Chronic traumatic encephalopathy-a blueprint for the bridge between neurological and psychiatric disorders.

Chronic traumatic encephalopathy (CTE) is a perplexing condition characterized by a broad and diverse range of neuropathology and psychopathology. While there are no agreed upon or validated clinical criteria for CTE, case series of CTE have described a wide range of neuropsychiatric symptoms that have been attributed to repetitive traumatic brain injuries (rTBI). However, the direct links between the psychopathology of psychiatric and neurological conditions from rTBI to CTE remains poorly understood. Prior studies suggest that repetitive cerebral injuries are associated with damage to neural circuitry involved in emotional and memory processes, but these studies do not offer longitudinal assessments that prove causation. More recent studies on novel targets, such as transmission of misfolded proteins, as well as newly advanced non-invasive imaging techniques may offer more direct evidence of the pathogenesis of CTE by tracing the progression of pathology and display of related behavioral impairments. Understanding this interface in the context of rTBI can play an important role in future approaches to the definition, assessment, prevention, and treatment of CTE and mental illnesses.

Acquired Chiari I Malformation Secondary to Spontaneous Intracranial Hypotension Syndrome and Persistent Hypoglycemia: A Case Report

Spontaneous intracranial hypotension (SIH) is a rare and potentially serious condition in childhood. Cerebrospinal fluid (CSF) volume depletion is thought to be the main causative feature for intracranial hypotension and results from a spontaneous CSF leak, often at the spine level. SIH is increasingly diagnosed in clinical practice, although it manifests a varied symptomatology. The downward displacement of the brain, sometimes mimicking a Chiari I malformation, has rarely been reported. We present a case of a SIH with Chiari I malformation accompanied by an unusual clinical presentation of persistent hypoglycemia.

Frequency of Nerve Root Sleeve Cysts in Autosomal Dominant Polycystic Kidney Disease.

BACKGROUND: There is sporadic data about the occurrence of spinal meningeal cysts in patients with autosomal dominant polycystic kidney disease (ADPKD). We suggest that there is a relationship with the frequency and size of spinal meningeal cysts and headache, intracranial aneurysms, and cerebrospinal fluid leakage in patients with ADPKD. AIM: To investigate the relationship with spinal meningeal cyst, cerebrospinal fluid leakage, and headache in patients with ADPKD. STUDY DESIGN: Cross-sectional study. METHODS: We enrolled 50 patients with ADPKD and 37 healthy volunteers. This cross-sectional study included patients with ADPKD and matched healthy volunteers. Magnetic resonance imaging myelography was performed using the 3D-T2 HASTE technique in an MRI scanner. We questioned our subjects regarding presence of headache and evaluated headache severity using a visual analog scale. The relationship between the number and size of spinal meningeal cysts with headache, intracranial aneurysms, and liver cysts was also investigated. RESULTS: Spinal meningeal cysts were more numerous and larger in patients than in controls (14.8±11.6 vs. 6.4±4.6 cysts respectively, p<0.001, 68.3±49.3 vs. 25.4±20.1 mm, p<0.001, respectively). Spinal cyst number and size were similar in APDKD patients with or without intracranial aneurysms. Headache score was correlated with the size and number of spinal meningeal cysts. This was valid only in patients with ADPKD. CONCLUSION: Abnormality involving the vessel wall in ADPKD may explain the increased number of spinal meningeal cysts in ADPKD. Moreover, leakage of cerebrospinal fluid secondary to spinal meningeal cyst may be responsible for recurrent severe headache by causing spontaneous intracranial hypotension in these patients.

Spontaneous intracranial hypotension presenting with coma: a case report and literature review.

Spontaneous intracranial hypotension is characterized by orthostatic headache in the absence of a history of head trauma or lumbar puncture, and diagnosis is confirmed by a specific cerebrospinal fluid pressure and neuroimaging findings. It rarely presents with coma. A 62-year-old man presented with progressive cognitive decline of 2 to 4 weeks' duration. He was diagnosed with spontaneous intracranial hypotension according to cerebrospinal fluid pressure and neuroimaging findings, and treated conservatively.

Contribution of FDG-PET in epilepsy surgery: consistency and postoperative results compared with magnetic resonance imaging and electroencephalography.

AIM: Surgery is a treatment option for medically intractable epilepsy patients. Abnormalities in regional cerebral glucose metabolism, as identified by 18-fluorodeoxyglucose positron emission tomography (FDG-PET) have predictive prognostic value in evaluating the outcome of epilepsy surgery. This study investigated the efficacy of FDG-PET for delineation of the epileptogenic zone (EZ) by comparing its consistency with other diagnostic tools and surgical outcome. MATERIAL AND METHODS: We analyzed the results of 121 consecutive patients evaluated for epilepsy surgery. FDG-PET results were crosschecked with magnetic resonance imaging (MRI) and electroencephalography (EEG) results, as well as postoperative outcome and pathology. RESULTS: FDG-PET findings of 75 patients (62 %) were concordant with MRI (Mc-Nemar-χ2 test p=0.024, Kappa=0.22). Further, the PET findings were consistent with EEG, and was statistically significant, according to Post-hoc test, in temporal epilepsy (TLE) group (χ2=8.21 P=0.04). Both investigations revealed localizing information in 56 (46.2%) patients. Twenty-six (72.2%) MRI-negative patients had hypometabolism on PET. The pathology of the 10 PET-negative patients was 5 cases of mesial temporal sclerosis, 2 cortical dysplasia, 2 gliosis and one tumor. Seven (70%) of these patients' lesions originated from the temporal lobe. FDG-PET had correctly predicted the EZ in 37 (86%) of 43 patients who underwent surgery. CONCLUSION: FDG-PET results may not be strongly associated with EZ but represent an additional tool in delineation of EZ during the noninvasive phase of presurgical evaluation.

Osteointegration of a bisphenol-a-glycidyl-dimethacrylate composite and its use in anterior skull base defects: an experimental study in an experimental design model of cerebrospinal fluid leak.

OBJECT: Promising clinical results were reported in watertight closure of anterior skull base defects (ASBDs) with bisphenol-a-glycidyl-dimethacrylate (bis-GMA)-based materials to prevent the cerebrospinal fluid leaks. However, interrelation of these materials with surrounding bones in histologic level, referred to as the osteointegration, has not been reported in the anterior skull base. In addition, an illustrative case with an ASBD that was repaired using a bis-GMA composite has been presented. METHODS: Twenty New Zealand rabbits were divided into 4 groups: control and sham groups consisted of 2 and 6 rabbits, respectively. The "skull base defect" group (n = 6) underwent a unifrontal craniectomy and an iatrogenic ASBD followed by creating a dural defect to obtain a cerebrospinal fluid leak. Similar bony and dural defects were acquired in the "repair with bis-GMA based allograft" group (n = 6), but the bony defect was closed with bis-GMA-based allograft. RESULTS: All animals in the "skull base defect" group died in 3 weeks after surgery. There were no animal losses in the "repair with bis-GMA based allograft" group at the sixth month. Histologic evaluation revealed complete osteointegration of bis-GMA composite with surrounding bones. CONCLUSIONS: bis-GMA based allograft achieved a watertight repair of the ASBD. Histologic findings of this study showed that bis-GMA composite is a reliable material to be used in the closure of anterior skull base bony defects.

Can Ramadan fasting cause relapse and aggravation of spontaneous intracranial hypotension?

Chronic headache is known to be aggravated by fasting and fasting even triggers headache among those not suffering from chronic headache. Headache is also aggravated during Ramadan in which Muslim people do not eat, drink, or smoke from dawn to sunset for about one month in a year. Headaches mainly increase in people who are prone to headaches like migraine sufferers. As far as we know there are no reports on specific headache syndromes pointing to precipitating factor of fasting. In this report, we present a 32-year-old man diagnosed with spontaneous intracranial hypotension, treated by conservative means and who relapsed after fasting during Ramadan. We aim to discuss the possible underlying mechanisms of precipitation of orthostatic headache during fasting.

Cavernous hemangioma of the cavernous sinus misdiagnosed as a meningioma: a case report and MR imaging findings.

Cavernous hemangioma (CH) is a benign vascular malformation. Intracranial CH is generally localized as an intracranial-intraaxial and responsible for 5-13% of all intracranial vascular malformations. Intracranial-extraaxial CHs are rare rather than intracranial-intraaxial CHs. Clinical findings, imaging characteristics, and surgical approach of extraaxial CHs are rather different than intraaxial CHs. Diagnosing cavernous sinus CH preoperatively is very important, but its radiological differential diagnosis is quite difficult. In this study, we present magnetic resonance imaging findings of a 48-year-old male who was considered preoperatively to have meningioma but was diagnosed with cavernous sinus CH during surgery by pathological examination.

Anastomoses of the vestibular, cochlear, and facial nerves.

The internal auditory canal (IAC) is 10 to 17 mm in length, and the facial nerve and vestibulocochlear nerve, which consist of the cochlear nerve, the superior vestibular nerve, and the inferior vestibular nerve, run together in the IAC packaged in dura mater. Oort first described the vestibulocochlear anastomoses in 1918, which is important for the understanding of the pathogenesis and pathophysiology of otologic disorders. The current study documents the existence of vestibulofacial and vestibulocochlear neural connections and topographical relationship of the nerves as part of a radiologic evaluation of 73 human temporal bones from brainstem to the lateral portion of IAC.

Assessment of CSF flow dynamics using PC-MRI in spontaneous intracranial hypotension.

AIM: Spontaneous intracranial hypotension (SIH) is caused by spontaneous cerebrospinal fluid (CSF) leaks and is known to cause orthostatic headaches. Phase-contrast magnetic resonance imaging (PC-MRI) is a non-invasive technique that can be used to quantify variation in CSF flow. The aim of this study was to assess CSF flow dynamics using PC-MRI in SIH. MATERIALS AND METHODS: Twenty-five patients with a definitive diagnosis of SIH and 25 healthy subjects were evaluated with PC-MRI. Magnetic resonance (MR) images were acquired using a 1.5-T unit with an 8-channel head coil. Differences between SIH patients and control subjects were assessed statistically using Wilcoxon's rank sum test, Spearman's rho test, or Pearson's chi-square test, as appropriate. RESULTS: CSF flow volumes toward the third ventricle, CSF flow volumes toward the fourth ventricle, the absolute stroke volume, the peak systolic velocity, and the peak diastolic velocity in SIH patients were significantly smaller than those in control subjects (P < .0001). On the other hand, the net CSF flow volume (P = .9227) and the net CSF flow direction (P = .2472) for SIH patients and control subjects were not significantly different. CONCLUSIONS: The results obtained by CSF flow analysis were directly related to values of CSF opening pressure, determined by lumbar puncture, and clinical findings, such as headache scores. Thus, CSF flow analysis with PC-MRI, which has a short performance time and is non-invasive, may contribute to assessment of SIH patients.

Spontaneous intracranial hypotension syndrome may mimic aseptic meningitis.

BACKGROUND: Spontaneous intracranial hypotension (SIH) is recognized with increasing frequency. A throbbing headache occurring or worsening in the upright position and improving after lying down, a so-called 'orthostatic headache', low cerebrospinal fluid (CSF) pressure, and diffuse pachymeningeal enhancement on brain magnetic resonance imaging (MRI) are the major features of the classic syndrome. These patients, who are admitted with fever, headache, and CSF findings revealing lymphocytic pleocytosis, elevated protein concentration, normal glucose levels, and negative culture results, are prone to be misdiagnosed with aseptic meningitis. The aims of this single-centre retrospective study were to determine the epidemiological, clinical, laboratory, and radiological features of patients initially evaluated as having aseptic meningitis but subsequently diagnosed with SIH, and to touch upon the key points of the differential diagnosis in daily infectious diseases practice. METHODS: Patients referred to Cerrahpasa Medical School with a presumed diagnosis of aseptic meningitis or viral meningitis between 1 January 2006 and 1 January 2011 were reviewed. Epidemiological, clinical, laboratory, radiological, and follow-up data obtained from the hospital database were processed. Patients confirmed to have SIH syndrome were included for evaluation. RESULTS: Eleven cases of SIH syndrome were diagnosed during the study period (8 male and 3 female, median age 30 y, range 21-44 y). All had headache, hearing changes, and nausea. Vomiting (10/11) and posterior neck pain (9/11) were also frequent. Seven had fever and 5 had a stiff neck. Four cases had lymphocytic pleocytosis, 4 cases had elevated CSF protein concentrations (> 1.5 times the upper limit of normal), and 2 cases had slightly lower CSF glucose levels. Polymerase chain reaction (PCR) analyses of the CSF for Mycobacterium tuberculosis complex, herpes simplex viruses 1 and 2, and enteroviruses were negative in all cases. MRI of the 11 cases revealed signs of spontaneous CSF leaks with diffuse pachymeningeal gadolinium enhancement (11/11), sagging of the brain (9/11), enlargement of the pituitary (6/11), engorgement of the venous structures (5/11), and subdural fluid collections (2/11). CSF leaks were demonstrated by intrathecal magnetic resonance or computed tomography myelography at different levels along the thoracic spine (7/11), cervico-thoracic junction (2/11), and thoraco-lumbar junction (2/11). Autologous blood injection into the spinal epidural space ('blood patch') was performed for treatment. Strict bed rest followed, and all patients recovered fully within a week; no recurrence or complication was observed during the follow-up periods, which ranged from 6 months to 5 y. CONCLUSIONS: Findings of fever, headache, and meningeal irritation are generally accepted as the clinical features of meningitis. When CSF findings are not characteristically compatible with bacterial meningitis and particularly when the headache is orthostatic in nature, SIH should also be included in the differential diagnosis. MRI findings are characteristic and clearly contribute to the differential diagnosis between viral meningitis and SIH.

Direct venous spinal reabsorption of cerebrospinal fluid: a new concept with serial magnetic resonance cisternography in rabbits.

OBJECT: For nearly 100 years it has been believed that the main reabsorption of CSF occurs in arachnoid projections into the superior sagittal sinus, but a significant number of experiments and cases conflict with this hypothesis. According to recently published studies, CSF is permanently produced and absorbed in the whole CSF system. Clusters of arachnoidal villi, which are speculated to have a role in the reabsorption of CSF, have recently been revealed in the dorsal root of the spinal nerves. Huge absorptive surface areas of microvessels have been suggested to serve a putative role in reabsorption. The authors' aim was to observe direct venous connections between the subarachnoid space and the perispinal veins. METHODS: Eleven adult (6 months old) New Zealand white male rabbits weighing approximately 3.0 kg each were used in this experiment. After obtaining precontrast MR cisternography images, subarachnoid access was gained percutaneously via a cisternal approach by using a 20-gauge intravenous indwelling cannula. One rabbit died as a result of brainstem trauma during percutaneous cannulation before contrast administration, but contrast agent was still injected to see the possible MR imaging results of spinal CSF reabsorption after death. Magnetic resonance imaging was performed at 15, 60, 120, and 180 minutes after the administration of contrast agent. After intramuscular injections of anesthetic, 2 rabbits died 120 and 150 minutes after contrast injection, but the MR imaging study at 180 minutes after contrast injection was still performed. RESULTS: Direct connections between the subarachnoid space and the perispinal veins were observed in all rabbits during serial MR cisternography. The enhancement power was not affected by the amount of injected contrast agent or by cervical or lumbar penetration but was increased at higher contrast concentrations or upon seizure (physical activity). CONCLUSIONS: Extracranial reabsorption of CSF has been finally proved with direct radiological confirmation of spinal venous reabsorption of CSF using serial MR cisternography. The authors believe that this study can help to develop a more accurate model of CSF dynamics, which will allow understanding of many CSF-related diseases, as well as the development of new strategies for treatment.

A Radiological Study on the Topographical Relationships between the Vestibular, Cochlear and Facial Nerves.

OBJECTIVE: The purpose of our study was to investigate the topographical relationship between these nerves along their course from the brainstem through the internal acoustic canal IAC in the living human brain using MR imaging. MATERIALS AND METHODS: We performed three-dimensional gradient echo balanced Fast Field Echo (3D bFFE) sequence oblique parasagittal MR imaging in 73 healthy subjects. The IACs were analyzed from the brainstem end of the IAC to the fundus in contiguous sections. At five levels, the topographical relationships between the facial and vestibulocochlear nerves (VCN) were recorded. In the lateral portions of the IACs where they separated from each other, the relative sizes of the individual nerves were examined. RESULTS: In general, the facial nerve (FN), which is a round structure, is located anteriorly and superiorly to the vestibulocochlear nerve throughout its course. The vestibulocochlear nerve is usually rectangular; however, it was found to be round and at times triangular in shape near the brainstem, before it became crescent-shaped at the porus in 89% of the cases. The superior vestibular nerve kept its posterosuperior position in the canal, and the inferior vestibular nerve (IVN) and the cochlear nerve (CN) travelled inferior to it. The superior and inferior vestibular nerves were divided by the falciform crest in 53% of the cases. The inferior vestibular nerve was the smallest nerve in 52% of the cases, and the cochlear nerve was the largest in 36% of the cases. CONCLUSION: To the best of our knowledge, this study is the largest in vivo MR study, and most of our findings differ from previous cadaver studies. Determination of these topographical relationships may facilitate our understanding of the complicated physiological relationships between the 7(th) and 8(th) nerve complexes during surgery in this region.

Diffusion-weighted imaging findings in brain death.

INTRODUCTION: The purpose of the present study was to determine the role of diffusion-weighted imaging (DWI) and to investigate the use of DWI in the diagnosis of brain death (BD). METHODS: We prospectively evaluated 22 patients diagnosed with clinical BD (9 women, 13 men; mean age, 39.63 ± 15.1 years; age range, 9-66 years). All clinical criteria for BD were present in all 22 patients before magnetic resonance imaging, including a positive apnea test. For all cases, DW images, T2-weighted images, and fluid-attenuated inversion recovery were obtained. Thirteen distinct neuroanatomical structures were selected for analysis in all the cases. For each region of interest, the mean, standard deviation, and range of the average apparent diffusion coefficient (ADCav) values were obtained. RESULTS: For BD patients, ADC values in all neuroanatomical structures were significantly lower than those for control subjects. We determined how ADC values in all structures were related to the diagnostic condition as well as the appropriate threshold ADC values to classify a subject as BD or control. The sensitivity, specificity, positive and negative predictive values, and correct classification rate of ADC cutoff values to distinguish BD from control groups were 100%. CONCLUSIONS: DWI might be used as a noninvasive confirmatory test for the diagnosis of BD in the future.

A case of primary Sjögren's syndrome presenting primarily with central nervous system vasculitic involvement.

Sjögren's syndrome is primarily a chronic systemic autoimmune disease that affects exocrine organs. Neurologic symptoms frequently present as peripheral neuropathy due to small vessel vasculitis. Type and prevalence of central nervous system involvement are still controversial. In this report, we present a 35-year-old woman with primary Sjögren's syndrome with central nervous system vasculitic involvement.

CT-guided percutaneous translaminar approach for blood patching: case report and technical note.

In this article the authors describe a novel technique for performing epidural blood patch (EBP) by percutaneous CT-guided translaminar approach in challenging cases where interlaminar approach is not possible. A 24-year-old woman with medical history of multiple spinal surgeries and instrumentations for the treatment of scoliosis, presented 3 months post-operatively with acute and severe orthostatic headaches that began 1 week after surgery. Neurological examination was normal. Brain magnetic resonance imaging (MRI) showed mild thickening and contrast enhancing in the bilateral dura. Computed tomography (CT) myelography revealed CSF leakage in the level of T3 vertebra. EBP was attempted using fluoroscopic and then CT guidance; however, despite multiple attempts, the epidural space could not be accessed through the interlaminar route due to extensive instrumentation of the spine and profound structural bony abnormalities. EBP was performed successfully via a CT-guided translaminar approach using an Ostycut trephine needle (Angiomed(®)/Bard, Karlsruhe), without complications.

Spontaneous intracranial hypotension due to intradural thoracic osteophyte with superimposed disc herniation: report of two cases.

Spontaneous intracranial hypotension (SIH) is a clinical syndrome in which absolute or relative hypovolemia of the cerebrospinal fluid (CSF) results in various neurological symptoms. The etiology of spontaneous CSF leaks often remains unknown. However, it is believed that the most common cause is the fragility of spinal meninges at the level of radicular nerve root sleeve. These tears can be spontaneous (primary) or secondary. Spinal pathologies can cause this tear with resultant CSF leak and SIH, which include spinal trauma, degenerative diseases and spinal surgery. Uncommonly, SIH is developed by osteophyte with disc herniation without any other pathology. In this article, we reported two cases of SIH secondary to spinal dural tear due to intradural thoracic osteophyte with superimposed disc herniation, with the absence of other pathologies, which were treated successfully with epidural blood patch (EBP).

Magnetic resonance imaging of rheumatoid meningitis: a case report and literature review.

Rheumatoid meningitis is a rare and serious complication of rheumatoid arthritis (RA) with high mortality rate. Clinical importance of the disease is high because diagnosis is difficult, and the disease is treatable if diagnosed successfully. We present the clinical and cranial magnetic resonance imaging findings of 62-year-old female patient with RA who has been followed up for 4 years.