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Rhg4 is a major genetic locus that contributes to soybean cyst nematode (SCN) resistance in the Peking-type resistance of soybean ( Glycine max ), which also requires the rhg1 gene. By map-based cloning and functional genomic approaches, we previously showed that the Rhg4 gene encodes a predicted cytosolic serine hydroxymethyltransferase (GmSHMT08); however, the novel gain of function of GmSHMT08 in SCN resistance remains to be characterized. Using a forward genetic screen, we identified an allelic series of GmSHMT08 mutants that shed new light on the mechanistic aspects of GmSHMT08 -mediated resistance. The new mutants provide compelling genetic evidence that Peking-type rhg1 resistance in cv Forrest is fully dependent on the GmSHMT08 gene and demonstrates that this resistance is mechanistically different from the PI 88788-type of resistance that only requires rhg1 We also demonstrated that rhg1-a from cv Forrest, although required, does not exert selection pressure on the nematode to shift from HG type 7, which further validates the bigenic nature of this resistance. Mapping of the identified mutations onto the SHMT structural model uncovered key residues for structural stability, ligand binding, enzyme activity, and protein interactions, suggesting that GmSHMT08 has additional functions aside from its main enzymatic role in SCN resistance. Lastly, we demonstrate the functionality of the GmSHMT08 SCN resistance gene in a transgenic soybean plant., (© 2017 American Society of Plant Biologists. All Rights Reserved.)

Social support research suggests romantic partners could play a vital role in the success of individuals' weight management (WM) efforts, but contradictory findings from previous research have impeded our understanding of how romantic partners influence weight management goal attainment. Employing a confirmation perspective, overweight participants (body mass index [BMI] greater than 25) who were actively trying to manage their weight (N = 53) were asked to respond to daily questionnaires for a period of 2 weeks regarding their interactions with their romantic partner. Diet, exercise, and general weight management goal accomplishment were assessed. HLM was employed to assess the independent and interactive effects of partner acceptance and challenge on each of these goals. Findings suggest that perceiving high levels of both acceptance and challenge from partners was associated with more general WM and diet goal accomplishment. However, greater attainment of exercise goals was associated with only challenge. Fluctuations in partner acceptance and challenge were also examined to determine whether consistency in confirmation behaviors was associated with WM goals. Hierarchical regressions revealed that fluctuations in acceptance, but not challenge, were linked with goal attainment. Specifically, fluctuations in acceptance were helpful for those whose partners were perceived to exhibit lower levels of acceptance, but fluctuations were detrimental for those whose partners exhibited greater acceptance. Implications for communication among couples in which one partner is attempting to lose weight are discussed.

Background: The neuropathological consequences of Gamma Knife radiosurgery (GK) on hypothalamic hamartoma (HH) are unknown., Objective: In a cohort of patients undergoing surgery for treatment-resistant epilepsy, we compared surgically resected HH tissue from patients without (group I; n = 19) and with (group II; n = 10) a history of GK (median dose 16 Gy to the 50% isodose margin)., Methods: Techniques included thick-section stereology for total nucleated and total neuron cell counts, and thin-section immunohistochemistry. Normal human hypothalamus derived from age-matched autopsy material was used as control tissue for CD68 immunohistochemistry. Qualitative scoring of tissue sections was performed by a neuropathologist who was blind to the GK treatment history., Results: GK is associated with decreased total cell density (p < 0.02). A dose-dependent association of GK with decreased total neuron density approached significance (p = 0.06). Group II HH tissue had significantly more (1) reactive gliosis, (2) thickened capillary endothelium and (3) microglial activation. Degenerative features, including karyorrhexis and pyknotic nuclei, were infrequent in group II and absent in group I HH tissue., Conclusions: Nonnecrotizing doses of GK radiosurgery decrease cell density in human HH tissue. Cell loss resulting from GK may contribute to decreased excitation in the neuronal networks responsible for seizure onset in HH tissue., (Copyright © 2012 S. Karger AG, Basel.)

Object: This study aimed at identifying outcomes with respect to seizures, morbidity, and mortality in adult patients undergoing resective or Gamma Knife surgery (GKS) to treat intractable epilepsy associated with hypothalamic hamartoma (HH)., Methods: Adult patients undergoing surgical treatment for HH-related epilepsy were prospectively monitored at a single center for complications and seizure outcome by using a proprietary database. Preintervention and postintervention data for patients 18 years of age and older, and with at least 1 year of follow-up, were analyzed, with specific attention to seizure control, complications, hormonal status, and death., Results: Forty adult patients were found in the database (21 were women). The median HH volume was 0.54 cm(3). In 70% of patients, it was located inside the third ventricle, attached unilaterally and vertically to the hypothalamus (Delalande Type II). Most patients (26) underwent an endoscopic resection, 10 patients had a transcallosal or other type of open (pterional or orbitozygomatic) resection, and 4 patients chose GKS. Twenty-nine percent became seizure free in the long term, and overall a majority of patients (55%) reported at least > 90% seizure improvement. Only 3 patients were ultimately able to discontinue anticonvulsants, whereas most patients were taking an average of 2 antiepileptic drugs pre- and postoperatively. The only factor significantly correlated with seizure-free outcome was the absence of mental retardation. The HH volume, HH type, and amount of resection or disconnection were not correlated to seizure freedom. A total of 4 patients (10%) died, 2 immediately after surgery and 2 later. All of them had undergone a resection, as opposed to GKS, and still had seizures. Postoperatively, persistent neurological deficits were seen in 1 patient; 34% of patients had mild hormonal problems; and 59% experienced weight gain of at least 6.8 kg (average gain 12.7 kg)., Conclusions: Surgical or GKS procedures in adults with HH provided seizure freedom in one-third of patients. The only significant favorable prognostic factor was the absence of mental retardation. The overall mortality rate was high, at 10%. Other important morbidities were persistent hormonal disturbances and weight gain.

Purpose: Hypothalamic hamartomas (HHs) are a malformation of the ventral hypothalamus and tuber cinereum, associated with gelastic seizures and epilepsy. We sought to determine the spectrum of electroencephalography (EEG) abnormalities in a large cohort of HH patients., Methods: Data was collected for HH patients undergoing evaluation between 2003 and 2007. Data included seizure history, prior treatment, and results of diagnostic studies. After informed consent, data were entered into a database., Key Findings: We reviewed 133 HH patients. Mean age at time of data analysis was 15.7 years (59.4% male). Most patients had gelastic (77%) and/or complex partial seizures (58%). Records for 102 EEG studies on 73 patients were reviewed. Interictal epileptiform abnormalities were seen in 77%, localizing predominately to the temporal and frontal regions. Records for 104 video-EEG (VEEG) studies on 65 patients were reviewed. Of 584 gelastic seizures (GS) captured, no ictal EEG change was noted in 438 (75%). Of GS with localizing features, 89% suggested onset from the temporal and/or frontal regions. There were 160 complex partial seizures (CPS). For those with localizing features, 100% localized to the temporal and/or frontal head regions. EEG and VEEG findings correlated with the side of HH attachment. VEEG did not influence outcome., Significance: EEG features in HH patients are diverse. The majority of gelastic seizures fail to demonstrate change in the EEG. The lack of EEG changes with many clinical seizures, and the false localization seen in those events with an ictal change suggest the utility of EEG is limited in the evaluation of these patients., (Wiley Periodicals, Inc. © 2011 International League Against Epilepsy.)

Purpose: This study aims to examine the outcomes of ten patients after orbitozygomatic (OZ) pterional surgery in cases of refractory epilepsy caused by hypothalamic hamartomas (HH)., Methods: Ten patients with HH and treatment-resistant epilepsy (mean age 18.3 years, range 0.7 to 42.7) underwent HH resection with an OZ approach (n = 8) or an OZ approach combined with a transventricular endoscopic approach (n = 2). Follow-up for the patients ranged from 0.5 to 6.2 years (mean 3.1). Outcomes were prospectively monitored with the use of a proprietary database., Results: Four patients (40%) are seizure-free, and four (40%) have had greater than 50% reduction in seizures. One patient had no significant change in seizure frequency, and one patient died unexpectedly 2.8 years after surgery. Six patients had total or near-total HH resection (98-100% of HH lesion volume). Of these, four of six (66%) were seizure-free, and two had at least greater than 50% reduction in seizures. Residual complications include diabetes insipidus (n = 1), poikilothermia (n = 1), visual field deficit (n = 1), and hemiparesis (n = 1). Eight families (80%) reported improved quality of life., Conclusions: Patients with treatment-resistant epilepsy and tumors with an inferior or horizontal plane of attachment to the hypothalamus should continue to be approached from below. Those with both intrahypothalamic and parahypothalamic components may require approaches from above and below, either simultaneously or staged. For appropriately selected patients, the success of controlling seizures with an OZ is comparable to results utilizing transcallosal or transventricular approaches. The likelihood of controlling seizures appears to correlate with extent of resection.

Objective: The goal of the work described here was to examine the relationship between intellectual test performance in patients with hypothalamic hamartoma (HH) with refractory epilepsy and their seizure histories, as well as the size and neuroradiographic anatomical features of the HH. It was predicted that the level of estimated intelligence and the pattern of intellectual test performance would significantly correlate with the size of the HH and neuroanatomical features., Method: In this cross-sectional design study, 49 patients with HH between the ages of 5 and 55 years were classified by age at time of examination, as well as pattern of performance on the Wechsler intelligence scales. All patients were included in data analysis irrespective of their ability to participate in psychometric testing. Patients with a prior history of neurosurgical treatment were excluded., Results: For those patients functionally capable of participating in cognitive testing (n=42), a summary index score, which estimated level of intellectual function (composed of the Vocabulary, Block Design, and Coding subtests of the Wechsler intelligence scales), was significantly correlated only with number of antiepileptic drugs (AEDs) the patient was taking at the time of evaluation (r=-0.66, n=38, P=0.05). In contrast, a categorization method addressing the pattern of intellectual test performance (including those patients who were not functionally capable of participating in cognitive testing, n=49) was significantly correlated with number of AEDs (r=+0.35, n=48, P=0.01), size of HH (r=+0.38, n=49, P=0.01), presence of precocious puberty (PP: r=+0.41, n=49, P=0.01), and anatomical classification of HH (r=+0.39, n=49, P=0.01)., Conclusions: The findings confirm the wide range of cognitive functioning in the population of patients with HH and refractory epilepsy, and suggest that multiple variables are correlated with intellectual test performance in patients with HH with refractory epilepsy. Although the present cross-sectional design study does not answer the question of whether or not epilepsy severity produces lower intelligence in this patient population, number of AEDs and neuroanatomical features of the HH lesion are identified as being significantly related to cognitive performance in this patient sample.

Purpose: A small number of patients with hypothalamic hamartoma (HH) present with infantile spasms (IS) as an initial or early seizure type. We describe the clinical features of IS associated with HH., Methods: Our series of patients with HH and epilepsy was reviewed to identify cases with a history of IS. The clinical features and neuroradiological findings in this study group were compared to a control group of patients with HH and refractory epilepsy, but without a history of IS., Results: We identified six patients with HH and a history of IS in this series (n = 122, 4.9%). Five of the six are male. Four of the six patients (67%) developed IS as their first seizure type. The mean age for onset of IS was 6.2 months (range 4-9 months). Results of electroencephalographic (EEG) study at the time of IS diagnosis showed hypsarrhythmia in two (33%). Five patients were treated with adrenocorticotropic hormone (ACTH), and four of the five (80%) responded with control of IS. However, these patients developed other seizure types, and were ultimately refractory to medical management. Aside from the IS, no significant differences in clinical and imaging features were determined between the study group and the control group., Conclusions: HH should be included in the differential diagnosis for infants presenting with IS. These patients may have hypsarrhythmia on initial EEG, and may respond to ACTH treatment with improvement of IS. However, all became refractory with other seizure types, more commonly seen in HH patients. Focal pathologies associated with IS may be subcortical, as well as cortical, in nature. We have not identified any predictive features for the occurrence of IS in the HH population.

Background and Purpose: Commercially available software programs for the conversion of dynamic CT perfusion (CTP) source data into cerebral blood volume (CBV), cerebral blood flow (CBF), and mean transit time (MTT) maps require operators to subjectively define parameters that are used in subsequent postprocessing calculations. Our purpose was to define the variability of CBV, CBF, and MTT values derived from CTP maps generated from the same source data postprocessed by three different CT technologists (CTTs)., Methods: Raw data derived from dynamic CTP examinations performed in 20 subjects were postprocessed seven times by three experienced CTTs. Parenchymal regions of interest derived from each map (CBV, CBF, and MTT) were compared. The CBF maps generated by each technologist were also qualitatively assessed. Decisions made by each analyzer during postprocessing were assessed., Results: The intraclass correlation coefficients were 0.73 (95% CI, 0.64-0.81), 0.87 (0.83-0.91) and 0.89 (0.85-0.93), for the CBV, CBF, and MTT parenchymal regions of interest, respectively. All individual correlation coefficients between data sets were significant to a P value <.05. Measurement error, made solely on the basis of different technologists postprocessing the same source data and expressed as the coefficients of variation, were 31%, 30%, and 14% for CBV, CBF, and MTT, respectively. The selection of the arterial input function (AIF) region of interest, venous function region of interest, and preenhancement interval were very reproducible. The technologists differed significantly with respect to the selection of the postenhancement image (PoEI) (P <.01). A retrospective review of the individual CBF maps indicated that variance in the PoEI selection accounted for much of the variation in the qualitative appearance of the CBF maps generated by different technologists. The PoEI was selected to demarcate the baseline of the AIF time-attenuation curve. It is likely that this method of PoEI selection significantly contributed to intra- and interanalyzer variability., Conclusion: There is a high degree of correlation between parenchymal regions of interest derived from CBV, CBF, and MTT maps generated from the same dynamic CTP source data postprocessed by different operators. The level of agreement, however, may not be sufficient to incorporate quantitative values into clinical decision making. Quantitative differences between parenchymal regions of interest were not infrequently manifest as significant differences in the qualitative appearance of the CBF maps. It is likely that, with optimization of postprocessing parameter selection, the degree of variability may be substantially reduced.

We evaluated 13 children with cerebral palsy who had birthweights under 1085 g. A magnetic resonance image (MRI) of the head was obtained, the findings were compared, and the neonatal records were reviewed. The individual children were classified as to the type of cerebral palsy. On MRI, all had severe injury to the inferior cerebellar hemispheres, mostly symmetric, and in some there was injury to the inferior vermis. The average birthweight was 668 g, and the gestational ages were 24 to 27 weeks. No other outstanding prenatal or postnatal problems were identified. The children had different types of severe cerebral palsy, with only 3 being able to walk. Almost all were mentally retarded and microcephalic. All had visual problems. This report defines a previously underappreciated injury to the cerebellum in extremely premature infants. Further clinical, laboratory, and pathologic studies are needed to better define the underlying mechanisms.

Posttraumatic syringomyelia as a cause of progressive neurologic deterioration has been well described. More recently, the noncystic posttraumatic tethered cord has been associated with identical progressive neurologic deterioration. A retrospective analysis of patients treated surgically with spinal cord untethering and/or cyst shunting to arrest a progressive myelopathy from a posttraumatic tethered and/or cystic cord was performed. Emphasis was on outcome using the American Spinal Injury Association (ASIA) sensory and motor scoring systems. During an 18-month period from May 1993 to December 1994, 70 patients with spinal cord injury were operated upon for tethered and/or cystic spinal cords because of a progressive myelopathy and deteriorating ASIA sensory/motor scores. Fifty-nine patients had follow-up data 1 year postoperatively. At the 1 year follow-up, there was small improvement in light touch sensory scores (0.67 points), pinprick scores (1.3 points), and motor scores (0.41 points) demonstrating that the progression of the myelopathic process was arrested. Thirty-four of these 59 patients had no previous surgery to their spinal cords. At 1 year follow-up, light touch scores improved on average 2.38 points, pinprick scores 3.88 points (p < 0.05), and motor scores 1.47 points, suggesting better outcome with first-time surgery. Of this latter group, 64.3% regained a lost function, 62.5% saw improvement in spasticity, 55.6% had substantial improvement in neurogenic pain, and 95.8% felt that surgery prevented further neurologic deterioration.

Objective: The goal was to determine the safety and efficacy of absolute ethyl alcohol treatment in the management of intra-axial brain arteriovenous malformations (AVMs)., Methods: Seventeen patients (eight female and nine male patients; mean age, 41 yr) underwent ethanol endovascular therapy for treatment of their brain AVMs. Superselective amytal testing preceded all procedures. Neuroleptic intravenous anesthesia was used for 16 patients, and general anesthesia was used for 1 patient. Follow-up monitoring consisted of clinical evaluations, magnetic resonance imaging, and arteriography., Results: In follow-up evaluations (mean follow-up period, 13 mo) after embolization of brain AVMs, neither vascular recanalization nor the neovascular recruitment phenomenon was observed in any patient. Progressive AVM thrombosis at arteriographic follow-up evaluation was a constant feature. Seven patients were cured of their AVMs with ethanol endovascular therapy alone. Three patients were cured of their lesions with ethanol embolization plus surgical resection. One patient was cured of his lesion with ethanol embolization and radiation therapy of the residual nidus. Three patients underwent only partial therapy, with significant improvement in symptoms. Three patients are currently undergoing ethanol endovascular therapy. Complications occurred with 8 of 17 patients, most of which were transient. Two patients died because of late subarachnoid hemorrhages, one patient 4 months and one patient 14 months after partial therapy., Conclusion: Progressive and permanent AVM occlusion is a common finding in arteriographic follow-up evaluations. In no patients did arterial recanalization or the neovascular recruitment phenomenon occur. Our initial results indicate that ethanol has a permanence that is seldom encountered with other embolic agents. With aggressive decadron therapy, the complications related to swelling in the brain are largely reversible.

Objective: To review the clinical features, radiographic findings, and programming strategies used in our population of patients who developed facial nerve stimulation after cochlear implantation., Study Design and Setting: Patients referred to our nonprofit, outpatient facility were studied prospectively., Patients: The study consisted of 14 patients with facial nerve stimulation after placement of the Nucleus 22-channel cochlear implant., Interventions: Records were reviewed retrospectively, and patients were studied with three-dimensional computed tomographic scanning techniques. Electrical testing was performed, and various cochlear implant programming strategies were evaluated., Main Outcome Measures: Important clinical features were reviewed. The radiographic and anatomical relationships of the facial nerve to the cochlea were evaluated, and the programming strategies used to effectively control facial nerve stimulation were reviewed., Results: Prevalence of facial nerve stimulation in our population was 7%. The most common cause was otosclerosis. Anatomical data confirmed the close proximity of the basal turn of the cochlea and the labyrinthine segment of the facial nerve. There was a high correlation between the electrodes causing symptoms and those found radiographically to be closest to the labyrinthine segment of the facial nerve. We were able to control facial nerve stimulation in all patients through programming mode changes., Conclusions: Otosclerosis appears to be a risk factor for developing facial nerve stimulation after cochlear implantation, and the site of stimulation appears to be the labyrinthine segment of the facial nerve. Familiarity with more elaborate programming techniques is critical to managing patients with this complication.

An interesting case is reported of an 11-year-old girl who experienced a sudden, profound right-sided hearing loss at the age of 5 years after hearing a "pop" and the sound of rushing water in her right ear. At that time the patient was thought to have Mondini's deformity, and a perilymphatic fistula of the oval window in the right ear. Six years later she was diagnosed with a juvenile pilocytic astrocytoma of the pons with an exophytic component extending into the cerebellopontine angle. Of particular interest in this case is the presence of evoked otoacoustic emissions in the right ear with a profound neural hearing loss. The presence of transient evoked and distortion product otoacoustic emissions confirmed normal sensory outer hair cell function and an intact peripheral auditory system in a clinically deaf ear, thus indicating hearing loss due to a neural component instead of a sensory component, which was previously assumed.

Two patients with congenital dermoids of the eustachian tube presented with recurrent otitis media and chronic otorrhea resistant to antimicrobial therapy. CT demonstrated fat density, homogeneous lesions, filling and expanding the eustachian tube. On MR, signal from the lesions was consistent with fat, and the relationship with the internal carotid artery was better delineated than by CT. Microscopically, the masses consisted of a conglomeration of ectodermal and mesodermal elements.

The case is reported of meningioangiomatosis of the brain stem in a 3 1/2-year-old girl who suffered from vomiting, left facial weakness, difficulty in swallowing, and ataxia. This is believed to be the first reported case of meningioangiomatosis in the brain stem. Computerized tomography showed an intensely enhancing hyperdense mass in the left restiform body. Magnetic resonance imaging revealed that the lesion was isointense to gray matter on the T1-weighted image and hypointense on the T2-weighted image, with a surrounding zone of high T2 signal and intense enhancement. Angiography was normal. Surgical exploration demonstrated an intramedullary firm mass that was partially resected. Histologically, the mass consisted of a low-grade lesion of meningeal origin with spindle cells in a whorling pattern that were occasionally focused around small vessels. On 2-year follow-up imaging, the lesion remains unchanged in size. Certain particularities of this lesion are discussed in the context of the literature.

The acquired descent of the cerebellar tonsils radiographically indistinguishable from Chiari I malformations has been previously reported. The relationship between lumbar shunting procedures for hydrocephalus and symptomatic Chiari malformations has been established. We report the cases of 10 children with lumboperitoneal shunts in whom previous radiographic studies had confirmed a normal hindbrain configuration. Seven of the 10 patients acquired tonsillar descent into the foramen magnum, detected by magnetic resonance imaging, whereas the others remained normal. Four of seven patients were symptomatic; two underwent the removal of the lumboperitoneal shunt and conversion to a ventriculoperitoneal shunt, and two underwent posterior fossa decompression. Further magnetic resonance imaging revealed that one of the two patients who underwent conversion shows ascent of the cerebellar tonsils. All four patients became asymptomatic less than 6 months after treatment. In this article, we discuss seven cases of acquired Chiari malformations and the complete reversal of an acquired Chiari malformation after surgical treatment, as documented by magnetic resonance imaging. Cases of asymptomatic acquired Chiari malformations are reported, including those resulting from shunting for intracranial hypertension without hydrocephalus. We conclude that a craniospinal pressure gradient creates a potential for cerebellar tonsil descent and recommend that ventriculoperitoneal shunting be performed in children with communicating hydrocephalus to avoid this potential complication. We also recommend annual surveillance of the cervicomedullary junction in children with lumboperitoneal shunting. Finally, if symptomatic tonsillar descent occurs from lumbar shunting, a trial conversion to ventriculoperitoneal shunting may eliminate the need for posterior fossa decompression.

Our objective was to determine the incidence rate of stroke and stroke subtypes in children. We reviewed the medical records, autopsy records, and brain imaging studies of all children with a possible stroke within the Greater Cincinnati metropolitan area population of nearly 1.3 million during 1988 and 1989. Traumatic brain hemorrhages and germinal matrix hemorrhages were excluded. Of the 295,577 children in Greater Cincinnati, medical records of 178 children were screened. Sixteen cases (13 whites and three blacks) less than age 15 years fit strictly defined criteria for first-ever stroke. The incidence rate for cerebral infarction was 1.2 cases per 100,000 (95% confidence interval, 0.3 to 2.0). The combined incidence rate for intracerebral hemorrhage and subarachnoid hemorrhage was 1.5 cases per 100,000 children (95% confidence interval, 0.4 to 2.3). The incidence rate of all stroke in white children was 2.6 cases per 100,000 (95% confidence interval, 1.2 to 4.1), compared to 3.1 per 100,000 in black children (95% confidence interval, 0 to 6.6). The combined 30-day mortality for intracerebral hemorrhage and subarachnoid hemorrhage was 22% (two of nine) compared to 14% (one of seven) for cerebral infarction. We conclude that in contrast to the picture in adults, hemorrhagic stroke among infants and children is at least as common as ischemic infarction.

In the literature, clinical descriptions of sigmoid sinus thrombosis occurring after closed head injury in children are rare. One to 5 days after trauma to the back of the head, five children (aged 1 to 7 yr) presented with gait ataxia, vomiting, and headache. Trauma was mild in four children. Computed tomography of all the children, performed within 5 days after the injury, showed focal hyperdensity in the region of the left sigmoid sinus. Four children had extra-axial hyperdense collections along the left transverse sinus, and three had skull fractures adjacent to the left sigmoid sinus. Magnetic resonance imaging (MRI) of all the children, performed 2 to 6 days after injury, showed left sigmoid-sinus thrombosis and decreased flow or thrombosis within the lateral third of the left transverse sinus. All the children had MRI scans 4 to 6 weeks after their diagnosis and were followed up for 1 to 12 months. In four children whose symptoms subsided completely within 2 to 10 weeks, MRI showed recanalization of the sigmoid sinus within 4 to 6 weeks after injury. In one child whose symptoms resolved after 6 months, sigmoid-sinus thrombosis persisted with the formation of collateral flow. We conclude that traumatic sigmoid-sinus thrombosis should be suspected when a child has persistent or delayed gait ataxia and vomiting after injury to the back of the head. Computed tomography characteristically demonstrated focal hyperdensity within the sigmoid sinus that we term the dense sigmoid-sinus sign. Because the sinus recanalized and the symptoms subsided in most children within 6 weeks, we conclude that prophylactic medical or surgical intervention is not indicated.

Choroid plexus neoplasms (CPN) are rare tumors occurring with a relative incidence of 0.5% of intracranial neoplasms in all age groups and 1.5-6.4% of all pediatric brain tumors. In children, the most common site of origin is the atria of the lateral ventricles where the CPN may represent either a carcinoma or a benign papilloma. CPN arising in the fourth ventricle are more common in adults, and are more likely to represent a benign papilloma. We present 2 children with CPN arising from the inferior fourth ventricle with similar features on MRI, one of which represented a benign papilloma and the other a malignant carcinoma. CPN should be included, even in young children, in the differential diagnosis of any infratentorial, intraventricular tumor.

Three-dimensional images of the cerebral ventricles may now be generated from routine serial axial or coronol noncontrast CT scans in 5-8 min and rotated in space interactively in 2-5-s to provide the physician with useful views of anatomic relationships difficult to depict in other ways.