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Purpose: To clarify the detectability of the choroid plexus of the third ventricle (ChPl3V) with magnetic resonance ventriculography (MRVn) employing a steady-state free precession (SSFP) sequence in comparison to surgical endoscopic movies as a golden standard, as we encountered some clinical cases of total agenesis of corpus callosum (ACC) where we could not recognize the choroid plexus of the third ventricle and found no previous article addressing this problem., Materials and Methods: This retrospective study included consecutive patients from 2010 to 2016 for whom endoscopic evaluation of the third ventricle was conducted. The anterior portion of the right and left streaks of ChPl3V was evaluated in 8 patients on 16 sites, while the posterior portion of both streaks of ChPl3V was evaluated in 13 patients on 26 sites. Sensitivity of MRVn to visualize ChPl3V with endoscopic movies as the golden standard was calculated., Results: Sensitivity of MRVn in visualizing the anterior portion of ChPl3V was 0.813, and that for the posterior portion 0.692. The anterior portion of ChPl3V was visualized in all cases where no tumor contacted the foramen of Monro., Conclusion: MRVn visualizes the anterior portion of ChPl3V with significant sensitivity and the posterior portion with lower one.

Background: There is no facile quantitative method for monitoring hydrocephalus (HCP). We propose quantitative computed tomography (CT) ventriculography (qCTV) as a novel computer vision tool for empirically assessing HCP in patients with subarachnoid hemorrhage (SAH)., Methods: Twenty patients with SAH who were evaluated for ventriculoperitoneal shunt (VPS) placement were selected for inclusion. Ten patients with normal head computed tomography (CTH) findings were analyzed as negative controls. CTH scans were segmented both manually and automatically (by qCTV) to generate measures of ventricular volume., Results: The median manually calculated ventricular volume was 36.1 cm 3 (interquartile range [IQR], 30-115 cm 3 ), which was similar to the median qCTV measured volume of 37.5 cm 3 (IQR, 32-118 cm 3 ) (P = 0.796). Patients undergoing VPS placement demonstrated an increase in median ventricular volume on qCTV from 21 cm 3 to 40 cm 3 on day T-2 and to 51 cm 3 by day 0, a change of 144%. This is in contrast to patients who did not require shunting, in whom median ventricular volume decreased from 16 cm 3 to 14 cm 3 on day T-2 and to 13 cm 3 by day 0, with an average overall volume decrease 19% (P = 0.001). The average change in ventricular volume predicted which patients would require VPS placement, successfully identifying 7 of 10 patients (P = 0.004). Using an optimized cutoff of a change in ventricular volume of 2.5 cm 3 identified all patients who went on to require VPS placement (10 of 10; P = 0.011)., Conclusions: qCTV is a reliable means of quantifying ventricular volume and hydrocephalus. This technique offers a new tool for monitoring neurosurgical patients for hydrocephalus, and may be beneficial for use in future research studies, as well as in the routine care of patients with hydrocephalus., (Copyright © 2017 Elsevier Inc. All rights reserved.)

OBJECTIVE Fetal ventriculomegaly (FV), or enlarged cerebral ventricles in utero, is defined in fetal studies as an atrial diameter (AD) greater than 10 mm. In postnatal studies, the frontooccipital horn ratio (FOHR) is commonly used as a proxy for ventricle size (VS); however, its role in FV has not been assessed. Using image analysis techniques to quantify VS on fetal MR images, authors of the present study examined correlations between linear measures (AD and FOHR) and VS in patients with FV. METHODS The authors performed a cross-sectional study using fetal MR images to measure AD in the axial plane at the level of the atria of the lateral ventricles and to calculate FOHR as the average of the frontal and occipital horn diameters divided by the biparietal distance. Computer software was used to separately segment and measure the area of the ventricle and the ventricle plus the subarachnoid space in 2 dimensions. Segmentation was performed on axial slices 3 above and 3 below the slice used to measure AD, and measurements for each slice were combined to yield a volume, or 3D VS. The VS was expressed as the absolute number of voxels (non-normalized) and as the number of voxels divided by intracranial size (normalized). A Pearson correlation coefficient was used to measure the strength of the relationships between the linear measures and the size of segmented regions in 2 and 3 dimensions and over various gestational ages (GAs). Differences between correlations were compared using Steiger's z-test. RESULTS Fifty FV patients who had undergone fetal MRI between 2008 and 2014 were included in the study. The mean GA was 26.3 ± 5.4 weeks. The mean AD was 18.1 ± 8.3 mm, and the mean FOHR was 0.49 ± 0.11. When using absolute VS, the correlation between AD and 3D VS (r = 0.844, p < 0.0001) was significantly higher than that between FOHR and 3D VS (r = 0.668, p < 0.0001; p = 0.0004, Steiger's z-test). However, when VS was normalized, correlations were not significantly different between AD and 3D VS (r = 0.830, p < 0.0001) or FOHR and 3D VS (r = 0.842, p < 0.0001; p = 0.8, Steiger's z-test). For GAs of 24 weeks or earlier, AD correlated more strongly with normalized 3D VS (r = 0.902, p < 0.0001) than with FOHR (r = 0.674, p < 0.0001; p < 0.0001, Steiger's z-test). After 24 weeks, there was no difference in correlations between linear measures (AD or FOHR) and 3D VS (r > 0.9). Correlations of linear measures with VS in 2 and 3 dimensions were similar, and inclusion of the subarachnoid space did not significantly alter results. CONCLUSIONS Findings in the study support the use of AD as a measure of VS in fetal studies as it correlates highly with both absolute and relative VS, especially at early GAs, and captures the preferential dilation of the occipital horns in patients with FV. Compared with AD, FOHR similarly correlates with normalized VS and, after a GA of 24 weeks, can be reported in fetal studies to provide continuity with postnatal monitoring.

Background: Intraparenchymal cysts without communication to the ventricles or the subarachnoid space are named ependymal or epithelial cysts. The estimated ratio of their incidence compared with arachnoid cysts is 1:10. Neurologic deficit can occur when the cyst exerts mass effect on its surroundings. We evaluated the success rate of endoscopic fenestration of intracranial ependymal cysts., Methods: Our prospectively maintained endoscopy database was screened for all cases of ependymal cysts. The charts were retrospectively reviewed for symptoms, surgery, postoperative course, and complications. Magnetic resonance imaging scans performed before and after surgery were analyzed., Results: We identified 6 patients harboring an intracranial ependymal cyst. The cyst location was frontoparietal, parietal, occipital, or mesencephalic. Patients presented with several symptoms according to the location of the cyst (i.e., epilepsy, hemiparesis, diplopia, hemianopsia). All patients were treated by navigation-guided endoscopic fenestration of the cyst to the ventricular system. Two complications occurred: a cerebrospinal fluid leak, which was managed surgically by wound revision without the need for cerebrospinal fluid shunting, and a chronic subdural hematoma, which occurred 6 weeks after surgery and required burr hole evacuation. Follow-up period ranged from 6 months to 9 years. Magnetic resonance imaging revealed that all cysts decreased in size. Symptoms improved in all patients., Conclusions: Endoscopic fenestration of ependymal cysts to an adjacent ventricular cavity is a treatment option with excellent long-term results and minimal morbidity. It should be considered as the therapy of choice to avoid craniotomy and shunt dependence., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Purpose: To estimate feasible dose reduction to reliably measure ventricular width in adults with hydrocephalus in follow-up cranial computed tomography (CCT) using a custom-made phantom., Materials and Methods: A gelatine-filled adult calvarium with embedded central fibers of two carrots representing the lateral ventricles was used as a phantom. The phantom was scanned 11 times with two CT scanners (LightSpeed Ultra, GE and Somatom Sensation, Siemens), using tube currents of 380/400, 350, 300, 250, 200, 150 and 100 mA, and tube voltages of 140, 120, 100 and 80 kV. The width of the carrots was measured at four sites in consensus decision of two principle investigators blinded to the scan parameters. Values measured at 380/400 mA and 140 kV served as a reference for the width of the ventricles. Measurements received 1 point if they did not differ more than 0.5 mm from the reference values. A maximum score of 4 could be achieved., Results: The relationship between the correct width measurement of the carrots (lateral ventricles) and the radiation dose can be described by a quadratic regression function. Pixel noise increases and accuracy of measurements decreases with a lower radiation dose. Starting from a tube current of 380/400 mA and a tube voltage of 140 kV, the dose can be reduced by 76 % for LightSpeed Ultra and by 80 % for Somatom Sensation provided that a margin of error of 37.5 % (score = 2.5) for correct width measurement of the carrots is accepted., Conclusion: Lowering the radiation dose by up to 48 % for LightSpeed Ultra and by 52 % for Somatom Sensation, compared to the standard protocol (120 kV and 400 mA) still allowed reliable measurements of ventricular widths in this model., Key Points: • There is a quadratic relationship between correct width measurements of lateral ventricles and radiation dose in CT. • Reduction of radiation dose results in increased pixel noise and increased error for correct ventricle width measurement. • Due to a considerable attenuation difference between cerebrospinal fluid and brain parenchyma, a dose reduction for the determination of ventricular size in CT seems feasible and should be performed., (© Georg Thieme Verlag KG Stuttgart · New York.)

During the 1950s through the 1970s, Hans Orthner and Fritz Roeder, two German neurologists from Göttingen, developed a sophisticated technique to perform functional stereotactic surgery with outstanding accuracy. They introduced direct air ventriculography performed in the same surgical session as the ablative stereotactic procedure. For individualized surgical targeting, Orthner prepared a stereotactic atlas (>60 brains) with an ingenious brain-slicing device, the Göttinger macrotome. Brains were grouped based on similarity of six different head and ventricle measurements. A brain cluster representing the best match for a patient was selected for stereotactic targeting. Stereotactic lesions were tailored in an individual manner and shaped by stringing together multiple small coagulations following intraoperative test stimulation. This was achieved from a single probe trajectory by using well-engineered string electrodes with calibrated curving and involved laborious calculations. Only high-frequency thermocoagulation was regarded as appropriate for lesioning. With this meticulous technique, the most advanced stereotactic procedures were performed, including bilateral pallidotomy that ultimately could be restricted to the ansa lenticularis and ventromedial hypothalamotomy, the most delicate stereotactic operation performed to date. Outside Göttingen, this technique has only been used by Prof. Dieter Müller in Hamburg, Germany. This elaborate stereotactic approach is widely unknown and deserves to be discussed in a historical context., (© 2016 S. Karger AG, Basel.)

Introduction: The Apollo system (Penumbra Inc, Alameda, California, USA) is a low profile irrigation-aspiration system designed for the evacuation of intracranial hemorrhage., Objective: To demonstrate the feasibility of using Apollo in combination with cone beam CT guidance., Methods: Parenchymal (n=1) and mixed parenchymal-intraventricular hematomas (n=1) were created in cadaver heads using a transvascular (n=1) or transcranial (n=1) approach. Hematomas were then imaged with cone beam CT (CB-CT), and the long axis of the hematoma defined. The CB-CT data were then used to guide transcranial access to the hematoma-defining the location of the burr hole and the path to the leading edge of the hematoma. An 8F vascular sheath was then placed under live fluoroscopic guidance into the hematoma. A second CB-CT was performed to confirm localization of the sheath. The hematoma was then demarcated on the CB-CT and the Apollo wand was introduced through the 8F sheath and irrigation-aspiration was performed under (periodic) live fluoroscopic guidance. The operators manipulated the wand within the visible boundaries of the hematoma. After irrigation-aspiration, a control CB-CT was performed to document reduction in hematoma volume., Results: Transvascular and transcranial techniques were both successful in creating intracranial hematomas. Hematomas could be defined with conspicuity sufficient for localization and volumetric measurement using CB-CT. Live fluoroscopic guidance was effective in navigating a sheath into the leading aspect of a parenchymal hematoma and guiding irrigation-aspiration with the Apollo system. Irrigation-aspiration reduced the parenchymal hemorrhage volume from 14.8 to 1.7 cc in 189 s in the first case (parenchymal hemorrhage) and from 26.4 to 4.1 cc in 300 s in the second case (parenchymal and intraventricular hemorrhage)., Conclusions: The cadaver model described is a useful means of studying interventional techniques for intracranial hemorrhage. It seems feasible to use CB-CT to guide the evacuation of intraparenchymal and intraventricular hemorrhage using the Apollo system through a minimally invasive transcranial access., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Neuroendoscopic endonasal approach has gained popularity in managing traumatic, spontaneous, and especially iatrogenic cerebrospinal fluid (CSF) rhinorrhea. The authors examined 8 patients presenting with CSF rhinorrhea between December 2012 and June 2014: 5 patients had iatrogenic leak, 2 patients had traumatic leak, and 1 patient had a spontaneous onset of CSF rhinorrhea. Sites of the CSF leaks were detected through computed tomographic cisternography and magnetic resonance imaging in the patients with traumatic and spontaneous leaks. All patients received neuroendoscopic endonasal surgery for the CSF leak. The largest defect was 22 mm in maximum diameter. Endoscopic supraciliary "keyhole" approach was performed in 1 patient after confirmation of a frontal sinus leak using the endoscopic endonasal approach. The success rate was 100% in the first attempt. Follow-up period ranged from 3 to 24 months, and no recurrence was reported. Identifying the leak site and choosing the appropriate surgical technique remain the most important factor in surgical success.

Purpose: to study effect of coronary artery bypass graft (CABG) surgery with cardiopulmonary bypass (CPB) on regional cerebral blood flow and cognitive function in patients with ischemic heart disease (IHD)., Material and Methods: We included into this study 22 patients with IHD subjected to CABG surgery with CPB. All patients underwent brain SPECT scanning and comprehensive neuropsychological testing 1 day before, 10-14 days and 6 months after surgery., Results: Overall CABG with CPB was followed by reduction of regional cerebral blood flow relative to baseline in frontal and parietal cortex (p < 0.01). Substantial reduction (> 5%) of cerebral perfusion in early postoperative period was observed in 15 patients (68%) while seven patients (32%) had no significant changes of regional cerebral blood flow. Changes of cerebral perfusion correlated with dynamics of cognitive status. Mean measures of immediate verbal memory, delayed memory, and learning decreased after surgery by 25.6 (p = 0.002), 43.3 (p = 0.000003), and 23.1% (p = 0.00000), respectively. Moreover after CABG with CPB patients demonstrated slowing of psychomotor speed by 13.6% (p = 0.03)., Conclusion: CABG with CPB was associated with reduction of cerebral perfusion leading to cognitive dysfunction. Immediate and delayed verbal and visual memory, learning and psychomotor speed were most sensitive to the negative effects of surgery.

Background and Purpose: CT is a ubiquitous, efficient, and cost-effective method to evaluate pediatric ventricular size, particularly in patients with CSF shunt diversion who often need emergent imaging. We therefore sought to determine the minimum dose output or CT dose index required to produce clinically acceptable examinations., Materials and Methods: Using a validated noise insertion method and CT projection data from 22 patients, standard pediatric head CT images were reconstructed with weighted filtered back-projection and sinogram-affirmed iterative reconstruction corresponding to routine, 25%, and 10% dose. Reconstructed images were then evaluated by 3 neuroradiologists (blinded to dose and reconstruction method) for ventricular size, diagnostic confidence, image quality, evidence of hemorrhage, and shunt tip location, and compared with the reference standard., Results: There was no significant difference in the ventricular size ranking, and the sensitivity for moderate to severe hydrocephalus was 100%. There was no significant difference between the full-dose level and the ventricular size rankings at the 25% or the 10% dose level for either reconstruction kernel (P > .979). Diagnostic confidence was maintained across doses and kernel. Hemorrhage was more difficult to identify as image quality degraded as dose decreased but was still seen in a majority of cases. Shunts were identified by all readers across all doses and reconstruction methods., Conclusions: CT images having dose reductions of 90% relative to routine head CT examinations provide acceptable image quality to address the specific clinical task of evaluating ventricular size., (© 2014 by American Journal of Neuroradiology.)

Characterization of hematomas is essential in scan reading, manual delineation, and designing automatic segmentation algorithms. Our purpose is to characterize the distribution of intraventricular (IVH) and intracerebral hematomas (ICH) in NCCT scans, study their relationship to gray matter (GM), and to introduce a new tool for quantitative hematoma delineation. We used 289 serial retrospective scans of 51 patients. Hematomas were manually delineated in a two-stage process. Hematoma contours generated in the first stage were quantified and enhanced in the second stage. Delineation was based on new quantitative rules and hematoma profiling, and assisted by a dedicated tool superimposing quantitative information on scans with 3D hematoma display. The tool provides: density maps (40-85HU), contrast maps (8/15HU), mean horizontal/vertical contrasts for hematoma contours, and hematoma contours below a specified mean contrast (8HU). White matter (WM) and GM were segmented automatically. IVH/ICH on serial NCCT is characterized by 59.0HU mean, 60.0HU median, 11.6HU standard deviation, 23.9HU mean contrast, -0.99HU/day slope, and -0.24 skewness (changing over time from negative to positive). Its 0.1(st)-99.9(th) percentile range corresponds to 25-88HU range. WM and GM are highly correlated (R (2)=0.88; p<10(-10)) whereas the GM-GS correlation is weak (R (2)=0.14; p<10(-10)). The intersection point of mean GM-hematoma density distributions is at 55.6±5.8HU with the corresponding GM/hematoma percentiles of 88(th)/40(th). Objective characterization of IVH/ICH and stating the rules quantitatively will aid raters to delineate hematomas more robustly and facilitate designing algorithms for automatic hematoma segmentation. Our two-stage process is general and potentially applicable to delineate other pathologies on various modalities more robustly and quantitatively.

Third ventricle tumors are uncommon central nervous system lesions and unusual locations for metastatic colorectal cancer. We present a case of a 68 year old woman with a solitary 3rd ventricle lesion found on a computed tomography scan of the brain and the synchronous mass of the right colon. The aim in this case was local control of cerebral lesion with pathological diagnosis. Surgery was followed by a short-term good evolution but with sudden death.

Background: Endoscopic third ventriculostomy (ETV) is the preferred method for the treatment of noncommunicating hydrocephalus. The different success rates of ETV indicate the difficulties in predicting the success of this procedure., Objective: To show the usefulness of intraoperative ventriculography performed by the low-field 0.15-T magnetic resonance imager Polestar N20 during ETV., Methods: The study was conducted in 11 patients with noncommunicating hydrocephalus caused by tumors or cysts of the third ventricle (n = 5), nontumoral stenosis of the sylvian aqueduct (n = 3), and fourth ventricle outlet obstruction (n = 3). Intraoperative magnetic resonance (iMR) ventriculography was performed before and after the ETV., Results: In each case, iMR-ventriculography was a safe procedure and determined the exact site of obstruction of cerebrospinal fluid flow. In all cases, iMR-ventriculography performed after ETV showed with the greatest accuracy the patency of the performed fenestrations, demonstrating in 9 patients good flow of the contrast from the third ventricle to the basal cisterns, restricted flow in 1 patient, and no flow in 1 patient. The results of ventriculography were consistent with the postoperative neurological status of operated-on patients. In 3 patients, the opinion of the surgeons about the patency of endoscopic fenestration, based on intraoperative observation of the third ventricle floor, was inconsistent with the results from iMR-ventriculography., Conclusion: Low-field iMR-ventriculography is a safe procedure that can be successfully applied during ETV to determine the site of obstruction in hydrocephalus and the patency of performed ventricle fenestration.

Intraventricular and ependymal lesions comprise a wide spectrum of tumoral, cystic, vascular, infectious and inflammatory disorders. With respect to tumoral and cystic diseases, the location, age and CT and MRI patterns are the main factors for diagnosis. The MRI findings of infectious diseases are supported by the clinical history, immune status and laboratory findings. Intracranial associated lesions may be very helpful for the diagnosis of Sturge-Weber, subependymal giant cell astrocytoma and systemic diseases, such as sarcoidosis and histiocytosis. Intraventricular vascular lesions are rare but present typical features on neuroimaging. The aim of this review is to provide a detailed description of these disorders with an emphasis on the key imaging findings and to generate a narrow differential diagnosis. We present a diagnostic approach based on the solid or cystic aspect of the intraventricular focal mass, its origin from the ventricular wall or choroid plexus and its location within the ventricular system. We also propose a differential diagnosis for ependymal dissemination: the ependymal enhancement may be due to ventriculitis from adjacent parenchymal lesions, the ependymal spread of tumors or infectious or inflammatory/systemic diseases., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)

Subarachnoid hemorrhage (SAH) with intraventricular hemorrhage (IVH) is associated with poor outcomes. The aim of this study was to evaluate the safety and feasibility of combined coiling and neuroendoscopy for treating severe SAH with massive IVH. Between April 2008 and June 2011, 49 patients with a severe SAH were treated at the Department of Neurosurgery, Fukuoka University, Japan; 10 of these patients had a massive IVH with a ruptured aneurysm. All 10 patients (three men and seven women; mean age, 63.1±8.5 years) were treated with coiling and neuroendoscopic removal of the IVH within 2 days of onset. Coiling was successfully performed at a mean volume embolization ratio of 21.8±5.5%. Neuroendoscopic removal of the IVH reduced the mean Graeb score from 10.5±2.0 to 4.8±2.5 (p=0.005). All external drains were removed on day 3. No rebleeding or acute hydrocephalus was noted. The Glasgow Outcome Scale scores at discharge indicated two patients with good recovery, three with moderate disability, four in a vegetative state, and one dead. A good modified Rankin Scale (mRS) score (0-2) at least 6 months later (mean follow-up period, 15.4±9.2 months) was observed for five patients (50%), and a poor mRS score (3-6) was observed for the remaining four patients. Neuroendoscopically removing the IVH from all of the ventricles between the lateral and the fourth ventricle and coiling the ruptured aneurysm is a safe, feasible approach for treating severe SAH with massive IVH., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Background: Endoscopic third ventriculostomy (ETV) has become a well-established method for the treatment of noncommunicating hydrocephalus with a high success rate and a relatively low morbidity rate. However, vessel injury has been repeatedly reported, often with a fatal outcome. Vessel injury is considered to be the most threatening complication. The use of indocyanine green (ICG) angiography has become an established tool in vascular microneurosurgery., Objective: We report our initial experience with endoscopic ICG angiography in ETV for intraoperative visualization of the basilar artery and its perforators to reduce the risk of vascular injury., Methods: Eleven patients with noncommunicating hydrocephalus underwent ETV. Before opening of the third ventricular floor, ICG angiography was performed using a prototype neuroendoscope for intraoperative visualization of ICG fluorescence., Results: In 10 patients, ETV and ICG angiography were successfully performed. In 1 case, ICG angiography failed. Even in the presence of an opaque floor of the third ventricle (n = 5), ICG angiography clearly demonstrated the course of the basilar artery and its major branches and was considered useful., Conclusion: ICG angiography has the potential to become a useful adjunct in ETV for better visualization of vessel structures, especially in the presence of aberrant vasculature, a nontranslucent floor of the third ventricle, or in case of reoperations.

The Cavum Septi Pellucidi (CSP), Cavum Vergae (CV) and Cavum Veli Interpositi, are anatomical variants located in the midline of the brain. It is important to identify these conditions to distinguish them from other entities that may require treatment. In this paper, our purpose is to describe MR and CT findings of CSP, CV and Cavum Veli Interpositi, explaining the differential diagnosis., (Copyright © 2013 by the American Society of Neuroimaging.)

Background: The prevalent method of ventriculostomy placement is via freehand insertion to cannulate the ventricle at a 90° angle to the skull to get ideal placement. Our goal was to test the validity of this practice in patients without midline shift and with normal ventricular size., Methods: This study was a virtual radiographic analysis of 3-dimensional data of skull and ventricular anatomy. Data were collected using thin-cut (1-mm) computed tomography scans of 101 randomly selected patients with normal ventricular anatomy. Virtual ventriculostomy trajectories were determined for entry from the right and left sides separately, going in at a 90° angle to the skull. Three-dimensional multiplanar reconstructions were performed using Osirix software to see where the catheter would end up within the brain., Results: In our patient population, the mean bicaudate index was 0.14. Of the 202 perpendicular lines created from Kocher's point into the brain, 67.8% (137) of the virtual lines passed through the ipsilateral frontal horn of the lateral ventricle, 20.8% (42) passed through the contralateral ventricle, and 10.4% (21) did not pass through a ventricular space. A lower bicaudate index also leads to a greater misplacement even with a perpendicular trajectory. Pushing a catheter beyond an entry length of 6.5 cm if no cerebrospinal fluid flow has been obtained will not result in ipsilateral ventricular catheterization., Conclusions: Our study concludes that not all catheters passed through Kocher's point using a perpendicular trajectory will end up in the ipsilateral frontal horn, and almost 10% of these catheters will be in a nonventricular space. In the instance in which a freehand pass fails to cannulate a ventricle, the safest alternative would be to make only minor adjustments to the perpendicular angle., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Object: In this paper the authors' goal was to investigate the clinical usefulness of Gd-enhanced MR ventriculography (MRV) in pediatric patients affected by multiloculated hydrocephalus., Methods: Eighteen patients (11 boys and 7 girls, age range 2-14 months) with a diagnosis of multiloculated hydrocephalus were included in the study. After injection of gadodiamide (0.02-0.04 mmol) into the lateral ventricle by tapping the anterior fontanel, sagittal, coronal, and axial T1-weighted MR images were acquired. The location of the septations and the sites of obstruction of CSF flow were assessed. Postoperative MRV was obtained to confirm the results of endoscopic treatment in most complex cases., Results: No adverse events were observed after injection of contrast medium into the ventricular system. Preoperative MRV accurately defined the exact morphology of septae and ventricular walls in all cases. In 1 case the diagnosis of multiloculated hydrocephalus was ruled out. Sites of obstruction of CSF flow within the ventricular system were also well established. In 4 cases the multiple compartments were proven to intercommunicate. Postoperative MRV was useful in assessing the functional status of third ventriculostomy, aqueductoplasty, and other endoscopic fenestrations., Conclusions: Magnetic resonance ventriculography is a safe, effective, and reliable technique. The accurate definition of the anatomy of the ventricles and the site of obstruction in multiloculated hydrocephalus can help to plan the most appropriate treatment and minimize the number of procedures. Although MRV is also useful during postoperative follow-up to determine the results of endoscopic treatment, it should be limited to particularly complex cases, due to its invasiveness.

Objectives: To determine whether the extent of white matter lesions on a CT scan of acute intracerebral hemorrhage patients is associated with the prevalence and severity of intraventricular extension of hemorrhage., Design and Setting: A post hoc analysis of Acute Brain Bleeding Analysis-IntraCerebral Hemorrhage cohort, a nationwide prospective cohort of acute intracerebral hemorrhage patients (total number of cohort subjects, 1,604)., Patients: Spontaneous intracerebral hemorrhage patients (n = 1,262)., Interventions: None., Measurements: The authors analyzed CT scan images taken within 48 hours after stroke onset. Extent of white matter lesions, volume of intracerebral hemorrhage, presence of intraventricular extension of hemorrhage, and intraventricular extension of hemorrhage score (approximation of intraventricular extension of hemorrhage volume) were measured using CT scans, and demographic, laboratory, clinical, and mortality data were also gathered through review of medical records and retrieval from the governmental statistical archive., Main Results: The frequency of intraventricular extension of hemorrhage in our population was 27.2% (343 subjects). The proportion of extensive white matter lesions in intraventricular extension of hemorrhage subjects (33.8%) was higher than that of non-intraventricular extension of hemorrhage cases (16.3%; p < 0.01). Multivariable analysis showed that mild (odds ratio, 1.48; 95% confidence interval 1.05- 0.09; p < 0.01) and extensive (odds ratio, 2.73; 95% confidence interval 1.88-3.98; p < 0.01) white matter lesions were significantly associated with the presence of intraventricular extension of hemorrhage in spontaneous intracerebral hemorrhage patients. The estimated mean of the intraventricular extension of hemorrhage score from the extensive white matter lesions group (9.09 ± 0.76) was significantly higher than that of the no white matter lesions group (6.72 ± 0.78; p < 0.01 from analyses of covariances) after adjustment for relevant covariates., Conclusions: We documented that the severity of white matter lesions is related to the occurrence and amount of intraventricular extension of hemorrhage in spontaneous intracerebral hemorrhage cases.

Background: During external ventricular drainage (EVD) weaning, cranial computed tomography (cCT) is necessary to evaluate ventricle width. Because intrahospital transfer of critically ill patients is associated with higher mortality, bedside techniques are necessary to evaluate ventricle width. Transcranial sonography is able to show the ventricles in patients with sufficient temporal acoustic window. Contrast-enhanced ultrasound (CEUS) is able to overcome the limitations of insufficient insonation., Objective: We demonstrate the feasibility of bedside transcranial CEUS ventriculography to measure ventricles and verify the passage of cerebrospinal fluid (CSF) through the foramen of Magendie into the subarachnoid space during EVD weaning in critically ill patients., Methods: Six patients were examined by transcranial and transnuchal CEUS. Harmonic imaging with low mechanical index was used. One milliliter of an ultrasound contrast agent was administered via EVD line. Comparison with the cCT scans at the time of discharge was used to confirm CEUS-ventriculography results., Results: Ventricles were visualized in all patients. CSF transmission via the foramen of Magendie was demonstrated in 5 patients. Mean ventricle width (centimeters) was 0.67 (CEUS) vs 0.73 (cCT) (standard deviation 0.43, 0.45, P = .116) [third ventricle], 0.88 vs 1.02 (0.28, 0.22, P = .055) [fourth ventricle], 1.40 vs 1.37 (0.56, 0.54, P = .620) [left lateral ventricle], 1.37 vs 1.37 (0.55, 0.54, P = .952) [right lateral ventricle], 2.33 vs 2.23 (0.51, 0.58, P = .169) [left anterior horn], and 2.25 vs 2.07 (0.56, 0.64, P = .204) [right anterior horn]. Mean duration for CEUS ventriculography was 3:15 minutes., Conclusion: CEUS ventriculography is an effective bedside procedure in critically ill patients with EVD. CEUS allows measurement of ventricle width, ventricle communication, and CSF transfer to the subarachnoidal space through the cisternal foramina.

Background and Aim: The role of imaging for the detection of vascular lesions in patients with intracerebral hemorrhage (ICH) is poorly defined. A study was undertaken to compare the yield of digital subtraction angiography (DSA) in patients with ICH with intraventricular hemorrhage (IVH) and those without IVH., Methods: The DSA database at our institution was reviewed for patients who underwent DSA for acute spontaneous ICH over a period of 68 months. Patients with known vascular malformation or brain neoplasm, prior surgery, ischemic infarction, subarachnoid hemorrhage or isolated IVH were excluded. Patients were grouped into those with associated IVH (group A) and those without (group B). Baseline demographic and clinical data, non-contrast head CT (NCCT) probability for a vascular lesion and angiographic results were compared., Results: 293 patients met the inclusion and exclusion criteria (141 women, 152 men, mean age 57, range 18-88), 139 in group A and 154 in group B. Age and sex distributions were similar (p>0.05). Group A patients were more likely to be hypertensive or coagulopathic (p=0.001). Group B had more patients with high probability NCCT scans (p<0.001). Underlying vascular lesions were found in 21 patients (15.1%) in group A and 34 (22.1%) in group B (p>0.05)., Conclusion: The presence of IVH in patients with acute spontaneous ICH is not associated with an increased risk of an underlying vascular lesion and should not be used to select patients for neurovascular evaluation.

Background and Purpose: The purpose of our study was to compare lesion location between moyamoya disease-related intracerebral hemorrhage (MMD-ICH) and primary intracerebral hemorrhage (P-ICH)., Methods: Ninety-three patients each with MMD-ICH and P-ICH were compared. In patients with MMD-ICH, angiographic findings were assessed with special attention to the prominent anterior choroidal artery. Follow-up data were obtained through clinical visit and telephone interview., Results: The location of hemorrhage was different between MMD-ICH and P-ICH, the most frequent one being intraventricular region (37.6%) in the former and putaminal region (46.2%) in the latter (P<0.001). Intraventricular hemorrhage was more frequent in MMD-ICH than P-ICH (80.6% versus 20.4%, P<0.001). In MMD-ICH, primary intraventricular hemorrhage was more closely associated with prominent ipsilateral anterior choroidal artery than ICHs without intraventricular hemorrhage (75.0% versus 16.7%, P<0.001). Higher rates of rebleeding and infarction were observed in MMD-ICH than in age- and sex-matched patients with P-ICH., Conclusions: MMD-ICH may differ from P-ICH in hemorrhage location, generally presenting with intraventricular hemorrhage with or without ICH, which may be due to a prominent anterior choroidal artery. Patients with MMD may be more likely to experience recurrent bleeding and infarction.

Objectives: To evaluate the possible role of Magnetic Resonance (MR) signal intensity measurements in diagnosing Central Nervous System (CNS) anomalies antenatally., Methods: MR images of 110 fetal brains between 18 and 38 weeks were studied. Nine were excluded due to destroyed brain. 50 had CNS anomalies. 51 had normal CNS and were used as controls. Regions of interest (ROI) cursors were placed in Vitreous, cerebellar vermis, thalamus, frontal white matter, corona radiata, periventricular region and grey matter. The lateral ventricle diameters were also obtained. Signal intensity ratio (SIR) was calculated by the signal intensity of each of the above regions to that of the vitreous. SIR in controls were compared with fetuses having: (1) Hydrocephalus. (2) Arnold Chiari type-2 Malformation (ACM-2) (3) Non-progressive ventriculomegaly (4) Miscellaneous CNS anomalies. The correlation of the normalcy or abnormalcy of the brain was based on Clinical/Physical examination in 51, Ultrasound in 20, MRI in 2 and autopsy in 28., Results: In hydrocephalus and ACM-2, the SIR of vermis and periventricular region were higher than controls whereas in non-progressive ventriculomegaly and miscellaneous CNS anomalies there was no significant difference., Conclusion: Signal intensity measurements are useful to differentiate physiological and non-progressive ventriculomegaly from hydrocephalus and ACM-2.

Aim: To present the neuroradiological and clinical findings of fourth-ventricular meningiomas to increase awareness of this entity., Materials and Methods: The computed tomography (CT; n=5), magnetic resonance imaging (MRI; n=9) features and clinical presentations of 10 patients with pathologically documented fourth-ventricular meningiomas were retrospectively analysed., Results: All tumours appeared as well-demarcated masses in the fourth ventricle at CT and MRI. The tumour shape was round in eight cases (80%) and irregular in two cases (20%). The CT images of five cases showed predominantly isoattenuation in three cases and high attenuation in two cases, with a mean attenuation value of 52 HU. In addition, calcifications were seen in three cases. At MRI, nine masses were isointense (n=6) or hypointense (n=3) to grey matter on T1-weighted images and mildly hyperintense (n=4), isointense (n=3), hypointense (n=1), and of mixed signal intensity (n=1) on T2-weighted and fluid-attenuated inversion recovery (FLAIR) images. Signal voids were visible in two cases. Enhancement after injection of contrast material was marked homogeneous (n=5) or heterogeneous (n=5) on CT or T1-weighted images. Three tumours had mild peritumoural oedema. Three tumours were associated with obstructive hydrocephalus. The pathological subtype of the 10 meningiomas was fibromatous (n=5), atypical (n=2), and one each of transitional, psammomatous, and clear-cell type., Conclusion: Although fourth-ventricular meningioma is quite rare, it should be considered in differential diagnosis of neoplasms within the fourth ventricle. The relatively typical radiological appearance, combined the age and sex of patients, can suggest the diagnosis of fourth-ventricular meningioma., (Copyright © 2011 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

Accurate segmentation of ventricular cerebrospinal fluid (CSF) regions in stroke CT images is important in assessing stroke patients. Manual segmentation is subjective, time consuming and error prone. There are currently no methods dedicated to extracting ventricular CSF regions in stroke CT images. 102 ischemic stroke CT scans (slice thickness between 3 and 6 mm, voxel size in the axial plane between 0.390 and 0.498 mm) were acquired. An automated template-based algorithm is proposed to extract ventricular CSF regions which accounts for the presence of ischemic infarct regions, image noise, and variations in orientation. First, template VT(2) is registered to the scan using landmark-based piecewise linear scaling and then template VT(1) is used to further refine the registration by partial segmentation of the fourth ventricle. A region of interest (ROI) is found using the registered VT(2). Automated thresholding is then applied to the ROI and the artifacts are removed in the final phase. Sensitivity, dice similarity coefficient, volume error, conformity and sensibility of segmentation results were 0.74 ± 0.12, 0.8 ± 0.09, 0.16 ± 0.11, 0.45 ± 0.39, 0.88 ± 0.09, respectively. The processing time for a 512 × 512 × 30 CT scan takes less than 30 s on a 2.49 GHz dual core processor PC with 4 GB RAM. Experiments with clinical stroke CT scans showed that the proposed algorithm can generate acceptable results in the presence of noise, size variations and orientation differences of ventricular systems and in the presence of ischemic infarcts.

Purpose: Fourth ventricular outlet obstruction (FVOO) causes obstructive hydrocephalus. Often, despite high-quality MRI sequences, differentiation between FVOO and communicating (absorptive) hydrocephalus is not easy. We describe our initial experience with five children with suspected FVOO that underwent CT ventriculography (CTV) or cisternography (CTC), to assist with this difficult diagnosis., Methods: Over 2.5 years, five children with suspected FVOO (5 months-7.5 years old) underwent CTV or CTC. Technical and clinical data were retrospectively collected., Results: Four children had progressive macrocephaly, and one child had progressive ventriculomegaly. On CTV/CTC, four of five children showed communication between the ventricular system and spinal subarachnoid space or prepontine cistern, as evidenced by passage of contrast material. One child had a FVOO and therefore underwent an endoscopic third ventriculostomy, and is since, symptom and shunt free for 2.5 years., Conclusion: CT ventriculography in infants, and CT cisternography in elder children, may assist to differentiate between FVOO and communicating hydrocephalus. The importance of these tests is for children with MRI suggestive of FVOO related hydrocephalus, but with no clear demonstration of the obstruction site. The implication of this differentiation may be for deciding between treatment of hydrocephalus with a ventriculoperitoneal shunt or with an endoscopic third ventriculostomy.

Purpose: To investigate the dosimetric advantage of intensity-modulated radiotherapy (IMRT) for whole ventricles (WV) in patients with a localized intracranial germinoma receiving induction chemotherapy., Methods and Materials: Data from 12 consecutive patients with localized intracranial germinomas who received induction chemotherapy and radiotherapy were used. Four-field coplanar three-dimensional conformal radiotherapy (3D-CRT) and seven-field coplanar IMRT plans were created. In both plans, 24 Gy was prescribed in 12 fractions for the planning target volume (PTV) involving WV and tumor bed. In IMRT planning, optimization was conducted to reduce the doses to the organs at risk (OARs) as much as possible, keeping the minimum dose equivalent to that of 3D-CRT. The 3D-CRT and IMRT plans were compared in terms of the dose-volume statistics for target coverage and the OARs., Results: IMRT significantly increased the percentage volume of the PTV receiving 24 Gy compared with 3D-CRT (93.5% vs. 84.8%; p = 0.007), while keeping target homogeneity equivalent to 3D-CRT (p = 0.869). The absolute percentage reduction in the irradiated volume of the normal brain receiving 100%, 75%, 50%, and 25% of 24 Gy ranged from 0.7% to 16.0% in IMRT compared with 3D-CRT (p < 0.001). No significant difference was observed in the volume of the normal brain receiving 10% and 5% of 24 Gy between IMRT and 3D-CRT. Conformation number was significantly improved in IMRT (p < 0.001). For other OARs, the mean dose to the cochlea was reduced significantly in IMRT by 22.3% of 24 Gy compared with 3D-CRT (p < 0.001)., Conclusions: Compared with 3D-CRT, IMRT for WV improved the target coverage and reduced the irradiated volume of the normal brain in patients with intracranial germinomas receiving induction chemotherapy. IMRT for WV with induction chemotherapy could reduce the late side effects from cranial irradiation without compromising control of the tumor., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Neurocysticercosis (NCC), caused by the pork tapeworm Taenia solium, is reported to be a common condition in Nepal. So far imaging diagnosis was mainstay of the diagnosis. In this paper, we report three patients presenting with neurological symptoms due to intraventricular NCC. We have diagnosed the causative agent as T. solium on molecular basis. Further research is warranted to assess the actual health impact of T. solium in Nepal.

Objective: To estimate the prevalence, associated anomalies, progression, and clinical outcome in fetuses diagnosed with mild to moderate ventriculomegaly at 18-24 weeks of pregnancy., Methods: This was a prospective population-based study from the North of England. Data were extracted from the U.K. Northern Congenital Abnormality Survey for cases identified during 1994-2008. Additional anomalies present were categorized according to European Surveillance of Congenital Anomalies guidelines. Differences between isolated and nonisolated ventriculomegaly were examined by either Fisher's exact test or Mann-Whitney U test. Changes in prevalence were examined by the χ² test for trend., Results: There were 355 cases of confirmed mild to moderate ventriculomegaly in singleton pregnancies at 18-24 weeks of gestation among 454,080 registered births, giving a total prevalence of 7.8 per 10,000 registered births (95% confidence interval [CI] 7.0-8.7). The minimum rate of chromosomal anomaly and trisomy 21 (including cases karyotyped postnatally) in isolated cases (ie, in which no other structural anomaly was identified prenatally) was 10.2% (95% CI 6.1-16.0) and 4.5% (95% CI 2.0-8.7), respectively. Additional structural anomalies were identified prenatally in 43.1% of cases. Among isolated cases, 61.9% (95% CI 53.3-70.0) resolved by the final prenatal scan (the majority by 24 weeks of gestation) and 10.7% (95% CI 6.4-16.6) were found to have "missed" structural anomalies after birth. The probability of an infant death for isolated ventriculomegaly was 3% (95% CI 0.8-7.6)., Conclusion: This register-based study on mild to moderate ventriculomegaly provides unique epidemiologic and outcome data. Information from this study should aid in counseling parents., Level of Evidence: III.

Objective: The optimal management of medically refractory idiopathic intracranial hypertension (IIH) remains a point of debate. The senior author's practice evolved after a review of our units' practice in placing lumboperitoneal shunts revealed an unacceptably high rate of complication and revision. We now preferentially perform custom-designed electromagnetic (EM) image-guided ventriculoperitoneal shunt placement instead of lumboperitoneal shunting in treating medically refractory IIH and present our outcome data with this technique., Patients and Methods: Retrospective case note review was carried out with prospective follow-up of 17 patients treated consecutively over a 3-year period., Outcome Measures: The article aims to assess the implication of using EM image-guided tracking technology in ventricular catheter placement in patients with IIH and to assess outcome., Results: All of the patients improved clinically at the last follow-up compared to their preoperative condition. None of the patients experienced intra- or perioperative complications. All patients underwent ventriculoperitoneal shunt placement using EM guidance navigation. All patients in the EM subgroup were cannulated with a single pass, and satisfactory catheter placement was confirmed on a postoperative CT scan with concordant patient symptom improvement., Conclusion: Our series suggests that EM image-guided ventriculoperitoneal cerebrospinal fluid (CSF) shunting for IIH is a safe and effective procedure for ventricular cannulation and placement., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Purpose: To estimate the minimum dose needed at follow-up cranial computed tomography (CCT) to reliably determine ventricular width in children with hydrocephalus., Materials and Methods: For the study, a phantom was created using the calvarium of an infant which was filled with gelatin and the shaped inner cones of two carrots serving as lateral ventricles. The phantom was scanned ten times with two multi-slice CTs (LightSpeed Ultra, GE, and Somatom Sensation, Siemens), using a tube current of 400, 350, 300, 250, 200, 150, and 100 mA, and a tube voltage of 140, 120, 100, and 80 kV. The width of both lateral ventricles was measured at 4 sites. The values derived from scans performed at 380/400 mA and 140 kV (LightSpeed/Somatom) served as a reference. Measurements scored 1 point if they did not differ by more than 0.5 mm from the reference values., Results: The radiation dose can be reduced from 61.0 mGy to 9.2 mGy (15.1%) with LightSpeed and from 55.0 mGy to 8.0 mGy (14.6%) with Somatom without impairing the reliability of ventricular width measurements. However, in the case of both scanners, certain combinations of tube voltage and current yielded less reliable measurements although the dose was higher and the pixel noise was lower., Conclusion: There is no single cut-off dose or setting for tube voltage and current which guarantees reliable ventricular width measurements with the least radiation exposure for both scanners. As a guideline, it is safe to use the standard protocols with a reduced tube current of 100 kV., (© Georg Thieme Verlag KG Stuttgart · New York.)

Rationale and Objectives: Accurate segmentation of the brain ventricular system on computed tomographic (CT) imaging is useful in neurodiagnosis and neurosurgery. Manual segmentation is time consuming, usually not reproducible, and subjective. Because of image noise, low contrast between soft tissues, large interslice distance, large shape, and size variations of the ventricular system, no automatic method is presently available. The authors propose a model-guided method for the automated segmentation of the ventricular system., Materials and Methods: Fifty CT scans of patients with strokes at different sites were collected for this study. Given a brain CT image, its ventricular system was segmented in five steps: (1) a predefined volumetric model was registered (or deformed) onto the image; (2) according to the deformed model, eight regions of interest were automatically specified; (3) the intensity threshold of cerebrospinal fluid was calculated in a region of interest and used to segment all regions of cerebrospinal fluid from the entire brain volume; (4) each ventricle was segmented in its specified region of interest; and (5) intraventricular calcification regions were identified to refine the ventricular segmentation., Results: Compared to ground truths provided by experts, the segmentation results of this method achieved an average overlap ratio of 85% for the entire ventricular system. On a desktop personal computer with a dual-core central processing unit running at 2.13 GHz, about 10 seconds were required to analyze each data set., Conclusion: Experiments with clinical CT images showed that the proposed method can generate acceptable results in the presence of image noise, large shape, and size variations of the ventricular system, and therefore it is potentially useful for the quantitative interpretation of CT images in neurodiagnosis and neurosurgery., (Copyright (c) 2010 AUR. Published by Elsevier Inc. All rights reserved.)

We report a case of fourth ventricular mixed germ cell tumor (GCT) in a 20-year-old man. Neuroradiological investigations revealed a fourth ventricular hemorrhagic tumor with adipose tissue. We suspected mixed GCT because adipose tissue was seen preoperatively, but mixed GCT occurring after childhood in this location has not previously been reported. We describe herein the imaging findings for mixed GCT and discuss the differential diagnoses of fourth ventricular tumors with adipose tissue.

Background: Accurate analysis of CT brain scans is vital for diagnosis and treatment of Traumatic Brain Injuries (TBI). Automatic processing of these CT brain scans could speed up the decision making process, lower the cost of healthcare, and reduce the chance of human error. In this paper, we focus on automatic processing of CT brain images to segment and identify the ventricular systems. The segmentation of ventricles provides quantitative measures on the changes of ventricles in the brain that form vital diagnosis information., Methods: First all CT slices are aligned by detecting the ideal midlines in all images. The initial estimation of the ideal midline of the brain is found based on skull symmetry and then the initial estimate is further refined using detected anatomical features. Then a two-step method is used for ventricle segmentation. First a low-level segmentation on each pixel is applied on the CT images. For this step, both Iterated Conditional Mode (ICM) and Maximum A Posteriori Spatial Probability (MASP) are evaluated and compared. The second step applies template matching algorithm to identify objects in the initial low-level segmentation as ventricles. Experiments for ventricle segmentation are conducted using a relatively large CT dataset containing mild and severe TBI cases., Results: Experiments show that the acceptable rate of the ideal midline detection is over 95%. Two measurements are defined to evaluate ventricle recognition results. The first measure is a sensitivity-like measure and the second is a false positive-like measure. For the first measurement, the rate is 100% indicating that all ventricles are identified in all slices. The false positives-like measurement is 8.59%. We also point out the similarities and differences between ICM and MASP algorithms through both mathematically relationships and segmentation results on CT images., Conclusion: The experiments show the reliability of the proposed algorithms. The novelty of the proposed method lies in its incorporation of anatomical features for ideal midline detection and the two-step ventricle segmentation method. Our method offers the following improvements over existing approaches: accurate detection of the ideal midline and accurate recognition of ventricles using both anatomical features and spatial templates derived from Magnetic Resonance Images.

Objectives: Interpretation of ventricular volume on computed tomography scans of hydrocephalus patients is usually subjective. The objective of this study was to determine whether radiological assessment of interval change correlates better with an objective calculated volume change or with other objective 2-dimensional estimates of ventricle volume change., Methods/sample: Ventricular volume, Evans ratio, and frontal and occipital Horn ratio were retrospectively assessed on 95 pairs of scans from patients with a ventriculoperitoneal shunt. To determine ventricle volume, all voxels of cerebrospinal fluid density were isolated on a 3-dimensional reconstructed computed tomography scan. Voxels of fluid density contiguous with one another in the ventricular system were isolated. Radiological assessments of interval change were divided into 5 groups based on reported findings in the radiology report. The 95% mean confidence intervals were developed for changes in the measured parameters, given a particular radiological assessment. Multinomial regression was subsequently performed to determine which parameter was most closely correlated with the radiological assessment., Results: Significant overlap was found in the confidence intervals for objectively calculated volume change between the different categories of radiological assessment. The frontal and occipital Horn ratio had the most consistent correlation with the radiological assessment, followed by the Evans ratio. Objectively calculated volume change correlated poorly with radiological assessment., Conclusions: Radiological interpretation does not correlate well with objectively calculated volume changes, but correlates better with other parameters that approximate volume and are likely used to visually evaluate interval change. We recommend that ventricle volume be objectively measured to increase consistency between radiological interpretation and actual interval changes.

Choroid plexus papilloma (CPP) is a rare benign tumor of the central nervous system with a propensity for location within the lateral ventricle in children. We report a case of a 14-year-old girl who presented with transient facial paresis and ataxia. Her imaging showed a non-enhancing intra fourth ventricular mass, the histology of which was reported as CPP. The atypical clinical and radiological features in this case are discussed. Choroid plexus papillomas should be considered in the differential diagnosis of non-enhancing fourth ventricular masses.

It is generally assumed that cerebrospinal fluid (CSF) is secreted in the brain ventricles, and so after an acute blockage of the aqueduct of Sylvius an increase in the ventricular CSF pressure and dilation of isolated ventricles may be expected. We have tested this hypothesis in cats. After blocking the aqueduct, we measured the CSF pressure in both isolated ventricles and the cisterna magna, and performed radiographic monitoring of the cross-sectional area of the lateral ventricle. The complete aqueductal blockage was achieved by implanting a plastic cannula into the aqueduct of Sylvius through a small tunnel in the vermis of the cerebellum in the chloralose-anesthetized cats. After the reconstitution of the occipital bone, the CSF pressure was measured in the isolated ventricles via a plastic cannula implanted in the aqueduct of Sylvius and in the cisterna magna via a stainless steel cannula. During the following 2 h, the CSF pressures in the isolated ventricles and cisterna magna were identical to those in control conditions. We also monitored the ventricular cross-sectional area by means of radiography for 2 h after the aqueductal blockage and failed to observe any significant changes. When mock CSF was infused into isolated ventricles to imitate the CSF secretion, the gradient of pressure between the ventricle and cisterna magna developed, and disappeared as soon as the infusion was terminated. However, when mock CSF was infused into the cisterna magna at various rates, the resulting increased subarachnoid CSF pressure was accurately transmitted across the brain parenchyma into the CSF of isolated ventricles. The lack of the increase in the CSF pressure and ventricular dilation during 2 h of aqueductal blockage suggests that aqueductal obstruction by itself does not lead to development of hypertensive acute hydrocephalus in cats.

Post-tubercular meningitic hydrocephalus (TBMH) and post-traumatic hydrocephalus (PTH) is often considered a contraindication for endoscopic third ventriculostomy (ETV), as it is mostly of communicating type in these cases. The aim of the present study was to define the role of ETV in patients with communicating hydrocephalus. Ten consecutive patients of TBMH, PTH and postneurocysticercus (NCC) hydrocephalus were formed the study group. Diagnosis of communicating hydrocephalus was made using magnetic resonance ventriculography (MRV). If contrast was seen coming out from the ventricular system into the basal cisterns, it was considered as communicating hydrocephalus. Patients with clinical and imaging evidence of raised intracranial pressure and failed medical treatment were taken up for ETV. All patients were studied by preoperative and postoperative MRV. Success of the procedure was assessed by the improvement in clinical and imaging parameters on postprocedure follow-up in all these cases. Technically successful ETV was performed in all 10 patients. Overall success rate of ETV in communicating hydrocephalus was 70% (n = 7). The shunt surgery was performed in the remaining three patients with ETV failure. One patient developed complication following postoperative MRV and was managed conservatively. We conclude that ETV is effective in post-TBM, post-traumatic communicating and post-NCC communicating hydrocephalus and should be considered as initial surgical option for cerebrospinal fluid diversion in these patients. MRV is a relatively safe technique to ascertain the patency of subarachnoid space as well as ETV stoma.

Purpose: The purpose of this study was to evaluate the association of asymmetric lateral ventricle (ALV) with clinical and structural pathologies and assess its clinical importance., Materials and Methods: We analyzed 170 consecutive ALV cases on computed tomography (CT) and 170 control group patients with normal head CT. Patients who had apparent etiologic causes for ALV were excluded. The differential diagnosis of ALV and unilateral hydrocephalus (UH) was made by using three different ventricle-brain ratios (VBRs). The measurements of the ALV were made at the frontal horn level. Patients with asymmetry were divided into three subgroups including mild, moderate and severe groups to eloborate the grade of the ventricular asymmetry. Additional CT findings including septal deviation, diffuse enlargement, atrophy and the densities of constant sites were also recorded systematically for each patient. Clinical and handedness data were collected and analyzed., Results: The prevalence of ALV in the study population was 6.1%. Headache was the most common reason for head CT examination and was significantly more common in the asymmetry group (61.7% in group A, 42.9% in group B, P = 0.001). Transient ischemic attack, focal neurologic findings, vertigo, ataxia, visual and hearing disturbances were similar in both groups (P > 0.5). There was no difference in smoking and alcohol habits in both patient groups. Ten (5.8%) patients in group A and 16 (9.4%) patients in group B had neuropsychiatric disorders, which did not achieve statistical significance. In group A patients, the larger ventricle was more common in the left side than in the right (left = 70.0%, right = 30.0%). Group A consisted of 57.0% mild (grade 1, n = 97), 26.5% moderate (grade II, n = 45) and 16.5% severe (grade III, n = 28) patients. There was no significant correlation between handedness and ALV. The density of different brain sites was found close similar on both sides in ALV and control group (P > 0.5). Choroidal cystic or solid neoplasm or periventricular dysplasia was detected in six ALV patients in group A (3.5%), on their additional MR examinations., Conclusion: The physician should not overlook an ALV finding on unenhanced CT, particularly in cases with severe degree of asymmetry or diffuse ventricular enlargement, and search for possible accompanying disorders.

Cerebrospinal fluid fistula secondary to head trauma is a potentially dangerous problem and precise localization and radical treatment is mandatory. The diagnostic technique is either computed tomography cisternography or MR cisternography. For evaluating the safety of diagnostic modalities and efficacy of treatment especially in terms of surgery, animal studies demonstrating traumatic cerebrospinal fistula model are indispensable not only for neurosurgeons but also for neuroradiologists. The authors in this paper describe a traumatic cerebrospinal fistula in an animal model using rabbits. The cerebrospinal fluid leakage was demonstrated successfully in all eight rabbits and was verified by computed tomography cisternography. The results led us to conclude that rabbit model of traumatic cerebrospinal fluid fistula is safe and has low mortality and morbidity rates. Further studies including larger number of animals should be considered in order to verify safety more accurately.

We present a case report of the findings of a left ventricular diastolic out pouching in a patient following acute myocardial infarction diagnosed by catheter left ventriculography and electrocardiography (ECG)-gated multidetector computed tomography (MDCT) findings. Left ventriculography demonstrated a small left ventricular diastolic out pouching, while MDCT enabled accurate evaluation of both left ventricular myocardium and lumen, establishing the diagnosis of an intramural small left ventricular pseudoaneurysm. This case illustrates the full capabilities of MDCT in the evaluation of left ventricular pseudoaneurysms.

The effects of leptomeningeal inflammation on the development of hydrocephalus are less understood than those of obstructing the flow of cerebrospinal fluid (CSF) in animal models. We succeeded in introducing a novel experimental model of hydrocephalus and analysed changes in histopathology and CSF flow in mice infected with an avirulent Fukaya strain of Toxoplasma gondii (T. gondii). Six to 7 week-old male mice were orally inoculated with a brain homogenate containing ten T. gondii cysts. The cerebral ventricles became enlarged in all C3H/HeN and C57BL/6 mice 4 weeks after T. gondii infection, but mildly in BALB/c mice. In addition to the lateral ventricle, the third and fourth ventricles and Sylvian aqueducts were dilated in all mice. Lymphocytes and monocytes infiltrated the subarachnoid space. Indian ink particles required more time to pass from the lateral ventricle to the cervical lymph nodes, although they reached the subarachnoid space. Computed tomography ventriculography demonstrated that the CSF was not obstructed during passage through the ventricular systems, but contrast remained static in the lateral ventricle only in infected mice. These results indicated that the infected mice developed communicating type hydrocephalus without obstructive or mass lesions in the ventricles. The hydrocephalus that arises in mice infected with T. gondii is considered a consequence of leptomeningeal inflammation that blocks CSF circulation at the subarachnoid space, implying that leptomeningeal inflammation is important in other types of hydrocephalus.

Recent research has suggested that the measurement of regional atrophy in the structure of the medial temporal lobe is a promising way to discriminate Alzheimer-type dementia patients from healthy control subjects. There are some reports that the inferior horns of the lateral ventricles are expanded by atrophying the structure of the medial temporal lobe. We developed a technique to automatically detect the region of the inferior horns of the lateral ventricles by gray-level thresholding and morphological processing. However, there were some incorrect regions in this method. Accordingly, we proposed a technique for which active contour models (ACM) were used. Our ACM incorporates the improved edge-based image and the external constraint to improve convergence and to reduce its dependence on initial estimation. In this study, we present the details of an algorithm that traces the contours of the inferior horns of the lateral ventricles and its performance relative to manual methods. The average degree of correspondence between the extract region and manual trace was measured in 30 inferior horns of 15 subjects. The average degree of correspondence of the proposed method was about 4% higher than that of the conventional method. These results suggest that the proposed method is more accurate than the conventional method.

Background and Purpose: Complex CSF diseases may be underdiagnosed or poorly understood on conventional CT or MR imaging. Although intrathecal CT cisternography with water-soluble iodinated contrast medium has been used, very few studies have dealt with the intrathecal use of gadopentate dimeglumine (Gd-DTPA), though it appears superior to CT. We report our experience with the intrathecal use of Gd-DTPA for MR cisternography and ventriculography in pediatric patients referred for study and treatment of complex CSF-related diseases., Materials and Methods: Ten patients (range, 1 month-16 years of age) were selected after we obtained specific informed consent. Intrathecal gadolinium injection was performed via transfontanelle ventriculostomy, ventriculoperitoneal shunt reservoir, or lumbar puncture. Cases included spontaneous CSF leaks (n=1), complex traumatic frontoethmoidal fractures with suspected CSF leak (n=2), multiloculated congenital or acquired hydrocephalus (n=3), intraventricular tumor (n=1), suspected postoperative arachnoiditis (n=1), complex midline defect (n=1), and acquired orbital meningoencephalocele (n=1)., Results: No patient showed biologic, behavioral, or neurologic alterations. In complex hydrocephalus or intraventricular cysts, ventriculography Gd-DTPA MR imaging helped to differentiate isolation of a ventricle or noncommunicating cyst in all 4 patients. In suspected posttraumatic CSF leaks, the procedure established with precision the place of the leak in 1 patient and excluded it in the other. In 1 patient who underwent surgery for spinal cord neoplasm, the procedure excluded arachnoiditis. In the other 3 patients with complex CSF-related diseases, the procedure showed distinctive radiologic findings for the understanding and treatment of the disease. Altogether, in 8 patients, imaging findings influenced or changed clinical decisions and surgical planning., Conclusions: Our preliminary results showed no side effects and potential useful clinical applications in the evaluation of CNS diseases involving the ventricular system or the subarachnoid space in selected pediatric patients.

Background: To our knowledge, the sensitivity of plain radiography, known as the shunt series, in diagnosing an etiology of ventriculoperitoneal (VP) shunt malfunction in children has not been previously investigated., Objective: To determine the accuracy of plain radiography in diagnosing VP shunt failure in children in whom shunt malfunction is clinically suspected., Materials and Methods: We retrospectively reviewed the charts of 238 children who had undergone plain radiographic examination for evaluation of clinically suspected VP shunt failure over a 5-year period. The results were compared with those of CT, MRI, and nuclear cisternography., Results: Just 6.72% of patients demonstrated plain radiographic signs of shunt failure. Of patients with normal plain radiographs, 43% demonstrated shunt abnormalities on CT, MRI or cisternography. Statistical analysis indicated that no more than 10.46% (P < 0.05) of plain radiographs showed signs of failure and that the sensitivity of plain radiography for the detection of VP shunt failure is no higher than 31%. Furthermore, there was poor agreement between the results of plain radiography and those of CT, MRI and cisternography., Conclusion: Children with clinically suspected VP shunt failure should proceed directly to cross-sectional or nuclear imaging, as plain radiographic examinations have low sensitivity and significant false-negative rates for detecting shunt abnormalities in all-comers. Use of the shunt series should be limited to patients who specifically have suspected mechanical causes of shunt failure.

Background: Spontaneous intraventricular hemorrhage is an infrequent but severe complication of hemorrhagic stroke. The conventional treatment of intraventricular hemorrhage consists of ventricular drainage or surgical evacuation, but neither of them is encouraged. The objective of this article is to compare different surgical procedures in order to evaluate a method of minimally invasive treatment for intraventricular hemorrhage., Methods: Neuroendoscopy was applied to treat 22 cases of intraventricular hemorrhage. Twenty cases of the same disease that were treated by external ventricular drainage were taken as a control and comparison., Results: All patients were followed up for 2 months. In the neuroendoscopy group, according to the Glasgow outcome scale, the result was excellent in 5 cases, good in 9, fair in 4, poor in 2 and death in 2. In the external ventricular drainage group, the result was excellent in 1 case, good in 5, fair in 7, poor in 5 and death in 2. More patients in the neuroendoscopy group showed good recovery after 2 months of surgery (p < 0.05). The difference in mortality rate between the 2 groups was not statistically significant (p > 0.05)., Conclusions: Neuroendoscopic neurosurgery for intraventricular hemorrhage offers better surgical treatment because it is characterized by visualized manipulation, effective hemorrhage evacuation and excellent postoperative outcomes.

Background: The specificity of cerebrospinal fluid (CSF) dynamics in the immature brain still remains unknown. In our data previously published, the transependymal intraparenchymal CSF pathway (the minor pathway) plays a significant role in various degrees in the alternative CSF passage. Now, there is a growing consensus in the age differences in the outcome of neuroendoscopic ventriculostomy in treatment of non-communicating types of hydrocephalus. The authors discuss the clinical significance of the specific CSF dynamics and propose the new aspect of classification of hydrocephalus with a theory in the development of CSF from the pathophysiological point of view., Patients and Methods: Between January 2001 and March 2004, 122 hydrocephalic children were registered at the Jikei University Hospital Women's & Children's Medical Center (JWCMC), Tokyo. Our retrospective study for the efficacy of neuroendoscopic ventriculostomy confirmed the significantly high failure rate of neuroendoscopic ventriculostomy in treating hydrocephalus in neonates and infants with non-communicating hydrocephalus as the initial impression. The prospective CSF dynamic studies using cine-mode MRI and CT ventriculo-cisternography were then routinely started. Altogether, 9 out of 29 (31%) endoscopically treated cases needed shunt placement 3-30 weeks (mean 7.9 weeks) after the endoscopic procedure(s) (publication in preparation). Five out of 11 (45%) neonates/infants under 3 months, 3/5 (60%) infants at 7-12 months, 10/10 (100%) toddlers at 1-4 years and 3/3 (100%) schoolchildren at 5-17 years were cured, as in the condition of "post-endoscopic ventriculostomy arrested hydrocephalus". The pattern of ventriculo-cisternography in neonatal/infantile cases revealed intraparenchymal predominant pattern (minor pathway) of the CSF dynamics rather than passage in the major pathway., Discussion: The various basic investigations in rodents, cats and monkeys have suggested that CSF is absorbed not via Pacchionian bodies as the last end of the major pathway, which do not exist in these animals and are recognized after infantile period in human, but through the choroids plexus and the periventricular fenestrated venous capillaries into the deep venous channel. The high incidence of "failure to arrest hydrocephalus" by neuroendoscopic ventriculostomy in fetal, neonatal and infantile periods was considered to depend on the specific CSF dynamics, in which the major CSF pathway has not developed and the minor pathway has a significant role. PROPOSAL OF THEORY: We herein propose a new aspect of classification for hydrocephalus with special reference to the CSF circulation in the minor CSF pathway, i.e. "minor pathway hydrocephalus", differentiating the conventional classification by Dandy (communicating and non-communicating) or Russell (non-obstructive and obstructive) as "major pathway hydrocephalus". We also herein propose a hypothesis that the CSF dynamics develop in the theory of evolution from the immature brain, as in the animals with the minor CSF pathway predominance, towards matured adult human brain together with completion of the major CSF pathway: the "evolution theory in CSF dynamics".