Antenatal Diagnosis of Iniencephaly: Sonographic and MR Correlation: A Case Report

Iniencephaly is an uncommon and fatal neural tube defect involving the occiput and inion, this occurs together with rachischisis of the cervical and thoracic spine, and retroflexion of the head. We report the ultrasound (US) and magnetic resonance (MR) imaging findings of a case of iniencephaly with clubfeet and arthrogryposis. The diagnosis of iniencephaly is easy to make on ultrasound due to the typical star-gazing fetus. However, the details of the fetal brain and spinal cord may not be adequately delineated on US. We found MR imaging to be superior for depicting central nervous system abnormalities. MR imaging has evolved as an imaging modality and it is complementary to fetal US, yet US remains the screening modality of choice.

Sonographic Measurement of the Fetal Cerebellar Vermis

PURPOSE: To obtain a reference value for fetal vermian size measured with sonography. MATERIALS AND METHODS: A prospective study of normal singleton pregnancies was performed. The fetal vermian width and anterior-posterior (AP) diameter were measured with axial image by transabdominal sonography between 18 and 37 weeks of gestation in 264 singleton fetuses. Linear regressions of the vermian width and AP diameter as a function of gestational age (GA), biparietal diameter (BPD), head circumference (HC) and transcerebellar diameter (TCD) were calculated. RESULTS: Adequate vermis measurements were obtained in 264 fetuses. Vermian width was correlated well with GA (r2 = 0.851), BPD (r2 = 0.824), HC (r2 = 0.844) and TCD (r2 = 0.859). AP diameter was also correlated with GA (r2 = 0.826), BPD (r2 = 0.843), HC (r2 = 0.814) and TCD (r2 = 0.836). All the correlation coefficients were highly statistically significant (p < 0.001). Nomograms of the vermian width and AP diameter according to the gestational age were obtained. CONCLUSION: Measured fetal vermian size was correlated well with GA which confirmed the usefulness of the rermian size as a reference value for the assessment of vermian development.

Congenital Cytomegalovirus Infection of the Brain: MR Imaging and Ultrasonographic Findings of Paraventricular Cysts

PURPOSE: Although the neuroradiological findings of congenital cytomegalovirus (CMV) infection are well known, little has been reported concerning the imaging findings of paraventricular cysts occurring in patients with cytomegalovirus infection involving the brain. The purpose of this study is to describe the features of paraventricular cysts observed at MRI and ultrasonography. MATERIALS AND METHODS: MR and ultrasonographic studies of ten patients with congenital cytomegalovirus infections involving the brain were retrospectively reviewed. Diagnosis was confirmed by positive culture of the virus in urine (n=4), the presence of CMV Ig G antibody (n=4), or positive CMV Ig M antibody (n=2), and on the basis of characteristic MR imaging findings. Initial MRI in all patients and initial ultrasonography in four of five with paraventricular cysts were performed. Three patients underwent follow-up MRI and ultrasonography for the evaluation of cystic change, and the size, location, bilaterality and morphology of the cysts were evaluated. RESULTS: Bilateral paraventricular cysts averaging 15 (range. 10-23) mm in size were found in five of the ten patients (50%). They were adjacent to the foramen of Monro in three cases, the occipital horn in one, and the temporal horn in one. MR imaging showed that the fluid content of all cysts was of similar signal intensity to cerebrospinal fluid (T1-WI, hypointense; T2-WI, hyperintense). The ultrasonographic findings varied: there was one pure cyst and one with a thick wall and septations, and two contained complex fluid. In three patients, follow up MRI and ultrasonography showed that the cysts disappeared after 4-23 months. CONCLUSION: Although paraventricular cysts may appear at MRI to be purely cystic, ultrasonography may indicate that their contents are more complex, or that septations are present.

Congenital Glioblastoma Multiforme: A Case Report

Congenital glioblastoma multiforme is relatively rare accounting for 2-9% of all congenital brain tumors. We deseribe a case of congenital glioblastoma multiforme which occurred in the lateral ventricle. T1-weighted images revealed high signal intensity, with areas of internal low signal intensity, while T2-weighted images showed low signal intensity with focal internal high-signal portions. Post-contrast T1-weighted images depicted a lateral ventricular mass which extended to adjacent brain parenchyme and had a serpentine signal void representing internal vessel.

Comparison of Intraventricular Hemorrhagic Findings in Preterm Infants Between Brain Ultrasonogram and Magnetic Resonance Imaging at Discharge

PURPOSE: It has been customary to perform brain ultrasonogram (brain US) for the early detection of intraventricular hemorrhage (IVH) during intensive care of neonates. On the other hand magnetic resonance imaging (MRI) has been greatly restrictioned due to its complicated procedures. This study was conducted to identify changes in neonates' brain structure and to gain basic data for the long-term follow-up of neurologic sequelae in the future. For this purpose, the findings obtained from both brain US performed within one postnatal week and MRI at the time of discharge were compared and analysed. METHODS: Brain US within one postnatal week and MRI at discharge were carried out on 67 neonates who were discharged from the neonatal intensive care unit of Fatima Hospital from July 01, 1996 to June 30, 1998. We compared and analysed IVH found in the brain US, and focal parenchymal hemorrhage, periventricular leukomalacia (PVL), basal ganglia hemorrhage, and encephalomalacia revealed the MRI performed at discharge. RESULTS: It was found that out of 67 cases from the brain US, there were 13 with IVH of Grade l & ll, 11 with IVH of Grade lll or higher, one with focal parenchymal hemorrhage, and three with PVL. Also the MRI found seven with focal parenchymal hemorrhage, one with basal ganglia hemorrhage, six with PVL, three with encephalomalacia, and one with ventricular dilatation. CONCLUSION: For infants with IVH of Grade lll or higher, MRI performed at discharge is considered to be very useful in identifying structural parenchymal abnormality and the presence or absence of its associated lesions as well as in carrying out long-term follow-up.

Imaging of the Ventriculoperitoneal Shunt-Related Complications in Infants and Children With Hydrocephalus

PURPOSE: To evaluate the frequency and imaging findings of various ventriculo-peritoneal shunt-relatedcomplications in pediatric patients with hydrocephalus. MATERIALS AND METHODS: We retrospectively reviewed 246plain radiographs, three shuntograms, 53 ultrasounds, 133 CT scans, and 24 MR images obtained before and after theventriculo-peritoneal shunt procedure in 33 pediatric patients with hydrocephalus. Using preoperative images, theetiology of the hydrocephalus was assessed. Changes in the size and shape of the ventricles, the location andcontinuity of shunt apparatus, and the presence of any abnormal enhancement, hemorrhage, edema or tissue loss, orother findings of complications, were analyzed on postoperative images; the frequency and imaging findings ofshunt-related complications such as shunt malfunction, infection, hemorrhage or isolated ventricle, andcomplications caused by overdrainage, were thus evaluated. The frequency of such complications was analyzedaccording to the etiology of the hydrocephalus, and in addition, medical records were reviewed and correlated withimaging findings. RESULTS: In 18 of the 33 patients(54%), a total of 31 complications was detected. These werepresent in four of five cases (80%) of hydrocephalus caused by meningitis and ventriculitis, seven of twelve (58%)intraventricular hemorrhage, two of four (50%) unknown cases, three of nine (33%) congenital malformations, one oftwo (50%) tumors, and one (100%) congenital infection. Shunt malfunction was most common(n=15), and wasaccompanied by findings of enlarged ventricles, periventricular and peritubal edema, and abnormal location of theshunt tube. Symptoms and signs of increased intracranial pressure were also noted. Subdural hemorrhage andinfection were present infour cases each;findings of infection were enhancement of the ventricular wall, meninges,and parenchyma, as well as sonographically noted intraventricular septation and increased ventricular wall echo.Isolated lateral ventricle (n=4) or 4th ventricle (n=1) was persistently distended in spite of the presence of ashunt tube within the other ventricle. Collapsed ventricles, thick calvarium, and symptoms of increasedintracranial pressure were helpful in the diagnosis of slit ventricle syndrome(n=1). Immediate postoperativeintraventricular and parenchymal hemorrhage were noted in one case each. CONCLUSION: Shunt-related complicationswere found on postoperative images in 54% of pediatric patients with hydrocephalus; the frequency was highest incases of hydrocephalus caused by infection. Shunt malfunction occurred most frequently and each complication hadvarious imaging findings. For the diagnosis of post-operative shunt-related complication, continuous follow-upstudies are therefore necessary.

Imaging of the Ventriculoperitoneal Shunt-Related Complications in Infants and Children With Hydrocephalus

PURPOSE: To evaluate the frequency and imaging findings of various ventriculo-peritoneal shunt-relatedcomplications in pediatric patients with hydrocephalus. MATERIALS AND METHODS: We retrospectively reviewed 246plain radiographs, three shuntograms, 53 ultrasounds, 133 CT scans, and 24 MR images obtained before and after theventriculo-peritoneal shunt procedure in 33 pediatric patients with hydrocephalus. Using preoperative images, theetiology of the hydrocephalus was assessed. Changes in the size and shape of the ventricles, the location andcontinuity of shunt apparatus, and the presence of any abnormal enhancement, hemorrhage, edema or tissue loss, orother findings of complications, were analyzed on postoperative images; the frequency and imaging findings ofshunt-related complications such as shunt malfunction, infection, hemorrhage or isolated ventricle, andcomplications caused by overdrainage, were thus evaluated. The frequency of such complications was analyzedaccording to the etiology of the hydrocephalus, and in addition, medical records were reviewed and correlated withimaging findings. RESULTS: In 18 of the 33 patients(54%), a total of 31 complications was detected. These werepresent in four of five cases (80%) of hydrocephalus caused by meningitis and ventriculitis, seven of twelve (58%)intraventricular hemorrhage, two of four (50%) unknown cases, three of nine (33%) congenital malformations, one oftwo (50%) tumors, and one (100%) congenital infection. Shunt malfunction was most common(n=15), and wasaccompanied by findings of enlarged ventricles, periventricular and peritubal edema, and abnormal location of theshunt tube. Symptoms and signs of increased intracranial pressure were also noted. Subdural hemorrhage andinfection were present infour cases each;findings of infection were enhancement of the ventricular wall, meninges,and parenchyma, as well as sonographically noted intraventricular septation and increased ventricular wall echo.Isolated lateral ventricle (n=4) or 4th ventricle (n=1) was persistently distended in spite of the presence of ashunt tube within the other ventricle. Collapsed ventricles, thick calvarium, and symptoms of increasedintracranial pressure were helpful in the diagnosis of slit ventricle syndrome(n=1). Immediate postoperativeintraventricular and parenchymal hemorrhage were noted in one case each. CONCLUSION: Shunt-related complicationswere found on postoperative images in 54% of pediatric patients with hydrocephalus; the frequency was highest incases of hydrocephalus caused by infection. Shunt malfunction occurred most frequently and each complication hadvarious imaging findings. For the diagnosis of post-operative shunt-related complication, continuous follow-upstudies are therefore necessary.

Prominent Extraaxial CSF Space on Cranial Ultrasound in Infants: Correlation with Neuro d evelopmental Outcome

PURPOSE: To determine the clinical significance of prominent extra-axial CSF space (EACSFS) in infants, as seen on cranial ultrasound. MATERIALS AND METHODS: Between March 1996 and November 1997, all infants who had undergone head ultrasound at our institution and were found to have prominent EACSFS were evaluated. The width of the interhemispheric fissure was measured at three locations at the level of the frontal horn, body and atrium of the lateral ventricles. The depth of the CSF space over the convexity was also measured. The average of these measurements was calculated and each patient was assigned to one of three groups: mild, moderate, or marke d. Ultrasound findings were evaluated for other associated abnormalities. Clinical neurodevelopment was evaluated by a pediatric neurologist, and ultrasound and neurodevelopmental findings were correlated. RESULTS: Prominent EAC S FS was found in 153 patients, and neurodevelopmental evaluation up to a corrected age of 9 months was available in 133. One hundred and eight of 117 infants with normal neurodevelopment had no other associated abnormality (n=81), or abnormality associated only with grade I subependymal hemorrhage or cyst (n=27). Twe l ve of 16 infants with an abnormal neurodevelopmental outcome had major abnormalities including PVL, grade IV hemorrhage, and marked ventriculomegaly. CONCLUSION: Prominent EAC S FS alone does not appear to be clinically significant. An abnormal neurodevelopmental outcome is associated with major abnormalities seen on ultrasound. Follow-up examination for prominent EAC S FS is not indicated unless the associated abnormality requires further evaluation.

Radiologic Findings of Sinus Pericranii

Sinus pericranii is a rare vascular anomaly consisting of abnormal venous communication between intra- andextracranial circulation. We report one case, confirmed by surgery, and describe the radiological findings ofDoppler ultrasonography, CT and MR imaging.

Early Periventricular Leukomalacia: MRI and Ultrasonographic Correlation on First one Month of Life

PURPOSE: To compare the findings of early periventricular leukomalacia on MR imaging and on US. MATERIALS AND METHODS: MR imaging was performed in 17 neonates in whom well-demarcated increased periventricular echogenicity was seen on sonography. One more patient was included during the same period because MR imaging of this patient showed a periventricular lesion not suspected on previous US. Initial sonography was performed within 6 days of birth and was followed up between one week and one month later. MR images were obtained within the first month of life. RESULTS: Twelve of 17 neonates showed abnormal periventricular signal intensities on MR imaging. Follow up sonography revealed cystic changes in two cases and heterogeneous hyperechogenicities in three. All patients except the two with cystic changes showed normal periventricular echogenicity on final sonography, On MR imaging,11 cases showed multifocal periventricular increased signals on T1-weighted images, and two cases showed mainly decreased signals representing cysts. Positive findings were more evident on T1-weighted than on T2-weighted image. CONCLUSION: on T1-weighted imaging, the characteristic finding of early periventricular leukomalacia was multifocal periventricular hyper or hypointensities, and hyperintense lesions were more common than hypointense. In the diagnosis of early noncystic periventricular leukomalacia, MR imaging was more objective than US.