Carolina V. Guimaraes

Relative rather than absolute macroglossia in patients with Down syndrome: implications for treatment of obstructive sleep apnea

BackgroundChildren with Down syndrome are described as having macroglossia as well as midface hypoplasia. We reviewed anatomic parameters on MRI to determine whether adolescents with Down syndrome have true macroglossia or relatively large tongues compared to the small size of their oral cavity. This has implications for the treatment of obstructive sleep apnea, which occurs at a relatively high rate among patients with Down syndrome.ObjectiveTo determine whether adolescents with Down syndrome have relative rather than true macroglossia.Materials and methodsOn sagittal and axial MR images, parameters for tongue size (area in sagittal midline), the bony craniofacial confines of the retroglossal pharynx (distance between the mandibular rami and distance between the posterior aspect of the mental mandible and the anterior aspect of the spine), and the size of the tongue relative to the craniofacial bony parameters [tongue area/(transverse diameter × anterior-to-posterior diameter)] were compared between 16 patients with Down syndrome and 16 age- and gender-matched controls.ResultsThe tongue area was significantly smaller in patients with Down syndrome (2,432xa0mm2) than in the control patients (2,767xa0mm2; P=0.02). The craniofacial bony parameters were also smaller in patients with Down syndrome than in the controls (left–right 69.8 vs. 80.1xa0mm, P<0.001; anterior–posterior 64.2 vs. 74.9xa0mm, P<0.001). However, the size of the tongue relative to the craniofacial parameters was larger in the patients with Down syndrome (0.54) than in the controls (0.46; P<0.001).ConclusionChildren with Down syndrome do not have true macroglossia but have relatively large tongues compared to the bony confines of the oral cavity.

The Frequency of Lingual Tonsil Enlargement in Obese Children

OBJECTIVEnEnlargement of the lingual tonsils is being increasingly recognized as a not uncommon and treatable cause of obstructive sleep apnea, particularly in patients with Down syndrome who have undergone palatine tonsillectomy and adenoidectomy. We have recognized an increasing number of patients who are obese and have obstructive sleep apnea with enlarged lingual tonsils. The purpose of this study was to evaluate the frequency of enlarged lingual tonsils in obese children.nnnSUBJECTS AND METHODSnSeventy-one obese children (mean body mass index = 41.6 kg/m(2)) underwent sagittal fast spin-echo inversion recovery imaging. Lingual tonsils were identified and measured in the greatest anteroposterior diameter. Lingual tonsils > 10 mm were considered markedly enlarged. The subgroup with absent palatine tonsils (previous tonsillectomy) (n = 41) were compared with those with palatine tonsils present (n = 30).nnnRESULTSnForty-four (62%) of the obese children had measurable lingual tonsils, which is greater than the frequency previously reported in normal subjects (0%), subjects with obstructive sleep apnea (33%), or subjects with Down syndrome and obstructive sleep apnea (50%). Ten (14%) had lingual tonsils > 10 mm. Obese subjects with absent palatine tonsils (previous tonsillectomy) had a higher prevalence of measurable lingual tonsils than those with palatine tonsils (78% vs 22%, respectively; p < 0.001) and a higher prevalence of lingual tonsils > 10 mm (90% vs 10%, p < 0.001).nnnCONCLUSIONnObese children have a high frequency of enlargement of the lingual tonsils with a significantly higher prevalence in those with previous tonsillectomy. Enlarged lingual tonsils may play a role in the pathogenesis of obstructive sleep apnea in obese children.

CT findings for blebs and bullae in children with spontaneous pneumothorax and comparison with findings in normal age-matched controls

BackgroundSpontaneous pneumothorax (SPTX) is a relatively common condition. In patients with SPTX, CT has been advocated to identify blebs and bullae (BB) to help in management planning.PurposeThe study was designed to assess our experience with CT evaluation for underlying BB in children with SPTX as compared to normal controls.Materials and methodsForty-three children (mean age 16xa0years, range 13–19xa0years) with 50 SPTX events with both chest radiographs and CT scans were reviewed. CT findings were compared with those seen in 29 age- and gender-matched controls without SPTX. The parameters evaluated included size, number, location, and ipsi-/contralateral BB; apical lines; and surgical correlation.ResultsIn the study group, BB were identified in 14 imaged events (28%) (size 2.5–45xa0mm, one to six BB) with contralateral BB in 11 of the 14 (78.6%). All BB were confined to the apices. BB were sometimes difficult to differentiate from “apical lines”—a suspected normal variant seen in 28 imaged events (56%). Of blebs seen at surgery, 59% were identified on CT, and there were no false-positive CT findings. In the control group, no BB were identified but “apical lines” were seen in eight children (28%).ConclusionBB were seen by CT in 28% of imaged events in children with SPTX and were always confined to the apices. When present, BB were commonly bilateral (78.6%). BB should not be confused with “apical lines,” which were not only seen in 56% of imaged events in the SPTX group but also in 28% of the normal controls.

Prenatal MRI Findings of Fetuses with Congenital High Airway Obstruction Sequence

Objective To define the MRI findings of congenital high airway obstruction sequence (CHAOS) in a series of fetuses. Materials and Methods Prenatal fetal MR images were reviewed in seven fetuses with CHAOS at 21 to 27 weeks of gestation. The MRI findings were reviewed. The MRI parameters evaluated included the appearance of the lungs and diaphragm, presence or absence of hydrops, amount of amniotic fluid, airway appearance, predicted level of airway obstruction, and any additional findings or suspected genetic syndromes. Results All the fetuses viewed (7 of 7) demonstrated the following MRI findings: dilated airway below the level of obstruction, increased lung signal, markedly increased lung volumes with flattened or inverted hemidiaphragms, massive ascites, centrally positioned and compressed heart, as well as placentomegaly. Other frequent findings were anasarca (6 of 7) and polyhydramnios (3 of 7). MRI identified the level of obstruction as laryngeal in five cases and tracheal in two cases. In four of the patients, surgery or autopsy confirmed the MRI predicted level of obstruction. Associated abnormalities were found in 4 of 7 (genetic syndromes in 2). Postnatal radiography (n = 3) showed markedly hyperinflated lungs with inverted or flattened hemidiaphragms, strandy perihilar opacities, pneumothoraces and tracheotomy. Two fetuses were terminated and one fetus demised in utero. Four fetuses were delivered via ex utero intrapartum treatment procedure. Conclusion MRI shows a consistent pattern of abnormalities in fetuses with CHAOS, accurately identifies the level of airway obstruction, and helps differentiate from other lung abnormalities such as bilateral congenital pulmonary airway malformation by demonstrating an abnormally dilated airway distal to the obstruction.

Late gestation fetal magnetic resonance imaging–derived total lung volume predicts postnatal survival and need for extracorporeal membrane oxygenation support in isolated congenital diaphragmatic hernia

PURPOSEnMagnetic resonance imaging (MRI) has been used as an imaging modality to assess pulmonary hypoplasia in congenital diaphragmatic hernias (CDHs). The objective of this study was to determine if there is a correlation between late gestational fetal MRI-derived total lung volumes (TLVs) and CDH outcomes.nnnMETHODSnFrom 2006 to 2009, 44 patients met criteria of an isolated CDH with a late gestational MRI evaluation. The prenatal TLV (in milliliters) was obtained between 32 and 34 weeks gestation. The measured study outcomes included survival, need for extracorporeal membrane oxygenation (ECMO), and length of stay.nnnRESULTSnThere were 39 left and 5 right CDH patients. The average TLV was significantly lower for nonsurvivors (P = .01), and there was a significant association between lower TLV and the need for ECMO (P = .0001). When stratified by TLV, patients with a TLV of greater than 40 mL had a 90% survival vs 35% survival for a TLV of less than 20 mL. Furthermore, patients with a TLV greater than 40 mL had a lower rate of ECMO use (10%) than patients with a TLV of less than 20 mL (86%). Shorter length of stay was found to correlate with increasing TLV (P = .022).nnnCONCLUSIONnLate gestation fetal MRI-derived TLV significantly correlates with postnatal survival and need for ECMO. Fetal MRI may be useful for the evaluation of patients who present late in gestation with a CDH.

Prenatal diagnosis of cloacal malformations

IntroductionPrenatal diagnosis of anorectal malformations currently occurs in 0–15.9% of screened cases. In cloacas, these numbers are unknown. We speculate that some images from prenatal ultrasound studies may suggest the diagnosis of cloaca, but are not recognized because of a lack of suspicion for this diagnosis.MethodsA retrospective review of the medical records of 489 patients born with cloaca was performed; 95 of them had prenatal ultrasound reports that represent the material analyzed for this study. A literature review was performed, finding 31 publications, with 68 cloaca patients detected by prenatal images. The abnormal findings of our patients were compared with those described in the literature to determine the most common abnormal prenatal images found in patients with cloaca.ResultsThe 95 ultrasound reports found in our patients described 270 abnormalities, the most frequent were: abdominal/pelvic cystic/mass (39), hydronephrosis (36), oligohydramnios (23), distended bowel/bowel obstruction (19), ascites (15), 2 vessel cord (14), dilated bladder (14), dilated ureter (14), polyhydramnios (10), echogenic bowel (8), multicystic kidney (8), “ambiguous genitalia” (7), hydrops fetalis (7), hydrocolpos (4), absent kidney (3), abnormal spine (3), and anorectal atresia (3). In spite of these findings, the radiologists who interpreted the studies only suspected a cloaca in 6 cases (6%). The literature review showed 212 abnormalities in 68 demonstrated cloaca patients. The most frequent were: abdominal/pelvic cystic/mass (46), hydronephrosis (44), ascites (21), oligohydramnios (20), distended bowel (11), multicystic dysplastic kidney (7), ambiguous genitalia (6), non-visualization of the bladder (6), two-vessel cord (5), dilated bladder (5), intraabdominal calcification (4), polyhydramnios (4), enterolithiasis (4), hydrometrocolpos (3), and dilated ureter (3).ConclusionWe conclude that it is possible to suspect the diagnosis of cloaca, prenatally, more frequently than what currently occurs, looking at the same images but with an increased index of suspicion for cystic abdominal masses and a combination of gastrointestinal and urological abnormalities.

Fetal MRI of cloacal exstrophy

BackgroundPrenatal ultrasonographic (US) diagnosis of cloacal exstrophy (CE) is challenging.ObjectiveTo define the fetal MRI findings in CE.Materials and methodsWe performed a retrospective review of eight patients with CE. Imaging was performed between 22xa0weeks and 36xa0weeks of gestation with US in four and MRI in eight fetuses. Abdominal wall, gastrointestinal/genitourinary, and spine and limb abnormalities detected were compared with postnatal evaluation.ResultsUS failed to display CE in one of the four fetuses. Fetal MRI confirmed CE in all eight fetuses by demonstrating absence of a normal bladder and lack of meconium-filled rectum/colon, associated with protuberant pelvic contour and omphalocele. These findings correlated postnatally with CE, atretic hindgut and omphalocele. One fetus had imaging before rupture of the cloacal membrane, showing a protruding pelvic cyst. Absent bladder was noted in the remaining seven fetuses. Confirmed skin-covered spinal defects were noted in seven fetuses, low conus/tethered cord in one and clubfoot in three. Six fetuses had renal anomalies, two had hydrocolpos and one had ambiguous genitalia.ConclusionFetal MRI provides a confident diagnosis of CE when a normal bladder is not identified, there is a protuberant abdominopelvic contour and there is absence of meconium-filled rectum and colon. Genitourinary and spinal malformations are common associations.

MRI findings in multifetal pregnancies complicated by twin reversed arterial perfusion sequence (TRAP)

BackgroundTwin reversed arterial perfusion sequence (TRAP) is a rare complication in multifetal monochorionic pregnancies in which a normal “pump” twin provides circulation to an abnormal acardiac co-twin, resulting in high-output cardiac dysfunction in the pump twin.ObjectiveTo define fetal MRI findings of TRAP sequence.Materials and methodsFetal MR images were retrospectively reviewed in 35 pregnancies complicated by TRAP sequence. Abnormalities of the pump twin, acardiac twin, umbilical cord, placenta and amniotic fluid were reviewed.ResultsAcardiac twins were classified as: acephalus (51%), anceps (40%), amorphus (9%), acormus (0%). Common findings in acardiac twins include subcutaneous edema (77%), absent cardiac structures (86%), absent or abnormal thoracic cavity (100%), abnormal abdominal organs (100%), superior limbs absent (46%) or abnormal (51%), and inferior limbs present but abnormal (83%). There were pump twin findings of cardiac dysfunction in 43% and intracranial ischemic changes in 3%. Umbilical cord anomalies were present in 97%.ConclusionAcardiac twins present with a predictable pattern of malformation with poorly developed superior structures, more normally formed inferior structures and absent or rudimentary heart. Although usually absent, abnormal heart structures can be seen and do not exclude TRAP sequence. Pump twins are commonly normal with exception of findings of cardiac dysfunction and possible brain ischemia.

Easily overlooked sonographic findings in the evaluation of neonatal encephalopathy: lessons learned from magnetic resonance imaging.

Findings of neonatal encephalopathy (NE) and specifically those of hypoxic-ischemic injury are frequently evident on magnetic resonance imaging (MRI). Although MRI has become more widely used and has gained widespread acceptance as the study of choice for the evaluation of NE in recent years, its costs are high and access to MRI is sometimes limited for extremely sick neonates. Therefore, head sonography (US) continues to be the first-line imaging modality for the evaluation of the brain in neonates with NE; furthermore, in many of these infants, the diagnosis of NE may have first been made or suggested using head US. US is noninvasive, inexpensive, and portable, allowing examinations to be performed without moving the infant. However, many of the telltale signs of NE on US are subtle and may be easily overlooked, contributing to diagnostic delay or misdiagnosis. We aim to illustrate the spectrum of US findings in NE, with emphasis on those findings that may be easily overlooked on US. Recognition of these findings could potentially improve detection rates, reduce errors, and improve patient management.

Prenatal imaging of amniotic band sequence: utility and role of fetal MRI as an adjunct to prenatal US

BackgroundAmniotic band sequence and its US manifestations have been well-described. There is little information, however, regarding the accuracy and utility of fetal MRI.ObjectiveTo describe the MRI findings in amniotic band sequence and to compare the diagnostic accuracy of MRI and US.Materials and methodsPrenatal MRI and US studies were retrospectively reviewed in 14 consecutive pregnancies with confirmed amniotic band sequence. Both studies were evaluated for amniotic band visualization, body part affected, type of deformity, umbilical cord involvement and vascular abnormality.ResultsAmniotic bands were confidently identified with MRI in 8 fetuses (57%), suggested with MRI in 3 fetuses (21%) and confidently seen by US in 13 fetuses (93%). Neither modality detected surgically proven bands on one fetus. Both techniques were equally able to define the body part affected and the type of deformity. At least one limb abnormality was visualized in all cases and truncal involvement was present in two cases. Cord involvement was identified in seven cases, with one case detected only by MRI.ConclusionFetal MRI is able to visualize amniotic bands and their secondary manifestations and could be complementary to prenatal US when fetal surgery is contemplated.