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- An Integrated Mechanism of Pediatric Pseudotumor Cerebri Syndrome: Evidence of Bioenergetic and Hormonal Regulation of Cerebrospinal Fluid Dynamics. [JOURNAL ARTICLE]
- Pediatr Res 2014 Nov 24.
Pseudotumor cerebri syndrome (PTCS) is defined by the presence of elevated intracranial pressure (ICP) in the setting of normal brain parenchyma and cerebrospinal fluid (CSF). Headache, vision changes, and papilledema are common presenting features. Up to 10% of appropriately treated patients may experience permanent visual loss. The mechanism(s) underlying PTCS is unknown. PTCS occurs in association with a variety of conditions, including kidney disease, obesity, and adrenal insufficiency, suggesting endocrine and/or metabolic derangements may occur. Recent studies suggest that fluid and electrolyte balance in renal epithelia is regulated by a complex interaction of metabolic and hormonal factors; these cells share many of the same features as the choroid plexus cells in the CNS responsible for regulation of CSF dynamics. Thus, we posit that similar factors may influence CSF dynamics in both types of fluid-sensitive tissues. Specifically, we hypothesize that, in patients with PTCS, mitochondrial metabolites (glutamate, succinate) and steroid hormones (cortisol, aldosterone) regulate CSF production and/or absorption. In this integrated mechanism review, we consider the clinical and molecular evidence for each metabolite and hormone in turn. We illustrate how related intracellular signaling cascades may converge in the choroid plexus, drawing on evidence from functionally similar tissues.Pediatric Research (2014); doi:10.1038/pr.2014.188.
- Effects of lowering cerebrospinal fluid pressure on the shape of the peripapillary retina in intracranial hypertension. [JOURNAL ARTICLE]
- Invest Ophthalmol Vis Sci 2014 Nov 18.
Purpose:To analyze the deformations of the peripapillary retinal pigment epithelial basement-membrane (ppRPE/BM)-layer in response to procedures that lower intracranial pressure(ICP). Second, to demonstrate how shape changes may complement the mean retinal nerve fiber layer(RNFL)-thickness as a measure of intracranial hypertension(ICH) and papilledema. Methods:We used Geometric Morphometrics on SD-OCT images to analyze shape change of the ppRPE/BM-layer after several interventions that lower cerebrospinal fluid(CSF) pressure. We also evaluated the effects of intervention on anterior - posterior displacement of ppRPE/BM and the mean RNFL thickness. Forty-one patients with ICH and papilledema were studied before and after lumbar puncture(20), CSF-shunt(9) and medical treatment of idiopathic ICH(23). We also compared shape of 30 normal subjects to 23 patients whose papilledema resolved after medical treatment. Results:The ppRPE/BM-layer in ICH and papilledema is characterized by an asymmetric anterior deformation that moves posteriorly and becomes more V-shaped after each pressure-lowering intervention. The differences were statistically significant for all three groups. These shape changes also occur in patients without papilledema who have secondary optic atrophy. Posterior displacement at the margin of the ppRPE/BM layer correlated strongly with overall shape changes. Conclusions:The subsurface contour of the ppRPE/BM-layer is a dynamic property that changes with CSF pressure-lowering interventions. It can supplement the RNFL-thickness as an indirect gauge of ICP and is particularly helpful in patients with secondary optic atrophy. Direct measurements of displacement at the basement membrane opening may serve as a more convenient office-based surrogate for shape analysis.
- [Bilateral papilledema revealing benign intracranial hypertension]. [Journal Article]
- Pan Afr Med J 2014.:96.
- Cerebral Venous Thrombosis in the Absence of Headache. [JOURNAL ARTICLE]
- Stroke 2014 Nov 6.
Although headache is the most common symptom in cerebral venous thrombosis, 5% to 30% of patients do not report headache at baseline. Characteristics of these patients have not been investigated.In post hoc analysis of the International Study on Cerebral Vein and Dural Sinus Thrombosis study, patients who might not have been able to report headache (aphasia, stupor, coma, or mental status disorder) were excluded.Three hundred eighty-two of the original 624 patients (61%) were included, of whom 38 (10%) did not report headache at baseline. Patients without headache were older (mean age, 45 versus 37; P=0.001) and less often female (63% versus 77%; P=0.06). Paresis (42% versus 27%; P=0.05) and seizures (58% versus 32%; P=0.001) were more common in patients without headache, whereas papilledema was less common (8% versus 35%; P=0.001). Isolated cortical vein thrombosis (16% versus 2%; P=0.001), brain parenchymal lesions (66% versus 46%; P=0.02), and malignancies (18% versus 6%; P=0.009) were more common among patients without headache. Outcome at last follow-up was worse in patients without headache (modified Rankin Scale, 0-1; 76% versus 89%; P=0.04; mortality, 13% versus 5%; P=0.05), but after adjustment for prognostic variables, headache was not an independent predictor of outcome.Patients with cerebral venous thrombosis but without headache are a heterogeneous subgroup, in which older patients, men, and some associated conditions are over-represented. Patients without headache had a worse clinical outcome, but after adjustment for imbalances, headache was not an independent predictor of outcome.
- Colloid Cyst of the Third Ventricle Presenting with Features of Terson's Syndrome. [Journal Article]
- Middle East Afr J Ophthalmol 2014 Oct; 21(4):344-6.
This report describes a middle-aged man presenting to the ophthalmologist with history of seeing floaters before both eyes since 2-weeks duration. A history of intermittent headache and dizziness of recent onset was elicited on questioning. Ocular examination showed bilateral early papilloedema and mild vitreous hemorrhage. Brain computed tomography (CT) disclosed features suggestive of colloid cyst of the third ventricle in the region of foramen of Monro with moderate hydrocephalus. Emergency craniotomy and excision of the cyst was done, and the patient is doing well for the last 18 months after the surgical intervention. The mechanism of this presentation, importance of early investigations, and timely intervention are highlighted in order to avoid serious neurological sequelae. The literature was extensively reviewed for atypical presentations of intraventricular colloid cyst.
- Baseline OCT Measurements in the Idiopathic Intracranial Hypertension Treatment Trial: Part II. Correlations and Relationship to Clinical Features. [JOURNAL ARTICLE]
- Invest Ophthalmol Vis Sci 2014 Nov 4.
Purpose: The accepted method to evaluate and monitor papilledema, Frisén grading, is an ordinal approach based on descriptive features. Part I showed spectral domain (SD) optical coherence tomography (OCT) in a clinical trial setting provides reliable measurement of the effects of papilledema on the optic nerve head (ONH) and peripapillary retina, particularly if a 3D-segmentation method is used for analysis.1 We evaluated how OCT parameters are interrelated and how they correlate with vision and other clinical features in idiopathic intracranial hypertension (IIH). Methods: 126 subjects in the IIH Treatment Trial (IIHTT) OCT substudy had Cirrus SD-OCT optic disc and macula scans analyzed using a 3-D segmentation algorithm to derive retinal nerve fiber layer (RNFL), total retinal thickness (TRT), retinal ganglion cell layer plus inner plexiform layer (GCL+IPL) thickness and ONH volume. SD- OCT parameter values were correlated with high and low contrast acuity, perimetric mean deviation (PMD), Frisén grading and IIH features. Results: At study entry, the average RNFL thickness, TRT, and ONH volume showed significant strong correlations (r > 0.90) with each other. The same OCT parameters showed a strong (r > 0.76) correlation with Frisén grade and a mild (r > 0.24), but significant correlation with lumbar puncture opening pressure. For all eyes at baseline, neither visual acuity (high or low contrast) nor mean deviation correlated with any OCT measure of swelling or GCL+IPL thickness. Conclusions: In newly diagnosed IIH, OCT demonstrated alterations of the peripapillary retina and ONH correlate with Frisén grading of papilledema. At presentation, OCT measures of papilledema, in patients with newly diagnosed IIH and mild vision loss, do not correlate with clinical features or visual dysfunction. Trial registration: clinicaltrials.gov identifier: NCT01003639.
- Baseline OCT Measurements in the Idiopathic Intracranial Hypertension Treatment Trial: Part I. Quality Control,Comparisons and Variability. [JOURNAL ARTICLE]
- Invest Ophthalmol Vis Sci 2014 Nov 4.
Purpose: Optical coherence tomography (OCT) has been utilized to investigate papilledema in single site, mostly retrospective studies. We investigated whether spectral domain OCT (SD-OCT), which provides thickness and volume measurements of the optic nerve and retina, could reliably demonstrate structural changes due to papilledema in a prospective multi-site clinical trial setting. Methods: At entry, 126 subjects in the Idiopathic Intracranial Hypertension Treatment Trial (IIHTT) with mild visual field loss had optic disc and macula scans using the Cirrus SD-OCT. Images were analyzed using the proprietary commercial and custom 3-D segmentation algorithms to calculate retinal nerve fiber layer (RNFL), total retinal thickness (TRT), optic nerve volume (ONHV), and retinal ganglion cell layer (GCL) thickness. We evaluated variability, inter-ocular comparison and correlation between results for both methods. Results: The average RNFL thickness was > 95% of normals in 90% of eyes and the RNFL, TRT, ONH height and ONHV showed strong (r > 0.8) correlations for interocular comparisons. Variability for repeated testing of OCT parameters was low for both methods and intraclass correlations were > 0.9 except for the proprietary GCL thickness. The proprietary algorithm derived RNFL, TRT, and GCL thickness measurements had failure rates of 10%, 16%, and 20% for all eyes respectively, which were uncommon with 3D-segmentation derived measurements. Only 7% of eyes had GCL thinning <5th percentile of normal age-matched control eyes by both methods. Conclusions: SD-OCT provides reliable continuous variables and quantified assessment of structural alterations due to papilledema. Trial registration: clinicaltrials.gov identifier: NCT01003639.
- Oscillatory potentials in electroretinogram as an early marker of visual abnormalities in vitamin A deficiency. [JOURNAL ARTICLE]
- Mol Med Rep 2014 Nov 3.
Vitamin A deficiency (VAD) caused by malnutrition and certain intestinal diseases induces visual impairments, including night blindness and photoreceptor cell dysfunction as indicated by reduced a‑ and b‑waves in an electroretinogram (ERG). The effects of VAD on the inner retinal layer cells, including amacrine and ganglion cells, remain to be elucidated. The functions of these cells are reflected in oscillatory potentials (OPs), another component of the ERG. The present study investigated inner retinal layer cell function in VAD rats by analyzing OPs. In the present study, VAD was induced by feeding Brown Norway rats a vitamin A deficient diet for 10 weeks. A reduced body weight and peri‑papillary opacification indicative of papilledema without histopathological alterations were observed, which are considered early symptoms of VAD. At this stage, the ERG revealed reduced OPs as well as a‑ and b‑waves at various intensities of light stimulation. Further analysis indicated that the ratio of the alterations in OPs was more significant than those of a‑ and b‑waves. After 5 weeks of recovery, these changes returned to control levels. These results suggest that OPs are the most sensitive and early marker of VAD‑associated visual impairment in the ERG.
- [Optic disc oedema.] [JOURNAL ARTICLE]
- Ugeskr Laeger 2014 May 19; 176(21)
Optic disc oedema describes the nonspecific, localized swelling of the optic nerve head regardless of aetiology. Therefore, differentiating among the various aetiologies depends on a thorough history and knowledge of the clinical characteristics of the underlying conditions. Papilloedema strictly refers to optic disc oedema as a consequence of elevated intracranial pressure. It is usually a bilateral condition and visual function is preserved until late. Optic disc oedema caused by an anterior optic neuropathy is usually unilateral and accompanied by the loss of visual function.
- Progressive Postnatal Pansynostosis. [JOURNAL ARTICLE]
- Cleft Palate Craniofac J 2014 Oct 28.
Objective : To describe the subtle clinical features, genetic considerations, and management of progressive postnatal pansynostosis, a rare form of multisutural craniosynostosis that insidiously occurs after birth and causes inconspicuous cranial changes. Design, Participants, Setting : The study is a retrospective chart review of all patients diagnosed with progressive postnatal pansynostosis at a major craniofacial center between 2000 and 2009. Patients with kleebattschädel were excluded. Results : Nineteen patients fit our inclusion criteria. Fifteen patients had a syndromic diagnosis: Crouzon syndrome (n = 8), Saethre-Chotzen syndrome (n = 5), and Pfeiffer syndrome (n = 2). With the exception of one patient with moderate turricephaly, all patients had a relatively normal head shape with cranial indices ranging from 0.72 to 0.93 (mean, 0.81). Patients were diagnosed at an average of 32.4 months; craniosynostosis was suspected based on declining percentile head circumference (n = 14), detection of an apical prominence (n = 12), papilledema (n = 7), and worsening exorbitism (n = 3). Nearly all patients had evidence of increased intracranial pressure. Conclusion : Progressive postnatal pansynostosis is insidious; diagnosis is typically delayed because the clinical signs are subtle and appear gradually. All infants or children with known or suspected craniosynostotic disorder and a normal head shape should be carefully monitored; computed tomography is indicated if there is any decrease in percentile head circumference or symptoms of intracranial pressure.