variants, prenatal diagnosis could be offered for future pregnancies.

Prenatal and postnatal imaging techniques in the evaluation of disorders of sex development.

Imaging of the reproductive tract is challenging and requires a general knowledge of congenital variations in anatomy. The anatomy of the developing fetus, whether a male phenotype or female phenotype, is also a dynamic process with many changes occurring during gestation. Families may ask details about the genitalia during prenatal imaging and when variations in what is thought to be normal are present, further investigation is sometimes needed to make sense of what is seen. This overview will describe categories of disorders of sex development (DSD), whether chromosomal or structural or both, and the current state of imaging of these anomalies.

Prenatal diagnosis of congenital megalourethra with imperforate anus.

BACKGROUND: Congenital megalourethra is a rare prenatal finding while prenatal diagnosis of imperforate anus poses high challenge. This is the first prenatally ultrasound diagnosed case which had congenital megalourethra and imperforate anus. This case demonstrated the possibility of using the prenatal imaging findings to evaluate the postnatal prognostic outcomes in multi-organ anomalies. CASE: We present a case of congenital megalourethra, diagnosed prenatally at 22 weeks' gestation, in which the penis appeared severe dilated with complete absence of the corpora spongiosa and cavernosa. This case also revealed absence of perianal muscle which was in associated with imperforate anus. Detailed prenatal ultrasonographic findings predicted the high possibility of poor outcome of the fetus in the pulmonary, renal, and sexual functions. CONCLUSION: This case serves to identify not only the marked bilateral hydronephrosis features but also the striking lower urethral malformation with obstruction flow effect of the penis. Indeed we believe this is the first case report of a rare case of fetal megalourethra associated with imperforate anus at early second trimester on ultrasonography imaging.

Contrast-Enhanced Colosonography for the Evaluation of Children With an Imperforate Anus.

This case series describes a novel method for showing the preoperative anatomy of children with anorectal malformations using ultrasound contrast, which we have termed "contrast-enhanced colosonography (ceCS)." Six patients with anorectal malformations without a perineal fistula were studied both by fluoroscopic distal colostography and ceCS, and their results were confirmed surgically. Contrast-enhanced CS precisely showed the complex anatomic relationships in all cases. Compared to traditional fluoroscopic studies, ceCS has the benefit of no associated ionizing radiation and thus is safer for children.

Genital Mobilization of Intravesical Phallus Associated With Covered Cloacal Exstrophy: A Case Report.

Cloacal exstrophy is the most severe form of the exstrophy-epispadias complex, occurring in approximately 1 of every 200,000 to 400,000 live births. Variant such as covered cloacal exstrophy presentations are only one-tenth as common. Although exstrophy-epispadias complexes include genital anomalies, intravesical phallus is very rare. We report an extremely rare case of intravesical phallus with covered cloacal exstrophy that was successfully treated by phallic mobilization.

Distance Between the Distal Rectal Pouch and Perineum in Neonates of Low-Birth Weight With Imperforate Anus.

This study was to evaluate the correlation between birth weight and the distance between distal rectal pouch and perineum (P-P distance) and to determine a cutoff value for P-P distance to diagnose low-type imperforate anus in neonates with low-birth weight (LBW).We included 15 neonates with LBW (mean weight, 2012 ± 470 g; range, 906-2452 g) and imperforate anus (surgically confirmed: 11 low type and 3/1 intermediate/high type), who underwent ultrasonography on the day after birth. Type of imperforate anus was defined based on the International Classification of Anorectal Anomalies. The P-P distances on ultrasonograms were measured. Pearson correlation coefficient test and receiver operating characteristic curve were used for statistical analyses.Among all 15 neonates, nonsignificant correlation was observed between the birth weight and P-P distance (r = 0.36; P = 0.18). Mean P-P distance was 9.0 ± 6.6 mm (range, 1.0-24.0 mm) in all neonates, 5.7 ± 2.8 mm (range, 1.0-11.0 mm) in the 11 neonates with low-type imperforate anus, and 18.3 ± 9.1 mm (range, 14.0-24.0 mm) in the 4 neonates with intermediate-/high-type imperforate anus. Using cutoff P-P distance of 12.5 mm, sensitivity and specificity for diagnosis of low-type imperforate anus were 100% (11/11) and 100% (4/4), respectively.In conclusion, nonsignificant correlation was observed between P-P distance and birth weight, and cutoff P-P distance to diagnose low-type imperforate anus was 12.5 mm. Despite the very small sample size in our study, and only 4 neonates with intermediate-/high-type imperforate anus, these findings are important because surgical management whether transperineal anoplasty or diverting colostomy is decided based on the type of imperforate anus, and P-P distance to diagnose the type of imperforate anus was feasible even in neonates with LBW.

Augmented-pressure distal colostogram: the most important diagnostic tool for planning definitive surgical repair of anorectal malformations in boys.

There is little current literature on the augmented-pressure distal colostogram, the single most important diagnostic study performed in boys with imperforate anus prior to definitive repair. Accurate understanding of the anatomy of the anorectal malformation including an associated fistulous communication between the rectum and the urogenital tract is essential for optimal surgical management. Specifically, the position of the rectal pouch and recto-urinary fistula relative to posterior sagittal structures of the perineum, especially the sacral spine, dictates the operative approach. This pictorial essay is a guide for those who encounter such children with relative infrequency to become more comfortable with the technique. We report how to perform this radiologic exam and the potential pitfalls from our experience of performing the technique in our large pediatric colorectal practice.

Diagnostic Accuracy of Sonography for Detection of a Fistula on the Birth Day in Neonates With an Imperforate Anus: Comparison of Diagnostic Performance Between Suprapubic and Perineal Approaches.

OBJECTIVES: To evaluate the diagnostic accuracy of sonography for detection of an internal fistula on the birth day in neonates with an imperforate anus and to compare the diagnostic performance between the suprapubic and perineal approaches. METHODS: We included 46 neonates with an imperforate anus (29 low type and 17 intermediate/high type) who underwent sonography by both the suprapubic and perineal approaches on the birth day. Thirty-nine neonates had internal fistulas, and 12 did not, as surgically proven. Two blinded radiologists evaluated the suprapubic and perineal sonograms for the presence of the internal fistula in consensus. A final diagnosis of the internal fistula was determined on the basis of the findings of both approaches. A receiver operating characteristic analysis was used to compare the diagnostic performance for detection of an internal fistula between the suprapubic and perineal approaches. RESULTS: The sensitivity, specificity, and accuracy of the final diagnosis based on the findings of suprapubic, perineal, and both approaches were 52.9%, 79.4%, and 79.4%; 75.5%, 75.5%, and 75.5%; and 58.7%, 78.3%, and 78.3%, respectively. The diagnostic performance of the perineal approach was significantly better than that of the suprapubic approach (P < .0001). CONCLUSIONS: The diagnostic accuracy of sonography for detection of an internal fistula on the birth day exceeded 75% in neonates with an imperforate anus, and sonography on the birth day is feasible. The perineal approach had superior diagnostic performance over the suprapubic approach. Thus, when evaluating an internal fistula by sonography, we recommend using the perineal approach in addition to the suprapubic approach.