Congenital Obstruction Research Articles

195 Aberrant Brain Biomechanics Initiates Ventricular Dilation in a Genetic Subtype of Congenital Hydrocephalus

INTRODUCTION: We have previously shown using human genetics and mouse models that TRIM71 is a bona fide disease gene causing human congenital hydrocephalus. Disease-associated mutations in TRIM71 disrupt neural stem cell proliferation, however how these developmental effects physiologically lead to ventricular dilation is not clear. METHODS: We developed a number of novel methods to characterize cerebrospinal fluid (CSF) circulation, including cilia-generated currents and bulk flow. We then used these methods to comprehensively characterize CSF dynamics and intracranial physiology in hydrocephalic Trim71R595H/+ mice that harbor the same point mutation found in human hydrocephalus patients. RESULTS: We found that in hydrocephalic Trim71R595H/+ mice, impaired neurogenesis results in a hypoplastic cerebrocortical wall that exhibits loss of stiffness and elasticity. This leads to a floppy hypercompliant state wherein the brain parenchyma is unable to hold the pressure exerted by CSF, thereby facilitating passive pooling of CSF and secondary distention of the ventricles. Ventriculomegaly occurs in the absence of altered cilia-generated CSF flow or congenital aqueductal obstruction. Neuroimaging studies in patients with TRIM71 mutations also suggest cortical hypoplasia as the primary physiological factor leading to secondary ventricular dilation and passive pooling of CSF. CONCLUSIONS: We highlight the importance of precisely regulated neural stem cell fate and neurogenesis for maintaining normal brain-CSF biomechanical interactions that limit ventricular expansion. We thus demonstrate that some or potentially many forms of CH are in fact a congenital brain malformation akin to microcephaly with secondarily enlarged ventricles rather than a primary disturbance in CSF circulation.

Объем и разновидности офтальмохирургических вмешательств, выполняемых в детском офтальмологическом отделении, их эффективность

Purpose. To evaluate volume and nosological forms of ophthalmic surgery cases in the pediatric department of the ophthalmology surgery and analyze their effectiveness. Material and methods. A continuous retrospective number of all ophthalmic surgery in the pediatric ophthalmology department of the Khabarovsk branch of the S. Fyodorov Eye Microsurgery Federal State Institution for three years (from January 2019 to December 2021). Results. 5025 children aged from 1 month to 18 years old were operated. Surgical treatment of pathology of oculomotor apparatus was performed in 2304 (45.9%) patients, scleral remodeling in progressive myopia – 1088 (21.7%) people, probing for congenital lacrimal ducts obstruction – 619 (12.3%) children. In 463 (9.2%) children, surgical removal of the chalazion was performed. 166 (3.3%) children were operated for eyelid, conjunctival and orbital tumors. 120 patients (2.4%) underwent surgical revascularization for optic nerve atrophy of various origins. 96 children underwent surgical correction of various congenital eyelid anomalies. During this period, 169 premature babies (3.4%) were under observation in the department. Of these, at threshold stages of retinopathy of prematurity (ROP), 34 patients underwent laser coagulation of avascular areas of retina, 22 patients received intravitreal ranibizumab injection, 14 children with stage 4 or 5 ROP underwent endovitreal intervention of traction retinal detachment. Conclusion. The volume of ophthalmic surgery performed in the pediatric department is quite high, the largest proportions are various methods for eliminating the pathology of oculomotor apparatus and scleral remodeling in progressive myopia. In most cases of strabismus and ptosis surgery, it was possible to achieve complete or partial elimination of pathology. Stabilization of the progressive course of myopia was achieved in 67.9% of cases, threshold stages of ROP – in 91.7%. The high demand of population for surgical treatment of pediatric ophthalmopathology indicates the need for further development and improvement of this area. Key words: pediatric ophthalmology, structure of surgical pathology, main trends of ophthalmic surgery

Factors associated with outcomes in congenital duodenal obstruction: population-based study.

Factors associated with outcomes in congenital duodenal obstruction: population-based study.

Variation in the Expression of Interstitial Cell of Cajal-like Cell (CD117) Across Congenital Pelvic-ureteric Junction Obstruction and its Renal Sonological and Functional Correlation: A Prospective Observational Study.

This study aims to study the variation in the expression of CD117-positive interstitial cells of Cajal-like cells (ICC-LC) across the upper urinary tract region in children presenting with pelvic-ureteric junction obstruction (PUJO) and its association with renal functional and sonological parameters of patients. A prospective observational study was done on 20 children with congenital PUJO who underwent dismembered pyeloplasty. All children underwent renal sonography (anteroposterior pelvic diameter [APPD], pelvicalyceal ratio [P/C ratio], Mid polar renal parenchymal diameter [MPPD]) and functional imaging scan (LLEC scan or DTPA scan). Three specimens were taken intraoperatively from above PUJ, at the level of PUJ, and below PUJ. Those were examined immunohistochemically using CD117 to count ICC-LC using standard criteria. Variation in the expression of CD117-positive ICC-LC was correlated with the abovestated parameters. The number of CD117-positive ICC-LC showed a continuous decreasing trend above downward. P/C ratio and APPD showed a parallel trend with ICC-LC distribution, whereas split renal function (SRF) showed an inverse relationship with the expression of ICC-LC. Children with lesser severity of obstruction (APPD <30 mm and SRF >40%) showed a uniform decreasing trend in the number of CD117-positive ICC-LC across PUJ. Children with more severe obstruction (APPD >30 mm and SRF <40%) showed a decrease in the expression of ICC-LC up to the level of PUJO followed by a sudden relatively increased expression of ICC-LC below the obstruction. The expression of ICC-LC shows a uniformly decreasing trend across obstruction when the severity of obstruction is less. Resurgence in the number of ICC-LC below PUJ in subjects with severe obstruction hints at the emergence of a new pacemaker area below severely blocked PUJ akin to that seen in complete heart block patients and deserves early attention.

Congenital urinary obstruction and renal failure: has fetal ultrasound improved the prognosis?

Fetal ultrasound can identify babies who are at risk of developing renal failure. However, renal damage before birth is difficult to reverse and end‐stage renal failure may not be preventable.

Duodenal Stenosis: A Case Report

Background: Congenital duodenal stenosis in pediatric patients was often underreported due to its non-conspicuous signs and symptoms. Diagnosing duodenal stenosis is often challenging as this disease causes partial intestinal obstruction and thus presents with more indolent and atypical clinical manifestations. This case report aims to describe the atypical case of pediatric duodenal stenosis which presented with recurrent vomiting and poor weight gain as well as highlight some of the diagnostic challenges.&#x0D; Case: A 7-month-old girl was admitted to the emergency room with chief complaint of recurrent vomiting in the last 2 days prior to hospital admission. Patient had a history of recurrent bilious vomiting at the age of 3 days old with a frequency of 3-4 times a day and were admitted to the hospital for 2 weeks. Parents also reported of poor weight gain in the last 3 months. Abdominal X-Ray series showed dilatation of the small intestines immediately after pylorus and stack of coins sign. Esophageal endoscopic evaluation showed signs of severe GERD with a pyloric gap as well as a suspicion of a duodenal web&#x0D; Discussion: Congenital obstruction at the duodenum may occurs due to intrinsic or extrinsic etiology. Failure of duodenal re-canalization during the 8-10th week of embryological development is thought to be the main cause of intrinsic duodenal obstruction (atresia, stenosis or duodenal web). The appearance of clinical manifestation of duodenal stenosis depends on the degree of stenosis itself.&#x0D; Conclusion: Congenital duodenal stenosis may present with atypical presentations in neonates which requires clinicians to be fully aware of this diagnosis to ensure timely therapy. The main management of duodenal stenosis is surgery, however fluid administration, decompressing as well as other supportive treatment are equally crucial to ensure better outcome for the patient.

Outcomes of neonates with congenital duodenal obstruction: A retrospective study

BackgroundCongenital duodenal obstruction (CDO) is a common cause of intestinal obstruction in newborn infants. There is limited information on growth and neurodevelopmental outcomes of infants with CDO. Recent studies have suggested that early commencement of enteral feeds facilitates early attainment of full feeds in surgical and very premature non-surgical infants. We aimed to describe the physical growth and one-year neurodevelopmental outcomes of infants with CDO, and to explore the association between time of commencement of enteral feeds and time to reach full feeds in CDO. MethodsRetrospective study (2002–2019). ResultsA total of 76 infants were included. The median gestational age was 37.2 w (range: 25.7 to 40.8). There were four deaths, not directly related to CDO. The mean Z scores for weight at birth was -0.39 (SD 1.05) vs -1.18 (SD 1.07) at discharge (p<0.0001). The mean Z scores for head circumference at birth was -0.04 (SD 1.21) vs -0.43 (SD 1.23) at discharge (p = 0.021). Adequate catch up growth occurred by one year. The median Development quotient (DQ) on Griffiths Mental Developmental Scales at one year among 41 non-syndromic infants was 100 (IQR: 94 to 107). On multivariable analysis, each day delay in commencing feeds was associated with 6% increase in time to reach full feeds (adjusted and exponentiated beta coefficient: 1.06; 95% CI: 1.02 to 1.09; p = 0.001). ConclusionsInfants with CDO had significant postnatal growth restriction during hospitalisation. Neurodevelopmental outcomes were reassuring. Early commencement of enteral feeds in the postoperative period may facilitate early attainment of full feeds. Level of evidenceLevel IV Prognostic study

Congenital Duodenal Obstruction: National Trends in Management and Outcomes during the Last Quarter of a Century in Norway.

During the last quarter of a century, new surgical techniques in neonates have been introduced, and neonatal intensive care has developed. Few studies have explored the implementation of new techniques and if outcomes in neonates undergoing gastrointestinal surgery have improved in the last decades. Therefore, this study aimed to investigate possible changes in postoperative outcomes and surgical techniques in all neonates operated for congenital duodenal obstruction (CDO) 1995 to 2020 in Norway. This is a national multicenter retrospective study of all neonates undergoing surgery for CDO in Norway from 1995 to 2020. Results from three periods (1995-2003, 2004-2012, and 2013-2020) were compared. The study was approved by the local data protection officers (2020/13386) and (2020/15125). We included 186 patients: 41 in period 1 (1995-2003), 83 in period 2 (2004-2012), and 62 in period 3 (2013-2020). Seventy (38%) neonates had Down syndrome and 104 (62%) had additional malformations/disorders. Birth weight, gender, frequency of Down syndrome, and other malformations/disorders did not differ between the three periods. We observed an increased rate of prenatal diagnosis throughout the study period (p < 0.001). The only change in surgical technique was the increased use of transanastomotic feeding tubes (p < 0.001). Length of stay, postoperative complication rate, days with parenteral nutrition, and 30-day mortality rate were stable over time. Perioperative treatment and postoperative outcomes in neonates with CDO have been surprisingly unchanged during the last quarter of a century. Only an increased rate of prenatal diagnosis and more frequent use of transanastomotic feeding tubes were observed.

CAKUT: A Pediatric and Evolutionary Perspective on the Leading Cause of CKD in Childhood

The global prevalence of chronic kidney disease (CKD) is increasing rapidly, due to increasing environmental stressors through the life cycle. Congenital anomalies of kidney and urinary tract (CAKUT) account for most CKD in children, with a spectrum that can lead to kidney failure from early postnatal to late adult life. A stressed fetal environment can impair nephrogenesis, now recognized as a significant risk factor for the development of adult CKD. Congenital urinary tract obstruction is the leading cause of CKD due to CAKUT and can itself impair nephrogenesis as well as contribute to progressive nephron injury. Early diagnosis by ultrasonography in fetal life by an obstetrician/perinatologist can provide important information for guiding prognosis and future management. This review focuses on the critical role played by the pediatrician in providing timely evaluation and management of the patient from the moment of birth to the transfer to adult care. In addition to genetic factors, vulnerability of the kidney to CKD is a consequence of evolved modulation of nephron number in response to maternal signaling as well as to susceptibility of the nephron to hypoxic and oxidative injury. Future advances in the management of CAKUT will depend on improved biomarkers and imaging techniques.

Genetics of Hirschsprung's disease.

Hirschsprung's disease (HSCR) is a classical model of enteric neuropathy, occurring in approximately 2-2.8 in 10,000 newborns. It is the commonest form of congenital bowel obstruction and is characterized by the absence of enteric ganglia in distal colon. Recent advances in genome-wide association analysis (GWAS) and next generation sequencing (NGS) studies have led to the discovery of a number of new HSCR candidate genes, thereby providing new insights into the genetic architecture and molecular mechanisms of the disease. Altogether, these findings indicated that genetic heterogeneity, variable penetrance and expressivity, and genetic interaction are the pervasive characteristics of HSCR genetics. In this review, we will provide an update on the genetic landscape of HSCR and discuss how the common and rare variants may act together to modulate the phenotypic manifestation. Translating the genetic findings to genetic risk prediction and to optimize clinical outcomes are undoubtedly the ultimate goals for genetic studies on HSCR. From this perspective, we will further discuss the major obstacles in the clinical translation of these latest genetic findings. Lastly, new measures to address these clinical challenges are suggested to advance precision medicine and to develop novel alternative therapies.

Novel qualitative and quantitative ultrasound markers to facilitate prenatal diagnosis of congenital duodenal obstruction

Objective Accurate prenatal diagnosis of congenital duodenal obstruction (CDO) is challenging. We aimed to determine new ultrasound metrics for accurate prenatal diagnosis of fetal CDO. Methods Data pertaining to 46 fetuses with suspected small intestinal obstruction (26 CDO; 16 high jejunal obstructions) were retrospectively analyzed. Prenatal ultrasonographic features including dilated intestinal length, stomach length, maximum intestinal dilatation, ratio of dilated intestinal length at late gestation and dilated stomach length (I/S ratio), and location of distal end of dilated bowel segment relative to spine were compared between CDO and high jejunal obstruction groups. The diagnostic performance of ultrasound indices was evaluated using receiver operating characteristics curve analysis. Results In 25 out of 26 CDO cases, the distal end of the dilated small intestine segment was located on the right side of spine, while that in the high jejunal obstruction group was located on the left side of spine. The dilated intestinal length and I/S ratio in CDO group were significantly smaller than those in high jejunal obstruction group (p < .05). Dilated intestinal length <51 mm or I/S ratio <1 showed high sensitivity (100, 100%) and specificity (96.1, 92.3%) for CDO (area under the curve: 0.995 and 0.988, respectively). There were no significant differences in the AUCs of dilated intestinal length and I/S ratio. Significant correlation of the site of obstruction in CDO with fetal dilated intestinal length and I/S ratio (r = 0.686; 0.660, p < .001, respectively) were noted. Conclusion Location of the distal end of the dilated small intestine segment relative to the spine, dilated intestinal length, and I/S ratio may help differentiate fetal CDO from high jejunal obstruction. The latter two metrics were associated with the site of obstruction in CDO patients.

Fetal intestinal loop dilatation: Follow-up and outcome of a series of 133 consecutive cases (the DILDIG study).

To define the prognostic markers of fetal dilated bowel loops. National non-interventional study of 133 consecutive prenatal observations of dilated loops including ultrasound examinations, complementary laboratory tests, magnetic resonance imaging (MRI), outcomes, and postnatal diagnosis. One hundred twenty seven cases were classified according to outcome: Group 1, very severe (n=43), Group 2, children needing specific care (n=39), and Group 3, healthy children (n=45). Prenatal ultrasound scan suggested duodenal obstruction in 30 cases, small bowel obstruction in 81, colonic obstruction in 11, and diffuse dilatation in 5. Diameter of dilated loops did not significantly differ between the groups. A poor prognosis was significantly associated with duodenal obstruction, genetic anomalies (53% vs. 21.8%), including aneuploidies or CFTR gene mutations and abnormal amniotic fluid biochemistry (86.4% vs. 38.7%). A good prognosis was associated with regression of dilatation and normal MRI. In this study, postnatal outcomes for fetuses with intestinal dilatation were best predicted by assessing the level of obstruction with prenatal ultrasound and MRI, determining the presence of associated malformations, amniotic fluid biochemical and genetic testing, and monitoring for regression of bowel dilatation. These results should help inform future guidelines on the prenatal and neonatal management of congenital intestinal obstruction.

Avaliação do conhecimento dos pediatras e neonatologistas sobre afecções oculares na infância

Objective: The aim was to evaluate the level of knowledge of pediatricians and neonatologists about eye problems in children, their diagnosis and management, using a standardized questionnaire. Methods: A questionnaire with demographic data and questions about ophthalmological knowledge was applied among pediatricians, through the transmission line of the pediatric service of the HC FMRP/USP from January to June 2021. A cross-sectional study was carried out, whose responses were tabulated, and statistical analysis was performed using the Krukal Wallis Test and Fishers Exact Test for comparison between the pre-established groups (pediatric residents, 4 to 9 years, and more than 10 years of practice in pediatrics). Sampling was by convenience. Results: The structured questionnaire was sent to 277 pediatricians. Ninety pediatricians answered the questionnaire and 81.11% were female. As for the time of pediatric practice, 42.22% had more than 10 years. From the 17 questions about ophthalmologic knowledge, correct answers ranged from 6 to 14, and the average score was 58.52%. The questions with the highest error rate were about the management of newborns with ocular discharge and congenital tear obstruction and when a premature child should be evaluated by an ophthalmologist. However, no significant differences were found when comparing the correct answers between the groups (p=0.425) Conclusion: The results suggest a deficiency in ophthalmologic knowledge among the pediatricians interviewed; therefore, continuing education and collaboration programs between ophthalmology and pediatrics disciplines should be developed and reinforced to deepen knowledge on these topics.

P638: Identification of a pathogenic variant in NSDHL in a patient with congenital high airway obstruction (CHAOS) syndrome

P638: Identification of a pathogenic variant in NSDHL in a patient with congenital high airway obstruction (CHAOS) syndrome

Hybrid First-stage Palliation and Other Strategies to Achieve Biventricular Repair in High-Risk Neonates With Complex Heart Anomalies and Aortic Arch Obstruction.

Medical and surgical advances have allowed single-stage total repair in neonates born with complex congenital heart anomalies and aortic arch obstruction. Nonetheless, total repair might be too complex or high risk in certain neonates with demographic, clinical or morphologic risk factors. Alternative management strategies might offer these neonates better outcomes with superior anatomic repair, shorter hospitalization, reduced morbidity, and improved survival. Alternative initial surgical strategies might include aortic arch repair and pulmonary artery band with or without cardiopulmonary bypass, extracardiac repair only and pulmonary artery band, Norwood operation, and hybrid first-stage palliation; all deferring complex biventricular intra-cardiac repair to later stage. The strategy choice should be personalized to each patient, taking into consideration the morphologic and clinical state, and the existent goals of care.

AVALIAÇÃO DO CONHECIMENTO DOS PEDIATRAS E NEONATOLOGISTAS SOBRE AFECÇÕES OCULARES NA INFÂNCIA.

Objective: The aim was to evaluate the level of knowledge of pediatricians and neonatologists about eye problems in children, their diagnosis and management, using a standardized questionnaire. Methods: A questionnaire with demographic data and questions about ophthalmological knowledge was applied among pediatricians, through the transmission line of the pediatric service of the HC FMRP/USP from January to June 2021. A cross-sectional study was carried out, whose responses were tabulated, and statistical analysis was performed using the Krukal Wallis Test and Fishers Exact Test for comparison between the pre-established groups (pediatric residents, 4 to 9 years, and more than 10 years of practice in pediatrics). Sampling was by convenience. Results: The structured questionnaire was sent to 277 pediatricians. Ninety pediatricians answered the questionnaire and 81.11% were female. As for the time of pediatric practice, 42.22% had more than 10 years. From the 17 questions about ophthalmologic knowledge, correct answers ranged from 6 to 14, and the average score was 58.52%. The questions with the highest error rate were about the management of newborns with ocular discharge and congenital tear obstruction and when a premature child should be evaluated by an ophthalmologist. However, no significant differences were found when comparing the correct answers between the groups (p=0.425) Conclusion: The results suggest a deficiency in ophthalmologic knowledge among the pediatricians interviewed; therefore, continuing education and collaboration programs between ophthalmology and pediatrics disciplines should be developed and reinforced to deepen knowledge on these topics.

Avaliação do conhecimento dos pediatras e neonatologistas sobre afecções oculares na infância

OBJECTIVE: The aim was to evaluate the level of knowledge of pediatricians and neonatologists about eye problems in children, their diagnosis and management, using a standardized questionnaire. METHODS: A questionnaire with demographic data and questions about ophthalmological knowledge was applied among pediatricians, through the transmission line of the pediatric service of the HC FMRP/USP from January to June 2021. A cross-sectional study was carried out, whose responses were tabulated, and statistical analysis was performed using the Krukal Wallis Test and Fishers Exact Test for comparison between the pre-established groups (pediatric residents, 4 to 9 years, and more than 10 years of practice in pediatrics). Sampling was by convenience. RESULTS: The structured questionnaire was sent to 277 pediatricians. Ninety pediatricians answered the questionnaire and 81.11% were female. As for the time of pediatric practice, 42.22% had more than 10 years. From the 17 questions about ophthalmologic knowledge, correct answers ranged from 6 to 14, and the average score was 58.52%. The questions with the highest error rate were about the management of newborns with ocular discharge and congenital tear obstruction and when a premature child should be evaluated by an ophthalmologist. However, no significant differences were found when comparing the correct answers between the groups (p=0.425) CONCLUSION: The results suggest a deficiency in ophthalmologic knowledge among the pediatricians interviewed; therefore, continuing education and collaboration programs between ophthalmology and pediatrics disciplines should be developed and reinforced to deepen knowledge on these topics.

TREATMENT OF CONGENITAL DUODENAL OBSTRUCTION: FROM OPEN TO LAPAROSCOPIC APPROACH FOR DUODENO-DUODENAL ANASTOMOSIS.

Conginental duodenal obstruction is a relatively rare malformation. Laparoscopic operation for this condition was described for the first time in 2001, but more than 20 years later, there is still debate over the preferred method of surgical correction. We believe that laparoscopic correction of conginental duodenal obstruction is a safe and feasible method and can be used in premature infants with low body weight. Materials and Methods: From September 2017 to December 2021, 27 children with conginental duodenal obstruction were treated in our department. We were able to identify the diagnosis in 17 children during the antenatal period, while plain X-ray confirmed postnatal diagnosis. In doubtful cases the contrast fluoroscopy was performed. Four children underwent open correction of the defect via a circumbilical approach, while laparoscopic duodeno-duodenal anastomosis using the Kimura technique was performed in the remaining 23 children. Results: Intraoperative complication in the form of duct injury was observed in 1 patient with an atypically located Wirsung duct. In the postoperative period, anastomotic failure was noted in 2 children, and perforation of the duodenum was detected in 2 patients. The mortality rate comprised 26%, which was partly attributed to severe concomitant pathologies. The use of prolonged epidural analgesia in combination with laparoscopic surgery provided early weaning from mechanical ventilation and transfer from the intensive care unit. Enteral feeding was initiated on postoperative day 5, and the average length of hospital stay was 29±10.5 days. Conclusion: There are no limitations to performing laparoscopic correction of congenital duodenal obstruction. When there are accompanying congenital defects, minimally invasive technology allows to perform combined operations on organs of the thoracic and abdominal cavity, which reduces the overall surgical time. In combination with prolonged epidural analgesia, laparoscopic technique reduces the length of stay in the intensive care unit and the need for parenteral nutrition, which ultimately lowers the risk of inflammatory complications and treatment costs.

Evaluation of prenatal and postnatal ultrasonography for the diagnosis of fetal double bubble sign.

Congenital duodenal obstruction (CDO) is commonly detected antenatally through the presence of the "double bubble" sign on prenatal ultrasound, denoting dilatation of the stomach and duodenum. Subsequent postnatal ultrasonography plays a pivotal role in determining the causes of obstruction, thereby informing surgical strategies and neonatal management. The aim of this study was to investigate the diagnostic accuracy of postnatal ultrasonography in comparison to that of prenatal ultrasound and surgical findings in a cohort of 43 patients with fetal double bubble sign. A total of 43 patients, comprising 24 males and 19 females, who exhibited double bubble sign on prenatal ultrasound were subjected to postnatal ultrasound assessment at a tertiary care facility during the 2018-2023 period. The accuracy of both pre-and postnatal ultrasonography in the identification and diagnosis of CDO, as well as its underlying causes, was compared to that of the established gold standard of surgical findings. The accuracy rates for prenatal and postnatal ultrasonic diagnosis of CDO were 97.7% (42/43) and 100% (42/42), respectively. In terms of etiological diagnosis, prenatal and postnatal ultrasound correctly identified the causes of obstruction in 45.2% (19/42) and 81.0% (34/42) of cases, respectively, as confirmed by surgical intervention. The presence of the prenatal double bubble sign serves as a highly reliable indicator for CDO. Additionally, postnatal ultrasonography proved to be a valuable tool in refining the diagnosis and determining the underlying causes of obstruction in neonates.

Using beta regression modeling in medical sciences: a comparative study

Beta regression (BR) models provide an adequate approach for modeling continuous outcomes of limited intervals (0, 1). The BR model assumes that the dependent variable follows a beta distribution and that its mean is affiliated to a set of exploratory variables through a linear predictor known as coefficients and link function. The BR model also includes a dispersion parameter. This paper describes the BR model along with its properties. Furthermore, the comparison between different link functions of the BR model is conducted through a medical real-life application to laparoscopic surgical operations aiming to widen congenital obstruction in the connection between the kidney and ureter, a condition called ureteropelvic junction obstruction (UJO).