The Clinical Value of Cranial CT Venography for Predicting Fusobacterium necrophorum as the Causative Agent in Children with Complicated Acute Mastoiditis.

BACKGROUND AND PURPOSE: Fusobacterium necrophorum (F necrophorum) is an anaerobic bacteria that causes invasive head and neck infections in children. Several studies have demonstrated an increasing prevalence of F necrophorum as the causative agent in acute mastoiditis in children, with associated high rates of intracranial complications such as epidural abscess and sinus venous thrombosis, to name a few. F necrophorum requires a treatment protocol that differs from the empiric treatment that is tailored to more common pathogens (eg, group A streptococci, Streptococcus pneumonia), and hence expediting the diagnosis is important. For evaluating complicated acute mastoiditis in children, cranial CT venography remains the imaging study of choice in most medical centers due to its availability in emergency situations. Based on our clinical experience, our hypothesis is that children with F necrophorum-associated complicated acute mastoiditis can be differentiated from those with other etiologies using CT venography. MATERIALS AND METHODS: CT venography studies of 76 children hospitalized and treated for complicated acute mastoiditis were retrospectively reviewed. Retrieved imaging data included intracranial complications (epidural abscess, sinus venous thrombosis), cranial bone-related complications, and extracranial complications (subperiosteal abscess, temporomandibular joint abscess, and soft-tissue inflammation). The cohort was divided into children with F necrophorum-related disease (study group) and those with non-F necrophorum-related disease (control group). RESULTS: Thirty-seven children (49%) comprised the study group, and 39 children in whom the causative agents were other bacteria comprised the control group. There were significantly higher rates of complications in the study group: sinus venous thrombosis (P < .001), perisigmoid epidural abscess (P = .036), and extramastoid osteomyelitis (P < .001). Thrombosis in venous sites beyond the sigmoid sinus and jugular foramen (a pattern consistent with an otogenic variant of Lemierre syndrome) and emphysematous osteomyelitis were found only among children in the F necrophorum-related study group (32% and 22% accordingly). CONCLUSIONS: In children with complicated acute mastoiditis, CT venography findings of emphysematous osteomyelitis and/or thrombosis in venous sites beyond the sigmoid sinus and jugular foramen (a pattern consistent with the otogenic variant of Lemierre syndrome) should lead the radiologist to suggest F necrophorum-related mastoiditis.

The prepontine block and its relevance for the development and treatment of hydrocephalus.

OBJECTIVE: Pulsatile CSF flow patterns include flow through the ventricles to the subarachnoid space and cisterns and from the infra- to the supratentorial subarachnoid space. In this study, we demonstrate how an obstruction at the level of the prepontine space may lead to obstructive hydrocephalus with specific radiological characteristics, as well as the implications for treatment options. METHODS: We retrospectively collected data of patients who underwent surgery between February 2010 and December 2022 for hydrocephalus secondary to a suspected prepontine block. One additional patient diagnosed with prepontine block who did not undergo surgery was also included. We excluded patients with a background of previous unrelated neurosurgical procedures or CNS infections. RESULTS: Six children and two adults were included. Three presented with hydrocephalus on imaging, without any other underlying pathology. Five had a suprasellar arachnoid cyst, with its lower border abating the pons and occluding the spinal subarachnoid space (SAS). All cases had an open aqueduct on T2 sagittal sequences, as well as an infracerebellar or retrocerebellar CSF collection. In most cases, a horizontal web was identified in the prepontine region. Seven cases were treated with an endoscopic fenestration. One patient subsequently underwent a shunt surgery. All the operated children reached normal developmental milestones after surgery. CONCLUSIONS: This paper describes a rather small series of cases where clear obstruction was observed at the level of the prepontine subarachnoid space. We believe this anatomical subtlety adds to a better understanding of CSF pathways and the role of ETV in treating hydrocephalus, focusing on a small subgroup of patients without a clear obstruction.

Non-ionizing measurement and quantification of bell-shaped chests in spinal muscular atrophy: a pilot study.

Background: Spinal Muscular Atrophy (SMA) is manifested by deformation of the chest wall, including a bell-shaped chest. We determined the ability of a novel non-ionizing, non-volitional method to measure and quantify bell-shaped chests in SMA. Methods: A 3D depth camera and a chest x-ray (CXR) were used to capture chest images in 14 SMA patients and 28 controls. Both methods measure the distance between two points, but measurements performed by 3D analysis allow for the consideration of the curve of a surface (geodesic measurements), whereas the CXR allows solely for the determination of the shortest path between two points, with no regard for the surface (Euclidean measurements). The ratio of the upper to lower chest distances was quantified to distinguish chest shape in imaging by both the 3D depth camera and the CXR, and the ratios were compared between healthy and SMA patients. Results: The mean 3D Euclidean ratio of distances measured by 3D imaging was 1.00 in the control group and 0.92 in the SMA group (p = 0.01), the latter indicative of a bell-shaped chest. This result repeated itself in the ratio of geodesic measurements (0.99 vs. 0.89, respectively, p = 0.03). Conclusion: The herein-described novel, noninvasive 3D method for measuring the upper and lower chest distances was shown to distinguish the bell-shaped chest configuration in patients with SMA from the chests of controls. This method bears several advantages over CXR and may be readily applicable in clinical settings that manage children with SMA.

Skull Base Osteomyelitis in Children: Clinical Characteristics and Potential Implications.

OBJECTIVES: We describe 10 new cases of otogenic (n = 8) and nonotogenic (n = 2) skull base osteomyelitis (SBO) in previously healthy children and review the literature on SBO in the pediatric population. METHODS: We retrospectively analyzed the medical records of 10 children (age range 0.9-12.8 years) discharged with a diagnosis of SBO between 2015 and 2020 in 2 children's hospitals in central Israel. RESULTS: Five patients presented with fever and 5 with otological signs and symptoms. All 10 children underwent a comprehensive clinical evaluation, imaging studies (computerized tomography or magnetic resonance imaging) and laboratory investigations. The physical examination revealed neurologic findings, including nuchal rigidity, papilledema, and apathy, in 4 patients. All 8 otogenic patients underwent surgical intervention and the 2 nonotogenic patients, who were diagnosed as having deep neck and throat infections, responded well to treatment consisting of antibiotics without surgery. CONCLUSIONS: Early diagnosis of pediatric SBO can be challenging because the symptoms are often nonspecific. The final diagnosis relies mainly on imaging, preferably magnetic resonance imaging. Surgical intervention is usually mandatory in the otogenic patients, whereas the nonotogenic patients respond well to medical management alone.

Upper gastrointestinal series in healthy neonates with bilious vomiting-is it still obvious? A retrospective observational study.

AIM: Demand for upper gastrointestinal contrast series (UGI) to investigate bilious vomiting (BV) has increased in recent years, mostly due to greater awareness of the need to rule out malrotation and midgut volvulus (MGV). We aimed to examine predictive value of clinical parameters in the management of healthy neonates presenting with BV and re-assess the role of UGI in their management. METHODS: A retrospective cohort study including medical, imaging and surgical data of neonates who underwent UGI due to BV. RESULTS: A total of 157 term neonates, eight neonates (5.1%) had confirmed surgical diagnosis of malrotation, five of them had malrotation with MGV, including two neonates who underwent extensive intestinal resection due to necrosis. Neonates with a combination of abnormal plain radiograph and abdominal distention had 10 times higher odds of malrotation diagnosis, adjusting for age at first BV (p = 0.017). Neonates with a combination of abnormal plain radiograph, abdominal distention and abdominal tenderness had 25 times higher odds of MGV (p = 0.002). CONCLUSION: This study reaffirms the role of UGI as the current main diagnostic tool for malrotation and MGV. Physical examination and plain radiograph findings can help but cannot substitute UGI study.

Pediatric low-dose head CT: Image quality improvement using iterative model reconstruction.

PURPOSE: To evaluate the differences in pediatric non-contrast low-dose head computed tomography (CT) between filtered-back projection and iterative model reconstruction using objective and subjective image quality evaluation. METHODS: A retrospective study evaluated children undergoing low-dose non-contrast head CT. All CT scans were reconstructed using both filtered-back projection and iterative model reconstruction. Objective image quality analysis was performed using contrast and signal-to-noise ratios for the supra- and infratentorial brain regions of identical regions of interest on the two reconstruction methods. Two experienced pediatric neuroradiologists evaluated subjective image quality, visibility of structures, and artifacts. RESULTS: We evaluated 233 low-dose brain CT scans of 148 pediatric patients. There was a ∼2-fold improvement in the contrast-to-noise ratio between gray and white matter in the infra- and supratentorial regions (p < 0.001) using iterative model reconstruction compared to filtered-back projection. The white and gray matter signal-to-noise ratio improved more than 2-fold using iterative model reconstruction (p < 0.001). Furthermore, radiologists graded anatomical details, gray-white matter differentiation, beam hardening artifacts, and image quality using iterative model reconstructions as superior to filtered-back projection reconstructions. CONCLUSION: Iterative model reconstructions had better contrast-to-noise and signal-to-noise ratios with fewer artifacts in pediatric CT brain scans using low-dose radiation protocols. This image quality improvement was demonstrated in the supra- and infratentorial regions. This method thus comprises an important tool for reducing children's exposure while maintaining diagnostic capability.

Prevalence and management of methotrexate-induced neurotoxicity in pediatric patients with osteosarcoma: a single-center experience.

AIMS: To determine the incidence, clinical presentation, and outcome of methotrexate (MTX) associated neurotoxicity in pediatric patients treated for osteosarcoma, with the aim of identifying possible risk factors and suggesting recommended treatment for these sequelae. MATERIALS AND METHODS: All medical files of patients treated for osteosarcoma in a single pediatric haemato-oncology center between November 2011 and August 2021 were retrospectively reviewed. All patients were treated according to the EURAMOS AOST0331 protocol, using cisplatin, doxorubicin, and high-dose MTX at a dose of 12 g/m2 over 4 h. RESULTS: Seventy-eight patients with osteosarcoma were identified (age range 5 to 23 years, 42 males). Seven patients (9%) sustained neurotoxicity following treatment with high-dose MTX. Manifestations of neurotoxicity included among others, generalized seizures, confusion, encephalopathy, dysarthria, and choreiform movements. All but one episode occurred following two sequential cycles of high-dose MTX. All 7 had subacute toxicity, 5-10 days following MTX administration, and 1 had both acute and subacute toxicity. Brain MRI was performed for all patients and demonstrated typical MRI changes attributed to MTX neurotoxicity in 4 of them. Two patients received aminophylline; one patient received dextromethorphan. Patients with normal MRI imaging resumed MTX therapy without any sequels. No risk factors were found for high-dose MTX-related toxicity occurrence. CONCLUSIONS: The time of risk of neurotoxicity due to high-dose MTX treatment for osteosarcoma is days 5-10 following two sequential treatment cycles. These findings together with treatment options for these adverse effects should be detailed in the therapeutic protocol of MTX use among pediatric patients with osteosarcoma.

Utility of three-dimensional modeling of the fetal airway for ex utero intrapartum treatment.

Recent technological developments in three-dimensional (3D) printing have created new opportunities for applications in clinical medicine. 3D printing has been adopted for teaching and planning complicated surgeries, including maxillofacial, orthopedic reconstructions, and airway manipulation for one-lung ventilation or airway stenting. We present here the first use of such technology to print a model from in utero imaging for intrapartum treatment planning. A 32-week fetus presented with congenital high airway obstruction syndrome (CHAOS) due to a large cervical lymphatic malformation. An ex utero intrapartum treatment (EXIT) procedure was planned to allow delivery of a viable infant. We printed a 3D model of the fetal airway by printing separate elements: mandible, tongue, mass, larynx, and trachea from the fetal MRI. The elements were stuck together maintaining correct anatomical relationships. Airway planning was then performed in consultation with a pediatric ear nose and throat (ENT) surgeon. 3D modeling in utero presents many challenges: the resolution of the 3D model generated from a fetal MRI is less crisp than from CT images, fetal position may be variable and not in a defined anatomical plane, movement artifact occurs. Nevertheless, pre-procedure simulations with the aid of 3D modeling promoted team cooperation and well-prepared management of the fetus during EXIT.

Sarcopenia is a Predictor for Adverse Clinical Outcome in Pediatric Inflammatory Bowel Disease.

OBJECTIVES: Inflammatory bowel disease (IBD) has a high impact on nutritional status. Sarcopenia is related to higher risk of surgery and rescue therapy in adults with IBD; however, comparable data in pediatric populations are scarce. We evaluated muscle mass as a predictor of disease outcome in pediatric IBD. METHODS: All pediatric IBD patients who underwent magnetic resonance enterography (MRE) during 2008 to 2019 were included. Muscle mass was assessed by measuring the area of the psoas muscle at the upper level of L3 on MRE. The psoas area divided by the body surface area (BSA) yielded the psoas index. Clinical and radiological data, including disease location, activity, course, and medications were documented. The control group included non-IBD children who underwent an MR imaging study. RESULTS: We enrolled 101 IBD patients, 69 (68.3%) with Crohn disease (CD) and 32 (31.7%) with ulcerative colitis (UC) (mean age 15.03 ±â€Š3.27 years). The psoas index was significantly lower in the IBD patients compared with the 87 controls (326 vs 528, respectively, P < 0.001). Patients with a psoas index in the lowest quartile had significantly higher risk for biologic therapy (multivariate analysis, hazard ratio [HR] = 12.1, P = 0.046) and disease exacerbation (HR = 9, P = 0.047) independently of body mass index, compared with patients with a psoas index in the uppermost quartile. CONCLUSIONS: Sarcopenia correlates with the radiological severity of pediatric IBD and serves as a predictor for adverse clinical disease outcome. Muscle mass measurement in MRE studies may serve as a possible marker for disease outcome in this population.

Monogenic Causes of Apparently Idiopathic Perinatal Intracranial Hemorrhage.

OBJECTIVE: Perinatal intracranial hemorrhage (pICH) is a rare event that occurs during the fetal/neonatal period with potentially devastating neurological outcome. However, the etiology of pICH is frequently hard to depict. We investigated the role of rare genetic variations in unexplained cases of pICH. METHODS: We performed whole-exome sequencing (WES) in fetuses and term neonates with otherwise unexplained pICH and their parents. Variant causality was determined according to the American College of Medical Genetics and Genomics (ACMG) criteria, consistency between suggested genes and phenotypes, and mode of inheritance. RESULTS: Twenty-six probands (25 families) were included in the study (9 with a prenatal diagnosis and 17 with a postnatal diagnosis). Intraventricular hemorrhage (IVH) was the most common type of hemorrhage (n = 16, 62%), followed by subpial (n = 4, 15%), subdural (n = 4, 15%), and parenchymal (n = 2, 8%) hemorrhage. Causative/likely causative variants were found in 4 subjects from 3 of the 25 families (12%) involving genes related to the brain microenvironment (COL4A1, COL4A2, and TREX-1). Additionally, potentially causative variants were detected in genes related to coagulation (GP1BA, F11, Von Willebrand factor [VWF], FGA, and F7; n = 4, 16%). A potential candidate gene for phenotypic expansion related to microtubular function (DNAH5) was identified in 1 case (4%). Fifty-five percent of the variants were inherited from an asymptomatic parent. Overall, these findings showed a monogenic cause for pICH in 12% to 32% of the families. INTERPRETATION: Our findings reveal a clinically significant diagnostic yield of WES in apparently idiopathic pICH and support the use of WES in the evaluation of these cases. ANN NEUROL 2021;89:813-822.

Fetal Ventriculomegaly and Hydrocephalus - What Shouldn't be Missed on Imaging?

Fetal ventriculomegaly is one of the most frequently diagnosed abnormalities detected prenatally. The finding of additional subtle abnormalities can facilitate accurate prognoses, which may range from normal outcomes to significant neurodevelopmental sequelae. Pathogenesis and imaging patterns of ventriculomegaly and hydrocephalus in the fetus based on the pattern-recognition approach using fetal MRI are reviewed in this paper. This radiological approach may shed light on clinical course prediction and therapeutic efficacy of hydrocephalus in the fetus.

Diverse presentation and tailored treatment of infantile myofibromatosis: A single-center experience.

BACKGROUND: Infantile myofibromatosis (IM) is a rare benign fibrous tumor with diverse clinical presentations and treatments, such as watchful waiting, surgical excision, and low-dose chemotherapy. PROCEDURE: Clinical presentation and tailored treatment of five infants with solitary and generalized IM are described, together with a review of the literature. RESULTS: Three patients underwent total-body magnetic resonance imaging (MRI) at diagnosis and during follow up, which revealed disease extension that aided in designing treatment. Visceral involvement included central nervous system, cardiac, gastrointestinal, muscle, bone, and subcutaneous tissue lesions. The patient with the solitary form of IM was followed up without treatment and had spontaneous improvement. Patients with the multicentric form received intravenous low-dose methotrexate and vinblastine chemotherapy. One patient who received oral methotrexate due to cardiac involvement and unfeasible central line access had excellent results. Recurrence was successfully treated by the same methotrexate and vinblastine regimen as that administered at diagnosis. CONCLUSIONS: We suggest screening all patients with one or more IM lesions by means of total body MRI due to its inherent superior soft tissue resolution. Total-body MRI may also be used for routine follow up. Oral methotrexate can be administered successfully in patients that lack central line access, and recurrent lesions can be treated with the same chemotherapeutic combination as that given at diagnosis. Long-term follow up is needed, since recurrence could appear years after initial presentation of the disease.

Questioning the Value of Brain Magnetic Resonance Imaging in the Evaluation of Children with Isolated Growth Hormone Deficiency.

BACKGROUND: Isolated growth hormone deficiency (IGHD) is a relatively common disorder. Current diagnostic protocol requires a brain magnetic resonance imaging (MRI) study of the hypothalamus and the hypophysis to determine the cause after establishment of the diagnosis. This study aimed to examine the yield of brain MRI in the evaluation of children with IGHD and to define clinical and laboratory parameters that justify its performance. METHODS: A retrospective chart review of all children (<18 years) diagnosed with IGHD was conducted at 3 pediatric endocrinology units between 2008 and 2018. RESULTS: The study included 192 children (107 boys) with confirmed IGHD. The mean age ± standard deviation (SD) at diagnosis was 8.2 ± 3.7 years (median 8.5 years, range 0.8-15.9). The mean height SD score (SDS) at diagnosis was -2.25 ± 0.73. The mean height deficit SDS (defined as the difference between height SDS at diagnosis and mid-parental height SDS) was -1.7 ± 0.9. Fifteen children (7.8%) had pathological MRI findings. No space-occupying lesion was detected. Children with pathological MRIs had greater height deficit SDS and lower peak growth hormone levels on provocative tests compared to children with normal MRIs: -2.3 ± 1.2 vs. -1.6 ± 0.8 (p = 0.02) and 4.4 ± 1.9 vs. 5.7 ± 1.3 (p = 0.01), respectively. CONCLUSION: Our preliminary data indicate that most brain MRIs performed for routine evaluation of children with IGHD are not essential for determining cause. Further studies with larger cohorts are needed in order to validate this proposed revision of current protocols.

The role of ICP monitoring in paediatric IIH.

INTRODUCTION: Diagnosis of idiopathic intracranial hypertension (IIH) in children is an extrapolation of the guidelines suggested for adult population. Lumbar puncture (LP) plays a crucial role in the diagnosis. The diagnosis of IIH at times is solely dependent on the interpretation of the opening pressure (OP). Unfortunately, LP-OP can vary due circumstantial parameters and therefore may be an unreliable form of intracranial pressure (ICP) measurement. Confirming the diagnosis based (as suggested by guidelines) on LP-OP in a doubtful clinical situation would be inappropriate. The aim of our study was to analyse the reliability of LP-OP and importance of ICP monitoring in situations where diagnosis of IIH was questionable. METHODS: Retrospective review of all children with diagnosis of IIH over a 10-year period was conducted. Children who underwent ICP monitoring (ICPM) were selected. We considered 2 LP-OP values-last LP (lLP) and the mean LP (mLP) for analysis. ICPM and LP-OP were compared. Follow-up till last clinic visit was also considered for long-term outcome. RESULTS: Eleven children (male 3; female 8) were included in the study. Mean delay between LP and ICPM was 112.8 days (17-257 days). There was lack of correlation between LP-OP and ICP in 9 children. ICP monitoring refuted the diagnosis of IIH in 80% of children and prevented exposure to unnecessary medical and surgical intervention. There was 1complication with ICPM. In 90% of children, there was no progression of symptoms following a decision based on ICP monitoring on long-term follow-up (mean, 36.5 months). CONCLUSION: When the diagnosis of IIH is in doubt, LP may be unreliable and formal ICP monitoring is advised.

Incidental Findings on Brain Magnetic Resonance Imaging (MRI) in Pediatric Endocrine Patients.

OBJECTIVE: To explore incidental findings on brain magnetic resonance imaging (MRI) studies of pediatric patients referred due to endocrine disorders. METHODS: A retrospective, observational study conducted in a tertiary referral center. The neuroimaging database of 17,445 brain MRI studies of 11,011 pediatric patients were searched for cases with endocrine referrals and without medical history of malignancy, genetic syndromes, and/or neurologic comorbidities. This database was linked to the pediatric neurosurgical database. Clinical data were retrieved from medical files. RESULTS: In total, 524 patients (50.2% males, mean age 8.5±3.5 years) were referred to brain MRI due to growth disturbances (n = 313), pubertal disorders (n = 183), prolactin hypersecretion (n = 18), central diabetes insipidus (n = 8), and obesity (n = 1). Incidental findings were found in 128 (24.4%) cases. Chiari type 1 malformation was more prevalent in patients with growth disturbances (P<.001). Small pituitary cysts were observed in 20 (3.8%) patients, and pineal cysts in 25 (4.8%) patients, mostly girls (68%, P<.001). White matter lesions were diagnosed in 30 (5.7%) patients, none with clinical evidence of neurologic disease. Brain asymmetry without clinical significance and developmental venous anomalies were observed in 14 (2.7%) and 8 (1.5%) patients, respectively. Twelve patients were diagnosed with intracranial tumors, and 5 required surgical intervention for a histopathologic diagnosis of juvenile pilocytic astrocytoma (n = 3), choroid plexus papilloma (n = 1), or inconclusive (n = 1). The rest were managed conservatively. CONCLUSION: Incidental findings on brain MRIs of pediatric patients referred by endocrinologists are common and raise dilemmas. The spectrum ranges from structural disruptions to tumors. Decision-making is individualized and patient-centered.

A Case of Methotrexate Neurotoxicity Presented as Status Epilepticus, Encephalopathy, and High Fever.

High-dose methotrexate is used to treat a range of adult and childhood cancers including osteosarcoma. Significant neurotoxicity is reported in 1% to 4.5% of patients treated with high-dose methotrexate and can present in a wide variety of symptoms. We present a case of a 14-year-old boy with a recent diagnosis of osteosarcoma who presented to the emergency department with status epilepticus, altered mental status, and very high fever secondary to methotrexate neurotoxicity. We review current literature and discuss some controversies related to this state. We also describe high fever as one of the possible symptoms associated with this condition and suggest using specific magnetic resonance imaging sequence to uncover abnormal findings related to this state. Since high-dose methotrexate is not a rare treatment in this era, we believe that in addition to oncologists, emergency department and intensive care providers should be aware of the potential role of methotrexate in causing significant neurotoxicity and include it in the differential diagnosis when treating a patient presenting with new neurological symptoms in the setting of recent high-dose methotrexate treatment.

Mature teratoma splitting the brainstem in a newborn: case report.

Mature teratomas (MTs) of the posterior fossa are extremely rare. The authors present a case of a prenatal diagnosis of an MT splitting the brainstem. Representative images as well as the clinical and surgical course are presented. Literature regarding "split brainstem" and MT of the posterior fossa is discussed.

The Added Value of Magnetic Resonance Imaging Cisternography and Ventriculography as a Diagnostic Aid in Pediatric Hydrocephalus.

BACKGROUND: Magnetic resonance imaging (MRI) is the "gold standard" method for the evaluation of hydrocephalus. However, diagnosing an obstruction in the ventricular or subarachnoid spaces may pose a challenge for standard diagnostic sequences. In this study, we describe our experience with MRI cisternography (MRIC) or ventriculography (MRIV) for diagnosing or excluding intra- and extraventricular obstructions. Such a differentiation may have a significant impact on choosing the optimal surgical solution. METHODS: We retrospectively collected data on patients undergoing MRIC/MRIV for diagnosing or excluding obstructions in patients with ventriculomegaly. All patients had MRI suggesting an obstruction, but without a clear cause. RESULTS: Five children aged 1-17 years were included (3 females). Four underwent an MRIV, and 1 underwent an MRIC. Three children presented with headaches and had a suspected prior endoscopic third ventriculostomy (ETV) failure, and 2 presented with macrocephalus and increasing head circumferences. MRIV showed a patent ETV stoma in 2 cases, one of which had a T2 SPACE MRI showing no flow void through the stoma, and a closed stoma in 1 case with a flow void above and below the stoma on T2 SPACE MRI. MRIV and MRIC differentiated between two cases with panventriculomegaly, one of which had an obstruction at the level of the Liliequist membrane, and another with no identifiable obstruction. CONCLUSIONS: MRIC and MRIV have a complementary role to MRI in assessing selected patients with hydrocephalus suspected of being secondary to an obstruction, but with no clear obstruction location.