In-111 DTPA cisternographic demonstration of magna cisterna magna.
Explore the source record for details and available documents.
Aged↗
SEARCH · Search PubMed
Results for “CISTERNA MAGNA”
Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
The fetal cisterna magna.
Antenatal sonography routinely images the fetal cisterna magna. The identification of a prominent cisterna magna on a routine antenatal sonogram performed for obstetric indications may raise the question of a congenital posterior fossa lesion. To delineate the size of the fetal cisterna magna, standardized measurements for the midsagittal depth of the cisterna magna were prospectively obtained on 219 consecutive antenatal sonograms in fetuses of 15 menstrual weeks or more. The cisterna magna depth measured 5 +/- 3 mm; the largest cisterna magna measured 10 mm in depth. In the absence of other findings to suggest a posterior fossa lesion, a prominent cisterna magna is unlikely to be clinically significant.
Brain↗
Effacement of the fetal cisterna magna in association with myelomeningocele.
The cisterna magna is effaced in association with myelomeningocele. The authors retrospectively investigated the size of the fetal cisterna magna as a predictor of fetal myelomeningocele in 67 pregnant women (17-38 menstrual weeks) referred for prenatal sonography because of an elevated serum alpha-fetoprotein level (n = 61) or a suspicion of fetal ventriculomegaly on previously obtained sonograms (n = 6). Twenty fetuses had myelomeningocele, 14 had isolated ventriculomegaly, and 33 were normal. A normal-sized cisterna magna (range, 4-9 mm in depth) was present in all normal fetuses. In 19 of 20 fetuses with myelomeningocele, the views of the posterior fossa were adequate, and in each of these the cisterna magna was effaced (n = 18) or very small (n = 1). The cisterna magna was effaced in five of 13 (38%) fetuses with isolated ventriculomegaly in whom the posterior fossa was adequately imaged. Although effacement of the cisterna magna is a nonspecific finding, the high negative predictive value of this sign is useful during routine screening of the fetal neural axis.
Cisterna Magna↗
Clinical significance of isolated enlargement of the cisterna magna (> 10 mm) on prenatal sonography.
Enlargement of the cisterna magna has been reported to be associated with aneuploidy. In prior studies of cisterna magna enlargement, however, those fetuses with abnormal chromosomes have had other sonographic abnormalities in addition to a large cisterna magna. Our goal was to assess the clinical significance of the isolated finding of a cisterna magna measuring more than 10 mm in anteroposterior dimension on a prenatal sonogram. We retrieved all prenatal sonograms performed at our institution between 1989 and 1996 in which an enlarged cisterna magna was the only sonographic abnormality. Cases were included in our study if the cisterna magna measured more than 10 mm in the appropriate plane and the fetal survey was otherwise normal, including normal cerebellar size and morphology. Pregnancy outcome and postnatal follow-up were obtained in each case. Fifteen cases comprised our study population. In all 15 fetuses, the enlarged cisterna magna was first seen in the third trimester (gestational age range, 26 to 37 weeks). The cisterna magna ranged from 11 to 19 mm in size (mean, 12.9 mm). All 15 pregnancies resulted in phenotypically normal liveborn infants. All the mother and infants had short hospital stays (1 to 4 days), and the infants were normal at discharge. Longer follow-up was available in eight cases (range, 2 to 69 months), and all eight of these infants were normal. Our results suggest that isolated enlargement of the cisterna magna to more than 10 mm is associated with normal pregnancy and neonatal outcome.
Cisterna Magna↗
The mega cisterna magna.
Eleven cases of enlarged cisterna magna were found in a series of 3000 computerized tomography scans. We believe mega cisterna magna by itself is not related to any specific symptoms and may not require further study or treatment.
Adolescent↗
Transvaginal sonographic measurement of cisterna magna in fetuses with abnormal karyotype.
The fetal cisterna magna was measured by transvaginal sonography in early pregnancy in 525 pregnant women at increased genetic risk in order to test whether the measurements thus obtained afforded a sonographic marker for abnormal fetal karyotype. The measurements of the cisterna magna increased as pregnancy progressed and showed a good linear correlation with gestational age (r = 0.616; p < 0.001). Chromosome abnormalities were found in 23 fetuses. In all these cases, the cisterna magna measurements were normal, and no differences were observed between fetuses with normal and abnormal karyotype in the different periods tested. While transvaginal sonographic measurement of the cisterna magna is easy to perform in early pregnancy, it is a poor screening test for the detection of abnormal fetal karyotypes.
Aneuploidy↗
Biometry of the fetal cisterna magna: estimates of the ability to detect trisomy 18.
Measurements of the fetal cisterna magna were obtained from a prospective sample of patients undergoing diagnostic obstetric ultrasound examinations. These normal measurements were then compared to a retrospective sample of ultrasound scans from fetuses with the diagnosis of trisomy 18 by amniocentesis. The fetal cisterna magna increases in size throughout pregnancy. The sample from fetuses with trisomy 18 was different and had a higher rate of small and large cisterna magnas. After the two samples were mixed, it was determined that a cut-off of 2.5 standard deviations for the fetal cisterna magna would give a sensitivity of 26.3%, specificity of 99.1%, positive predictive value of 50.0% and negative predictive value of 97.6% for trisomy 18. The probability that a fetal cisterna magna of abnormal size will predict trisomy 18 in an early second-trimester ultrasound examination with the 2.5 standard deviation cut-off was estimated at 0.019. A fetal cisterna magna that is of abnormal size appears to be of diagnostic value in identifying the fetus with trisomy 18, but its sensitivity is low.
Adult↗
Ultrasonographic appearance of the mega cisterna magna in the newborn.
The mega cisterna magna is a congenital developmental malformation which in the majority of instances is symptomless and does not require further study or surgical treatment. However, differential diagnosis with other cerebellar diseases is often necessary especially in newborn infants. Ultrasonographic recognition of the mega cisterna magna in a newborn infant is reported. The reported case demonstrates the usefulness of the ultrasonographic technique in the study of the posterior cranial fossa abnormalities of newborn infants.
Cisterna Magna↗
The cisterna magna septa: vestigial remnants of Blake's pouch and a potential new marker for normal development of the rhombencephalon.
OBJECTIVE: The purpose of this study was to show the normal sonographic embryologic anatomy of the cisterna magna septa, fourth ventricle, and cerebellar vallecula at various stages of development and our experience with their variable appearance in multiple planes and to discuss the probable relationship between the cisterna magna septa, Dandy-Walker continuum, mega cisterna magna, and persistent Blake's pouch. METHODS: Retrospective and prospective selection of examples of cisterna magna septa was performed over approximately a 12-month period. Standard and nonstandard imaging planes were adopted as necessary. RESULTS: The septa are typically seen inferoposterior to the cerebellar vermis, usually straight and parallel, arising at the cerebellovermian angle and coursing posteriorly to the occipital bone. The cisterna magna septa become contiguous with the roof of the fourth ventricle inferior to the cerebellar vermis. The cerebrospinal fluid space enclosed between the cisterna magna septa is in direct contiguity with the fourth ventricle via the vallecula and is always completely anechoic because it develops intra- and not extra-axially. CONCLUSIONS: We propose that the cisterna magna septa represent the walls of Blake's pouch, a phylogenetic vestigial structure observed during ontogeny. Additionally, our observations support current opinion that a persistent Blake's pouch and mega cisterna magna represent (less severe) abnormalities within the Dandy-Walker continuum. The cisterna magna septa therefore are a marker of normal development of the roof of the rhombencephalon. Deviation from their normal appearances should prompt a closer assessment for associated abnormalities of the cerebellum, vermis, and brain stem by additional imaging in orthogonal planes with either sonography or magnetic resonance imaging.
Cisterna Magna↗
Meningioma within the cisterna magna without dural attachment. Case report.
A case of meningioma within the cisterna magna without dural attachment is reported. Meningiomas of the posterior fossa without dural attachment are very rare and have been classified in to: 1) intraventricular meningiomas; 2) meningiomas of the tela chorioidea; 3) meningiomas within the cisterna magna. Only two cases of meningiomas within the cisterna magna without dural attachment have been reported, one in 1923 and another in 1938. The case now reported was studied by angiography and magnetic resonance and operated with microsurgical technique. We describe neuroradiological and operative findings of this exceptional meningioma within the cisterna magna without dural attachment.
Cerebral Angiography↗
The neonatal cisterna magna: ultrasonic evaluation.
The normal topography of the region of the cisterna magna can be delineated by cranial ultrasound in neonates. Evaluation of this region requires ultrasonic imaging of the echodense occipital bone and the inferior vermis, as well as approximation of the plane of the foramen magnum. It also requires imaging of the anechoic cisterna magna and fastigium of the fourth ventricle. In order to appreciate subtle alterations in size and/or position of these structures, standardized measurements for the midsagittal height of the cisterna magna and the distance of the fastigium of the fourth ventricle from the plane of the foramen magnum were established. Normal values established by measurement in 59 patients were cisterna magna 4.52 +/- 1.29 mm and fastigium of the fourth ventricle 16.05 +/- 3.03 mm. These dimensions were demonstrated to be abnormally increased in posterior fossa arachnoid cysts, Dandy-Walker syndrome, and hydrocephalus.
Arachnoid↗
Mega cisterna magna: diagnosis using metrizamide computed tomographic cisternography.
The mega cisterna magna is one cause of a midline, extra-axial, posterior fossa cyst. The computed tomographic features and differential diagnosis of midline posterior fossa cystic structures are reviewed, and the clinical features of the mega cisterna magna are discussed. We describe a method of metrizamide cisternography and report a case of mega cisterna magna that was diagnosed by this technique.
Adult↗
Fetal central nervous system ventricle and cisterna magna measurements by magnetic resonance imaging.
OBJECTIVE: Our purpose was to evaluate the ventricular atria and cisterna magna in fetuses with and without suspected central nervous system (CNS) anomalies by magnetic resonance (MR). STUDY DESIGN: Measurements of the right and left ventricular atria and cisterna magna were obtained by MR in two groups: those with and without CNS anomalies. Published mean ultrasound measurements of the far field atrium were compared with MR. RESULTS: MR measurements were obtained in 23 fetuses without and 37 fetuses with CNS anomalies. Atrial measurements were independent of gestational age in healthy subjects. MR atrial widths were larger in abnormal compared with normal subjects (P <.05). The atrial cutoff value derived by 2 SDs above the mean with MR is 10 mm. MR cisterna magna measurements increased with gestational age (P =.005). CONCLUSION: The cutoff value for ventriculomegaly on MR is >10 mm. MR cisterna magna measurements are dependent on gestational age. Both ventricular atria and cisterna magna are readily measured with MR.
Brain↗
[A study of cisterna magna on brain computerized tomography in children].
Although many publications on cranial computerized tomography have been reported in recent years, very little attention has been directed to the cisterna magna (CM) and its variations. The size of the cisterna magna is still debatable and the criterion of the mega cisterna magna is obscure. We studied age distribution, clinical manifestations, and other CT findings in the children with enlarged cisterna magna. A consecutive series of 367 computerized tomographic scans were reviewed. We classified four classes according to the degree of enlargement of the cisterna magna: CM is undetectable; CM (-), CM is detectable at the level of sella turcica and the fourth ventricle; CM(+), CM extends upward at the level of suprasellar cistern and colliculus inferior; CM (+ +), and CM extends extensively at the level of the third ventricle and colliculus superior; CM (+ + +). We judged 55 CT scans (15%) to belong to CM (+ + +) class and 100 scans (27%) to CM (+ +) class. The greater part of children with CM (+ + +) were younger in contrast with CM (+ +), which distributed uniformly in every ages. Also we differentiated the patients into three groups from clinical manifestations as follows: patients with developmental delayed; group D, patients with organic neurological diseases; group N, patients with other diseases; group O. The ratio of group D is significantly higher in CM (+ + +) than that of other groups. No children had posterior fossa symptoms of mass effect and required treatment.(ABSTRACT TRUNCATED AT 250 WORDS)
Adolescent↗
[Lateral suboccipital puncture of the cisterna magna (author's transl)].
Lateral puncture of the cisterna magna cerebellomedullaris offers a more efficient conception of the lateral approach for the use of positive and negative contract medium in myelography and cisternography. The extracranial part of the cisterna magna cerebellomedullaris gives enough space to ensure the definite fixation of the needle without any major risk after puncture through the atlanto-occipital membrane. Positioning of the needles tip is possible without x-Ray control. Injury of the spinal cord is most unlikely to occur.
Cisterna Magna↗
Macro cisterna magna: a marker for maldevelopment of the brain?
Enlargement of the cisterna magna occurs in as many as 0.4% of reported patients and generally has been believed to represent a normal variant. Differentiation from Dandy-Walker malformations and other cystic structures has been emphasized. We reviewed 1,260 consecutive computed tomography reports in patients younger than 21 years of age and examined all scans in which enlargement of the cisterna magna was considered an isolated finding. Fourteen patients were identified (incidence: 1%). The primary reasons for obtaining computed tomographic scans included various clinical conditions but excluded symptoms indicative of posterior fossa disease. Developmental or neurologic abnormalities were present in 62% of these patients. Macro cisterna magna should not be dismissed as a normal variant, although the neurologic findings may not be specifically localized to the posterior fossa. This finding may be a marker for abnormal brain function most likely due to subtle disturbances in brain development.
Brain↗
Linear echoes in the fetal cisterna magna.
Linear echoes are seen in the fetal cisterna magna, (CM) on obstetrical sonography. These echoes often are paired, joining as they descend toward the base of the posterior fossa. Histologic correlation suggests that these echoes are most consistent with dural folds, which likely represent the inferior attachment of the falx cerebelli. A prospective series of 322 prenatal studies was performed in which the sonographer was asked to look for the linear echoes in the cisterna magna and image them. Linear echoes were identified in 84% of all fetuses studied. Identification of these echoes was dependent on CM size, in that they were seen less commonly when the CM was less than 3 mm in diameter. However, their identification was not dependent on gestational age. In addition, 18 fetuses with Dandy Walker cyst or Dandy Walker variant were evaluated and in 16 linear echoes were not seen. We conclude that recognition of normal anatomy within the fetal brain, specifically the fetal CM, is helpful for identifying abnormalities in the size of the CM, whether large or small.
Cisterna Magna↗
[Unusual extra-axial infra-tentorial localization of a cavernoma in the cisterna magna].
A case of an extra-axial cavernous angioma of the cisterna magna is described. The clinical presentation, radiographic features, treatment of that unusual location in the posterior fossa are discussed. The patient is a 31 years old man admitted for the sudden onset of occipital headache and instability. A CT scan demonstrated a slightly calcified lesion, minimally enhanced after intravenous injection of a contrast agent, located within the posterior fossa. A T2-weighted MR image showed a well circumscribed mass, located between medulla oblongata and left cerebellar tonsil, of mixed signal intensity surrounded by a rim of decreased signal intensity related to the presence of hemosiderin. Cerebral arteriography was normal. A medial suboccipital craniectomy was performed, with the patient in the ventral position, in which a 1.5 x 1 cm solid dark-red mass was encountered arising from the cisterna magna and was easily removed "en bloc". The operative extra-axial aspect of that lesion was evident excluding a medulla oblongata tumor protruding into the cisterna magna. Histologically, the lesion was a cavernous angioma consisting of numerous vascular channels with collagen fibrous walls filled with fibrin thrombi and hemosiderin. Few elastic fibers were found in vascular walls. The patient's post-operative course was unremarkable.
Adult↗