Spinal level of myelomeningocele lesion as a contributing factor in posterior fossa volume, intracranial cerebellar volume, and cerebellar ectopia

2013 ◽  
Vol 11 (2) ◽  
pp. 154-159 ◽  
Author(s):  
Kieron J. Sweeney ◽  
John Caird ◽  
Muhammad Taufiq Sattar ◽  
David Allcutt ◽  
Darach Crimmins

Object McLone and Knepper's unified theory of Chiari malformation Type II (CM-II) describes how the loss of CSF via the open posterior neuropore fails to create adequate distending pressure for the developing rhomboencephalic vesicle. The authors of the present article describe the relationship between the posterior fossa volume and intracranial cerebellar volume as being related to the distance from the obex of the fourth ventricle to the myelomeningocele lesion using a common mathematical model, the Hagen-Poiseuille law. Methods All newborns who required closure of a myelomeningocele at the authors' institution between 2008 and 2011 and who were between 4 weeks premature and 2 months, corrected gestational age, at the time of MRI were included in this study. Volumes and measurements were obtained from axial and sagittal T2-weighted MR images of the brain and spine. Results: A total of 56 newborn infants met the inclusion criteria. There was a direct linear relationship between both posterior fossa volume and cerebellar volume and the spinal level of the myelomeningocele lesion (p = 0.0012 and p = 0.0041, respectively). There was a negative linear relationship between the cerebellar descent, the spinal level of the lesion, and posterior fossa volume and cerebellar volume. These relationships strengthen in patients with no syringomyelia and are not significant in those groups with syringomyelia. The results of a 1-way ANOVA for the 3 groups did not reach significance. Conclusions Using a linear equation derived from the Hagen-Poiseuille law that describes pressure in the fourth ventricle as being directly related to the length of the central canal from the obex to the myelomeningocele lesion, the authors were able to explain the directly observed linear relation between posterior fossa volume, intracranial cerebellar volume, and cerebellar descent to the level of the spinal lesion. As this model assumes a uniform radius of the central canal they were able to validate this model when they observed a strengthening in relationships in the no syringomyelia group and statistically insignificant correlations in the groups with syringomyelia. They therefore propose that the spinal level of the lesion is one of the major determinants of posterior fossa volume, intracranial cerebellar volume, and cerebellar ectopia.

Neurosurgery ◽  
1984 ◽  
Vol 14 (6) ◽  
pp. 737-739 ◽  
Author(s):  
Kobayashi Hidenori ◽  
Kawano Hirokazu ◽  
Ito Haruhide ◽  
Hayashi Minoru ◽  
Yamamoto Shinjiro

Abstract A case of hemangioma calcificans in the 4th ventricle is reported. Skull x-ray films demonstrated a dense calcification in the posterior fossa. Computed tomography disclosed a hyperdense mass in the 4th ventricle. The clinical picture was of increased intracranial pressure due to obstructive hydrocephalus. An hemangioma calcificans in the 4th ventricle was removed successfully.


PEDIATRICS ◽  
1962 ◽  
Vol 29 (2) ◽  
pp. 295-302
Author(s):  
Bertil Palmgren

A description is given of incontinentia pigmenti, with special reference to the various clinical stages and the theories of the causes of the condition. One case seen in a girl is described. The case was characterized by a very severe vesicular stage and marked eosinophilia in the blood as well as in the skin lesions. Herpes simplex virus could be regularly demonstrated in fluid from fresh vesicles. The neutralization test for herpes simplex showed no increase in the antibody titer of the patient, while during the following months an increase in titer was noted in the mother. At 2 years of age the child was normally developed, apart from a somewhat retarded eruption of the decidous teeth.


PEDIATRICS ◽  
1952 ◽  
Vol 9 (5) ◽  
pp. 534-543
Author(s):  
LYTT I. GARDNER

Three cases of newborn tetany are described, pointing out the relationship between dietary phosphate load and the manifestations of this disease. An additional three newborn infants are described who showed other symptomatology than tetany in association with dietary phosphate load. [See Table 1 in Source Pdf]. Data concerning diet, cause of death and degree of parathyroid hyperplasia are tabulated in eight newborns who were found to have parathyroid hyperplasia at autopsy. Similar data are tabulated on eight newborns and five older children who were found to have normal parathyroid glands at autopsy. Several other factors possibly involved in newborn tetany and newborn parathyroid hyperplasia are discussed. The importance of measuring serum inorganic P in the differential diagnosis of neonatal distress is pointed out.


1982 ◽  
Vol 14 (2) ◽  
pp. 43-49
Author(s):  
Stephen E. Miller

The literature of industrial organization is replete with analyses of the relationship between seller concentration and market performance. Most researchers have hypothesized a continuous linear relationship between profitability and concentration and have estimated that relationship accordingly.


2011 ◽  
Vol 7 (1) ◽  
pp. 52-63 ◽  
Author(s):  
Suhas Udayakumaran ◽  
Naresh Biyani ◽  
David P. Rosenbaum ◽  
Liat Ben-Sira ◽  
Shlomi Constantini ◽  
...  

Object Trapped fourth ventricle (TFV) is a rare late complication of postinfectious or posthemorrhagic hydrocephalus. This entity is distinct from a large fourth ventricle because TFV entails pressure in the fourth ventricle and posterior fossa due to abnormal inflow and outflow of CSF, causing significant symptoms and signs. As TFV is mostly found in children who were born prematurely and have cerebral palsy, diagnosis and treatment options are a true challenge. Methods Between February 1998 and February 2007, 12 children were treated for TFV in Dana Children's Hospital by posterior fossa craniotomy/craniectomy and opening of the TFV into the spinal subarachnoid space. The authors performed a retrospective analysis of relevant data, including pre- and postoperative clinical characteristics, surgical management, and outcome. Results Thirteen fenestrations of trapped fourth ventricles (FTFVs) were performed in 12 patients. In 6 patients with prominent arachnoid thickening, a stent was left from the opened fourth ventricle into the spinal subarachnoid space. One patient underwent a second FTFV 21 months after the initial procedure. No perioperative complications were encountered. All 12 patients (100%) showed clinical improvement after FTFV. Radiological improvement was seen in only 9 (75%) of the 12 cases. The follow-up period ranged from 2 to 9.5 years (mean 6.11 ± 2.3 years) after FTFV. Conclusions Fenestration of a TFV via craniotomy is a safe and effective option with a very good long-term outcome and low rate of morbidity.


2017 ◽  
Vol 20 (6) ◽  
pp. 526-541 ◽  
Author(s):  
Brian J. Dlouhy ◽  
Jeffrey D. Dawson ◽  
Arnold H. Menezes

OBJECTIVEThe pathophysiology underlying tonsillar herniation and CSF obstruction in Chiari malformation Type I (CM-I) is unclear, and the cause of CM-I–associated syringomyelia is not well understood. A better understanding of this pathophysiology is important for an improved treatment strategy. Therefore, the authors sought to identify, characterize, and examine the intradural pathology and CSF flow pathophysiology in the posterior fossa and at the level of the foramen magnum that occurs in the setting of CM-I. They determined the incidence of these intradural findings and assessed differences across age, with the degree of tonsillar herniation, and in the presence and absence of syringomyelia.METHODSA prospective database initiated in March 2003 recorded all intraoperative findings during surgical treatment of children and adults with CM-I with or without syringomyelia. A total of 389 surgeries for CM-I were performed in 379 patients between March 2003 and June 2016. A total of 109 surgeries were performed in 109 patients with CM-I (without osseoligamentous abnormalities) in whom both a posterior fossa extradural and intradural decompression with duraplasty was performed (first-time intradural procedures). Using a surgical microscope, intradural pathology and obstruction of CSF channels were identified and assessed. Student t-tests and Fisher’s exact tests compared groups in a series of univariate analyses, followed by multivariate logistic regression.RESULTSThe following intradural pathological entities were observed (prevalence noted in parentheses). These include those that did not obstruct CSF flow channels: opacified arachnoid (33.0%), thickened arachnoid (3.7%), ischemic and gliotic tonsils (40.4%), tonsillar cysts (0.9%), and inferior descent of the fourth ventricle and cervicomedullary junction (CMJ) (78.0%). The following intradural pathological entities were observed to obstruct CSF flow channels: medialized tonsils (100%), tonsil overlying and obstructing the foramen of Magendie (21.1%), intertonsillar and tonsil to CMJ arachnoid adhesions (85.3%), vermian posterior inferior cerebellar artery branches obstructing the foramen of Magendie (43.1%), and arachnoid veils or webs obstructing or occluding the foramen of Magendie (52.3%). Arachnoid veils varied in type and were observed in 59.5% of patients with CM-I who had syringomyelia, which was significantly greater than the 33.3% of patients with CM-I without syringomyelia who had an arachnoid veil (p = 0.018). The presence of CM-I with an arachnoid veil had 3.22 times the odds (p = 0.013, 95% CI 1.29–8.07, by multivariate logistic regression) of being associated with syringomyelia, adjusting for tonsillar herniation. The inferior descent of the fourth ventricle and CMJ occurred with a greater degree of tonsillar herniation (p < 0.001) and correlated with a cervicomedullary kink or buckle on preoperative MRI.CONCLUSIONSIntradural pathology associated with CM-I with or without syringomyelia exists in many forms, is more prevalent than previously recognized in patients of all ages, and may play a role in the pathophysiology of CM-I tonsillar herniation. Arachnoid veils appear to partially obstruct CSF flow, are significantly more prevalent in cases of CM-I with syringomyelia, and therefore may play a role in the pathophysiology of CM-I–associated syringomyelia.


2006 ◽  
Vol 326-328 ◽  
pp. 237-240 ◽  
Author(s):  
Yasushi Sasaki ◽  
Manabu Iguchi ◽  
Mitsutaka Hino

Based on the relationship between quantified blurring degree of Kikuchi bands obtained by an electron backscattering diffraction (EBSD) technique and macroscopic strains measured by a strain gauge, the local compression strain SEBSD in sinter ore has been evaluated under various conditions. There is a good linear relationship between the SEBSD and the strains measured by a strain gauge. The local strain SEBSD evaluated by EBSD patterns can be used as an index of local strains.


1982 ◽  
Vol 62 (1) ◽  
pp. 183-188 ◽  
Author(s):  
R. RIOUX

Barley (Hordeum vulgare L. ’Champlain’) was grown with quackgrass (Agropyron repens (L.) Beauv.) at various densities for 3 yr. According to the regression analysis, a linear relation is appropriate to describe the relationship between yield of barley and biomass or density of quackgrass. A greater proportion of yield variability was explained by density (64%) than by biomass (40%). Density is then a better criterion than biomass to predict yield lost in barley. The linear relationship between barley yield and the shoot density of quackgrass is estimated by the following equation: yield barley = 345.3–0.5682 dens, quackgrass. An increase of 10 shoots/m2 in the mean density of quackgrass resulted in a mean loss of 6 g/m2 in the yield of barley.


2018 ◽  
Vol 17 (2) ◽  
pp. 143-148 ◽  
Author(s):  
Alberto Feletti ◽  
Riccardo Stanzani ◽  
Matteo Alicandri-Ciufelli ◽  
Giuliano Giliberto ◽  
Matteo Martinoni ◽  
...  

AbstractBACKGROUNDDuring surgery in the posterior fossa in the prone position, blood can sometimes fill the surgical field, due both to the less efficient venous drainage compared to the sitting position and the horizontally positioned surgical field itself. In some cases, blood clots can wedge into the cerebral aqueduct and the third ventricle, and potentially cause acute hydrocephalus during the postoperative course.OBJECTIVETo illustrate a technique that can be used in these cases: the use of a flexible scope introduced through the opened roof of the fourth ventricle with a freehand technique allows the navigation of the fourth ventricle, the cerebral aqueduct, and the third ventricle in order to explore the cerebrospinal fluid pathways and eventually aspirate blood clots and surgical debris.METHODSWe report on one patient affected by an ependymoma of the fourth ventricle, for whom we used a flexible neuroendoscope to explore and clear blood clots from the cerebral aqueduct and the third ventricle after the resection of the tumor in the prone position. Blood is aspirated with a syringe using the working channel of the scope as a sucker.RESULTSA large blood clot that was lying on the roof of the third ventricle was aspirated, setting the ventricle completely free. Other clots were aspirated from the right foramen of Monro and from the optic recess.CONCLUSIONWe describe this novel technique, which represents a safe and efficient way to clear the surgical field at the end of posterior fossa surgery in the prone position. The unusual endoscopic visual perspective and instrument maneuvers are easily handled with proper neuroendoscopic training.


Sign in / Sign up

Export Citation Format

Share Document