Significant Hypoplasia Research Articles

Cornelia de Lange Syndrome: Expanding the Neuropathological Spectrum and Clinical Correlations

Objectives Reporting new neuropathological findings and clinicopathological correlations in Cornelia de Lange syndrome. Methods and results Cornelia de Lange syndrome has received much attention for its genetics, biochemistry, clinical approach and management, but neuropathological studies are extremely rare. Diffuse hypoplasia of the entire brain, mainly affecting the frontal cortex and, less frequently, the cerebellum, has long been the paradigm for neuropathological findings in rare affected patients. This comprehensive neuropathological study of an affected newborn demonstrates nerve cell heterotopies, poor periventricular matrix and significant hypoplasia of both hippocampi, while Golgi staining of cerebellar tissue samples shows features of nerve cell immaturity. Conclusions The importance of Cornelia de Lange syndrome as a cohesinopathy and some new neuropathological findings provide an opportunity to discuss and establish interesting clinicopathological correlations, especially with regard to the global intellectual disability of these patients.

Speech and Language Development, Hearing, and Feeding in Patients With Genetically Confirmed Crouzon Syndrome With Acanthosis Nigricans: A 36-Year Longitudinal Retrospective Review of Patients at the Oxford Craniofacial Unit.

Crouzon syndrome with acanthosis nigricans (CAN) is caused by the specific mutation c.1172C>A (p.Ala391Glu) in the fibroblast growth factor receptor 3 gene, and has an estimated prevalence of 1:1,000,000 births. Most cases occur de novo; however, autosomal dominant inheritance may occur. The clinical presentation typically includes craniosynostosis, midface and maxillary hypoplasia, choanal atresia/stenosis, hydrocephalus, and intracranial hypertension. Patients develop acanthosis nigricans, a hyperkeratotic skin disorder. The authors present the first known study to investigate the speech, language, hearing, and feeding of patients with CAN. A retrospective case-note review of patients with a genetically confirmed diagnosis of CAN attending the Oxford Craniofacial Unit during a 36-year period (1987-2023) was undertaken. Participants were 6 patients with genetically-confirmed CAN (5 females, 1 male), all cases arose de novo. All patients had craniosynostosis (n = 5/6 multisuture synostosis, n = 1/6 left unicoronal synostosis). Hydrocephalus was managed through ventriculoperitoneal shunt in 67% (n = 4/6) of patients, and 67% (n = 4/6) had a Chiari 1 malformation. Patients had a complex, multifactorial feeding history complicated by choanal atresia/stenosis (100%; n = 6/6), and significant midface hypoplasia. All patients required airway management through tracheostomy (83%; n = 5/6); and/or continuous positive airway pressure (67%; n = 4/6). All patients underwent adenotonsillectomy (100%; n = 6/6). Initial failure to thrive, low weight, and/or height were seen in 100% (n = 6/6) patients; 80% (n = 4/5) had reflux; 100% (n = 6/6) had nasogastric, or percutaneous endoscopic gastrostomy based feeding during their treatment journey. All patients had hearing loss (100%; n = 6/6). Early communication difficulties were common: receptive language disorder (50%; n = 3/6); expressive language disorder (50%; n = 3/6); and speech sound disorder in 50% (n = 3/6)-necessitating the use of Makaton in 80% of patients (n = 3/5). Patients with CAN experience significant respiratory, neurological, and structural obstacles to hearing, speech, language, and feeding. The authors present a recommended pathway for management to support patients in these domains.

Long-Term Outcomes of Ascending Sliding Arch Aortoplasty.

Background: Coarctation of the aorta can be associated with significant hypoplasia of the aortic arch. In contrast to patch aortoplasty, ascending sliding arch aortoplasty uses viable autologous tissue for potential growth in children. We reviewed the mid- to long-term outcomes of this technique. Methods: Between 2002 and 2023, 28 patients underwent ascending sliding arch aortoplasty for the patients with coarctation of the aorta (n = 22) and interrupted aortic arch (n = 2). Four patients underwent previous surgical coarctation repair at other institutions. The median patient age and body weight were 28.5 months (3 weeks to 15.6 years) and 13.4 kg (3.7-70 kg), respectively. Results: Although one patient had a recurrent nerve injury postoperatively, there were no other major morbidities or mortalities. The last follow-up echocardiography demonstrated that the mean peak velocity improved from 3.9 ± 0.6 to 0.9 ± 0.8 m/s, and the pressure gradient improved from 63.6 ± 21.5 to 7.1 ± 7.7 mm Hg. The postoperative diameters of the ascending aorta, proximal arch, distal arch, and isthmus all increased significantly. The mean postoperative length of stay was 5.9 ± 2.1 days, and the median follow-up time was 7.3 years (10 days to 20.5 years). No reoperation or catheterization-based intervention was performed for residual coarctation. Conclusions: Ascending sliding arch aortoplasty is safe and effective for treating coarctation of the aorta with aortic arch hypoplasia. This technique is applicable for children ranging in size from neonates to older children (or adolescents), recurrent coarctation cases, and provides complete relief of narrowing by utilizing viable native aortic tissue.

Defining the Spectrum of Hypoplastic Left Heart Syndrome (HLHS).

The 2021 International Paediatric and Congenital Cardiac Code and the Eleventh Revision of the International Classification of Diseases provide the following definition for hypoplastic left heart syndrome (HLHS): "Hypoplastic left heart syndrome (HLHS) is defined as a spectrum of congenital cardiovascular malformations with normally aligned great arteries without a common atrioventricular junction, characterized by underdevelopment of the left heart with significant hypoplasia of the left ventricle including atresia, stenosis, or hypoplasia of the aortic or mitral valve, or both valves, and hypoplasia of the ascending aorta and aortic arch." Although HLHS with intact ventricular septum (HLHS + IVS) and HLHS with ventricular septal defect (HLHS + VSD) are different cardiac phenotypes, both of these lesions are part of the spectrum of HLHS.

Decreased Expression of Pulmonary Homeobox NKX2.1 and Surfactant Protein C in Developing Lungs That Over-Express Receptors for Advanced Glycation End-Products (RAGE).

Receptors for advanced glycation end-products (RAGE) are multi-ligand cell surface receptors of the immunoglobin superfamily prominently expressed by lung epithelium. Previous experiments demonstrated that over-expression of RAGE by murine alveolar epithelium throughout embryonic development causes neonatal lethality coincident with significant lung hypoplasia. In the current study, we evaluated the expression of NKX2.1 (also referred to as TTF-1), a homeodomain-containing transcription factor critical for branching morphogenesis, in mice that differentially expressed RAGE. We also contextualized NKX2.1 expression with the abundance of FoxA2, a winged double helix DNA binding protein that influences respiratory epithelial cell differentiation and surfactant protein expression. Conditional RAGE over-expression was induced in mouse lung throughout gestation (embryonic day E0-18.5), as well as during the critical saccular period of development (E15.5-18.5), and analyses were conducted at E18.5. Histology revealed markedly less lung parenchyma beginning in the canalicular stage of lung development and continuing throughout the saccular period. We discovered consistently decreased expression of both NKX2.1 and FoxA2 in lungs from transgenic (TG) mice compared to littermate controls. We also observed diminished surfactant protein C in TG mice, suggesting possible hindered differentiation and/or proliferation of alveolar epithelial cells under the genetic control of these two critical transcription factors. These results demonstrate that RAGE must be specifically regulated during lung formation. Perturbation of epithelial cell differentiation culminating in respiratory distress and perinatal lethality may coincide with elevated RAGE expression in the lung parenchyma.

Anesthetic considerations in an infant with femoral hypoplasia‐unusual facies syndrome and Pierre Robin sequence: A case report

Key Clinical MessageFemoral hypoplasia‐unusual facies syndrome is a rare condition of unknown etiology. The phenotype consists of significant femoral hypoplasia with characteristic facial malformations that often overlap with findings seen in patients with Pierre Robin sequence. Anesthesia providers must prepare for difficult intravenous access, difficult airway management, and uncertainties with regional anesthesia.AbstractFemoral hypoplasia‐unusual facies syndrome (FHUFS) or femoral facial syndrome is a rare and sporadic condition of unknown etiology. The phenotype consists of significant femoral hypoplasia with characteristic facial malformations that often overlap with findings seen in patients with Pierre Robin sequence. FHUFS is known to cause challenges with anesthesia, including difficulty with endotracheal intubation. Anesthesia providers must be aware of the possible coexistence of FHUFS and Pierre Robin sequence. They need to prepare for difficult intravenous access, difficult airway management, and uncertainties with regional anesthesia.

Fetal pulmonary valvuloplasty for pulmonary atresia with intact ventricular septum: a single-center clinical experience.

Fetal pulmonary valvuloplasty for pulmonary atresia with intact ventricular septum: a single-center clinical experience.

Abstract Number: LBA15 Transient Ischemic Attack Uncovering An Absent ICA

Introduction Absence of the Internal Carotid Artery (ICA) is a rare cerebrovascular anomaly signified by agenesis, aplasia, or hypoplasia of the ICA and its’ bony canal. Agenesis refers to complete absence whereas aplasia refers to some partial remanent of the ICA or the carotid canal however, these terms are often used interchangeably. There are 6 types of ICA agenesis/aplasia of which type A consists of collateral flow supplied to the MCA via the P‐comm and ACA via the A‐comm. The prevalence of such a condition is reported at around .01% of the population. Patients are usually asymptomatic due to robust collaterals but, in some cases, can present with focal neurologic deficits. Here, we present a case of a patient who endured a transient ischemic attack and was subsequently found to have type A Right ICA aplasia on cerebrovascular imaging. Methods Case Report Results A 24‐year‐old Right‐handed Female with no past medical history except for tobacco use presented with transient left arm monoparesis. The patient had received chiropractic treatment involving hyperextension of her neck to the left just prior to symptom onset which transiently caused her left arm to become plegic and she resolved back to her neurologic baseline within 10 minutes. Neurologic exam was normal and non‐contrast head CT was negative however, demonstrated significant hypoplasia of the right carotid canal (Figure 1‐A). Contrast enhanced CT Angiogram of the head and neck demonstrated lack of contrast opacification of the Right Internal Carotid artery with absent Right carotid bulb and opacification of only the Right ECA (Figure 1‐B). MRI of the brain did not demonstrate any acute infarction. Gadolinium enhanced MRA of the Head and Neck confirmed absence of the Right internal carotid (Figure 2‐A) with prominent Right P‐comm and absent Right A1 segment (Figure 2‐B). Due to this variant anatomy, the postulated mechanism of patient’s TIA was thought to be related to transiently decreased cerebral perfusion caused by partial mechanical compression of her vertebral arteries asymmetrically affecting the Right MCA distribution due to sole supply from the Right posterior communicating artery. Conclusions This case illustrates a fascinating variation from normal embryologic angiogenesis and highlights the importance of collateral blood flow through the circle of Willis in patient’s with congenitally absent internal carotid arteries. Particularly, this patient’s presentation demonstrates the risk that vascular compromise of posterior circulation vessels may play in patients with Type A ICA agenesis/aplasia and their subsequent risk of incurring transient ischemic events.

RF26 | PSAT109 The Prevalence of Abnormalities in Cranial MRIs in Children with Short Stature Prior to Growth Hormone Therapy

Abstract Background MRIs of the brain in patients with short stature have shown a number of abnormalities. Some of these radiological findings can have clinical significance. Here we have looked at MRI results in such a population. Objective To review the value and significance of the prevalence of all abnormal MRI findings of children with short stature who are to undergo growth hormone therapy (GHT). Materials and methods This study involved a retrospective review of MRI findings in all children prescribed GHT within a pediatric health network's database from Jan 2020 to Aug 2021. Post-gadolinium contrast enhanced brain and pituitary MRIs utilizing 2 mm slices were used to calculate pituitary volume. Pituitary volume was calculated using the ellipsoid formula (LxWxH/2). Pediatric patients diagnosed with non-acquired GHD or ISS, with MRIs having been performed between Jan 2020 and Aug 2021 and having been prescribed GHT by Aug 2021 were included in this study. Patients who experienced other endocrine abnormalities such as SGA, Turner Syndrome, and Noonan Syndrome were excluded. Patients with obstruction of sellar and parasellar religion due to movement artifacts or magnetic interference on their MRIs were also excluded. Results Of one hundred and twelve patients found, eighty one met criteria for inclusion in this study. Of the eighty one MRIs reviewed, twenty eight children, 34.6%, had normal pituitary anatomy and fifty three, 65.4%, had a pituitary abnormality. Out of the fifty three with a pituitary abnormality, forty three subjects, 81.1%, were determined to have a small pituitary volume, including significant pituitary hypoplasia. Ten subjects (18.9%) had an enlarged pituitary volume (pituitary hyperplasia). Of these ten patients who had an enlarged pituitary volume, eight were pubertal (80%). Nine children with a pituitary abnormality (16.9%) had additional structural anomalies on their MRIs. One had a small left frontal developmental venous anomaly. Two had Rathke's cleft cysts. Two had pars intermedia cysts. One had a small right parietal developmental venous anomaly. One had a small left parietal developmental venous anomaly. One had a left cerebellar tonsillar ectopia bordering on chiari malformation (.5 mm away on the coronal plane). One had a small lobulation (semi-bulbous projection) of the anterior pituitary gland, superior and anterior to the infundibular stalk. Conclusion Prevalence of brain abnormalities in children with short stature who are to undergo GHT is significant and warrants MRI evaluations in these subjects. Presentation: Saturday, June 11, 2022 1:00 p.m. - 3:00 p.m., Monday, June 13, 2022 12:58 p.m. - 1:03 p.m.

The interplay between prenatal liver growth and lung development in congenital diaphragmatic hernia.

ObjectiveLiver herniation is a known risk factor for increased severity in CDH and is associated with clinically significant pulmonary hypoplasia and pulmonary hypertension. Better studies are needed to understand the growth of the herniated liver compared to the liver that remains in the abdomen and how this liver growth then affects lung development. Serial hi-resolution fetal MRI enables characterization of liver growth throughout gestation and examination of macroscopic features that may regulate liver growth. Here, we hypothesized that the nature of liver herniation affects liver growth and, in turn, affects lung growth.MethodsClinical data were retrospectively collected from consecutive cases of prenatally diagnosed isolated left-sided or right-sided CDH from June 2006 to August 2021. Only those cases with MRI lung volumetry for both mid-gestation and late-gestation time points were recruited for analysis. Cases with fetal chromosomal abnormalities and other major structural abnormalities were excluded. Fractional liver volume and liver growth was indexed to estimated fetal weight and compared to lung growth.ResultsData was collected from 28 fetuses with a left liver-down CDH (LLD), 37 left liver-up CDH (LLU) and 9 right liver-up CDH (RLU). Overall, RLU fetuses had greater overall and fractional (intra-thoracic vs. intra-abdominal) liver growth when compared to LLD and LLU fetuses. Additionally, intra-thoracic liver growth was consistently slower than intra-abdominal liver growth for either right- or left-sided CDH. When the liver was not herniated, a positive correlation was seen between liver growth and lung growth. However, when the liver was herniated above the diaphragm, this positive correlation was lost.ConclusionRight-sided CDH fetuses exhibit greater liver growth compared to left-sided CDH. Liver herniation disrupts the normal positive correlation between liver and lung growth that is seen when the liver is entirely within the abdomen.

Hypoplastic Left Ventricle: Hypoplastic Left Heart Complex.

Hypoplastic left heart syndrome (HLHS) without intrinsic valvar stenosis or atresia is synonymous with the term hypoplastic left heart complex (HLHC) and is defined as a cardiac malformation at the milder end of the spectrum of HLHS with normally aligned great arteries without a common atrioventricular junction, characterized by underdevelopment of the left heart with significant hypoplasia of the left ventricle and hypoplasia of the aortic or mitral valve, or both valves, in the absence of intrinsic valvar stenosis or atresia, and with hypoplasia of the ascending aorta and aortic arch. This article describes the definitions, nomenclature, and classification of HLHC; the indications and contraindications for biventricular repair of HLHC; the surgical treatment of HLHC; and the associated outcomes.

Hypoplastic Left Heart Syndrome: Definition, Morphology, and Classification.

This manuscript will provide information about hypoplastic left heart syndrome (HLHS) and related malformations, including definitions, morphology, and classification, based on the 2021 International Paediatric and Congenital Cardiac Code (IPCCC) and the Eleventh Revision of the International Classification of Diseases (ICD-11). HLHS is defined as "a spectrum of congenital cardiovascular malformations with normally aligned great arteries without a common atrioventricular junction, characterized by underdevelopment of the left heart with significant hypoplasia of the left ventricle including atresia, stenosis, or hypoplasia of the aortic or mitral valve, or both valves, and hypoplasia of the ascending aorta and aortic arch." Functionally univentricular heart is defined as "a spectrum of congenital cardiac malformations in which the ventricular mass may not readily lend itself to partitioning that commits one ventricular pump to the systemic circulation, and another to the pulmonary circulation." The Norwood operation is synonymous with the term "Norwood (Stage 1)" and is defined as (1) creation of an aortopulmonary connection and neoaortic arch construction resulting in univentricular physiology and (2) creation of a controlled source of pulmonary blood flow with a calibrated systemic-to-pulmonary artery shunt, a right ventricle to pulmonary artery conduit, or rarely, a cavopulmonary connection. The goals of the Norwood (Stage 1) Operation are creation of (1) unobstructed systemic blood flow via aortopulmonary connection and neoaortic arch construction, (2) unobstructed coronary blood flow, (3) unobstructed flow across the atrial septum, and (4) controlled pulmonary blood flow.

Embryonic Over‐Expression Of RAGE In Mouse Lung Modulates Thyroid Transcription Factor (TTF)‐1 And Surfactant Expression

Receptors for advanced glycation end‐products (RAGE) are multi‐ligand cell surface receptors of the immunoglobin superfamily prominently expressed by lung epithelium. Previous experiments demonstrate that over‐expression of RAGE by murine alveolar epithelium throughout embryonic development causes neonatal lethality coincident with significant lung hypoplasia. In the current study, we evaluated the expression of TTF‐1, a homeodomain‐containing transcription factor critical for branching morphogeneis, in mice that differentially expressed RAGE. We also contexualized TTF‐1 expression with the abundance of FoxA2, a winged double helix DNA binding protein that influences respiratory epithelial cell differentiation, and surfactant proteins. Conditional RAGE over‐expression was induced in mice throughout gestation (embryonic day (E)0‐18.5) as well as during the critical saccular period (E15.5‐18.5) of development and analyses were conducted on E18.5 lung tissue. Histology revealed marked loss of lung tissue beginning in the canalicular stage of lung development and continuing throughout the saccular period. We discovered consistently decreased expression for both TTF‐1 and FoxA2 in lungs from TG mice compared to age‐matched controls. We also clarified diminished surfactant protein abundance in TG mice, suggesting possible hindered differentiation and/or proliferation of alveolar epithelial cells under the genetic control of these two critical transcription factors. These results demonstrate that RAGE must be specifically regulated during lung formation and that perturbation of epithelial cell differentiation culminating in respiratory distress and perinatal lethality may coincide with elevated RAGE expression in the lung parenchyma.

Orbital and Periorbital Dysmorphology in Untreated Pfeiffer Syndrome.

Visual impairment secondary to orbital and periorbital dysmorphology is frequent in Pfeiffer syndrome patients. The etiopathogenesis of this aberrancy, however, remains unclear. Untreated Pfeiffer syndrome patients (n = 31) and normal control subjects (n = 43) were compared. Craniometric and volumetric analyses related to the orbital and periorbital anatomy were performed using Materialise (Leuven, Belgium) software. Overall, orbital cavity volume of Pfeiffer patients is reduced by 28 percent (p < 0.001), compared to normal, starting before 3 months of age (p = 0.004). Globe volume was diminished by 10 percent (p = 0.041) before 3 months of age, yet tended to catch up thereafter. However, the retrobulbar soft-tissue volume remained smaller beyond 1 year of age (17 percent, p = 0.003). Globe volume projection beyond the bony orbit increased in all observed ages (82 percent, p < 0.001). The volumes of sphenoid bone, maxilla, and mandible proportionately were restricted by 24 to 25 percent (p = 0.003 to 0.035) before 3 months of age. The volume of maxilla and mandible gradually approximate normal; however, the sphenoid bone volume in Pfeiffer patients remains less than normal (p = 0.002) into childhood. The anteroposterior length of both the zygoma and the maxilla was reduced by 14 percent (p < 0.001). Anterior positioning of the zygoma is less by 23 percent (p < 0.001) in Pfeiffer patients overall, with anterior positioning of maxilla reduced similarly by 23 percent (p < 0.001). Pfeiffer syndrome patients develop decreased retrobulbar soft-tissue and globe volume, along with a restricted orbital cavity volume in infancy. Significant hypoplasia of the sphenoid bone is associated with more severe central facial (maxilla) retrusion, compared to lateral facial structures (zygoma). Risk, II.

Improving Esthetic and Functional Outcomes of Severe Habsburg Jaw Using Modified Mandibular C-Osteotomies: A Case Report and Review of Literature

The hypoplastic mandible results in facial convergence and pseudo-prognathism. We present a patient with significant maxillary hypoplasia in both the vertical and sagittal dimensions resulting in a reverse occlusal plane. Given the significant maxillary movements required, particularly clockwise rotation, more traditional mandibular osteotomies resulted in an unsatisfactory result. A modified version to the classic “C” osteotomy with the use of surgical planning and cutting guides was performed. A review of the literature on this rarely discussed ramus osteotomy is also presented.

A novel surgical toxicological-free model of diaphragmatic hernia in fetal rats.

Teratogen-induced congenital diaphragmatic hernia (CDH) rat models are commonly used to study the pathophysiology. We have created a new and reliable surgically induced diaphragmatic hernia (DH) model to obtain a purely mechanical DH rat model, and avoid the confounding teratogen-induced effects on the lung development. Fetal DH was surgically created on fetuses at E18.5 and harvested at E21.5 in rats. Four groups were evaluated (n = 16): control (CONT), control exposed to Nitrofen (CONT NIT), DH surgically created (DH SURG), and CDH Nitrofen (CDH NIT). Body weight, total lung weights, and their ratio (BW, TLW, and TLBR) were compared. Air space (AS), parenchyma (PA), total protein, and DNA contents were measured to verify lung hypoplasia. Medial wall thickness (MWT) of pulmonary arterioles was also analyzed. DH SURG showed significant hypoplasia (decreased in total protein and DNA) vs CONT (p < 0.05); DH SURG vs CDH NIT were similar in TLW and TLBR. DH SURG has less AS than CONT (p < 0.05) and similar PA compared to CONT NIT and CDH NIT, MWT were similarly increased in CONT NIT, DH SURG, and CDH NIT. This novel surgical model generates fetal lung hypoplasia contributing to the study of the mechanical compression effect on fetal lung development in DH. There is a critical need to develop a surgical model in rat to complement the findings of the well-known Nitrofen-induced CDH model. This experimental study is pioneer and can help to understand better the CDH pathophysiological changes caused by herniated abdominal viscera compression against the lung during the final stage of gestation in CDH fetuses, and also to develop more efficient treatments in near future.

Prevalence of Dental Anomalies in Patients With Unilateral Cleft Lip and Alveolus Treated With Gingivoperiosteoplasty.

To compare the prevalence of dental malformations and agenesis in patients who received or did not receive gingivoperiosteoplasty (GPP). Retrospective cohort study. Review of patients born January 1, 2000, to December 31, 2007, with unilateral cleft lip and alveolus, with or without clefting of the secondary palate, who received GPP and/or secondary alveolar bone grafting (ABG). Patients were included if they had clinical images and dental radiographs available at ages 5 to 9 and 10 to 12 years. Ninety-four patients met the inclusion criteria; 46 treated with GPP, and 48 who did not receive GPP. Records were assessed for supernumerary, missing, and malformed teeth by a blinded examiner, and prevalence compared between groups using χ2 tests. Cleft side lateral incisors were absent in 54% of GPP patients, compared to 50% in the no-GPP group. Two patients in the GPP group and 1 in the no-GPP group had supernumerary lateral incisors. Most lateral incisors were undersized or peg shaped in both the no-GPP (83.3%) and GPP (71.4%) groups. In the GPP group, 5 (10.9%) patients exhibited central incisor agenesis, and 3 had significant hypoplasia. In the no-GPP group, 4 (8.3%) patients exhibited central incisor agenesis, and 5 (10.5%) significant hypoplasia. These differences were not statistically significant. Gingivoperiosteoplasty was not associated with increased prevalence of dental malformation or agenesis. When performed appropriately, GPP is a safe treatment technique that does not increase the risk of dental anomalies.

Use of aortic arch measurements in evaluating significant arch hypoplasia in neonates with coarctation

BackgroundSurgical repair for neonatal arch hypoplasia with coarctation can be performed by a sternotomy or thoracotomy. ObjectivesThis study retrospectively investigates the use of pre-surgical absolute aortic arch measurements in guiding the optimal approach for neonates with coarctation and aortic arch hypoplasia. MethodsPatients ≤ 30 days old who underwent coarctation repair via a median sternotomy or lateral thoracotomy between January 2000 and July 2018 were retrospectively reviewed. Neonates requiring intracardiac surgery were excluded. Specific aortic arch measurements were obtained and 3 ratios calculated: distal transverse arch diameter/carotid artery diameter (DT/CA), distal transverse arch diameter/distance from the carotid to subclavian artery (CSA) and isthmus diameter/descending aorta diameter (I/D). ResultsOf 118 patients, 65 had a lateral thoracotomy and 53 had a median sternotomy. Distal transverse arch, the carotid artery and isthmus diameters correlated with surgical approach. The DT/CA ratio was statistically significant with an ROC curve (p < 0.0001; AUC 0.761) identifying a ratio of 0.9 (sensitivity 91%, specificity 32%) or less as indicative of aortic arch hypoplasia which is likely best suited for a median sternotomy repair. Reintervention rates were similar for both approaches overall and within the first 6 months of operation. ConclusionIn neonates with coarctation, pre-surgical aortic arch measurements and ratios can be utilized to identify aortic arch hypoplasia and guide surgical approach. In our institution, neonates with a DT/CA ratio of 0.9 or less routinely underwent arch reconstruction by a median sternotomy. Re-intervention rates in the median sternotomy and lateral thoracotomy groups were comparable.

Right Ventricular Outflow Tract Stenting as Palliation of Critical Tetralogy of Fallot: Techniques and Results

Background. Despite current trends toward early primary repair, the surgical systemic-to-pulmonary shunt is still considered the first-choice palliation in patients with critical tetralogy of Fallot (TOF) and duct-dependent pulmonary circulation unsuitable for primary repair. However, stenting of the right ventricular outflow tract (RVOT) is nowadays emerging as an effective alternative to surgical palliation in selected patients. Methods and results. RVOT stenting is usually performed from a venous route, either femoral or, in selected cases, the right internal jugular vein. Less frequently, mostly in pulmonary infundibular/valvar atresia, this procedure can be performed using a hybrid surgical/interventional approach by surgical exposure of the RVOT, puncture of the atretic valve, and stent deployment under direct vision. The size and type of the most appropriate stent may be chosen, based on ultrasound measurements of the RVOT, to cover the right ventricular infundibulum completely and, at the same time, sparing the pulmonary valve, unless significant pulmonary valve annulus hypoplasia and/or supra-valvular stenosis is a significant component of the obstruction. In the large series so far published, early mortality of RVOT stenting is less than 2%, comparing favourably with either Blalock-Thomas-Taussig shunt or early primary repair. In addition, morbidity and clinical sequelae of this approach do not significantly differ from surgical palliation, even if RVOT stenting shows lesser durability and a higher rate of trans-catheter re-interventions over a mid-term follow-up. Finally, similar but more balanced pulmonary artery growth than surgical palliation following RVOT stenting is reported over a mid-term follow-up. Conclusions. RVOT stenting is a technically feasible, well-tolerated, and effective palliation in critical TOF. This approach is cost-effective with respect to surgical palliation either in high-risk neonates or whenever a short-term pulmonary blood flow source is anticipated due to the early surgical repair. It effectively increases pulmonary blood flow, improves arterial saturation, and promotes balanced pulmonary artery growth over a mid-term follow-up.

3D morphometric quantification of maxillae and defects for patients with unilateral cleft palate via deep learning-based CBCT image auto-segmentation.

This study aimed to quantify the 3D asymmetry of the maxilla in patients with unilateral cleft lip and palate (UCP) and investigate the defect factors responsible for the variability of the maxilla on the cleft side using a deep-learning-based CBCT image segmentation protocol. Cone beam computed tomography (CBCT) images of 60 patients with UCP were acquired. The samples in this study consisted of 39 males and 21 females, with a mean age of 11.52years (SD=3.27years; range of 8-18years). The deep-learning-based protocol was used to segment the maxilla and defect initially, followed by manual refinement. Paired t-tests were performed to characterize the maxillary asymmetry. A multiple linear regression was carried out to investigate the relationship between the defect parameters and those of the cleft side of the maxilla. The cleft side of the maxilla demonstrated a significant decrease in maxillary volume and length as well as alveolar length, anterior width, posterior width, anterior height and posterior height. A significant increase in maxillary anterior width was demonstrated on the cleft side of the maxilla. There was a close relationship between the defect parameters and those of the cleft side of the maxilla. Based on the 3D volumetric segmentations, significant hypoplasia of the maxilla on the cleft side existed in the pyriform aperture and alveolar crest area near the defect. The defect structures appeared to contribute to the variability of the maxilla on the cleft side.