A case report of spinal toxocariasis with extensive tumor-like involvement.

BACKGROUND: Toxocariasis is a common parasitic infection worldwide. Although it can present as several clinical syndromes, neurological manifestation is rare. Only a few reports are available on spinal cord involvement of toxocariasis. We report a case that presented with gait disturbance due to progressive lower limb spasticity. The patient had had visceral toxocariasis infection 8 years before. A spine magnetic resonance image (MRI) showed syringomyelia along the entire thoracic cord with small nodular enhancing lesions in the mid-portion of the syrinx, which led to the suspicion of ependymoma. Surgical mass removal was performed. However, histopathological examination of the mass did not show any malignant cells; instead, there were numerous axonal retraction balls with an eosinophilic granular body-like appearance. The serum antibody titer against toxocariasis was borderline high. Taken together, these observations led to a diagnosis of Toxocara infection, and the patient was treated with albendazole. CONCLUSION: To the best of our knowledge, this is the first case report of tumor-like spinal toxocariasis involving extensive lesions. A solid enhancing mass with accompanied syrinx and hemorrhage might be a Toxocara infection. It can easily be diagnosed with serologic tests and simply be treated with oral albendazole if suspected.

Cardiac autonomic dysfunction is associated with hypothalamic damage in patients with childhood-onset craniopharyngioma.

BACKGROUND: Autonomic nervous system dysfunction is implicated in the development of hypothalamic obesity. We investigated the relationship between hypothalamic involvement (HI), central obesity, and cardiac autonomic dysfunction by assessing heart rate variability (HRV) indices in patients with childhood-onset craniopharyngioma. METHODS: A cross-sectional study of 48 patients (28 males, 10-30 years old) with hypothalamic damage after childhood-onset craniopharyngioma was performed. Postoperative HI was graded as mild (n = 19) or extensive (n = 29) on magnetic resonance imaging. Anthropometry, body composition and HRV indices including the standard deviation of all normal R-R intervals (SDNN) and total power (TP) as overall variability markers, root-mean square differences of successive R-R intervals (RMSSD) and high frequency (HF) as parasympathetic modulation markers, and low frequency (LF) as a sympathetic/sympathovagal modulation marker were measured. RESULTS: Patients with extensive HI had increased means of body mass index, waist circumference, and fat mass than those with mild HI (P < 0.05, for all). Centrally obese patients had a lower mean HF, a parasympathetic modulation marker, than centrally non-obese patients (P < 0.05). The extensive HI group had lower means of overall variability (SDNN and TP), parasympathetic modulation (HF), and sympathetic/sympathovagal modulation (LF) than the mild HI group (P < 0.05, for all). The interaction effect of HI and central obesity on HRV indices was not significant. In models adjusted for age, sex, and family history of cardiometabolic disease, the means of the overall variability indices (P < 0.05 for both SDNN and TP) and a sympathetic/sympathovagal modulation index (P < 0.05 for LF) were lower with extensive HI, without differences according to central obesity. CONCLUSIONS: The reduced HRV indices with extensive HI suggests that hypothalamic damage may contribute to cardiac autonomic dysfunction, underscoring the importance of minimizing hypothalamic damage in patients with childhood-onset craniopharyngioma.

Autonomic Dysfunction is Associated with Increased Cardiometabolic Risk in Patients with Childhood-Onset Craniopharyngioma.

Patients with craniopharyngioma are susceptible to autonomic dysfunction as a result of hypothalamic damage. We evaluated indices of heart rate variability (HRV) in patients with childhood-onset craniopharyngioma to investigate autonomic function and its relationship with components of the metabolic syndrome (MetS). This cross-sectional, case-only study included 53 patients (10-30 years of age). We measured the standard deviation of all normal R-R intervals (SDNN) and total power indicating overall HRV, the root-mean square of the difference of successive R-R intervals (RMSSD) and high frequency indicating parasympathetic modulation, and low frequency. These indices were compared according to the presence of the MetS. During the mean 10.8 years of follow-up, 25% of patients were diagnosed with the MetS. Patients with the MetS showed significantly lower levels of SDNN (29.0 vs. 40.6 ms), total power (416.1 vs. 1129.6 ms2), RMSSD (20.1 vs. 34.5 ms), high frequency (94.7 vs. 338.5 ms2), and low frequency (94.5 vs. 289.4 ms2) than those without (p <0.05, for all). Individual components of the MetS including insulin resistance, serum triglycerides levels, and systolic blood pressure were inversely associated with SDNN, total power, RMSSD and high frequency. Higher overall variability and parasympathetic modulation were related to decreased odds ratios for having the MetS (OR 0.91, p=0.029 for SDNN; OR 0.91, p=0.032 for total power). In conclusion, autonomic dysfunction, as evidenced by reduced HRV indices, is associated with increased cardiometabolic risk in patients with childhood-onset craniopharyngioma.

Computerized texture analysis of pulmonary nodules in pediatric patients with osteosarcoma: Differentiation of pulmonary metastases from non-metastatic nodules.

OBJECTIVE: To retrospectively evaluate the value of computerized 3D texture analysis for differentiating pulmonary metastases from non-metastatic lesions in pediatric patients with osteosarcoma. MATERIALS AND METHODS: This retrospective study was approved by the institutional review board. The study comprised 42 pathologically confirmed pulmonary nodules in 16 children with osteosarcoma who had undergone preoperative computed tomography between January 2009 and December 2014. Texture analysis was performed using an in-house program. Multivariate logistic regression analysis was performed to identify factors for differentiating metastatic nodules from non-metastases. A subgroup analysis was performed to identify differentiating parameters in small non-calcified pulmonary nodules. The receiver operator characteristic curve was created to evaluate the discriminating performance of the established model. RESULTS: There were 24 metastatic and 18 non-metastatic lesions. Multivariate analysis revealed that higher mean attenuation (adjusted odds ratio [OR], 1.014, P = 0.003) and larger effective diameter (OR, 1.745, P = 0.012) were significant differentiators. The analysis with small non-calcified pulmonary nodules (7 metastases and 18 non-metastases) revealed significant inter-group differences in various parameters. Logistic regression analysis revealed that higher mean attenuation (OR, 1.007, P = 0.008) was a significant predictor of non-calcified pulmonary metastases. The established logistic regression model of subgroups showed excellent discriminating performance in the ROC analysis (area under the curve, 0.865). CONCLUSION: Pulmonary metastases from osteosarcoma could be differentiated from non-metastases by using computerized texture analysis. Higher mean attenuation and larger diameter were significant predictors for pulmonary metastases, while higher mean attenuation was a significant predictor for small non-calcified pulmonary metastases.

Effect of low tube voltage and low iodine concentration abdominal CT on image quality and radiation dose in children: preliminary study.

PURPOSE: To evaluate the image quality of a double-low protocol (low tube voltage and low iodine concentration) for abdominal CT in children. MATERIALS AND METHODS: The double-low protocol was compared to the conventional protocol in pediatric patients weighing less than 40 kg from May 2016 to December 2016. Double-low protocol (Group A, n = 18): tube voltage, 70 kVp; and iodine concentration,: 250 mgI/mL versus Conventional protocol (Group B, n = 13): tube voltage, 80-100 kVp; and iodine concentration, 350 mgI/mL. Mean attenuation, noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were compared between the two groups. Image contrast, noise, beam-hardening artifacts, and overall image quality were subjectively scored. Reader performance for correctly differentiating two groups by visual assessment was evaluated. Radiation dose and total iodine load were recorded. RESULTS: The mean attenuations of the portal vein and liver and the mean image noise in Group A were higher than in Group B (p = 0.04, 0.03, 0.004, respectively). The mean SNR and CNR of the main portal vein and liver were lower in Group A without any statistically significant difference. There were no statistically significant differences between the two groups in qualitative analysis (image contrast, image noise, and overall image quality) with substantial agreement between the reviewers (weighted kappa values; 0.59-0.76). Significantly diminished radiation dose and iodine load were observed in Group A compared with Group B (25.0%, 36.8% reduction; p = 0.007, 0.006, respectively). CONCLUSION: The double-low protocol was feasible for pediatric abdominal CT and reduced both radiation dose and iodine load, while maintaining image quality.

Radiologic evaluation of pulmonary injury following carmustine- and cyclophosphamide-based preparative regimen for autologous peripheral blood stem cell transplantation in children.

BACKGROUND: Toxicity of carmustine and cyclophosphamide can cause pulmonary injury after hematopoietic stem cell transplantation. OBJECTIVE: To evaluate the radiologic findings of pulmonary injuries following carmustine- and cyclophosphamide-based preparative regimens in children. MATERIALS AND METHODS: From 2010 to 2014, 35 children received carmustine- and cyclophosphamide-based preparative regimens. Fourteen of 35 children presented with symptoms and radiologic abnormalities. Eight of 14 children had no evidence of infection, cardiogenic edema, or other explainable causes. We retrospectively analyzed their chest radiographs and CT scans for ground-glass opacity, consolidation, septal thickening and pleural effusion. RESULTS: Major chest radiographic findings were bilateral diffuse ground-glass opacity (n=8) and septal thickening (n=7). CT findings were multifocal patchy (n=4) or inhomogeneously diffuse (n=4) ground-glass opacity, multifocal consolidations (n=7) and septal thickening (n=7). All of these lesions at CT were bilateral, but showed lower lobe predominance in 88, 100, and 63%, respectively. There was no central/peripheral or anterior/posterior predilection. Six children had small pleural effusions, which were bilateral in five children. CONCLUSION: Bilateral ground-glass opacity with or without consolidation, septal thickening and pleural effusion were common radiologic findings in pulmonary injury following carmustine- and cyclophosphamide-based preparative regimens.

Unenhanced 320-row multidetector computed tomography of the brain in children: comparison of image quality and radiation dose among wide-volume, one-shot volume, and helical scan modes.

BACKGROUND: The 320-row multidetector computed tomography (CT) scanner has multiple scan modes, including volumetric modes. OBJECTIVE: To compare the image quality and radiation dose of 320-row CT in three acquisition modes - helical, one-shot volume, and wide-volume scan - at pediatric brain imaging. MATERIALS AND METHODS: Fifty-seven children underwent unenhanced brain CT using one of three scan modes (helical scan, n=21; one-shot volume scan, n=17; wide-volume scan, n=19). For qualitative analysis, two reviewers evaluated overall image quality and image noise using a 5-point grading system. For quantitative analysis, signal-to-noise ratio, image noise and posterior fossa artifact index were calculated. To measure the radiation dose, adjusted CT dose index per unit volume (CTDIadj) and dose length product (DLP) were compared. RESULTS: Qualitatively, the wide-volume scan showed significantly less image noise than the helical scan (P=0.009), and less streak artifact than the one-shot volume scan (P=0.001). The helical mode showed significantly lower signal-to-noise ratio, with a higher image noise level compared with the one-shot volume and wide-volume modes (all P<0.05). The CTDIadj and DLP were significantly lower in the one-shot volume and wide-volume modes compared with those in the helical scan mode (all P<0.05). CONCLUSION: For pediatric unenhanced brain CT, both the wide-volume and one-shot volume scans reduced radiation dose compared to the helical scan mode, while the wide-volume scan mode showed fewer streak artifacts in the skull vertex and posterior fossa than the one-shot volume scan.

Gallbladder wall oedema and ascites are independent predictors of progression to hepatic veno-occlusive disease for children with hematopoietic stem cell transplantation.

OBJECTIVES: To evaluate the predictive value of ultrasonography in children with clinically suspicious hepatic veno-occlusive disease (VOD) after hematopoietic stem cell transplantation (HSCT). METHODS: Among 216 children who underwent HSCT, 70 also underwent colour Doppler ultrasonography. Of these, 59 had only one sign/symptom, which did not fulfil the diagnostic criteria (clinical suspicion of VOD) at that time. VOD was confirmed in 20 patients (VOD group), while 39 had other conditions (non-VOD group). The following findings were reviewed and compared between groups: left portal vein (peak velocity, direction), left hepatic artery (peak-systolic/end-diastolic velocities, resistive index), middle hepatic vein (peak velocity, phasicity), hepatomegaly, splenomegaly, gallbladder wall thickness, and ascites. RESULTS: The VOD group showed significantly higher reversed flow in portal vein (P = 0.011), peak systolic velocity of left hepatic artery (P = 0.028), monophasicity of middle hepatic vein (P = 0.015), hepatomegaly (P = 0.001), gallbladder wall thickness (P < 0.001), and ascites (P < 0.001). Multivariate regression revealed that gallbladder wall thickness and ascites (odds ratio = 35.370, 56.393) were associated with VOD. CONCLUSIONS: The presence of reversed flow in portal vein, increased peak systolic velocity of hepatic artery, monophasicity of hepatic vein, hepatomegaly, gallbladder wall thickness, and ascites were significantly associated with progression to VOD in children with clinically suspicious VOD after HSCT. KEY POINTS: • Ultrasonography with Doppler can help predict progression to VOD. • Gallbladder wall oedema and ascites are the independent predictors of progression to VOD.

Benign extracerebral fluid collection complicated by subdural hematoma and fluid collection: clinical characteristics and management.

INTRODUCTION: Benign extracerebral fluid collection (bECFC) can be complicated by subdural hematoma (SDH) or subdural fluid collection (SDFC). The etiology, natural history, and management strategy for SDH/SDFC in bECFC are not fully understood. We retrospectively reviewed the cases of bECFC patients complicated with SDH/SDFC and tried (1) to confirm the fact that bECFC children are vulnerable to SDH/SDFC, (2) to investigate the clinical significance of 'trauma history' witnessed by a caregiver, and (3) to determine optimal management for them. METHOD: Among 213 bECFC patients identified from January 2000 to August 2015, 20 patients (male:female = 14:6; median age, 6.5 months; range 1-16 months) complicated by SDH/SDFC documented with brain imaging were evaluated for their clinical manifestations, radiologic features, and management outcomes. The median follow-up period was 9.5 months. They were divided into two groups (traumatic group versus non-traumatic group) according to whether objective radiologic evidence of head injury was present or not, and the two groups were analyzed for any clinical differences between them. We also evaluated the clinical significance of witnessed traumatic events by caregivers as an additional independent variable in the analysis. RESULTS: The incidence of SDH/SDFC in bECFC patients was 9.4% (20/213) in our data. In a comparative analysis, the traumatic group is more likely to have 'acute' stage SDH, whereas the non-traumatic group is more likely to have 'chronic' stage SDH. The trauma history witnessed by caregivers did not show clinical significance in the data analysis when included as an independent variable. The prognosis of SDH/SDFC in bECFC patients was favorable without surgery in most of patients regardless of whether the patient has evidence of head trauma or not. CONCLUSION: Benign ECFC is vulnerable to SDH/SDFC development. For the bECFC patients complicated by SDH/SDFC, the trauma history witnessed by a caregiver did not show any clinical significance. A 'wait and watch' strategy is sufficient for the management of SDH/SDFC in bECFC patients.

Ultrasonographic features differentiating thyroglossal duct cysts from dermoid cysts.

PURPOSE: The purpose of this study was to identify ultrasonographic features that can be used to differentiate between thyroglossal duct cysts (TGDCs) and dermoid cysts (DCs). METHODS: We searched surgical pathology reports completed between January 2004 and October 2015 and identified 66 patients with TGDCs or DCs who had undergone preoperative ultrasonography. The ultrasound images were reviewed by two radiologists who were blinded to the pathological diagnosis. They evaluated the following parameters: dimensions, shape, margin, location in relation to the midline, level in relation to the hyoid bone, attachment to the hyoid bone, the depth of the lesion in relation to the strap muscles, internal echogenicity, internal echogenic dots, multilocularity, the presence of a longitudinal extension into the tongue base, posterior acoustic enhancement, the presence of internal septae, and intralesional vascularity. RESULTS: There were 50 TGDCs and 16 DCs. TGDCs were significantly more likely than DCs to have an irregular shape, an ill-defined margin, attachment to the hyoid bone, an intramuscular location, heterogeneous internal echogenicity, multilocularity, and longitudinal extension into the tongue base. CONCLUSION: Ultrasound findings may inform the differential diagnosis between TGDCs and DCs.

Growing Cyst-Like White Matter Lesions in Children With Neurofibromatosis Type 1.

BACKGROUND: Neurofibromatosis type 1 (NF1) is an autosomal dominant disease with prominent neurocutaneous manifestations. The most common intracranial imaging finding of NF1 on brain magnetic resonance imaging (MRI) is the high-signal intensity foci without a mass effect or growth in size. PATIENT DESCRIPTION: We describe two children with NF1 in whom brain MRI showed growing cystic lesions and adjacent white matter signal abnormalities, which were confirmed as non-neoplastic cystic degeneration and reactive gliosis. CONCLUSION: Growing cyst-like white matter lesions can be seen on serial brain MRI in children with NF1. Reactive gliosis with cystic degeneration could be a pathogenic basis of these cystic lesions.

Image quality and radiation dose of brain computed tomography in children: effects of decreasing tube voltage from 120 kVp to 80 kVp.

BACKGROUND: Computed tomography (CT) has generated public concern associated with radiation exposure, especially for children. Lowering the tube voltage is one strategy to reduce radiation dose. OBJECTIVE: To assess the image quality and radiation dose of non-enhanced brain CT scans acquired at 80 kilo-voltage peak (kVp) compared to those at 120 kVp in children. MATERIALS AND METHODS: Thirty children who had undergone both 80- and 120-kVp non-enhanced brain CT were enrolled. For quantitative analysis, the mean attenuation of white and gray matter, attenuation difference, noise, signal-to-noise ratio, contrast-to-noise ratio and posterior fossa artifact index were measured. For qualitative analysis, noise, gray-white matter differentiation, artifact and overall image quality were scored. Radiation doses were evaluated by CT dose index, dose-length product and effective dose. RESULTS: The mean attenuations of gray and white matter and contrast-to-noise ratio were significantly increased at 80 kVp, while parameters related to image noise, i.e. noise, signal-to-noise ratio and posterior fossa artifact index were higher at 80 kVp than at 120 kVp. In qualitative analysis, 80-kVp images showed improved gray-white differentiation but more artifacts compared to 120-kVp images. Subjective image noise and overall image quality scores were similar between the two scans. Radiation dose parameters were significantly lower at 80 kVp than at 120 kVp. CONCLUSION: In pediatric non-enhanced brain CT scans, a decrease in tube voltage from 120 kVp to 80 kVp resulted in improved gray-white matter contrast, comparable image quality and decreased radiation dose.

eIF2B-related multisystem disorder in two sisters with atypical presentations.

BACKGROUND: Vanishing white matter disease (VWM) is a chronic progressive leukoencephalopathy that is characterized by cerebellar ataxia and spasticity, together with cystic degeneration of the cerebral white matter as evidenced by brain magnetic resonance imaging (MRI). Here, we report two sisters with EIF2B2 variants, who presented with delayed development and failure to thrive before 1 year of age, developed cataracts, and showed diffuse leukoencephalopathy. CASE PRESENTATION: The index case had a history of hepatomegaly and intermittent vomiting after upper respiratory infection at 11 months of age. Her older brothers had died at an early age, one with similar symptoms and the other because of septic shock. Her older sister had similar presenting symptoms; she later suffered from both cataracts and primary amenorrhea, but showed neurological improvement. Her follow-up MRIs (at 21 years of age) revealed progressive diffuse brain atrophy with leukoencephalopathy, without cystic rarefaction. Whole-exome sequencing of the index case revealed the presence of the compound heterozygous variants, Val85Glu and Met226Lys in EIF2B2. The affected sister had the same compound heterozygous variants, and their unaffected parents were heterozygous carriers of each variant. CONCLUSIONS: This study expanded the clinical and genetic spectrum of VWM with EIF2B2 variants. It would be better to consider VWM as an eIF2B-related multisystem disorder, not just as a neurological disorder, on the basis that this is a family of housekeeping genes that affect multiple organs.

Imaging findings of Kaposiform Hemangioendothelioma in children.

PURPOSE: Kaposiform hemangioendothelioma (KHE) is a rare, aggressive vascular tumor that typically occurs during infancy or early childhood. Though several case reports have discussed the imaging findings of KHE, larger comprehensive studies are lacking. The purpose of this study was to evaluate the imaging findings of KHE in children. MATERIALS AND METHODS: A total of twelve cases of pathologically proven KHE were collected by searching our institution's pathology database for children diagnosed between January 2004 and April 2016 (6 male, 6 female; median age: 3 months; age range 7days - 18 years). CT (n=7) and MRI (n=9) findings were retrospectively evaluated. The location, morphology, enhancement, and growth pattern were analyzed. RESULTS: KHEs involved various locations: superficial or deep soft tissue of the extremities (n=4); abdomen (n=3; 2 cases, pancreas; 1 case, small bowel), neck and mediastinum (n=1); chest wall, diaphragm, and pericardium (n=1); abdominal wall (n=1); and head (IAC, CP angle) (n=2). Eight of 10 cases (80%) with CT/MR findings were locally invasive and involved two or more adjacent organs. Three cases presented as well-defined solid masses, and seven were associated with infiltrative lesions of the surrounding areas with (n=4) or without definite solid regions (n=3). In nine patients with MRI, all KHEs were heterogeneous and hyperintense to muscles on T2-weighted images (T2WI), while four KHEs consisted of some regions that were nearly isointense to muscle. Eight of the 10 cases with imaging exhibited heterogeneous intense enhancement, while only one demonstrated mild enhancement. Signal voids (n=2), engorged vessels (n=1), calcification (n=3), hemorrhage (n=1), or bone changes (n=4) were infrequently observed. Four patients (33%) had Kasabach-Merritt phenomenon, and recurrence was observed in two cases. CONCLUSION: KHEs occurred in various locations, affected mostly infants, and generally exhibited intense heterogeneous enhancement. In more than half of the included cases, KHEs were highly infiltrative and locally invasive with ill-defined margins. Awareness of these features should prompt radiologists to include KHE in the differential diagnosis for pediatric masses.

Intestinal malrotation in patients with situs anomaly: Implication of the relative positions of the superior mesenteric artery and vein.

PURPOSE: To assess the usefulness of the relative position of the superior mesenteric artery (SMA) and superior mesenteric vein (SMV) in diagnosing intestinal malrotation in situs anomaly. MATERIALS AND METHODS: From January 2004 to April 2015, 33 patients with situs anomalies were enrolled in this study who underwent abdominal USG, CT or MRI as well as upper gastrointestinal series (UGIS) or surgery: situs inversus (n=16), left isomerism (n=10), and right isomerism (n=7); age 21.2±23.2years (mean±standard deviation), range 0-72 years. The intestinal malrotation was confirmed with UGIS and/or operation in 16 patients. Relative positions of the SMV to the SMA were classified into four groups by reviewing abdominal USG, CT, or MRI: right sided, left sided, ventral sided, and dorsal sided. The incidence of malrotation was analyzed for each group. RESULTS: In 16 patients with situs inversus, there was reversed SMA-SMV relationship: left sided (n=11) or ventral sided (n=5). One situs inversus patient with ventral sided SMV had intestinal malrotation (6.25%). 17 patients with situs ambiguus showed various SMA-SMV relationships (ventral sided, n=7; left sided, n=5; right sided, n=4; dorsal sided, n=1). Among them, 15 patients (88.2%) had intestinal malrotation. Two patients with normal rotation had either right sided or dorsal sided SMV. CONCLUSION: Situs ambiguus was commonly associated with intestinal malrotation with a variable SMA-SMV relationship. Reversal of the mesenteric vascular relationship was observed in situs inversus with normal rotation, not excluding the possibility of intestinal malrotation.

Ultrasonography evaluation of infants with Alagille syndrome: In comparison with biliary atresia and neonatal hepatitis.

OBJECTIVE: To evaluate the ultrasonography (US) features of Alagille syndrome (ALGS), as compared with biliary atresia (BA) or neonatal hepatitis (NH). METHODS: Our study included 23 ALGS, 75 BA and 70 NH patients. The initial US images were retrospectively reviewed for gallbladder (GB) morphology with systemic classification, GB length and luminal area, presence of triangular-cord (TC) sign and hypertrophied hepatic-artery. The presence of anomalies associated with ALGS was evaluated. The diagnostic values of each finding and their combinations were evaluated. RESULTS: Both ALGS (57%) and BA (79%) were more frequently associated with abnormal GB shapes than NH (19%, all P<0.001). The short and small GBs were more frequently observed in ALGS and BA than in NH (all P<0.001). None in the ALGS and NH showed TC sign, while 41% in the BA did (all P<0.001). Hypertrophied hepatic-artery was noted less frequently in both ALGS (13%) and NH (14%) than in BA (83%, all P<0.001). The combination of US criteria with associated anomalies increased the positive-predictive-value for ALGS. CONCLUSION: Abnormal shaped GB with absence of the TC sign and hypertrophied hepatic-artery and presence of associated anomalies can be a differential point of ALGS.

Free-Breathing Radial 3D Fat-Suppressed T1-Weighted Gradient-Echo Sequence for Contrast-Enhanced Pediatric Spinal Imaging: Comparison With T1-Weighted Turbo Spin-Echo Sequence.

OBJECTIVE: The purpose of this study was to compare free-breathing radially sampled 3D T1-weighted gradient-echo acquisitions (radial volumetric interpolated breath-hold examination [VIBE]) with a T1-weighted turbo spin-echo (TSE) sequence for contrast-enhanced spinal imaging of children with CNS tumors. MATERIALS AND METHODS: Twenty-eight consecutively registered children with CNS tumors underwent evaluation of leptomeningeal seeding with 1.5-T MRI that included both radial VIBE and T1-weighted TSE sequences. For qualitative analysis, overall image quality; presence of motion, CSF flow, and radial artifacts; and lesion conspicuity were retrospectively assessed with scoring systems. The signal-intensity uniformity of each sequence was evaluated for quantitative comparison. The acquisition times for each sequence were compared. RESULTS: Images obtained with the radial VIBE sequence had a higher overall image quality score than did T1-weighted TSE images (3.61 ± 0.73 vs 2.80 ± 0.69, p < 0.001) and lower motion artifact (0.82 ± 0.43 vs 1.29 ± 0.56, p = 0.001) and CSF flow artifact (0 vs 1.68 ± 0.67, p < 0.001) scores. Radial artifacts were found only on radial VIBE images (1.36 ± 0.31 vs 0, p < 0.001). In 13 patients with spinal seeding nodules, radial VIBE images showed greater lesion conspicuity than did T1-weighted TSE images (4.23 ± 0.52 vs 2.47 ± 0.57, p = 0.005). Radial VIBE images had diminished signal-intensity variation compared with T1-weighted TSE images in air, spine, and muscle (p < 0.01). The mean acquisition times were not significantly different between the two sequences (p = 0.117). CONCLUSION: For pediatric spinal imaging, radial VIBE images had better image quality and lesion conspicuity and fewer CSF and respiratory motion artifacts than did T1-weighted TSE images in a similar acquisition time.

Early imaging findings in germ cell tumors arising from the basal ganglia.

BACKGROUND: It is difficult to diagnosis early stage germ cell tumors originating in the basal ganglia, but early recognition is important for better outcome. OBJECTIVE: To evaluate serial MR images of basal ganglia germ cell tumors, with emphasis on the features of early stage tumors. MATERIALS AND METHODS: We retrospectively reviewed serial MR images of 15 tumors in 14 children and young adults. We categorized MR images of the tumors as follows: type I, ill-defined patchy lesions (<3 cm) without cyst; type II, small mass lesions (<3 cm) with cyst; and type III, large lesions (≥3 cm) with cyst. We also assessed temporal changes of the MR images. RESULTS: On the initial images, 8 of 11 (73%) type I tumors progressed to types II or III, and 3 of 4 (75%) type II tumors progressed to type III. The remaining 4 tumors did not change in type. All type II tumors (5/5, 100%) that changed from type I had a few tiny cysts. Intratumoral hemorrhage was observed even in the type I tumor. Ipsilateral hemiatrophy was observed in most of the tumors (13/15, 87%) on initial MR images. As tumors grew, cystic changes, intratumoral hemorrhage, and ipsilateral hemiatrophy became more apparent. CONCLUSION: Early stage basal ganglia germ cell tumors appear as ill-defined small patchy hyperintense lesions without cysts on T2-weighted images, are frequently associated with ipsilateral hemiatrophy, and sometimes show microhemorrhage. Tumors develop tiny cysts at a relatively early stage.