Thoracic arachnoid cyst resection.
Arachnoid cysts in the spinal cord may be asymptomatic. In some cases arachnoid cysts may exert mass effect on the thoracic spinal cord and lead to pain and myelopathy symptoms. Arachnoid cysts may be difficult to visualize on an MRI scan because the thin walled arachnoid may not be visible. Focal displacement of the thoracic spinal cord and effacement of the spinal cord with apparent widening of the cerebrospinal fluid space is seen. This video demonstrates surgical techniques to remove a dorsal arachnoid cyst causing spinal cord compression. The surgery involves a thoracic laminectomy. The dura is opened sharply with care taken not to open the arachnoid so that the cyst can be well visualized. The thickened arachnoid walls of the cyst are removed to alleviate the compression caused by the arachnoid cyst. The video can be found here: http://youtu.be/pgUrl9xvsD0.
McCormick, Paul C
Dorsal thoracic arachnoid web is a rare but often overlooked cause of progressive myelopathy. Syringomyelia, either above or below the compressive arachnoid band, may also be present. Dorsal arachnoid cyst and ventral spinal cord herniation may be mistaken for this condition. This video demonstrates the microsurgical identification and techniques of resection of a dorsal arachnoid band producing a progressive myelopathy in a 63-year-old man. The video can be found here: http://youtu.be/KDNTqiyW6yo.
NASA Astrophysics Data System (ADS)
Kostama, V.-P.; Tormanen, T.
The Venusian volcano-tectonic structures have been subject to many classification and characterisation schemes. Several structure-types have been identified (e.g. coronae, novae, arachnoids, calderas, and corona-novae). Of these groups, the relationship of arachnoids and coronae has been complicated, and is a subject to much debate. Some previous works and studies have fused these two categories together, and even promoted the view of non-existence of arachnoids at times. However, based on the recognisable differences in morphology and other characteristics (e.g. size, topography, volcanism), they should be treated as a separate class of structures. In our first global study of the volcano-tectonic features, we found 96 arachnoids [1, 2]. During the reanalysis of the features as a by-product of another study, the arachnoid population was re-evalueted, and more importantly, the identification criteria was rechecked. The revised population increases the arachnoid number to 130 features. The work also produced many examples of features that can be considered as transitional forms between different morphological groups.  Kostama, V.-P., M. Aittola, LPSC XXXII, Abstract#1185, 2001a.  Kostama, V.-P., M. Aittola, The Catalogue of Venusian Arachnoids, Coronae and Novae, http://cc.oulu.fi/tati/JR/Venus/volcanotectonics/catalogue.html, 2001b.
Characteristics of arachnoids from Magellan data
NASA Technical Reports Server (NTRS)
Dawson, C. B.; Crumpler, L. S.
Current high resolution Magellan data enables more detailed geological study of arachnoids, first identified by Barsukov et al. as features characterized by a combination of radar-bright, concentric rings and radiating lineations, named 'arachnoids' on the basis of their spider and web-like appearance. Identification of arachnoids in Magellan data has been based on SAR images, in keeping with the original definition. However, there is some overlap by other workers in identification of arachnoids, corona (predominantly bright rings), and novae (predominantly radiating lineations), as all of these features share some common characteristics. Features used in this survey were chosen based on their classification as arachnoids in Head et al.'s catalog and on SAR characteristics matching Barsukov et al.'s original definition. The 259 arachnoids have been currently identified on Venus, all of which were considered in this study. Fifteen arachnoids from different regions, chosen for their 'type' characteristics and lack of deformation by other regional processes, were studied in depth, using SAR and altimetric data to map and profile these arachnoids in an attempt to better determine their geologic and altimetric characteristics and possible formation sequences.
[Arachnoid cysts: Embriology and pathology].
García-Conde, Mario; Martín-Viota, Lucia
There is still great controversy surrounding the origin of the arachnoid cyst. The most accepted theory in the case of congenital cysts explains how they are formed from an anomalous development of the arachnoid membrane, which is unfolded allowing the accumulation of cerebrospinal fluid inside and creating a cyst. This theory seems to explain the origin of convexity and sylvian cistern arachnoid cysts, whereas those in other locations might be due to other mechanisms. In the anatomopathological analysis, the arachnoid cyst wall can be seen as having few differences from normal, although thickened due to an increase quantity of collagenous material. A description of the embryological development of the arachnoid layer and cyst formation is presented, describing the main anatomopathological findings. Copyright © 2015 Sociedad Española de Neurocirugía. Published by Elsevier España. All rights reserved.
Arachnoiditis ossificans of the thoracic spine.
Bagley, Jacob H; Owens, T Ryan; Grunch, Betsy H; Moreno, Jessica R; Bagley, Carlos A
Arachnoiditis ossificans is a rare disorder characterized by the development of calcifications of the arachnoid membrane of the thoracic and lumbar spines. It is an extremely rare cause of spinal canal stenosis and consequent neurological compromise, and its origins and optimal management remain unclear. We review of the literature that illustrates the challenges of diagnosis and treatment of arachnoiditis ossificans. A patient with arachnoiditis ossificans is discussed to illustrate the presentation, treatment, and prognosis of the disease. Copyright © 2013 Elsevier Ltd. All rights reserved.
[Rare location of arachnoid cysts. Extratemporal cysts].
Martinez-Perez, Rafael; Hinojosa, José; Pascual, Beatriz; Panaderos, Teresa; Welter, Diego; Muñoz, María J
The therapeutic management of arachnoid cysts depends largely on its location. Almost 50% of arachnoid cysts are located in the temporal fossa-Sylvian fissure, whereas the other half is distributed in different locations, sometimes exceptional. Under the name of infrequent location arachnoid cysts, a description is presented of those composed of 2 sheets of arachnoid membrane, which are not located in the temporal fossa, and are primary or congenital. Copyright © 2015 Sociedad Española de Neurocirugía. Published by Elsevier España. All rights reserved.
Arachnoid membranes in the posterior half of the incisural space: an inverted Liliequist membrane-like arachnoid complex.
Zhang, Xi-An; Qi, Song-Tao; Fan, Jun; Huang, Guang-Long; Peng, Jun-Xiang
The aim of this study was to describe the similarity of configuration between the arachnoid complex in the posterior half of the incisural space and the Liliequist membrane. Microsurgical dissection and anatomical observation were performed in 20 formalin-fixed adult cadaver heads. The origin, distribution, and configuration of the arachnoid membranes and their relationships with the vascular structures in the posterior half of the incisural space were examined. The posterior perimesencephalic membrane and the cerebellar precentral membrane have a common origin at the tentorial edge and form an arachnoid complex strikingly resembling an inverted Liliequist membrane. Asymmetry between sides is not uncommon. If the cerebellar precentral membrane is hypoplastic on one side or both, the well-developed quadrigeminal membrane plays a prominent part in partitioning the subarachnoid space in the posterior half of the incisural space. The arachnoid complex in the posterior half of the incisural space can be regarded as an inverted Liliequist membrane. This concept can help neurosurgeons to gain better understanding of the surgical anatomy at the level of the tentorial incisura.
Dissapearance of arachnoid cyst after rupturing into subdural space.
Yilmaz, C; Cetinalp, E; Caner, H; Altinors, N
Arachnoid cysts are developmental anomalies usually diagnosed in childhood. The most important complications of arachnoid cysts are subdural haematomas and hygromas and intracystic haemorrhage. In our case we present a 7-year-old boy whose arachnoid cyst ruptured into the subdural space following a mild head injury and disappeared after draining the subdural haematoma by burr-holes.
Arachnoid cyst with rupture into the subdural space.
Cullis, P A; Gilroy, J
Arachnoid cysts which develop in relation to the cerebral hemispheres are usually found in the middle cranial fossa. These cysts are usually asymptomatic but can produce symptoms if there is haemorrhage into the cyst or the development of an associated subdural hematoma. Recent publications have emphasised the association of arachnoid cysts of the middle fossa with subdural haematomas. This report describes a case of an asymptomatic arachnoid cyst which ruptured into the subdural space. This event was followed by the development of symptoms despite the lack of haemorrhage. Images PMID:6101185
Risk factors for pediatric arachnoid cyst rupture/hemorrhage: a case-control study.
Cress, Marshall; Kestle, John R W; Holubkov, Richard; Riva-Cambrin, Jay
As the availability of imaging modalities has increased, the finding of arachnoid cysts has become common. Accurate patient counseling regarding physical activity or risk factors for cyst rupture or hemorrhage has been hampered by the lack of definitive association studies. This case-control study evaluated factors that are associated with arachnoid cyst rupture (intracystic hemorrhage, adjacent subdural hematoma, or adjacent subdural hygroma) in pediatric patients with previously asymptomatic arachnoid cysts. Patients with arachnoid cysts and intracystic hemorrhage, adjacent subdural hygroma, or adjacent subdural hematoma treated at a single institution from 2005 to 2010 were retrospectively identified. Two unruptured/nonhemorrhagic controls were matched to each case based on patient age, sex, anatomical cyst location, and side. Risk factors evaluated included arachnoid cyst size, recent history of head trauma, and altitude at residence. The proportion of imaged arachnoid cysts that presented either originally or subsequently with a rupture or hemorrhage was 6.0%. Larger cyst size, as defined by maximal cyst diameter, was significantly associated with cyst rupture/hemorrhage (P < .001). When dichotomized with a 5-cm cutoff, 9/13 larger cysts ruptured and/or hemorrhaged, whereas only 5/29 smaller cysts ruptured/hemorrhaged (odds ratio = 16.5 (confidence interval [2.5, ∞]). A recent history of head trauma was also significantly associated with the outcome (P < .001; odds ratio = 25.1 (confidence interval [4.0, ∞]). Altitude was not associated with arachnoid cyst rupture or hemorrhage. This case-control study suggests that larger arachnoid cyst size and recent head trauma are risk factors for symptomatic arachnoid cyst rupture/hemorrhage.
Intraoperative Visualization of a Spinal Arachnoid Cyst Using Pyoktanin Blue.
Takamiya, Soichiro; Seki, Toshitaka; Yamazaki, Kazuyoshi; Sasamori, Toru; Houkin, Kiyohiro
Spinal arachnoid cysts (SACs) are filled with cerebrospinal fluid, and they include the arachnoid membrane, making it difficult to distinguish the walls of the cyst from the arachnoid membrane and excise the cyst as a lump. Here we report a technique for the intraoperative visualization of SACs, involving the use of pyoktanin blue. Four patients with spinal intradural arachnoid cysts underwent total excision of the cysts between October 2016 and April 2017. In 1 case, magnetic resonance imaging revealed the cyst clearly, but in the other cases, the cysts were unclear. All cysts were injected with 1% pyoktanin blue (Wako Pure Chemical Industries, Osaka, Japan) diluted 500 times with physiological saline before excision. When it was difficult to distinguish the cyst from the normal arachnoid membrane, 1% pyoktanin blue diluted 1000 times with physiological saline was injected into both the cyst and the subarachnoid space, and the spread of the stain was observed. The cysts were better visualized after pyoktanin blue injection than before injection. When it was difficult to distinguish the cyst from the normal arachnoid space, pyoktanin blue injection was useful for judging the cyst space. There were no perioperative complications, and the patients' symptoms improved partially or completely after treatment. Our technique of pyoktanin blue injection into SACs could make their excision easy and safe. Copyright © 2017 Elsevier Inc. All rights reserved.
Spontaneous disappearance of two asymptomatic arachnoid cysts in two different locations.
Cokluk, C; Senel, A; Celik, F; Ergür, H
We report two children with asymptomatic arachnoid cysts which resolved spontaneously without any surgical intervention and history of major head and body trauma. The first child was a 10-year-old boy with an arachnoid cyst in the right sylvian fissure. The second child was a 1-year-old girl with a right cerebral convexity arachnoid cyst. Both of them were asymptomatic. Arachnoid cysts spontaneously disappeared within 2 years following initial diagnosing. There was no major head and body trauma except usual home, school and sports activity. We speculated that the cysts ruptured into cerebrospinal fluid circulation by the mechanical effects of some forced activities to the brain tissue and cyst, such as excessive breathing, coughing and sport activities. These factors may change the balance between intracystic and pericystic pressure and facilitate the rupturing of the cyst into subdural, subarachnoid and intraventricular spaces. These cases demonstrate that neurosurgical intervention of asymptomatic arachnoid cysts is not absolutely indicated in the paediatric age group. Close follow up with computerized tomography (CT) and magnetic resonance imaging (MRI) is a treatment option in the patient with arachnoid cysts located in the middle cranial fossa and cerebral convexity.
Intracranial aneurysm and arachnoid cyst: just a coincidence? A case report.
Aguiar, Guilherme Brasileiro de; Santos, Rafael Gomes Dos; Paiva, Aline Lariessy Campos; Silva, João Miguel de Almeida; Silva, Rafael Carlos da; Veiga, José Carlos Esteves
Presence of an arachnoid cyst and a non-ruptured intracystic brain aneurysm is extremely rare. The aim of this paper was to describe a case of a patient with an arachnoid cyst and a non-ruptured aneurysm inside it. Clinical, surgical and radiological data were analyzed and the literature was reviewed. A patient complained of chronic headache. She was diagnosed as having a temporal arachnoid cyst and a non-ruptured middle cerebral artery aneurysm inside it. Surgery was performed to clip the aneurysm and fenestrate the cyst. This report raises awareness about the importance of intracranial vascular investigation in patients with arachnoid cysts and brain hemorrhage.
The effects of blood and blood products on the arachnoid cell.
Hansen, Eric A; Romanova, Liudmila; Janson, Christopher; Lam, Cornelius H
After traumatic brain injury (TBI), large amounts of red blood cells and hemolytic products are deposited intracranially creating debris in the cerebrospinal fluid (CSF). This debris, which includes heme and bilirubin, is cleared via the arachnoid granulations and lymphatic systems. However, the mechanisms by which erythrocytes and their breakdown products interfere with normal CSF dynamics remain poorly defined. The purpose of this study was to model in vitro how blood breakdown products affect arachnoid cells at the CSF-blood barrier, and the extent to which the resorption of CSF into the venous drainage system is mechanically impaired following TBI. Arachnoid cells were grown to confluency on permeable membranes. Rates of growth and apoptosis were measured in the presence of blood and lysed blood, changes in transepithelial electrical resistance (TEER) was measured in the presence of blood and hemoglobin, and small molecule permeability was determined in the presence of blood, lysed blood, bilirubin, and biliverdin. These results were directly compared with an established rat brain endothelial cell line (RBEC4) co-cultured with rat brain astrocytes. We found that arachnoid cells grown in the presence of whole or lysed erythrocytes had significantly slower growth rates than controls. Bilirubin and biliverdin, despite their low solubilities, altered the paracellular transport of arachnoid cells more than the acute blood breakdown components of whole and lysed blood. Mannitol permeability was up to four times higher in biliverdin treatments than controls, and arachnoid membranes demonstrated significantly decreased small molecule permeabilities in the presence of whole and lysed blood. We conclude that short-term (<24 h) arachnoid cell transport and long-term (>5 days) arachnoid cell viability are affected by blood and blood breakdown products, with important consequences for CSF flow and blood clearance after TBI.
Surgically treated de novo cervico-medullary arachnoid cyst in a symptomatic adult patient.
Clifton, William; Rahmathulla, Gazanfar; Tavanaiepour, Kourosh; Alcindor, Dunbar; Jakubek, George; Tavanaiepour, Daryoush
Arachnoid cysts are a relatively common finding in adult patients, especially with the advent of advanced imaging techniques. The overall incidence ranges from 1-2%, and the majority are clinically silent 1,2 . Arachnoid cysts are postulated to arise by congenital anomalies or trauma 1 . De novo formation of arachnoid cysts has been reported, but is exceptionally rare and mostly found in the pediatric population after head trauma 3-5 . There have only been two reported cases of symptomatic de novo arachnoid cyst formation in adult patients to date, both with histories of head trauma 6,7 . We present a case of a 71-year-old male patient with progressive vertigo who had previous brain MRI studies without abnormalities. Another MRI was performed three years from the last study that showed interval development of a large cystic lesion compressing the right cervicomedullary junction, as well as radiologic evidence of neurosarcoidosis. Intraoperative findings showed a cystic mass with clear, gelatinous fluid. The cyst was drained and the walls were resected and sent to pathology. Histopathologic testing confirmed the lesion was an arachnoid cyst. The patient's vertiginous symptoms improved after surgery. This case represents the first incidence of a pathology proven, non-traumatic de novo arachnoid cyst. Copyright © 2018 Elsevier Inc. All rights reserved.
Arachnoid cyst in a patient with psychosis: Case report
da Silva, Joaquim Alves; Alves, Alexandra; Talina, Miguel; Carreiro, Susana; Guimarães, João; Xavier, Miguel
Background The aetiology of a psychotic disturbance can be due to a functional or organic condition. Organic aetiologies are diverse and encompass organ failures, infections, nutritional deficiencies and space-occupying lesions. Arachnoid cysts are rare, benign space-occupying lesions formed by an arachnoid membrane containing cerebrospinal fluid (CSF). In most cases they are diagnosed by accident. Until recently, the coexistence of arachnoid cysts with psychiatric disturbances had not been closely covered in the literature. However, the appearance of some references that focus on a possible link between arachnoid cysts and psychotic symptoms has increased the interest in this subject and raised questions about the etiopathogeny and the therapeutic approach involved. Clinical presentation We present the clinical report of a 21-year-old man, characterised by the insidious development of psychotic symptoms of varying intensity, delusional ideas with hypochondriac content, complex auditory/verbal hallucinations in the second and third persons, and aggressive behaviour. The neuroimaging studies revealed a voluminous arachnoid cyst at the level of the left sylvian fissure, with a marked mass effect on the left temporal and frontal lobes and the left lateral ventricle, as well as evidence of hypoplasia of the left temporal lobe. Despite the symptoms and the size of the cyst, the neurosurgical department opted against surgical intervention. The patient began antipsychotic therapy and was discharged having shown improvement (behavioural component), but without a complete remission of the psychotic symptoms. Conclusion It is difficult to be absolutely certain whether the lesion had influence on the patient's psychiatric symptoms or not. However, given the anatomical and neuropsychological changes, one cannot exclude the possibility that the lesion played a significant role in this psychiatric presentation. This raises substantial problems when it comes to choosing a
Chronic subdural hematoma associated with arachnoid cyst. Two case histories with pathological observations.
Takayasu, Takeshi; Harada, Kunyu; Nishimura, Shigeru; Onda, Jun; Nishi, Tohru; Takagaki, Hisashi
Arachnoid cysts are well known to induce chronic subdural hematoma (CSDH) after head injury. However, histological observations of the arachnoid cyst and hematoma membrane have only been rarely described. An 8-year-old boy and a 3-year-old boy presented with CSDH associated with arachnoid cyst. Surgical removal of the hematoma and biopsy of the hematoma membrane and cyst wall were performed. Clinical courses were good and without recurrence more than 1.5 years after surgery. Histological examination suggested that the cysts did not contribute to hematoma development. Pediatric hematoma membranes, similar to adult hematoma membranes, are key in the growth of CSDH. Therefore, simple hematoma evacuation is adequate as a first operation for CSDH associated with arachnoid cyst.
Dual lumbar bronchogenic and arachnoid cyst presenting with sciatica and left foot drop.
Candy, Nicholas; Young, Adam; Devadass, Abel; Dean, Andrew; McMillen, Jason; Trivedi, Rikin
Spinal bronchogenic cysts are rare findings, with only four cases of lumbar bronchogenic cysts reported in the literature. All of these bronchogenic cysts involved the conus medullaris. We present the first case of a lumbar bronchogenic cyst and arachnoid cyst arising from the cauda equina in a 68-year-old male. Uniquely, this bronchogenic cyst also contained components of an arachnoid cyst. Magnetic resonance imaging (MRI) demonstrated a compressive cystic lesion at the level of the L3 vertebra splaying the cauda equina. An L3/L4 laminectomy was performed with marsupialisation of the cyst. Histological examination revealed pseudostratified ciliated columnar epithelium confirming the diagnosis of a bronchogenic cyst, as well as a pleated fibrovascular tissue lined by sparsely spaced small monomorphic arachnoidal cells, indicating an arachnoid cyst. We demonstrate that bronchogenic cysts can be successfully treated with marsupialisation.
Location, sidedness, and sex distribution of intracranial arachnoid cysts in a population-based sample.
Helland, Christian A; Lund-Johansen, Morten; Wester, Knut
The aim of this study was to examine the distribution of intracranial arachnoid cysts in a large and unselected patient population with special emphasis on sidedness and sex distribution. In total, 299 patients with 305 arachnoid cysts were studied. These patients were consecutively referred to our department during a 20-year period from a well-defined geographical area with a stable population. There was a strong predilection (198 patients [66.2%]) for intracranial arachnoid cysts in the temporal fossa. Forty-two patients had cysts overlying the frontal convexity, 36 had cysts in the posterior fossa, and 23 patients had cysts in other, different locations. Of 269 cysts with clearly unilateral distribution, 163 were located on the left side and 106 on the right side. This difference resulted from the marked preponderance of temporal fossa cysts on the left side (left-to-right ratio 2.5:1; p < 0.0001 [adjusted < 0.0005]). For cysts in the cerebellopontine angle (CPA), there was preponderance on the right side (p = 0.001 [adjusted = 0.005]). Significantly more males than females had cysts in the temporal fossa (p = 0.002 [adjusted = 0.004]), whereas in the CPA a significant female preponderance was found (p = 0.016 [adjusted = 0.032]). For all other cyst locations, there was no difference between the 2 sexes. Arachnoid cysts have a strong predilection for the temporal fossa. There is a sex dependency for some intracranial locations of arachnoid cysts, with temporal cysts occurring more frequently in men, and CPA cysts found more frequently in women. Furthermore, there is a strong location-related sidedness for arachnoid cysts, independent of patient sex. These findings and reports from the literature suggest a possible genetic component in the development of some arachnoid cysts.
Ultrastructural characteristics of the cranial dura mater-arachnoid interface layer.
Angelov, D N
The ultrastructural features of the encephalic dura mater-arachnoid borderline (interface) layer (zone) of rats, rabbits, cats and humans were studied. The rat's interface zone included the electron-lucent epithelium-like arranged fibroblasts of the inner dural layer, the rich in filaments cells of the dural neurothelium, a 20 nm wide intercellular cleft filled with electron-dense material and the dark mitochondria-rich cells of the outer arachnoidal layer; in rabbits and cats, this laminar distinction was less prominent, while in man, it was almost absent.
Growth of arachnoid cysts in patients with autosomal dominant polycystic kidney disease: serial imaging and clinical relevance
Krauer, Fabienne; Ahmadli, Uzeyir; Kollias, Spyros; Bleisch, Jörg; Wüthrich, Rudolf P.; Serra, Andreas L.; Poster, Diane
Background Autosomal dominant polycystic kidney disease (ADPKD) is an inherited disorder that results in the growth of cysts in the kidneys and other organs. Multisystemic involvement is common including affection of the central nervous system with cerebral aneurysms and arachnoid cysts. Methods This is a prospective cohort study to investigate the prevalence and growth rate of arachnoid cysts in ADPKD patients. Participants enrolled in the SUISSE ADPKD cohort were offered cranial imaging for the detection of intracranial alterations. In the case of identified arachnoid cysts, patients were suggested to undergo follow-up imaging to assess the growth rate of the cysts. Volume of arachnoid cysts at the baseline and at follow-up visits was assessed by manual segmentation on a dedicated workstation. Results A total of 109 ADPKD patients agreed to undergo cranial imaging. In 14 (12.8%) patients (9 males and 5 females), 18 singular arachnoid cysts were identified. The baseline volumes of individual cysts ranged from 1.8 to 337.6 cm3. During a mean follow-up period of 24 months, the volume changes of 12 individual arachnoid cysts of nine patients ranged from −3.1 to 3.7 cm3. Cystic lesions were mostly localized in the middle fossa. All affected patients were clinically asymptomatic. Conclusions We found a higher prevalence of arachnoid cysts in ADPKD patients with more advanced disease. There was a large variability in size and growth. These arachnoid cysts were clinically silent and their growth pattern was subtle and unpredictable, in contrast to the much more foreseeable growth of the renal cysts. PMID:26019816
Electron Microscopy of Dural and Arachnoid Disruptions After Subarachnoid Block.
Reina, Miguel Angel; Puigdellívol-Sánchez, Anna; Gatt, Stephen P; De Andrés, José; Prats-Galino, Alberto; van Zundert, André
It has been customary to attribute postdural puncture headache (PDPH) incidence and severity to size and nature of the dural hole produced during major neuraxial blockade or diagnostic dural puncture. Needle orientation in relation to the direction of dural fibers was thought to be of importance because of the propensity for horizontal bevel placement to cause cutting rather than splitting of the dural fibers. In vitro punctures of stringently quality-controlled human dural sac specimens were obtained with 27-gauge (27G) Whitacre needle (n = 33), with 29G Quincke used parallel to the spinal axis (n = 30), and with 29G Quincke in perpendicular approach (n = 40). The samples were studied with a scanning electron microscope, and the perimeter, appearance, and area (%) of the lesion were calculated. When using small 27G to 29G needles, neither needle tip characteristics nor needle orientation had a substantial bearing on the damage to dural fibers in the dural lesion. Of ultimate importance was the characteristic and size of the hole in the arachnoid. Arachnoid layer lesions produced by different types of spinal needles were not markedly different. Accepted theories of the etiology of PDPH need to be revised. This article marks the first time that arachnoid layer damage has been quantified. Dural fibers tend to have sufficient "memory" to close back the hole created by a spinal needle, whereas arachnoid has diminished capacity to do so. The pathogenesis of PDPH and its resolution algorithm are a far more complex process that involves many more "stages" of development than hitherto imagined.
Cranial nerve VI palsy after dural-arachnoid puncture.
Hofer, Jennifer E; Scavone, Barbara M
In this article, we provide a literature review of cranial nerve (CN) VI injury after dural-arachnoid puncture. CN VI injury is rare and ranges in severity from diplopia to complete lateral rectus palsy with deviated gaze. The proposed mechanism of injury is cerebrospinal fluid leakage causing intracranial hypotension and downward displacement of the brainstem. This results in traction on CN VI leading to stretch and neural demyelination. Symptoms may present 1 day to 3 weeks after dural-arachnoid puncture and typically are associated with a postdural puncture (spinal) headache. Resolution of symptoms may take weeks to months. Use of small-gauge, noncutting spinal needles may decrease the risk of intracranial hypotension and subsequent CN VI injury. When ocular symptoms are present, early administration of an epidural blood patch may decrease morbidity or prevent progression of ocular symptoms.
Temporo-sylvian arachnoidal cyst and an extreme pneumatization of the cranial sinuses: a case report.
Zara, Gabriella; Ponza, Isabella; Citton, Valentina; Manara, Renzo
We present a patient who showed MRI evidence of a giant temporo-sylvian arachnoidal cyst of the left hemisphere and an extreme pneumatization of the sphenoid and frontal sinuses. No sign of mass effect or cerebral atrophy was detected. This patient presented a deficit of memory and control functions, but quality of life was not affected. Surgery was not performed. Arachnoidal cyst and anatomic variants of the sinus region have not a common etiology. This is the first report that describes a giant temporo-sylvian arachnoidal cyst with anatomic variants of the paranasal sinuses. Copyright © 2010 Elsevier B.V. All rights reserved.
Peculiarities of intracranial arachnoid cysts: location, sidedness, and sex distribution in 126 consecutive patients.
To study the distribution of intracranial arachnoid cysts in a large and nonbiased patient population. One hundred twenty-six patients with 132 arachnoid cysts were studied. Patients were consecutively referred to our department during a 10-year period from a well-defined geographical area with a stable population. The cysts had a strong predilection for the middle cranial fossa; 86 patients (65.2%) had cysts in this location. Of 106 cysts with clearly unilateral distribution, 64 were located on the left side and 42 on the right side. This significant difference resulted solely from the marked preponderance of middle fossa cysts for the left (left-to-right ratio, 2.1:1). There were significantly more males than females (92 males/34 females). This difference was exclusively due to male preponderance of unilateral middle fossa cysts (66 males/14 females; ratio, 4.7:1). For all other cyst locations, there was no difference between the two sexes (26 males/20 females) or the two sides (10 left, 16 right). The marked left-sidedness for middle fossa cysts was found only in males. Females had an even distribution between the two sides. Arachnoid cysts have a strong predilection for the middle cranial fossa that may be explained by a meningeal maldevelopment theory: the arachnoid coverings of the temporal and frontal lobes fail to merge when the sylvian fissure is formed in early fetal life, thereby creating a noncommunicating fluid compartment entirely surrounded by arachnoid membranes. Why males develop more middle fossa cysts on the left side remains a mystery.
A New Classification for Pathologies of Spinal Meninges-Part 2: Primary and Secondary Intradural Arachnoid Cysts.
Spinal intradural arachnoid cysts are rare causes of radiculopathy or myelopathy. Treatment options include resection, fenestration, or cyst drainage. To classify intradural spinal arachnoid cysts and present results of their treatment. Among 1519 patients with spinal space occupying lesions, 130 patients demonstrated intradural arachnoid cysts. Neuroradiological and surgical features were reviewed and clinical data analyzed. Twenty-one patients presented arachnoid cysts as a result of an inflammatory leptomeningeal reaction related to meningitis, subarachnoid hemorrhage, intrathecal injections, intradural surgery, or trauma, ie, secondary cysts. For the remaining 109 patients, no such history could be elucidated, ie, primary cysts. Forty-six percent of primary and 86% of secondary cysts were associated with syringomyelia. Patients presented after an average history of 53 ± 88 months. There were 122 thoracic and 7 lumbar cysts plus 1 cervical cyst. Fifty-nine patients with primary and 15 patients with secondary cysts underwent laminotomies with complete or partial cyst resection and duraplasty. Mean follow-up was 57 ± 52 months. In the first postoperative year, profound improvements for primary cysts were noted, in contrast to marginal changes for secondary cysts. Progression-free survival for 10 years following surgery was determined as 83% for primary compared to 15% for secondary cysts. Despite differences in clinical presentation, progression-free survival was almost identical for patients with or without syringomyelia. Complete or partial resection leads to favorable short- and long-term results for primary arachnoid cysts. For secondary cysts, surgery can only provide clinical stabilization for a limited time due to the often extensive arachnoiditis. Copyright © 2017 by the Congress of Neurological Surgeons
A patient with myasthenia gravis and a large arachnoid cyst - report of a case.
Bucuk, Mira; Gasparovic, Iva; Sonnenschein, Ivan; Perkovic, Olivio
Myasthenia gravis is a chronic autoimmune disease characterized by weakening of voluntary muscles during the day and a marked restitution of function during the night and after rest. The symptoms may worsen over days or weeks, sometimes even in a few hours, and are usually well controlled by appropriate therapy. Arachnoid cysts are congenital or acquired deformities of the arachnoid membrane and are usually too small to cause distinct clinical symptomatology. We describe a case of a 76-year-old myasthenia gravis patient with an arachnoid cyst. To the best of our knowledge this is the first reported case of these two comorbidities together.
Syringomyelia caused by an arachnoid web in a patient with shunted Dandy-Walker malformation.
Lee, Hee Chang; Choi, Jung Won; Lee, Ji Yeoun; Phi, Ji Hoon; Kim, Seung-Ki; Cho, Byung-Kyu; Wang, Kyu-Chang
Dandy-Walker malformation (DWM) is a congenital brain anomaly characterized by dysgenesis of the cerebellar vermis and the presence of a posterior fossa cyst. The association of syringomyelia with DWM is extremely rare. A 10-year-old patient who was diagnosed with DWM in infancy presented with progressive scoliosis and fecal incontinence. He had been treated with cystoventriculoperitoneal shunting with a Y-connection during infancy, which was followed by a revision 6 years later. During the revision surgery, intraventricular bleeding occurred and was managed conservatively. Imaging studies for the current visit revealed syringomyelia along the cervicothoracic spinal cord and a membranous structure around the cervicomedullary junction. Phase-contrast cine magnetic resonance imaging (MRI) revealed disturbed cerebrospinal fluid (CSF) flow across the membrane. We excised the arachnoid web that was tethering the brainstem and blocking CSF flow. Postoperatively, the patient experienced symptom relief, and the follow-up imaging study demonstrated a dramatic decrease in the size of the syringomyelia. We suggest that syrinx formation in this patient was possibly caused by disturbed CSF flow and tethering of the brainstem. We experienced an unusual case of DWM with syringomyelia which was caused by an arachnoid web blocking CSF flow and tethering the brainstem. The arachnoid web seems to be formed by previous bleeding which occurred at the time of shunt revision. After excision of the arachnoid web, the patient showed good outcome.
Microsurgery Simulator of Cerebral Aneurysm Clipping with Interactive Cerebral Deformation Featuring a Virtual Arachnoid.
Shono, Naoyuki; Kin, Taichi; Nomura, Seiji; Miyawaki, Satoru; Saito, Toki; Imai, Hideaki; Nakatomi, Hirofumi; Oyama, Hiroshi; Saito, Nobuhito
A virtual reality simulator for aneurysmal clipping surgery is an attractive research target for neurosurgeons. Brain deformation is one of the most important functionalities necessary for an accurate clipping simulator and is vastly affected by the status of the supporting tissue, such as the arachnoid membrane. However, no virtual reality simulator implementing the supporting tissue of the brain has yet been developed. To develop a virtual reality clipping simulator possessing interactive brain deforming capability closely dependent on arachnoid dissection and apply it to clinical cases. Three-dimensional computer graphics models of cerebral tissue and surrounding structures were extracted from medical images. We developed a new method for modifiable cerebral tissue complex deformation by incorporating a nonmedical image-derived virtual arachnoid/trabecula in a process called multitissue integrated interactive deformation (MTIID). MTIID made it possible for cerebral tissue complexes to selectively deform at the site of dissection. Simulations for 8 cases of actual clipping surgery were performed before surgery and evaluated for their usefulness in surgical approach planning. Preoperatively, each operative field was precisely reproduced and visualized with the virtual brain retraction defined by users. The clear visualization of the optimal approach to treating the aneurysm via an appropriate arachnoid incision was possible with MTIID. A virtual clipping simulator mainly focusing on supporting tissues and less on physical properties seemed to be useful in the surgical simulation of cerebral aneurysm clipping. To our knowledge, this article is the first to report brain deformation based on supporting tissues.
Intramedullary cyst formation after removal of multiple intradural spinal arachnoid cysts: A case report
Zekaj, Edvin; Saleh, Christian; Servello, Domenico
Background: A rare cause of spinal cord compression is spinal arachnoid cysts. Symptoms are caused by spinal cord compression, however, asymptomatic patients have been also reported. Treatment options depend upon symptom severity and clinical course. Case Description: We report the case of a 47-year-old patient who developed an intramedullary arachnoid cyst after removal of an intradural extramedullary cyst. Conclusion: Surgery should be considered early in a symptomatic disease course. Longstanding medullary compression may reduce the possibility of neurological recovery as well as secondary complications such as intramedullary cyst formation. PMID:27512608
[Suprasellar arachnoid cyst--report of a case (author's transl)].
Takahashi, T; Kawai, S; Kaminoh, T; Hiramatsu, K; Maekawa, M; Yuasa, T; Miyamoto, N; Hattori, Y
A 4-year-old boy with suprasellar arachnoid cyst was reported. At the age of 30-month-old his aunt was aware of his squint. During the observation by ophthalmologists from the age of 1y. to 3y., enlargement of the head and impairment of the visual acuity were manifested. Cranial CT scan revealed the enlargement of the ventricular system and a round low density area located superior to the sella. Absorption coefficient of the lesion was similar to that of the cerebrospinal fluid. No abnormal contrast enhancement was seen. Examination revealed the head circumference of 53.3 cm larger than doubled standard deviation, the right external strabismus, impaired vision (R:0.03, L:0.3) and optic atrophy but no other neurological signs. Cerebral angiography showed suprasellar mass lesion. After the ventriculography with water-soluble contrast medium, V-P shunt operation was performed and then the patient was transferred to the CT room. CSF enhanced CT scan showed no communication between the ventricles and the cyst. By frontotemporal approach, microsurgical removal of the cystwall was performed and the histological diagnosis was arachnoid membrane. Several days after the operation, bilateral subdural effusion was seen on CT scan and was treated with bilateral S-P shunt and the removal of V-P shunt. Follow up CT scan disclosed the disappearance of the subdural effusion and the suprasellar cyst. The visual acuity was improved well and the endocrinological study was normal. Analysis of the 45 reported cases of suprasellar arachnoid cyst suggested that direct removal of the cyst wall is better than the V-P shunt operation and the cyst shunting is advisable for repeat recurrence of the cyst. Removal of the ventricular shunting system may be effective for the prevention of the subdural effusion as a complication after direct operation.
Intradural Extramedullary Capillary Hemangioma In the Upper Thoracic Spine with Simultaneous Extensive Arachnoiditis
Lee, Jae Ho; Jeon, Ikchan; Kim, Sang Woo
Capillary hemangiomas are common benign vascular tumors on skin and soft tissues, but developing as an intradural and extramedullary (IDEM) tumor in spine is extremely rare. In this report, we present IDEM tumor compressing thoracic cord in T2–3 level with extensive arachnoiditis below the tumor level in a 60-year-old man. The lesion was removed and histological diagnosis was capillary hemangioma. Prompt diagnosis and resection are important to avoid neurological deterioration from acute hemorrhagic condition. Simultaneous arachnoiditis may be originated from old subarachnoid hemorrhage associated tumor before diagnosis, and we suggest it as a helpful diagnostic feature to suspect vascular tumors such as capillary hemangioma. PMID:28704911
Intradural Extramedullary Capillary Hemangioma In the Upper Thoracic Spine with Simultaneous Extensive Arachnoiditis.
Lee, Jae Ho; Jeon, Ikchan; Kim, Sang Woo
Capillary hemangiomas are common benign vascular tumors on skin and soft tissues, but developing as an intradural and extramedullary (IDEM) tumor in spine is extremely rare. In this report, we present IDEM tumor compressing thoracic cord in T2-3 level with extensive arachnoiditis below the tumor level in a 60-year-old man. The lesion was removed and histological diagnosis was capillary hemangioma. Prompt diagnosis and resection are important to avoid neurological deterioration from acute hemorrhagic condition. Simultaneous arachnoiditis may be originated from old subarachnoid hemorrhage associated tumor before diagnosis, and we suggest it as a helpful diagnostic feature to suspect vascular tumors such as capillary hemangioma.
Acute hydrocephalus in a child with a third ventricle arachnoid cyst and coincidental enteroviral meningitis.
Jeltema, Hanne-Rinck; Kuijlen, Jos M A; Hoving, Eelco W
We present a 2.5-year-old child suffering from acute hydrocephalus. First, the child was diagnosed with aseptic viral meningitis. The PCR of the cerebrospinal fluid (CSF) was positive for enterovirus. Subsequently, MRI revealed that the hydrocephalus was caused by a cyst in the third ventricle. During ventriculoscopy, the cyst had all aspects of an arachnoid cyst. An endoscopic fenestration and partial removal of the cyst was performed, combined with a ventriculocisternostomy. The coincidental finding of viral meningitis and a third ventricle arachnoid cyst in a patient with acute hydrocephalus has, to our knowledge, not been described in literature before. If there is a relation between the enteroviral meningitis, the arachnoid cyst (possibly causing a pre-existing subclinical hydrocephalus) and the rapidly evolving neurological deterioration, remains speculative. Proposed mechanisms, by which the viral meningitis could accelerate the disease process, are slight brain swelling or increased CSF production. This rare combination of diagnoses could also be coincidental.
Dura-arachnoid lesions produced by 22 gauge Quincke spinal needles during a lumbar puncture.
Reina, M A; López, A; Badorrey, V; De Andrés, J A; Martín, S
The dural and arachnoid hole caused by lumbar puncture needles is a determining factor in triggering headaches. The aim of this study is to assess the dimensions and morphological features of the dura mater and arachnoids when they are punctured by a 22 gauge Quincke needle having its bevel either in the parallel or in the transverse position. Fifty punctures were made with 22 gauge Quincke needles in the dural sac of four fresh cadavers using an "in vitro" model especially designed for this purpose. The punctures were performed by needles with bevels parallel or perpendicular to the spinal axis and studied under scanning electron microscopy. Thirty five of the 50 punctures done by Quincke needles (19 in the external surface and 16 in the internal) were used for evaluation. When the needle was inserted with its bevel parallel to the axis of the dural sac (17 of 35), the size of the dura-arachnoid lesion was 0.032 mm(2) in the epidural surface and 0.037 mm(2) in the subarachnoid surface of the dural sac. When the needle's bevel was perpendicular to the axis (18 of 35) the measurement of the lesion size was 0.042 mm(2) for the external surface and 0.033 mm(2) for the internal. There were no statistical significant differences between these results. It is believed that the reported lower frequency of postdural puncture headache when the needle is inserted parallel to the cord axis should be explained by some other factors besides the size of the dura-arachnoid injury.
Minimizing Retraction by Pia-Arachnoidal 10-0 Sutures in Intrasulcal Dissection.
Uluc, Kutluay; Cikla, Ulas; Morkan, Deniz B; Sirin, Alperen; Ahmed, Azam S; Swanson, Kyle; Baskaya, Mustafa K
In contemporary microneurosurgery reducing retraction-induced injury to the brain is essential. Self-retaining retractor systems are commonly used to improve visualization and decrease the repetitive microtrauma, but sometimes self-retaining retractor systems can be cumbersome and the force applied can cause focal ischemia or contusions. This may increase the morbidity and mortality. Here, we describe a technique of retraction using 10-0 sutures in the arachnoid. To evaluate the imaging and clinical results in patients where 10-0 suture retraction was used to aid the surgical procedure. Adjacent cortex was retracted by placing 10-0 nylon suture in the arachnoid of the bank or banks of the sulcus. The suture was secured to the adjacent dural edge by using aneurysm clips, allowing for easy adjustability of the amount of retraction. We retrospectively analyzed the neurological outcome, signal changes in postoperative imaging, and ease of performing surgery in 31 patients with various intracranial lesions including intracranial aneurysms, intra- and extra-axial tumors, and cerebral ischemia requiring arterial bypass. Clinically, there were no injuries, vascular events, or neurological deficits referable to the relevant cortex. Postoperative imaging did not show changes consistent with ischemia or contusion due to the retraction. This technique improved the visualization and illumination of the surgical field in all cases. Retraction of the arachnoid can be used safely in cases where trans-sulcal dissection is required. This technique may improve initial visualization and decrease the need for dynamic or static retraction.
Dura-arachnoid lesions produced by 22 gauge Quincke spinal needles during a lumbar puncture
Reina, M; Lopez, A; Badorrey, V; De Andres, J A; Martin, S
Aims: The dural and arachnoid hole caused by lumbar puncture needles is a determining factor in triggering headaches. The aim of this study is to assess the dimensions and morphological features of the dura mater and arachnoids when they are punctured by a 22 gauge Quincke needle having its bevel either in the parallel or in the transverse position. Methods: Fifty punctures were made with 22 gauge Quincke needles in the dural sac of four fresh cadavers using an "in vitro" model especially designed for this purpose. The punctures were performed by needles with bevels parallel or perpendicular to the spinal axis and studied under scanning electron microscopy. Results: Thirty five of the 50 punctures done by Quincke needles (19 in the external surface and 16 in the internal) were used for evaluation. When the needle was inserted with its bevel parallel to the axis of the dural sac (17 of 35), the size of the dura-arachnoid lesion was 0.032 mm2 in the epidural surface and 0.037 mm2 in the subarachnoid surface of the dural sac. When the needle's bevel was perpendicular to the axis (18 of 35) the measurement of the lesion size was 0.042 mm2 for the external surface and 0.033 mm2 for the internal. There were no statistical significant differences between these results. Conclusions: It is believed that the reported lower frequency of postdural puncture headache when the needle is inserted parallel to the cord axis should be explained by some other factors besides the size of the dura-arachnoid injury. PMID:15146008
Immunohistochemical localization of cell adhesion molecule epithelial cadherin in human arachnoid villi and meningiomas.
Tohma, Y; Yamashima, T; Yamashita, J
Cadherins are a family of intercellular glycoproteins responsible for calcium-dependent cell adhesion and are currently divided into four types: epithelial (E), neuronal (N), placental (P), and vascular (V). Since cadherins are known to be indispensable for not only morphogenesis in the embryo but also maintenance of tumor cell nest, we examined the expression of E-cadherin in 31 meningiomas (11 syncytial, 12 transitional, 8 fibroblastic) and 3 arachnoid villi by immunoblot and immunohistochemical analyses. In the immunoblot analysis, E-cadherin was detected at the main band of Mr 124,000 in all of the arachnoid villi, as well as syncytial and transitional types of meningiomas, but not in the fibroblastic type. The immunohistochemical examination showed that E-cadherin was expressed at the cell borders of syncytial and transitional types, but the expression was absent in the fibroblastic type. Immunoelectron microscopy showed that E-cadherin was localized at the intermediate junctions in arachnoid villi, while it was detected diffusely at the cell surface in meningiomas. It is suggested from these data that the expression of E-cadherin might be closely related to the differentiation and organogenesis of meningioma cells.
Benign occipital unicameral bone cyst causing lower cranial nerve palsies complicated by iophendylate arachnoiditis
Bradley, W. G.; Kalbag, R. M.; Ramani, P. S.; Tomlinson, B. E.
A 20 year old girl presented with a history of neck and occipital pain for six weeks, which was found to be due to a unicameral bone cyst of the left occipital condylar region. The differential diagnosis of bone cysts in the skull is discussed. Six months after the operation, the patient again presented with backache due to adhesive arachnoiditis. The latter was believed to have arisen as a result of a combination of spinal infective meningitis and intrathecal ethyl iodophenyl undecylate (iophendylate, Myodil, Pantopaque). The nature of meningeal reactions to iophendylate and the part played by intrathecal corticosteroids in relieving the arachnoiditis in the present case are discussed. Images
Cauda equina syndrome associated with multiple lumbar arachnoid cysts in ankylosing spondylitis: improvement following surgical therapy.
Shaw, P J; Allcutt, D A; Bates, D; Crawford, P J
A case of cauda equina syndrome with multiple lumbar arachnoid cysts complicating ankylosing spondylitis (AS) is described. The value of computerised tomography (CT) and magnetic resonance imaging (MRI) as a non-invasive means of establishing the diagnosis is emphasised. In contrast to previously reported cases the patient showed neurological improvement following surgical therapy. Surgery may be indicated in some patients, particularly when there is nerve root compression by the arachnoid cysts and when the patient is seen early before irreversible damage to the cauda equina has occurred. Images PMID:2292702
Supraorbital Keyhole Microsurgical Fenestration of Symptomatic Temporal Arachnoid Cysts in Children: Advantages and Limitations.
Elkheshin, Sherif; Soliman, Ahmed
To investigate the impact of endoscope-assisted microsurgical fenestration on temporal arachnoid cysts, and to determine the advantages and limitations of the technique. Twenty-five children with symptomatic temporal arachnoid cysts were operated via eyebrow supraorbital keyhole microsurgical fenestration targeting the medial cyst wall. Preoperative magnetic resonance imaging (MRI) of the brain was done for all patients. Preoperative clinical presentation of the patients included headache (80%), nausea & vomiting (64%), drug resistant epilepsy (52%), macrocephaly (12%) papilledema (28%), motor weakness in the form of right-sided hemiparesis (12%) and cranial nerve palsy. Postoperative complete subsidence of headache was noted in 50%, while 20% remained unchanged. Drug resistant epilepsy improved in 69% of the patients. Postoperative MRI showed initial decrease in cyst volume as early as 3 months, only in a range of 5-12% volume reduction, and the late follow-up done at 6 and 18 months continued to show further reduction reported to be significant (p < 0.001). Transient subgaleal cerebrospinal fluid (CSF) collection was the most common complication (20%). Only 1 patient experienced CSF leak mandating cysto-peritoneal shunting. Conclusıon: Eyebrow supraorbital keyhole microsurgical fenestration for temporal arachnoid cysts can be performed with a fairly low risk of complications and yields a favorable improvement in clinical and neuroimaging outcomes.
Suprasellar arachnoid cyst after subdural haemorrhage in an infant. A case based update.
Sonnet, M-H; Joud, A; Marchal, J-C; Klein, O
Brain arachnoid cysts (AC) are congenital or acquired malformations. Their prevalence in children ranges between 0.2 and 2.3% of the studied populations. Few reported studies exist where AC appears after a subdural haemorrhage. We present one case of a symptomatic suprasellar AC after post-traumatic subdural haemorrhage in an infant. After endoscopic ventriculocystostomy, the child quickly improved and the cyst reduced in size. The child was monitored for 22 months and his neurocognitive development remained normal. Our case led us to the hypothesis that the inflammatory process due to subdural haemorrhage may locally result in arachnoiditis, and thus to the creation of a neomembrane, and eventually to cyst formation. This is also the case with the development of post-traumatic spinal AC. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
De Novo Intraneural Arachnoid Cyst Presenting with Complete Third Nerve Palsy: Case Report and Literature Review.
Brewington, Danielle; Petrov, Dmitriy; Whitmore, Robert; Liu, Grant; Wolf, Ronald; Zager, Eric L
Intraneural arachnoid cyst is an extremely rare etiology of isolated cranial nerve palsy. Although seldom encountered in clinical practice, this pathology is amenable to surgical intervention. Correct identification and treatment of the cyst are required to prevent permanent nerve damage and potentially reverse the deficits. We describe a rare case of isolated third nerve palsy caused by an intraneural arachnoid cyst. A 49-year-old woman with a recent history of headaches experienced acute onset of painless left-sided third nerve palsy. According to hospital records ptosis, mydriasis, absence of adduction, elevation, and intorsion were noted in the left eye. Computed tomography and magnetic resonance imaging studies showed an extra-axial, 1-cm lesion along the left paraclinoid region, causing mild indentation on the uncus. There was dense fluid layering dependently concerning for hemorrhage, but no evidence of aneurysms. A pterional craniotomy was performed, revealing a completely intraneural arachnoid cyst in the third nerve. The cyst was successfully fenestrated. At 7-month follow-up, the left eye had recovered intact intorsion and some adduction, but the left pupil remained dilated and nonreactive. There was still no elevation and no afferent pupillary defect. Double vision persisted with partial improvement in the ptosis, opening up to more than 75% early in the day. To our knowledge, this is the first report of an intraneural arachnoid cyst causing isolated third nerve palsy. This rare pathology proves to be both a diagnostic and therapeutic challenge. Copyright © 2016 Elsevier Inc. All rights reserved.
Rare case of diffuse spinal arachnoiditis following a complicated vertebral artery dissection.
Atallah, Elias; Dang, Sophia; Rahm, Sage; Feghali, James; Nohra, Chalouhi; Tjoumakaris, Stavropoula; Rosenwasser, Robert H; Zarzour, Hekmat; Herial, Nabeel; Gooch, Michael Reid; Jabbour, Pascal
Spinal arachnoiditis (SA) is an extremely rare and delayed complication of subarachnoid hemorrhage (SAH). Little is known about its underlying pathogenesis and subsequent clinical course. A middle-aged patient presented with the worst headache of her life and a grade 3 SAH of the basal-cisterns and posterior fossa was identified on Computed Tomography scans (CT). Angiography revealed a ruptured dissecting aneurysm of the left vertebral artery (VA-V4), as well as an unruptured left Anterior Cerebral Artery (ACA-A1) aneurysm. The VA aneurysm was treated with flow diversion. The patient re-ruptured the stented aneurysm, another telescoping pipeline was placed. The patient developed polymicrobial ventriculitis, and returned several months later complaining of paraparesis and left sided weakness. Magnetic Resonance Imaging (MRI) revealed diffuse thecal dural thickening from the cervicomedullary junction to the sacrum. Loculations, diffuse edema and cord compression were noticed along the inferior surface of the cerebellum, and the cervico-thoracic spine with a T4-T6 syrinx. The patient underwent a posterior (T4-T8) spinal fusion and (T5-T7) decompression with arachnoid-cyst fenestration and placement of a subarachnoid-pleural shunt. On latest follow-up, the patient is weaning off the thoraco-lumbosacral orthosis and ambulating with a cane. SA is often a complicated two-staged disease in which a "free interval phase" separates the initial inflammatory reaction (IIR) from the late adhesive phase. Posterior fossa bleeding, warranting prolonged surveillance, additional bleeding and ventriculitis might augment the risk and the severity of arachnoiditis. Copyright © 2018 Elsevier Ltd. All rights reserved.
Arachnoid Cyst in the Middle Cranial Fossa Presenting with Pulsatile Exophthalmos: Case Report and Literature Review
SAITO, Atsushi; KON, Hiroyuki; HARYU, Shinya; MINO, Masaki; SASAKI, Tatsuya; NISHIJIMA, Michiharu
A 20-year-old woman suffered gradual progression of right pulsatile exophthalmos and slight headache. Computed tomography (CT) demonstrated outward and downward displacement of the right globe and an arachnoid cyst in the right middle cranial fossa associated with thinned and anterior protrusion of a bony orbit. Microscopic cystocisternotomy was performed and the cerebrospinal fluid (CSF) inside of the cyst communicated into the carotid cistern and cistern in the posterior cranial fossa. Pulsatile exophthalmos improved immediately after surgery. Arachnoid cyst in the middle cranial fossa presenting with exophthalmos is rare. Microscopic cystocisternotomy might successfully improve CSF flow and relieve exophthalmos. PMID:24305013
Anatomic Dissection of Arachnoid Membranes Encircling the Pituitary Stalk on Fresh, Non-Formalin-Fixed Specimens: Anatomoradiologic Correlations and Clinical Applications in Craniopharyngioma Surgery.
Ciappetta, Pasqualino; Pescatori, Lorenzo
The anatomy of the arachnoid membranes and cisternal spaces around the pituitary stalk has not been yet exhaustively described and understood. In this study, we performed a detailed anatomic study on fresh, non-formalin-fixed cadavers of the arachnoid membranes encircling the pituitary stalk and correlate our anatomic findings with magnetic resonance imaging (MRI). Ten fresh, non-formalin-fixed, non-silicon-injected adult cadaveric heads were analyzed in this study. The membrane and cisterns that were studied for our study were as follows: 1) the diaphragma sellae and its dural components; 2) the basal arachnoid membrane; 3) the Liliequist membrane with its diencephalic and mesencephalic portion; 4) the medial carotid membrane; 5) the chiasmatic cistern; and 6) the pituitary stalk. MRI examinations of the sellar region were performed in 15 healthy volunteers (9 men, mean age 40 years; and 6 women mean age, 37 years) to visualize the arachnoid membrane encircling the pituitary stalk. MRI examinations were performed with a 3-T unit. A 3-dimensional constructive interference in steady state pulse magnetic resonance sequence was used. All the membranes examined were visualized clearly in all the dissections performed. Their 3-dimensional organization around the pituitary stalk was clarified and confirmed by MRI. Our study gives a detailed description of the pituitary stalk arachnoid sheets on fresh, non-formalin-fixed cadavers. This technique allowed us to clearly identify a funnel-shaped arachnoid collar encircling the pituitary stalk and delimiting a distinct cisternal space belonging to the stalk itself. Copyright © 2017 Elsevier Inc. All rights reserved.
Clinical and radiological outcomes of surgical treatment for symptomatic arachnoid cysts in adults.
Wang, Yongqian; Wang, Fei; Yu, Mingkun; Wang, Weiping
We retrospectively analyzed 63 patients (31 males and 32 females) with arachnoid cysts managed over a 15 year period at our institution. Surgical indications and modalities for the treatment of intracranial arachnoid cysts are controversial, although endoscopic fenestration is often recommended as a standard procedure. In our cohort, clinical postoperative results and radiological assessments based on the presenting symptoms, cyst location, cyst volume and surgical modalities were recorded. The most common symptoms included headaches (66.7%), dizziness (46%) and seizures (36.5%). Cyst wall excision with microsurgical craniotomy was carried out in 28 patients (44.4%), cyst fenestration in 16 (25.4%), cystoperitoneal or ventriculoperitoneal shunting in 15 (23.8%) and endoscopic fenestration in four patients (6.3%). A satisfactory clinical outcome was achieved in 51 patients (80.9%) and cyst reduction was achieved in 49 (77.8%), at the last follow-up. Clinical improvement correlated significantly with volume reduction in patients with suprasellar and infratentorial cysts (r=0.495; p=0.022) while a similar result was not found after surgery in patients with frontal and temporal cysts. Surgical complications were not correlated with surgical modalities, occurring in only seven patients (11.1%). The various surgical modalities did not influence outcomes. Patients with nonspecific symptoms such as headache may obtain favourable outcomes from surgical treatment with no severe complications, although, intracranial hypertension and neurological deficits are more definite surgical indications for arachnoid cysts. Copyright © 2015 Elsevier Ltd. All rights reserved.
Imaging characteristics of cervical spine extra-arachnoid fluid collections managed conservatively.
Lawrence, David A; Trotta, Brian; Shen, Francis H; Druzgal, Jason T; Fox, Michael G
Determine the MRI characteristics of large post-traumatic cervical spine extra-arachnoid collections managed conservatively in clinically stable patients and whether evidence of clinical or imaging deterioration materialized. Following IRB approval, we conducted a retrospective search for all patients (>16 years old) over a 17-months period who had an extra-arachnoid fluid collection reported on a post-traumatic cervical spine MRI. Patients were excluded if they had surgery for an unstable fracture (n = 21), emergent decompression (n = 1) or lacked a follow-up MRI within 15 days (n = 1). Two MSK radiologists recorded the size, morphology and MRI signal characteristics of the collections. Eight patients (5 male, 3 female) met the inclusion criteria (mean age 40 years; range 19-78 years). Seven of the eight patients had fluid collections that demonstrated thin, tapered margins, extended >7 vertebral bodies and involved >180 degrees of the spinal canal. The signal characteristics of these collections varied: hyper-T1/iso-T2 (n = 1), iso-T1/T2 (n = 3), hyper-T1/hypo-T2 (n = 3) and mixed-T1/T2 (n = 1). Six of seven collections were ventral. Follow-up MRI demonstrated resolution/significant decrease in size (n = 4 between 1 and 12 days) or no change/slight decrease in size (n = 3; between 2 and 11 days). None of the seven fluid collections enlarged, no patient had abnormal cord signal, and no patient's neurologic symptoms worsened. One of eight patients had a dorsal "mass-like" collection that was slightly smaller 9 days later. In stable patients with large, tapered post-traumatic cervical spine extra-arachnoid collections managed non-surgically, none developed (1) clinical worsening, (2) abnormal cord signal or (3) collection enlargement, regardless of the collection's signal characteristics.
Congenital supratentorial meningeal arteriovenous malformation with hemangioma and massive arachnoid cell hyperplasia.
Nabeel, Alnaghmoosh; Lach, Boleslaw; Al-Shail, Essam; Patay, Zoltan
We describe the clinical, radiological and pathological findings of concurrent, congenital leptomeningeal arteriovenous malformation with hemangioma diagnosed in a newborn by prenatal and immediately postnatal magnetic resonance imaging. Vascular abnormalities were accompanied by massive arachnoidal cell hyperplasia reminiscent of meningioma. To the best of our knowledge, this is the first case of such a lesion reported in the literature.
[Management of arachnoid cysts of the middle cranial fossa accompanied by subdural effusions].
Abderrahmen, K; Saadaoui, K; Bouhoula, A; Boubaker, A; Jemel, H
Subdural effusions are uncommon but known complications of arachnoid cysts of the middle cranial fossa. They mainly occur after minor head traumas in young patients. Here, we report eight cases of arachnoid cyst of the middle cranial fossa associated with subdural hematoma in five cases and hygroma in three cases. Major symptoms are signs of raised intracranial pressure. CT scan and MRI showed the cyst and the subdural effusion. An excellent therapeutic result was achieved with evacuation of the subdural fluid via burr holes in the five cases of subdural hematoma while in the two cases of hygroma a subduro-peritoneal shunt was necessary. In the last case, a temporal craniotomy was performed with evacuation of the hygroma and fenestration of the cyst. We suggest treating only the complicating event in the case of a subdural hematoma via burr holes evacuation. Whereas, in the case of hygroma we think that craniotomy with fenestration of the cyst or the use of a subdural shunt are more often needed. Copyright © 2012 Elsevier Masson SAS. All rights reserved.
Spinal intradural hydatid cyst causing arachnoiditis: A rare etiology of cauda equina syndrome
Singh, Suyash; Sardhara, Jayesh; Singh, Amit Kumar; Srivastava, Arun Kumar; Bhaisora, Kamlesh Singh; Das, Kuntal Kanti; Mehrotra, Anant; Sahu, Rabi N; Jaiswal, Awadhesh Kumar; Behari, Sanjay
This study aims to focus on a rare presentation of spinal hydatid cyst as cauda equine syndrome and misdiagnosed as intradural extramedullary (IDEM) benign lesion on magnetic resonance imaging. In this article, we report a case of spinal hydatid cyst masquerading as IDEM tumor, and intraoperatively, we accidently find clumped granuloma with severe arachnoiditis and hydatid cyst in lumber region, which was present as bilateral S1 radiculopathy with cauda equina syndrome. An 11-year-old boy who presented with symptoms and signs of cauda equina syndrome and planned for surgical excision. His radiological impression was IDEM possibly neurofibroma. To our surprise, we found multiple intradural cystic lesions with arachnoiditis. Dissecting in plane cyst was flushed out, and surgical cavity was irrigated with 3% saline. Postoperatively histopathology and serum tests confirmed the diagnosis of hydatid cyst. Hydatid disease is rare cause of cauda equine syndrome which can be miss diagnosed on radiological investigations. A high index of suspicion should be kept especially in a young patient from the Indian subcontinent. PMID:27891041
Clinical Application of 3D-CISS MRI Sequences for Diagnosis and Surgical Planning of Spinal Arachnoid Diverticula and Adhesions in Dogs.
Tauro, Anna; Jovanovik, Jelena; Driver, Colin John; Rusbridge, Clare
Abnormalities within the spinal arachnoid space are often treated surgically, but they can be challenging to detect with conventional magnetic resonance imaging (MRI) sequences. 3D-CISS sequences are considered superior in evaluating structures surrounded by cerebrospinal fluid (CSF) due to the high signal-to-noise ratio, high contrast-to-noise ratio and intrinsic insensitivity to motion with minimal signal loss due to CSF pulsations. Our objective was to describe findings and advantages in adding 3D-CISS sequences to routine MRI in patients affected by spinal arachnoid diverticula (SAD) or arachnoid adhesions. This article is a retrospective review of medical records of 19 dogs admitted at Fitzpatrick Referrals between 2013 and 2017 that were diagnosed with SAD and confirmed surgically. Inclusion criterions were the presence of clinical signs compatible with compressive myelopathy and an MRI diagnosis, which included the 3D-CISS sequence. Our database was searched for additional 19 dogs diagnosed with other spinal lesions other than SAD that had the same MR sequences. All MR images were anonymized and evaluated by two assessors. 3D-CISS sequence appears to improve confidence in diagnosing and surgical planning (Mann-Whitney U -test: p < 0.0005), delineating SAD from other changes associated with abnormal CSF hydrodynamics and providing more anatomical details than conventional MRI sequences. The clinical data in combination with imaging findings would limit over interpretation, when concurrent pathology within the arachnoid space is present. Schattauer GmbH Stuttgart.
Sports participation with arachnoid cysts.
Strahle, Jennifer; Selzer, Béla J; Geh, Ndi; Srinivasan, Dushyanth; Strahle, MaryKathryn; Martinez-Sosa, Meleine; Muraszko, Karin M; Garton, Hugh J L; Maher, Cormac O
OBJECT There is currently no consensus on the safety of sports participation for patients with an intracranial arachnoid cyst (AC). The authors' goal was to define the risk of sports participation for children with this imaging finding. METHODS A survey was prospectively administered to 185 patients with ACs during a 46-month period at a single institution. Cyst size and location, treatment, sports participation, and any injuries were recorded. Eighty patients completed at least 1 subsequent survey following their initial entry into the registry, and these patients were included in a prospective registry with a mean prospective follow-up interval of 15.9 ± 8.8 months. RESULTS A total 112 patients with ACs participated in 261 sports for a cumulative duration of 4410 months or 1470 seasons. Of these, 94 patients participated in 190 contact sports for a cumulative duration of 2818 months or 939 seasons. There were no serious or catastrophic neurological injuries. Two patients presented with symptomatic subdural hygromas following minor sports injuries. In the prospective cohort, there were no neurological injuries CONCLUSIONS Permanent or catastrophic neurological injuries are very unusual in AC patients who participate in athletic activities. In most cases, sports participation by these patients is safe.
Exploring predictors of surgery and comparing operative treatment approaches for pediatric intracranial arachnoid cysts: a case series of 83 patients.
Ali, Mohsin; Bennardo, Michael; Almenawer, Saleh A; Zagzoog, Nirmeen; Smith, Alston A; Dao, Dyda; Ajani, Olufemi; Farrokhyar, Forough; Singh, Sheila K
Although intracranial arachnoid cysts are a common incidental finding on pediatric brain imaging, only a subset of patients require surgery for them. For the minority who undergo surgery, the comparative effectiveness of various surgical approaches is debated. The authors explored predictors of surgery and compared operative techniques for pediatric patients with an intracranial arachnoid cyst seen at a tertiary care center. The authors reviewed records of pediatric patients with an intracranial arachnoid cyst. For each patient, data on baseline characteristics, the method of intervention, and surgical outcomes for the initial surgery were extracted, and cyst size at diagnosis was calculated (anteroposterior × craniocaudal × mediolateral). Baseline variables were analyzed as predictors of surgery by using logistic regression modeling, excluding patients whose surgery was not related to cyst size (i.e., those with obstructive hydrocephalus secondary to the cyst compressing a narrow CSF flow pathway or cyst rupture/hemorrhage). Data collected regarding surgical outcomes were analyzed descriptively. Among 83 pediatric patients with an intracranial arachnoid cyst seen over a 25-year period (1989-2013), 27 (33%) underwent surgery; all had at least 1 cyst-attributed symptom/finding. In the multivariate model, age at presentation and cyst size at diagnosis were independent predictors of surgery. Cyst size had greater predictive value; specifically, the area under the curve for the receiver-operating-characteristic curve was 0.89 (95% CI 0.82-0.97), with an ideal cutoff point of ≥ 68 cm(3). This cutoff point had 100% sensitivity (95% CI 79%-100%), 75% specificity (95% CI 61%-85%), a 53% positive predictive value (95% CI 36%-70%), and a 100% negative predictive value (95% CI 91%-100%); the positive likelihood ratio was 4.0 (95% CI 2.5-6.3), and the negative likelihood ratio was 0 (95% CI 0-0.3). Although the multivariate model excluded 7 patients who underwent surgery
Spinal Arachnoid Diverticula: Outcome in 96 Medically or Surgically Treated Dogs.
Mauler, D A; De Decker, S; De Risio, L; Volk, H A; Dennis, R; Gielen, I; Van der Vekens, E; Goethals, K; Van Ham, L
Little is reported about the role of medical management in the treatment of spinal arachnoid diverticula (SAD) in dogs. To describe the outcome of 96 dogs treated medically or surgically for SAD. Ninety-six dogs with SAD. Retrospective case series. Medical records were searched for spinal arachnoid diverticula and all dogs with information on treatment were included. Outcome was assessed with a standardized questionnaire. Fifty dogs were managed medically and 46 dogs were treated surgically. Dogs that underwent surgery were significantly younger than dogs that received medical management. No other variables, related to clinical presentation, were significantly different between both groups of dogs. The median follow-up time was 16 months (1-90 months) in the medically treated and 23 months (1-94 months) in the surgically treated group. Of the 38 dogs treated surgically with available long-term follow-up, 82% (n = 31) improved, 3% (n = 1) remained stable and 16% (n = 6) deteriorated after surgery. Of the 37 dogs treated medically with available long-term follow-up, 30% (n = 11) improved, 30% (n = 11) remained stable, and 40% (n = 15) deteriorated. Surgical treatment was more often associated with clinical improvement compared to medical management (P = .0002). The results of this study suggest that surgical treatment might be superior to medical treatment in the management of SAD in dogs. Further studies with standardized patient care are warranted. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.
[Clinical presentation of a dorsal epidural arachnoid cyst after an epidural anesthesia].
Obil-Chavarría, Claudia Alejandra; García-Ramos, Carla Lisette; Castro-Quiñonez, Sergio Alberto; Huato-Reyes, Raúl; Santillán-Chapa, Concepción Guadalupe; Reyes-Sánchez, Alejandro Antonio
Arachnoid cysts are dural diverticula with liquid content similar to cerebrospinal fluid, with 1% occurring in the spinal cord. They locate mainly in the dorsal region of the thoracic spine, and are unusual causes of spinal cord compression. The case is presented of a previously healthy 15-year-old boy, with a 20-month history of spastic paraparesis that started apparently after epidural block for ankle osteosynthesis. There was decreased sensitivity and strength of the pelvic limbs and gradually presented with anaesthesia from T12 to L4 dermatomes, L5 and S1 bilateral hypoaesthesia and 4+/5 bilateral strength, in the L2 root and 2+/5 in L3, L4, L5, S1, hyperreflexia, Babinski and clonus, but with no alteration in the sacral reflexes. In the magnetic resonance it was diagnosed as an extradural arachnoid cyst from T6 to T9. The patient underwent a T6 to T10 laminotomy, cyst resection, dural defect suture, and laminoplasty. One year after surgery, the patient had recovered sensitivity, improvement of muscle strength up to 4+/5 in L2 to S1, and normal reflexes. After the anaesthetic procedure, increased pressure and volume changes within the cyst could cause compression of the spinal cord, leading to symptoms. Despite being a long-term compression, the patient showed noticeable improvement. Copyright © 2015 Academia Mexicana de Cirugía A.C. Publicado por Masson Doyma México S.A. All rights reserved.
Adhesive arachnoiditis after percutaneous fibrin glue treatment of a sacral meningeal cyst.
Hayashi, Kazunori; Nagano, Junji; Hattori, Satoshi
The authors present the case of a 64-year-old woman who was referred for severe sacral pain. She reported that her pain had been longstanding, and had greatly increased after percutaneous fibrin glue placement therapy for a sacral meningeal cyst 2 months earlier at a different hospital. An MRI scan obtained immediately after fibrin glue placement at that hospital suggested that fibrin glue had migrated superiorly into the subarachnoid space from the sacral cyst to the level of L-4. On admission to the authors' institution, physical examination demonstrated no abnormal findings except for perianal hypesthesia. An MRI study obtained at admission demonstrated a cystic lesion in the peridural space from the level of S-2 to S-4. Inhomogeneous intensity was identified in this region on T2-weighted images. Because the cauda equina and nerve roots appeared to be compressed by the lesion, total cyst excision was performed. The cyst cavity was filled with fluid that resembled CSF, plus gelatinous material. Histopathological examination revealed that the cyst wall was composed of hyaline connective tissue with some calcification. No nervous tissue or ganglion cells were found in the tissue. The gelatinous material was acellular, and appeared to be degenerated fibrin glue. Sacral pain persisted to some extent after surgery. The authors presumed that migrated fibrin glue caused the development of adhesive arachnoiditis. The risk of adhesive arachnoiditis should be considered when this therapy is planned. Communication between a cyst and the subarachnoid space should be confirmed to be sufficiently narrow to prevent the migration of injected fibrin glue.
The treatment of large supratentorial arachnoid cysts in infants with cyst-peritoneal shunting and Hakim programmable valve.
Germanò, Antonino; Caruso, Gerardo; Caffo, Mariella; Baldari, Sergio; Calisto, Amedeo; Meli, Francesco; Tomasello, Francesco
This retrospective case series examines 7 infants with large supratentorial arachnoid cysts who underwent cyst-peritoneal shunting and insertion of a Hakim programmable valve. Comparing pre- and postoperative clinical data, neuroradiological and regional cerebral blood flow (rCBF) findings we evaluated the efficacy of the surgical procedure. Infants, ranging in age from 1 to 55 days (mean age 29.5 days), were assessed pre- and postoperatively by neurological examination, developmental profile and neuroimaging. Post procedure, all patients showed a significant reduction in the cyst/brain ratio on neuroimaging (p<0.001), 6 had a normal developmental profile (p<0.001) and 5 cases showed a significant amelioration of clinical symptoms and neurological signs. Two patients underwent preoperative SPECT scans, which showed hypoperfusion in the area surrounding the cyst; this decreased rCBF also improved post shunting. Large supratentorial arachnoid cysts in infants can be successfully treated with cyst-peritoneal shunting and insertion of a Hakim programmable valve. This is the first study specifically aimed at evaluating the long-term results of these conditions.
Sacral extradural arachnoid cyst in association with split cord malformation.
Habibi, Zohreh; Hanaei, Sara; Nejat, Farideh
Split cord malformation (SCM) is a congenital disease that can be associated with other spinal anomalies. Few cases of concurrent intradural arachnoid cyst and SCM have been sporadically reported; however, sacral extradural arachnoid cyst (SEAC) with SCM is very rare. The report describes our experience with simultaneous surgery in patients with concurrent SEAC and SCM in an effort to document the treatment of the rare spinal concomitant anomalies. The present study is designed as a case series. This is a continuous series of patients with coexisting SCM and SEAC who were presented to our institution. The lower extremities weakness and deformity, radiological imaging, urodynamic tests, and surgical aspects of the patient population are documented. Cases with concomitant anomalies were consecutively enrolled among 73 patients who were operated on for SCM between 2008 and 2014. Clinical data and surgical findings were prospectively filed and retrospectively evaluated. There were seven patients (2 boys and 5 girls), with age ranging from 18 to 119 months (mean: 56.71±39.49). Type I SCM was detected in six cases, and type II SCM was detected in one case. Tethering of the cord was detected in all seven patients, and six patients (85.7%) had syrinx formation rostral to the level of SCM. All patients had at least one kind of urological dysfunctions manifesting as neurogenic bladder. On surgery, fistulous orifice of the meningeal cyst was found and ligated in six cases, and the other one was repaired via sealing the cyst walls as near as possible to the thecal sac. In patients with symptomatic SCM, the signs of concurrent SEAC may be masqueraded by the former condition. It would be impossible to attribute a given sign, particularly urological signs, to either SCM or SEAC. Whatever the sign and nature, both conditions are better to be managed surgically in one session under a single anesthesia to prevent duplicate complications of further anesthesia and interventions in
Nerve crush but not displacement-induced stretch of the intra-arachnoidal facial nerve promotes facial palsy after cerebellopontine angle surgery.
Bendella, Habib; Brackmann, Derald E; Goldbrunner, Roland; Angelov, Doychin N
Little is known about the reasons for occurrence of facial nerve palsy after removal of cerebellopontine angle tumors. Since the intra-arachnoidal portion of the facial nerve is considered to be so vulnerable that even the slightest tension or pinch may result in ruptured axons, we tested whether a graded stretch or controlled crush would affect the postoperative motor performance of the facial (vibrissal) muscle in rats. Thirty Wistar rats, divided into five groups (one with intact controls and four with facial nerve lesions), were used. Under inhalation anesthesia, the occipital squama was opened, the cerebellum gently retracted to the left, and the intra-arachnoidal segment of the right facial nerve exposed. A mechanical displacement of the brainstem with 1 or 3 mm toward the midline or an electromagnet-controlled crush of the facial nerve with a tweezers at a closure velocity of 50 and 100 mm/s was applied. On the next day, whisking motor performance was determined by video-based motion analysis. Even the larger (with 3 mm) mechanical displacement of the brainstem had no harmful effect: The amplitude of the vibrissal whisks was in the normal range of 50°-60°. On the other hand, even the light nerve crush (50 mm/s) injured the facial nerve and resulted in paralyzed vibrissal muscles (amplitude of 10°-15°). We conclude that, contrary to the generally acknowledged assumptions, it is the nerve crush but not the displacement-induced stretching of the intra-arachnoidal facial trunk that promotes facial palsy after cerebellopontine angle surgery in rats.
Comparative analysis of bleeding risk by the location and shape of arachnoid cysts: a finite element model analysis.
Lee, Chang-Hyun; Han, In Seok; Lee, Ji Yeoun; Phi, Ji Hoon; Kim, Seung-Ki; Kim, Young-Eun; Wang, Kyu-Chang
Although arachnoid cysts (ACs) are observed in various locations, only sylvian ACs are mainly regarded to be associated with bleeding. The reason for this selective association of sylvian ACs with bleeding is not understood well. This study is to investigate the effect of the location and shape of ACs on the risk of bleeding. A developed finite element model of the head/brain was modified for models of sylvian, suprasellar, and posterior fossa ACs. A spherical AC was placed at each location to compare the effect of AC location. Bowl-shaped and oval-shaped AC models were developed to compare the effect by shape. The shear force on the spot-weld elements (SFSW) was measured between the dura and the outer wall of the ACs or the comparable arachnoid membrane in the normal model. All AC models revealed higher SFSW than comparable normal models. By location, sylvian AC displayed the highest SFSW for frontal and lateral impacts. By shape, small outer wall AC models showed higher SFSW than large wall models in sylvian area and lower SFSW than large ones in posterior fossa. In regression analysis, the presence of AC was the only independent risk of bleeding. The bleeding mechanism of ACs is very complex, and the risk quantification failed to show a significant role of location and shape of ACs. The presence of AC increases shear force on impact condition and may be a risk factor of bleeding, and sylvian location of AC may not have additive risks of AC bleeding.
Limited remyelination of CNS axons by Schwann cells transplanted into the sub-arachnoid space.
Blakemore, W F
Areas of primary demyelination which did not subsequently remyelinate spontaneously were prepared in the cat spinal cord by injecting small volumes of ethidium bromide into tissue which had previously been exposed to 40 Grays of X-irradiation. Autologous peripheral nerve tissue was placed in the sub-arachnoid space over such lesions, either at the time of injecting ethidium bromide, or at 14 days or 28 days after injecting ethidium bromide. The extent of Schwann cell remyelination was assessed 28 days after transplantation. In no case were all the demyelinated axons remyelinated; rather, remyelination was limited to axons near to blood vessels. It was concluded that Schwann cells migrated from the transplanted tissue into the lesion via the perivascular space and that they failed to remyelinate the bulk of demyelinated axons because of an absence within the CNS of suitable extracellular matrix.
Differentiation of idiopathic spinal cord herniation from dorsal arachnoid webs on MRI and CT myelography.
Schultz, Randall; Steven, Andrew; Wessell, Aaron; Fischbein, Nancy; Sansur, Charles A; Gandhi, Dheeraj; Ibrahimi, David; Raghavan, Prashant
OBJECTIVE Dorsal arachnoid webs (DAWs) and spinal cord herniation (SCH) are uncommon abnormalities affecting the thoracic spinal cord that can result in syringomyelia and significant neurological morbidity if left untreated. Differentiating these 2 entities on the basis of clinical presentation and radiological findings remains challenging but is of vital importance in planning a surgical approach. The authors examined the differences between DAWs and idiopathic SCH on MRI and CT myelography to improve diagnostic confidence prior to surgery. METHODS Review of the picture archiving and communication system (PACS) database between 2005 and 2015 identified 6 patients with DAW and 5 with SCH. Clinical data including demographic information, presenting symptoms and neurological signs, and surgical reports were collected from the electronic medical records. Ten of the 11 patients underwent MRI. CT myelography was performed in 3 patients with DAW and in 1 patient with SCH. Imaging studies were analyzed by 2 board-certified neuroradiologists for the following features: 1) location of the deformity; 2) presence or absence of cord signal abnormality or syringomyelia; 3) visible arachnoid web; 4) presence of a dural defect; 5) nature of dorsal cord indentation (abrupt "scalpel sign" vs "C"-shaped); 6) focal ventral cord kink; 7) presence of the nuclear trail sign (endplate irregularity, sclerosis, and/or disc-space calcification that could suggest a migratory path of a herniated disc); and 8) visualization of a complete plane of CSF ventral to the deformity. RESULTS The scalpel sign was positive in all patients with DAW. The dorsal indentation was C-shaped in 5 of 6 patients with SCH. The ventral subarachnoid space was preserved in all patients with DAW and interrupted in cases of SCH. In no patient was a web or a dural defect identified. CONCLUSIONS DAW and SCH can be reliably distinguished on imaging by scrutinizing the nature of the dorsal indentation and the integrity of
Unexplained apnoea and loss of consciousness during sub arachnoid block for caesarean section.
Acharya, S P; Marhatta, M N; Amatya, R
Sub arachnoid block (SAB) is often perceived safe by many anesthesiologists and other faculties but is also not completely safe choice especially in pregnant females, as the incidence of complications and local anaesthetic agent toxicity is high in these groups of patients. Here we present four such cases out of the seventeen patients over a period of six months, who developed apnea and transient loss of consciousness after spinal anesthesia for lower segment caesarean section. Typically all these patients after spinal anesthesia developed difficulty in breathing, became apnoea and had loss of consciousness for about a minute or two. The apnea was relieved with bag and mask ventilation following which the patient regained consciousness and start breathing normally. The rest of the procedure was uneventful. We presented these cases with aim of sharing similar experiences, and to aware about the possibility of such events as these events do occur frequently but case reports and literatures are unavailable.
The dysraphic state of the posterior fossa. Clinical review of the Dandy-Walker syndrome and the so-called arachnoid cysts.
Carteri, A; Gerosa, M; Gaini, S M; Villani, R
The Authors report their case material concerning some basic items of the dysraphic pathology of the Posterior Fossa: 22 cases of Dandy Walker syndromes (DWS) and "Arachnoid Cysts" (PFC). The mean clinical findings (predominant involvement of the vestibular structures of the brain stem in the DWS, frequent epileptic seizures and some cases of hypothalamic disturbances in the PFC) are discussed in the light of current embryological theories on Weed's "area membranacea". Finally the results of differential surgical treatments are examined: good or satisfactory results were obtained with shunts, while still debatable seems to be the direct surgical approach.
Sport-related structural brain injury associated with arachnoid cysts: a systematic review and quantitative analysis.
Zuckerman, Scott L; Prather, Colin T; Yengo-Kahn, Aaron M; Solomon, Gary S; Sills, Allen K; Bonfield, Christopher M
OBJECTIVE Arachnoid cysts (ACs) are congenital lesions bordered by an arachnoid membrane. Researchers have postulated that individuals with an AC demonstrate a higher rate of structural brain injury after trauma. Given the potential neurological consequences of a structural brain injury requiring neurosurgical intervention, the authors sought to perform a systematic review of sport-related structural-brain injury associated with ACs with a corresponding quantitative analysis. METHODS Titles and abstracts were searched systematically across the following databases: PubMed, Embase, CINAHL, and PsycINFO. The review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Peer-reviewed case reports, case series, or observational studies that reported a structural brain injury due to a sport or recreational activity (hereafter referred to as sport-related) with an associated AC were included. Patients were excluded if they did not have an AC, suffered a concussion without structural brain injury, or sustained the injury during a non-sport-related activity (e.g., fall, motor vehicle collision). Descriptive statistical analysis and time to presentation data were summarized. Univariate logistic regression models to assess predictors of neurological deficit, open craniotomy, and cystoperitoneal shunt were completed. RESULTS After an initial search of 994 original articles, 52 studies were found that reported 65 cases of sport-related structural brain injury associated with an AC. The median age at presentation was 16 years (range 4-75 years). Headache was the most common presenting symptom (98%), followed by nausea and vomiting in 49%. Thirteen patients (21%) presented with a neurological deficit, most commonly hemiparesis. Open craniotomy was the most common form of treatment (49%). Bur holes and cyst fenestration were performed in 29 (45%) and 31 (48%) patients, respectively. Seven patients (11%) received
A screening method to distinguish syndromic from sporadic spinal extradural arachnoid cyst.
Ogura, Yoji; Yabuki, Shoji; Fujibayashi, Shunsuke; Okada, Eijiro; Iwanami, Akio; Watanabe, Kota; Nakamura, Masaya; Matsumoto, Morio; Ishii, Ken; Ikegawa, Shiro
Spinal extradural arachnoid cyst (SEDAC) is a cystic lesion that protrudes into the epidural space from a small dural defect. Early diagnosis of SEDAC is important because its expansion causes neurological damage. Two types of SEDAC, syndromic and sporadic, are present. Syndromic SEDAC is inherited as a part of lymphedema-distichiasis syndrome caused by mutations in the FOXC2 gene; however, it is often mistaken as sporadic because of low penetrance. It is not reasonable to conduct a genetic testing for all SEDAC patients and their family members. The aim of this study is to establish an effective screening method to distinguish syndromic SEDAC from sporadic SEDAC. We performed a retrospective review of medical records and imaging studies of 29 subjects who were diagnosed with SEDAC. Clinical features, family history and magnetic resonance imaging (MRI) were analyzed. Mutations in FOXC2 were examined by Sanger-sequencing of the entire coding region of the genes. SEDAC having a mutation in FOXC2 gene was defined with syndromic SEDAC. Eleven subjects had a heterozygous mutation in FOXC2. They were all familial and hence syndromic SEDAC. Only one proband had known family history of SEDAC at diagnosis. MRI findings and physical examinations, especially eye and leg examinations, were quite useful to screen syndromic SEDAC. Physical examination often showed accompanying lymphedema and distichiasis in syndromic SEDAC. Syndromic SEDAC tended to have multiple cysts out of the thoracolumbar area. We established an effective screening method based on physical examinations and MRI findings. Copyright © 2018 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.
Spinal arachnoid cysts in the pediatric population: report of 31 cases and a review of the literature.
Bond, Aaron E; Zada, Gabriel; Bowen, Ira; McComb, J Gordon; Krieger, Mark D
The goal of this study was to review all cases of pediatric spinal arachnoid cysts (SACs) surgically treated at the authors' institution between 1992 and 2008 and to compare these cases to the published literature for the general population. The charts of all pediatric patients with SACs were reviewed for demographics, medical history, presenting symptoms, imaging findings, operative procedure(s), complications, and outcomes. Following a complete literature review, the pediatric data were compared with data from the general population and unique findings associated with pediatric patients were identified. Thirty-one pediatric patients (median age 6.9 years) underwent operative intervention for SACs between 1992 and 2008 (median duration of follow-up 4.2 years). There were 17 female patients (55%) and 14 male patients (45%). Twenty-one patients (68%) presented with symptoms of radiculopathy or myelopathy. The most common presenting symptoms were pain (42%), lower-extremity weakness (39%), gait instability (32%), spasticity (19%), sensory loss (10%), and bladder dysfunction (7%). In 3 patients (10%) SACs were incidental findings. Intradural SACs were more common (18 patients, 58%) than extradural SACs (11 patients, 36%). One patient (3%) had extradural and intradural components. One patient (3%) had a purely intramedullary cyst, and 1 patient (3%) had both an intradural and intramedullary component. Of the 18 intradural SACs, 9 (50%) were located ventral to the spinal cord and 9 (50%) were dorsally situated. One dorsal intradural SAC had an intramedullary component. All extradural SACs were located dorsal to the spinal cord. Intradural SACs were primarily concentrated in the cervical and thoracic regions (67%), whereas extradural cysts were more evenly distributed between the thoracic, lumbar, and sacral regions. Of the 18 patients with intradural SACs, 13 (72%) had significant previous CNS abnormalities, compared with 3 (27%) of 11 patients with extradural SACs
Analysis on clinical characteristics of intracranial Arachnoid Cysts in 488 pediatric cases
Huang, Jian-Huang; Mei, Wen-Zhong; Chen, Yao; Chen, Jian-Wu; Lin, Zhi-Xiong
To summarize the clinical characteristics of intracranial arachnoid cysts (IACs) in pediatric cases. A retrospective analysis was carried out on clinical characteristics of IACs in 488 pediatric cases who were treated at our hospital from January 2003 to September 2013. There were 342 males and 146 females (male-to-female ratio, 2.34:1), aged 5.61±3.25 years on average. 221 cases (45.29%) were diagnosed accidentally, 267 cases had clinical complaints (54.71%), among which relationships between clinical complaints and IACs were identified in 123 (46.07%). Simple IACs occurred in 364 cases (4.59%), and concurrent congenital abnormalities occurred in 124 cases (4.59%). In terms of location, 355 had IACs in middle cranial fossa (72.75%), 82 cases in posterior cranial fossa (16.80%), 20 cases in anterior cranial fossa (4.10%), 12 cases in dorsolateral surface (2.46%), 7 cases in suprasellar cistern (1.43%), 5 cases in cerebral ventricle (1.02%), 5 cases in quadrigeminal cistern (1.02%), and 2 cases in interhemispheric region (0.41%). There were 449 cases with single IAC (92.01%) and 39 cases with multiple IACs (7.99%). On MRI, the cysts produced tension in 127 cases (26.02%), but not in the remaining 361 cases (73.98%). Surgery was performed on 76 of 488 cases (15.57%), while conservative observation was accepted in 412 cases (84.43%). For the former, the symptoms and the cyst volume were improved to varying extent; for the latter, the follow-up lasting for 3-72 months (average 32.43±8.92 months) showed that the cyst volume remained stable in 407 cases (98.78%), enlarged with aggravated symptoms in 3 cases (0.73%), and shrank in 2 cases (0.49%). Clinical complaints of IACs varied in pediatric cases, and the relationships between clinical complaints and IACs were established only partially. Some pediatric cases were combined with other congenital abnormalities. The cyst volume largely remained stable during the disease course, and surgery was required for only a few
Predictors and outcomes of shunt-dependent hydrocephalus in patients with aneurysmal sub-arachnoid hemorrhage
Background Hydrocephalus following spontaneous aneurysmal sub-arachnoid hemorrhage (SAH) is often associated with unfavorable outcome. This study aimed to determine the potential risk factors and outcomes of shunt-dependent hydrocephalus in aneurysmal SAH patients but without hydrocephalus upon arrival at the hospital. Methods One hundred and sixty-eight aneurysmal SAH patients were evaluated. Using functional scores, those without hydrocephalus upon arrival at the hospital were compared to those already with hydrocephalus on admission, those who developed it during hospitalization, and those who did not develop it throughout their hospital stay. The Glasgow Coma Score, modified Fisher SAH grade, and World Federation of Neurosurgical Societies grade were determined at the emergency room. Therapeutic outcomes immediately after discharge and 18 months after were assessed using the Glasgow Outcome Score. Results Hydrocephalus accounted for 61.9% (104/168) of all episodes, including 82 with initial hydrocephalus on admission and 22 with subsequent hydrocephalus. Both the presence of intra-ventricular hemorrhage on admission and post-operative intra-cerebral hemorrhage were independently associated with shunt-dependent hydrocephalus in patients without hydrocephalus on admission. After a minimum 1.5 years of follow-up, the mean Glasgow outcome score was 3.33 ± 1.40 for patients with shunt-dependent hydrocephalus and 4.21 ± 1.19 for those without. Conclusions The presence of intra-ventricular hemorrhage, lower mean Glasgow Coma Scale score, and higher mean scores of the modified Fisher SAH and World Federation of Neurosurgical grading on admission imply risk of shunt-dependent hydrocephalus in patients without initial hydrocephalus. These patients have worse short- and long-term outcomes and longer hospitalization. PMID:22765765
[Left temporal arachnoid cyst and specific learning disorders associated with Pervasive Developmental Disorders - Not Otherwise Specified (PDD-NOS): contributions of an integrative neuropsychomotor, neuropsychological, psychopathological and neurosurgical approach about a case report in a child (François)].
Vaivre-Douret, L; Boschi, A; Cuny, M L; Clouard, C; Mosser, A; Golse, B; Philippe, A; Bourgeois, M; Boddaert, N; Puget, S
Left temporal arachnoid cyst and specific learning disorders associated with pervasive developmental disorders - not otherwise specified (PDD-NOS): contributions of an integrative neuro-psychomotor, neuropsychological, psychopathological and neurosurgical approach about a case report in a child (François). With DSM-IV and DSM-IV-TR, the terminology of pervasive developmental disorders (PDD) covers two main categories of infantile disorders: disorders of "strictly" autistic nature and pervasive developmental disorders - not otherwise specified (PDD-NOS). Under the terminology of multiple complex developmental disorder (MCDD), it is proposed to classify children presenting symptoms approaching the psychotic disharmonies and usually diagnosed as PDD-NOS. Such a category of developmental disorders is now included without nosographic distinction in the autistic spectrum in the Diagnostic and Statistical Manual of mental disorders (DSM-V). We are reporting a case report of a 6-year-old boy which shows a PDD-NoS/MCDD complex symptomatology type. This child presents multiple disorders: minor neurological signs (soft signs), neuro-psychomotor disorders, developmental coordination disorder (DCD), communication, thought, and regulation of emotions disorders, attention deficit disorders (ADD); in the presence of a high verbal intellectual potential, which makes it difficult to establish a clear diagnosis. A cerebral magnetic resonance imaging (MRI) was carried out due to the presence of minor neurological signs (soft signs) and of neurodevelopmental multiple disorders. The MRI revealed a voluminous arachnoid temporo-polar left cyst with a marked mass effect on the left temporal lobe. A neurosurgical intervention allowed to observe the gradual disappearance of the specific symptomatology (in particular soft signs, neuro-psychomotor functions and autistic symptoms) secondary to the interference of the cyst's pressure with intracranial areas involving neurological and
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Reversible dyscognition in patients with a unilateral, middle fossa arachnoid cyst revealed by using a laptop based neuropsychological test battery (CANTAB).
Torgersen, Johan; Helland, Christian; Flaatten, Hans; Wester, Knut
The aim of this study was to evaluate and validate the Cambridge Neuropsychological Test Automated Battery (CANTAB) in a Norwegian group of patients undergoing surgery for middle fossa arachnoid cysts (AC). We also wanted to assess health related quality of life (HRQOL) in these patients to see if it could be improved by decompression of the AC. Adult patients (>18 years) with unilateral middle fossa AC and no previous history of neurological disease, head injury, or a psychiatric disorder were eligible for inclusion. We used four tests from CANTAB to assess the level of neuropsychological performance: paired associate learning (PAL) and delayed matching to sample (DMS) assessed temporal lobe functions, while Stockings of Cambridge (SOC) and intra-extra dimensional (IED) shift focused on frontal lobe functions. Patients with postoperative cerebral complications were reported, but excluded from neuropsychological follow-up. In addition to the CANTAB data, pre- and postoperative clinical and radiological data were collected. HRQOL was assessed using Short Form 36 (SF-36) pre- and postoperatively. We found significant improvement in the two temporal tests assessing memory, but no improvement in the two frontal tests assessing executive function. HRQOL was significantly reduced preoperatively in two of eight SF-36 domains and improved significantly in four domains postoperatively. CANTAB facilitates detection of cognitive improvements after decompression of the cyst in patients with AC in the middle fossa. The improvements were detected on the tests sensitive to temporal lobe problems only, not on the tests more sensitive to frontal lobe affection. This establishes construct validity for CANTAB for the first time in this population.
Midline cystic malformations of the brain: imaging diagnosis and classification based on embryologic analysis.
Utsunomiya, Hidetsuna; Yamashita, Shinichi; Takano, Koichi; Ueda, Yukiyo; Fujii, Akira
This article describes a classification and imaging diagnosis of intracranial midline cystic malformations based on neuroembryologic analysis. Midline cystic malformations are classified into two categories from an embryologic point of view. In one category, the cyst represents expansion of the roof plate of the brain vesicle, and in the other the cyst consists of extraaxial structures such as an arachnoid membrane or migrating ependymal cells. Infratentorial cysts, such as the Dandy-Walker cyst or Blake's pouch cyst, and supratentorial cysts, such as a communicating interhemispheric cyst with callosal agenesis or a dorsal cyst with holoprosencephaly, are included in the first category. Infratentorial arachnoid cavities, such as the arachnoid cyst, arachnoid pouch, and mega cisterna magna, are in the second category. Noncommunicating interhemispheric cysts, such as interhemispheric arachnoid cyst or ependymal cyst, with callosal agenesis are also in the second category. A careful review of embryologic development is essential for understanding these midline cysts and for making a more accurate radiologic diagnosis.
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Perineurial-like Cells and EMA Expression in the Suprachoroidal Region of the Human Eye.
Gilbert, Andrea R; Chévez-Barrios, Patricia; Cykowski, Matthew D
The suprachoroidal region of the eye comprises vascular channels, melanocytes, and thin fibroblasts with elongated cytoplasm that are positioned directly adjacent to the densely collagenous sclera. Morphological similarities between these suprachoroidal fibroblasts and arachnoid cells and perineurial cells have been recognized, but whether these fibroblasts have a perineurial cell-like immunophenotype is not known. To further examine the relationship of these three cell types, we investigated the comparative expression of epithelial membrane antigen (EMA), the tight junction protein claudin-1, glucose transporter-1 (Glut-1), and CD34 in suprachoroidal fibroblasts, arachnoid of the optic nerve sheath, and perineurium of ciliary nerves in eight human eye specimens. Granular, diffuse, and cytoplasmic EMA expression was seen in suprachoroidal fibroblasts, but this was not contiguous with the similar pattern of EMA expression in adjacent perineurium and arachnoid. CD34 expression in suprachoroidal fibroblasts was also seen, similar to arachnoid and perineurium. Claudin-1 and Glut-1 were not consistently expressed in suprachoroidal fibroblasts, distinguishing them from perineurial cells in particular and suggesting that these fibroblasts do not arise directly from adjacent arachnoid or perineurium. Nonetheless, the overlapping morphology and protein expression suggest phenotypic similarities in these cells that protect and support adjacent retina, optic nerve, and peripheral nerve.
New Methods of Low-Field Magnetic Resonance Imaging for Application to Traumatic Brain Injury
Subdural hemor- rhage (or hematoma ) is a form of traumatic brain injury, in which blood gathers between the du- ra and arachnoid mater (in meningeal...to an hour. Subdural hemorrhage (or hematoma ) is a form of traumatic brain injury, in which blood gathers between the dura and arachnoid mater (in
A migratory mantle plume on Venus: Implications for Earth?
Chapman, M.G.; Kirk, R.L.
A spatially fixed or at least internally rigid hotspot reference frame has been assumed for determining relative plate motions on Earth. Recent 1:5,000,000 scale mapping of Venus, a planet without terrestrial-style plate tectonics and ocean cover, reveals a systematic age and dimensional progression of corona-like arachnoids occurring in an uncinate chain. The nonrandom associations between arachnoids indicate they likely formed from a deep-seated mantle plume in a manner similar to terrestrial hotspot features. However, absence of expected convergent "plate" margin deformation suggests that the arachnoids are the surface expression of a migratory mantle plume beneath a stationary surface. If mantle plumes are not stationary on Venus, what if any are the implications for Earth?
Preoperative Navigated Transcranial Magnetic Stimulation and Tractography to Guide Endoscopic Cystoventriculostomy: A Technical Note and Case Report.
Hendrix, Philipp; Senger, Sebastian; Griessenauer, Christoph J; Simgen, Andreas; Linsler, Stefan; Oertel, Joachim
To report a technique for endoscopic cystoventriculostomy guided by preoperative navigated transcranial magnetic stimulation (nTMS) and tractography in a patient with a large speech eloquent arachnoid cyst. A 74-year old woman presented with a seizure and subsequent persistent anomic aphasia from a progressive left-sided parietal arachnoid cyst. An endoscopic cystoventriculostomy and endoscope-assisted ventricle catheter placement were performed. Surgery was guided by preoperative nTMS and tractography to avoid eloquent language, motor, and visual pathways. Preoperative nTMS motor and language mapping were used to guide tractography of motor and language white matter tracts. The ideal locations of entry point and cystoventriculostomy as well as trajectory for stent-placement were determined preoperatively with a pseudo-3-dimensional model visualizing eloquent language, motor, and visual cortical and subcortical information. The early postoperative course was uneventful. At her 3-month follow-up visit, her language impairments had completely recovered. Additionally, magnetic resonance imaging demonstrated complete collapse of the arachnoid cyst. The combination of nTMS and tractography supports the identification of a safe trajectory for cystoventriculostomy in eloquent arachnoid cysts. Copyright © 2017 Elsevier Inc. All rights reserved.
Evaluation of the Communication Between Arachnoid Cysts and Neighboring Cerebrospinal Fluid Spaces by T2W 3D-SPACE With Variant Flip-Angle Technique at 3 T.
Phase-contrast cine magnetic resonance imaging (PC-MRI) is a widely used technique for determination of possible communication of arachnoid cysts (ACs). Three-dimensional (3D) sampling perfection with application-optimized contrasts using different flip-angle evolutions (3D-SPACE) technique is a relatively new method for 3D isotropic scanning of the entire cranium within a short time. In this research, the usage of the 3D-SPACE technique in differentiation of communicating or noncommunicating type ACs was evaluated. Thirty-five ACs in 34 patients were retrospectively examined. The 3D-SPACE, PC-MRI, and contrast material-enhanced cisternography (if present) images of the patients were analyzed. Each cyst was described according to cyst size/location, third ventricle diameter, Evans index, and presence of hydrocephalus. Communication was defined as absent (score 0), suspected (score 1), or present (score 2) on each sequence. Results of PC-MRI or cisternography (if available) examinations were used as criterion standard techniques to categorize all cysts as communicating or noncommunicating type. The results of 3D-SPACE were compared with criterion standard techniques. The comparisons between groups were performed using Mann-Whitney and Fisher exact tests. For demonstration of communication status of the cysts, criterion standard test results and 3D-SPACE findings were almost in perfect harmony (κ[95% confidence interval: 0.94]; P < 0.001). When evaluating the communicative properties, 3D-SPACE findings correlated with other final results at a rate of 97%. There is a positive correlation with third ventricular diameters and Evans index for all patients (r = 0.77, P < 0.001). For other analyzed variables, there is no significant difference or correlation between the groups. The 3D-SPACE technique is an easy, useful, and noninvasive alternative for the evaluation of morphology, topographical relationships, and communication status of ACs.
Intradural pathology and pathophysiology associated with Chiari I malformation in children and adults with and without syringomyelia.
Dlouhy, Brian J; Dawson, Jeffrey D; Menezes, Arnold H
OBJECTIVE The pathophysiology underlying tonsillar herniation and CSF obstruction in Chiari malformation Type I (CM-I) is unclear, and the cause of CM-I-associated syringomyelia is not well understood. A better understanding of this pathophysiology is important for an improved treatment strategy. Therefore, the authors sought to identify, characterize, and examine the intradural pathology and CSF flow pathophysiology in the posterior fossa and at the level of the foramen magnum that occurs in the setting of CM-I. They determined the incidence of these intradural findings and assessed differences across age, with the degree of tonsillar herniation, and in the presence and absence of syringomyelia. METHODS A prospective database initiated in March 2003 recorded all intraoperative findings during surgical treatment of children and adults with CM-I with or without syringomyelia. A total of 389 surgeries for CM-I were performed in 379 patients between March 2003 and June 2016. A total of 109 surgeries were performed in 109 patients with CM-I (without osseoligamentous abnormalities) in whom both a posterior fossa extradural and intradural decompression with duraplasty was performed (first-time intradural procedures). Using a surgical microscope, intradural pathology and obstruction of CSF channels were identified and assessed. Student t-tests and Fisher's exact tests compared groups in a series of univariate analyses, followed by multivariate logistic regression. RESULTS The following intradural pathological entities were observed (prevalence noted in parentheses). These include those that did not obstruct CSF flow channels: opacified arachnoid (33.0%), thickened arachnoid (3.7%), ischemic and gliotic tonsils (40.4%), tonsillar cysts (0.9%), and inferior descent of the fourth ventricle and cervicomedullary junction (CMJ) (78.0%). The following intradural pathological entities were observed to obstruct CSF flow channels: medialized tonsils (100%), tonsil overlying and
Shunting effects in patients with idiopathic normal pressure hydrocephalus; correlation with cerebral and leptomeningeal biopsy findings.
Bech, R A; Waldemar, G; Gjerris, F; Klinken, L; Juhler, M
Normal Pressure Hydrocephalus (NPH) is a potentially treatable syndrome with abnormal cerebrospinal fluid dynamics. Meningeal fibrosis and/or obliteration of the subarachnoid space have been suggested as one of the patho-anatomical substrates. However, other types of adult onset dementia, predominantly Alzheimer's disease and Vascular Dementia, may mimic the clinical NPH characteristics. The purpose of the present study was to correlate cerebral parenchymal and leptomeningeal biopsy findings to the clinical outcome after CSF shunting in a prospective group of idiopathic NPH (INPH) patients. The study comprises 27 patients with INPH, diagnosed and shunted according to generally accepted clinical, imaging and hydrodynamic criteria. In all patients a frontal leptomeningeal and brain biopsy was obtained prior to the shunt insertion. Degenerative cerebral changes, most often Alzheimer (6 cases) or vascular changes (7 cases) were described in 14 out of 27 biopsies. Arachnoid fibrosis was found in 9 of the 18 biopsies containing arachnoid tissue. Overall, nine patients (33%) improved, of whom 6 presented Alzheimer or vascular changes in their biopsies. No correlation was found between clinical outcome and the presence or absence of degenerative cerebral changes and/or arachnoid fibrosis. However, a tendency towards higher improvement rates was noted in the subgroups presenting degenerative cerebral changes or arachnoid fibrosis. The results suggest that no constant morphological element exists in the syndrome of INPH. Various aetiologies may be involved in the pathogenesis and possibly in some cases co-existing: Patients may also improve by shunting despite the presence of degenerative cerebral parenchymal changes.
Neuroimaging findings in pediatric sports-related concussion.
Ellis, Michael J; Leiter, Jeff; Hall, Thomas; McDonald, Patrick J; Sawyer, Scott; Silver, Norm; Bunge, Martin; Essig, Marco
The goal in this review was to summarize the results of clinical neuroimaging studies performed in patients with sports-related concussion (SRC) who were referred to a multidisciplinar ypediatric concussion program. The authors conducted a retrospective review of medical records and neuroimaging findings for all patients referred to a multidisciplinary pediatric concussion program between September 2013 and July 2014. Inclusion criteria were as follows: 1) age ≤ 19 years; and 2) physician-diagnosed SRC. All patients underwent evaluation and follow-up by the same neurosurgeon. The 2 outcomes examined in this review were the frequency of neuroimaging studies performed in this population (including CT and MRI) and the findings of those studies. Clinical indications for neuroimaging and the impact of neuroimaging findings on clinical decision making were summarized where available. This investigation was approved by the local institutional ethics review board. A total of 151 patients (mean age 14 years, 59% female) were included this study. Overall, 36 patients (24%) underwent neuroimaging studies, the results of which were normal in 78% of cases. Sixteen percent of patients underwent CT imaging; results were normal in 79% of cases. Abnormal CT findings included the following: arachnoid cyst (1 patient), skull fracture (2 patients), suspected intracranial hemorrhage (1 patient), and suspected hemorrhage into an arachnoid cyst (1 patient). Eleven percent of patients underwent MRI; results were normal in 75% of cases. Abnormal MRI findings included the following: intraparenchymal hemorrhage and sylvian fissure arachnoid cyst (1 patient); nonhemorrhagic contusion (1 patient); demyelinating disease (1 patient); and posterior fossa arachnoid cyst, cerebellar volume loss, and nonspecific white matter changes (1 patient). Results of clinical neuroimaging studies are normal in the majority of pediatric patients with SRC. However, in selected cases neuroimaging can provide
Postoperative evaluation for intracranial recurrence of medulloblastoma: MR findings with Gadopentetate dimeglumine
DOE Office of Scientific and Technical Information (OSTI.GOV)
Meyers, S.P.; Wildenhain, S.; Chess, M.A.
Purpose: To characterize the gadopentetate dimeglumine-enhanced MR features of recurrent medulloblastoma. Methods: The postsurgical gadopentetate dimeglumine-enhanced MR images of 48 patients (206 head examinations) with prior resection of medulloblastoma were retrospectively evaluated for enhancement in the brain parenchyma, meninges (dura, pia-arachnoid), and ventricles. Results: Nineteen patients had recurrent tumor as determined by clinical course and positive imaging studies. Seventeen patients with recurrent disease had intracranial enhancement predominating in the pia-arachnoid (63%) or as a focal nodular brain lesion (26%). Three of these patients also had intraventricular metastases. None of the clinically healthy patients had these findings. One patient with recurrentmore » disease had extensive skeletal metastases without involvement of the central nervous system. Dural enhancement was observed in patients both with (42%) and without (38%) recurrent tumor. Conclusion: The MR findings of pia-arachnoidal or focal nodular brain enhancement are highly specific in the diagnosis of recurrent medulloblastoma. Pia-arachnodal or focal nodular brain enhancement were also a reliable indicator of recurrent medulloblastoma. Not all intraventricular metastases enhance with gadopentetate dimeglumine, and careful evaluation for nonenhancing lesions within the ventricles should be made on postoperative MR examines. 27 refs., 11 figs., 1 tab.« less
Atypical cerebellar slump syndrome and external hydrocephalus following craniocervical decompression for Chiari I malformation: case report.
Thakar, Sumit; Dadlani, Ravi; Tawari, Manish; Hegde, Alangar S
Symptomatic cerebellar slump (CS) and external hydrocephalus (EH) are amongst the rarer complications of foramen magnum decompression (FMD) for Chiari I malformation (CM). CS typically presents with delayed onset headache related to dural traction or with neurological deficit offsetting the benefit of FMD. EH, consisting of ventriculomegaly along with subdural fluid collection(s) (SFCs), has been related to cerebrospinal fluid egress from a tiny breach in an otherwise intact arachnoid. We describe the case of a 21-year-old man with CM and syringomyelia who presented with impaired gag, spastic quadriparesis, and raised intracranial pressure 1 week following an uneventful FMD during which the arachnoid had been widely fenestrated. Magnetic resonance imaging (MRI) showed an infratentorial SFC, dilated aqueduct and triventriculomegaly, features of CS, and a residual but resolving syrinx. His symptoms resolved following a high pressure ventriculo-peritoneal shunt. At a 6-month follow-up visit, he was asymptomatic and demonstrated partial resolution of the syrinx, with no recurrence of the SFC. The unusual features in the clinical course of this patient were an atypical CS syndrome presenting with concomitantly resolving syringomyelia, and the development of EH after a wide arachnoidal fenestration. This is the first case in indexed literature describing such a combination of unusual postoperative complications of a FMD. A hypothesis is presented to explain the clinico-radiological findings of the case.
Atypical Cerebellar Slump Syndrome and External Hydrocephalus following Craniocervical Decompression for Chiari I Malformation: Case Report
THAKAR, Sumit; DADLANI, Ravi; TAWARI, Manish; HEGDE, Alangar S
Symptomatic cerebellar slump (CS) and external hydrocephalus (EH) are amongst the rarer complications of foramen magnum decompression (FMD) for Chiari I malformation (CM). CS typically presents with delayed onset headache related to dural traction or with neurological deficit offsetting the benefit of FMD. EH, consisting of ventriculomegaly along with subdural fluid collection(s) (SFCs), has been related to cerebrospinal fluid egress from a tiny breach in an otherwise intact arachnoid. We describe the case of a 21-year-old man with CM and syringomyelia who presented with impaired gag, spastic quadriparesis, and raised intracranial pressure 1 week following an uneventful FMD during which the arachnoid had been widely fenestrated. Magnetic resonance imaging (MRI) showed an infratentorial SFC, dilated aqueduct and triventriculomegaly, features of CS, and a residual but resolving syrinx. His symptoms resolved following a high pressure ventriculo-peritoneal shunt. At a 6-month follow-up visit, he was asymptomatic and demonstrated partial resolution of the syrinx, with no recurrence of the SFC. The unusual features in the clinical course of this patient were an atypical CS syndrome presenting with concomitantly resolving syringomyelia, and the development of EH after a wide arachnoidal fenestration. This is the first case in indexed literature describing such a combination of unusual postoperative complications of a FMD. A hypothesis is presented to explain the clinico-radiological findings of the case. PMID:24257499
HIMALAIA (Hypertension Induction in the Management of AneurysmaL subArachnoid haemorrhage with secondary IschaemiA): a randomized single-blind controlled trial of induced hypertension vs. no induced hypertension in the treatment of delayed cerebral ischemia after subarachnoid hemorrhage.
Gathier, C S; van den Bergh, W M; Slooter, A J C
Delayed cerebral ischemia (DCI) is a major complication after aneurysmal subarachnoid hemorrhage (SAH). One option to treat delayed cerebral ischemia is to use induced hypertension, but its efficacy on the eventual outcome has not been proven in a randomized clinical trial. This article describes the design of the HIMALAIA trial (Hypertension Induction in the Management of AneurysmaL subArachnoid haemorrhage with secondary IschaemiA), designed to assess the effectiveness of induced hypertension on neurological outcome in patients with DCI after SAH. To investigate whether induced hypertension improves the functional outcome in patients with delayed cerebral ischemia after SAH. The HIMALAIA trial is a multicenter, singe-blinded, randomized controlled trial in patients with DCI after a recent SAH. Eligible patients will be randomized to either induced hypertension (n = 120) or to no induced hypertension (n = 120). In selected centers, the efficacy of induced hypertension in augmenting cerebral blood flow will be measured by means of cerebral perfusion computerized tomography scanning. Follow-up assessments will be performed at 3 and 12 months after randomization by trial nurses who are blinded to the treatment allocation and management. We will include patients during five years. The primary outcome is the proportion of subarachnoid hemorrhage patients with delayed cerebral ischemia with poor outcome three-months after randomization, defined as a modified Rankin scale of more than 3. Secondary outcome measures are related to treatment failure, functional outcome, adverse events, and cerebral hemodynamics. The HIMALAIA trial is registered at clinicaltrials.gov under identifier NCT01613235. © 2013 The Authors. International Journal of Stroke © 2013 World Stroke Organization.
Endoscopic Transsphenoidal Cisternostomy for Nonneoplastic Sellar Cysts
Su, Yukai; Ishii, Yudo; Lin, Chien-Min; Tahara, Shigeyuki; Teramoto, Akira; Morita, Akio
Background and Importance. Sellar arachnoid cysts and Rathke's cleft cysts are benign lesions that produce similar symptoms, including optochiasmatic compression, pituitary dysfunction, and headache. Studies have reported the use of various surgical treatment methods for treating these symptoms, preventing recurrence, and minimizing operative complications. However, the postoperative cerebrospinal fluid (CSF) fistula and recurrence rate remain significant. Clinical Presentation. In this paper, we present 8 consecutive cases involving arachnoid cysts and Rathke's cleft cysts, which were managed by using drainage and cisternostomy, the intentional fenestration of the cyst into the subarachnoid space, and then meticulously closing sellar floor using dural sutures. The postoperative images, CSF fistula rate, and the recurrence rate were favorable. Conclusion. We report this technique and discuss the benefit of this minimally invasive approach. PMID:25685785
Non-schwannomatosis lesions of the internal acoustic meatus-a diagnostic challenge and management: a series report of nine cases.
Moura da Silva, Luis Fernando; Buffon, Viviane Aline; Coelho Neto, Maurício; Ramina, Ricardo
Vestibular schwannomas (VS) are the most common lesions of cerebellopontine angle (CPA) corresponding to 76-91 % of the cases. Usually, these lesions present typical CT and MRI findings. Non-schwannomatous tumors restricted to the internal auditory meatus (IAM) are rare and their preoperative radiological diagnosis may be difficult. This article describes nine surgically treated intrameatal non-schwannomatous lesions (NSL) and reviews the literature. In the last 16 years, a total of 471 patients with diagnosis of VS were operated on in our department. Preoperatively, 42 patients had diagnosis of intrameatal schwannomas, but surgery revealed in nine cases NSL (3 meningiomas, 3 arachnoiditis/neuritis, 1 cavernoma, 1 vascular loop, and 1 arachnoid cyst). Most frequent symptoms presented by patients with NSL were hearing loss 89 % (8/9) of patients, tinnitus 78 % (7/9), and vertigo 33 % (3/9). Almost all lesions (8/9) presented MRI findings of isointense signal in T1W with contrast enhancement. The only exception was the arachnoid cyst with intracystic bleeding, which was hyperintense in T1W that is not enhanced with contrast. This series shows an occurrence of 21.4 % of non-schwannomatous tumors in 42 cases of lesions restricted to the IAM. Whenever a solely intrameatal enhanced tumor is detected, it is necessary to think about other diagnostic possibilities rather than VS. Therapeutic management may be changed, specially if radiosurgical treatment is considered.
The spider-like katydid Arachnoscelis (Orthoptera: Tettigoniidae: Listroscelidinae): anatomical study of the genus.
Montealegre-Z, Fernando; Cadena-Castañeda, Oscar J; Chivers, Benedict
This paper provides some observations on the anatomy of the neotropical katydid Arachnoscelis arachnoides Karny (Insecta: Orthoptera: Tettigoniidae). Arachnoscelis is a genus of predaceous katydids that comprise species that resemble spiders in their general body appearance. The type species, A. arachnoids, was described in 1891 from a single male collected in Colombia. Following the original description, these creatures were never found again, and were thought to have gone extinct or mistakenly assigned to the type locality. But between 1891 and 2012 four more species were described and in- correctly assigned to Arachnoscelis based on a similarity of body form. In this paper we present an anatomical comparaison of Arachnoscelis and its relatives, and propose that Arachnoscelis should be treated as a monotypic genus. This implies that other species previously described in Arachnoscelis, should be placed in different genera.
Venusian channels and valleys - Distribution and volcanological implications
NASA Technical Reports Server (NTRS)
Komatsu, Goro; Baker, Victor R.; Gulick, Virginia C.; Parker, Timothy J.
An updated map is presented which shows the distribution of more than 200 channels and valleys on Venus. A large number of channels are concentrated in equatorial regions characterized by highlands, rift and fracture zones, an associated volcanic features. Many channels associated with flow deposits are similar to typical terrestrial lava drainage channels. They are associated with a wide range of volcanic edifices. More than half of the sinuous rilles are associated with coronae, coronalike features, or arachnoids. Corona volcanism driven by mantle plume events may explain this association. Many valley network are observed in highlands and in association with coronae, coronalike features, or arachnoids. This indicates that highlands and coronae provided fractures and flow-viscosity lavas, both of which seem to be required for network formation by lava sapping processes. Canali-type channels have a unique distribution limited to some plains regions.
Ocular Manifestations of Oblique Facial Clefts
Ortube, Maria Carolina; Dipple, Katrina; Setoguchi, Yoshio; Kawamoto, Henry K.; Demer, Joseph L.
Introduction In the Tessier classification, craniofacial clefts are numbered from 0 to 14 and extend along constant axes through the eyebrows, eyelids, maxilla, nostrils, and the lips. We studied a patient with bilateral cleft 10 associated with ocular abnormalities. Method Clinical report with orbital and cranial computed tomography. Results After pregnancy complicated by oligohydramnios, digoxin, and lisinopril exposure, a boy was born with facial and ocular dysmorphism. Examination at age 26 months showed bilateral epibulbar dermoids, covering half the corneal surface, and unilateral morning glory anomaly of the optic nerve. Ductions of the right eye were normal, but the left eye had severely impaired ductions in all directions, left hypotropia, and esotropia. Under anesthesia, the left eye could not be rotated freely in any direction. Bilateral Tessier cleft number 10 was implicated by the presence of colobomata of the middle third of the upper eyelids and eyebrows. As the cleft continued into the hairline, there was marked anterior scalp alopecia. Computed x-ray tomography showed a left middle cranial fossa arachnoid cyst and calcification of the reflected tendon of the superior oblique muscle, trochlea, and underlying sclera, with downward and lateral globe displacement. Discussion Tessier 10 clefts are very rare and usually associated with encephalocele. Bilateral 10 clefts have not been reported previously. In this case, there was coexisting unilateral morning glory anomaly and arachnoid cyst of the left middle cranial fossa but no encephalocele. Conclusions Bilateral Tessier facial cleft 10 may be associated with alopecia, morning glory anomaly, epibulbar dermoids, arachnoid cyst, and restrictive strabismus. PMID:20856062
[Posterior decompression of the craniovertebral junction in syringomyelia combined with Chiari-1 malformation in children].
Sanakoeva, A V; Korshunov, A E; Kadyrov, Sh U; Khukhlaeva, E A; Kushel', Yu V
to develop the algorithm for defining the amount of posterior decompression of the craniovertebral junction in children with syringomyelia combined with Chiari-1 malformation. Sixty eight children with syringomyelia and Chiari-1 malformation, under age of 18 years, underwent posterior decompression of the craniovertebral junction (PDCVJ) in the period from January 2001 to June 2016. Seven (10%) patients underwent extradural decompression (EDD), 16 (24%) patients underwent extra-arachnoid duraplasty (EAD), 25 (37%) patients underwent intra-arachnoid dissection (IAD) and duraplasty, and 20 (29%) patients underwent PDCVJ and placement of a fourth ventricle-subarachnoid shunt. Clinical improvement occurred in 85% of patients, and stabilization was observed in 11% of patients. Syringomyelia regressed in 78% of cases. There were no complications associated with EDD; however, re-operation was required in 3 (43%) cases. In the case of EAD, treatment results were satisfactory in 11 (79%) patients; re-operation was required in 2 (12.5%) cases; there were no complications in the early postoperative period. The highest complication rate of 6 (30%) cases was associated with shunt placement and duraplasty. However, long-term results in this group of patients were satisfactory in 16 (94%) cases, and MRI-based positive changes were observed in 100% of cases. According to our analysis, EAD is the method of choice for PDCVJ in children with syringomyelia and Chiari-1 malformation without myelopathy symptoms. In the presence of myelopathy symptoms, intra-arachnoid dissection (with or without shunting) is an acceptable alternative. To our opinion, the use of EDD in syringomyelia is unadvisable.
Conway Morris: Extraterrestrials: Aliens like us?
NASA Astrophysics Data System (ADS)
Morris, Simon Conway
So what are they going to be like, those long-expected extraterrestrials? Hideous hydrocarbon arachnoids, waving laser cannons as they chase screaming humans, repulsively surveying the scene through empathy-free compound eyes? Or maybe laughing bipeds, chatting away, holding a glass of wine, a bit like us?
Primary extracranial meningioma of the mandible.
Mosqueda-Taylor, Adalberto; Domínguez-Malagon, Hugo; Cano-Valdez, Ana-Maria; Montiel-Hernandez, Ana-Maria
Meningiomas are benign tumors of mesodermal origin that arise from arachnoid cell clusters that penetrate the dura to form arachnoid villi. These neoplasms represent one of the most common neoplasms developing within the central nervous system and are usually located at points of entry of vessels and nerves through the dura. Extracranial meningiomas (EM) comprise only 2% of all meningiomas, and only six cases of primary EM of the jawbones have been described to date. They may arise as an extension of intracranial meningiomas or as primary tumors and may be clinically indistinguishable from other benign tumours of the jaws, as they usually present as a well-delineated unencapsulated tumors. In this article a case of primary intramandibular primary EM that appeared as a well-defined osteolytic radiolucent lesion of the jaw is reported. The salient clinico-pathological features of this case is compared to those previously reported in the literature and differential diagnosis and therapeutic considerations are discussed.
Outer brain barriers in rat and human development.
Brøchner, Christian B; Holst, Camilla B; Møllgård, Kjeld
Complex barriers at the brain's surface, particularly in development, are poorly defined. In the adult, arachnoid blood-cerebrospinal fluid (CSF) barrier separates the fenestrated dural vessels from the CSF by means of a cell layer joined by tight junctions. Outer CSF-brain barrier provides diffusion restriction between brain and subarachnoid CSF through an initial radial glial end feet layer covered with a pial surface layer. To further characterize these interfaces we examined embryonic rat brains from E10 to P0 and forebrains from human embryos and fetuses (6-21st weeks post-conception) and adults using immunohistochemistry and confocal microscopy. Antibodies against claudin-11, BLBP, collagen 1, SSEA-4, MAP2, YKL-40, and its receptor IL-13Rα2 and EAAT1 were used to describe morphological characteristics and functional aspects of the outer brain barriers. Claudin-11 was a reliable marker of the arachnoid blood-CSF barrier. Collagen 1 delineated the subarachnoid space and stained pial surface layer. BLBP defined radial glial end feet layer and SSEA-4 and YKL-40 were present in both leptomeningeal cells and end feet layer, which transformed into glial limitans. IL-13Rα2 and EAAT1 were present in the end feet layer illustrating transporter/receptor presence in the outer CSF-brain barrier. MAP2 immunostaining in adult brain outlined the lower border of glia limitans; remnants of end feet were YKL-40 positive in some areas. We propose that outer brain barriers are composed of at least 3 interfaces: blood-CSF barrier across arachnoid barrier cell layer, blood-CSF barrier across pial microvessels, and outer CSF-brain barrier comprising glial end feet layer/pial surface layer.
Outer brain barriers in rat and human development
Brøchner, Christian B.; Holst, Camilla B.; Møllgård, Kjeld
Complex barriers at the brain's surface, particularly in development, are poorly defined. In the adult, arachnoid blood-cerebrospinal fluid (CSF) barrier separates the fenestrated dural vessels from the CSF by means of a cell layer joined by tight junctions. Outer CSF-brain barrier provides diffusion restriction between brain and subarachnoid CSF through an initial radial glial end feet layer covered with a pial surface layer. To further characterize these interfaces we examined embryonic rat brains from E10 to P0 and forebrains from human embryos and fetuses (6–21st weeks post-conception) and adults using immunohistochemistry and confocal microscopy. Antibodies against claudin-11, BLBP, collagen 1, SSEA-4, MAP2, YKL-40, and its receptor IL-13Rα2 and EAAT1 were used to describe morphological characteristics and functional aspects of the outer brain barriers. Claudin-11 was a reliable marker of the arachnoid blood-CSF barrier. Collagen 1 delineated the subarachnoid space and stained pial surface layer. BLBP defined radial glial end feet layer and SSEA-4 and YKL-40 were present in both leptomeningeal cells and end feet layer, which transformed into glial limitans. IL-13Rα2 and EAAT1 were present in the end feet layer illustrating transporter/receptor presence in the outer CSF-brain barrier. MAP2 immunostaining in adult brain outlined the lower border of glia limitans; remnants of end feet were YKL-40 positive in some areas. We propose that outer brain barriers are composed of at least 3 interfaces: blood-CSF barrier across arachnoid barrier cell layer, blood-CSF barrier across pial microvessels, and outer CSF-brain barrier comprising glial end feet layer/pial surface layer. PMID:25852456
Communicating hydrocephalus caused by Aspergillus flavus.
Bryan, C S; DiSalvo, A F; Huffman, L J; Kaplan, W; Kaufman, L
A patient with a past history of sporadic parenteral drug abuse had communicating hydrocephalus associated with arachnoiditis over the lumbar spinal cord. The diagnosis of aspergillosis was made by a newly described immunofluorescent staining procedure and was later confirmed by culture. The spectrum of central nervous system aspergillosis associated with drug abuse is reviewed.
Evaluation of operative procedures for symptomatic outcome after decompression surgery for Chiari type I malformation.
Kalb, Samuel; Perez-Orribo, Luis; Mahan, Mark; Theodore, Nicholas; Nakaji, Peter; Bristol, Ruth E
The wide spectrum of symptoms and radiographic findings in patients with Chiari I malformation makes the decision to proceed with intervention controversial. We evaluated symptomatic outcomes using diverse surgical techniques in 104 patients who underwent decompression surgery. The symptoms of most patients improved. Patients with syringomyelia showed less symptomatic improvement; however, syringomyelia was not associated with postoperative symptomatic worsening. Durotomy was performed in 97.1% and arachnoid opening was performed in 60.6% with visualization of the fourth ventricle in 51.9% of patients. Neither arachnoid opening nor fourth ventricle visualization was associated with the clinical outcome. Duraplasty was performed in 94.2% of patients. A Chiari plate was used in 13.4% of patients and was associated with favorable outcomes. Use of postoperative steroids or muscle relaxants was not associated with outcome. Syringomyelia showed a 62.5% improvement rate on postoperative MRI. In conclusion, bony decompression and dural opening are important aspects of Chiari I surgery, with symptomatic improvement observed in most patients. Copyright © 2012. Published by Elsevier Ltd.
Anatomic variants in Dandy-Walker complex.
Jurcă, Maria Claudia; Kozma, Kinga; Petcheşi, CodruŢa Diana; Bembea, Marius; Pop, Ovidiu Laurean; MuŢiu, Gabriela; Coroi, Mihaela Cristiana; Jurcă, Alexandru Daniel; Dobjanschi, Luciana
Dandy-Walker complex (DWC) is a malformative association of the central nervous system. DWC includes four different types: Dandy-Walker malformation (vermis agenesis or hypoplasia, cystic dilatation of the fourth ventricle and a large posterior fossa); Dandy-Walker variant (vermis hypoplasia, cystic dilatation of the fourth ventricle, normal posterior fossa); mega cysterna magna (large posterior fossa, normal vermis and fourth ventricle) and posterior fossa arachnoid cyst. We present and discuss four cases with different morphological and clinical forms of the Dandy-Walker complex. In all four cases, diagnosis was reached by incorporation of clinical (macrocephaly, seizures) and imaging [X-ray, computed tomography (CT), magnetic resonance imaging (MRI)] data. Two patients were diagnosed with Dandy-Walker complex, one patient was diagnosed with Dandy-Walker variant in a rare association with neurofibromatosis and one patient was diagnosed with a posterior fossa arachnoid cyst associated with left-sided Claude Bernard-Horner syndrome, congenital heart disease (coarctation of the aorta, mitral stenosis) and gastroesophageal reflux. In all forms of DWC, the clinical, radiological and functional manifestations are variable and require adequate diagnostic and therapeutic measures.
Use of an Android application "clinometer" for measurement of head down tilt given during subarachnoid block.
Dixit, R B; Neema, M M
Head down tilt is given to patients after sub arachnoid block for adjustment of height of block. However, the amount of tilt given is subjective and cannot be documented. We used an android application named "clinometer" to measure exact degree of tilt given by anesthesiologists as their routine practice. This observational study, at a medical college hospital, was done in 130 patients given sub arachnoid block for lower abdominal surgeries. We observed and documented vital data of patients and measured tilt given by application "clinometer." We observed that the application was easy to use and measured tilt each time. The result obtained can be documented, digitally saved and transferred. In 130 patients studied, we observed incidence of degree of tilt as follows: 6-8° tilt in 38 patients (29.23%), 8-10 in 36 patients (27.69%), 10-12 in 30 patients (23.08%), 12-14 in 12 patients (9.23%) and 14-16° tilt in 14 patients (10.77%). Use of application was received with enthusiasm by practicing anesthesiologists. Various possible uses of this application are discussed.
[The meninges, an anatomical point of view].
Sakka, L; Chazal, J
The meninges correspond to an anatomical concept. For the morphologist, the microscopic organization, the hypothetical presence of a subdural space, the nature of the interface between the deep meningeal layer and the nervous parenchyma in the perivascular spaces are the central issues. For the clinician, dynamic aspects of cerebrospinal fluid flow, secretion, and resorption are essential factors with practical consequences in terms of disease and patient management. Comparative anatomy, embryology, and organogenesis provide an interesting perspective for the descriptive and functional anatomy of the meninges. Usually considered as protective membranes, the meninges play a prominent role in the development and maintenance of the central nervous system. The meninges are in constant evolution, from their formation to senescence. The meninges present three layers in children and adults: the dura mater, the arachnoid and the pia mater. The cerebrospinal fluid is secreted by the choroid plexuses, flows through the ventricles and the subarachnoid space, and is absorbed by arachnoid granulations. Other sites of secretion and resorption are suggested by comparative anatomy and human embryology and organogenesis.
Mitomycin C, 5-fluorouracil, and cyclosporin A prevent epidural fibrosis in an experimental laminectomy model.
Yildiz, Kartal Hakan; Gezen, Ferruh; Is, Merih; Cukur, Selma; Dosoglu, Murat
This study examined the preventive effects of the local application of mitomycin C (MMC), 5-fluorouracil (5-FU), and cyclosporine A (CsA) in minimizing spinal epidural fibrosis in a rat laminectomy model. Thirty-two 2-year-old male Wistar albino rats, each weighing 400 +/- 50 g, were divided into four equal groups: sham, MMC, 5-FU, and CsA. Each rat underwent laminectomy at the L5-L6 lumbar level. Cotton pads (4 x 4 mm2) soaked with MMC (0.5 mg/ml), 5-FU (5 ml/mg), or CsA (5 mg/ml) were placed on the exposed dura for 5 min. Thirty days after surgery, the rats were killed and the epidural fibrosis, fibroblast density, inflammatory cell density, and arachnoid fibrosis were quantified. The epidural and arachnoid fibroses were reduced significantly in the treatment groups compared to the sham group. Fibroblast cell density and inflammatory cell density were decreased significantly in the MMC and 5-FU groups, but were similar in the sham and CsA groups. The decreased rate of epidural fibrosis was promising. Further studies in humans are needed to determine the short- and long-term complications of the agents used here.
Dumbbell meningioma of the cervico-clavicular region.
Hlavka, V; Miklić, P; Besenski, N; Miklić, D; Franz, G
The authors are reporting on a case of a 55-year-old man with an epidural meningioma in the region from the C VII. to the Th I. segment. The tumor encircled this region, and to the front and right involved the channels through which pass the C VI, C VII. and C VIII. roots. Subdurally, no tumoral mass was found. Another part of this tumor, of the same histological architecture as the epidural cervicospinal part was found in the supraclavicular region to the right, closely connected to the arteries and nerves of this region. The authors discuss the possibility of the tumoral occurrence at this site, primarily taking into account the origin of this tumor from the cells of the outer surface of the arachnoidea, i.e. cap cells which can invade the dura, with later separation from the main arachnoidal layer. The other possibility of such dumbbell meningioma occurring at the outgoing openings of the neural paths from the spinal channel should be looked for in the remnants of the arachnoidal cells in the region of the outgoing openings. In the paper are also discussed and correlated clinico-pathological, CT and angiographic findings.
Use of an Android application “clinometer” for measurement of head down tilt given during subarachnoid block
Dixit, RB; Neema, MM
Context: Head down tilt is given to patients after sub arachnoid block for adjustment of height of block. However, the amount of tilt given is subjective and cannot be documented. Aims: We used an android application named “clinometer” to measure exact degree of tilt given by anesthesiologists as their routine practice. Settings and Design: This observational study, at a medical college hospital, was done in 130 patients given sub arachnoid block for lower abdominal surgeries. Materials and Methods: We observed and documented vital data of patients and measured tilt given by application “clinometer.” Results: We observed that the application was easy to use and measured tilt each time. The result obtained can be documented, digitally saved and transferred. In 130 patients studied, we observed incidence of degree of tilt as follows: 6-8° tilt in 38 patients (29.23%), 8-10 in 36 patients (27.69%), 10-12 in 30 patients (23.08%), 12-14 in 12 patients (9.23%) and 14-16° tilt in 14 patients (10.77%). Use of application was received with enthusiasm by practicing anesthesiologists. Various possible uses of this application are discussed. PMID:26955307
seizures , sub-arachnoid hemorrhaging, prenatal strokes , alopecia universalis (hair loss disease) husband is Active Duty, came from Ft. Hood 4...restriction, failure to thrive, a seizure disorder, cortical blindness husband is Active Duty Army 20 diagnosed with severe cerebral palsy at 3 mo old ex...linked hyper IgM); oldest son has cancer too Active Duty Army officer (wife and husband participated) 3 severe cerebral palsy, seizure disorder
Mitomycin C, 5-fluorouracil, and cyclosporin A prevent epidural fibrosis in an experimental laminectomy model
Yildiz, Kartal Hakan; Gezen, Ferruh; Cukur, Selma; Dosoglu, Murat
This study examined the preventive effects of the local application of mitomycin C (MMC), 5-fluorouracil (5-FU), and cyclosporine A (CsA) in minimizing spinal epidural fibrosis in a rat laminectomy model. Thirty-two 2-year-old male Wistar albino rats, each weighing 400 ± 50 g, were divided into four equal groups: sham, MMC, 5-FU, and CsA. Each rat underwent laminectomy at the L5–L6 lumbar level. Cotton pads (4 × 4 mm2) soaked with MMC (0.5 mg/ml), 5-FU (5 ml/mg), or CsA (5 mg/ml) were placed on the exposed dura for 5 min. Thirty days after surgery, the rats were killed and the epidural fibrosis, fibroblast density, inflammatory cell density, and arachnoid fibrosis were quantified. The epidural and arachnoid fibroses were reduced significantly in the treatment groups compared to the sham group. Fibroblast cell density and inflammatory cell density were decreased significantly in the MMC and 5-FU groups, but were similar in the sham and CsA groups. The decreased rate of epidural fibrosis was promising. Further studies in humans are needed to determine the short- and long-term complications of the agents used here. PMID:17387523
Subarachnoid, subdural and interdural spaces at the clival region: an anatomical study.
Ayberk, Giyas; Ozveren, Mehmet Faik; Aslan, Sevil; Yaman, Mesut Emre; Yaman, Onur; Kayaci, Selim; Tekdemir, Ibrahim
We aimed to show the significance of the anterior pontine membrane as a determining structure between the subdural and subarachnoid space in the clival region. Five adult cadaver heads and five cerebral hemispheres were used. The skull vault and hemipheres were removed by sectioning through the pontomesencephalic junction. Five other heads hemispheres were removed but the arachnoid membrane was protected and the cerebral side of the clival dura mater was dissected. In another specimen, the dural porus of the abducens nerve was sectioned for histological evaluation. Three cases of hematoma at the clivus were presented to support our findings. The anterior pontine membrane is the arachnoid membrane forming the anterior wall of the prepontine cistern with its lateral extension at the skull base. This membrane forms the subdural and subarachnoid spaces by forming a barrier between the clival dura mater and neurovascular structures of the brainstem. There were rigid fibrous trabeculations between both cerebral and periosteal dural layers forming the basilar plexus as the interdural space in the clivus. The anterior pontine membrane separates the subdural and subarachnoid spaces at the clival region. The hematomas of the clival region require to be evaluated with consideration given to the existance of the subdural space.
Change in head posture and character of nystagmus in a patient with neurological upbeat nystagmus.
Gonzalez, Caleb; Seth, Rajeev K; Ramos-Esteban, Jerome C
To report a case of a patient with chin-up head posture and presumed congenital toxoplasmosis chorioretinal scars, who had a change in the character of the nystagmus and therefore the head posture following treatment for a neurological upbeat nystagmus. A 5 month old female presented with a chin up head posture and upbeat nystagmus. Magnetic resonance imaging of the brain revealed an arachnoid cyst in the area of the pineal gland. Nine months after cyst-peritoneal shunt surgery, the upbeat nystagmus was dampened but change in character to a rotary nystagmus worse on the left gaze. The patient had assumed a left face turn, shifting the null point from the vertical to the horizontal plane. The left face turn was successfully corrected at age eight years with a Kestenbaum procedure. This case emphasizes the possibility of having two distinct types of nystagmus associated with two etiologies. In this case, an acquired upbeat nystagmus secondary to an arachnoid cyst, and a congenital left rotary nystagmus from the chorioretinal scars. Furthermore, there can be a change in head position and character of nystagmus after treating the cause of the central motility disorder, thereby affecting the choice and timing of surgical intervention to correct the head positioning.
Macrophages and dendritic cells in the rat meninges and choroid plexus: three-dimensional localisation by environmental scanning electron microscopy and confocal microscopy.
McMenamin, Paul G; Wealthall, Rosamund J; Deverall, Marie; Cooper, Stephanie J; Griffin, Brendan
The present investigation provides novel information on the topographical distribution of macrophages and dendritic cells (DCs) in normal meninges and choroid plexus of the rat central nervous system (CNS). Whole-mounts of meninges and choroid plexus of Lewis rats were incubated with various anti-leucocyte monoclonal antibodies and either visualised with gold-conjugated secondary antibody followed by silver enhancement and subsequent examination by environmental scanning electron microscopy or by the use of fluorochromes and confocal microscopy. Large numbers of MHC class II(+) putative DCs were identified on the internal or subarachnoid aspect of dural whole-mounts, on the surface of the cortex (pia/arachnoid) and on the surface of the choroid plexus. Occupation of these sites would allow DCs access to cerebrospinal fluid (CSF) and therefore allow antigens into the subarachnoid space and ventricles. By contrast, macrophages were less evident at sites exposed to CSF and were more frequently located within the connective tissue of the dura/arachnoid and choroid plexus stroma and also in a sub-pial location. The present data suggest that DC may be strategically located within the CNS to sample CSF-borne antigens. Furthermore, the data suggest that CNS tissue samples collected without careful removal of the meninges may inadvertently be contaminated by DCs and meningeal macrophages.
Histopathological Alterations after Single Epidural Injection of Ropivacaine, Methylprednizolone Acetate, or Contrast Material in Swine
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kitsou, Maria-Chrysanthi; Kostopanagiotou, Georgia; Kalimeris, Konstantinos
Purpose: The consequences from the injection of different types of drugs in the epidural space remains unknown. Increasing evidence suggests that localized inflammation, fibrosis, and arachnoiditis can complicate sequential epidural blockades, or even epidural contrast injection. We investigate the in vivo effect of epidural injections in the epidural space in an animal model. Materials and Methods: A group of ten male adult pigs, five punctures to each at distinct vertebral interspaces under general anesthesia, were examined, testing different drugs, used regularly in the epidural space (iopamidol, methylprednisolone acetate, ropivacaine). Each site was marked with a percutaneous hook wire marker. Histologicalmore » analysis of the epidural space, the meninges, and the underlying spinal cord of the punctured sites along with staining for caspase-3 followed 20 days later. Results: The epidural space did not manifest adhesions or any other pathology, and the outer surface of the dura was not impaired in any specimen. The group that had the contrast media injection showed a higher inflammation response compared to the other groups (P = 0.001). Positive staining for caspase-3 was limited to <5% of neurons with all substances used. Conclusion: No proof of arachnoiditis and/or fibrosis was noted in the epidural space with the use of the above-described drugs. A higher inflammation rate was noted with the use of contrast media.« less
Intramedullary Recurrence of a Thoracic Meningioma-Presentation of an Unusual Case and Review of the Literature.
Piazza, Matthew A; Ramayya, Ashwin G; Geiger, Geoffrey A; Alonso-Basanta, Michelle; Nasrallah, MacLean P; Welch, William C; Ozturk, Ali K
Spinal meningiomas are typically extra-axial, slow-growing, benign tumors that arise from the arachnoid cap cells. Intramedullary spinal meningiomas are exceedingly rare with few cases reported in the literature. A 64-year-old man with a history of grade I thoracic meningioma at the T4 level resected initially in 1989 and who required reoperation in 2013 for intradural, extramedullary recurrence of tumor presented again in 2015 with gait difficulty. Magnetic resonance imaging revealed a soft tissue mass at the T3 to T4 levels on the left side of the canal that was mildly enhancing on T1 contrasted sequences. The patient was taken to the operating room, where a purely intramedullary recurrence was discovered without extramedullary extension or a dural-based attachment. The intramedullary tumor was completely resected, and postoperatively the patient recovered well and was at his neurologic baseline. The patient ultimately underwent proton beam radiotherapy because this tumor, although benign, had recurred twice. Intramedullary spinal meningiomas, particularly intramedullary low-grade recurrence of a previously extramedullary tumor, are rare phenomena. Although the pathogenic mechanisms are not well understood, intramedullary recurrence as described in this patient may reflect extrinsic factors related to prior surgical resections in addition to histologic progression. When operating on recurrent extramedullary lesions, aggressive arachnoid dissection may predispose patients to unusual patterns of recurrence. Copyright © 2016 Elsevier Inc. All rights reserved.
Genetic and Functional Heterogeneity of Tumors in Neurofibromatosis 2
mapped to the human genome build 37 (hg19) through BWA v. 0.5.9  with parameters -q 5 -l 32 -k 2 –o 1. The resulting alignments were further sorted...see Table 2). Table 2 – Isogenic human arachnoidal cell (AC) clones with NF2 (exon 8) inactivating mutations generated by CRISPR/Cas genome editing...libraries were aligned to the human genome (GrCH37, Ensembl build 71) using Gsnap  version 2014_12_19. Expression levels of genes in the units of count
Developmental and perinatal brain diseases.
Adle-Biassette, Homa; Golden, Jeffery A; Harding, Brian
This chapter briefly describes the normal development of the nervous system, the neuropathology and pathophysiology of acquired and secondary disorders affecting the embryo, fetus, and child. They include CNS manifestations of chromosomal change; forebrain patterning defects; disorders of the brain size; cell migration and specification disorders; cerebellum, hindbrain and spinal patterning defects; hydrocephalus; secondary malformations and destructive pathologies; vascular malformations; arachnoid cysts and infectious diseases. The distinction between malformations and disruptions is important for pathogenesis and genetic counseling. Copyright © 2017 Elsevier B.V. All rights reserved.
Syndrome of normal pressure hydrocephalus: possible relation to hypertensive and arteriosclerotic vasculopathy.
Koto, A; Rosenberg, G; Zingesser, L H; Horoupian, D; Katzman, R
A patient with clinical features of idiopathic normal pressure hydrocephalus, who responded dramatically to shunting, was found a necropsy to have a severe hypertensive and arteriosclerotic vasculopathy with multiple lacunar infarcts. There was no pathological evidence of thickened leptomeninges, fibrosis of the arachnoid villi, or Alzheimer's disease. An abnormal absorption mechanism was demonstrated with cisternography and by an increase in the concentration of homovanillic acid in the cerebrospinal fluid. It is suggested that vascular changes may play an important role in the pathophysiology in some cases of normal pressure hydrocephalus. Images PMID:845610
Adult manifestation of the Dandy-Walker syndrome. Report of two cases with review of the literature.
Unsgaard, G; Sand, T; Støvring, J; Ringkjøb, R
Two cases of Dandy-Walker syndrome that became manifest in adult life are reported. A review of the literature of Dandy-Walker syndrome revealed 13 additional cases with onset in adult life and three cases that could not be differentiated from arachnoid cysts. While shunting is the primary treatment in infantile Dandy-Walker, the usual treatment of adult Dandy-Walker has been excision of the membrane covering the enlarged fourth ventricle. The outcome of our two cases treated with membrane excision indicates that primary shunting should also be tried in adult Dandy-Walker.
Orphan disease: Cherubism, optic atrophy, and short stature.
Jeevanandham, Balaji; Ramachandran, Rajoo; Dhanapal, Vignesh; Subramanian, Ilanchezhian; Sai, Venkata
A 12-year-old female presented with complaints of progressive visual impairment in both her eyes. On clinical examination, she was short for her age and her ophthalmoscopic examination revealed bilateral optic atrophy. Computed tomography of the patient revealed multiple expansile lytic lesions of mandible suggesting cherubism. The optic atrophy was confirmed on magnetic resonance imaging, which additionally revealed bilateral retrocerebellar arachnoid cysts. This association of cherubism with optic atrophy and short stature was grouped as orphan disease by National Institutes of Health and only one case was reported in the literature so far.
Global scale concentrations of volcanic activity on Venus: A summary of three 23rd Lunar and Planetary Science Conference abstracts. 1: Venus volcanism: Global distribution and classification from Magellan data. 2: A major global-scale concentration of volcanic activity in the Beta-Atla-Themis region of Venus. 3: Two global concentrations of volcanism on Venus: Geologic associations and implications for global pattern of upwelling and downwelling
NASA Technical Reports Server (NTRS)
Crumpler, L. S.; Aubele, Jayne C.; Head, James W.; Guest, J.; Saunders, R. S.
As part of the analysis of data from the Magellan Mission, we have compiled a global survey of the location, dimensions, and subsidiary notes of all identified volcanic features on Venus. More than 90 percent of the surface area was examined and the final catalog comprehensively identifies 1548 individual volcanic features larger than approximately 20 km in diameter. Volcanic features included are large volcanoes, intermediate volcanoes, fields of small shield volcanoes, calderas, large lava channels, and lava floods as well as unusual features first noted on Venus such as coronae, arachnoids, and novae.
Role of Merlin in the Growth and Transformation of Arachnoidal Cells
studies on the chemotherapeutic agent, hydroxyurea , were performed using meningioma cells grown in the galea (25), and tests on celecoxib were performed...Anders M, Kiesewetter F, Marschalek R, Koch UH, Fahlbusch R (1997) Hydroxyurea for treatment of unresectable and recurrent meningiomas. I. Inhibition of
Multiplicity of cerebrospinal fluid functions: New challenges in health and disease
Johanson, Conrad E; Duncan, John A; Klinge, Petra M; Brinker, Thomas; Stopa, Edward G; Silverberg, Gerald D
benefits. Finally, CSF reabsorption via multiple pathways (olfactory and spinal arachnoidal bulk flow) is likely complemented by fluid clearance across capillary walls (aquaporin 4) and arachnoid villi when CSFP and fluid retention are markedly elevated. A model is presented that links CSF and ISF homeostasis to coordinated fluxes of water and solutes at both the blood-CSF and blood-brain transport interfaces. Outline 1 Overview 2 CSF formation 2.1 Transcription factors 2.2 Ion transporters 2.3 Enzymes that modulate transport 2.4 Aquaporins or water channels 2.5 Receptors for neuropeptides 3 CSF pressure 3.1 Servomechanism regulatory hypothesis 3.2 Ontogeny of CSF pressure generation 3.3 Congenital hydrocephalus and periventricular regions 3.4 Brain response to elevated CSF pressure 3.5 Advances in measuring CSF waveforms 4 CSF flow 4.1 CSF flow and brain metabolism 4.2 Flow effects on fetal germinal matrix 4.3 Decreasing CSF flow in aging CNS 4.4 Refinement of non-invasive flow measurements 5 CSF volume 5.1 Hemodynamic factors 5.2 Hydrodynamic factors 5.3 Neuroendocrine factors 6 CSF turnover rate 6.1 Adverse effect of ventriculomegaly 6.2 Attenuated CSF sink action 7 CSF composition 7.1 Kidney-like action of CP-CSF system 7.2 Altered CSF biochemistry in aging and disease 7.3 Importance of clearance transport 7.4 Therapeutic manipulation of composition 8 CSF recycling in relation to ISF dynamics 8.1 CSF exchange with brain interstitium 8.2 Components of ISF movement in brain 8.3 Compromised ISF/CSF dynamics and amyloid retention 9 CSF reabsorption 9.1 Arachnoidal outflow resistance 9.2 Arachnoid villi vs. olfactory drainage routes 9.3 Fluid reabsorption along spinal nerves 9.4 Reabsorption across capillary aquaporin channels 10 Developing translationally effective models for restoring CSF balance 11 Conclusion PMID:18479516
CSF Flow in the Brain in the Context of Normal Pressure Hydrocephalus.
Bradley, W G
CSF normally flows back and forth through the aqueduct during the cardiac cycle. During systole, the brain and intracranial vasculature expand and compress the lateral and third ventricles, forcing CSF craniocaudad. During diastole, they contract and flow through the aqueduct reverses. Hyperdynamic CSF flow through the aqueduct is seen when there is ventricular enlargement without cerebral atrophy. Therefore, patients presenting with clinical normal pressure hydrocephalus who have hyperdynamic CSF flow have been found to respond better to ventriculoperitoneal shunting than those with normal or decreased CSF flow. Patients with normal pressure hydrocephalus have also been found to have larger intracranial volumes than sex-matched controls, suggesting that they may have had benign external hydrocephalus as infants. While their arachnoidal granulations clearly have decreased CSF resorptive capacity, it now appears that this is fixed and that the arachnoidal granulations are not merely immature. Such patients appear to develop a parallel pathway for CSF to exit the ventricles through the extracellular space of the brain and the venous side of the glymphatic system. This pathway remains functional until late adulthood when the patient develops deep white matter ischemia, which is characterized histologically by myelin pallor (ie, loss of lipid). The attraction between the bare myelin protein and the CSF increases resistance to the extracellular outflow of CSF, causing it to back up, resulting in hydrocephalus. Thus idiopathic normal pressure hydrocephalus appears to be a "2 hit" disease: benign external hydrocephalus in infancy followed by deep white matter ischemia in late adulthood. © 2015 by American Journal of Neuroradiology.
False localizing sign of cervico-thoracic CSF leak in spontaneous intracranial hypotension.
Schievink, Wouter I; Maya, M Marcel; Chu, Ray M; Moser, Franklin G
Spontaneous spinal CSF leaks are an important cause of new-onset headaches. Such leaks are reported to be particularly common at the cervico-thoracic junction. The authors undertook a study to determine the significance of these cervico-thoracic CSF leaks. The patient population consisted of a consecutive group of 13 patients who underwent surgery for CSF leak repair based on CT myelography showing CSF extravasation at the cervico-thoracic junction but without any evidence of an underlying structural lesion. The mean age of the 9 women and 4 men was 41.2 years. Extensive extrathecal longitudinal CSF collections were demonstrated in 11 patients. At surgery, small leaking arachnoid cysts were found in 2 patients. In the remaining 11 patients, no clear source of CSF leakage could be identified at surgery. Resolution of symptoms was achieved in both patients with leaking arachnoid cysts, but in only 3 of the 11 patients with negative intraoperative findings. Postoperative spinal imaging was performed in 9 of the 11 patients with negative intraoperative findings and showed persistence of the longitudinal intraspinal extradural CSF. Further imaging revealed the site of the CSF leak to be ventral to the thoracic spinal cord. Five of these patients underwent microsurgical repair of the ventral CSF leak with resolution of symptoms in all 5 patients. Cervico-thoracic extravasation of dye on myelography does not necessarily indicate the site of the CSF leak. Treatment directed at this site should not be expected to have a high probability of sustained improvement of symptoms. © 2015 American Academy of Neurology.
Utilizing multiple scale models to improve predictions of extra-axial hemorrhage in the immature piglet.
Scott, Gregory G; Margulies, Susan S; Coats, Brittany
Traumatic brain injury (TBI) is a leading cause of death and disability in the USA. To help understand and better predict TBI, researchers have developed complex finite element (FE) models of the head which incorporate many biological structures such as scalp, skull, meninges, brain (with gray/white matter differentiation), and vasculature. However, most models drastically simplify the membranes and substructures between the pia and arachnoid membranes. We hypothesize that substructures in the pia-arachnoid complex (PAC) contribute substantially to brain deformation following head rotation, and that when included in FE models accuracy of extra-axial hemorrhage prediction improves. To test these hypotheses, microscale FE models of the PAC were developed to span the variability of PAC substructure anatomy and regional density. The constitutive response of these models were then integrated into an existing macroscale FE model of the immature piglet brain to identify changes in cortical stress distribution and predictions of extra-axial hemorrhage (EAH). Incorporating regional variability of PAC substructures substantially altered the distribution of principal stress on the cortical surface of the brain compared to a uniform representation of the PAC. Simulations of 24 non-impact rapid head rotations in an immature piglet animal model resulted in improved accuracy of EAH prediction (to 94 % sensitivity, 100 % specificity), as well as a high accuracy in regional hemorrhage prediction (to 82-100 % sensitivity, 100 % specificity). We conclude that including a biofidelic PAC substructure variability in FE models of the head is essential for improved predictions of hemorrhage at the brain/skull interface.
Multiple burr hole surgery as a treatment modality for pediatric moyamoya disease
Kapu, Ravindranath; Symss, Nigel Peter; Cugati, Goutham; Pande, Anil; Vasudevan, Chakravarthy M.; Ramamurthi, Ravi
Objective: To re-emphasize that indirect revascularization surgery alone, where multiple burr holes and arachnoid openings are made over both cerebral hemispheres, is beneficial in the treatment of moyamoya disease (MMD) in children. Clinical Presentation: We report a 10-year-old boy who presented with complaints of episodic headache for the last 5 years. At the peak of his headache he had visual disturbances and acute onset weakness of left-sided limbs, recovering within a few minutes. He had no focal neurological deficits. Radiological investigations revealed abnormal findings, demonstrating the features of MMD. Surgical Management: He underwent bilateral multiple burr holes, dural and arachnoid opening over the frontal, parietal and temporal regions of each hemisphere. The elevated periosteal flap was placed in contact with the exposed brain through each burr hole. Results: On 6-months follow-up he had only one episode of transient ischemic attack. Postoperative four vessel angiogram demonstrated excellent cerebral revascularization around the burr hole sites, and single photon emission computerized tomography imaging showed hypoperfusion in the right temporo-occipital area suggestive of an old infarct with no other perfusion defect in the rest of the brain parenchyma. Conclusion: In children with MMD this relatively simple surgical technique is effective and safe, and can be used as the only treatment without supplementary revascularization procedures. This procedure can be done in a single stage on both sides and the number of burr holes made over each hemisphere depends on the extent of the disease. PMID:21559155
A Current Perspective on the Historical Geographic Distribution of the Endangered Muriquis (Brachyteles spp.): Implications for Conservation
The muriqui (Brachyteles spp.), endemic to the Atlantic Forest of Brazil, is the largest primate in South America and is endangered, mainly due to habitat loss. Its distribution limits are still uncertain and need to be resolved in order to determine their true conservation status. Species distribution modeling (SDM) has been used to estimate potential species distributions, even when information is incomplete. Here, we developed an environmental suitability model for the two endangered species of muriqui (Brachyteles hypoxanthus and B. arachnoides) using Maxent software. Due to historical absence of muriquis, areas with predicted high habitat suitability yet historically never occupied, were excluded from the predicted historical distribution. Combining that information with the model, it is evident that rivers are potential dispersal barriers for the muriquis. Moreover, although the two species are environmentally separated in a large part of its distribution, there is a potential contact zone where the species apparently do not overlap. This separation might be due to either a physical (i.e., Serra da Mantiqueira mountains) or a biotic barrier (the species exclude one another). Therefore, in addition to environmental characteristics, physical and biotic barriers potentially shaped the limits of the muriqui historical range. Based on these considerations, we proposed the adjustment of their historical distributional limits. Currently only 7.6% of the predicted historical distribution of B. hypoxanthus and 12.9% of B. arachnoides remains forested and able to sustain viable muriqui populations. In addition to measurement of habitat loss we also identified areas for conservation concern where new muriqui populations might be found. PMID:26943910
Patterns of contrast enhancement in the brain and meninges.
Smirniotopoulos, James G; Murphy, Frances M; Rushing, Elizabeth J; Rees, John H; Schroeder, Jason W
Contrast material enhancement for cross-sectional imaging has been used since the mid 1970s for computed tomography and the mid 1980s for magnetic resonance imaging. Knowledge of the patterns and mechanisms of contrast enhancement facilitate radiologic differential diagnosis. Brain and spinal cord enhancement is related to both intravascular and extravascular contrast material. Extraaxial enhancing lesions include primary neoplasms (meningioma), granulomatous disease (sarcoid), and metastases (which often manifest as mass lesions). Linear pachymeningeal (dura-arachnoid) enhancement occurs after surgery and with spontaneous intracranial hypotension. Leptomeningeal (pia-arachnoid) enhancement is present in meningitis and meningoencephalitis. Superficial gyral enhancement is seen after reperfusion in cerebral ischemia, during the healing phase of cerebral infarction, and with encephalitis. Nodular subcortical lesions are typical for hematogenous dissemination and may be neoplastic (metastases) or infectious (septic emboli). Deeper lesions may form rings or affect the ventricular margins. Ring enhancement that is smooth and thin is typical of an organizing abscess, whereas thick irregular rings suggest a necrotic neoplasm. Some low-grade neoplasms are "fluid-secreting," and they may form heterogeneously enhancing lesions with an incomplete ring sign as well as the classic "cyst-with-nodule" morphology. Demyelinating lesions, including both classic multiple sclerosis and tumefactive demyelination, may also create an open ring or incomplete ring sign. Thick and irregular periventricular enhancement is typical for primary central nervous system lymphoma. Thin enhancement of the ventricular margin occurs with infectious ependymitis. Understanding the classic patterns of lesion enhancement--and the radiologic-pathologic mechanisms that produce them--can improve image assessment and differential diagnosis.
Technique for Mini-open Decompression of Chiari Type I Malformation in Adults.
The technique for decompression of Chiari type I malformation relies on open exposure of craniocervical junction for suboccipital craniectomy and upper cervical laminectomy with or without duraplasty. There is no detailed technical report of a minimally invasive approach for Chiari decompression in adults. To describe a mini-open technique for decompression of Chiari type I malformation (including duraplasty) in adults. Six consecutive adult patients with symptomatic Chiari type I malformation underwent decompression through a 3 to 4 cm midline incision via a speculum retractor. All patients underwent a limited suboccipital craniectomy and C1 laminectomy with an ultrasonic bone scalpel. All patients underwent duraplasty with a synthetic dural substitute. In the 2 patients with syringomyelia, the arachnoid was opened and intradural dissection was carried out. In the remaining 4 patients, the arachnoid was left intact. All operations were completed successfully through the mini-open exposure. Mean surgery time, blood loss, and length of stay were 114 min, 55 mL, and 1.3 days, respectively. Mean follow-up was 13.2 months (range 9-18). All patients had excellent clinical outcomes as defined by scores of 15 (3 patients) or 16 (3 patients) on Chicago Chiari Outcome Scale. There were no neurological complications or cerebrospinal fluid leaks. Postop computed tomography revealed good boney decompression. In the 2 patients with syringomyelia, MRI at 6 months revealed resolution of the syrinx. Decompression of Chiari type I malformation in adults can be performed safely and effectively through the mini-open exposure described in this report. Copyright © 2017 by the Congress of Neurological Surgeons
Split-brain phenomena in anterior communicating artery aneurysm rupture: A case report.
Korsakova, Natalya; Liebson, Elizabeth; Moskovich, Lena
In 1976, a patient with an anterior communicating artery aneurysm (ACoAA) rupture (diagnosed on angiography) and sub-arachnoid hemorrhage (SAH) underwent serial neuropsychological testing revealing a classical anterior cerebral artery (ACA) spasm picture with severe anterograde amnesia of Korsakoff's type and dysexecutive syndrome. In addition, the patient demonstrated impaired hemispheric interaction with alien hand syndrome, dyscopia-dysgraphia, complete left ear neglect, and other, more complex, split-brain phenomena. He was evaluated by A. R. Luria in 1976. Following surgery the patient demonstrated gradual improvement. © 2017 The Institute of Psychology, Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.
Foramen Magnum Meningioma: a Case Report and Review of Literature.
Jurinovic, Pavao; Bulicic, Ana Repic; Marcic, Marino; Mise, Nikolina Ivica; Titlic, Marina; Suljic, Enra
Meningiomas are slow-growing benign tumors that arise at any location where arachnoid cells reside. Although meningiomas account for a sizable proportion of all primary intracranial neoplasms (14.3-19%), only 1.8 to 3.2% arise at the foramen magnum. Their indolent development at the craniocervical junction makes clinical diagnosis complex and often leads to a long interval between onset of symptoms and diagnosis. We report a case of a 79-year-old male patient, presented with ataxia and sense of threatening fainting during verticalization. Magnetic resonance imaging revealed the presence of meningioma in the right side of craniospinal junction.
Potentially stress-induced acute splanchnic segmental arterial mediolysis with a favorable spontaneous outcome.
Belbezier, Aude; Sarrot-Reynauld, Françoise; Thony, Frédéric; Tahon, Florence; Heck, Olivier; Bouillet, Laurence
A 62-year-old woman presented with hemithoracic anesthesia and acute abdominal pain following a violent psychological stress. Magnetic resonance imaging showed a thoracic hematoma with arachnoiditis of the spinal cord. Tomography revealed a typical aspect of segmental arterial mediolysis with multiple aneurysms and stenoses of the splanchnic arteries, confirmed by abdominal arteriography. There was no argument for hereditary, traumatic, atherosclerotic, infectious, or inflammatory arterial disease. Segmental arterial mediolysis was diagnosed on the basis of the radiologic data and probably involved both medullary and splanchnic arteries. The patient spontaneously recovered and was in good health 18 months later.
Idiopathic thoracic transdural intravertebral spinal cord herniation
Turel, Mazda K; Wewel, Joshua T; Kerolus, Mena G; O'Toole, John E
Idiopathic spinal cord herniation is a rare and often missed cause of thoracic myelopathy. The clinical presentation and radiological appearance is inconsistent and commonly confused with a dorsal arachnoid cyst and often is a misdiagnosed entity. While ventral spinal cord herniation through a dural defect has been previously described, intravertebral herniation is a distinct entity and extremely rare. We present the case of a 70-year old man with idiopathic thoracic transdural intravertebral spinal cord herniation and discuss the clinico-radiological presentation, pathophysiology and operative management along with a review the literature of this unusual entity. PMID:29021685
Melanotic neuroectodermal tumor of the neurocranium in infancy.
Walsh, J W; Strand, R D
Melanotic neuroectodermal tumors of the neurocranium are a rare but life-threatening disorder of infancy. 11 previously reported cases are reviewed in terms of clinical presentation, radiological diagnosis, and management. A twelfth case, a 4-month-old infant who developed three discrete sites of tumor unilaterally in the neurocranium is presented. Several hypotheses for the mechanism of formation of these tumors are reviewed. The authors propose that the mechanism of formation involves a dysontogenesis of neural crest tissue and that these tumors form, at least in part, from fragments of melanin-containing arachnoid villi which are displaced during embryonic development.
[Electron microscopy of the lesions produced in the human dura mater by Quincke beveled and Whitacre needles].
Reina, M A; López-García, A; de Andrés-Ibáñez, J A; Dittmann, M; Cascales, M R; del Caño, M C; Daneri, J; Zambrano, O
Comparisons of Quincke needles and non traumatic "pencil point" needles in recent years have reported lower rates of post dural puncture headache using the later type. Our new understanding of the morphology of the human dura mater motivated us to study dural lesions caused by the Whitacre 25 G and Quincke 26 G needles, using scanning electron microscopy with the aim of determining whether there is an anatomic basis for the different outcomes. The dura mater from three fresh cadavers of individuals aged 65, 70 and 72 years were punctured 40 times at an angle of 90 degrees each time. The Whitacre 25 G needle was used for 20 punctures and the Quincke 26 G needle was used for the other 20. Half the punctures were performed with the bevel in the parallel alignment and the other half with the bevel perpendicular to the spinal column. Fifteen min after causing the punctures, specimens were fixed in solutions of glutaraldehyde phosphate buffer and dehydrated in acetone. After critical point removal of the acetone, after the specimens were treated with carbon and metallized with gold. The lesions were examined externally and internally and expressed as the ratio of area of lesion to diameter of the needle that had caused them. Whitacre needle: each lesion consisted in the superimposition of multiple damaged layers that started to close individually. After 15 min the outermost layers were 90% closed and the innermost ones had closed entirely. Layers in the arachnoid surface of the dura mater had closed from 86 to 88%, while deeper layers in the thick part had closed 97 to 98%. Quincke needle: lesions were V-shaped or half-moon shaped, much like the opening formed by a can opener, on both the external and internal surfaces. Alignment of the bevel of the needle parallel to the spinal column did not lead to a different shape of puncture. After 15 min the lesions had closed 94 to 95% on the epidural surface and 95 to 96% on the arachnoid side, a difference attributable to the
SU-E-I-67: Arachnoid Cysts: The Role of the BLADE Technique
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mavroidis, P; Vlachopoulou, A; Kostopoulos, S
Purpose: The purpose of this study is first to show the extent by which BLADE sequences can reduce all the image artifacts and second to verify that the usefulness of this technique in certain pathological conditions is significant. Methods: In this study, fourteen consecutive patients (5 females, 9 males), who routinely underwent MRI brain examination, between 2010–2014, were selected. The applied routine protocols for brain MR examination included the following sequences: 1) T2-W FLAIR axial; 2) T2-W TSE axial; 3) T2*-W axial, 4) T1-W TSE sagittal; 5) DWI-W axial; 6) T1-W TSE axial; 7) T1-W TSE axial+contrast. In cases ofmore » cystic tumors, the T2-W FLAIR BLADE sequence was added to the protocol. All the images were evaluated independently at two separate settings with 3 weeks interval by two radiologists. The radiologists also evaluated the presence of image artifacts (motion, flow, chemical shift, Gibbs ringing). To evaluate the size of the cyst, the two radiologists compared the two techniques (conventional and BLADE) by assessing the extent of the divergence in the measurements of the cysts. Results: Regarding the extent of the cyst size, BLADE measurements were found to be more reliable than the conventional ones with the differences being statistically significant (p<0.01). The qualitative measurements indicated that the T2 FLAIR BLADE sequences were superior to the conventional T2 FLAIR with statistically significant differences (p<0.001) in the following characteristics: 1) overall image quality, 2) CSF nulling; 3) contrast at the pathology and its surrounding; 4) limits of the pathology; 5) motion artifacts; 6) flow artifacts; 7) chemical shift artifacts and 8) Gibbs ringing artifacts. Conclusion: BLADE sequence was found to decrease both flow artifacts in the temporal lobes and motion artifacts from the orbits and it is proposed for clinical use.« less
Stretching of roots contributes to the pathophysiology of radiculopathies.
Berthelot, Jean-Marie; Laredo, Jean-Denis; Darrieutort-Laffite, Christelle; Maugars, Yves
To perform a synthesis of articles addressing the role of stretching on roots in the pathophysiology of radiculopathy. Review of relevant articles on this topic available in the PubMed database. An intraoperative microscopy study of patients with sciatica showed that in all patients the hernia was adherent to the dura mater of nerve roots. During the SLR (Lasègue's) test, the limitation of nerve root movement occurs by periradicular adhesive tissue, and temporary ischemic changes in the nerve root induced by the root stretching cause transient conduction disturbances. Spinal roots are more frail than peripheral nerves, and other mechanical stresses than root compression can also induce radiculopathy, especially if they also impair intraradicular blood flow, or the function of the arachnoid villi intimately related to radicular veins. For instance arachnoiditis, the lack of peridural fat around the thecal sac, and epidural fibrosis following surgery, can all promote sciatica, especially in patients whose sciatic trunks also stick to piriformis or internus obturator muscles. Indeed, stretching of roots is greatly increased by adherence at two levels. As excessive traction of nerve roots is not shown by imaging, many physicians have unlearned to think in terms of microscopic and physiologic changes, although nerve root compression in the lumbar MRI is lacking in more than 10% of patients with sciatica. It should be reminded that, while compression of a spinal nerve root implies stretching of this root, the reverse is not true: stretching of some roots can occur without any visible compression. Copyright © 2017 Société française de rhumatologie. Published by Elsevier SAS. All rights reserved.
Anatomy and Pathophysiology of Spinal Cord Injury Associated With Regional Anesthesia and Pain Medicine: 2015 Update.
Neal, Joseph M; Kopp, Sandra L; Pasternak, Jeffrey J; Lanier, William L; Rathmell, James P
In March 2012, the American Society of Regional Anesthesia and Pain Medicine convened its second Practice Advisory on Neurological Complications in Regional Anesthesia and Pain Medicine. This update is based on the proceedings of that conference and relevant information published since its conclusion. This article updates previously described information on the pathophysiology of spinal cord injury and adds new material on spinal stenosis, blood pressure control during neuraxial blockade, neuraxial injury subsequent to transforaminal procedures, cauda equina syndrome/local anesthetic neurotoxicity/arachnoiditis, and performing regional anesthetic or pain medicine procedures in patients concomitantly receiving general anesthesia or deep sedation. Recommendations are based on extensive review of research on humans or employing animal models, case reports, pathophysiology research, and expert opinion. The pathophysiology of spinal cord injury associated with regional anesthetic techniques is reviewed in depth, including that related to mechanical trauma from direct needle/catheter injury or mass lesions, spinal cord ischemia or vascular injury from direct needle/catheter trauma, and neurotoxicity from local anesthetics, adjuvants, or antiseptics. Specific recommendations are offered that may reduce the likelihood of spinal cord injury associated with regional anesthetic or interventional pain medicine techniques. The practice advisory's recommendations may, in select cases, reduce the likelihood of injury. However, many of the described injuries are neither predictable nor preventable based on our current state of knowledge. Since publication of initial recommendations in 2008, new information has enhanced our understanding of 5 specific entities: spinal stenosis, blood pressure control during neuraxial anesthesia, neuraxial injury subsequent to transforaminal techniques, cauda equina syndrome/local anesthetic neurotoxicity/arachnoiditis, and performing regional
Foramen Magnum Meningioma: a Case Report and Review of Literature
Jurinovic, Pavao; Bulicic, Ana Repic; Marcic, Marino; Mise, Nikolina Ivica; Titlic, Marina; Suljic, Enra
Introduction: Meningiomas are slow-growing benign tumors that arise at any location where arachnoid cells reside. Although meningiomas account for a sizable proportion of all primary intracranial neoplasms (14.3–19%), only 1.8 to 3.2% arise at the foramen magnum. Their indolent development at the craniocervical junction makes clinical diagnosis complex and often leads to a long interval between onset of symptoms and diagnosis. Case report: We report a case of a 79-year-old male patient, presented with ataxia and sense of threatening fainting during verticalization. Magnetic resonance imaging revealed the presence of meningioma in the right side of craniospinal junction. PMID:27041817
Visualization of an actively bleeding cortical vessel into the subdural space by CT angiography.
Dalfino, John C; Boulos, Alan S
Spontaneous subdural hematomas of arterial origin are rare with only a few published case reports in the literature. In the CT era, vessel imaging of extra-axial hematomas is not commonly performed. In this case report we present a patient with a large, spontaneous acute subdural hematoma that demonstrated active contrast extravasation from a small cortical vessel on CT angiography. During surgical evacuation the vessel was confirmed to be a small cortical artery that was bulging through the arachnoid membrane and bleeding into the subdural space. The historical, radiographic, and clinical aspects of this unusual cause of subdural hematoma are discussed. (c) 2010 Elsevier B.V. All rights reserved.
Lumbar subdural cerebrospinal fluid collection with acute cauda equina syndrome after posterior fossa decompression for Chiari malformation Type I: case report.
Darwish, Houssein A; Oldfield, Edward H
This report describes the circumstances of a patient with a cauda equina syndrome due to the development of a lumbar subdural CSF collection with ventral displacement of the cauda equina shortly following posterior fossa decompression for Chiari malformation Type I (CM-I). This unusual, but clinically significant, complication was successfully treated with percutaneous drainage of the extraarachnoid CSF collection. Although there are a few cases of intracranial subdural hygroma developing after surgery for CM-I, often attributed to a pinhole opening in the arachnoid, as far as the authors can determine, a spinal subdural hygroma associated with surgery for CM-I has not been recognized.
Management of acute, recurrent, and chronic meningitides in adults.
Cho, Tracey A; Venna, Nagagopal
Meningitis (inflammation of the pia, arachnoid, and sometimes dura) has diverse causes and presentations. Although viruses are the most common cause of acute meningitis, bacterial meningitides are more severe and important to exclude because morbidity and mortality are high. Chronic meningitis has a broader range of causes, including atypical bacteria, fungi, and noninfectious causes. Presentation is more insidious but, if untreated, significant damage or death may ensue. Recurrent meningitis has many of the same causes as chronic meningitis, but manifestations occur in discrete episodes. Distinguishing between acute, chronic, and recurrent meningitis is essential for proper diagnostic testing and treatment approaches. Copyright 2010 Elsevier Inc. All rights reserved.
Introduction: Intradural Spinal Surgery video supplement.
McCormick, Paul C
This Neurosurgical Focus video supplement contains detailed narrated videos of a broad range of intradural pathology such as neoplasms, including intramedullary, extramedullary, and dumbbell tumors, vascular malformations, functional disorders, and rare conditions that are often overlooked or misdiagnosed such as arachnoid cysts, ventral spinal cord herniation, and dorsal arachnoid web. The intent of this supplement is to provide meaningful educational and instructional content at all levels of training and practice. As such, the selected video submissions each provide a comprehensive detailed narrative description and coordinated video that contains the entire spectrum of relevant information including imaging, operative setup and positioning, and exposure, as well as surgical strategies, techniques, and sequencing toward the safe and effective achievement of the operative objective. This level of detail often necessitated a more lengthy video duration than is typically presented in oral presentations or standard video clips from peer reviewed publications. Unfortunately, space limitations precluded the inclusion of several other excellent video submissions in this supplement. While most videos in this supplement reflect standard operative approaches and techniques there are also submissions that describe innovative exposures and techniques that have expanded surgical options such as ventral approaches, stereotactic guidance, and minimally invasive exposures. There is some redundancy in both the topics and techniques both to underscore fundamental surgical principles as well as to provide complementary perspective from different surgeons. It has been my privilege to serve as guest editor for this video supplement and I would like to extend my appreciation to Mark Bilsky, Bill Krauss, and Sander Connolly for reviewing the large number submitted videos. Most of all, I would like to thank the authors for their skill and effort in the preparation of the outstanding
Three-dimensional constructive interference in steady-state magnetic resonance imaging in syringomyelia: advantages over conventional imaging.
Roser, Florian; Ebner, Florian H; Danz, Søren; Riether, Felix; Ritz, Rainer; Dietz, Klaus; Naegele, Thomas; Tatagiba, Marcos S
Neuroradiology has become indispensable in detecting the pathophysiology in syringomyelia. Constructive interference in steady-state (CISS) magnetic resonance (MR) imaging can provide superior contrast at the sub-arachnoid tissue borders. As this region is critical in preoperative evaluation, the authors hypothesized that CISS imaging would provide superior assessment of syrinx pathology and surgical planning. Based on records collected from a database of 130 patients with syringomyelia treated at the authors' institution, 59 patients were prospectively evaluated with complete neuroradiological examinations. In addition to routine acquisitions with FLAIR, T1- and T2-weighted, and contrast-enhanced MR imaging series, the authors obtained sagittal cardiac-gated sequences to visualize cerebrospinal fluid (CSF) pulsations and axial 3D CISS MR sequences to detect focal arachnoid webs. Statistical qualitative and quantitative evaluations of spinal cord/CSF contrast, spinal cord/CSF delineation, motion artifacts, and artifacts induced by pulsatile CSF flow were performed. The 3D CISS MR sequences demonstrated a contrast-to-noise ratio significantly better than any other routine imaging sequence (p < 0.001). Moreover, 3D CISS imaging can detect more subarachnoid webs and cavitations in the syrinx than T2-weighted MR imaging with less flow-void artifact. The limitation of 3D CISS imaging is a susceptibility to motion artifacts that can cause reduced spatial resolution. Lengthy acquisition times for axial segments can be reduced with multiplanar reconstruction of 3D CISS-generated sagittal images. Constructive interference in steady-state imaging is the MR sequence of choice in the preoperative evaluation of syringomyelia, allowing significantly higher detection rates of focal subarachnoid webs, whereas standard T2-weighted MR imaging shows turbulent CSF flow voids. Constructive interference in steady-state MR imaging enables the neurosurgeon to accurately identify cases
MRI features of growth hormone deficiency in children with short stature caused by pituitary lesions.
Xu, Chao; Zhang, Xinxian; Dong, Lina; Zhu, Bin; Xin, Tao
We verified the advantages of using magnetic resonance imaging (MRI) for improving the diagnostic quality of growth hormone deficiency (GHD) in children with short stature caused by pituitary lesions. Clinical data obtained from 577 GHD patients with short stature caused by pituitary lesions were retrospectively analyzed. There were 354 cases (61.3%) with anterior pituitary dysplasia; 45 cases (7.8%) of pituitary stalk interruption syndrome (PSIS); 15 cases (2.6%) of pituitary hyperplasia due to primary hypothyroidism; 38 cases (6.6%) of Rathke cleft cyst; 68 cases (11.8%) of empty sella syndrome; 16 cases (2.8%) of pituitary invasion from Langerhans cell histiocytosis; 2 cases (0.3%) of sellar regional arachnoid cyst and 39 cases (6.8%) of craniopharyngioma. MRI results showed that the height of anterior pituitary in patients was less than normal. Location, size and signals of posterior pituitary and pituitary stalk were normal in anterior pituitary dysplasia. In all cases pituitary hyperplasia was caused by hypothyroidism. MRI results showed that anterior pituitary was enlarged, and we detected upward apophysis and obvious homogeneous enhancement. There were no pituitary stalk interruption and abnormal signal. We also observed that after hormone replacement therapy the size of pituitary gland was reduced. Anterior pituitary atrophy was observed in Rathke cleft cyst, empty sella syndrome, sellar regional arachnoid cyst and craniopharyngioma. The microstructure of hypophysis and sellar region was studied with MRI. We detected pituitary lesions, and the characteristics of various pituitary diseases of GHD in children with short stature. It was concluded that in children with GHD caused by pituitary lesions, MRI was an excellent method for early diagnosis. This method offers clinical practicability and we believe it can be used for differential diagnosis and to monitor the therapeutic effects.
Biallelic PMS2 Mutation and Heterozygous DICER1 Mutation Presenting as Constitutional Mismatch Repair Deficiency With Corpus Callosum Agenesis: Case Report and Review of Literature.
Cheyuo, Cletus; Radwan, Walid; Ahn, Janice; Gyure, Kymberly; Qaiser, Rabia; Tomboc, Patrick
Constitutional mismatch repair deficiency syndrome is a cancer predisposition syndrome caused by autosomal recessive biallelic (homozygous) germline mutations in the mismatch repair genes (MLH1, MSH2, MSH6, and PMS2). The clinical spectrum includes neoplastic and non-neoplastic manifestations. We present the case of a 7-year-old boy who presented with T-lymphoblastic lymphoma and glioblastoma, together with non-neoplastic manifestations including corpus callosum agenesis, arachnoid cyst, developmental venous anomaly, and hydrocephalus. Gene mutation analysis revealed pathogenic biallelic mutations of PMS2 and heterozygous DICER1 variant predicted to be pathogenic. This report is the first to allude to a possible interaction of the mismatch repair system with DICER1 to cause corpus callosum agenesis.
Correlation between morphological MRI findings and specific diagnostic categories in fetal alcohol spectrum disorders.
Boronat, S; Sánchez-Montañez, A; Gómez-Barros, N; Jacas, C; Martínez-Ribot, L; Vázquez, E; Del Campo, M
Fetal alcohol spectrum disorders (FASD) include physical and neurodevelopmental abnormalities related to prenatal alcohol exposure. Some neuroimaging findings have been clearly related to FASD, including corpus callosum and cerebellar anomalies. However, detailed studies correlating with specific FASD categories, that is, the fetal alcohol syndrome (FAS), partial FAS (pFAS) and alcohol related neurodevelopmental disorders (ARND), are lacking. We prospectively performed clinical assessment and brain MR imaging to 72 patients with suspected FASD, and diagnosis was confirmed in 62. The most frequent findings were hypoplasia of the corpus callosum and/or of the cerebellar vermis. Additional findings were vascular anomalies, gliosis, prominent perivascular spaces, occipito-cervical junction and cervical vertebral anomalies, pituitary hypoplasia, arachnoid cysts, and cavum septum pellucidum. Copyright © 2016 Elsevier Masson SAS. All rights reserved.
'Subarachnoid cyst' after evacuation of chronic subdural hematoma: Case report of an unusual postoperative morbidity.
Sharon, Low Y Y; Wai Hoe, N G
Burr-hole drainage of chronic subdural hematomas are routine operative procedures done by neurosurgical residents. Common postoperative complications include acute epidural and/or subdural bleeding, tension pneumocephalus, intracranial hematomas and ischemic cerebral infarction. We report an interesting post-operative complication of a 'subarachnoid cyst' after burr-hole evacuation of a chronic subdural hematoma. The authors hypothesize that the 'cyst' is likely secondary to the splitting of the adjacent neomembrane within its arachnoid-brain interface by iatrogenic irrigation of the subdural space. Over time, this 'cyst' develops into an area of gliosis which eventually causes long-term scar epilepsy in the patient. As far as we are aware, this is the first complication of such a 'subarachnoid cyst' post burr-hole drainage reported in the literature.
Management of Paradoxical Response in Pediatric Tubercular Meningitis with Methylprednisolone
Nema, Nitin; Verma, Abha; Singh, Kuldeep; Mehar, Virendra
Paradoxical response to anti-tubercular drugs remains a diagnostic dilemma. In India where tuberculosis is quite prevalent, paradoxical response to anti-tubercular treatment (ATT) is either misdiagnosed or under-diagnosed. We report two cases of optochiasmatic arachnoiditis due to paradoxical response in children suffering from tuberculous meningitis. Visual acuity was recorded as no light perception in all eyes of both patients while they were taking 4-drug ATT (isoniazid, rifampicin, pyrazinamide and ethambutol). However their systemic conditions did not worsen. They were treated with intravenous methylprednisolone for five days followed by systemic corticosteroids on a tapering dose for four weeks along with ATT. This case report highlights the importance of early recognition of this sight-threatening complication and timely, effective treatment to prevent permanent blindness. PMID:24791114
Cranial nerve monitoring during subpial dissection in temporomesial surgery.
Ortler, Martin; Fiegele, Thomas; Walser, Gerald; Trinka, Eugen; Eisner, Wilhelm
Cranial nerves (CNs) crossing between the brainstem and skull base at the level of the tentorial hiatus may be at risk in temporomesial surgery involving subpial dissection and/or tumorous growth leading to distorted anatomy. We aimed to identify the surgical steps most likely to result in CN damage in this type of surgery. Electromyographic responses obtained with standard neuromonitoring techniques and a continuous free-running EMG were graded as either contact activity or pathological spontaneous activity (PSA) during subpial resection of temporomesial structures in 16 selective amygdalohippocampectomy cases. Integrity of peripheral motor axons was tested by transpial/transarachnoidal electrical stimulation while recording compound muscle action potentials from distal muscle(s). Continuous EMG showed pathological activity in five (31.2%) patients. Nine events with PSA (slight activity, n = 8; strong temporary activity, n = 1) were recorded. The oculomotor nerve was involved three times, the trochlear nerve twice, the facial nerve once, and all monitored nerves on three occasions. Surgical maneuvers associated with PSA were the resection of deep parts of the hippocampus and parahippocampal gyrus (CN IV, twice; CN III, once), lining with or removing cotton patties from the resection cavity (III, twice; all channels, once) and indirect exertion of tension on the intact pia/arachnoid of the uncal region while mobilizing the hippocampus and parahippocampal gyrus en bloc (all channels, once; III, once). CMAPs were observed at 0.3 mA in two patients and at 0.6 mA in one patient, and without registering the exact amount of intensity in three patients. The most dangerous steps leading to cranial nerve damage during mesial temporal lobe surgery are the final stages of the intervention while the resection is being completed in the deep posterior part and the resection cavity is being lined with patties. Distant traction may act on nerves crossing the tentorial
Conjunctival oedema as a potential objective sign of intracranial hypertension: a short illustrated review and three case reports.
Toalster, Nicholas; Jeffree, Rosalind L
Periorbital and conjunctival oedema has been reported anecdotally by patients with raised intracranial pressure states. We present three clinical cases of this phenomenon and discuss the current evidence for pathways by which cerebrospinal fluid (CSF) drains in relation to conjunctival oedema. We reviewed the available literature using PubMed, in regards to conjunctival oedema as it relates to intracranial hypertension, and present the clinical history, radiology and orbital photographs of three cases we have observed. Only one previous publication has linked raised intracranial pressure (ICP) to conjuctival oedema. The weight of evidence supports the observation that the majority of CSF drains along the cranial nerves as opposed to via the arachnoid projections. Conjunctival oedema may be a clinical manifestation of CSF draining via the optic nerve in elevated ICP states.
‘Subarachnoid cyst’ after evacuation of chronic subdural hematoma: Case report of an unusual postoperative morbidity
Sharon, Low Y. Y.; Wai Hoe, NG
Burr-hole drainage of chronic subdural hematomas are routine operative procedures done by neurosurgical residents. Common postoperative complications include acute epidural and/or subdural bleeding, tension pneumocephalus, intracranial hematomas and ischemic cerebral infarction. We report an interesting post-operative complication of a ‘subarachnoid cyst’ after burr-hole evacuation of a chronic subdural hematoma. The authors hypothesize that the ‘cyst’ is likely secondary to the splitting of the adjacent neomembrane within its arachnoid-brain interface by iatrogenic irrigation of the subdural space. Over time, this ‘cyst’ develops into an area of gliosis which eventually causes long-term scar epilepsy in the patient. As far as we are aware, this is the first complication of such a ‘subarachnoid cyst’ post burr-hole drainage reported in the literature. PMID:27366276
Morphological manifestations of the Dandy-Walker syndrom in female members of a family.
Titlić, Marina; Alfirević, Stanko; Kolić, Krešimir; Soldo, Anamarija; Tripalol, Ana Batoš
The Dandy-Walker syndrome (DWS) is a hereditary disorder, appearing somewhat more frequently in women. The most important characteristics of the DWS are the lack of the cerebellar vermis, varying from a partial lack to a complete agenesis, and enlargement of the cerebrospinal spaces, especially in the fourth ventricle. The above mentioned morphological changes clinically manifest in ataxia, increased intracranial pressure and hydrocephalus. Here is presented a family with DWS, where the disease is contracted only by female members, in two generations, whereas no signs of DWS have been noticed in male family members. DWS is clinically manifested from early childhood to middle age, with the morphological changes varying from hypoplastic cerebellar vermis to widening of the brain ventricles and hydrocephalus and arachnoid cyst in the occipital part.
Redescription of four species of Mehdiella from Testudinidae, with a key to the species and discussion on the relationships among the species of this genus.
Bouamer, S; Morand, S; Kara, M
Four species of the genus Mehdiella Seurat, 1918 are redescribed: M. cristata Petter, 1966 and M. stylosa dollfusi Petter, 1966, parasite of Pyxix arachnoides Bell, 1827 from Madagascar, M. s. stylosa (Thapar, 1925) and M. uncinata (Drasche, 1884), parasite of Testudo graeca Linneaus, 1758, Testudo hermanni Gmelin, 1789 and Testudo horsfieldii (Gray, 1844) from Palaearctic region. Light microscopy and scanning electron microscopy (SEM) studies revealed new informations on the morphology of these species. On the basis of this morphological study, the sub-species Mehdiella stylosa dollfusi and M. s. stylosa are raised to level of species. The position of Mehdiella cristata among the species of the genus Mehdiella and the relationships among the species of the genus Mehdiella are discussed. A key to the eight valid species Mehdiella is given.
Amphetamine and environmentally induced hyperthermia differentially alter the expression of genes regulating vascular tone and angiogenesis in the meninges and associated vasculature.
Thomas, Monzy; George, Nysia I; Patterson, Tucker A; Bowyer, John F
An amphetamine (AMPH) regimen that does not produce a prominent blood-brain barrier breakdown was shown to significantly alter the expression of genes regulating vascular tone, immune function, and angiogenesis in vasculature associated with arachnoid and pia membranes of the forebrain. Adult-male Sprague-Dawley rats were given either saline injections during environmentally-induced hyperthermia (EIH) or four doses of AMPH with 2 h between each dose (5, 7.5, 10, and 10 mg/kg d-AMPH, s.c.) that produced hyperthermia. Rats were sacrificed either 3 h or 1 day after dosing, and total RNA and protein was isolated from the meninges, arachnoid and pia membranes, and associated vasculature (MAV) that surround the forebrain. Vip, eNos, Drd1a, and Edn1 (genes regulating vascular tone) were increased by either EIH or AMPH to varying degrees in MAV, indicating that EIH and AMPH produce differential responses to enhance vasodilatation. AMPH, and EIH to a lesser extent, elicited a significant inflammatory response at 3 h as indicated by an increased MAV expression of cytokines Il1b, Il6, Ccl-2, Cxcl1, and Cxcl2. Also, genes related to heat shock/stress and disruption of vascular homeostasis such as Icam1 and Hsp72 were also observed. The increased expression of Ctgf and Timp1 and the decreased expression of Akt1, Anpep, and Mmp2 and Tek (genes involved in stimulating angiogenesis) from AMPH exposure suggest that angiogenesis was arrested or disrupted in MAV to a greater extent by AMPH compared to EIH. Alterations in vascular-related gene expression in the parietal cortex and striatum after AMPH were less in magnitude than in MAV, indicating less of a disruption of vascular homeostasis in these two regions. Changes in the levels of insulin-like growth factor binding proteins Igfbp1, 2, and 5 in MAV, compared to those in striatum and parietal cortex, imply an interaction between these regions to regulate the levels of insulin-like growth factor after AMPH damage. Thus, the
Dandy-Walker syndrome studied by computed tomography and pneumoencephalography
DOE Office of Scientific and Technical Information (OSTI.GOV)
Masdeu, J.C.; Dobben, G.D.; Azar-Kia, B.
Based on air studies, some authors have disputed the ability of computed tomography (CT) to diagnose posterior fossa cysts. The authors correlated the pneumoencephalographic, CT, and pathological findings in 4 patients with classic Dandy-Walker syndrome. Three cases had been misdiagnosed as retrocerebellar arachnoid cysts because the fourth ventricle was incorrectly considered normal on brow-up or erect air studies, reflecting the inability of such studies to evaluate an agenetic vermis and deficient posterior medullary velum which are characteristic of Dandy-Walker malformation. Careful correlation with autopsy findings showed that even with complete agenesis of the inferior vermis, if the slit between themore » cerebellar hemispheres is narrow, the fourth ventricle could be misinterpreted as normal on pneumoencephalography and sagittal CT. Radionuclide studies, a small amount of air, or metrizamide may be needed to determine whether the cyst communicates with the subarachnoid space.« less
Repair of Spontaneous Cerebrospinal Fluid Otorrhea from Defect of Middle Cranial Fossa
Goh, Young Bum; Han, Chi-Sung
Spontaneous cerebrospinal fluid (CSF) otorrhea is defined as CSF otorrhea where there are no identifiable causes including previous trauma, surgery, infection, neoplasm or congenital anomaly. The condition is rare. The origin of CSF leak is commonly a defect in the tegmen of the middle cranial fossa. The pathophysiology of spontaneous CSF otorrhea is unclear. Two theories of the etiology of bony defects of the temporal bone are the congenital bony defect theory and arachnoid granulation theory. The authors experienced a case of a 49-year-old female patient admitted with the complaint of persistent right ear fullness. Computed tomography revealed a large defect of the middle fossa and suspicious CSF otorrhea through the defect of tegmen tympani. Repair was successful with multiple bone chips using the transmastoid approach. The postoperative course was good and there has been no recurrence of the CSF leakage. PMID:24653924
Minimally invasive computer-assisted stereotactic fenestration of an aqueductal cyst: case report.
Fonoff, E T; Gentil, A F; Padilha, P M; Teixeira, M J
Current advances in frame modeling and computer software allow stereotactic procedures to be performed with great accuracy and minimal risk of neural tissue or vascular injury. In this report we associate a previously described minimally invasive stereotactic technique with state-of-the-art 3D computer guidance technology to successfully treat a 55-year-old patient with an arachnoidal cyst obstructing the aqueduct of Sylvius. We provide detailed technical information and discuss how this technique deals with previous limitations for stereotactic manipulation of the aqueductal region. We further discuss current advances in neuroendoscopy for treating obstructive hydrocephalus and make comparisons with our proposed technique. We advocate that this technique is not only capable of treating this pathology but it also has the advantages to enable reestablishment of physiological CSF flow thus preventing future brainstem compression by cyst enlargement. (c) Georg Thieme Verlag KG Stuttgart . New York.
Test of the 'glymphatic' hypothesis demonstrates diffusive and aquaporin-4-independent solute transport in rodent brain parenchyma.
Smith, Alex J; Yao, Xiaoming; Dix, James A; Jin, Byung-Ju; Verkman, Alan S
Transport of solutes through brain involves diffusion and convection. The importance of convective flow in the subarachnoid and paravascular spaces has long been recognized; a recently proposed 'glymphatic' clearance mechanism additionally suggests that aquaporin-4 (AQP4) water channels facilitate convective transport through brain parenchyma. Here, the major experimental underpinnings of the glymphatic mechanism were re-examined by measurements of solute movement in mouse brain following intracisternal or intraparenchymal solute injection. We found that: (i) transport of fluorescent dextrans in brain parenchyma depended on dextran size in a manner consistent with diffusive rather than convective transport; (ii) transport of dextrans in the parenchymal extracellular space, measured by 2-photon fluorescence recovery after photobleaching, was not affected just after cardiorespiratory arrest; and (iii) Aqp4 gene deletion did not impair transport of fluorescent solutes from sub-arachnoid space to brain in mice or rats. Our results do not support the proposed glymphatic mechanism of convective solute transport in brain parenchyma.
Chlorhexidine droplet splash from a skin preparation gallipot: effect of height of pouring.
Evans, L; Cunningham, M; Tilakaratna, P
Chlorhexidine contamination of equipment used in central neuraxial anaesthesia has been implicated in causing adhesive arachnoiditis. We measured the extent of chlorhexidine splash during pouring into a gallipot (antiseptic skin preparation container) from heights of 5 cm, 10 cm, 15 cm and 20 cm. Twenty experiments were performed at each height. Measurements made up to a horizontal distance of 40 cm radius from the gallipot showed a median (IQR [range]) maximum spread of splash droplets ≥ 2 mm diameter of 26.2 (10.2-36.4 [0-40]) cm. The 40-cm radius measurement area was divided into 5-cm-wide zones to assess spread. At pouring heights of 15 cm and 20 cm, all zones were contaminated. These results demonstrate that pouring chlorhexidine into a gallipot generates significant splash, and we recommend that this should be avoided near equipment used for neuraxial anaesthesia. © 2013 The Association of Anaesthetists of Great Britain and Ireland.
Anatomy and development of the meninges: implications for subdural collections and CSF circulation.
Mack, Julie; Squier, Waney; Eastman, James T
The dura is traditionally viewed as a supportive fibrous covering of the brain containing the dural venous sinuses but otherwise devoid of vessels and lacking any specific function. However, review of the embryology and anatomy reveals the dura to be a complex, vascularized and innervated structure, not a simple fibrous covering. The dura contains an inner vascular plexus that is larger in the infant than in the adult, and this plexus likely plays a role in CSF absorption. This role could be particularly important in the infant whose arachnoid granulations are not completely developed. Although subdural hemorrhage is frequently traumatic, there are nontraumatic conditions associated with subdural hemorrhage, and the inner dural plexus is a likely source of bleeding in these nontraumatic circumstances. This review outlines the development and age-specific vascularity of the dura and offers an alternative perspective on the role of the dura in homeostasis of the central nervous system.
Test of the 'glymphatic' hypothesis demonstrates diffusive and aquaporin-4-independent solute transport in rodent brain parenchyma
Yao, Xiaoming; Dix, James A; Jin, Byung-Ju
Transport of solutes through brain involves diffusion and convection. The importance of convective flow in the subarachnoid and paravascular spaces has long been recognized; a recently proposed ‘glymphatic’ clearance mechanism additionally suggests that aquaporin-4 (AQP4) water channels facilitate convective transport through brain parenchyma. Here, the major experimental underpinnings of the glymphatic mechanism were re-examined by measurements of solute movement in mouse brain following intracisternal or intraparenchymal solute injection. We found that: (i) transport of fluorescent dextrans in brain parenchyma depended on dextran size in a manner consistent with diffusive rather than convective transport; (ii) transport of dextrans in the parenchymal extracellular space, measured by 2-photon fluorescence recovery after photobleaching, was not affected just after cardiorespiratory arrest; and (iii) Aqp4 gene deletion did not impair transport of fluorescent solutes from sub-arachnoid space to brain in mice or rats. Our results do not support the proposed glymphatic mechanism of convective solute transport in brain parenchyma. PMID:28826498
Risk factors associated with subdural hygroma after decompressive craniectomy in patients with traumatic brain injury : a comparative study.
Jeon, Sei Woong; Choi, Jong Hun; Jang, Tae Won; Moon, Seung-Myung; Hwang, Hyung-Sik; Jeong, Je Hoon
Subdural hygroma (SDG) is a complication occurring after head trauma that may occur secondary to decompressive craniectomy (DC). However, the mechanism underlying SDG formation is not fully understood. Also, the relationship between the operative technique of DC or the decompressive effect and the occurrence and pathophysiology of SDG has not been clarified. Purpose of this study was to investigate the risk factors of SDG after DC in our series. From January 2004 to December 2008, DC was performed in 85 patients who suffered from traumatic brain injury. We retrospectively reviewed the clinical and radiological features. For comparative analysis, we divided the patients into 2 groups : one group with SDG after craniectomy (19 patients; 28.4% of the total sample), the other group without SDG (48 patients; 71.6%). The risk factors for developing SDG were then analyzed. The mean Glasgow Outcome Scale (GOS) scores at discharge of the groups with and without SDG were 2.8 and 3.1, respectively (p<0.0001). Analysis of radiological factors showed that a midline shift in excess of 5 mm on CT scans was present in 19 patients (100%) in the group with SDG and in 32 patients (66.7%) in the group without SDG (p<0.05). An accompanying subarachnoid hemorrhage (SAH) was seen in 17 patients (89.5%) in the group with SDG and in 29 patients (60.4%) in the group without SDG (p<0.05). Delayed hydrocephalus accompanied these findings in 10 patients (52.6%) in the group with SDG, versus 5 patients (10.4%) in the group without SDG (p<0.05). On CT, compression of basal cisterns was observed in 14 members (73.7%) in the group with SDG and in 18 members of the group without SDG (37.5%) (p<0.007). Furthermore, tearing of the arachnoid membrane, as observed on CT, was more common in all patients in the group with SDG (100%) than in the group without SDG (31 patients; 64.6%) (p<0.05). GOS showed statistically significant difference in the clinical risk factors for SDG between the group with SDG
An in vitro study of dural lesions produced by 25-gauge Quincke and Whitacre needles evaluated by scanning electron microscopy.
Reina, M A; de Leon-Casasola, O A; Lopez, A; De Andres, J; Martin, S; Mora, M
external aspect (epidural surface) and 0.034 mm2 (CI 95%, 0.018 to 0.051) in the internal aspect (arachnoid surface) of the dural sac. The area of the lesions produced by the 25-gauge Whitacre needles was 0.026 mm2 (CI 95%, 0.019 to 0.032) and 0.030 mm2 (CI 95%, 0.025 to 0.036) in the external and internal surfaces of the dural sac, respectively. There were no significant differences in the cross-sectional areas of the punctures produced by the 25-gauge Whitacre or 25-gauge Quincke needles. Moreover, with Quincke needles the dural lesions closed in an 88.3% (CI 95%, 86.3 to 92.4) and 82.7% (CI 95%, 74.1 to 90.9) of their original sizes in the epidural and arachnoid surfaces, respectively. With Whitacre needles, the closure occurred in an 86.8% (CI 95%, 83.8 to 90.3) and 84.8% (CI 95% 81.7 to 87.3) in the dural and arachnoid surfaces, respectively. However, there were differences in the morphology of the lesions. The Whitacre needles produced coarse lesions with significant destruction in the dura's fibers while the Quincke needles produced a 'U'-shaped lesion (flap) that mimics the opened lid of a tin can, regardless of the tip's direction. The needles produced lesions in the dura with different morphology and characteristics. Lesions with the Quincke needles resulted in a clean-cut opening in the dural membrane while the Whitacre needle produced a more traumatic opening with tearing and severe disruption of the collagen fibers. Thus, we hypothesized that the lower incidence of PDPH seen with the Whitacre needles may be explained, in part, by the inflammatory reaction produced by the tearing of the collagen fibers after dural penetration. This inflammatory reaction may result in a significant edema which may act as a plug limiting the leakage of cerebrospinal fluid.
Aneurysmal SubArachnoid Hemorrhage—Red Blood Cell Transfusion And Outcome (SAHaRA): a pilot randomised controlled trial protocol
English, Shane W; Fergusson, D; Chassé, M; Lauzier, F; Griesdale, D; Algird, A; Kramer, A; Tinmouth, A; Lum, C; Sinclair, J; Marshall, S; Dowlatshahi, D; Boutin, A; Pagliarello, G; McIntyre, L A
Introduction Anaemia is common in aneurysmal subarachnoid haemorrhage (aSAH) and is a potential critical modifiable factor affecting secondary injury. Despite physiological evidence and management guidelines that support maintaining a higher haemoglobin level in patients with aSAH, current practice is one of a more restrictive approach to transfusion. The goal of this multicentre pilot trial is to determine the feasibility of successfully conducting a red blood cell (RBC) transfusion trial in adult patients with acute aSAH and anaemia (Hb ≤100 g/L), comparing a liberal transfusion strategy (Hb ≤100 g/L) with a restrictive strategy (Hb ≤80 g/L) on the combined rate of death and severe disability at 12 months. Methods Design This is a multicentre open-label randomised controlled pilot trial at 5 academic tertiary care centres. Population We are targeting adult aSAH patients within 14 days of their initial bleed and with anaemia (Hb ≤110 g/L). Randomisation Central computer-generated randomisation, stratified by centre, will be undertaken from the host centre. Randomisation into 1 of the 2 treatment arms will occur when the haemoglobin levels of eligible patients fall to ≤100 g/L. Intervention Patients will be randomly assigned to either a liberal (threshold: Hb ≤100 g/L) or a restrictive transfusion strategy (threshold: Hb ≤80 g/L). Outcome Primary: Centre randomisation rate over the study period. Secondary: (1) transfusion threshold adherence; (2) study RBC transfusion protocol adherence; and (3) outcome assessment including vital status at hospital discharge, modified Rankin Score at 6 and 12 months and Functional Independence Measure and EuroQOL Quality of Life Scale scores at 12 months. Outcome measures will be reported in aggregate. Ethics and dissemination The study protocol has been approved by the host centre (OHSN-REB 20150433-01H). This study will determine the feasibility of conducting the large pragmatic RCT comparing 2 RBC transfusion strategies examining the effect of a liberal strategy on 12-month outcome following aSAH. Trial registration number NCT02483351; Pre-results. PMID:27927658
Mechanisms of Hydrocephalus after Neonatal and Adult Intraventricular Hemorrhage
Strahle, Jennifer; Garton, Hugh J.L.; Maher, Cormac O.; Muraszko, Karin M.; Keep, Richard F.; Xi, Guohua
Intraventricular hemorrhage (IVH) is a cause of significant morbidity and mortality and is an independent predictor of a worse outcome in intracerebral hemorrhage (ICH) and germinal matrix hemorrhage (GMH). IVH may result in both injuries to the brain as well as hydrocephalus. This paper reviews evidence on the mechanisms and potential treatments for IVH-induced hydrocephalus. One frequently cited theory to explain hydrocephalus after IVH involves obliteration of the arachnoid villi by microthrombi with subsequent inflammation and fibrosis causing CSF outflow obstruction. Although there is some evidence to support this theory, there may be other mechanisms involved, which contribute to the development of hydrocephalus. It is also unclear whether the causes of acute and chronic hydrocephalus after hemorrhage occur via different mechanisms; mechanical obstruction by blood in the former, and inflammation and fibrosis in the latter. Management of IVH and strategies for prevention of brain injury and hydrocephalus are areas requiring further study. A better understanding of the pathogenesis of hydrocephalus after IVH, may lead to improved strategies to prevent and treat post-hemorrhagic hydrocephalus. PMID:23976902
Microneurosurgical management of temporal lobe epilepsy by amygdalohippocampectomy (AH) plus standard anterior temporal lobectomy (ATL): a report of our initial five cases in Bangladesh
Chowdhury, F H; Haque, M R; Islam, M S; Sarker, MH; Kawsar, KA; Sarker, AC
Patient presenting as a case of Temporal Lobe Epilepsy (TLE) are usually resistant to antiepileptic drugs and surgery is the treatment of choice. This type of epilepsy may be due to Mesial Temporal Sclerosis (MTS), tumors [i.e. low grade glioma, Arterio-Venous Malformation (AVM) etc], trauma, infection (Tuberculosis) etc. Here we report five cases of surgically treated TLE that were due to a MTS, MTS with arachnoid cyst, low grade ganglioglioma, high grade ganglioglioma and a tuberculoma in the department of neurosurgery, Dhaka Medical College Hospital and Islami Bank Central Hospital, Dhaka, Bangladesh from August 2009 to February 2010. In all cases the only presenting symptoms was complex partial seizures (psychomotor epilepsy) for which all underwent scalp EEG (Electro Encephalogram) and MRI (Magnetic Resonance Imaging) of Brain. All patients were managed by amygdalohippocampectomy plus standard anterior lobectomy. One patient with high grade ganglioglioma recurred within two months of operation and expired within five months. The rest of the cases are seizure and disease free till the last follow up. PMID:22028754
Spinal epidural neurostimulation for treatment of acute and chronic intractable pain: initial and long term results.
Richardson, R R; Siqueira, E B; Cerullo, L J
Spinal epidural neurostimulation, which evolved from dorsal column stimulation, has been found to be effective in the treatment of acute and chronic intractable pain. Urban and Hashold have shown that it is a safe, simplified alternative to dorsal column stimulation, especially because laminectomy is not required if the electrodes are inserted percutaneously. Percutaneous epidural neurostimulation is also advantageous because there can be a diagnostic trial period before permanent internalization and implantation. This diagnostic and therapeutic modality has been used in 36 patients during the past 3 years at Northwestern Memorial Hospital. Eleven of these patients had acute intractable pain, which was defined as pain of less than 1 year in duration. Initial postimplantation results from the 36 patients indicate that spinal epidural neurostimulation is most effective in treating the intractable pain of diabetes, arachnoiditis, and post-traumatic and postamputation neuroma. Long term follow-up, varying from 1 year to 3 years postimplantation in the 20 initially responding patients, indicates that the neurostimulation continues to provide significant pain relief (50% or greater) in a majority of the patients who experienced initial significant pain relief.
Spontaneous pneumocephalus after commercial air travel complicated by meningitis.
Javan, Ramin; Duszak, Richard; Eisenberg, Alan D; Eggers, Frank M
Pneumocephalus usually results from trauma, infection, neoplasm, or iatrogenic causes. Barotrauma-induced spontaneous pneumocephalus is extremely rare, usually seen in divers or occassionally with air travel. We report a case of a 61-yr-old female presenting with confusion, fever, and respiratory failure one day after developing sudden nausea, vomiting, and headache during descent on a commercial airliner. Pneumocephalus and meningitis were present on admission. Sinus computed tomography (CT) showed pansinusitis and a tiny bone defect in the posterior wall of the right sphenoid sinus, through which a cisternogram later showed free communication with the prepontine cistern. An orbital CT 2 yr earlier after a fall showed the bone defect, with no other areas of abnormality or fracture. After repair of defects by otolaryngology and appropriate antibiotics, she did well and was eventually discharged. Changes in aircraft cabin pressure likely resulted in rupture of dura and arachnoid layers beneath the pre-existing bony defect, predisposed by existing sinus disease. The pathophysiology, implications, and potential sources of spontaneous pneumocephalus, as well as risks of postcraniotomy and post-trauma air-travel, are discussed.
Minimally Invasive Treatment for a Sacral Tarlov Cyst Through Tubular Retractors.
Del Castillo-Calcáneo, Juan D; Navarro-Ramírez, Rodrigo; Nakhla, Jonathan; Kim, Eliana; Härtl, Roger
Tarlov cysts (TC) are focal dilations of arachnoid and dura mater of the spinal posterior nerve root sheath that appear as cystic lesions of the nerve roots typically in the lower spine, especially in the sacrum, which can cause radicular symptoms when they increase in size and compress the nerve roots. Different open procedures have been described to treat TCs, but no minimally invasive procedures have been described to effectively address this pathology. A 29-year-old woman presented with right lower extremity pain and weakness. A magnetic resonance imaging scan demonstrated a lumbosacral TC that protruded through the right L5-S1 foramina. Through a small laminotomy, cyst drainage followed by neck ligation using a Scanlan modified technique through tubular retractors was performed. The patient recovered full motor function within the first days postoperatively and showed no signs of relapse at 6-month follow-up. Minimally invasive spine surgery through tubular retractors can be safely performed for successful excision and ligation of TC using a Scanlan modified technique. Copyright © 2017 Elsevier Inc. All rights reserved.
[Successful management of neurosurgical procedures with continuous infusion of recombinant factor IX in a child with hemophilia B].
Yamamoto, Mariko; Nakadate, Hisaya; Iguchi, Umefumi; Masuda, Hiroshi; Sakai, Hirokazu; Ishiguro, Akira
This report describes the successful management of neurosurgical procedures with continuous infusion of recombinant factor IX (rFIX). A 1-year-old boy with severe hemophilia B was administered prophylactic therapy with rFIX after intracranial bleeding. We found the enlargement of an arachnoid cyst in a follow-up CT scan. He underwent marsupialization of the cyst under the continuous infusion of rFIX. FIX levels were examined in our hospital and the rFIX infusion rate was adjusted in an attempt to keep FIX levels above 90% intraoperatively, and 70% until his 7th post-operative day. We studied the pharmacokinetic profile of rFIX and found a half-time of 25 hours and mean in vivo recovery of 0.69 IU/dl/IU/kg. Reconstituted rFIX also retained at least 95% activity after 72 hours at room temperature. This is the first report of the perioperative management of a child undergoing a neurosurgical procedure under the continuous infusion of rFIX in Japan. Further studies are required before the routine use of this product for continuous infusion.
Migration of an Intracranial Subdural Hematoma to the Spinal Subdural Space: A Case Report.
Kwon, O Ik; Son, Dong Wuk; Kim, Young Ha; Kim, Young Soo; Sung, Soon Ki; Lee, Sang Weon; Song, Geun Sung
A 57-year-old man complained of severe lower back pain and radicular pain in both legs for 1 week after falling from a ladder. Magnetic resonance imaging (MRI) of the spine showed a subdural hematoma (SDH), which was surgically removed. The patient had no back pain or the radicular leg pain at 2 weeks post-surgery. However, he complained of diffuse headaches upon follow-up. Brain computed tomography (CT) and MRI revealed an intracranial SDH, which was immediately removed by surgery. During his 1-year follow-up, he reported that the pain had resolved without recurrence. Simultaneous spinal and intracranial SDH are rare and no standard treatment exists for this condition. This case suggests that it is possible that an intracranial SDH can migrate into the cerebrospinal fluid (CSF) space through an arachnoid tear. CSF circulation allows the intracranial SDH to enter subarachnoid spaces encasing the spinal cord. In order to prevent irreversible damage, surgical intervention should be considered for case of spinal SDH with progressive neurological deficits.
Migration of an Intracranial Subdural Hematoma to the Spinal Subdural Space: A Case Report
Kwon, O Ik; Kim, Young Ha; Kim, Young Soo; Sung, Soon Ki; Lee, Sang Weon; Song, Geun Sung
A 57-year-old man complained of severe lower back pain and radicular pain in both legs for 1 week after falling from a ladder. Magnetic resonance imaging (MRI) of the spine showed a subdural hematoma (SDH), which was surgically removed. The patient had no back pain or the radicular leg pain at 2 weeks post-surgery. However, he complained of diffuse headaches upon follow-up. Brain computed tomography (CT) and MRI revealed an intracranial SDH, which was immediately removed by surgery. During his 1-year follow-up, he reported that the pain had resolved without recurrence. Simultaneous spinal and intracranial SDH are rare and no standard treatment exists for this condition. This case suggests that it is possible that an intracranial SDH can migrate into the cerebrospinal fluid (CSF) space through an arachnoid tear. CSF circulation allows the intracranial SDH to enter subarachnoid spaces encasing the spinal cord. In order to prevent irreversible damage, surgical intervention should be considered for case of spinal SDH with progressive neurological deficits. PMID:26512286
Phase-resolved reflectance spectroscopy on layered turbid media
NASA Astrophysics Data System (ADS)
Hielscher, Andreas H.; Liu, Hanli; Chance, Britton; Tittel, Frank K.; Jacques, Steven L.
In this study, we investigate the influence of layered tissue structures on the phase-resolved reflectance. As a particular example, we consider the affect of the skin, skull, and meninges on noninvasive blood oxygenation determination of the brain. In this case, it's important to know how accurate one can measure the absorption coefficient of the brain through the enclosing layers of different tissues. Experiments were performed on layered gelatin tissue phantoms and the results compared to diffusion theory. It is shown that when a high absorbing medium is placed on top of a low absorbing medium, the absorption coefficient of the lower layer is accessible. In the inverse case, where a low absorbing medium is placed on top of a high absorbing medium, the absorption coefficient of the underlying medium can only be determined if the differences in the absorption coefficient are small, or the top layer is very thin. Investigations on almost absorption and scattering free layers, like the cerebral fluid filled arachnoid, reveal that the determination of the absorption coefficient is barely affected by these kinds of structures.
Is repair of the protruded meninges sufficient for treatment of meningocele?
Yun-Hai, Song; Nan, Bao; Ping-Ping, Gao; Bo, Yang; Cheng, Chen
The present study aimed to investigate the relationship between meningocele and tethered cord syndrome, diagnosis of meningocele associated with tethered cord syndrome, and when to perform surgery and the best surgical procedure. Sixty-nine children with meningocele who were admitted to Shanghai Children's Medical Center were analyzed. The relationship between meningocele and other lesions causing tethered cord syndrome was studied by combining magnetic resonance imaging (MRI) and intraoperative findings. The MRI results and intraoperative findings showed that 67 children (97%) had associated lesions such as tight filum terminale, fibrous band tethering, spinal cord or cauda equina adhesion, diastematomyelia, arachnoid cyst, and epidermoid cyst. The protruded meninges were repaired, and the intraspinal lesions were treated at the same time. Also, the tethered spinal cord was released. No neurological injuries were observed after surgery. The rate of meningocele associated with tethered cord syndrome is very high. MRI is necessary for the diagnosis of meningocele. Active surgical treatment is recommended immediately after definite diagnosis. During surgery, the surgeon should not only repair the protruded meninges but also explore the spinal canal and release the tethered cord.
An enlarged parietal foramen in the late archaic Xujiayao 11 neurocranium from Northern China, and rare anomalies among Pleistocene Homo.
Wu, Xiu-Jie; Xing, Song; Trinkaus, Erik
We report here a neurocranial abnormality previously undescribed in Pleistocene human fossils, an enlarged parietal foramen (EPF) in the early Late Pleistocene Xujiayao 11 parietal bones from the Xujiayao (Houjiayao) site, northern China. Xujiayao 11 is a pair of partial posteromedial parietal bones from an adult. It exhibits thick cranial vault bones, arachnoid granulations, a deviated posterior sagittal suture, and a unilateral (right) parietal lacuna with a posteriorly-directed and enlarged endocranial vascular sulcus. Differential diagnosis indicates that the perforation is a congenital defect, an enlarged parietal foramen, commonly associated with cerebral venous and cranial vault anomalies. It was not lethal given the individual's age-at-death, but it may have been associated with secondary neurological deficiencies. The fossil constitutes the oldest evidence in human evolution of this very rare condition (a single enlarged parietal foramen). In combination with developmental and degenerative abnormalities in other Pleistocene human remains, it suggests demographic and survival patterns among Pleistocene Homo that led to an elevated frequency of conditions unknown or rare among recent humans.
Long-term survival of an infant with diffuse brainstem lesion diagnosed by prenatal MRI: a case report and review of the literature.
Suo-Palosaari, M; Rantala, H; Lehtinen, S; Kumpulainen, T; Salokorpi, N
We describe a unique case of expansive diffuse brainstem lesion diagnosed prenatally by magnetic resonance imaging (MRI) with long-term survival. Findings of fetal and postpartum MRI were highly consistent with the characteristics of diffuse brainstem glioma. Diagnosis was based on the features of MRI, and histopathology was not confirmed by biopsy. Although the prognosis of diffuse brainstem tumor is usually poor, this child was asymptomatic at birth and the neurological condition is still normal at 4 years of age without any treatment. During routine imaging follow-up, diameters of the expansion have remained stable, while the size of the lesion compared to the posterior fossa size has diminished. In addition to brainstem tumor, a skin lesion of the back was observed and MRI of the thoracic spine showed a large asymptomatic extradural cystic lesion suggesting an arachnoid cyst. The pontine tumor of this infant, in agreement with a few previously reported cases, suggests a subgroup of beneficial outcome of expansive diffuse brainstem lesions, particularly in the neonatal period. In this article, we discuss the prognosis and characteristics of pediatric brainstem tumors and differential diagnosis of neonatal brainstem lesions.
Spaceflight-Induced Intracranial Hypertension: An Overview
NASA Technical Reports Server (NTRS)
Traver, William J.
This slide presentation is an overview of the some of the known results of spaceflight induced intracranial hypertension. Historical information from Gemini 5, Apollo, and the space shuttle programs indicated that some vision impairment was reported and a comparison between these historical missions and present missions is included. Optic Disc Edema, Globe Flattening, Choroidal Folds, Hyperopic Shifts and Raised Intracranial Pressure has occurred in Astronauts During and After Long Duration Space Flight. Views illustrate the occurrence of Optic Disc Edema, Globe Flattening, and Choroidal Folds. There are views of the Arachnoid Granulations and Venous return, and the question of spinal or venous compliance issues is discussed. The question of increased blood flow and its relation to increased Cerebrospinal fluid (CSF) is raised. Most observed on-orbit papilledema does not progress, and this might be a function of plateau homeostasis for the higher level of intracranial pressure. There are seven cases of astronauts experiencing in flight and post flight symptoms, which are summarized and follow-up is reviewed along with a comparison of the treatment options. The question is "is there other involvement besides vision," and other Clinical implications are raised,
Clinical and laboratory analysis of late-onset glutaric aciduria type I (GA-I) in Uighur: A report of two cases.
Zhang, Xiaoying; Luo, Qiong
The aim of the present study was to investigate the clinical, biochemical and genetic mutation characteristics of two cases of late-onset glutaric aciduria type I (GA-I) in Uighur. The clinical data and glutaryl-CoA dehydrogenase (GCDH) genetic test results of two cases of late-onset GA-I in Uighur were collected and analyzed, and reviewed with relevant literature. One patient with late-onset GA-I primarily exhibited clinical intermittent headache, while the other patient was asymptomatic. The urinary organic acid analysis detected a large number of glutaric acid and 3-hydroxy glutaric acid, 3-hydroxy-propionic acid. One patient exhibited white matter degeneration in cranial magnetic resonance imaging (MRI) and the other patient showed no abnormality. The two patients both exhibited c. 1204C >T, p.R402W, heterozygous mutation, and c. 532G >A, p.G178R, heterozygous mutation. Besides central nervous system infectious diseases, patients with clinical headache, cranial MRI-suggested bilateral temporal lobe arachnoid cyst and abnormal signals in the basal ganglia should be highly suspected as late-onset GA-I. Early diagnosis and correct treatment are key to improve its prognosis.
Clinical and laboratory analysis of late-onset glutaric aciduria type I (GA-I) in Uighur: A report of two cases
Zhang, Xiaoying; Luo, Qiong
The aim of the present study was to investigate the clinical, biochemical and genetic mutation characteristics of two cases of late-onset glutaric aciduria type I (GA-I) in Uighur. The clinical data and glutaryl-CoA dehydrogenase (GCDH) genetic test results of two cases of late-onset GA-I in Uighur were collected and analyzed, and reviewed with relevant literature. One patient with late-onset GA-I primarily exhibited clinical intermittent headache, while the other patient was asymptomatic. The urinary organic acid analysis detected a large number of glutaric acid and 3-hydroxy glutaric acid, 3-hydroxy-propionic acid. One patient exhibited white matter degeneration in cranial magnetic resonance imaging (MRI) and the other patient showed no abnormality. The two patients both exhibited c. 1204C >T, p.R402W, heterozygous mutation, and c. 532G >A, p.G178R, heterozygous mutation. Besides central nervous system infectious diseases, patients with clinical headache, cranial MRI-suggested bilateral temporal lobe arachnoid cyst and abnormal signals in the basal ganglia should be highly suspected as late-onset GA-I. Early diagnosis and correct treatment are key to improve its prognosis. PMID:28352331
da Vinci robot-assisted keyhole neurosurgery: a cadaver study on feasibility and safety.
Marcus, Hani J; Hughes-Hallett, Archie; Cundy, Thomas P; Yang, Guang-Zhong; Darzi, Ara; Nandi, Dipankar
The goal of this cadaver study was to evaluate the feasibility and safety of da Vinci robot-assisted keyhole neurosurgery. Several keyhole craniotomies were fashioned including supraorbital subfrontal, retrosigmoid and supracerebellar infratentorial. In each case, a simple durotomy was performed, and the flap was retracted. The da Vinci surgical system was then used to perform arachnoid dissection towards the deep-seated intracranial cisterns. It was not possible to simultaneously pass the 12-mm endoscope and instruments through the keyhole craniotomy in any of the approaches performed, limiting visualization. The articulated instruments provided greater dexterity than existing tools, but the instrument arms could not be placed in parallel through the keyhole craniotomy and, therefore, could not be advanced to the deep cisterns without significant clashing. The da Vinci console offered considerable ergonomic advantages over the existing operating room arrangement, allowing the operating surgeon to remain non-sterile and seated comfortably throughout the procedure. However, the lack of haptic feedback was a notable limitation. In conclusion, while robotic platforms have the potential to greatly enhance the performance of transcranial approaches, there is strong justification for research into next-generation robots, better suited to keyhole neurosurgery.
Imaging of cerebellopontine angle lesions: an update. Part 2: intra-axial lesions, skull base lesions that may invade the CPA region, and non-enhancing extra-axial lesions.
Bonneville, Fabrice; Savatovsky, Julien; Chiras, Jacques
Computed tomography (CT) and magnetic resonance (MR) imaging reliably demonstrate typical features of vestibular schwannomas or meningiomas in the vast majority of mass lesions responsible for cerebellopontine angle (CPA) syndrome. However, a large variety of unusual lesions can also be encountered in the CPA. Covering the entire spectrum of lesions potentially found in the CPA, these articles explain the pertinent neuroimaging features that radiologists need to know to make clinically relevant diagnoses in these cases, including data from diffusion- and perfusion-weighted imaging or MR spectroscopy, when available. A diagnostic algorithm based on the lesion's site of origin, shape and margins, density, signal intensity and contrast material uptake is also proposed. Non-enhancing extra-axial CPA masses are cystic (epidermoid cyst, arachnoid cyst, neurenteric cyst) or contain fat (dermoid cyst, lipoma). Tumours can also extend into the CPA by extension from the skull base (paraganglioma, chondromatous tumours, chordoma, cholesterol granuloma, endolymphatic sac tumour). Finally, brain stem or ventricular tumours can present with a significant exophytic component in the CPA that may be difficult to differentiate from an extra-axial lesion (lymphoma, hemangioblastoma, choroid plexus papilloma, ependymoma, glioma, medulloblastoma, dysembryoplastic neuroepithelial tumour).
Forces exerted during microneurosurgery: a cadaver study
Marcus, Hani J; Zareinia, Kourosh; Gan, Liu Shi; Yang, Fang Wei; Lama, Sanju; Yang, Guang-Zhong; Sutherland, Garnette R
Background A prerequisite for the successful design and use of robots in neurosurgery is knowledge of the forces exerted by surgeons during neurosurgical procedures. The aim of the present cadaver study was to measure the surgical instrument forces exerted during microneurosurgery. Methods An experimental apparatus was set up consisting of a platform for human cadaver brains, a Leica microscope to provide illumination and magnification, and a Quanser 6 Degrees-Of-Freedom Telepresence System for tissue manipulation and force measurements. Results The measured forces varied significantly depending on the region of the brain (P = 0.016) and the maneuver performed (P < 0.0001). Moreover, blunt arachnoid dissection was associated with greater force exertion than sharp dissection (0.22 N vs. 0.03 N; P = 0.001). Conclusions The forces necessary to manipulate brain tissue were surprisingly low and varied depending on the anatomical structure being manipulated, and the maneuver performed. Knowledge of such forces could well increase the safety of microsurgery. © 2014 The Authors. The International Journal of Medical Robotics and Computer Assisted Surgery published by John Wiley & Sons, Ltd. PMID:24431265
Acquired Chiari I Malformation with Syringomyelia Secondary to Colloid Cyst with Hydrocephalus-Case Report and Review of Literature.
Thotakura, Amit Kumar; Marabathina, Nageswara R
Acquired Chiari malformation and associated syringomyelia have been previously described following lumbar puncture/drainage, lumboperitoneal shunts, and spontaneous cerebrospinal fluid leakage. In addition to these etiologies, space-occupying lesions such as meningiomas, epidermoid cysts, medulloblastomas, and arachnoid cysts are rare causes of acquired Chiari malformation and syringomyelia. We report a rare case of colloid cyst with hydrocephalus causing secondary Chiari malformation with syringomyelia. A 58-year-old lady presented with neck pain and difficulty in walking and numbness of all 4 limbs of 1-year duration. Diagnostics with magnetic resonance imaging of the head and the cervical spine were done in the referring hospital. The patients was then referred with the diagnosis of colloid cyst with hydrocephalus and Chiari malformation 1 with cervicodorsal syringomyelia. She underwent colloid cyst excision through the transcallosal approach. Postoperatively the patient showed improvement in her symptomatology. Magnetic resonance imaging of the brain and cervical spine at 6 months' follow-up showed resolved Chiari malformation and resolving syrinx. Colloid cyst with hydrocephalus is a rare cause of secondary Chiari malformation with syringomyelia. Surgical management of the underlying lesion improves acquired Chiari malformation and associated syringomyelia. Copyright © 2017 Elsevier Inc. All rights reserved.
Stereotactic CO2 laser therapy for hydrocephalus
NASA Astrophysics Data System (ADS)
Kozodoy-Pins, Rebecca L.; Harrington, James A.; Zazanis, George A.; Nosko, Michael G.; Lehman, Richard M.
A new fiber-optic delivery system for CO2 radiation has been used to successfully treat non-communicating hydrocephalus. This system consists of a hollow sapphire waveguide employed in the lumen of a stereotactically-guided neuroendoscope. CO2 gas flows through the bore of the hollow waveguide, creating a path for the laser beam through the cerebrospinal fluid (CSF). This delivery system has the advantages of both visualization and guided CO2 laser radiation without the same 4.3 mm diameter scope. Several patients with hydrocephalus were treated with this new system. The laser was used to create a passage in the floor of the ventricle to allow the flow of CSF from the ventricles to the sub-arachnoid space. Initial postoperative results demonstrated a relief of the clinical symptoms. Long-term results will indicate if this type of therapy will be superior to the use of implanted silicone shunts. Since CO2 laser radiation at 10.6 micrometers is strongly absorbed by the water in tissue and CSF, damage to tissue surrounding the lesion with each laser pulse is limited. The accuracy and safety of this technique may prove it to be an advantageous therapy for obstructive hydrocephalus.
Synteny of human chromosomes 14 and 15 in the platyrrhines (Primates, Platyrrhini)
In order to study the intra- and interspecific variability of the 14/15 association in Platyrrhini, we analyzed 15 species from 13 genera, including species that had not been described yet. The DNA libraries of human chromosomes 14 and 15 were hybridized to metaphases of Alouatta guariba clamitans, A. caraya, A. sara, Ateles paniscus chamek, Lagothrix lagothricha, Brachyteles arachnoides, Saguinus midas midas, Leontopithecus chrysomelas, Callimico goeldii, Callithrix sp., Cebus apella, Aotus nigriceps, Cacajao melanocephalus,Chiropotes satanas and Callicebus caligatus. The 14/15 hybridization pattern was present in 13 species, but not in Alouatta sara that showed a 14/15/14 pattern and Aotus nigriceps that showed a 15/14/15/14 pattern. In the majority of the species, the HSA 14 homologue retained synteny for the entire chromosome, whereas the HSA 15 homologue displayed fragmented segments. Within primates, the New World monkeys represent the taxon with the highest variability in chromosome number (2n = 16 to 62). The presence of the HSA 14/15 association in all species and subspecies studied herein confirms that this association is the ancestral condition for platyrrhines and that this association has been retained in most platyrrhines, despite the occurrence of extensive inter- and intrachromosomal rearrangements in this infraorder of Primates. PMID:21637455
Post spinal puncture headache, an old problem and new concepts: review of articles about predisposing factors
Jabbari, Ali; Alijanpour, Ebrahim; Mir, Mehrafza; Bani hashem, Nadia; Rabiea, Seyed Mozaffar; Rupani, Mohammad Ali
Post spinal puncture headache (PSPH) is a well known complication of spinal anesthesia. It occurs after spinal anesthesia induction due to dural and arachnoid puncture and has a significant effect on the patient’s postoperative well being. This manuscript is based on an observational study that runs on Babol University of Medical Sciences and review of literatures about current concepts about the incidence, risk factors and predisposing factors of post spinal puncture headache. The overall incidence of post-dural puncture headache after intentional dural puncture varies form 0.1-36%, while it is about 3.1% by atraumatic spinal needle 25G Whitacre. 25G Quincke needle with a medium bevel cutting is popular with widespread use and the incidence of PSPH is about 25%, but its incidence obtained 17.3% by spinal needle 25G Quincke in our observation. The association of predisposing factors like female, young age, pregnancy, low body mass index, multiple dural puncture, inexpert operators and past medical history of chronic headache, expose the patient to PSPH. The identification of factors that predict the likelihood of PSPH is important so that measures can be taken to minimize this painful complication resulting from spinal anesthesia. PMID:24009943
[A case of cavernous angioma at the convexity in the dura mater: characteristics of images in the literature].
Yonezawa, Ushio; Ikawa, Fusao; Hamasaki, Osamu; Hidaka, Toshikazu; Kurokawa, Yasuharu; Onuma, Hideyuki
We describe a rare case of cavernous angioma in the dura mater and discuss published MRI findings on similar cases. The patient was a 78-year-old woman who was referred to Shimane Prefectural Central Hospital with complaints of headaches. We were subsequently able to identify a tumor at the convexity in the dura mater. The tumor showed a high intensity on T2-weighted images and was heterogeneously enhanced on contrast-enhanced T1-weighted images. The maximum size of the tumor was 35 mm. Moreover, preoperative angiography showed a slight vascularity in the tumor. We performed surgery with the expectation of finding a meningioma, metastatic brain tumor, or another mesenchymal tumor. The tumor was dark and red, attached to the dura mater, and adhered to the arachnoid. However, we were able to peel the tumor away from the meninges and achieved a total removal of the mass, successfully cutting a fine feeding cortical artery. The patient was discharged without neurological defects 9 days after surgery;the pathological diagnosis was cavernous angioma. In conclusion, it is difficult to discern between meningioma and cavernous angioma in the dura mater. However, the specificity of high intensity on T2-weighted images is relatively high, and preoperative diagnosis can be determined by MRI and angiography findings.
Surgical treatment of parapontine epidermoid cysts presenting with trigeminal neuralgia.
Guo, Zhilin; Ouyang, Huoniu; Cheng, Zhihua
We retrospectively reviewed the management of 49 patients with parapontine epidermoid cyst presenting with trigeminal neuralgia, emphasizing the importance of fully removing the tumor to relieve the trigeminal neuralgia. Clinical symptoms, MRI, the operative approach, and post-operative results were examined. Trigeminal neuralgia was noted in all patients. The mean duration from onset of symptoms to surgery was 18 months. Total removal was achieved in 23 patients, near-total removal in 21, and subtotal removal in five patients. However, all tumor capsule that adhered to the trigeminal nerve was completely removed. After the operation, 33 patients developed facial hypoesthesia, three complained of double vision, and two developed acute hydrocephalus. At six months of follow-up, all patients had recovered and returned to their normal lives. At 2 years of follow-up, one patient experienced pain recurrence and underwent another operation. Parapontine epidermoid cysts either encase cranial nerve (CN) V but with intact arachnoid between the capsule and the nerve, or compress and distort the nerve with tumor capsule adherent or attached to the nerve surface. Resecting the tumor capsule's attachment to CN V is critical in relieving pain, even though this method may damage the nerve. Copyright © 2010 Elsevier Ltd. All rights reserved.
Demographic monitoring of wild muriqui populations: Criteria for defining priority areas and monitoring intensity.
Strier, Karen B; Possamai, Carla B; Tabacow, Fernanda P; Pissinatti, Alcides; Lanna, Andre M; Rodrigues de Melo, Fabiano; Moreira, Leandro; Talebi, Maurício; Breves, Paula; Mendes, Sérgio L; Jerusalinsky, Leandro
Demographic data are essential to assessments of the status of endangered species. However, establishing an integrated monitoring program to obtain useful data on contemporary and future population trends requires both the identification of priority areas and populations and realistic evaluations of the kinds of data that can be obtained under different monitoring regimes. We analyzed all known populations of a critically endangered primate, the muriqui (genus: Brachyteles) using population size, genetic uniqueness, geographic importance (including potential importance in corridor programs) and implementability scores to define monitoring priorities. Our analyses revealed nine priority populations for the northern muriqui (B. hypoxanthus) and nine for the southern muriqui (B. arachnoides). In addition, we employed knowledge of muriqui developmental and life history characteristics to define the minimum monitoring intensity needed to evaluate demographic trends along a continuum ranging from simple descriptive changes in population size to predictions of population changes derived from individual based life histories. Our study, stimulated by the Brazilian government's National Action Plan for the Conservation of Muriquis, is fundamental to meeting the conservation goals for this genus, and also provides a model for defining priorities and methods for the implementation of integrated demographic monitoring programs for other endangered and critically endangered species of primates.
Synteny of human chromosomes 14 and 15 in the platyrrhines (Primates, Platyrrhini).
Gifalli-Iughetti, Cristiani; Koiffmann, Célia P
In order to study the intra- and interspecific variability of the 14/15 association in Platyrrhini, we analyzed 15 species from 13 genera, including species that had not been described yet. The DNA libraries of human chromosomes 14 and 15 were hybridized to metaphases of Alouatta guariba clamitans, A. caraya, A. sara, Ateles paniscus chamek, Lagothrix lagothricha, Brachyteles arachnoides, Saguinus midas midas, Leontopithecus chrysomelas, Callimico goeldii, Callithrix sp., Cebus apella, Aotus nigriceps, Cacajao melanocephalus,Chiropotes satanas and Callicebus caligatus. The 14/15 hybridization pattern was present in 13 species, but not in Alouatta sara that showed a 14/15/14 pattern and Aotus nigriceps that showed a 15/14/15/14 pattern. In the majority of the species, the HSA 14 homologue retained synteny for the entire chromosome, whereas the HSA 15 homologue displayed fragmented segments. Within primates, the New World monkeys represent the taxon with the highest variability in chromosome number (2n = 16 to 62). The presence of the HSA 14/15 association in all species and subspecies studied herein confirms that this association is the ancestral condition for platyrrhines and that this association has been retained in most platyrrhines, despite the occurrence of extensive inter- and intrachromosomal rearrangements in this infraorder of Primates.
Non-traumatic subdural hematoma secondary to septic brain embolism: A rare cause of unexpected death in a drug addict suffering from undiagnosed bacterial endocarditis.
Geisenberger, D; Huppertz, L M; Büchsel, M; Kramer, L; Pollak, S; Große Perdekamp, M
Acute subdural hematomas are mostly due to blunt traumatization of the head. In rare instances, subdural bleeding occurs without evidence of a previous trauma following spontaneous hemorrhage, e.g. from a ruptured aneurysm or an intracerebral hematoma perforating the brain surface and the arachnoid. The paper presents the morphological, microbiological and toxicological findings in a 38-year-old drug addict who was found by his partner in a dazed state. When brought to a hospital, he underwent trepanation to empty a right-sided subdural hematoma, but he died already 4h after admission. Autopsy revealed previously undiagnosed infective endocarditis of the aortic valve as well as multiple infarctions of brain, spleen and kidneys obviously caused by septic emboli. The subdural hematoma originated from a subcortical brain hemorrhage which had perforated into the subdural space. Microbiological investigation of the polypous vegetations adhering to the aortic valve revealed colonization by Streptococcus mitis and Klebsiella oxytoca. According to the toxicological analysis, no psychotropic substances had contributed to the lethal outcome. The case reported underlines that all deaths of drug addicts should be subjected to complete forensic autopsy, as apart from intoxications also natural and traumatic causes of death have to be taken into consideration. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Bengt Liliequist: life and accomplishments of a true renaissance man.
Connor, David E; Nanda, Anil
In the 1970s, the membrane of Liliequist became the accepted name for a small band of arachnoid membrane separating the interpeduncular and chiasmatic cisterns, making it one of the most recent of the universally accepted medical eponyms. The story of its discovery, however, cannot be told without a thorough understanding of the man responsible and his contribution to the growth of a specialty. Bengt Liliequist lived during what many would consider the Golden Age of neuroradiology. With his colleagues at the Serafimer Hospital in Stockholm, he helped set the standard for appropriate imaging of the CNS and contributed to more accurate localization of intracerebral as well as spinal lesions. The pneumoencephalographic discovery of the membrane that was to bear his name serves merely as a starting point for a career that spanned five decades and included the defense of two separate doctoral theses, the last of which occurred after his 80th birthday. Although the recognition of neuroradiology as a subspecialty did not occur in his home country of Sweden until after his retirement, and technological progress saw the obsolescence of the procedure that he had mastered, Dr. Liliequist's accomplishments and his contributions to the current understanding of neuroanatomy merit our continued praise.
Volcanism and Volatile Recycling on Venus from Lithospheric Delamination
NASA Technical Reports Server (NTRS)
Elkins-Tanton, L. T.; Hess, P. C.; Smrekar, S. E.; Parmentier, E. M.
Venus has an unmoving lithosphere, a young surface indicative of volcanic resurfacing, and a wide variety of volcanic and tectonic features. The planet s ubiquitous magmatic features include 100,000 small shield volcanoes as well as the descriptively named pancakes, ticks, and arachnoids . Coronae, volcanic and tectonic features up to 2,600 km in diameter, have been attributed to lithospheric interactions with upwelling plumes [e.g., 2], but more recently to delamination of the lower lithosphere with  or without  a central upwelling. Lavas issuing from different volcanic features appear to have a range of compositions, as evidenced by their apparent viscosities and by data from Soviet landers. Steep-sided or "pancake" domes [e.g., 5] appear to consist of more viscous magma , perhaps silicic compositions created by remelting basaltic crust . These steep-sided domes are associated with coronae and with shield volcanoes effusing basaltic magmas [7,8] with apparently low viscosities (low enough to allow fluid flow for hundreds of km, creating channels reminiscent of water rivers on Earth). Pancake domes, in contrast, can be up to 3 km in height and have volumes from 30 to approx.3,000 km3 [calculated from data in 8], and hundreds dot the planet [6-8].
The effects of intrathecal administration of betamethasone over the dogs' spinal cord and meninges.
Barros, Guilherme Antonio Moreira de; Marques, Mariângela Esther Alencar; Ganem, Eliana Marisa
To determinate the potential clinical and histological changes due the injection of betamethasone, when administered into the canine intrathecal space. Twenty one animals were included in a random and blind manner in the study. After general anesthesia, intrathecal puncture was performed and 1 ml of the random solution was injected. The G1 dogs received 0.9% saline solution, the G2 dogs received 1.75 mg betamethasone and the G3 dogs received 3.5 mg of betamethasone. The animals were clinically evaluated for 21 days and then sacrificed. The lumbar and sacral portions of the spinal cord were removed for light microscopy histological analyses. No clinical changes were observed in any of the animals included in this study. No histological changes were observed in G1 animals. Inflammatory infiltration was observed in two dogs, one in G2, another in G3. Hemorrhage and necrosis were also seen in the G2 dog which inflammatory infiltration was detected. In other two dogs, one from G2 and another from G3, there was discreet fibrosis and thickness of the arachnoid layer which was focal in one and diffuse in the other. Intrathecal administration of betamethasone caused histological changes in the spinal cord and meninges in some of the dogs involved in this study.
The Relationship of Three-Dimensional Human Skull Motion to Brain Tissue Deformation in Magnetic Resonance Elastography Studies
Badachhape, Andrew A.; Okamoto, Ruth J.; Durham, Ramona S.; Efron, Brent D.; Nadell, Sam J.; Johnson, Curtis L.; Bayly, Philip V.
In traumatic brain injury (TBI), membranes such as the dura mater, arachnoid mater, and pia mater play a vital role in transmitting motion from the skull to brain tissue. Magnetic resonance elastography (MRE) is an imaging technique developed for noninvasive estimation of soft tissue material parameters. In MRE, dynamic deformation of brain tissue is induced by skull vibrations during magnetic resonance imaging (MRI); however, skull motion and its mode of transmission to the brain remain largely uncharacterized. In this study, displacements of points in the skull, reconstructed using data from an array of MRI-safe accelerometers, were compared to displacements of neighboring material points in brain tissue, estimated from MRE measurements. Comparison of the relative amplitudes, directions, and temporal phases of harmonic motion in the skulls and brains of six human subjects shows that the skull–brain interface significantly attenuates and delays transmission of motion from skull to brain. In contrast, in a cylindrical gelatin “phantom,” displacements of the rigid case (reconstructed from accelerometer data) were transmitted to the gelatin inside (estimated from MRE data) with little attenuation or phase lag. This quantitative characterization of the skull–brain interface will be valuable in the parameterization and validation of computer models of TBI. PMID:28267188
The Relationship of Three-Dimensional Human Skull Motion to Brain Tissue Deformation in Magnetic Resonance Elastography Studies.
Badachhape, Andrew A; Okamoto, Ruth J; Durham, Ramona S; Efron, Brent D; Nadell, Sam J; Johnson, Curtis L; Bayly, Philip V
In traumatic brain injury (TBI), membranes such as the dura mater, arachnoid mater, and pia mater play a vital role in transmitting motion from the skull to brain tissue. Magnetic resonance elastography (MRE) is an imaging technique developed for noninvasive estimation of soft tissue material parameters. In MRE, dynamic deformation of brain tissue is induced by skull vibrations during magnetic resonance imaging (MRI); however, skull motion and its mode of transmission to the brain remain largely uncharacterized. In this study, displacements of points in the skull, reconstructed using data from an array of MRI-safe accelerometers, were compared to displacements of neighboring material points in brain tissue, estimated from MRE measurements. Comparison of the relative amplitudes, directions, and temporal phases of harmonic motion in the skulls and brains of six human subjects shows that the skull-brain interface significantly attenuates and delays transmission of motion from skull to brain. In contrast, in a cylindrical gelatin "phantom," displacements of the rigid case (reconstructed from accelerometer data) were transmitted to the gelatin inside (estimated from MRE data) with little attenuation or phase lag. This quantitative characterization of the skull-brain interface will be valuable in the parameterization and validation of computer models of TBI.
Exposure of wide cerebellomedullary cisterns for vascular lesion surgeries in cerebellomedullary cisterns: opening of unilateral cerebellomedullary fissures combined with lateral foramen magnum approach.
Matsushima, Toshio; Kawashima, Masatou; Inoue, Kohei; Matsushima, Ken; Miki, Koichi
To clarify microsurgical anatomic features of the cerebellomedullary fissure (CMF), the natural cleavage plane between the cerebellum and the medulla, and its relationship to the cerebellomedullary cistern (CMC) and to describe a surgical technique that uses the unilateral trans-CMF approach for CMC surgeries. In the anatomic study, 2 formalin-fixed cadaver heads were used. In the clinical study, 3 patients with vertebral artery-posterior inferior cerebellar artery aneurysms and 3 patients with glossopharyngeal neuralgia were surgically treated through the unilateral trans-CMF approach combined with the transcondylar fossa approach, which is a lateral foramen magnum approach. The CMC was present at the lateral end of the CMF. The CMF was closed by arachnoidal adhesion, and the cerebellar hemisphere was superiorly attached to the cerebellar peduncle. After the unilateral CMF was completely opened, the cerebellar hemisphere was easily retracted rostrodorsally. Clinically, almost completely opening the unilateral CMF markedly enabled the retraction of the biventral lobule to obtain a wide surgical field safely for vascular CMC lesions. We present 2 representative cases. Combined unilateral trans-CMF/lateral foramen magnum approaches provide a wide and close surgical field in the CMC, allowing easy and safe CMC surgery. Copyright © 2014 Elsevier Inc. All rights reserved.
A new look at cerebrospinal fluid circulation
According to the traditional understanding of cerebrospinal fluid (CSF) physiology, the majority of CSF is produced by the choroid plexus, circulates through the ventricles, the cisterns, and the subarachnoid space to be absorbed into the blood by the arachnoid villi. This review surveys key developments leading to the traditional concept. Challenging this concept are novel insights utilizing molecular and cellular biology as well as neuroimaging, which indicate that CSF physiology may be much more complex than previously believed. The CSF circulation comprises not only a directed flow of CSF, but in addition a pulsatile to and fro movement throughout the entire brain with local fluid exchange between blood, interstitial fluid, and CSF. Astrocytes, aquaporins, and other membrane transporters are key elements in brain water and CSF homeostasis. A continuous bidirectional fluid exchange at the blood brain barrier produces flow rates, which exceed the choroidal CSF production rate by far. The CSF circulation around blood vessels penetrating from the subarachnoid space into the Virchow Robin spaces provides both a drainage pathway for the clearance of waste molecules from the brain and a site for the interaction of the systemic immune system with that of the brain. Important physiological functions, for example the regeneration of the brain during sleep, may depend on CSF circulation. PMID:24817998
["Normal pressure" hydrocephalus].
Normal pressure hydrocephalus (NPH) or, more precisely, chronic adult hydrocephalus, is a complex condition. Even if the basic mechanism is found in an impediment to CSF absorption, the underlying pathology is heterogeneous. In secondary NPH, the disruption of normal CSF pathways, following meningitis or sub-arachnoid haemorrhage, is responsible for ventricular dilatation. However, in about half of the cases, the etiology remains obscure. NPH is more frequently found in elderly people, probably in relation with the increased incidence of cerebrovascular disease. The diagnosis of NPH is based upon a triad of clinical symptoms. The main symptom is gait disturbances, followed by urinary incontinence and various degree of cognitive changes. The latter two symptoms are not prerequisites for the diagnosis. Radiological ventricular dilatation without cortical sulcal enlargement is a key factor, as well as substantial clinical improvement after CSF withdrawal (CSF tap test). Other CSF dynamic studies and various imaging investigations have been proposed to improve diagnostic accuracy, but no simple test can predict the results of CSF drainage. The current treatment is ventriculo-peritonial shunting, ideally using an adjustable valve. Results are directly dependent upon the accuracy of the preoperative diagnosis. Post-surgical complications may be observed in about 10% of cases.
The effects of beta-endorphin: state change modification.
Veening, Jan G; Barendregt, Henk P
Beta-endorphin (β-END) is an opioid neuropeptide which has an important role in the development of hypotheses concerning the non-synaptic or paracrine communication of brain messages. This kind of communication between neurons has been designated volume transmission (VT) to differentiate it clearly from synaptic communication. VT occurs over short as well as long distances via the extracellular space in the brain, as well as via the cerebrospinal fluid (CSF) flowing through the ventricular spaces inside the brain and the arachnoid space surrounding the central nervous system (CNS). To understand how β-END can have specific behavioral effects, we use the notion behavioral state, inspired by the concept of machine state, coming from Turing (Proc London Math Soc, Series 2,42:230-265, 1937). In section 1.4 the sequential organization of male rat behavior is explained showing that an animal is not free to switch into another state at any given moment. Funneling-constraints restrict the number of possible behavioral transitions in specific phases while at other moments in the sequence the transition to other behavioral states is almost completely open. The effects of β-END on behaviors like food intake and sexual behavior, and the mechanisms involved in reward, meditation and pain control are discussed in detail. The effects on the sequential organization of behavior and on state transitions dominate the description of these effects.
Cytoarchitectonic study of the trigeminal ganglion in humans.
Krastev, Dimo Stoyanov; Apostolov, Alexander
The trigeminal ganglion (TG), a cluster of pseudounipolar neurons, is located in the trigeminal impression of the temporal pyramid. It is covered by a sheath of the dura mater and arachnoid and is near the rear end of the cavernous sinus. The peripheral processes of the pseudounipolar cells are involved in the formation of the first and second branch and the sensory part of the third branch of the fifth cranial nerve, and the central ones form the sensory root of the nerve, which penetrates at the level of the middle cerebellar peduncle, aside from the pons, and terminate in the sensory nuclei of the trigeminal complex. We found that the primary sensory neurons involved in sensory innervation of the orofacial complex are a diverse group. Although they possess the general structure of pseudounipolar neurons, there are significant differences among them, seen in varying intensities of staining. Based on our investigations we classified the neurons into 7 groups, i.e. large, subdivided into light and dark, medium, also light and dark, and small light and dark, and, moreover, neurons with an irregular shape of their perikarya. Further research by applying various immunohistochemical methods will clarify whether differences in the morphological patterns of the neurons are associated with differences in the neurochemical composition of various neuronal types.
Cytoarchitectonic study of the trigeminal ganglion in humans
KRASTEV, DIMO STOYANOV; APOSTOLOV, ALEXANDER
The trigeminal ganglion (TG), a cluster of pseudounipolar neurons, is located in the trigeminal impression of the temporal pyramid. It is covered by a sheath of the dura mater and arachnoid and is near the rear end of the cavernous sinus. The peripheral processes of the pseudounipolar cells are involved in the formation of the first and second branch and the sensory part of the third branch of the fifth cranial nerve, and the central ones form the sensory root of the nerve, which penetrates at the level of the middle cerebellar peduncle, aside from the pons, and terminate in the sensory nuclei of the trigeminal complex. We found that the primary sensory neurons involved in sensory innervation of the orofacial complex are a diverse group. Although they possess the general structure of pseudounipolar neurons, there are significant differences among them, seen in varying intensities of staining. Based on our investigations we classified the neurons into 7 groups, i.e. large, subdivided into light and dark, medium, also light and dark, and small light and dark, and, moreover, neurons with an irregular shape of their perikarya. Further research by applying various immunohistochemical methods will clarify whether differences in the morphological patterns of the neurons are associated with differences in the neurochemical composition of various neuronal types. PMID:26527926
Chronic active Epstein-Barr virus infection in an adult with no detectable immune deficiency.
de Boer, M; Mol, M J T M; Bogman, M J J T; Galama, J M D; Raymakers, R A P
Epstein-Barr virus (EBV) establishes lifelong latent infection. In some patients the host-virus balance is disturbed, resulting in a chronic active EBV infection. The following case illustrates the difficulty in diagnosing and treating chronic EBV infection. A 30-year-old woman was referred because of recurrent swellings of lymphatic tissue of both eyelids, orbit and lymph nodes and general malaise since the age of 19. In the past, repeated biopsies showed MALT lymphoma and nonspecific lymphoid infiltrations. Now, a biopsy of an axillary lymph node showed paracortical hyperplasia with a polymorphous polyclonal lymphoid proliferation, and large numbers of EBV-encoded small RNA (EBER) positive cells, consistent with EBV infection. Laboratory investigation showed a high EBV viral load. No evidence of immunodeficiency was found. Chronic active EBV infection (CAEBV) was diagnosed. Treatment with high-dose acyclovir did not significantly reduce the viral load. Rituximab was given in an attempt to reduce the amount of EBV-infected B lymphocytes. However, soon after the second dose the patient died of a sub-arachnoidal haemorrhage. This case report illustrates CAEBV as a rare manifestation of EBV-induced disease, which will be detected more frequently with the use of EBV-EBER hybridisation of lymph nodes and polymerase chain reaction (PCR) for EBV DNA. The prognosis is poor with no established therapeutic strategies.
Spinal extradural cyst: A case report and review of literature.
Lee, Sean Wy; Foo, Aaron; Tan, Char Loo; Tan, Thomas; Lwin, Sein; Yeo, Tseng Tsai; Nga, Vincent Dw
Spinal extradural cyst (SEDC) accounts for less than 1% of spinal epidural lesions. It is commonly asymptomatic but can give rise to back pain and compressive neurological symptoms. We report the case of a 51-year-old male who presented with gait difficulties over five months associated with occasional urge incontinence. Clinical examination revealed signs suggestive of thoracic myelopathy with bilateral lower limbs spasticity, decreased proprioception and pin prick sensation. MRI showed a Thoracic (T) 7-T9 extradural cystic lesion with an area of flow void on the right side between T8 and T9. A right hemilaminotomy was initially performed, dural defect identified and repaired primarily. Unfortunately, there was a recurrence of the SEDC 2 weeks post-operation and a T7-T9 laminoplasty with complete excision was performed. Computer-tomography (CT) myelography or MRI flow study best visualises the communication between the epidural cyst and sub-arachnoid space. The ideal surgical management for SEDC remains controversial. Our case suggests that there may be higher recurrence associated with fenestration of the SEDC and closure of the dural defect, but perhaps higher complications associated with complete excision. We present a case report and literature review of the terminology, presentation, recommended investigations, management and outcomes of patients with SEDC. Copyright © 2018 Elsevier Inc. All rights reserved.
The Global Neurological Burden of Tuberculosis.
Thakur, Kiran; Das, Mitashee; Dooley, Kelly E; Gupta, Amita
Central nervous system (CNS) involvement of tuberculosis (TB) is the most severe manifestation of TB and accounts for approximately 5 to 10% of all extrapulmonary TB (EPTB) cases and approximately 1% of all TB cases. TB meningitis (TBM) is the most common form of CNS TB, though other forms occur, often in conjunction with TBM, including intracranial tuberculomas, tuberculous brain abscesses, and spinal tubercular arachnoiditis. CNS TB often presents with nonspecific clinical features that mimic symptoms of other neurological conditions, often making diagnosis difficult. Defining neuroimaging characteristics of TBM include thick basal meningeal enhancement, hydrocephalus, and parenchymal infarctions most commonly involving the basal ganglia and internal capsule. Traditional cerebrospinal fluid sample analysis frequently requires lengthy times-to-result and have low sensitivity. Given the pitfalls of conventional CNS TB diagnostic methods, various molecular-based methods, including immunoassays and polymerase chain reaction (PCR)-based assays have emerged as alternative diagnostic tools due to their rapidity, sensitivity, and specificity. Expert panels on TBM have recently emphasized the need for standard research procedures with updated case definitions and standardized study methods, which will hopefully pave the way for more robust multicenter international studies. In this article, we review the epidemiology, diagnosis, molecular factors associated with disease presentation and outcome, and treatment of CNS TB. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
A case of disseminated central nervous system sparganosis.
Noiphithak, Raywat; Doungprasert, Gahn
Sparganosis is a very rare parasitic infection in various organs caused by the larvae of tapeworms called spargana. The larva usually lodges in the central nervous system (CNS) and the orbit. However, lumbar spinal canal involvement, as noted in the present case, is extremely rare. We report a rare case of disseminated CNS sparganosis involving the brain and spinal canal and review the literature. A 54-year-old man presented with progressive low back pain and neurological deficit at the lumbosacral level for 2 months. Imaging indicated arachnoiditis and an abnormal lesion at the L4-5 vertebral level. The patient underwent laminectomy of the L4-5 with lesionectomy and lysis of adhesions between the nerve roots. Microscopic examination indicated sparganum infection. Further brain imaging revealed evidence of chronic inflammation in the left parieto-occipital area without evidence of live parasites. In addition, an ophthalmologist reported a nonactive lesion in the right conjunctiva. The patient recovered well after surgery, although he had residual back pain and bladder dysfunction probably due to severe adhesion of the lumbosacral nerve roots. CNS sparganosis can cause various neurological symptoms similar to those of other CNS infections. A preoperative enzyme-linked immunosorbent assay is helpful for diagnosis, especially in endemic areas. Surgical removal of the worm remains the treatment of choice.
Should incidental findings in diagnostic imaging be reported?
Panelli Santos, Karina C; Fujita, Mariko; Oliveira, Jefferson X; Yanagi, Yoshinobu; Asaumi, Junichi
Recent improvements in image quality have contributed to an increasing number of incidental findings (IF). Also called as "incidentalomas", this generic term refers to an entity discovered unexpectedly on an imaging examination performed for other reason. Commonly, normal variants, minor developmental anomalies and imaging artifacts are described as potential pathology. Some IF were reported in magnetic resonance imaging (MRI) exam of temporomandibular joint (TMJ), including IF in the brain, maxillary sinus, ethmoidal cells, mastoid cells, salivary glands, muscles. The aim of this study is to evaluate the prevalence of IF on MRI of TMJ from Japanese patients. An image archive from 872 patients referred to MRI evaluation due to TMJ symptomatology was assessed. Three experienced radiologists evaluated all images, and the final diagnosis was achieved by consensus. The data regarding IF was recorded, considering only tumor and tumor-like lesions. A total of 12 (1.38%) of tumor and tumor-like lesions were observed from all 872 MRI exams evaluated. The most frequent lesion was arachnoid cyst (0.45%), followed by neoplastic lesions (0.22%). The question "should every IF be reported?" is still difficult to answer. Relevant IF are rare, and radiologists are expected to be reasonable: think about the adverse effects of reporting an IF, and, based on their own judgment, choose for a positive or a negative answer.
Cranial dural arteriovenous shunts. Part 1. Anatomy and embryology of the bridging and emissary veins.
Baltsavias, Gerasimos; Parthasarathi, Venkatraman; Aydin, Emre; Al Schameri, Rahman A; Roth, Peter; Valavanis, Anton
We reviewed the anatomy and embryology of the bridging and emissary veins aiming to elucidate aspects related to the cranial dural arteriovenous fistulae. Data from relevant articles on the anatomy and embryology of the bridging and emissary veins were identified using one electronic database, supplemented by data from selected reference texts. Persisting fetal pial-arachnoidal veins correspond to the adult bridging veins. Relevant embryologic descriptions are based on the classic scheme of five divisions of the brain (telencephalon, diencephalon, mesencephalon, metencephalon, myelencephalon). Variation in their exact position and the number of bridging veins is the rule and certain locations, particularly that of the anterior cranial fossa and lower posterior cranial fossa are often neglected in prior descriptions. The distal segment of a bridging vein is part of the dural system and can be primarily involved in cranial dural arteriovenous lesions by constituting the actual site of the shunt. The veins in the lamina cribriformis exhibit a bridging-emissary vein pattern similar to the spinal configuration. The emissary veins connect the dural venous system with the extracranial venous system and are often involved in dural arteriovenous lesions. Cranial dural shunts may develop in three distinct areas of the cranial venous system: the dural sinuses and their interfaces with bridging veins and emissary veins. The exact site of the lesion may dictate the arterial feeders and original venous drainage pattern.
[The blood-brain barrier and drug delivery in the central nervous system].
Loch-Neckel, Gecioni; Koepp, Janice
To provide an updated view of the difficulties due to barriers and strategies used to allow the release of drugs in the central nervous system. The difficulty for the treatment of many diseases of the central nervous system, through the use of intra-venous drugs, is due to the presence of barriers that prevent the release of the same: the blood-brain barrier, blood-cerebro-spinal fluid barrier and the blood-arachnoid barrier. The blood-brain barrier is the main barrier for the transport of drugs in the brain that also acts as a immunologic and metabolic barrier. The endothelial cells of the blood-brain barrier are connected to a junction complex through the interaction of transmembrane proteins that protrude from de inside to the outside, forming a connection between the endothelial cells. The transport of substances to the brain depends on the mechanisms of transport present in the barrier and the diffusion of these compounds also depends on the physicochemical characteristics of the molecule. Some diseases alter the permeability of the blood-brain barrier and thus the passage of drugs. Strategies such as the use of methods for drug delivery in the brain have been investigated. Further details regarding the mechanisms of transport across the blood-brain barrier and the changes in neuropathology would provide important information about the etiology of diseases and lead to better therapeutic strategies.
Risk factors for early post-operative neurological deterioration in dogs undergoing a cervical dorsal laminectomy or hemilaminectomy: 100 cases (2002-2014).
Taylor-Brown, F E; Cardy, T J A; Liebel, F X; Garosi, L; Kenny, P J; Volk, H A; De Decker, S
Early post-operative neurological deterioration is a well-known complication following dorsal cervical laminectomies and hemilaminectomies in dogs. This study aimed to evaluate potential risk factors for early post-operative neurological deterioration following these surgical procedures. Medical records of 100 dogs that had undergone a cervical dorsal laminectomy or hemilaminectomy between 2002 and 2014 were assessed retrospectively. Assessed variables included signalment, bodyweight, duration of clinical signs, neurological status before surgery, diagnosis, surgical site, type and extent of surgery and duration of procedure. Outcome measures were neurological status immediately following surgery and duration of hospitalisation. Univariate statistical analysis was performed to identify variables to be included in a multivariate model. Diagnoses included osseous associated cervical spondylomyelopathy (OACSM; n = 41), acute intervertebral disk extrusion (IVDE; 31), meningioma (11), spinal arachnoid diverticulum (10) and vertebral arch anomalies (7). Overall 54% (95% CI 45.25-64.75) of dogs were neurologically worse 48 h post-operatively. Multivariate statistical analysis identified four factors significantly related to early post-operative neurological outcome. Diagnoses of OACSM or meningioma were considered the strongest variables to predict early post-operative neurological deterioration, followed by higher (more severely affected) neurological grade before surgery and longer surgery time. This information can aid in the management of expectations of clinical staff and owners with dogs undergoing these surgical procedures. Copyright © 2015 Elsevier Ltd. All rights reserved.
Cerebrovascular Smooth Muscle Actin Is Increased in Non-Demented Subjects with Frequent Senile Plaques at Autopsy: Implications for the Pathogenesis of Alzheimer Disease
Hulette, Christine M.; Ervin, John F.; Edmonds, Yvette; Antoine, Samantha; Stewart, Nicolas; Szymanski, Mari H.; Hayden, Kathleen M; Pieper, Carl F.; Burke, James R.; Welsh-Bohmer, Kathleen A.
We previously found that vascular smooth muscle actin (SMA) is reduced in the brains of patients with late stage Alzheimer disease (AD) compared to brains of non-demented, neuropathologically normal subjects. To assess the pathogenetic significance and disease specificity of this finding, we studied 3 additional patient groups: non-demented subjects without significant AD type pathology (“Normal”, n = 20); non-demented subjects with frequent senile plaques at autopsy (“Preclinical AD”, n = 20); and subjects with frontotemporal dementia, (“FTD”, n = 10). The groups were matched for gender and age with those previously reported; SMA immunohistochemistry and image analysis were performed as previously described. Surprisingly, SMA expression in arachnoid, cerebral cortex and white matter arterioles was greater in the Preclinical AD group than in the Normal and FTD groups. The plaques were not associated with amyloid angiopathy or other vascular disease in this group. SMA expression in the brains of the Normal group was intermediate between the Preclinical AD and FTD groups. All 3 groups exhibited much greater SMA expression than in our previous report. The presence of frequent plaques and increased arteriolar SMA expression in the brains of non-demented subjects suggest that increased SMA expression might represent a physiologic response to neurodegeneration that could prevent or delay overt expression dementia in AD. PMID:19287310
Post-traumatic syringomyelia: CSF hydrodynamic changes following spinal cord injury are the driving force in the development of PTSM.
Shields, Christopher B; Zhang, Yi Ping; Shields, Lisa B E
Post-traumatic syringomyelia (PTSM) is a disorder that occurs infrequently following spinal cord injury (SCI), characterized by progressive neurological deterioration resulting from syrinx expansion originating in proximity to the traumatic epicenter. Several pathogenetic factors are associated with this disorder, however, the precise mechanism of the development of PTSM is controversial. Combined anatomical alterations and molecular changes following trauma to the spinal cord and arachnoid participate in the development of this condition. These factors include narrowing or obstruction of the subarachnoid space (SAS), central canal occlusion, myelomalacia, and alterations in intramedullary water permeability. If a patient sustains a SCI with delayed progressive deterioration in neurological function, in association with the MRI appearance of syringomyelia (SM), the diagnosis of PTSM is straightforward. The treatment of PTSM has not undergone any significant changes recently. The surgical treatment of PTSM consists of reconstructing the SAS or shunting fluid away from the syrinx to other locations. The advantages and disadvantages of each procedure will be discussed. With greater understanding of the mechanisms contributing to the development of SM, including advanced diagnostic methods and further advances in the development of artificial dural and shunting tubing, future therapies of PTSM will be more effective and long-lasting. Incorporation of alterations of AQP4 expression provides an intriguing possibility for future treatment of PTSM. Copyright © 2012 Elsevier B.V. All rights reserved.
Atretic cephalocele: the tip of the iceberg.
Martinez-Lage, J F; Sola, J; Casas, C; Poza, M; Almagro, M J; Girona, D G
Atretic cephalocele appears as an unimportant and benign lesion. This malformation consists of meningeal and vestigial tissues (arachnoid, glial, or central nervous system rests). The authors report the findings in 16 cases (seven parietal and nine occipital) of rudimentary cephaloceles. Twelve patients presented with associated brain abnormalities detected by either computerized tomography (CT) or magnetic resonance imaging (MR). Nine lesions also exhibited an anomalous vascular component demonstrated by CT or MR imaging or at surgery. The existence of this tiny malformation in five cases was the main diagnostic clue to a severe complex of cerebral anomalies, namely cerebro-oculomuscular (Walker-Warburg) syndrome. An occipital location of the atretic cephalocele was associated with the worst prognosis, with only two children developing normally. However, a parietal location carried a better prognosis, which is contrary to the outcome reported in the current literature. The authors classify atretic cephaloceles into two types based on histological examination of the surgical specimens, and suggest that these types represent different stages in the development of this malformation. It is concluded that, in the evaluation of the atretic cephalocele, the neurosurgeon is obliged to proceed to a detailed neuroradiological study of the patient and that the prognosis does not depend on the existence of the cephalocele itself, but rather on associated "occult" brain anomalies.
Spinal cord injury arising in anaesthesia practice.
Hewson, D W; Bedforth, N M; Hardman, J G
Spinal cord injury arising during anaesthetic practice is a rare event, but one that carries a significant burden in terms of morbidity and mortality. In this article, we will review the pathophysiology of spinal cord injury. We will then discuss injuries relating to patient position, spinal cord hypoperfusion and neuraxial techniques. The most serious causes of spinal cord injury - vertebral canal haematoma, spinal epidural abscess, meningitis and adhesive arachnoiditis - will be discussed in turn. For each condition, we draw attention to practical, evidence-based measures clinicians can undertake to reduce their incidence, or mitigate their severity. Finally, we will discuss transient neurological symptoms. Some cases of spinal cord injury during anaesthesia can be ascribed to anaesthesia itself, arising as a direct consequence of its conduct. The injury to a spinal nerve root by inaccurate and/or incautious needling during spinal anaesthesia is an obvious example. But in many cases, spinal cord injury during anaesthesia is not caused by, related to, or even associated with, the conduct of the anaesthetic. Surgical factors, whether direct (e.g. spinal nerve root damage due to incorrect pedicle screw placement) or indirect (e.g. cord ischaemia following aortic surgery) are responsible for a significant proportion of spinal cord injuries that occur concurrently with the delivery of regional or general anaesthesia. © 2018 The Association of Anaesthetists of Great Britain and Ireland.
Unusual Phenotypic Features in a Patient with a Novel Splice Mutation in the GHRHR Gene
Hilal, Latifa; Hajaji, Yassir; Vie-Luton, Marie-Pierre; Ajaltouni, Zeina; Benazzouz, Bouchra; Chana, Maha; Chraïbi, Adelmajid; Kadiri, Abdelkrim; Amselem, Serge; Sobrier, Marie-Laure
Isolated growth hormone deficiency (IGHD) may be of genetic origin. One of the few genes involved in that condition encodes the growth hormone releasing hormone receptor (GHRHR) that, through its ligand (GHRH), plays a pivotal role in the GH synthesis and secretion by the pituitary. Our objective is to describe the phenotype of two siblings born to a consanguineous union presenting with short stature (IGHD) and Magnetic Resonance Imaging (MRI) abnormalities, and to identify the molecular basis of this condition. Our main outcome measures were clinical and endocrinological investigations, MRI of the pituitary region, study of the GHRHR gene sequence and transcripts. In both patients, the severe growth retardation (−5SD) was combined with anterior pituitary hypoplasia. In addition to these classical phenotypic features for IGHD, one of the patients had a Chiari I malformation, an arachnoid cyst, and a dysmorphic anterior pituitary. A homozygous sequence variation in the consensus donor splice site of intron 1 (IVS1 + 2T > G) of the GHRHR gene was identified in both patients. Using in vitro transcription assay, we showed that this mutation results in abnormal splicing of GHRHR transcripts. In this report, which broadens the phenotype associated with GHRHR defects, we discuss the possible role of the GHRHR in the proper development of extrapituitary structures, through a mechanism that could be direct or secondary to severe GH deficiency. PMID:18297129
Pathologic Progression, Possible Origin, and Management of Multiple Primary Intracranial Neuroendocrine Carcinomas.
Cao, Jingwei; Xu, Wenzhe; Du, Zhenhui; Sun, Bin; Li, Feng; Liu, Yuguang
Primary intracranial neuroendocrine carcinomas (NECs) are extremely rare malignant tumors with no previous reports of multiple ones in the literatures. The clinical presentation, preoperative and reexamined magnetic resonance imaging findings, as well as histopathologic studies of a 56-year-old female subject with multiple intracranial NECs mimicking multiple intracranial meningiomas, who underwent 3 operations with left parietal craniotomy, right occipital parietal craniotomy, and left frontal craniotomy, separately and chronologically, are presented in this article. Noteworthy, the first and second tumors were confirmed as NECs exhibiting histologic characteristics of typical anaplastic meningiomas with features of whorl formation, while the third tumor was a typical NEC with features of organoid cancer nests. In other words, the first 2 lesions were diagnosed as meningioma as opposed to NEC. It was only after the third surgery that the pathology for the first 2 cases was reviewed and had a revised diagnosis. After the third surgical resection, the patient further received whole brain radiotherapy and systemic chemotherapy (temozolomide combined with YH-16). At her 10-month follow-up, the patient achieved a good outcome. Multiple primary intracranial NECs are extremely rare. The tumor might be of arachnoidal or leptomeningeal origin, with histologic patterns that might lead to transformation and/or progression. Maximal surgical resection is warranted for symptomatic mass effect. Postoperative adjuvant treatments including radiotherapy and chemotherapy should be a recommended therapeutic modality. Copyright © 2017 Elsevier Inc. All rights reserved.
Use of collagen film as a dural substitute: preliminary animal studies.
Collins, R L; Christiansen, D; Zazanis, G A; Silver, F H
Cadaver grafts, laminated metallic materials, and synthetic fabrics have been evaluated as dural substitutes. Use of cadaver tissues is limited by fear of transmission of infectious disease while use of synthetic materials is associated with implant encapsulation and foreign body reactions. The purpose of this study is to evaluate the use of collagen film as a dural substitute. Collagen films prepared from bovine skin were used to replace the dura of rabbits and histological observations were made at 16, 28, 42, and 56 days postimplantation. Controls consisted of dura that was removed and then reattached. Control dura showed no signs of inflammation or adhesion to underlying tissue at 16 and 28 days postimplantation. By 56 days postimplantation, extensive connective tissue deposition was observed in close proximity to adjacent bone as well as pia arachnoid adhesions. Implanted collagen film behaved in a similar manner to control dura showing minimal inflammatory response at all time periods. At 56 days postimplantation collagen film appeared strongly infiltrated by connective tissue cells that deposited new collagen. The results of this study suggest that a reconstituted type I collagen film crosslinked with cyanamide acts as a temporary barrier preventing loss of fluid and adhesion formation. It is replaced after approximately 2 months with host collagen with limited inflammatory and fibrotic complications. Further studies are needed to completely characterize the new connective tissue formed as well as long-term biocompatibility and functioning of a reconstituted collagen dural substitute.
Thermal protection during percutaneous thermal ablation procedures: interest of carbon dioxide dissection and temperature monitoring.
Buy, Xavier; Tok, Chung-Hong; Szwarc, Daniel; Bierry, Guillaume; Gangi, Afshin
Percutaneous image-guided thermal ablation of tumor is widely used, and thermal injury to collateral structures is a known complication of this technique. To avoid thermal damage to surrounding structures, several protection techniques have been reported. We report the use of a simple and effective protective technique combining carbon dioxide dissection and thermocouple: CO(2) displaces the nontarget structures, and its low thermal conductivity provides excellent insulation; insertion of a thermocouple in contact with vulnerable structures achieves continuous thermal monitoring. We performed percutaneous thermal ablation of 37 tumors in 35 patients (4 laser, 10 radiofrequency, and 23 cryoablations) with protection of adjacent vulnerable structures by using CO(2) dissection combined with continuous thermal monitoring with thermocouple. Tumor locations were various (19 intra-abdominal tumors including 4 livers and 9 kidneys, 18 musculoskeletal tumors including 11 spinal tumors). CO(2) volume ranged from 10 ml (epidural space) to 1500 ml (abdominal). Repeated insufflations were performed if necessary, depending on the information given by the thermocouple and imaging control. Dissection with optimal thermal protection was achieved in all cases except two patients where adherences (one postoperative, one arachnoiditis) blocked proper gaseous distribution. No complication referred to this technique was noted. This safe, cost-effective, and simple method increases the safety and the success rate of percutaneous thermal ablation procedures. It also offers the potential to increase the number of tumors that can be treated via a percutaneous approach.
Efficacy and Toxicity of Intrathecal Liposomal Cytarabine in First-line Therapy of Childhood Acute Lymphoblastic Leukemia.
Levinsen, Mette; Harila-Saari, Arja; Grell, Kathrine; Jonsson, Olafur Gisli; Taskinen, Mervi; Abrahamsson, Jonas; Vettenranta, Kim; Åsberg, Ann; Risteli, Juha; Heldrup, Jesper; Schmiegelow, Kjeld
We investigated efficacy and toxicity of replacing conventional triple (cytarabine, methotrexate, and hydrocortisone) intrathecal therapy (TIT) with liposomal cytarabine during maintenance therapy among 40 acute lymphoblastic leukemia patients. Twenty-eight of 29 patients in the TIT arm received TIT and 9/11 in the liposomal cytarabine arm received liposomal cytarabine. Arachnoiditis occurred in all initial 5 patients given liposomal cytarabine and intrathecal prednisolone succinate. Subsequently liposomal cytarabine was given with systemic dexamethasone. Neurotoxicity occurred at 6/27 liposomal cytarabine administrations with concomitant dexamethasone (22%). More liposomal cytarabine-treated patients experienced neurotoxicity in relation to intrathecal therapy during at least 1 cycle compared with TIT-treated patients (6/9 [67%] vs. 3/28 [11%], P=0.002). Apart from intermittent lower extremity sensory pain in 1 liposomal cytarabine-treated patient, no permanent adverse neurological sequelae were observed. In intention-to-treat analysis, projected 5-year event-free survival (pEFS-5y) was borderline higher for patients in the liposomal cytarabine arm compared with the TIT arm (1.0 vs. 0.69, P=0.046). However, pEFS-5y and projected 5-year relapse-free survival did not differ signficantly between patients treated with liposomal cytarabine or TIT (1.0 vs. 0.73, P=0.10; 1.0 vs. 0.76, P=0.12). Larger prospective trials are needed to explore whether liposomal cytarabine should be used as first-line prevention of relapse.
Modelling emergency decisions: recognition-primed decision making. The literature in relation to an ophthalmic critical incident.
Bond, Susan; Cooper, Simon
To review and reflect on the literature on recognition-primed decision (RPD) making and influences on emergency decisions with particular reference to an ophthalmic critical incident involving the sub-arachnoid spread of local anaesthesia following the peribulbar injection. This paper critics the literature on recognition-primed decision making, with particular reference to emergency situations. It illustrates the findings by focussing on an ophthalmic critical incident. Systematic literature review with critical incident reflection. Medline, CINAHL and PsychINFO databases were searched for papers on recognition-primed decision making (1996-2004) followed by the 'snowball method'. Studies were selected in accordance with preset criteria. A total of 12 papers were included identifying the recognition-primed decision making as a good theoretical description of acute emergency decisions. In addition, cognitive resources, situational awareness, stress, team support and task complexity were identified as influences on the decision process. Recognition-primed decision-making theory describes the decision processes of experts in time-bound emergency situations and is the foundation for a model of emergency decision making (Fig. 2). Decision theory and models, in this case related to emergency situations, inform practice and enhance clinical effectiveness. The critical incident described highlights the need for nurses to have a comprehensive and in-depth understanding of anaesthetic techniques as well as an ability to manage and resuscitate patients autonomously. In addition, it illustrates how the critical incidents should influence the audit cycle with improvements in patient safety.
Management of a case with misdiagnosed spinal dural arterio-venous fistula.
Lien, Chia-Yi; Lui, Chun-Chung; Lu, Cheng-Hsien; Chang, Wen-Neng
Spinal dural arterio-venous fistula (SDAVF) is an uncommon and easily misdiagnosed vascular malformation. We aimed to report the diagnosis and management of a case with SDAVF. A 62-year-old man suffered from acute paraparesis about 15 months before this study. He underwent a neurosurgical procedure for herniated discs of the cervical spine at that time but there was no relief and the symptoms worsened despite the surgery. Neurologically, he had spastic paraparesis and decreased vibration sensation of the lower limbs. Spinal magnetic resonance imaging (MRI) revealed intra-medullary hyper-intensity lesion at T8 to T10 levels and tubular-like signal void structures in the corresponding posterior sub-arachnoid space. Further trans-arterial angiography through right T6 intercostal artery catheterization revealed engorged veins, thereby confirming the diagnosis of SDAVF. The patient was treated via endovascular embolization (18% Onyx, EV3TM MIT, Bonn, Germany) through spinal angiography and the results showed a marked decrease in engorged veins. After a 4-month follow-up, the patient was symptomatic but stable. Follow-up MRI showed a complete disappearance of the hyper-intensity change of the spinal cord. Spinal MR angiography did not reveal any recurrence of SDAVF. This case study demonstrated the easily misdiagnosed state of SDAVF. Serial neuroimage studies including spinal MRI, endovascular embolization through spinal angiography and MR angiography can be useful tools for its diagnostic confirmation, management and follow-up study.
Extended endoscopic transsphenoidal approach infrachiasmatic corridor.
Ceylan, Savas; Anik, Ihsan; Koc, Kenan; Cabuk, Burak
An extended endoscopic transsphenoidal approach is required for skull base lesions extending to the suprasellar area. Inferior approach using the infrachiasmatic corridor allows access to the lesions through the tumor growth that is favorable for the extended transsphenoidal approaches. Infrachiasmatic corridor is a safer route for the inferior approaches that is made up by basal arachnoid membrane and Liliequist's membrane with its leaves (diencephalic and mesencephalic leaf). This area extends from the optic canal and tuberculum sella to the corpus mamillare. We performed extended endoscopic approach using the infrachiasmatic corridor in 52 cases, including tuberculum sella meningiomas (n:23), craniopharyngiomas (n:16), suprasellar Rathke's cleft cyst (n:6), pituitary adenoma (n:2), fibrous dysplasia (n:1), infundibular granulosa cell tumor (n:2), and epidermoid tumor (n:2). Total resection was achieved in 17 of 23 (74%) with tuberculum sellae meningioma using infrachiasmatic approach. Twenty patients presented with visual disorders and 14 of them improved. There were two postoperative cerebrospinal fluid (CSF) leakages and one transient diabetes insipidus and one permanent diabetes insipidus. Sixteen patients were operated on by the infrachiasmatic approach for craniopharyngiomas. Improvement was reached in seven of eight patients presented with visual disorders. Complete tumor resection was performed in 10 of 16 cases and cyst aspiration in 4 cases, and there were remnants in two cases. Postoperative CSF leakage was seen in two patients. Infrachiasmatic corridor provides an easier and safer inferior route for the removal of middle midline skull base lesions in selected cases.
Neuroimaging of Dandy-Walker malformation: new concepts.
Correa, Gustavo Gumz; Amaral, Lázaro Faria; Vedolin, Leonardo Modesti
Dandy-Walker malformation (DWM) is the most common human cerebellar malformation, characterized by hypoplasia of the cerebellar vermis, cystic dilation of the fourth ventricle, and an enlarged posterior fossa with upward displacement of the lateral sinuses, tentorium, and torcular. Although its pathogenesis is not completely understood, there are several genetic loci related to DWM as well as syndromic malformations and congenital infections. Dandy-Walker malformation is associated with other central nervous system abnormalities, including dysgenesis of corpus callosum, ectopic brain tissue, holoprosencephaly, and neural tube defects. Hydrocephalus plays an important role in the development of symptoms and neurological outcome in patients with DWM, and the aim of surgical treatment is usually the control of hydrocephalus and the posterior fossa cyst. Imaging modalities, especially magnetic resonance imaging, are crucial for the diagnosis of DWM and distinguishing this disorder from other cystic posterior fossa lesions. Persistent Blake's cyst is seen as a retrocerebellar fluid collection with cerebrospinal fluid signal intensity and a median line communication with the fourth ventricle, commonly associated with hydrocephalus. Mega cisterna magna presents as an extraaxial fluid collection posteroinferior to an intact cerebellum. Retrocerebellar arachnoid cysts frequently compress the cerebellar hemispheres and the fourth ventricle. Patients with DWM show an enlarged posterior fossa filled with a cystic structure that communicates freely with the fourth ventricle and hypoplastic vermis. Comprehension of hindbrain embryology is of utmost importance for understanding the cerebellar malformations, including DWM, and other related entities.
Expanded Endoscopic Endonasal Resection of Retrochiasmatic Craniopharyngioma.
Davanzo, Justin R; Goyal, Neerav; Zacharia, Brad E
This video abstract demonstrates the use of the expanded endoscopic endonasal approach for the resection of a retrochiasmatic craniopharyngioma. These tumors are notoriously difficult to treat, and many approaches have been tried to facilitate safe and effective resection. The endoscopic endonasal approach has been increasingly utilized for selected sellar/suprasellar pathology. We present the case of a 39-year-old man who was found to have a cystic, partially calcified suprasellar mass consistent with a craniopharyngioma. To facilitate robust skull base repair, a vascularized nasoseptal flap was harvested. A wide sphenoidotomy was performed and the sella and tuberculum were exposed. After the dural opening and arachnoid dissection, the stalk was identified, merging seamlessly with the tumor capsule. The lesion was then internally debulked with the use of an ultrasonic aspirator. The capsule was then dissected off of the optic chiasm, thalamus, and hypothalamus. The cavity was inspected with an angled endoscope to ensure complete resection. A multilayered reconstruction was performed using autologous fascia lata, the previously harvested nasoseptal flap, and dural sealant. Postoperatively, the patient did have expected panhypopituitarism but remained neurologically intact and had improvement in his vision. In conclusion, this video demonstrates how an expanded endonasal approach can be used to safely resect a craniopharyngioma, even when in close proximity to delicate structures such as the optic chiasm. The link to the video can be found at: https://youtu.be/tahjHmrXhc4 .
Virus spread and initial pathological changes in the nervous system in genital herpes simplex virus type 2 infection in mice. A correlative immunohistochemical, light and electron microscopic study.
Georgsson, G; Martin, J R; Stoner, G L; Webster, H F
Mice were infected by the vaginal route with the MS strain of herpes simplex virus type 2 (HSV-2). Serial vaginal cultures were used to confirm infection and to select mice for this study. Two mice were killed by perfusion on days 2-6 post infection (p.i.) and lumbar and sacral cord with cauda were fixed and embedded for electron microscopy. Semithin Epon-sections were stained for viral antigen using a rabbit anti-HSV-2 antiserum and the Avidin-Biotin (ABC) method. Thin sections from antigen-positive blocks were examined by electron microscopy, and the number and types of infected cells detected by these two methods were compared. A good correlation was found between detection of infected cells by these methods. Infected cells included neurons of dorsal root ganglia and spinal cord, satellite cells of dorsal root ganglia, non-myelinating Schwann cells, astrocytes, oligodendrocytes and arachnoidal cells. Infected cells were first detected in the cauda on day 3 p.i. and in the spinal cord on day 5 p.i. The temporal and spatial distribution of infected cells was consistent with neural spread to and within the CNS. The pathological lesions showed a good correlation with the distribution and number of infected cells and are probably due to a direct virus effect. The similar sensitivity of the Epon-ABC method to electron microscopy in detecting infected cells indicates that this method may have useful applications in both experimental and diagnostic work.
Anatomy of the Spinal Meninges.
Sakka, Laurent; Gabrillargues, Jean; Coll, Guillaume
The spinal meninges have received less attention than the cranial meninges in the literature, although several points remain debatable and poorly understood, like their phylogenesis, their development, and their interactions with the spinal cord. Their constancy among the chordates shows their crucial importance in central nervous system homeostasis and suggests a role far beyond mechanical protection of the neuraxis. This work provides an extensive study of the spinal meninges, from an overview of their phylogenesis and embryology to a descriptive and topographic anatomy with clinical implications. It examines their involvement in spinal cord development, functioning, and repair. This work is a review of the literature using PubMed as a search engine on Medline. The stages followed by the meninges along the phylogenesis could not be easily compared with their development in vertebrates for methodological aspects and convergence processes throughout evolution. The distinction between arachnoid and pia mater appeared controversial. Several points of descriptive anatomy remain debatable: the functional organization of the arterial network, and the venous and lymphatic drainages, considered differently by classical anatomic and neuroradiological approaches. Spinal meninges are involved in neurodevelopment and neurorepair producing neural stem cells and morphogens, in cerebrospinal fluid dynamics and neuraxis functioning by the synthesis of active molecules, and the elimination of waste products of central nervous system metabolism. The spinal meninges should be considered as dynamic functional formations evolving over a lifetime, with ultrastructural features and functional interactions with the neuraxis remaining not fully understood.
A spinal thecal sac constriction model supports the theory that induced pressure gradients in the cord cause edema and cyst formation.
Josephson, A; Greitz, D; Klason, T; Olson, L; Spenger, C
Spinal cord cysts are a devastating condition that occur secondary to obstructions of the spinal canal, which may be caused by congenital malformations, trauma, spinal canal stenosis, tumors, meningitis, or arachnoiditis. A hypothesis that could explain how spinal cord cysts form in these situations has been presented recently. Therefore, a novel spinal thecal sac constriction model was implemented to test various aspects of this hypothesis. Thecal sac constriction was achieved by subjecting rats to an extradural silk ligature at the T8 spinal cord level. Rats with complete spinal cord transection served as a second model for comparison. The animals underwent high-resolution magnetic resonance imaging and histological analysis. Thecal sac constriction caused edema cranial and caudal to the ligation within 3 weeks, and cysts developed after 8 to 13 weeks. In contrast, cysts in rats with spinal cord transection were located predominantly in the cranial spinal cord. Histological sections of spinal cords confirmed the magnetic resonance imaging results. Magnetic resonance imaging provided the specific advantage of enabling characterization of events as they occurred repeatedly over time in the spinal cords of individual living animals. The spinal thecal sac constriction model proved useful for investigation of features of the cerebrospinal fluid pulse pressure theory. Edema and cyst distributions were in accordance with this theory. We conclude that induced intramedullary pressure gradients originating from the cerebrospinal fluid pulse pressure may underlie cyst formation in the vicinity of spinal canal obstructions and that cysts are preceded by edema.
Endoscopy in the treatment of slit ventricle syndrome
Zheng, Jiaping; Chen, Guoqiang; Xiao, Qing; Huang, Yiyang; Guo, Yupeng
The present study aimed to investigate the efficacy of endoscopy in the treatment of post-shunt placement for slit ventricle syndrome (SVS). Endoscopic surgery was performed on 18 patients with SVS between October 2004 and December 2012. Sex, age, causes of the hydrocephalus, ventricular size and imaging data were collected and analyzed. All patients were divided into two groups according to ventricular size and underwent endoscopic surgeries, including endoscopic third ventriculostomy (ETV), endoscopic aqueductoplasty and cystocisternostomy. All treated patients were observed postoperatively for a period of 2 to 3 weeks, and outpatient follow-up was subsequently scheduled for >12 months. Clinical results, including catheter adherence, shunt removal and complications, were analyzed during the follow-up period. The success rate of endoscopic surgery was indicated to be 82.7%. Syndromes caused by aqueductal stenosis in 15 patients who underwent ETV were relieved; however, syndromes in the 3 patients with cerebral cysticercosis, suprasellar arachnoid cysts, pinea larea glioma and communicating hydrocephalus, respectively, were not relieved and underwent shunt placement again. Brain parenchyma, choroid plexus and ependymal tissue were the predominant causes for catheter obstruction and the obstruction rate was indicated to be 77.8% (14/18). Complications, such as pseudobulbar paralysis, infection and intraventricular hemorrhage arose in 3 patients. The present study indicates that endoscopic treatments are effective and ETV may be considered as a recommended option in the treatment of post-shunt placement SVS in hydrocephalus patients. PMID:29042922
Two cases of sarcoidosis presenting as longitudinally extensive transverse myelitis.
Scott, Amanda Mary; Yinh, Janeth; McAlindon, Timothy; Kalish, Robert
Neurosarcoidosis is uncommon with an incidence of approximately 5 to 15%. Central nervous system involvement can be divided into brain and spinal cord neurosarcoidosis. Spinal cord sarcoidosis is extremely rare, occurring in less than 1% of all sarcoidosis cases. Its manifestations may include cauda equina syndrome, radiculopathy, syringomyelia, cord atrophy, arachnoiditis, and myelopathy or transverse myelitis. We highlight two cases of spinal cord sarcoidosis, each presenting with longitudinally extensive transverse myelitis, that demonstrate the dilemmas that physicians face with regard to diagnosis and treatment. Given its rarity and the diversity of possible manifestations, establishing the diagnosis of spinal cord sarcoidosis is often very difficult. Extensive evaluation must be conducted to rule out primary neurologic, primary rheumatologic, infectious, and neoplastic diseases. MRI often demonstrates hyperintensity on T2-weighted images and enhancement following gadolinium administration. CSF analysis most consistently shows a lymphocytic pleocytosis and elevated proteins. While these less invasive investigations may be helpful, the gold standard for diagnosis is biopsy of neurologic or non-neurologic tissue confirming the presence of non-caseating granulomas. Evidence-based guidelines for the treatment of transverse myelitis secondary to sarcoidosis are lacking due to its rarity; therefore, therapy is based on expert and anecdotal experience and usually consists of high doses of steroids in combination with various immunosuppressive agents. The use of infliximab in particular appears promising, but there is a need for further investigation into the ideal treatment regimen.
Neurologic complications of intrathecal liposomal cytarabine administered prophylactically to patients with non-Hodgkin lymphoma.
Gállego Pérez-Larraya, Jaime; Palma, José Alberto; Carmona-Iragui, María; Fernández-Torrón, Roberto; Irimia, Pablo; Rodríguez-Otero, Paula; Panizo, Carlos; Martínez-Vila, Eduardo
Central nervous system (CNS) prophylaxis is required during initial treatment of non-Hodgkin lymphoma (NHL) subtypes that carry a high risk of CNS involvement. Intrathecal (IT) liposomal cytarabine, a formulation with prolonged half-life, has been shown to be safe and effective in the treatment of meningeal disease in patients with high-grade lymphoma. We retrospectively reviewed all adult patients with high-grade NHL that received prophylactic therapy with IT liposomal cytarabine and developed neurologic complications in our institution between April 2007 and May 2009. We recorded information on hospital admission, chemotherapy regimens, clinical features, neuroimaging, cerebrospinal fluid, neurophysiology data, and outcome. Neurotoxicity was graded according to the National Cancer Institute Common Toxicity Criteria (NCI-CTC). Four of fourteen patients (28%) developed moderate or severe neurotoxicity (grades 2 and 3 of the NCI-CTC), manifested as conus medullaris/cauda equine syndrome or pseudotumour cerebri-like syndrome, after a median of 3.5 IT courses of liposomal cytarabine. All patients had received corticosteroids to prevent arachnoiditis. Liposomal cytarabine given via the IT route, even with concomitant corticosteroid administration, can result in significant neurotoxicity in some patients. We discuss the potential pathogenesis of these effects and suggest hypothetical therapeutic measures to prevent these complications. Specialists should be aware of these possible complications when administering prophylactic IT liposomal cytarabine in high-grade NHL patients, and additional prospective studies should be conducted to more clearly delineate the frequency and characteristics of these complications.
The collagenic architecture of human dura mater.
Protasoni, Marina; Sangiorgi, Simone; Cividini, Andrea; Culuvaris, Gloria Tiffany; Tomei, Giustino; Dell'Orbo, Carlo; Raspanti, Mario; Balbi, Sergio; Reguzzoni, Marcella
Human dura mater is the most external meningeal sheet surrounding the CNS. It provides an efficient protection to intracranial structures and represents the most important site for CSF turnover. Its intrinsic architecture is made up of fibrous tissue including collagenic and elastic fibers that guarantee the maintenance of its biophysical features. The recent technical advances in the repair of dural defects have allowed for the creation of many synthetic and biological grafts. However, no detailed studies on the 3D microscopic disposition of collagenic fibers in dura mater are available. The authors report on the collagenic 3D architecture of normal dura mater highlighting the orientation, disposition in 3 dimensions, and shape of the collagen fibers with respect to the observed layer. Thirty-two dura mater specimens were collected during cranial decompressive surgical procedures, fixed in 2.5% Karnovsky solution, and digested in 1 N NaOH solution. After a routine procedure, the specimens were observed using a scanning electron microscope. The authors distinguished the following 5 layers in the fibrous dura mater of varying thicknesses, orientation, and structures: bone surface, external median, vascular, internal median, and arachnoid layers. The description of the ultrastructural 3D organization of the different layers of dura mater will give us more information for the creation of synthetic grafts that are as similar as possible to normal dura mater. This description will be also related to the study of the neoplastic invasion.
Oblique Intrathecal Injection in Lumbar Spine Surgery: A Technical Note.
Jewett, Gordon A E; Yavin, Daniel; Dhaliwal, Perry; Whittaker, Tara; Krupa, JoyAnne; Du Plessis, Stephan
Intrathecal morphine (ITM) is an efficacious method of providing postoperative analgesia and reducing pain associated complications. Despite adoption in many surgical fields, ITM has yet to become a standard of care in lumbar spine surgery. Spine surgeons' reticence to make use of the technique may in part be attributed to concerns of precipitating a cerebrospinal fluid (CSF) leak. Herein we describe a method for oblique intrathecal injection during lumbar spine surgery to minimize risk of CSF leak. The dural sac is penetrated obliquely at a 30° angle to offset dural and arachnoid puncture sites. Oblique injection in instances of limited dural exposure is made possible by introducing a 60° bend to a standard 30-gauge needle. The technique was applied for injection of ITM or placebo in 104 cases of lumbar surgery in the setting of a randomized controlled trial. Injection was not performed in two cases (2/104, 1.9%) following preinjection dural tear. In the remaining 102 cases no instances of postoperative CSF leakage attributable to oblique intrathecal injection occurred. Three cases (3/102, 2.9%) of transient CSF leakage were observed immediately following intrathecal injection with no associated sequelae or requirement for postsurgical intervention. In two cases, the observed leak was repaired by sealing with fibrin glue, whereas in a single case the leak was self-limited requiring no intervention. Oblique dural puncture was not associated with increased incidence of postoperative CSF leakage. This safe and reliable method of delivery of ITM should therefore be routinely considered in lumbar spine surgery.
Success criteria in pediatric neuroendoscopic procedures. Proposal for classification of results after 67 operations.
Ros, Bienvenido; Romero, Lorena; Ibáñez, Guillermo; Iglesias, Sara; Rius, Francisca; Pérez, Sandra; Arráez, Miguel A
Controversial issues exist concerning criteria for patient selection and long-term success in pediatric neuroendoscopic procedures. We designed a classification of success grades applicable to high-pressure and chronic hydrocephalus and also to those cases in which different endoscopic maneuvers are performed during the same procedure. We then evaluated the success rate and complications in our series. A total of 59 patients underwent 67 neuroendoscopic procedures between January 2003 and January 2011. A retrospective study was made of the preoperative history, operative reports, and postoperative imaging findings and medical records. A 5-grade scale was developed to assess the type of success depending on clinical and radiological data. Complications related to the surgical procedure were also recorded. Two patients were excluded from the success analysis due to insufficient follow-up time. The final results for the first procedures in 57 patients were complete and permanent success (grade I) in 49.1%, complete but transitory success (grade II) in 10.5%, partial success (grade III) in 12.3%, doubtful success (grade IV) in 5.3%, and failure (grade V) in 22.8%. In eight cases a second procedure followed the failure of the first: grade I success was achieved in seven cases (87.5%) and grade V in one case (12.5%). The highest success rates were achieved in cases of hydrocephalus caused by tumors or arachnoid cysts and the lowest in slit ventricle syndrome. A common classification of degrees of success, such as that proposed here, would aid the development of comparative and cooperative studies.
Bolstering the Nasoseptal Flap Using Sphenoid Sinus Fat Packing: A Technical Case Report.
Abou-Al-Shaar, Hussam; Zaidi, Hasan A; Cote, David J; Laws, Edward R
Resection of extensive skull base lesions often necessitates relatively large dural openings and arachnoid, resulting in skull base defects with the potential for a postoperative cerebrospinal fluid leak. A nasoseptal flap (NSF) is a vascularized graft that has greatly diminished the incidence of cerebrospinal fluid leak. Annealing of flaps against the ventral skull base can be tenuous within the first few days after surgery. We report the use of sphenoid sinus fat packing as a buttress to support the nasoseptal flap during skull base reconstruction. A 37-year-old man presented with pan-hypopituitarism, bitemporal hemianopsia, and imaging consistent with a craniopharyngioma. He underwent an endoscopic endonasal approach with resection of the planum and tuberculum sphenoidale for resection of this mass. An NSF was harvested, and a combination of suprasellar fat packing, tensor fasciae lata graft, and Porex plate along with the flap were used to reconstruct the skull base. Postoperatively, he precipitously experienced copious rhinorrhea necessitating surgical re-exploration. A redundant segment of the NSF had retracted into the sphenoid sinus, and was no longer supported against the ventral skull base. We repositioned the NSF and used sphenoid sinus fat packing to help support the graft against the ventral skull base. A postoperative computed tomographic scan demonstrated a clear delineation between the vascularized graft and the fat packing, confirming proper positioning of the flap. Sphenoid sinus fat packing can be an important technical adjunct in bolstering the nasoseptal flap against the ventral skull base in the tenuous early perioperative period. Copyright © 2016 Elsevier Inc. All rights reserved.
Three-dimensional reconstruction of the topographical cerebral surface anatomy for presurgical planning with free OsiriX Software.
Harput, Mehmet V; Gonzalez-Lopez, Pablo; Türe, Uğur
During surgery for intrinsic brain lesions, it is important to distinguish the pathological gyrus from the surrounding normal sulci and gyri. This task is usually tedious because of the pia-arachnoid membranes with their arterial and venous complexes that obscure the underlying anatomy. Moreover, most tumors grow in the white matter without initially distorting the cortical anatomy, making their direct visualization more difficult. To create and evaluate a simple and free surgical planning tool to simulate the anatomy of the surgical field with and without vessels. We used free computer software (OsiriX Medical Imaging Software) that allowed us to create 3-dimensional reconstructions of the cerebral surface with and without cortical vessels. These reconstructions made use of magnetic resonance images from 51 patients with neocortical supratentorial lesions operated on over a period of 21 months (June 2011 to February 2013). The 3-dimensional (3-D) anatomic images were compared with the true surgical view to evaluate their accuracy. In all patients, the landmarks determined by 3-D reconstruction were cross-checked during surgery with high-resolution ultrasonography; in select cases, they were also checked with indocyanine green videoangiography. The reconstructed neurovascular structures were confirmed intraoperatively in all patients. We found this technique to be extremely useful in achieving pure lesionectomy, as it defines tumor's borders precisely. A 3-D reconstruction of the cortical surface can be easily created with free OsiriX software. This technique helps the surgeon perfect the mentally created 3-D picture of the tumor location to carry out cleaner, safer surgeries.
Detection of cerebrospinal fluid leakage: initial experience with three-dimensional fast spin-echo magnetic resonance myelography.
Tomoda, Y; Korogi, Y; Aoki, T; Morioka, T; Takahashi, H; Ohno, M; Takeshita, I
The pathogenesis of cerebrospinal fluid (CSF) hypovolemia is supposed to be caused by CSF leakage through small dural defects. To compare source three-dimensional (3D) fast spin-echo (FSE) images of magnetic resonance (MR) myelography with radionuclide cisternography findings, and to evaluate the feasibility of MR myelography in the detection of CSF leakage. A total of 67 patients who were clinically suspected of CSF hypovolemia underwent indium-111 radionuclide cisternography, and 27 of those who had direct findings of CSF leakage were selected for evaluation. MR myelography with 3D FSE sequences (TR/TE 6000/203 ms) was performed at the lumbar spine for all patients. We evaluated source images and maximum intensity projection (MIP) images of MR myelography, and the findings were correlated with radionuclide cisternography findings. MR myelography of five healthy volunteers was used as a reference. The MR visibility of the CSF leakage was graded as definite (leakage clearly visible), possible (leakage poorly seen), or absent (not shown). CSF leakage was identified with source 3D FSE images in 22 (81.5%) of 27 patients. Of the 22 patients, 16 were graded as definite and six were graded as possible. For the definite cases, 3D FSE images clearly showed the extent of the leaked CSF in the paraspinal structures. In the remaining five patients with absent findings, radionuclide cisternography showed only slight radionuclide activity out of the arachnoid space. Source 3D FSE images of MR myelography seem useful in the detection of CSF leakage. Invasive radionuclide cisternography may be reserved for equivocal cases only.
The risks of epidural and transforaminal steroid injections in the Spine: Commentary and a comprehensive review of the literature
Epstein, Nancy E.
Background: Multiple type of spinal injections, whether epidural/translaminar or transforaminal, facet injections, are offered to patients with/without surgical spinal lesions by pain management specialists (radiologists, physiatrists, and anesthesiologists). Although not approved by the Food and Drug Administration (FDA), injections are being performed with an increased frequency (160%), are typically short-acting and ineffective over the longer-term, while exposing patients to major risks/complications. Methods: For many patients with spinal pain alone and no surgical lesions, the “success” of epidural injections may simply reflect the self-limited course of the disease. Alternatively, although those with surgical pathology may experience transient or no pain relief, undergoing these injections (typically administered in a series of three) unnecessarily exposes them to the inherent risks, while also delaying surgery and potentially exposing them to more severe/permanent neurological deficits. Results: Multiple recent reports cite contaminated epidural steroid injections resulting in meningitis, stroke, paralysis, and death. The Center for Disease Control (CDC) specifically identified 25 deaths (many due to Aspergillosis), 337 patients sickened, and 14,000 exposed to contaminated steroids. Nevertheless, many other patients develop other complications that go unreported/underreported: Other life-threatening infections, spinal fluid leaks (0.4-6%), positional headaches (28%), adhesive arachnoiditis (6-16%), hydrocephalus, air embolism, urinary retention, allergic reactions, intravascular injections (7.9-11.6%), stroke, blindness, neurological deficits/paralysis, hematomas, seizures, and death. Conclusions: Although the benefits for epidural steroid injections may include transient pain relief for those with/without surgical disease, the multitude of risks attributed to these injections outweighs the benefits. PMID:23646278
Central diabetes insipidus: clinical profile and factors indicating organic etiology in children.
Bajpai, Anurag; Kabra, Madhulika; Menon, P S N
To evaluate the profile of children with central diabetes insipidus (DI) and identify factors indicating organic etiology. Retrospective chart review. Tertiary referral hospital. Fifty-nine children with central DI (40 boys, 19 girls). Features of organic and idiopathic central DI were compared using students t test and chi square test. Odds ratio was calculated for factors indicating organic etiology. Diagnosis included post-operative central DI (13, 22%), central nervous system (CNS) malformations (5, 8.6% holoprosencephaly 4 and hydrocephalus 1), histiocytosis (11, 18.6%), CNS pathology (11, 18.6%; craniopharyngioma 3, empty sella 2, germinoma 2, neuro-tuberculosis 2, arachnoid cyst 1 and glioma 1) and idiopathic central DI (19, 32.2%). Children with organic central DI were diagnosed later (7.8+/- 3.1 years against 5.3+/-2.4 years, P=0.03) and had lower height standard deviation score (-2.7+/-1.0 versus -1.0+/- 1.0, P<0.001) compared to idiopathic group. A greater proportion of children with organic central DI had short stature (81.8% against 10.5%, P <0.001, odds ratio 38.25), neurological features (45.5% against 0%, p 0.009) and anterior pituitary hormone deficiency (81.8% against 5.3%, P<0.001, odds ratio 81) compared to idiopathic group. A combination of short stature and onset after five years of age led to discrimination of organic central DI from idiopathic group in all cases. Organic central DI should be suspected in children presenting after the age of five years with growth retardation and features of anterior pituitary deficiency.
Hybrid Monte Carlo-Diffusion Method For Light Propagation in Tissue With a Low-Scattering Region
NASA Astrophysics Data System (ADS)
Hayashi, Toshiyuki; Kashio, Yoshihiko; Okada, Eiji
The heterogeneity of the tissues in a head, especially the low-scattering cerebrospinal fluid (CSF) layer surrounding the brain has previously been shown to strongly affect light propagation in the brain. The radiosity-diffusion method, in which the light propagation in the CSF layer is assumed to obey the radiosity theory, has been employed to predict the light propagation in head models. Although the CSF layer is assumed to be a nonscattering region in the radiosity-diffusion method, fine arachnoid trabeculae cause faint scattering in the CSF layer in real heads. A novel approach, the hybrid Monte Carlo-diffusion method, is proposed to calculate the head models, including the low-scattering region in which the light propagation does not obey neither the diffusion approximation nor the radiosity theory. The light propagation in the high-scattering region is calculated by means of the diffusion approximation solved by the finite-element method and that in the low-scattering region is predicted by the Monte Carlo method. The intensity and mean time of flight of the detected light for the head model with a low-scattering CSF layer calculated by the hybrid method agreed well with those by the Monte Carlo method, whereas the results calculated by means of the diffusion approximation included considerable error caused by the effect of the CSF layer. In the hybrid method, the time-consuming Monte Carlo calculation is employed only for the thin CSF layer, and hence, the computation time of the hybrid method is dramatically shorter than that of the Monte Carlo method.
Hybrid Monte Carlo-diffusion method for light propagation in tissue with a low-scattering region.
Hayashi, Toshiyuki; Kashio, Yoshihiko; Okada, Eiji
The heterogeneity of the tissues in a head, especially the low-scattering cerebrospinal fluid (CSF) layer surrounding the brain has previously been shown to strongly affect light propagation in the brain. The radiosity-diffusion method, in which the light propagation in the CSF layer is assumed to obey the radiosity theory, has been employed to predict the light propagation in head models. Although the CSF layer is assumed to be a nonscattering region in the radiosity-diffusion method, fine arachnoid trabeculae cause faint scattering in the CSF layer in real heads. A novel approach, the hybrid Monte Carlo-diffusion method, is proposed to calculate the head models, including the low-scattering region in which the light propagation does not obey neither the diffusion approximation nor the radiosity theory. The light propagation in the high-scattering region is calculated by means of the diffusion approximation solved by the finite-element method and that in the low-scattering region is predicted by the Monte Carlo method. The intensity and mean time of flight of the detected light for the head model with a low-scattering CSF layer calculated by the hybrid method agreed well with those by the Monte Carlo method, whereas the results calculated by means of the diffusion approximation included considerable error caused by the effect of the CSF layer. In the hybrid method, the time-consuming Monte Carlo calculation is employed only for the thin CSF layer, and hence, the computation time of the hybrid method is dramatically shorter than that of the Monte Carlo method.
Microendoscopic stereotactic-guided percutaneous radiofrequency trigeminal nucleotractotomy.
Teixeira, Manoel Jacobsen; de Almeida, Fabrício Freitas; de Oliveira, Ywzhe Sifuentes Almeida; Fonoff, Erich Talamoni
Over the past few decades, various authors have performed open or stereotactic trigeminal nucleotractotomy for the treatment of neuropathic facial pain resistant to medical treatment. Stereotactic procedures can be performed percutaneously under local anesthesia, allowing intraoperative neurological examination as a method for target refinement. However, blind percutaneous procedures in the region of the atlantooccipital transition carry a considerably high risk of vascular injuries that may bring prohibitive neurological deficit or even death. To avoid such complications, the authors present the first clinical use of microendoscopy to assist percutaneous radiofrequency trigeminal nucleotractotomy. The aim of this article is to demonstrate intradural microendoscopic visualization of the medulla oblongata through an atlantooccipital percutaneous approach. The authors present a case of severe postherpetic facial neuralgia in a patient who underwent the procedure and had satisfactory results. Stereotactic computational image planning for targeting the spinal trigeminal tract and nucleus in the posterolateral medulla was performed, allowing for an accurate percutaneous approach. Immediately before radiofrequency electrode insertion, a fine endoscope was introduced to visualize the structures in the cisterna magna. Microendoscopic visualization offered clear identification of the pial surface of the medulla oblongata and its blood vessels, the arachnoid membrane, cranial nerve rootlets and their entry zone, and larger vessels such as the vertebral arteries and the branches of the posterior inferior cerebellar artery. The initial application of this technique suggests that percutaneous microendoscopy may be useful for particular manipulation of the medulla oblongata, increasing the safety of the procedure and likely improving its effectiveness.
Three-Dimensional Anatomy of the White Matter Fibers of the Temporal Lobe: Surgical Implications.
Pescatori, Lorenzo; Tropeano, Maria Pia; Manfreda, Andrea; Delfini, Roberto; Santoro, Antonio
The aim of this work is to describe in detail the complex 3-dimensional organization of the white matter of the temporal lobe and discuss the surgical implications of the approaches to lesions located into the mesial temporal region and within the temporal horn and the atrium of the lateral ventricles. Sixteen human cerebral hemispheres fixed in a 10% formalin solution for at least 40 days were studied. After removal of the arachnoid membrane, the hemispheres were frozen at -15°C for at least 14 days, and the Klingler technique, which consists of the microscopic dissection and progressive identification of white matter fibers, was performed. The dissection allowed us to appreciate the topographical organization of the white matter of the temporal lobe identifying the most important association, projection, and commissural fasciculi. The dissection from the lateral side allowed the progressive visualization of the superior longitudinal fasciculus and its components, the extreme and external capsule, the uncinate fasciculus, the inferior fronto-occipital fasciculus, the anterior commissure, the internal capsule, and the optic radiations. The dissection was completed from the inferior and medial side for identification of the cingulum and the fornix. The complex 3-dimensional organization of the white matter substance of the temporal lobe is characterized by 2 main systems of boundaries: the sagittal stratum and the temporal stem. Their knowledge is essential for the appropriate treatment of pathologies localized in this region as demonstrated by the 2 clinical cases presented in this work. Copyright © 2017 Elsevier Inc. All rights reserved.
Arterial changes in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) in relation to pathogenesis of diffuse myelin loss of cerebral white matter: examination of cerebral medullary arteries by reconstruction of serial sections of an autopsy case.
Okeda, Riki; Arima, Kunimasa; Kawai, Mitsuru
There is little information regarding the pathogenesis underlying diffuse myelin loss in the cerebral white matter and sparing of the U fibers in cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), in which the medial smooth muscle cells of systemic arteries are characteristically involved. We sought to examine the precise extent and severity of changes in the cerebral arteries in an autopsy case of CADASIL in relation to pathogenesis of the diffuse myelin loss. We reconstructed 1000 serial sections of the frontal cerebral medullary arteries of an autopsy subject, which was the first identified Japanese case of CADASIL, as confirmed by the presence of ultrastructural deposits of granular osmiophilic material in the media of some visceral arteries and by genetic analysis. We reconstructed 11 medullary arteries of the frontal lobe showing diffuse myelin loss and atrophy of the white matter with sparing of the U fibers. All of these showed complete loss of medial smooth muscle cells over their entire length and severe adventitial fibrosis. Although intimal fibrosis or hyalinosis was present, luminal occlusion was scarce. These changes were also observed in the small and large arachnoidal arteries but were relatively mild in the latter and in the cortical and subcortical medullary arteries. These arterial changes resulted in transformation of the cerebral arteries, in particular almost all the medullary arteries, to a so-called earthen pipe state. This supports the reported findings of a reduction in vascular reactivity to fluctuations in CO2 levels and systemic blood pressure in CADASIL.
Ökten, Ali İhsan
Myths are the keystone of mythology. They are interpretations of events that have been told as stories and legends for thousands of years, inherited from generation to generation, and have reached the present day. Although most myths are considered figments of the imagination or fictitious legends, all of them contain references to facts from the time they occurred. Mythology, which is a collection of figments of imagination concerning nature and human beings, is a product of human effort to perceive, explain, and interpret the universe and the world, much like science. The interaction between mythology and science dates back to the early days of civilization. Mythology, a reflection of human creativity, is extensively used in modern science, particularly in a terminological context. This article aims to reveal the texture of mythology in neurosurgery, by analyzing the birth of medicine in mythology; heroes such as Apollo and Asklepios, the gods of healing and medicine, as well as Hygieia, the goddess of health and hygiene; and mythological terms and phrases such as Achilles tendon, atlas vertebra, gigantism, priapism syndrome, hippocampus, lethargy, syrinx, and arachnoid. Through the use of symbols, mythology has attempted to explain several subjects, such as human nature, disease, birth, and death. In this respect, mythology and medicine dance arm in arm, and this dance has been going on for centuries. As a result, mythology has manifested itself in many fields within medicine, either anatomically or by giving names to various diseases. Copyright © 2016 Elsevier Inc. All rights reserved.
General Principles for Pial Synangiosis in Pediatric Moyamoya Patients: 2-Dimensional Operative Video.
Penn, David L; Wu, Kyle C; Presswood, Kayla R; Riordan, Coleman P; Scott, R Michael; Smith, Edward R
Pial synangiosis is a method of indirect surgical revascularization developed at our institution for the treatment of moyamoya disease in pediatric patients. Similar surgical principles are employed in adult cases, often performed because of lack of an adequate donor vessel. Standardized protocols, including preadmission for preoperative intravenous hydration and aspirin administration, as well as intraoperative electroencephalography, are routinely employed to minimize operative risk. Perioperative heparinization is not required. The patient is positioned supine, without skull fixation, and the parietal branch of the superficial temporal artery is mapped with Doppler ultrasonography. The artery is microscopically dissected from distal to proximal, leaving a cuff of tissue around the vessel and elevated from the temporalis. The microscope is then removed, the temporalis is opened in a cruciate fashion, and a generous craniotomy is performed, with care to drill away from the exposed artery. The dura is then opened widely (preserving dural collateral vessels), followed by microscopic opening of the arachnoid in as many areas as possible. The donor vessel is then sutured to the pia with 10-0 nylons. The dural leaflets are laid on the brain (without suturing). Closure is completed with saline-soaked gelfoam, with fixation of the bone flap, and muscle reapproximation in the horizontal plane. The galea is closed, followed by the use of resorbable skin suture in pediatric patients. If indicated, the second hemisphere may be performed under the same anesthetic, reducing anesthetic risks and avoiding delayed revascularization. Postoperatively, the patient is awakened and transferred to the intensive care unit.
Superficial subarachnoid cerebrospinal fluid space expansion after surgical drainage of chronic subdural hematoma.
Tosaka, Masahiko; Tsushima, Yoshito; Watanabe, Saiko; Sakamoto, Kazuya; Yodonawa, Masahiko; Kunimine, Hideo; Fujita, Haruyasu; Fujii, Takashi
The present study examined the computed tomography (CT) findings after surgery and overnight drainage for chronic subdural hematoma (CSDH) to clear the significance of inner superficial subarachnoid CSF space and outer subdural hematoma cavity between the brain surface and the inner skull. A total of 73 sides in 60 patients were evaluated. Head CT was performed on the day after surgery and overnight drainage (1st CT), within 3 weeks of surgery (2nd CT), and more than 3 weeks after surgery (3rd CT). Subdural and subarachnoid spaces were identified to focus on density of fluid, shape of air collection, and location of silicone drainage tube, etc. Cases with subdural space larger than the subarachnoid CSF space were classified as Group SD between the brain and the skull. Cases with subarachnoid CSF space larger than the subdural space were classified as Group SA. Cases with extremely thin (<3 mm) spaces between the brain and the skull were classified as Group NS. Group SA, SD, and NS accounted for 31.9, 55.6 and 12.5% of cases on the 1st CT. No statistical differences were found between Groups SA, SD, and NS in any clinical factors, including recurrence. Group SA were found significantly more on 1st CT than on 2nd and 3rd CT. Subarachnoid CSF space sometimes expands between the brain and skull on CT after surgical overnight drainage. Expansion of the arachnoid space may be a passive phenomenon induced by overnight drainage and delayed re-expansion of the brain parenchyma.
Recombinant canine distemper virus strain Snyder Hill expressing green or red fluorescent proteins causes meningoencephalitis in the ferret.
Ludlow, M; Nguyen, D T; Silin, D; Lyubomska, O; de Vries, R D; von Messling, V; McQuaid, S; De Swart, R L; Duprex, W P
The propensity of canine distemper virus (CDV) to spread to the central nervous system is one of the primary features of distemper. Therefore, we developed a reverse genetics system based on the neurovirulent Snyder Hill (SH) strain of CDV (CDV(SH)) and show that this virus rapidly circumvents the blood-brain and blood-cerebrospinal fluid (CSF) barriers to spread into the subarachnoid space to induce dramatic viral meningoencephalitis. The use of recombinant CDV(SH) (rCDV(SH)) expressing enhanced green fluorescent protein (EGFP) or red fluorescent protein (dTomato) facilitated the sensitive pathological assessment of routes of virus spread in vivo. Infection of ferrets with these viruses led to the full spectrum of clinical signs typically associated with distemper in dogs during a rapid, fatal disease course of approximately 2 weeks. Comparison with the ferret-adapted CDV(5804P) and the prototypic wild-type CDV(R252) showed that hematogenous infection of the choroid plexus is not a significant route of virus spread into the CSF. Instead, viral spread into the subarachnoid space in rCDV(SH)-infected animals was triggered by infection of vascular endothelial cells and the hematogenous spread of virus-infected leukocytes from meningeal blood vessels into the subarachnoid space. This resulted in widespread infection of cells of the pia and arachnoid mater of the leptomeninges over large areas of the cerebral hemispheres. The ability to sensitively assess the in vivo spread of a neurovirulent strain of CDV provides a novel model system to study the mechanisms of virus spread into the CSF and the pathogenesis of acute viral meningitis.
Avoidance of postoperative epistaxis and anosmia in endonasal endoscopic skull base surgery: a technical note.
Griffiths, Chester F; Cutler, Aaron R; Duong, Huy T; Bardo, Gal; Karimi, Kian; Barkhoudarian, Garni; Carrau, Ricardo; Kelly, Daniel F
Most endoscopic transsphenoidal approaches jeopardize the sphenopalatine artery and septal olfactory strip (SOS), increasing the risk of postoperative anosmia and epistaxis while precluding the ability to raise pedicled nasoseptal flaps (NSF). We describe a bilateral "rescue flap" technique that preserves the mucosa containing the nasal-septal vascular pedicles and the SOS. This approach can reduce the risk of postoperative complications, including epistaxis and anosmia. A retrospective analysis was conducted of all patients who underwent endoscopic transsphenoidal surgery with preservation of both sphenopalatine vascular pedicles and SOS. In a recent subset of patients, olfactory assessment was performed. Of 174 consecutive operations performed in 161 patients, bilateral preservation of the sphenopalatine vascular pedicle and SOS was achieved in 139 (80 %) operations, including 31 (22 %) with prior transsphenoidal surgery. Of the remaining 35 operations, 18 had a planned formal NSF and 17 had prior surgery or extensive lesions precluding use of this technique. Of pituitary adenomas, RCCs or sellar arachnoid cysts, 118 (94 %) underwent this approach, including 91 % of patients who had prior surgery. Preoperative olfaction function was maintained in 97 % of patients that were tested. None of the patients had postoperative arterial epistaxis. Preservation of bilateral sphenopalatine vascular pedicles and the SOS is feasible in over 90 % of patients undergoing endonasal endoscopic surgery for pituitary adenomas and RCCs. This approach, while not hindering exposure or limiting instrument maneuverability, preserves the nasoseptal vasculature for future NSF use if needed and appears to minimize the risks of postoperative arterial epistaxis and anosmia.
Ultrastructure of canine meninges after repeated epidural injection of S(+)-ketamine.
Acosta, Alinne; Gomar, Carmen; Bombí, Josep A; Graça, Dominguita L; Garrido, Marta; Krauspenhar, Cristina
The safety of ketamine when administered by the spinal route must be confirmed in various animal species before it is approved for use in humans. This study evaluates the ultrastructure of canine meninges after repeated doses of epidural S(+)-ketamine. Five dogs received S(+)-ketamine 5%, 1 mg/kg, twice a day for 10 days through an epidural catheter with its tip located at the L5 level. One dog received the same volume of normal saline at the same times. The spinal cord and meninges were processed for histopathological and ultrastructural studies. Clinical effects were assessed after each injection. Motor and sensory block appeared after each injection of S(+)-ketamine, but not in the dog receiving saline. No signs of clinical or neurologic alterations were observed. Using light microscopy, no meningeal layer showed alterations except focal infiltration at the catheter tip level by macrophages, lymphocytes, and a few mast cells. The cells of different layers were studied by electron microscopy and interpreted according to data from human and other animal species because no ultrastructural description of the canine meninges is currently available. There were no cellular signs of inflammation, phagocytosis, or degeneration in meningeal layers and no signs of atrophy, compression, or demyelinization in the areas of dorsal root ganglia and spinal cord around the arachnoid. These findings were common for dogs receiving S(+)-ketamine and the dog receiving saline. Repeated doses of epidural S(+)-ketamine 5%, 1 mg/kg, twice a day for 10 days was not associated to cellular alterations in canine meninges.
Acquired Chiari Malformation and Syringomyelia Secondary to Space-Occupying Lesions: A Systematic Review.
Wang, Justin; Alotaibi, Naif M; Samuel, Nardin; Ibrahim, George M; Fallah, Aria; Cusimano, Michael D
Acquired Chiari malformations (ACM) and associated syringomyelia secondary to space-occupying lesions can cause neurologic deficits independent of or in combination with the offending mass. Although type I Chiari malformations are traditionally treated with posterior fossa decompression, optimal surgical management of ACM and associated syringomyelia remains unclear. The purpose of this study is to review the current literature surrounding the management of ACM. A systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Using the relevant keywords, articles were identified through multiple databases from inception to April 2016. Our primary outcome was postoperative resolution of tonsillar herniation, syringomyelia, and clinical symptoms and signs. Thirty studies (27 case reports and 3 case series), encompassing 44 patients, were included in the review. Meningiomas (36%) and arachnoid cysts (32%) were the lesions most commonly associated with ACM. Offending lesions were usually large (85%) and almost all were found in the posterior fossa (89%). Syringomyelia was present in 82% of cases. Overall, all but 1 patient had improvement or resolution of their syringomyelia after surgery and none required a syrinx shunt. Rates of tonsillar ascent, syrinx resolution, and neurologic recovery were similar in patients who underwent lesion removal alone versus those who underwent posterior fossa decompression and lesion removal. Space-occupying lesions in the posterior fossa are a rare cause of ACM and syringomyelia. Surgical management of the underlying lesion improves ACM and associated syringomyelia without the need for syrinx shunting. Copyright © 2016 Elsevier Inc. All rights reserved.
Theoretical considerations on the pathophysiology of normal pressure hydrocephalus (NPH) and NPH-related dementia.
Hamlat, Abderrahmane; Adn, Mahmoudreza; Sid-ahmed, Seddik; Askar, Brahim; Pasqualini, Edouardo
Normal pressure hydrocephalus (NPH) is considered to be an example of reversible dementia although clinical improvement after shunting varies from subject to subject, and recent studies have pointed to a possible link with other dementia. The authors consider that the craniospinal compartment is a partially closed sphere with control device systems represented by the spinal axis and the sagittal sinus-arachnoid villi complex which interact with each other in the clinical patient setting. We hypothesise that changing spinal compliance by altering the flow process and CSF dynamics lead to hydrocephalus. Therefore four NPH types have been distinguished according to the alterations in spinal compliance, decrease in CSF absorption at the sagittal sinus or both occurrences. The authors consider that NPH and NPH-related diseases (NPH-RD) are initiated by the same common final pathway and demonstrate that NPH could represent an initial stage of NPH-RD. Progression of clinical signs can be explained as damage to the cerebral tissue by both intermittent increased intracranial pressure and pulse pressure waves leading to periventricular ischaemia. In addition, they believe that both volume equilibrium and spinal compliance are restored in patients who improve after CSF shunt, whereas in patients whose condition does not improve, only volume equilibrium is restored and not spinal compliance, which was the underlying cause of hydrocephalus in such cases. They therefore wonder whether cervical decompression should not be indicated in patients who show no improvement. Although attractive, this analysis warrants confirmation from clinical, radiological, and hydrodynamic studies.
Repair of Frontoethmoidal Encephalocele in the Philippines: An Account of 30 Cases Between 2008-2013.
Marshall, Amanda-Lynn; Setty, Pradeep; Hnatiuk, Mark; Pieper, Daniel R
Frontoethmoidal encephalocele is a congenital abnormality of the anterior skull base involving herniation of cranial contents through a midline skull defect. Patency of the foramen cecum, along with other multifactorial variables, contributes to the development of frontoethmoidal encephaloceles. Because of limited resources, financial constraints, and lack of surgical expertise, repair of frontoethmoidal encephaloceles is limited in developing countries. Between 2008 and 2013 an interdisciplinary team composed of neurosurgeons, craniofacial surgeons, otolaryngologists, plastic surgeons, and nursing personnel, conducted surgical mission trips to Davao City in Mindanao, Philippines. All patients underwent a combined extracranial/intracranial surgical approach, performed in tandem by a neurosurgeon and a craniofacial surgeon, to detach and remove the encephalocele. This procedure was followed by reconstruction of the craniofacial defects. A total of 30 cases of frontoethmoidal encephalocele were repaired between 2008 and 2013 (20 male; 10 female). The average age at operation was 8.7 years, with 7 patients older than 17 years. Of the 3 subtypes, the following breakdown was observed in patients: 18 nasoethmoidal; 9 nasofrontal; and 3 naso-orbital. Several patients showed concurrent including enlarged ventricles, arachnoid cysts (both unilateral and bilateral), and gliotic changes, as well as orbit and bulbus oculi (globe) deformities. There were no operative-associated mortalities or neurologic deficits, infections, or hydrocephalus on follow-up during subsequent trips. Despite the limitations of performing advanced surgery in a developing country, the combined interdisciplinary surgical approach has offered effective treatment to improve physical appearance and psychological well-being in afflicted patients. Copyright © 2017 Elsevier Inc. All rights reserved.
Recombinant Canine Distemper Virus Strain Snyder Hill Expressing Green or Red Fluorescent Proteins Causes Meningoencephalitis in the Ferret
Ludlow, M.; Nguyen, D. T.; Silin, D.; Lyubomska, O.; de Vries, R. D.; von Messling, V.; McQuaid, S.; De Swart, R. L.
The propensity of canine distemper virus (CDV) to spread to the central nervous system is one of the primary features of distemper. Therefore, we developed a reverse genetics system based on the neurovirulent Snyder Hill (SH) strain of CDV (CDVSH) and show that this virus rapidly circumvents the blood-brain and blood-cerebrospinal fluid (CSF) barriers to spread into the subarachnoid space to induce dramatic viral meningoencephalitis. The use of recombinant CDVSH (rCDVSH) expressing enhanced green fluorescent protein (EGFP) or red fluorescent protein (dTomato) facilitated the sensitive pathological assessment of routes of virus spread in vivo. Infection of ferrets with these viruses led to the full spectrum of clinical signs typically associated with distemper in dogs during a rapid, fatal disease course of approximately 2 weeks. Comparison with the ferret-adapted CDV5804P and the prototypic wild-type CDVR252 showed that hematogenous infection of the choroid plexus is not a significant route of virus spread into the CSF. Instead, viral spread into the subarachnoid space in rCDVSH-infected animals was triggered by infection of vascular endothelial cells and the hematogenous spread of virus-infected leukocytes from meningeal blood vessels into the subarachnoid space. This resulted in widespread infection of cells of the pia and arachnoid mater of the leptomeninges over large areas of the cerebral hemispheres. The ability to sensitively assess the in vivo spread of a neurovirulent strain of CDV provides a novel model system to study the mechanisms of virus spread into the CSF and the pathogenesis of acute viral meningitis. PMID:22553334
Diffuse leptomeningeal neuroepithelial tumor: 9 pediatric cases with chromosome 1p/19q deletion status and IDH1 (R132H) immunohistochemistry.
Schniederjan, Matthew J; Alghamdi, Sarah; Castellano-Sanchez, Amilcar; Mazewski, Claire; Brahma, Barunashish; Brat, Daniel J; Brathwaite, Carole D; Janss, Anna J
Leptomeningeal dissemination in children is typical of high-grade, and occasionally low-grade, neoplasms. Rare cases of widely disseminated oligodendroglia-like leptomeningeal tumors, sometimes with associated spinal cord lesions, have been described that respond to treatment and follow an indolent course. Whether these lesions represent an established tumor category or are a unique entity remains to be established. We present 9 pediatric cases of such diffuse leptomeningeal neuroepithelial tumors (DLNT), 8 with assessment of 2 common genetic alterations seen in oligodendrogliomas, 1p and 19q chromosomal deletions and isocitrate dehydrogenase-1 (IDH1) R132H mutations. Four patients were male and 5 female, with a mean age at presentation of 4 years (range, 2 to 7 y). All presented with signs of increased intracranial pressure and diffuse contrast enhancement of the leptomeninges by magnetic resonance imaging. Three had a cervical or upper thoracic spinal cord tumor, and another had a small cerebellar lesion. Leptomeningeal biopsies showed a thickened and fibrotic arachnoid infiltrated by monotonous cells with round nuclei and prominent perinuclear clearing. All cases were strongly immunoreactive for S100 protein, and most showed faint granular synaptophysin reactivity. Six of 8 cases showed deletions of chromosome arm 1p by fluorescence in situ hybridization, 2 of which also had loss of 19q. None of the lesions reacted with IDH1-R132H antibodies. Although the clinicopathologic features show overlap of these DLNT lesions with oligodendroglioma and extraventricular neurocytoma, they do not exactly match either one, suggesting that DLNTs are a distinct tumor entity.
Sporadic periventricular nodular heterotopia: Classification, phenotype and correlation with Filamin A mutations.
Liu, Wenyu; Yan, Bo; An, Dongmei; Xiao, Jiahe; Hu, Fayun; Zhou, Dong
The purpose of this study was to better delineate the clinical spectrum of periventricular nodular heterotopia (PNH) in a large patient population after long term follow up. Specifically, this study aimed to relate PNH subtypes to clinical or epileptic outcomes, epileptic discharges and underlying Filamin A (FLNA) mutations by analyzing anatomical features. The study included 100 patients with radiologically confirmed nodular heterotopia. Patients' FLNA gene sequences and medical records were analyzed. Two-sided Chi-square test and Fisher's exact t-test were used to assess associations between the distribution of PNHs and specific clinical features. Based on imaging data, patients were subdivided into three groups: (a) classical (bilateral frontal and body, n=41 patients), (b) bilateral asymmetrical or posterior (n=16) and (c) unilateral heterotopia (n=43). Most patients with classical heterotopia were females (P=0.033) and were likely to have arachnoid cysts (P=0.025) and cardiac abnormalities (P=0.041), but were mostly seizure-free. Additionally, hippocampal abnormalities (P=0.022), neurological deficits (P=0.028) and cerebellar abnormalities (P=0.005) were more common in patients with bilateral asymmetrical heterotopia. Patients with unilateral heterotopia were prone to develop refractory epilepsy (P=0.041). FLNA mutations were identified in 8 patients. Each group's distinctive genetic mutations, epileptic discharge patterns and overall clinical outcomes confirm that the proposed classification system is reliable. These findings could not only be an indicator of a more severe morphological and clinical phenotype, but could also have clinical implications with respect to the epilepsy management and optimization of therapeutic options. Copyright © 2017 Elsevier B.V. All rights reserved.
External Ventricular Drain and Hemorrhage in Aneurysmal Subarachnoid Hemorrhage Patients on Dual Antiplatelet Therapy: A Retrospective Cohort Study.
Hudson, Joseph S; Prout, Benjamin S; Nagahama, Yasunori; Nakagawa, Daichi; Guerrero, Waldo R; Zanaty, Mario; Chalouhi, Nohra; Jabbour, Pascal; Dandapat, Sudeepta; Allan, Lauren; Ortega-Gutierrez, Santiago; Samaniego, Edgar A; Hasan, David
Stenting and flow diversion for aneurysmal sub arachnoid hemorrhage (aSAH) require the use of dual antiplatelet therapy (DAPT). To investigate whether DAPT is associated with hemorrhagic complication following placement of external ventricular drains (EVD) in patients with aSAH. Rates of radiographically identified hemorrhage associated with EVD placement were compared between patients who received DAPT for stenting or flow diversion, and patients who underwent microsurgical clipping or coiling and did not receive DAPT by way of a backward stepwise multivariate analysis. Four hundred forty-three patients were admitted for aSAH management. Two hundred ninety-eight patients required placement of an EVD. One hundred twenty patients (40%) were treated with stent-assisted coiling or flow diversion and required DAPT, while 178 patients (60%) were treated with coiling without stents or microsurgical clipping and did not receive DAPT. Forty-two (14%) cases of new hemorrhage along the EVD catheter were identified radiographically. Thirty-two of these hemorrhages occurred in patients on DAPT, while 10 occurred in patients without DAPT. After multivariate analysis, DAPT was significantly associated with radiographic hemorrhage [odds ratio: 4.92, 95% confidence interval: 2.45-9.91, P = .0001]. We did not observe an increased proportion of symptomatic hemorrhage in patients receiving DAPT (10 of 32 [31%]) vs those without (5 of 10 [50%]; P = .4508). Patients with aSAH who receive stent-assisted coiling or flow diversion are at higher risk for radiographic hemorrhage associated with EVD placement. The timing between EVD placement and DAPT initiation does not appear to be of clinical significance. Stenting and flow diversion remain viable options for aSAH patients.
Prevention of intraoperative cerebrospinal fluid leaks by lumbar cerebrospinal fluid drainage during surgery for pituitary macroadenomas.
Mehta, Gautam U; Oldfield, Edward H
Cerebrospinal fluid leakage is a major complication of transsphenoidal surgery. An intraoperative CSF leak, which occurs in up to 50% of pituitary tumor cases, is the only modifiable risk factor for postoperative leaks. Although several techniques have been described for surgical repair when an intraoperative leak is noted, none has been proposed to prevent an intraoperative CSF leak. The authors postulated that intraoperative CSF drainage would diminish tension on the arachnoid, decrease the rate of intraoperative CSF leakage during surgery for larger tumors, and reduce the need for surgical repair of CSF leaks. The results of 114 transsphenoidal operations for pituitary macroadenoma performed without intraoperative CSF drainage were compared with the findings from 44 cases in which a lumbar subarachnoid catheter was placed before surgery to drain CSF at the time of dural exposure and tumor removal. Cerebrospinal fluid drainage reduced the rate of intraoperative CSF leakage from 41% to 5% (p < 0.001). This reduction occurred in macroadenomas with (from 57% to 5%, p < 0.001) and those without suprasellar extension (from 29% to 0%, p = 0.31). The rate of postoperative CSF leakage was similar (5% vs 5%), despite the fact that intraoperative CSF drainage reduced the need for operative repair (from 32% to 5%, p < 0.001). There were no significant catheter-related complications. Cerebrospinal fluid drainage during transsphenoidal surgery for macroadenomas reduces the rate of intraoperative CSF leaks. This preventative measure obviated the need for surgical repair of intraoperative CSF leaks using autologous fat graft placement, other operative techniques, postoperative lumbar drainage, and/or reoperation in most patients and is associated with minimal risks.
Preliminary Stratigraphic Basis for Geologic Mapping of Venus
NASA Technical Reports Server (NTRS)
Basilevsky, A. T.; Head, J. W.
The age relations between geologic formations have been studied at 36 1000x1000 km areas centered at the dark paraboloid craters. The geologic setting in all these sites could be characterized using only 16 types of features and terrains (units). These units form a basic stratigraphic sequence (from older to younger: (1) Tessera (Tt); (2-3) Densely fractured terrains associated with coronae (COdf) and in the form of remnants among plains (Pdf); (4) Fractured and ridged plains (Pfr); (5) Plains with wrinkle ridges (Pwr); (6-7) Smooth and lobate plains (Ps/Pl); and (8) Rift-associated fractures (Fra). The stratigraphic position of the other units is determined by their relation with the units of the basic sequence: (9) Ridge bells (RB), contemporary with Pfr; (10-11) Ridges of coronae and arachnoids annuli (COar/Aar), contemporary with wrinkle ridges of Pwr; (12) Fractures of coronae annuli (COaf) disrupt Pwr and Ps/Pl; (13) Fractures (F) disrupt Pwr or younger units; (14) Craters with associated dark paraboloids (Cdp), which are on top of all volcanic and tectonic units except the youngest episodes of rift-associated fracturing and volcanism; (15-16) Surficial streaks (Ss) and surficial patches (Sp) are approximately contemporary with Cdp. These units may be used as a tentative basis for the geologic mapping of Venus including VMAP. This mapping should test the stratigraphy and answer the question of whether this stratigraphic sequence corresponds to geologic events which were generally synchronous all around the planet or whether the sequence is simply a typical sequence of events which occurred in different places at diffferent times.
Spontaneous nasal cerebrospinal fluid leaks and empty sella syndrome: a clinical association.
Schlosser, Rodney J; Bolger, William E
Spontaneous, idiopathic nasal meningoencephaloceles are herniations of arachnoid/dura and cerebrospinal fluid (CSF) through anatomically fragile sites within the skull base. Empty sella syndrome occurs when intracranial contents herniate through the sellar diaphragm filling the sella turcica with CSF and giving the radiographic appearance of an absent pituitary gland. The objective of this study was to examine the association between spontaneous encephaloceles/CSF leaks and empty sella syndrome because of their similar clinical features and potential common pathophysiology. Retrospective. Sixteen patients were treated for spontaneous encephaloceles between 1996 and 2001. All 16 patients had associated CSF leaks. Five patients had multiple simultaneous encephaloceles. Fifteen patients with imaging of the sella turcica had empty (10 patients) or partially empty (5 patients) sellas. One patient did not have complete imaging of the sella. Three patients had lumbar punctures with measurement of CSF pressure during computed tomography cisternograms because of multiple skull base defects. Mean CSF pressure was 28.3 cm of water (range, 19-34 cm; normal, 0-15 cm). Thirteen of 16 patients (81%) were obese women (mean body mass index 35.9 kg/m2; normal, <25 kg/m2). Mean follow-up was 14.2 months with 100% success in closure of the defects after one procedure. Spontaneous meningoencephaloceles and CSF leaks are strongly associated with radiographic findings of an empty sella and suggest a common pathophysiology. The underlying condition probably represents a form of intracranial hypertension that exerts hydrostatic pressure at anatomically weakened sites within the skull base. Otolaryngologists should be familiar with this disease entity and the implications intracranial hypertension has on patient management.
Stroke in tuberculous meningitis.
Misra, Usha Kant; Kalita, Jayantee; Maurya, Pradeep Kumar
Stroke in tuberculous meningitis (TBM) occurs in 15-57% of patients especially in advance stage and severe illness. The majority of strokes may be asymptomatic because of being in a silent area, deep coma or associated pathology such as spinal arachnoiditis or tuberculoma. Methods of evaluation also influence the frequency of stroke. MRI is more sensitive in detecting acute (DWI) and chronic (T2, FLAIR) stroke. Most of the strokes in TBM are multiple, bilateral and located in the basal ganglia especially the 'tubercular zone' which comprises of the caudate, anterior thalamus, anterior limb and genu of the internal capsule. These are attributed to the involvement of medial striate, thalamotuberal and thalamostriate arteries which are embedded in exudates and likely to be stretched by a coexistent hydrocephalus. Cortical stroke can also occur due to the involvement of proximal portion of the middle, anterior and posterior cerebral arteries as well as the supraclinoid portion of the internal carotid and basilar arteries which are documented in MRI, angiography and autopsy studies. Arteritis is more common than infarction in autopsy study. The role of cytokines especially tumor necrosis factor (TNFα), vascular endothelial growth factor (VEGF) and matrix metaloproteineases (MMPs) in damaging the blood brain barrier, attracting leucocytes and release of vasoactive autocoids have been suggested. The prothrombotic state may also contribute to stroke in TBM. Corticosteroids with antitubercular therapy were thought to reduce mortality and morbidity but their role in reducing strokes has not been proven. Aspirin also reduces mortality and its role in reducing stroke in TBM needs further studies. Copyright © 2010 Elsevier B.V. All rights reserved.
Humphrey Ridley (1653-1708): 17th century evolution in neuroanatomy and selective cerebrovascular injections for cadaver dissection.
Thakur, Jai Deep; Sonig, Ashish; Chittiboina, Prashant; Khan, Imad Saeed; Wadhwa, Rishi; Nanda, Anil
Humphrey Ridley, M.D. (1653-1708), is a relatively unknown historical figure, belonging to the postmedieval era of neuroanatomical discovery. He was born in the market town of Mansfield, 14 miles from the county of Nottinghamshire, England. After studying at Merton College, Oxford, he pursued medicine at Leiden University in the Netherlands. In 1688, he was incorporated as an M.D. at Cambridge. Ridley authored the first original treatise in English language on neuroanatomy, The Anatomy of the Brain Containing its Mechanisms and Physiology: Together with Some New Discoveries and Corrections of Ancient and Modern Authors upon that Subject. Ridley described the venous anatomy of the eponymous circular sinus in connection with the parasellar compartment. His methods were novel, unique, and effective. To appreciate the venous anatomy, he preferred to perform his anatomical dissections on recently executed criminals who had been hanged. These cadavers had considerable venous engorgement, which made the skull base venous anatomy clearer. To enhance the appearance of the cerebral vasculature further, he used tinged wax and quicksilver in the injections. He set up experimental models to answer questions definitively, in proving that the arachnoid mater is a separate meningeal layer. The first description of the subarachnoid cisterns, blood-brain barrier, and the fifth cranial nerve ganglion with its branches are also attributed to Ridley. This historical vignette revisits Ridley's life and academic work that influenced neuroscience and neurosurgical understanding in its infancy. It is unfortunate that most of his novel contributions have gone unnoticed and uncited. The authors hope that this article will inform the neurosurgical community of Ridley's contributions to the field of neurosurgery.
Neural system antigens are recognized by autoantibodies from patients affected by a new variant of endemic pemphigus foliaceus in Colombia.
Abreu-Velez, Ana Maria; Howard, Michael S; Yi, Hong; Gao, Weiqing; Hashimoto, Takashi; Grossniklaus, Hans E
Endemic pemphigus foliaceus (EPF), is also known as "fogo selvagem" or "wild fire," reflecting the intense burning sensation of the skin reported by patients with this disease. Based on this finding, we tested for neural autoreactivity in patients affected by a new variant of EPF (El Bagre-EPF). We tested 20 El Bagre-EPF patients, 20 normal controls from the endemic area, and 20 age- and sex-matched normal controls from outside the endemic area. We tested for autoreactivity to several immunoglobulins and complement. Both human skin and bovine tail were used as antigens. We detected autoreactivity to neural structures, mechanoreceptors, nerves, perineural cell layers of the arachnoid envelope around the optic nerve, brain structures, and to neuromuscular spindles; these structures colocalized with several neural markers. The patient antibodies also colocalized with desmoplakins 1 and 2, with the armadillo repeat protein deleted in velo-cardio-facial syndrome and with p0071 antibodies. Autoreactivity was also found associated with neurovascular bundles innervating the skin, and immunoelectron microscopy using protein A gold against patient antibodies was positive against the nerve axons. Paucicellularity of the intraepidermal nerve endings and defragmentation of the neural plexus were seen in 70% of the cases and not in the controls from the endemic area (p<0.005). Neuropsychological and/or behavioral symptoms were detected in individuals from the endemic area, including sensorimotor axonal neuropathy. Our findings may explain for the first time the "pose of pemphigus," representing a dorsiflexural posture seen in EPF patients vis-a-vis the weakness of the extensor nerves, and furthermore, the autoreactivity to nerves in EPF could explain the "burning sensation" encountered in EPF disease.
Brain magnetic resonance imaging findings in Smith-Lemli-Opitz syndrome.
Lee, Ryan W Y; Conley, Sandra K; Gropman, Andrea; Porter, Forbes D; Baker, Eva H
Smith-Lemli-Opitz syndrome (SLOS) is a neurodevelopmental disorder caused by inborn errors of cholesterol metabolism resulting from mutations in 7-dehydrocholesterol reductase (DHCR7). There are only a few studies describing the brain imaging findings in SLOS. This study examines the prevalence of magnetic resonance imaging (MRI) abnormalities in the largest cohort of patients with SLOS to date. Fifty-five individuals with SLOS (27 M, 28 F) between age 0.17 years and 25.4 years (mean = 6.2, SD = 5.8) received a total of 173 brain MRI scans (mean = 3.1 per subject) on a 1.5T GE scanner between September 1998 and December 2003, or on a 3T Philips scanner between October 2010 and September 2012; all exams were performed at the Clinical Center of the National Institutes of Health. We performed a retrospective review of these imaging studies for both major and minor brain anomalies. Aberrant MRI findings were observed in 53 of 55 (96%) SLOS patients, with abnormalities of the septum pellucidum the most frequent (42/55, 76%) finding. Abnormalities of the corpus callosum were found in 38 of 55 (69%) patients. Other findings included cerebral atrophy, cerebellar atrophy, colpocephaly, white matter lesions, arachnoid cysts, Dandy-Walker variant, and type I Chiari malformation. Significant correlations were observed when comparing MRI findings with sterol levels and somatic malformations. Individuals with SLOS commonly have anomalies involving the midline and para-midline structures of the brain. Further studies are required to examine the relationship between structural brain abnormalities and neurodevelopmental disability in SLOS. © 2013 The Authors. American Journal of Medical Genetics Part A Published by U.S. Government Work.
Microsurgical Resection of Suprasellar Craniopharyngioma-Technical Purview.
Nanda, Anil; Narayan, Vinayak; Mohammed, Nasser; Savardekar, Amey R; Patra, Devi Prasad
Objectives Complete surgical resection is an important prognostic factor for recurrence and is the best management for craniopharyngioma. This operative video demonstrates the technical nuances in achieving complete resection of a suprasellar craniopharyngioma. Design and Setting The surgery was performed in a middle-aged lady who presented with the history of progressive bitemporal hemianopia and excessive sleepiness over 8 months. On imaging, suprasellar craniopharyngioma was identified. The tumor was approached through opticocarotid cistern and lamina terminalis. Exposure of bilateral optic nerves, right internal carotid artery, anterior cerebral artery, and its perforator branches was then afforded and the tumor was gross totally resected. Results The author demonstrates step-by-step technique of microsurgical resection of suprasellar craniopharyngioma. The narrow corridor to deeper structures, intricacies of multiple perforator vessels, and the technique of arachnoid and capsule dissection are the main challenging factors for the gross total resection of craniopharyngioma. The tumor portion which lies under the ipsilateral optic nerve is a blind spot region with a high chance of leaving residual tumor. Mobilization of optic nerve may endanger visual function too. The use of handheld mirror ['mirror-technique'] helps in better visualization of this blind spot and achieve complete excision. Conclusions The technical pearls of craniopharyngioma surgery include the optimum utilization of translamina terminalis route, wide opening of the cisterns, meticulous separation of deep perforator vessels, capsular mobilization/traction avoidance, and the use of "mirror-technique" for blind-spot visualization. These surgical strategies help to achieve complete resection without causing neurological deficit. The link to the video can be found at: https://youtu.be/9wHJ4AUpG50 .
Endoscopic Endonasal Resection of Retrochiasmatic Craniopharyngioma with Fascia Lata Button and Nasoseptal Flap Reconstruction.
Kshettry, Varun R; Nyquist, Gurston; Evans, James J
Surgery for craniopharyngiomas can be challenging due to the involvement of multiple critical neurovascular structures. The expanded endoscopic endonasal approach can provide superior access to suprasellar craniopharyngiomas, particularly with retrochiasmatic extension and significant hypothalamic involvement. We describe the surgical technique used to treat a 30-year-old patient who presented with 4 weeks of worsening vision, fatigue, and memory loss. His vision was counting fingers at 1 feet on the right and 20/800 on the left with a temporal hemianopsia. Laboratory evaluation demonstrated central hypoadrenalism, hypothyroidism, and hypogonadism. Imaging showed a large solid and cystic suprasellar mass. The transtubercular approach with removal of the lateral tubercular strut can provide wide bilateral access to the opticocarotid region. The superior intercavernous sinus must be coagulated and ligated. Initial arachnoid dissection is centered at the midline, mobilizing the superior hypophyseal branches to the optic apparatus laterally. The cyst capsule is opened and care is taken to minimize spillage of cyst fluid into the subarachnoid space. Central debulking and then extracapsular dissection is performed under direct visualization using sharp dissection. Reconstruction of the dura is performed with an inlay/onlay fascia lata button that is held together with four sutures that hold the graft edges against the native dural edges. This is followed by vascularized nasoseptal flap reconstruction. No lumbar drain or nonabsorbable packing is required. The patient's vision had dramatic improvement and by 1 week postoperatively was 20/20 with full visual fields. Postoperative diabetes insipidus was managed with nasal desmopressin. Postoperative MRI demonstrated complete removal. The link to the video can be found at: https://youtu.be/QQxCNUcq1qg .
Predictive Factors for Vision Recovery after Optic Nerve Decompression for Chronic Compressive Neuropathy: Systematic Review and Meta-Analysis
Carlson, Andrew P.; Stippler, Martina; Myers, Orrin
Objectives Surgical optic nerve decompression for chronic compressive neuropathy results in variable success of vision improvement. We sought to determine the effects of various factors using meta-analysis of available literature. Design Systematic review of MEDLINE databases for the period 1990 to 2010. Setting Academic research center. Participants Studies reporting patients with vision loss from chronic compressive neuropathy undergoing surgery. Main outcome measures Vision outcome reported by each study. Odds ratios (ORs) and 95% confidence intervals (CIs) for predictor variables were calculated. Overall odds ratios were then calculated for each factor, adjusting for inter study heterogeneity. Results Seventy-six studies were identified. Factors with a significant odds of improvement were: less severe vision loss (OR 2.31[95% CI = 1.76 to 3.04]), no disc atrophy (OR 2.60 [95% CI = 1.17 to 5.81]), smaller size (OR 1.82 [95% CI = 1.22 to 2.73]), primary tumor resection (not recurrent) (OR 3.08 [95% CI = 1.84 to 5.14]), no cavernous sinus extension (OR 1.88 [95% CI = 1.03 to 3.43]), soft consistency (OR 4.91 [95% CI = 2.27 to 10.63]), presence of arachnoid plane (OR 5.60 [95% CI = 2.08 to 15.07]), and more extensive resection (OR 0.61 [95% CI = 0.4 to 0.93]). Conclusions Ophthalmologic factors and factors directly related to the lesion are most important in determining vision outcome. The decision to perform optic nerve decompression for vision loss should be made based on careful examination of the patient and realistic discussion regarding the probability of improvement. PMID:24436885
Targeted deletion of RIC8A in mouse neural precursor cells interferes with the development of the brain, eyes, and muscles.
Kask, Keiu; Tikker, Laura; Ruisu, Katrin; Lulla, Sirje; Oja, Eva-Maria; Meier, Riho; Raid, Raivo; Velling, Teet; Tõnissoo, Tambet; Pooga, Margus
Autosomal recessive disorders such as Fukuyama congenital muscular dystrophy, Walker-Warburg syndrome, and the muscle-eye-brain disease are characterized by defects in the development of patient's brain, eyes, and skeletal muscles. These syndromes are accompanied by brain malformations like type II lissencephaly in the cerebral cortex with characteristic overmigrations of neurons through the breaches of the pial basement membrane. The signaling pathways activated by laminin receptors, dystroglycan and integrins, control the integrity of the basement membrane, and their malfunctioning may underlie the pathologies found in the rise of defects reminiscent of these syndromes. Similar defects in corticogenesis and neuromuscular disorders were found in mice when RIC8A was specifically removed from neural precursor cells. RIC8A regulates a subset of G-protein α subunits and in several model organisms, it has been reported to participate in the control of cell division, signaling, and migration. Here, we studied the role of RIC8A in the development of the brain, muscles, and eyes of the neural precursor-specific conditional Ric8a knockout mice. The absence of RIC8A severely affected the attachment and positioning of radial glial processes, Cajal-Retzius' cells, and the arachnoid trabeculae, and these mice displayed additional defects in the lens, skeletal muscles, and heart development. All the discovered defects might be linked to aberrancies in cell adhesion and migration, suggesting that RIC8A has a crucial role in the regulation of cell-extracellular matrix interactions and that its removal leads to the phenotype characteristic to type II lissencephaly-associated diseases. © 2018 Wiley Periodicals, Inc. Develop Neurobiol 78: 374-390, 2018. © 2018 Wiley Periodicals, Inc.
Histopathological study of the outer membrane of the dura mater in chronic sub dural hematoma: Its clinical and radiological correlation
Bokka, Sriharsha; Trivedi, Adarsh
Background: A chronic subdural hematoma is an old clot of blood on the surface of the brain between dura and arachnoid membranes. These liquefied clots most often occur in patients aged 60 and older with brain atrophy. When the brain shrinks inside the skull over time, minor head trauma can cause tearing of blood vessels over the brain surface, resulting in a slow accumulation of blood over several days to weeks. Aim of the Study: To evaluate the role of membrane in hematoma evaluation and to correlate its histopathology with clinic-radiological aspects of the condition and overall prognosis of patients. Material and Methods: The study incorporated all cases of chronic SDH admitted to the Neurosurgery department of JLN Hospital and Research Centre, Bhilai, between November 2011 and November 2013. All such cases were analyzed clinically, radiologically like site, size, thickness in computed tomography, the attenuation value, midline shift and histopathological features were recorded. Criteria for Inclusion: All cases of chronic subdural haematoma irrespective of age and sex were incorporated into the study. Criteria for Exclusion: All cases of acute subdural haematoma and cases of chronic sub dural hematoma which were managed conservatively irrespective of age and sex were excluded from the study Results: In our series of cases, the most common histopathological type of membrane was the inflammatory membrane (Type II) seen in 42.30% of cases followed by hemorrhagic inflammatory membrane (Type III) seen in 34.62% of cases while scar inflammatory type of membrane (Type IV) was seen in 23.08% of cases. No case with noninflammatory type (Type I) was encountered. PMID:26889276
[Hydrocephalus in childhood : causes and imaging patterns].
Pomschar, A; Koerte, I; Peraud, A; Heinen, F; Herber-Jonat, S; Reiser, M; Ertl-Wagner, B
Causes and imaging patterns of hydrocephalus differ depending on the age of the patient. Traditionally, hydrocephalus was classified into non-communicating and communicating hydrocephalus but more recent classifications also take the site of occlusion and the etiology into account. For the diagnostic work-up computed tomography (CT), sonography and magnetic resonance imaging (MRI) are available and MRI is the method of choice for children and adolescents as it allows determination of the cause and location of a possible obstruction. In the first 12-18 months sonography allows evaluation of the lateral ventricles and the third ventricle and CT is usually only chosen in children in emergency situations and/or if no other modality is available. We retrospectively evaluated a population of 785 children and adolescents (426 males aged 0-17 years) referred for MRI between April 2009 and March 2012 due to headaches, somnolence, concentration difficulties or developmental delay. Among these 80 (49 male) met the MRI criteria for hydrocephalus, 75 (46 male) had non-communicating hydrocephalus and 5 (3 male) communicating hydrocephalus. Of the patients 24 (15 male) had posthemorrhagic aqueductal stenosis, 16 (8 male) intracranial tumors, 9 (6 male) Chiari II malformations, 5 (4 male) other congenital malformations including malformations of the Dandy Walker spectrum, 9 (3 male) idiopathic aqueductal stenosis, 7 (5 male) arachnoidal cysts and 10 (8 male) other disorders, such as post-infections, macrocephaly cutis marmorata telangiectatica congenita (M-CMTC) syndrome, mesencephalic arteriovenous malformation (AVM), Langerhans cell histiocystosis. It is important to take the age of the patient and the imaging pattern into account and to exclude tumors when reporting MR images of children with hydrocephalus.
A visual description of the dissection of the cerebral surface vasculature and associated meninges and the choroid plexus from rat brain.
Bowyer, John F; Thomas, Monzy; Patterson, Tucker A; George, Nysia I; Runnells, Jeffrey A; Levi, Mark S
This video presentation was created to show a method of harvesting the two most important highly vascular structures, not residing within the brain proper, that support forebrain function. They are the cerebral surface (superficial) vasculature along with associated meninges (MAV) and the choroid plexus which are necessary for cerebral blood flow and cerebrospinal fluid (CSF) homeostasis. The tissue harvested is suitable for biochemical and physiological analysis, and the MAV has been shown to be sensitive to damage produced by amphetamine and hyperthermia. As well, the major and minor cerebral vasculatures harvested in MAV are of potentially high interest when investigating concussive types of head trauma. The MAV dissected in this presentation consists of the pial and some of the arachnoid membrane (less dura) of the meninges and the major and minor cerebral surface vasculature. The choroid plexus dissected is the structure that resides in the lateral ventricles as described by Oldfield and McKinley. The methods used for harvesting these two tissues also facilitate the harvesting of regional cortical tissue devoid of meninges and larger cerebral surface vasculature, and is compatible with harvesting other brain tissues such as striatum, hypothalamus, hippocampus, etc. The dissection of the two tissues takes from 5 to 10 min total. The gene expression levels for the dissected MAV and choroid plexus, as shown and described in this presentation can be found at GSE23093 (MAV) and GSE29733 (choroid plexus) at the NCBI GEO repository. This data has been, and is being, used to help further understand the functioning of the MAV and choroid plexus and how neurotoxic events such as severe hyperthermia and AMPH adversely affect their function.
Ex vivo and in vivo diffusion of ropivacaine through spinal meninges: influence of absorption enhancers.
Brandhonneur, Nolwenn; Dollo, Gilles; Ratajczak-Enselme, Maja; Deniau, Anne Laure; Chevanne, François; Estèbe, Jean Pierre; Legrand, Alain; Le Corre, Pascal
Following epidural administration, cerebrospinal fluid bioavailability of local anesthetics is low, one major limiting factor being diffusion across the arachnoid mater barrier. The aim of this study was to evaluate the influence of absorption enhancers on the meningeal permeability of epidurally administered ropivacaine. Five enhancers known for their ability to increase drug permeability via transcellular and/or paracellular pathways, i.e. palmitoyl carnitine, ethylenediaminetetraacetic acid, sodium caprate, dodecylphosphocholine and pentylglycerol, were tested ex vivo on fresh specimen of meninges removed from cervical to lumbar level of rabbit spine following laminectomy and placed in diffusion chambers. Among them, sodium caprate lead to the best permeability improvement for both marker and drug (440% and 112% for mannitol and ropivacaine, respectively) and was therefore selected for in vivo study in a sheep model using microdialysis technique to evaluate epidural and intrathecal ropivacaine concentrations following epidural administration. Resulting dialysate and plasma concentrations were used to calculate pharmacokinetic parameters. Following sodium caprate pre-treatment, ropivacaine intrathecal maximal concentration (Cmax) was 1.6 times higher (78 ± 16 μg ml(-1) vs 129 ± 26 μg ml(-1), p<0.05) but the influence of the absorption enhancer was only effective the first 30 min following ropivacaine injection, as seen with the significantly increase of intrathecal AUC(0-30 min) (1629 ± 437 μg min ml(-1) vs 2477 ± 559 μg min ml(-1), p<0.05) resulting in a bioavailable fraction 130% higher 30 min after ropivavaine administration. Co-administration of local anesthetics with sodium caprate seems to allow a transient and reversible improvement of transmeningeal passage into intrathecal space. Copyright © 2010 Elsevier B.V. All rights reserved.
A Review of Techniques Used in the Management of Growing Skull Fractures.
Vezina, Noemie; Al-Halabi, Becher; Shash, Hani; Dudley, Roy R; Gilardino, Mirko S
Growing skull fractures (GSFs) are rare complications of pediatric head trauma that comprise skull fractures associated with an underlying dural tear and an intact arachnoid membrane. They are often misdiagnosed, and delay in management can lead to progression of the disease along with its neurological sequelae. Multiple clinical reports and qualitative reviews on this entity exist. To our knowledge, this represents the largest clinical review reporting on established techniques in the management of these fractures. A literature search was performed on the databases Embase, Medline, Cochrane, and PubMed from their inception until February 2015 using the terms "Growing," "Skull," "Fracture," and their equivalent terms. Studies included were case series with 5 or more patients describing GSFs and their management. Twenty-two articles reporting 440 patients were included in the analysis. The mean age at trauma was 8.8 months, with the mean at presentation of 21.9 months and 57.8% of the patients being males. Most commonly, a combined dura-cranioplasty was done in 61.6% of the patients. A range of autoplastic and alloplastic materials were used in both of these techniques. Improvement from preoperative clinical status in seizures and neurological deficits was noted in 18 (12.7%) and 11 (7.05%) of the patients, respectively, following operative repair and medical management. Early recognition is crucial in the management and treatment of GSF. Children at risk for developing GSF should be monitored clinically for up to 3 months following the initial insult. The surgical treatment depends on the size of the fracture and the age of the patient. A summary of the presentation, management, associated outcomes, complications, and recommendations discussed in the literature are reported within.
The Results of Neuroendoscopic Surgery in Patients with Posttraumatic and Posthemorrhagic Hydrocephalus.
Chrastina, Jan; Novák, Zdeněk; Zeman, Tomáš; Feitová, Věra; Hrabovský, Dušan; Říha, Ivo
Posttraumatic hydrocephalus (PTH) and posthemorrhagic hydrocephalus (PHH) were previously considered not suitable for neuroendoscopic treatment. New hydrocephalus theories support possible successful neuroendoscopy in such patients. This study presents the results of neuroendoscopy in PTH and PHH with a background analysis. From 130 hydrocephalic patients after neuroendoscopic surgeries, 35 cases with PTH (n = 11) or PHH (n = 24; acute: n = 9, subacute: n = 10, chronic: n = 5) were found. The success rate (Glasgow Outcome Scale [GOS] score 4 or 5 without shunt) and clinical outcome (GOS score) of endoscopic third ventriculostomy (ETV) were analyzed. During the study period, 34 patients had ventriculoperitoneal shunts implanted, including 2 PTH and 5 PHH patients (all chronic). The success rate of ETV in PTH was 54.5%. In acute PHH, the success rate was 33.3%, 42.8% after excluding devastating hematomas. A post-ETV shunt was implanted in 1 patient (massive subarachnoid hemorrhage [SAH]) with final GOS score of 5. In subacute cases, the ETV success rate was 40% (no post-ETV shunts). In chronic PHH, only 1 patient with a GOS score of 5 was shunt-free (20%). The cause of ETV failure was massive SAH. Low final GOS score was caused by the extent of intracerebral bleeding or extracranial problems. The main indications for primary shunt implantation in PTH and PHH were infectious complications. The rate of good outcomes was 0% in PTH and 40% in PHH. The best results of neuroendoscopy were achieved in PTH and acute PHH. ETV failures were associated with massive SAH; arachnoid cistern blockage and scarring precludes ETV success. Copyright © 2018 Elsevier Inc. All rights reserved.
Perceived Appropriateness of Shared Decision-Making in the Emergency Department: A Survey Study
Probst, Marc A.; Kanzaria, Hemal K.; Frosch, Dominick L.; Hess, Erik P.; Winkel, Gary; Ngai, Ka Ming; Richardson, Lynne D.
Objective To describe perceptions of practicing emergency physicians regarding the appropriateness and medicolegal implications of using shared decision-making (SDM) in the emergency department (ED). Methods We conducted a cross-sectional survey of emergency physicians (EPs) at a large, national professional meeting to assess perceived appropriateness of SDM for different categories of ED management (e.g. diagnostic testing, treatment, disposition) and in common clinical scenarios (e.g. low-risk chest pain, syncope, minor head injury). A 21-item survey instrument was iteratively developed through review by content experts, cognitive testing, and pilot testing. Descriptive and multivariate analyses were conducted. Results We approached 737 EPs; 709 (96%) completed the survey. Two thirds (67.8%) of respondents were male, 51% practiced in an academic setting; 44% in the community. Of the 7 management decision categories presented, SDM was reported to be most frequently appropriate for deciding on invasive procedures (71.5%), computed tomography (CT) scanning (56.7%), and post-ED disposition (56.3%). Among the specific clinical scenarios, use of thrombolytics for acute ischemic stroke was felt to be most frequently appropriate for SDM (83.4%), followed by lumbar puncture to rule out sub-arachnoid hemorrhage (73.8%), and CT head for pediatric minor head injury (69.9%). Most EPs (66.8%) felt that using and documenting SDM would decrease their medicolegal risk while a minority (14.2%) felt it would increase their risk. Conclusions Acceptance of SDM among emergency physicians appears to be strong across management categories (diagnostic testing, treatment, and disposition) and in a variety of clinical scenarios. SDM is perceived by most EPs to be medicolegally protective. PMID:26806170
Perspective View of Venus (Center Latitude 45 Degrees N., Center Longitude 11 Degrees E.)
NASA Technical Reports Server (NTRS)
This perspective view of Venus, generated by computer from Magellan data and color-coded with emissivity, shows part of the lowland plains in Sedna Planitia. Circular depressions with associated fracture patterns called 'coronae' are apparently unique to the lowlands of Venus, and tend to occur in linear clusters along the planet's major tectonic belts. Coronae differ greatly in size and detailed morphology: the central depression may or may not lie below the surrounding plains, and may or may not be surrounded by a raised rim or a moat outside the rim. The corona shown here is relatively small (100 km in diameter and 1 km deep) and is of the subtype known as an 'arachnoid' because of the spider-like configuration of concentric (body) and radial (legs) fractures. Coronae are thought to be caused by localized 'hot spot' magmatic activity in Venus' subsurface. Intrusion of magma into the crust first pushes up the surface, after which cooling and contraction create the central depression and generate a pattern of concentric fractures. In some cases, lava may be extruded onto the surface. The fractured ridge at the left is classified as a 'nova' or 'stellate fracture center' and is believed to represent an early phase of corona formation, in which subsidence due to cooling has not yet created the central depression, and the fracture pattern is still entirely radial. Magellan MIDR quadrangle* containing this image: C1-45N011. Image resolution (m): 225. Size of region shown (E-W x N-S, in km): 439 x 474. Range of emissivities from violet to red: 0.82 -- 0.88. Vertical exaggeration: 100. Azimuth of viewpoint (deg clockwise from East): 150. Elevation of viewpoint (km): 600. *Quadrangle name indicates approximate center latitude (N=north, S=south) and center longitude (East).
C-type natriuretic peptide and atrial natriuretic peptide receptors of rat brain.
Brown, J; Zuo, Z
Natriuretic peptide receptors in rat brain were mapped by in vitro autoradiography using 125I-labeled [Tyr0]CNP-(1-22) to bind atrial natriuretic peptide receptor (ANPR)-B and ANPR-C receptors selectively, and 125I-labeled alpha-ANP to select ANPR-A and ANPR-C receptors. Des-[Gln18,Ser19,Gly20,Leu21,Gly22]ANP-(4- 23)-amide (C-ANP) was used for its selectivity for ANPR-C over ANPR-A. Specific binding of 125I-[Tyr0]CNP-(1-22) with a dissociation constant (Kd) approximately 1 nM occurred in olfactory bulb, cerebral cortex, lateral septal nucleus, choroid plexus, and arachnoid mater. This binding was abolished by C-type natriuretic peptide [CNP-(1-22)], alpha-ANP and C-ANP, and conformed to ANPR-C. 125I-alpha-ANP bound to all structures that bound 125I-[Tyr0]CNP-(1-22). This binding was also inhibited by both CNP-(1-22) and C-ANP, confirming the presence of ANPR-C-like binding sites. However, ANPR-C-like binding sites were heterogenous because only some had high affinities for 125I-[Tyr0]CNP-(1-22) and CNP-(1-22). 125I-alpha-ANP also bound sites without affinities for C-ANP or CNP-(1-22). These sites were consistent with ANPR-A. They occurred mainly on the olfactory bulb, the choroid plexus, and the subfornical organ. Guanosine 3',5'-cyclic monophosphate production was strongly stimulated by alpha-ANP but not by CNP-(1-22) in olfactory bulb. Neither ligand stimulated it in cortical tissue. Thus the natriuretic peptide binding sites of rat brain conformed to ANPR-A and to heterogenous ANPR-C-like sites. No ANPR-B were detected.
AT-47PHASE I TRIAL OF INTRATHECAL TRASTUZUMAB IN HER2 POSITIVE LEPTOMENINGEAL METASTASES
Raizer, Jeffrey; Pentsova, Elena; Omuro, Antonio; Lin, Nancy; Nayak, Lakshmi; Quant, Eudocia; Kumthekar, Priya
INTRODUCTION: Trastuzimab is a humanized monoclonal antibody against Her2 whose limitation is central nervous system penetration that often leads to brain and leptomeningeal metastases (LM) in the setting to controlled systemic HER2 positive breast cancer. We performed a phase I clinical trial of intrathecal (IT) trastuzumab in patients with HER2 positive breast cancer and LM. METHODS: IRB consented patients were treated at defined dose levels; protocol was modified to accelerate dose escalation and increase IT dosage. Dose levels of IT treatment 10 mg, 20 mg, 40 mg, 60 mg and 80 mg were examined. Treatment was given twice a week x4 weeks, then once a week x4 weeks then every other week until progressive disease. MRI was done at 4 week intervals x2 then every 8 weeks. CSF was assessed every other week x2 then every 4 weeks. RESULTS: 13 women with HER2 positive breast cancer, 1 man with a glioblastoma, and one woman with anaplastic ependymoma were enrolled with a median age of 55 (42-67) and median KPS of 80 (60-90). Three patients were treated at the 10mg dose level, three at 20mg, one at 40mg, one at 60mg and 7 at 80mg. At the 80 mg dose level a patient was added as one patient was removed before complete evaluation and another patient had a grade 4 DLT of arachnoiditis. One patient had the Ommaya reservoir removed for infection unrelated to treatment. Data on CSF levels shows therapeutic levels in the patients treated with 10 mg, 20 mg and 40 mg; data analysis on CSF at 60 and 80 mg is pending. CONCLUSION: IT Trastuzumab is well tolerated up to 80 mg IT. Complete CSF PK data will be presented. A phase II study is underway at the 80 mg dose.
Excessive work and risk of haemorrhagic stroke: a nationwide case-control study.
Kim, Beom Joon; Lee, Seung-Hoon; Ryu, Wi-Sun; Kim, Chi Kyung; Chung, Jong-Won; Kim, Dohoung; Park, Hong-Kyun; Bae, Hee-Joon; Park, Byung-Joo; Yoon, Byung-Woo
Adverse effect of excessive work on health has been suggested previously, but it was not documented in cerebrovascular diseases. The authors investigated whether excessive working conditions would associate with increased risk of haemorrhagic stroke. A nationwide matched case-control study database, which contains 940 cases of incident haemorrhagic stroke (498 intracerebral haemorrhages and 442 sub-arachnoid haemorrhages) with 1880 gender- and age- (± 5-year) matched controls, was analysed. Work-related information based on the regular job situation, including type of occupation, regular working time, duration of strenuous activity during regular work and shift work, was gathered through face-to-face interviews. Conditional logistic regression analyses were used for the multivariable analyses. Compared with white-collar workers, blue-collar workers had a higher risk for haemorrhagic stroke (odds ratio, 1.33 [95% confidence interval, 1.06-1.66]). Longer regular working time was associated with increased risk of haemorrhagic stroke [odds ratio, 1.38 (95% confidence interval, 1.05-1.81) for 8-12 h/day; odds ratio, 1.95 (95% confidence interval, 1.33-2.86) for ≥ 13 h/day; compared with ≤ 4 h/day]. Exposure to ≥ 8 h/week of strenuous activity also associated haemorrhagic stroke risk [odds ratio, 1.61 (95% confidence interval, 1.26-2.05); compared with no strenuous activity]. Shift work was not associated with haemorrhagic stroke (P = 0.98). Positive associations between working condition indices and haemorrhagic stroke risk were consistent regardless of haemorrhagic stroke sub-types and current employment status. Blue-collar occupation, longer regular working time and extended duration of strenuous activity during work may relate to an increased risk of haemorrhagic stroke. © 2012 The Authors. International Journal of Stroke © 2012 World Stroke Organization.
Maternally Expressed Gene 3, an imprinted non-coding RNA gene, is associated with meningioma pathogenesis and progression
Zhang, Xun; Gejman, Roger; Mahta, Ali; Zhong, Ying; Rice, Kimberley A.; Zhou, Yunli; Cheunsuchon, Pornsuk; Louis, David N.; Klibanski, Anne
Meningiomas are common tumors, representing 15-25% of all central nervous system tumors. NF2 gene inactivation on chromosome 22 has been shown as an early event in tumorigenesis; however, few factors underlying tumor growth and progression have been identified. Chromosomal abnormalities of 14q32 are often associated with meningioma pathogenesis and progression; therefore it has been proposed that an as yet unidentified tumor suppressor is present at this locus. MEG3 is an imprinted gene located at 14q32 that encodes a non-coding RNA with an anti-proliferative function. We found that MEG3 mRNA is highly expressed in normal arachnoidal cells. However, MEG3 is not expressed in the majority of human meningiomas or the human meningioma cell lines IOMM-Lee and CH157-MN. There is a strong association between loss of MEG3 expression and tumor grade. Allelic loss at the MEG3 locus is also observed in meningiomas, with increasing prevalence in higher grade tumors. In addition, there is an increase in CpG methylation within the promoter and the imprinting control region of MEG3 gene in meningiomas. Functionally, MEG3 suppresses DNA synthesis in both IOMM-Lee and CH157-MN cells by approximately 60% in BrdU incorporation assays. Colony-forming efficiency assays show that MEG3 inhibits colony formation in CH157-MN cells by approximately 80%. Furthermore, MEG3 stimulates p53-mediated transactivation in these cell lines. Therefore, these data are consistent with the hypothesis that MEG3, which encodes a non-coding RNA, may be a tumor suppressor gene at chromosome 14q32 involved in meningioma progression via a novel mechanism. PMID:20179190
Maternally expressed gene 3, an imprinted noncoding RNA gene, is associated with meningioma pathogenesis and progression.
Zhang, Xun; Gejman, Roger; Mahta, Ali; Zhong, Ying; Rice, Kimberley A; Zhou, Yunli; Cheunsuchon, Pornsuk; Louis, David N; Klibanski, Anne
Meningiomas are common tumors, representing 15% to 25% of all central nervous system tumors. NF2 gene inactivation on chromosome 22 has been shown as an early event in tumorigenesis; however, few factors underlying tumor growth and progression have been identified. The chromosomal abnormalities of 14q32 are often associated with meningioma pathogenesis and progression; therefore, it has been proposed that an as yet unidentified tumor suppressor is present at this locus. Maternally expressed gene 3 (MEG3) is an imprinted gene located at 14q32 which encodes a noncoding RNA with an antiproliferative function. We found that MEG3 mRNA is highly expressed in normal arachnoidal cells. However, MEG3 is not expressed in the majority of human meningiomas or the human meningioma cell lines IOMM-Lee and CH157-MN. There is a strong association between loss of MEG3 expression and tumor grade. Allelic loss at the MEG3 locus is also observed in meningiomas, with increasing prevalence in higher grade tumors. In addition, there is an increase in CpG methylation within the promoter and the imprinting control region of MEG3 gene in meningiomas. Functionally, MEG3 suppresses DNA synthesis in both IOMM-Lee and CH157-MN cells by approximately 60% in bromodeoxyuridine incorporation assays. Colony-forming efficiency assays show that MEG3 inhibits colony formation in CH157-MN cells by approximately 80%. Furthermore, MEG3 stimulates p53-mediated transactivation in these cell lines. Therefore, these data are consistent with the hypothesis that MEG3, which encodes a noncoding RNA, may be a tumor suppressor gene at chromosome 14q32 involved in meningioma progression via a novel mechanism.
A balanced view of the cerebrospinal fluid composition and functions: Focus on adult humans.
Spector, Reynold; Robert Snodgrass, S; Johanson, Conrad E
In this review, a companion piece to our recent examination of choroid plexus (CP), the organ that secretes the cerebrospinal fluid (CSF), we focus on recent information in the context of reliable older data concerning the composition and functions of adult human CSF. To accomplish this, we define CSF, examine the methodology employed in studying the CSF focusing on ideal or near ideal experiments and discuss the pros and cons of several widely used analogical descriptions of the CSF including: the CSF as the "third circulation," the CSF as a "nourishing liquor," the similarities of the CSF/choroid plexus to the glomerular filtrate/kidney and finally the CSF circulation as part of the "glymphatic system." We also consider the close interrelationship between the CSF and extracellular space of brain through gap junctions and the paucity of data suggesting that the cerebral capillaries secrete a CSF-like fluid. Recently human CSF has been shown to be in dynamic flux with heart-beat, posture and especially respiration. Functionally, the CSF provides buoyancy, nourishment (e.g., vitamins) and endogenous waste product removal for the brain by bulk flow into the venous (arachnoid villi and nerve roots) and lymphatic (nasal) systems, and by carrier-mediated reabsorptive transport systems in CP. The CSF also presents many exogenous compounds to CP for metabolism or removal, indirectly cleansing the extracellular space of brain (e.g., of xenobiotics like penicillin). The CSF also carries hormones (e.g., leptin) from blood via CP or synthesized in CP (e.g., IGF-2) to the brain. In summary the CP/CSF, the third circulation, performs many functions comparable to the kidney including nourishing the brain and contributing to a stable internal milieu for the brain. These tasks are essential to normal adult brain functioning. Copyright © 2015. Published by Elsevier Inc.
Intraventricular meningiomas: a clinicopathological study and review.
Bhatoe, Harjinder S; Singh, Prakash; Dutta, Vibha
Intraventricular meningiomas are rare tumors. The origin of these tumors can be traced to embryological invagination of arachnoid cells into the choroid plexus. The authors analyzed data that they had collected to study the clinicopathological aspects and review the origin, presentation, imaging, and management of these tumors. In this retrospective analysis, the authors describe the cases of 12 patients who had received a diagnosis of intraventricular meningioma and underwent surgery for the tumors. Nine of these patients were men and three were women. Features of neurofibromatosis Type 2 were present in two of the women. Nine of the tumors were located in the lateral ventricles, one was in the third ventricle, and two were in the fourth ventricle. Raised intracranial pressure (ICP) was the universal presentation in all the patients, and the preoperative diagnoses were confirmed on neuroimaging studies. Excision was performed using the parietooccipital (trigonal) approach for lateral ventricle tumors, the transcortical-transventricular route for the third ventricle tumor, and suboccipital craniectomy for fourth ventricle tumors. Postoperatively, one patient died and the others experienced resolution of their symptoms. Histopathological features of these tumors were similar to those seen in meningiomas in other locations. Intraventricular meningiomas are slow-growing tumors that become large prior to detection. Although they are commonly seen in the lateral ventricles, they occur in the third and fourth ventricles as well. Presentation is in the form of raised ICP with no localizing features; therefore the diagnosis is based on imaging studies. Hydrocephalus occurs due to obstruction of cerebrospinal fluid pathways. Excision requires planning to avoid eloquent cortex incision. The histopathological features are varied, although most of the tumors in the study were angiomatous meningiomas. These tumors are no different histologically from tumors that are dural in
[Combined spinal-epidural anesthesia for cesarean section in a parturient with myotonic dystrophy].
Mori, Kosuke; Mizuno, Ju; Nagaoka, Takehiko; Harashima, Toshiya; Morita, Sigeho
Myotonic dystrophy (MD) is a muscle disorder characterized by progressive muscle wasting and weakness, and is the most common form of muscular dystrophy that begins in adulthood, often after pregnancy. MD might be related to occurrence of malignant hyperthermia. Therefore, the cesarean section is often performed for the parturient with MD. We had an experience of combined spinal-epidural anesthesia for cesarean section in a parturient complicated with MD. A 40-year-old woman had rhabdomyolysis caused by ritodrine at 15-week gestation and was diagnosed as MD by electromyography. Her first baby died due to respiratory failure fourth day after birth. She had hatchet face, slight weakness of her lower extremities, and easy fatigability. Her manual muscle test was 5/5 at upper extremities and 4/5 at lower extremities. She underwent emergency cesarean section for premature rupture of the membrane, weak pain during labor, and obstructed labor at 33-week gestation. We placed an epidural catheter from T12/L1 and punctured arachnoid with 25 G spinal needle. We performed spinal anesthesia using 0.5% hyperbaric bupivacaine 1.5 ml and epidural anesthesia using 2% lidocaine 6 ml. Her anesthetic level reached bilaterally to T7 and operation started 18 minutes after combined spinal-epidural anesthesia. Her baby was born 23 minutes after the anesthesia. As her baby was 1/5 at Apgar score, the baby was tracheally intubated and artificially ventilated. The cesarean section was finished in 33 minutes uneventfully. She had no adverse events and was discharged on the 8th postoperative day. Later her baby was diagnosed as congenital MD by gene analysis. Combined spinal-epidural anesthesia with the amide-typed local anesthetic agents could be useful and safe for cesarean section in the parturient with MD.
Neural System Antigens Are Recognized by Autoantibodies from Patients Affected by a New Variant of Endemic Pemphigus Foliaceus in Colombia
Howard, Michael S.; Yi, Hong; Gao, Weiqing; Hashimoto, Takashi; Grossniklaus, Hans E.
Background Endemic pemphigus foliaceus (EPF), is also known as “fogo selvagem” or “wild fire,” reflecting the intense burning sensation of the skin reported by patients with this disease. Based on this finding, we tested for neural autoreactivity in patients affected by a new variant of EPF (El Bagre-EPF). Methods We tested 20 El Bagre-EPF patients, 20 normal controls from the endemic area, and 20 age- and sex-matched normal controls from outside the endemic area. We tested for autoreactivity to several immunoglobulins and complement. Both human skin and bovine tail were used as antigens. Results We detected autoreactivity to neural structures, mechanoreceptors, nerves, perineural cell layers of the arachnoid envelope around the optic nerve, brain structures, and to neuromuscular spindles; these structures colocalized with several neural markers. The patient antibodies also colocalized with desmoplakins 1 and 2, with the armadillo repeat protein deleted in velo-cardio-facial syndrome and with p0071 antibodies. Autoreactivity was also found associated with neurovascular bundles innervating the skin, and immunoelectron microscopy using protein A gold against patient antibodies was positive against the nerve axons. Paucicellularity of the intraepidermal nerve endings and defragmentation of the neural plexus were seen in 70% of the cases and not in the controls from the endemic area (p<0.005). Neuropsychological and/or behavioral symptoms were detected in individuals from the endemic area, including sensorimotor axonal neuropathy. Conclusions Our findings may explain for the first time the “pose of pemphigus,” representing a dorsiflexural posture seen in EPF patients vis-a-vis the weakness of the extensor nerves, and furthermore, the autoreactivity to nerves in EPF could explain the “burning sensation” encountered in EPF disease. PMID:21210298
Effect of primary empty sella syndrome on pituitary surgery for Cushing's disease.
Mehta, Gautam U; Bakhtian, Kamran D; Oldfield, Edward H
Primary empty sella syndrome (ESS) results from herniation of arachnoid mater into the pituitary fossa. It has been suggested to have a negative effect on pituitary surgery; however, outcomes in this cohort have not been defined. This study was performed to determine the effect of ESS on immediate and long-term biochemical outcome after pituitary surgery for Cushing's disease (CD). Using a matched cohort study design, the authors followed patients treated with pituitary surgery for CD with and without ESS. Complete ESS was defined as pituitary gland height ≤ 2 mm, whereas partial ESS was defined as pituitary gland height > 2 mm but less than three-quarters of the total sellar depth. The primary end points were immediate and long-term biochemical outcome. Cerebrospinal fluid leaks were recorded as a secondary end point. Seventy-eight patients with CD and primary ESS were identified and matched with 78 patients with CD without ESS. After surgical management, immediate biochemical remission was achieved in 69 patients (88%) with ESS and 75 controls (96%, p = 0.10). Long-term remission was achieved in most patients in both groups (5-year cure: 85% vs 92%, p = 0.10). Among patients with ESS, the presence of complete ESS predicted a worse long-term outcome (p = 0.04). Intraoperative CSF leaks were significantly more frequent with ESS (54% vs 24%, p < 0.001), and despite sellar floor repair, the rate of postoperative CSF leaks was also increased (6% vs 3%, p = 0.27). Biochemical outcome after pituitary surgery for CD was worse in patients with complete ESS, and the risk of a CSF leak was increased with both partial and complete ESS. However, as outcome remains superior to those following alternative therapies and the biology of these tumors is unchanged in the setting of ESS, pituitary surgery should remain the initial treatment of choice.
[Pregnancy and childbirth in a patient with a spinal cord lesion].
Vanderbeke, I; Boll, D; Verguts, J K
A 37-year-old woman with a spinal cord lesion at the level of TvIII due to a car-accident, became pregnant. She had posttraumatic syringomyely at Cv-TvIII, for which she underwent syringo-arachnoidal drainage. At approximately six weeks of amenorrhoea she presented at the emergency room with vaginal bleeding. She was treated with dalteparine 5000 IU once daily given by intramuscular injection until 6 weeks post partum. Weekly urine checks were advised. At 36 6/7 weeks of pregnancy, the patient was admitted to hospital for daily cardiotocography and 4-hourly contraction monitoring. After spontaneous rupture of the membranes she went into labour and had a vaginal delivery of a son weighing 3320 g. His Apgar score was 6 after 1 min and 9 after 5 min; arterial pH was 7.31. For three months after giving birth she received specialist care at home as well as help and counselling from a rehabilitation centre. In pregnant women with a spinal cord lesion, special attention should be paid to urinary tract infections, pressure areas, anaemia and thrombo-embolic symptoms. During partus, cardiotocographic monitoring should be carried out, also in patients with TvI-Tx lesions regularly from 36 weeks. In pregnant women with lesions from TvI, medical attendants should be aware of the possibility of autonomous dysreflection. Epidural anaesthesia should be administered and episiotomy or rupture avoided. Post partum, the bladder should always be completely emptied and pressure areas and signs ofthrombo-embolic complications monitored. A urological bladder function consultation should be requested, and, ifepisiotomy or rupture does occur, extra care should be taken to avoid infection. The ergonomic situation at home should be evaluated to ensure that any ergonomic changes necessary for the care of the patient and her newborn, take place in time.
Current management of autosomal dominant polycystic kidney disease.
Akoh, Jacob A
Autosomal dominant polycystic kidney disease (ADPKD), the most frequent cause of genetic renal disease affecting approximately 4 to 7 million individuals worldwide and accounting for 7%-15% of patients on renal replacement therapy, is a systemic disorder mainly involving the kidney but cysts can also occur in other organs such as the liver, pancreas, arachnoid membrane and seminal vesicles. Though computed tomography and magnetic resonance imaging (MRI) were similar in evaluating 81% of cystic lesions of the kidney, MRI may depict septa, wall thickening or enhancement leading to upgrade in cyst classification that can affect management. A screening strategy for intracranial aneurysms would provide 1.0 additional year of life without neurological disability to a 20-year-old patient with ADPKD and reduce the financial impact on society of the disease. Current treatment strategies include reducing: cyclic adenosine monophosphate levels, cell proliferation and fluid secretion. Several randomised clinical trials (RCT) including mammalian target of rapamycin inhibitors, somatostatin analogues and a vasopressin V2 receptor antagonist have been performed to study the effect of diverse drugs on growth of renal and hepatic cysts, and on deterioration of renal function. Prophylactic native nephrectomy is indicated in patients with a history of cyst infection or recurrent haemorrhage or to those in whom space must be made to implant the graft. The absence of large RCT on various aspects of the disease and its treatment leaves considerable uncertainty and ambiguity in many aspects of ADPKD patient care as it relates to end stage renal disease (ESRD). The outlook of patients with ADPKD is improving and is in fact much better than that for patients in ESRD due to other causes. This review highlights the need for well-structured RCTs as a first step towards trying newer interventions so as to develop updated clinical management guidelines.
Risk of Recurrence in Operated Parasagittal Meningiomas: A Logistic Binary Regression Model.
Escribano Mesa, José Alberto; Alonso Morillejo, Enrique; Parrón Carreño, Tesifón; Huete Allut, Antonio; Narro Donate, José María; Méndez Román, Paddy; Contreras Jiménez, Ascensión; Pedrero García, Francisco; Masegosa González, José
Parasagittal meningiomas arise from the arachnoid cells of the angle formed between the superior sagittal sinus (SSS) and the brain convexity. In this retrospective study, we focused on factors that predict early recurrence and recurrence times. We reviewed 125 patients with parasagittal meningiomas operated from 1985 to 2014. We studied the following variables: age, sex, location, laterality, histology, surgeons, invasion of the SSS, Simpson removal grade, follow-up time, angiography, embolization, radiotherapy, recurrence and recurrence time, reoperation, neurologic deficit, degree of dependency, and patient status at the end of follow-up. Patients ranged in age from 26 to 81 years (mean 57.86 years; median 60 years). There were 44 men (35.2%) and 81 women (64.8%). There were 57 patients with neurologic deficits (45.2%). The most common presenting symptom was motor deficit. World Health Organization grade I tumors were identified in 104 patients (84.6%), and the majority were the meningothelial type. Recurrence was detected in 34 cases. Time of recurrence was 9 to 336 months (mean: 84.4 months; median: 79.5 months). Male sex was identified as an independent risk for recurrence with relative risk 2.7 (95% confidence interval 1.21-6.15), P = 0.014. Kaplan-Meier curves for recurrence had statistically significant differences depending on sex, age, histologic type, and World Health Organization histologic grade. A binary logistic regression was made with the Hosmer-Lemeshow test with P > 0.05; sex, tumor size, and histologic type were used in this model. Male sex is an independent risk factor for recurrence that, associated with other factors such tumor size and histologic type, explains 74.5% of all cases in a binary regression model. Copyright © 2017 Elsevier Inc. All rights reserved.
A Visual Description of the Dissection of the Cerebral Surface Vasculature and Associated Meninges and the Choroid Plexus from Rat Brain
Bowyer, John F.; Thomas, Monzy; Patterson, Tucker A.; George, Nysia I.; Runnells, Jeffrey A.; Levi, Mark S.
This video presentation was created to show a method of harvesting the two most important highly vascular structures, not residing within the brain proper, that support forebrain function. They are the cerebral surface (superficial) vasculature along with associated meninges (MAV) and the choroid plexus which are necessary for cerebral blood flow and cerebrospinal fluid (CSF) homeostasis. The tissue harvested is suitable for biochemical and physiological analysis, and the MAV has been shown to be sensitive to damage produced by amphetamine and hyperthermia 1,2. As well, the major and minor cerebral vasculatures harvested in MAV are of potentially high interest when investigating concussive types of head trauma. The MAV dissected in this presentation consists of the pial and some of the arachnoid membrane (less dura) of the meninges and the major and minor cerebral surface vasculature. The choroid plexus dissected is the structure that resides in the lateral ventricles as described by Oldfield and McKinley3,4,5,6. The methods used for harvesting these two tissues also facilitate the harvesting of regional cortical tissue devoid of meninges and larger cerebral surface vasculature, and is compatible with harvesting other brain tissues such as striatum, hypothalamus, hippocampus, etc. The dissection of the two tissues takes from 5 to 10 min total. The gene expression levels for the dissected MAV and choroid plexus, as shown and described in this presentation can be found at GSE23093 (MAV) and GSE29733 (choroid plexus) at the NCBI GEO repository. This data has been, and is being, used to help further understand the functioning of the MAV and choroid plexus and how neurotoxic events such as severe hyperthermia and AMPH adversely affect their function. PMID:23183685
Intravital Imaging of a Massive Lymphocyte Response in the Cortical Dura of Mice after Peripheral Infection by Trypanosomes
Coles, Jonathan A.; Myburgh, Elmarie; Ritchie, Ryan; Hamilton, Alana; Rodgers, Jean; Mottram, Jeremy C.; Barrett, Michael P.; Brewer, James M.
Peripheral infection by Trypanosoma brucei, the protozoan responsible for sleeping sickness, activates lymphocytes, and, at later stages, causes meningoencephalitis. We have videoed the cortical meninges and superficial parenchyma of C56BL/6 reporter mice infected with T.b.brucei. By use of a two-photon microscope to image through the thinned skull, the integrity of the tissues was maintained. We observed a 47-fold increase in CD2+ T cells in the meninges by 12 days post infection (dpi). CD11c+ dendritic cells also increased, and extravascular trypanosomes, made visible either by expression of a fluorescent protein, or by intravenous injection of furamidine, appeared. The likelihood that invasion will spread from the meninges to the parenchyma will depend strongly on whether the trypanosomes are below the arachnoid membrane, or above it, in the dura. Making use of optical signals from the skull bone, blood vessels and dural cells, we conclude that up to 40 dpi, the extravascular trypanosomes were essentially confined to the dura, as were the great majority of the T cells. Inhibition of T cell activation by intraperitoneal injection of abatacept reduced the numbers of meningeal T cells at 12 dpi and their mean speed fell from 11.64 ± 0.34 μm/min (mean ± SEM) to 5.2 ± 1.2 μm/min (p = 0.007). The T cells occasionally made contact lasting tens of minutes with dendritic cells, indicative of antigen presentation. The population and motility of the trypanosomes tended to decline after about 30 dpi. We suggest that the lymphocyte infiltration of the meninges may later contribute to encephalitis, but have no evidence that the dural trypanosomes invade the parenchyma. PMID:25881126
“Stealth cranioplasty:” A novel endeavor for symptomatic adult Chiari I patients with syringomyelia: Technical note, appraisal, and philosophical considerations
Rahman, Asifur; Rana, Md. Sumon; Bhandari, Paawan Bahadur; Asif, Dewan Shamsul; Uddin, Abu Naim Wakil; Obaida, Abu Saleh Mohammad Abu; Rahman, Md. Atikur; Alam, Md. Shamsul
Aim and Objective: In this article, we describe a novel technique of reconstruction of posterior fossa by cranioplasty with use of preshaped titanium mesh following posterior fossa decompression (PFD) for Chiari malformation type I (CMI) with syringomyelia (SM) in symptomatic adults. Materials and Methods: Eleven patients underwent limited PFD and expansive cranioplasty with preshaped titanium mesh, what we term as “Stealth Cranioplasty” (SCP), following arachnoid preserving duraplasty (APD) and hexagonal tenting of the duraplasty with the cranioplasty (HTDC) for the management of symptomatic adult CMI with SM. All these patients had syringes extending from 3 to >10 vertebral levels. Results: Seven male and four female symptomatic CMI adult patients, between age ranges of 22 and 44 years (mean 29.45 years), presented with different neurological symptoms related to CMI and SM for 6–84 months (mean 37.09 months). All the patients underwent PFD, APD followed by SCP and HTDC and were followed up for 7–54 months (mean 35.90 months). Of 11 patients, 8 patients improved according to the Chicago Chiari Outcome Scale (CCOS) with score of 13–15 while 3 patients remained unchanged with CCOS of 12, and there was no worsening. There was no complication related to Chiari surgery in any of the patients. All the patients had good reestablishment of cisterna magna. Two patients had marked reduction of syrinx while eight patients had moderate-to-mild reduction and one patient had no change of syrinx. None of the patients needed redo surgery. Conclusion: SCP is an effective, fruitful, and cost-effective technique for the management of symptomatic adult CMI with SM. This technique has the advantages of preventing complications and recurrences in addition to the improvement of symptoms by addressing the basic pathology. PMID:29021676
Functional Redundancy and Complementarities of Seed Dispersal by the Last Neotropical Megafrugivores
Bueno, Rafael S.; Guevara, Roger; Ribeiro, Milton C.; Culot, Laurence; Bufalo, Felipe S.; Galetti, Mauro
Background Functional redundancy has been debated largely in ecology and conservation, yet we lack detailed empirical studies on the roles of functionally similar species in ecosystem function. Large bodied frugivores may disperse similar plant species and have strong impact on plant recruitment in tropical forests. The two largest frugivores in the neotropics, tapirs (Tapirus terrestris) and muriquis (Brachyteles arachnoides) are potential candidates for functional redundancy on seed dispersal effectiveness. Here we provide a comparison of the quantitative, qualitative and spatial effects on seed dispersal by these megafrugivores in a continuous Brazilian Atlantic forest. Methodology/Principal Findings We found a low overlap of plant species dispersed by both muriquis and tapirs. A group of 35 muriquis occupied an area of 850 ha and dispersed 5 times more plant species, and 13 times more seeds than 22 tapirs living in the same area. Muriquis dispersed 2.4 times more seeds in any random position than tapirs. This can be explained mainly because seed deposition by muriquis leaves less empty space than tapirs. However, tapirs are able to disperse larger seeds than muriquis and move them into sites not reached by primates, such as large forest gaps, open areas and fragments nearby. Based on published information we found 302 plant species that are dispersed by at least one of these megafrugivores in the Brazilian Atlantic forest. Conclusions/Significance Our study showed that both megafrugivores play complementary rather than redundant roles as seed dispersers. Although tapirs disperse fewer seeds and species than muriquis, they disperse larger-seeded species and in places not used by primates. The selective extinction of these megafrugivores will change the spatial seed rain they generate and may have negative effects on the recruitment of several plant species, particularly those with large seeds that have muriquis and tapirs as the last living seed dispersers. PMID
Functional redundancy and complementarities of seed dispersal by the last neotropical megafrugivores.
Bueno, Rafael S; Guevara, Roger; Ribeiro, Milton C; Culot, Laurence; Bufalo, Felipe S; Galetti, Mauro
Functional redundancy has been debated largely in ecology and conservation, yet we lack detailed empirical studies on the roles of functionally similar species in ecosystem function. Large bodied frugivores may disperse similar plant species and have strong impact on plant recruitment in tropical forests. The two largest frugivores in the neotropics, tapirs (Tapirus terrestris) and muriquis (Brachyteles arachnoides) are potential candidates for functional redundancy on seed dispersal effectiveness. Here we provide a comparison of the quantitative, qualitative and spatial effects on seed dispersal by these megafrugivores in a continuous Brazilian Atlantic forest. We found a low overlap of plant species dispersed by both muriquis and tapirs. A group of 35 muriquis occupied an area of 850 ha and dispersed 5 times more plant species, and 13 times more seeds than 22 tapirs living in the same area. Muriquis dispersed 2.4 times more seeds in any random position than tapirs. This can be explained mainly because seed deposition by muriquis leaves less empty space than tapirs. However, tapirs are able to disperse larger seeds than muriquis and move them into sites not reached by primates, such as large forest gaps, open areas and fragments nearby. Based on published information we found 302 plant species that are dispersed by at least one of these megafrugivores in the Brazilian Atlantic forest. Our study showed that both megafrugivores play complementary rather than redundant roles as seed dispersers. Although tapirs disperse fewer seeds and species than muriquis, they disperse larger-seeded species and in places not used by primates. The selective extinction of these megafrugivores will change the spatial seed rain they generate and may have negative effects on the recruitment of several plant species, particularly those with large seeds that have muriquis and tapirs as the last living seed dispersers.
Prospective transfrontal sheep model of skull-base reconstruction using vascularized mucosa.
Mueller, Sarina K; Scangas, George; Amiji, Mansor M; Bleier, Benjamin S
No high-fidelity animal model exists to examine prospective wound healing following vascularized reconstruction of the skull base. Such a model would require the ability to study the prospective behavior of vascularized mucosal repairs of large dural and arachnoid defects within the intranasal environment. The objective of this study was to therefore develop and validate a novel, in vivo, transfrontal sheep model of cranial base repair using vascularized sinonasal mucosa. Twelve transfrontal craniotomy and 1.5-cm durotomy reconstructions were performed in 60-kg to 70-kg Dorset/Ovis Aries sheep using vascularized mucosa with or without an adjunctive Biodesign™ underlay graft (n = 6 per group). Histologic outcomes were graded (scale, 0 to 4) by a blinded veterinary histopathologist after 7, 14, and 28 days for a range of wound healing parameters. All sheep tolerated the surgery, which required 148 ± 33 minutes. By day 7, the mucosa was fully adherent with complete partitioning of the sinus and intracranial compartments. Fibroblast infiltration and flap neovascularization scores significantly increased between day 7 (0.3 ± 0.5 and 0.0 ± 0.0) and day 28 (4.0 ± 0.0, p = 0.01 and 2.0 ± 0.8, p = 0.01; respectively), while hemorrhage scores significantly decreased from 2.5 ± 0.6 to 0.0 ± 0.0 (p = 0.01). The inflammatory scores were not significantly different between the heterologous graft and control sides. The described sheep model accurately reflects prospective intranasal wound healing following vascularized mucosal reconstruction of dural defects. This model can be used in future studies to examine novel reconstructive materials, tissue glues, and transmucosal drug delivery to the central nervous system. © 2017 ARS-AAOA, LLC.
Intramedullary dermoid cyst infection mimicking holocord tumor: should radical resection be mandatory?-a case report.
Karaaslan, Burak; Ülkü, Göktuğ; Ucar, Murat; Demirdağ, Tuğba Bedir; İnan, Arda; Börcek, Alp Özgün
spinal canal. Also, CSF circulation alteration due to arachnoiditis may be another etiological factor. The most important entities on outcome are appropriate surgical treatment and antibiotic administration.
Expert clinical reasoning and pain assessment in mechanically ventilated patients: A descriptive study.
Gerber, Anne; Thevoz, Anne-Laure; Ramelet, Anne-Sylvie
Pain assessment in mechanically ventilated patients is challenging, because nurses need to decode pain behaviour, interpret pain scores, and make appropriate decisions. This clinical reasoning process is inherent to advanced nursing practice, but is poorly understood. A better understanding of this process could contribute to improved pain assessment and management. This study aimed to describe the indicators that influence expert nurses' clinical reasoning when assessing pain in critically ill nonverbal patients. This descriptive observational study was conducted in the adult intensive care unit (ICU) of a tertiary referral hospital in Western Switzerland. A purposive sample of expert nurses, caring for nonverbal ventilated patients who received sedation and analgesia, were invited to participate in the study. Data were collected in "real life" using recorded think-aloud combined with direct non-participant observation and brief interviews. Data were analysed using deductive and inductive content analyses using a theoretical framework related to clinical reasoning and pain. Seven expert nurses with an average of 7.85 (±3.1) years of critical care experience participated in the study. The patients had respiratory distress (n=2), cardiac arrest (n=2), sub-arachnoid bleeding (n=1), and multi-trauma (n=2). A total of 1344 quotes in five categories were identified. Patients' physiological stability was the principal indicator for making decision in relation to pain management. Results also showed that it is a permanent challenge for nurses to discriminate situations requiring sedation from situations requiring analgesia. Expert nurses mainly used working knowledge and patterns to anticipate and prevent pain. Patient's clinical condition is important for making decision about pain in critically ill nonverbal patients. The concept of pain cannot be assessed in isolation and its assessment should take the patient's clinical stability and sedation into account. Further
Dengue fever with diffuse cerebral hemorrhages, subdural hematoma and cranial diabetes insipidus.
Jayasinghe, Nayomi Shermila; Thalagala, Eranga; Wattegama, Milanka; Thirumavalavan, Kanapathipillai
Neurological manifestations in dengue fever occur in <1 % of the patients and known to be due to multisystem dysfunction secondary to vascular leakage. Occurrence of wide spread cerebral haemorrhages with subdural hematoma during the leakage phase without profound thrombocytopenia and occurrence of cranial diabetes insipidus are extremely rare and had not been reported in published literature earlier, thus we report the first case. A 24 year old previously healthy lady was admitted on third day of fever with thrombocytopenia. Critical phase started on fifth day with evidence of pleural effusion and moderate ascites. Thirty one hours into critical phase she developed headache, altered level of consciousness, limb rigidity and respiratory depression without definite seizures. Non-contrast CT brain done at tertiary care level revealed diffuse intracranial haemorrhages and sub arachnoid haemorrhages in right frontal, parietal, occipital lobes and brainstem, cerebral oedema with an acute subdural hematoma in right temporo- parietal region. Her platelet count was 40,000 at this time with signs of vascular leakage. She was intubated and ventilated with supportive care. Later on she developed features of cranial diabetes insipidus and it responded to intranasal desmopressin therapy. In spite of above measures signs of brainstem herniation developed and she succumbed to the illness on day 8. Dengue was confirmed serologically. Exact pathophysiological mechanism of diffuse cerebral haemorrhages without profound thrombocytopenia is not well understood. Increased awareness and high degree of clinical suspicion is needed among clinicians for timely diagnosis of this extremely rare complication of dengue fever. We postulate that immunological mechanisms may play a role in pathogenesis. However further comprehensive research and studies are needed to understand the pathophysiological mechanisms leading to this complication.
Hindlimb Suspension (HLS) in Rodents for the Study of Intracranial Pressure, Molecular and Histologic Changes in the Eye, and CSF Production Regulation and Resorption: A Status Report of Two Studies
NASA Technical Reports Server (NTRS)
Theriot, C. A.; Taibbi, G.; Vizzeri, G.; Parsons-Wingerter, P.; Chevez-Barrios, P.; Rivera, A.; Zanello, S. B.
This status report corresponds to two studies tied to an animal experiment being executed at the University of California Davis (Charles Fuller's laboratory). The animal protocol uses the well-documented rat hindlimb suspension (HLS) model, to examine the relationship between cephalic fluid shifts and the regulation of intracranial (ICP) and intraocular (IOP) pressures as well as visual system structure and function. Long Evans rats are subjected to HLS durations of 7, 14, 28 and 90 days. Subgroups of the 90-day animals are studied for recovery periods of 7, 14, 28 or 90 days. All HLS subjects have age-matched cage controls. Various animal cohorts are planned for this study: young males, young females and old males. In addition to the live measures (ICP by telemetry, IOP and retinal parameters by optical coherence tomography) which are shared with the Fuller study, the specific outcomes for this study include: -Gene expression analysis of the retina -Histologic analysis - Analysis of the microvasculature of retina flat mounts by NASA's VESsel GENeration Analysis (VESGEN) Software. To date, the young male and female cohorts are being completed. Due to the need to keep technical variation to a minimum, the histologic and genomic analyses have been delayed until all samples from each cohort are available and can be processed in a single batch per cohort. The samples received so far correspond to young males sacrificed at 7,14, 28 and 90 days of HLS and at 90 days of recovery; and from young females sacrificed at 7, 14 and 28 of HLS. A complementary study titled: "A gene expression and histologic approach to the study of cerebrospinal fluid (CSF) production and outflow in hindlimb suspended rats" seeks to study the molecular components of CSF production and outflow modulation as a result of HLS, bringing a molecular and histologic approach to investigate genome wide expression changes in the arachnoid villi and choroid plexus of HLS rats compared to rats in normal
Identification of a basic protein of Mr 75,000 as an accessory desmosomal plaque protein in stratified and complex epithelia.
Kapprell, H P; Owaribe, K; Franke, W W
Desmosomes are intercellular adhering junctions characterized by a special structure and certain obligatory constituent proteins such as the cytoplasmic protein, desmoglein. Desmosomal fractions from bovine muzzle epidermis contain, in addition, a major polypeptide of Mr approximately 75,000 ("band 6 protein") which differs from all other desmosomal proteins so far identified by its positive charge (isoelectric at pH approximately 8.5 in the denatured state) and its avidity to bind certain type I cytokeratins under stringent conditions. We purified this protein from bovine muzzle epidermis and raised antibodies to it. Using affinity-purified antibodies, we identified a protein of identical SDS-PAGE mobility and isoelectric pH in all epithelia of higher complexity, including representatives of stratified, complex (pseudostratified) and transitional epithelia as well as benign and malignant human tumors derived from such epithelia. Immunolocalization studies revealed the location of this protein along cell boundaries in stratified and complex epithelia, often resolved into punctate arrays. In some epithelia it seemed to be restricted to certain cell types and layers; in rat cornea, for example, it was only detected in upper strata. Electron microscopic immunolocalization showed that this protein is a component of the desmosomal plaque. However, it was not found in the desmosomes of all simple epithelia examined, in the tumors and cultured cells derived thereof, in myocardiac and Purkinje fiber cells, in arachnoideal cells and meningiomas, and in dendritic reticulum cells of lymphoid tissue, i.e., all cells containing typical desmosomes. The protein was also absent in all nondesmosomal adhering junctions. From these results we conclude that this basic protein is not an obligatory desmosomal plaque constituent but an accessory component specific to the desmosomes of certain kinds of epithelial cells with stratified tissue architecture. This suggests that the Mr 75
The anterior temporal artery: an underutilized but robust donor for revascularization of the distal middle cerebral artery.
Tayebi Meybodi, Ali; Lawton, Michael T; Griswold, Dylan; Mokhtari, Pooneh; Payman, Andre; Benet, Arnau
OBJECTIVE The anterior temporal artery (ATA) supplies an area of the brain that, if sacrificed, does not cause a noticeable loss of function. Therefore, the ATA may be used as a donor in intracranial-intracranial (IC-IC) bypass procedures. The capacities of the ATA as a donor have not been studied previously. In this study, the authors assessed the feasibility of using the ATA as a donor for revascularization of different segments of the distal middle cerebral artery (MCA). METHODS The ATA was studied in 15 cadaveric specimens (8 heads, excluding 1 side). First, the cisternal segment of the artery was untethered from arachnoid adhesions and small branches feeding the anterior temporal lobe and insular cortex, to evaluate its capacity for a side-to-side bypass to insular, opercular, and cortical segments of the MCA. Any branch entering the anterior perforated substance was preserved. Then, the ATA was cut at the opercular-cortical junction and the capacity for an end-to-side bypass was assessed. RESULTS From a total of 17 ATAs, 4 (23.5%) arose as an early MCA branch. The anterior insular zone and the frontal parasylvian cortical arteries were the best targets (in terms of mobility and caliber match) for a side-to-side bypass. Most of the insula was accessible for end-to-side bypass, but anterior zones of the insula were more accessible than posterior zones. End-to-side bypass was feasible for most recipient cortical arteries along the opercula, except for posterior temporal and parietal regions. Early ATAs reached significantly farther on the insular MCA recipients than non-early ATAs for both side-to-side and end-to-side bypasses. CONCLUSIONS The ATA is a robust arterial donor for IC-IC bypass procedures, including side-to-side and end-to-side techniques. The evidence provided in this work supports the use of the ATA as a donor for distal MCA revascularization in well-selected patients.
An improved electronic twist-drill craniostomy procedure with post-operative urokinase instillation in treating chronic subdural hematoma.
Lu, Jing; Shen, Dongwei; Hu, Fangjin; Zhou, Jianjun; Lan, Folin; Guo, Dongbing; Liu, Tianqing
Twist-drill craniostomy (TDC) with closed-system drainage is a less invasive surgical technique for the treatment of chronic subdural hematoma (CSDH), but results in a higher disease recurrence rate. Therefore, we aimed to modify the TDC procedure in order to reduce the recurrence rate and further decrease complications. We retrospectively reviewed 230 cases of standard CSDH in 202 patients treated in our hospital between January 2006 and December 2013. We employed a new TDC device called micro-steel-needle-tube-bit for puncture and drainage. We chose an entry point 0.5cm anterior to the coronal suture at the superior temporal line and maintained post-operative drainage with urokinase instillation into the hematoma cavity. Clinical performance was assessed and compared by the Markwalder Grading Scale (MGS) score during the pre-operative period and at discharge. Recurrence of CSDH and complications were also recorded. Mean operation time was only 8.9 (6-13) min. Mean catheter indwelling duration and hospital stay were 1.18 (271/230, 1-3) and 2.27 (458/202, 2-9) days, respectively. The average frequency of urokinase instillation was 1.14 (262/230, 1-3) times. Intracerebral and sub-arachnoid hemorrhages were found in one patient, but were not in the puncture pathway. No perioperative deaths occurred. Recurrence was observed in only one patient at 28 days post-operation. Among 202 patients, 193 (95.54%) showed improved clinical symptoms and neurological function, and significantly lower MGS scores at discharge than pre-operation (0.13±0.45 vs. 1.37±0.55, P<0.01). In conclusion, electric TDC with micro-steel-needle-tube-bit at the pre-coronal suture entry point might be a safer, simpler, and faster mini-invasive surgical procedure for CSDH treatment. Post-operative drainage with instillation of urokinase could dramatically shorten drainage time and decrease recurrence rate. Copyright © 2015 Elsevier B.V. All rights reserved.
A New Methodology of Viewing Extra-Axial Fluid and Cortical Abnormalities in Children with Autism via Transcranial Ultrasonography
Bradstreet, James Jeffrey; Pacini, Stefania; Ruggiero, Marco
Background: Autism spectrum disorders (ASDs) are developmental conditions of uncertain etiology which have now affected more than 1% of the school-age population of children in many developed nations. Transcranial ultrasonography (TUS) via the temporal bone appeared to be a potential window of investigation to determine the presence of both cortical abnormalities and increased extra-axial fluid (EAF). Methods: TUS was accomplished using a linear probe (10–5 MHz). Parents volunteered ASD subjects (N = 23; males 18, females 5) for evaluations (mean = 7.46 years ± 3.97 years), and 15 neurotypical siblings were also examined (mean = 7.15 years ± 4.49 years). Childhood Autism Rating Scale (CARS2®) scores were obtained and the ASD score mean was 48.08 + 6.79 (Severe). Results: Comparisons of the extra-axial spaces indicated increases in the ASD subjects. For EAF we scored based on the gyral summit distances between the arachnoid membrane and the cortical pia layer (subarachnoid space): (1) <0.05 cm, (2) 0.05–0.07 cm, (3) 0.08–0.10 cm, (4) >0.10 cm. All of the neurotypical siblings scored 1, whereas the ASD mean score was 3.41 ± 0.67. We also defined cortical dysplasia as the following: hypoechoic lesions within the substance of the cortex, or disturbed layering within the gray matter. For cortical dysplasia we scored: (1) none observed, (2) rare hypoechogenic lesions and/or mildly atypical cortical layering patterns, (3) more common, but separated areas of cortical hypoechogenic lesions, (4) very common or confluent areas of cortical hypoechogenicity. Again all of the neurotypical siblings scored 1, while the ASD subjects’ mean score was 2.79 ± 0.93. Conclusion: TUS may be a useful screening technique for children at potential risk of ASDs which, if confirmed with repeated studies and high resolution MRI, provides rapid, non-invasive qualification of EAF, and cortical lesions. PMID:24459462
Comparison of 4D Phase-Contrast MRI Flow Measurements to Computational Fluid Dynamics Simulations of Cerebrospinal Fluid Motion in the Cervical Spine
Yiallourou, Theresia I.; Kröger, Jan Robert; Stergiopulos, Nikolaos; Maintz, David
Cerebrospinal fluid (CSF) dynamics in the cervical spinal subarachnoid space (SSS) have been thought to be important to help diagnose and assess craniospinal disorders such as Chiari I malformation (CM). In this study we obtained time-resolved three directional velocity encoded phase-contrast MRI (4D PC MRI) in three healthy volunteers and four CM patients and compared the 4D PC MRI measurements to subject-specific 3D computational fluid dynamics (CFD) simulations. The CFD simulations considered the geometry to be rigid-walled and did not include small anatomical structures such as nerve roots, denticulate ligaments and arachnoid trabeculae. Results were compared at nine axial planes along the cervical SSS in terms of peak CSF velocities in both the cranial and caudal direction and visual interpretation of thru-plane velocity profiles. 4D PC MRI peak CSF velocities were consistently greater than the CFD peak velocities and these differences were more pronounced in CM patients than in healthy subjects. In the upper cervical SSS of CM patients the 4D PC MRI quantified stronger fluid jets than the CFD. Visual interpretation of the 4D PC MRI thru-plane velocity profiles showed greater pulsatile movement of CSF in the anterior SSS in comparison to the posterior and reduction in local CSF velocities near nerve roots. CFD velocity profiles were relatively uniform around the spinal cord for all subjects. This study represents the first comparison of 4D PC MRI measurements to CFD of CSF flow in the cervical SSS. The results highlight the utility of 4D PC MRI for evaluation of complex CSF dynamics and the need for improvement of CFD methodology. Future studies are needed to investigate whether integration of fine anatomical structures and gross motion of the brain and/or spinal cord into the computational model will lead to a better agreement between the two techniques. PMID:23284970
Stroke incidence and 30-day and six-month case fatality rates in Udine, Italy: a population-based prospective study.
Janes, Francesco; Gigli, Gian Luigi; D'Anna, Lucio; Cancelli, Iacopo; Perelli, Anna; Canal, Giessica; Russo, Valentina; Zanchettin, Barbara; Valente, Mariarosaria
Stroke incidence in high-income countries is reported to decrease, and new data on stroke incidence and outcome are needed to design stroke services and to ameliorate stroke management. This study is part of a two-year prospective community-based registry of all cerebrovascular events in the district of Udine (153,312 inhabitants), Friuli-Venezia Giulia region, northeast of Italy, between 1 April 2007 and 31 March 2009. Overlapping sources for case finding were used, combining hot and cold pursuit. We identified 784 stroke cases, 640 (81.6%) incident. The crude overall annual incidence rate per 100,000 residents was 256 (95% confidence interval 241-271) for all strokes and 209 (95% confidence interval 195-223) for first-ever strokes. Incidence rate for first-ever strokes was 181 (95% confidence interval 155-211) after adjustment to the 2007 Italian population and 104 (95% confidence interval 88-122) compared with the European standard population. Incidence rates for first-ever strokes was 215 (196-235) for women, 202 (183-223) for men. Crude annual incidence rates per 100,000 population were 167 (153-178) for ischemic stroke, 31 (26-37) for intracerebral hemorrhage, 8.1 (5.7-11.4) for sub-arachnoid hemorrhage, and 4.6 (2.8-7.1) for undetermined stroke. Overall case fatality rates for first-ever stroke were 20.6% at 28 days and 30.2% at 180 days. Our study shows incidence rates higher than previously reported in our region but not supporting the view of higher incidence rates in Northern than in Southern Italy. Results contribute to time-trends analysis on epidemiology, useful for dimensioning services in Italy and show the persistence of a gap between the outcome of stroke in Italy and that of the best performing European countries, urging to adopt better stroke management plans. © 2013 The Authors. International Journal of Stroke © 2013 World Stroke Organization.
Ocean acidification has little effect on developmental thermal windows of echinoderms from Antarctica to the tropics.
Karelitz, Sam E; Uthicke, Sven; Foo, Shawna A; Barker, Mike F; Byrne, Maria; Pecorino, Danilo; Lamare, Miles D
As the ocean warms, thermal tolerance of developmental stages may be a key driver of changes in the geographical distributions and abundance of marine invertebrates. Additional stressors such as ocean acidification may influence developmental thermal windows and are therefore important considerations for predicting distributions of species under climate change scenarios. The effects of reduced seawater pH on the thermal windows of fertilization, embryology and larval morphology were examined using five echinoderm species: two polar (Sterechinus neumayeri and Odontaster validus), two temperate (Fellaster zelandiae and Patiriella regularis) and one tropical (Arachnoides placenta). Responses were examined across 12-13 temperatures ranging from -1.1 °C to 5.7 °C (S. neumayeri), -0.5 °C to 10.7 °C (O. validus), 5.8 °C to 27 °C (F. zelandiae), 6.0 °C to 27.1 °C (P. regularis) and 13.9 °C to 34.8 °C (A. placenta) under present-day and near-future (2100+) ocean acidification conditions (-0.3 pH units) and for three important early developmental stages 1) fertilization, 2) embryo (prehatching) and 3) larval development. Thermal windows for fertilization were broad and were not influenced by a pH decrease. Embryological development was less thermotolerant. For O. validus, P. regularis and A. placenta, low pH reduced normal development, albeit with no effect on thermal windows. Larval development in all five species was affected by both temperature and pH; however, thermal tolerance was not reduced by pH. Results of this study suggest that in terms of fertilization and development, temperature will remain as the most important factor influencing species' latitudinal distributions as the ocean continues to warm and decrease in pH, and that there is little evidence of a synergistic effect of temperature and ocean acidification on the thermal control of species ranges. © 2016 John Wiley & Sons Ltd.
Cauda equina syndrome following an uneventful spinal anesthesia in a patient undergoing drainage of the Bartholin abscess: A case report.
Merino-Urrutia, Waldo; Villagrán-Schmidt, Milca; Ulloa-Vásquez, Priscilla; Carrasco-Moyano, Rubén; Uribe, Alberto; Stoicea, Nicoleta; Bergese, Sergio D
Neuraxial anesthesia is a commonly used type of regional anesthesia. Cauda equina syndrome is an unusual and severe complication of neuraxial anesthesia, and is caused by damage to the sacral roots of the neural canal. We present a case of cauda equina syndrome following spinal anesthesia in a patient who underwent Bartholin abscess drainage. A 23-year old female scheduled to undergo surgical drainage of Bartholin abscess. Spinal anesthesia was performed with bupivacaine and fentanyl. There were no perioperative adverse events reported. On postoperative day 1, the patient went to the emergency department describing bilateral weakness and pain of the lower extremities (LE). Lumbar magnetic resonance imaging showed increased gadolinium accumulation in the neural sheath at the level of the cauda equina tracts, consistent with the diagnosis of arachnoiditis and the diagnosis of cauda equina was established. The patient received the following emergent treatment: 75 mg pregabalin (oral) every 12 hours, 20 mg (8 drops) tramadol (oral) every 8 hours, and 4 mg dexamethasone (intravenous) every 6 hours. On postoperative day 4, the patient still experienced bilateral flaccid paraparesis (accentuated in the left side), neuropathic pain in low extremities, and left brachial monoparesis. Hence, dexamethasone was instantly replaced with 1 g methylprednisolone (intravenous) for 5 days. After completing 5 days of methylprednisolone, on postoperative day 9, the patient experienced less pain in left extremities, osteotendinous reflexes were slightly diminished, and she was able to walk with difficulty for 3 to 5 minutes. Greater mobility was evidenced, with right proximal and distal low extremities Medical Research Council Scale grades of 2 and 3 and left proximal and distal low extremities Medical Research Council Scale grades 1 and 2, respectively. Oral prednisone was restarted. Consequently, she was discharged home in stable conditions on postoperative day 25 with
Pargo Chasma and its relationship to global tectonics
NASA Technical Reports Server (NTRS)
Ghail, R. C.
Pargo Chasma was first identified on Pioneer Venus data as a 10,000 km long lineation extending from Atla Regio in the north terminating in the plains south of Phoebe Regio. More recent Magellan data have revealed this feature to be one of the longest chains of coronae so far identified on the planet. Stofan et al have identified 60 coronae and 2 related features associated with this chain; other estimates differ according to the classification scheme adopted, for example Head et al. identify only 29 coronae but 43 arachnoids in the same region. This highlights one of the major problems associated with the preliminary mapping of the Magellan data: there has been an emphasis on identifying particular features on Venus without a universally accepted scheme to classify those features. Nevertheless, Pargo Chasma is clearly identified as a major tectonic belt of global significance. Together with the Artemis-Atla-Beta tectonic zone and the Beta-Phoebe rift belt, Pargo Chasma defines a region on Venus with an unusually high concentration of tectonic and volcanic features. Thus, an understanding of the processes involved in the formation of Pargo Chasma may lend significant insight into the evolution of the region and the planet as a whole. I have produced a detailed 1 to 10 million scale map of Pargo Chasma and the surrounding area from preliminary USGS controlled mosaiced image maps of Venus constructed from Magellan data. In view of the problems highlighted above in relation the efforts already made at identifying a particular set of features I have mapped the region purely on the basis of the geomorphology visible in the magellan data without any attempt at identifying a particular set or class of features. Thus, the map produced distinguishes between areas of different brightness and texture. This has the advantage of highlighting the tectonic fabric of Pargo Chasma and clearly illustrates the close inter-relationship between individual coronae and the surrounding
Desmoplakin II expression is not restricted to stratified epithelia.
Angst, B D; Nilles, L A; Green, K J
Desmosomes are major intercellular junctions found in association with intermediate filaments in epithelial, cardiac and arachnoidal tissue. Desmoplakins I and II (DPI and II) are highly related proteins localized in the innermost part of the desmosomal plaque and are candidates for linking intermediate filaments (IF) to the desmosomal complex. While investigators agree that DPI is present in all epithelia, they disagree on the distribution of DPII. Some have reported DPII to be restricted to stratified tissue and have furthermore suggested that the expression of DPII may be linked to stratification. We have compared the expression of DPI and II at the mRNA and protein levels in cell lines derived from simple, transitional and stratified epithelia. Northern blot analysis revealed DPI and II mRNA to be present in all cell lines as well as simple and stratified epithelial tissues. However, DPII mRNA could not be detected in cardiac muscle tissue. Immunoblotting and immunoprecipitation demonstrated the presence of DPI and II in all cell lines at the whole-cell protein level as well as in association with cytoskeletal fractions. Immunofluorescence staining was used to correlate the biochemical findings with the localization of DPI and II. While most cell lines exhibited typical intercellular and in many cases cytoplasmic DP staining, T24 cells exhibited predominantly diffuse and dotty cytoplasmic staining. In addition, we investigated whether changes in DPI and II expression occurred following calcium-induced cell contact formation and stratification in the human pharyngeal cell line, FaDu. No significant changes in mRNA or whole-cell protein levels were observed during a period of 5 days following the calcium switch. However, immunoblotting revealed a significant increase in DPI and II levels in the insoluble protein pool during desmosome formation. These observations indicated a possible recruitment of soluble DPI/II into an insoluble pool after induction of
Quantifying response to intracranial pressure normalization in idiopathic intracranial hypertension via dynamic neuroimaging.
Lublinsky, Svetlana; Kesler, Anat; Friedman, Alon; Horev, Anat; Shelef, Ilan
Idiopathic intracranial hypertension (IIH) is characterized by elevated intracranial pressure without a clear cause. To investigate dynamic imaging findings in IIH and their relation to mechanisms underlying intracranial pressure normalization. Prospective. Eighteen IIH patients and 30 healthy controls. T 1 -weighted, venography, fluid attenuation inversion recovery, and apparent diffusion coefficients were acquired on 1.5T scanner. The dural sinus was measured before and after lumbar puncture (LP). The degree of sinus occlusion was evaluated, based on 95% confidence intervals of controls. We studied a number of neuroimaging biomarkers associated with IIH (sinus occlusion; optic nerve; distribution of cerebrospinal fluid into the subarachnoid space, sulci and lateral ventricles (LVs); Meckel's caves; arachnoid granulation; pituitary and choroid plexus), before and after LP, using a set of specially developed quantification techniques. Relationships among various biomarkers were investigated (Pearson correlation coefficient) and linked to long-term disease outcomes (logistic regression). The t-test and the Wilcoxon rank test were used to compare between controls and before and after LP data. As a result of LP, the following were found to be in good accordance with the opening pressure: relative compression of cerebrospinal fluid (R = -0.857, P < 0.001) and brain volumes (R = -0.576, P = 0.012), LV expansion (R = 0.772, P < 0.001) and venous volume (R = 0.696, P = 0.001), enlargement of the pituitary (R = 0.640, P = 0.023), and shrinkage of subarachnoid space (R = -0.887, P < 0.001). The only parameter that had an impact on long-term prognosis was cross-sectional size of supplemental drainage veins after LP (sensitivity of 92%, specificity of 20%, and area under the curve of 0.845, P < 0.001). We present an approach for quantitative characterization of the intracranial venous system and its implementation as a diagnostic assistance
Endoscopic intracranial surgery enhanced by electromagnetic-guided neuronavigation in children.
Hermann, Elvis J; Esmaeilzadeh, Majid; Ertl, Philipp; Polemikos, Manolis; Raab, Peter; Krauss, Joachim K
Navigated intracranial endoscopy with conventional technique usually requires sharp head fixation. In children, especially in those younger than 1 year of age and in older children with thin skulls due to chronic hydrocephalus, sharp head fixation is not possible. Here, we studied the feasibility, safety, and accuracy of electromagnetic (EM)-navigated endoscopy in a series of children, obviating the need of sharp head fixation. Seventeen children (ten boys, seven girls) between 12 days and 16.8 years (mean age 4.3 years; median 14 months) underwent EM-navigated intracranial endoscopic surgery based on 3D MR imaging of the head. Inclusion criteria for the study were intraventricular cysts, arachnoid cysts, aqueduct stenosis for endoscopic third ventriculostomy (ETV) with distorted ventricular anatomy, the need of biopsy in intraventricular tumors, and multiloculated hydrocephalus. A total of 22 endoscopic procedures were performed. Patients were registered for navigation by surface rendering in the supine position. After confirming accuracy, they were repositioned for endoscopic surgery with the head fixed slightly on a horseshoe headholder. EM navigation was performed using a flexible stylet introduced into the working channel of a rigid endoscope. Neuronavigation accuracy was checked for deviations measured in millimeters on screenshots after the referencing procedure and during surgery in the coronal (z = vertical), axial (x = mediolateral), and sagittal (y = anteroposterior) planes. EM-navigated endoscopy was feasible and safe. In all 17 patients, the aim of endoscopic surgery was achieved, except in one case in which a hemorrhage occurred, blurring visibility, and we proceeded with open surgery without complications for the patient. Navigation accuracy for extracranial markers such as the tragus, bregma, and nasion ranged between 1 and 2.5 mm. Accuracy for fixed anatomical structures like the optic nerve or the carotid artery varied between 2 and 4
A spreading drop model for plumes on Venus
NASA Astrophysics Data System (ADS)
Koch, D. M.
deformation (such as arachnoids), and end with coronae (with mostly concentric deformation). The model predicts that the highlands evolve on a timescale of order 10 Ma, and the smaller-scale features evolve in a 100 Ma timescale.
A novel method for stereotactic, endoscope-assisted transtentorial placement of a shunt catheter into symptomatic posterior fossa cysts.
Turner, Michael S; Nguyen, Ha Son; Payner, Troy D; Cohen-Gadol, Aaron A
Posterior fossa cysts are usually divided into Dandy-Walker malformations, arachnoid cysts, and isolated and/or trapped fourth ventricles. Shunt placement is a mainstay treatment for decompression of these fluid collections when their expansion becomes symptomatic. Although several techniques to drain symptomatic posterior fossa cysts have been described, each method carries its own advantages and disadvantages. This article describes an alternative technique. In 10 patients, the authors used an alternative technique involving stereotactic and endoscopic methods to place a catheter in symptomatic posterior fossa cysts across the tentorium. Discussion of these cases is included, along with a review of various approaches to shunt placement in this region and recommendations regarding the proposed technique. No patient suffered intracranial hemorrhage related to the procedure and catheter implantation. All 3 patients who underwent placement of a new transtentorial cystoperitoneal shunt and a new ventriculoperitoneal shunt did not suffer any postoperative complication; a decrease in the size of their posterior fossa cysts was evident on CT scans obtained during the 1st postoperative day. Follow-up CT scans demonstrated either stable findings or further interval decrease in the size of their cysts. In 1 patient, the postoperative head CT demonstrated that the transtentorial catheter terminated posterior to the right parietal occipital region without entering the retrocerebellar cyst. This patient underwent a repeat operation for proximal shunt revision, resulting in an acceptable catheter implantation. The patient in Case 8 suffered from a shunt infection and subsequently underwent hardware removal and aqueductoplasty with stent placement. The patient in Case 9 demonstrated a slight increase in fourth ventricle size and was returned to the operating room. Exploration revealed a kink in the tubing connecting the distal limb of the Y connector to the valve. The Y
[Medico-economic assessment of the Pontoise Hospital stroke unit].
Yekhlef, F; Decup, D; Niclot, P; Servan, J; Descombes, S; Richecoeur, J; Ollivier, A
Annually, approximately 120,000 people in France have a stroke. Various controlled studies have pointed out the benefits of treatment in a stroke unit (SU). The objective of this study was to evaluate, from a medical point of view, the economic impact of the Pontoise Hospital SU. Based on the national cost study (NCS [étude nationale des coûts: ENC]) we analyzed data of five diagnosis related groups (DRG) which have a principle diagnosis in relation with stroke. This work was limited to strokes and transient ischemic events in adults and excluded sub-arachnoid hemorrhage. Medical and economic parameters were collected over the period from January to October 2006 and compared with those of the same period in 2005, that is to say before the opening of the SU. Three hundred and twenty-three hospital stays occurred between January 1st and October 31st, 2006 and 216 during the same time period before the opening of the SU, an increase of approximately 50% of all stroke-related admissions in our hospital. The number of stays carried out in the neurology unit increased by 29%. There was no significant difference between the two periods regarding age (median 69 versus 70 years) and sex- ratio. Average length of stay (ALS) was the same (9 days). There were no significant differences concerning the death rate (5.6% versus 6.2%) and that of discharge to home (44.6% versus 44.4%). The cost by stay in 2006 was 3534 euros [median; min 664-max 57,542] versus 3541 euros in 2005 [681-35,149] (p=0.57). Analysis by DRG highlighted an increase in the cost for serious strokes, cerebral infarctions and hemorrhages. For transitory ischemic events, the cost and the ALS decreased. After the opening of the SU, there was an increase in the activity without an increase in the total cost. This could be related in part to the limited means allocated to the stroke unit at its opening (in particular medical staff). The NCS can be used to evaluate the activity of a stroke unit. This work could
Protection of cortex by overlying meninges tissue during dynamic indentation of the adolescent brain.
MacManus, David B; Pierrat, Baptiste; Murphy, Jeremiah G; Gilchrist, Michael D
Traumatic brain injury (TBI) has become a recent focus of biomedical research with a growing international effort targeting material characterization of brain tissue and simulations of trauma using computer models of the head and brain to try to elucidate the mechanisms and pathogenesis of TBI. The meninges, a collagenous protective tri-layer, which encloses the entire brain and spinal cord has been largely overlooked in these material characterization studies. This has resulted in a lack of accurate constitutive data for the cranial meninges, particularly under dynamic conditions such as those experienced during head impacts. The work presented here addresses this lack of data by providing for the first time, in situ large deformation material properties of the porcine dura-arachnoid mater composite under dynamic indentation. It is demonstrated that this tissue is substantially stiffer (shear modulus, μ=19.10±8.55kPa) and relaxes at a slower rate (τ 1 =0.034±0.008s, τ 2 =0.336±0.077s) than the underlying brain tissue (μ=6.97±2.26kPa, τ 1 =0.021±0.007s, τ 2 =0.199±0.036s), reducing the magnitudes of stress by 250% and 65% for strains that arise during indentation-type deformations in adolescent brains. We present the first mechanical analysis of the protective capacity of the cranial meninges using in situ micro-indentation techniques. Force-relaxation tests are performed on in situ meninges and cortex tissue, under large strain dynamic micro-indentation. A quasi-linear viscoelastic model is used subsequently, providing time-dependent mechanical properties of these neural tissues under loading conditions comparable to what is experienced in TBI. The reported data highlights the large differences in mechanical properties between these two tissues. Finite element simulations of the indentation experiments are also performed to investigate the protective capacity of the meninges. These simulations show that the meninges protect the underlying brain tissue
Comparison of the global gene expression of choroid plexus and meninges and associated vasculature under control conditions and after pronounced hyperthermia or amphetamine toxicity.
Bowyer, John F; Patterson, Tucker A; Saini, Upasana T; Hanig, Joseph P; Thomas, Monzy; Camacho, Luísa; George, Nysia I; Chen, James J
The meninges (arachnoid and pial membranes) and associated vasculature (MAV) and choroid plexus are important in maintaining cerebrospinal fluid (CSF) generation and flow. MAV vasculature was previously observed to be adversely affected by environmentally-induced hyperthermia (EIH) and more so by a neurotoxic amphetamine (AMPH) exposure. Herein, microarray and RT-PCR analysis was used to compare the gene expression profiles between choroid plexus and MAV under control conditions and at 3 hours and 1 day after EIH or AMPH exposure. Since AMPH and EIH are so disruptive to vasculature, genes related to vasculature integrity and function were of interest. Our data shows that, under control conditions, many of the genes with relatively high expression in both the MAV and choroid plexus are also abundant in many epithelial tissues. These genes function in transport of water, ions, and solutes, and likely play a role in CSF regulation. Most genes that help form the blood-brain barrier (BBB) and tight junctions were also highly expressed in MAV but not in choroid plexus. In MAV, exposure to EIH and more so to AMPH decreased the expression of BBB-related genes such as Sox18, Ocln, and Cldn5, but they were much less affected in the choroid plexus. There was a correlation between the genes related to reactive oxidative stress and damage that were significantly altered in the MAV and choroid plexus after either EIH or AMPH. However, AMPH (at 3 hr) significantly affected about 5 times as many genes as EIH in the MAV, while in the choroid plexus EIH affected more genes than AMPH. Several unique genes that are not specifically related to vascular damage increased to a much greater extent after AMPH compared to EIH in the MAV (Lbp, Reg3a, Reg3b, Slc15a1, Sct and Fst) and choroid plexus (Bmp4, Dio2 and Lbp). Our study indicates that the disruption of choroid plexus function and damage produced by AMPH and EIH is significant, but the changes may not be as pronounced as they are in
Scanning electron microscopy of chronically implanted intracortical microelectrode arrays in non-human primates
NASA Astrophysics Data System (ADS)
Barrese, James C.; Aceros, Juan; Donoghue, John P.
Objective. Signal attenuation is a major problem facing intracortical sensors for chronic neuroprosthetic applications. Many studies suggest that failure is due to gliosis around the electrode tips, however, mechanical and material causes of failure are often overlooked. The purpose of this study was to investigate the factors contributing to progressive signal decline by using scanning electron microscopy (SEM) to visualize structural changes in chronically implanted arrays and histology to examine the tissue response at corresponding implant sites. Approach. We examined eight chronically implanted intracortical microelectrode arrays (MEAs) explanted from non-human primates at times ranging from 37 to 1051 days post-implant. We used SEM, in vivo neural recordings, and histology (GFAP, Iba-1, NeuN). Three MEAs that were never implanted were also imaged as controls. Main results. SEM revealed progressive corrosion of the platinum electrode tips and changes to the underlying silicon. The parylene insulation was prone to cracking and delamination, and in some instances the silicone elastomer also delaminated from the edges of the MEA. Substantial tissue encapsulation was observed and was often seen growing into defects in the platinum and parylene. These material defects became more common as the time in vivo increased. Histology at 37 and 1051 days post-implant showed gliosis, disruption of normal cortical architecture with minimal neuronal loss, and high Iba-1 reactivity, especially within the arachnoid and dura. Electrode tracts were either absent or barely visible in the cortex at 1051 days, but were seen in the fibrotic encapsulation material suggesting that the MEAs were lifted out of the brain. Neural recordings showed a progressive drop in impedance, signal amplitude, and viable channels over time. Significance. These results provide evidence that signal loss in MEAs is truly multifactorial. Gliosis occurs in the first few months after implantation but does
Scanning electron microscopy of chronically implanted intracortical microelectrode arrays in non-human primates
Barrese, James C; Aceros, Juan; Donoghue, John P
Objective Signal attenuation is a major problem facing intracortical sensors for chronic neuroprosthetic applications. Many studies suggest that failure is due to gliosis around the electrode tips, however, mechanical and material causes of failure are often overlooked. The purpose of this study was to investigate the factors contributing to progressive signal decline by using scanning electron microscopy (SEM) to visualize structural changes in chronically implanted arrays and histology to examine the tissue response at corresponding implant sites. Approach We examined eight chronically implanted intracortical microelectrode arrays (MEAs) explanted from non-human primates at times ranging from 37 to 1051 days post-implant. We used SEM, in vivo neural recordings, and histology (GFAP, Iba-1, NeuN). Three MEAs that were never implanted were also imaged as controls. Main results SEM revealed progressive corrosion of the platinum electrode tips and changes to the underlying silicon. The parylene insulation was prone to cracking and delamination, and in some instances the silicone elastomer also delaminated from the edges of the MEA. Substantial tissue encapsulation was observed and was often seen growing into defects in the platinum and parylene. These material defects became more common as the time in vivo increased. Histology at 37 and 1051 days post-implant showed gliosis, disruption of normal cortical architecture with minimal neuronal loss, and high Iba-1 reactivity, especially within the arachnoid and dura. Electrode tracts were either absent or barely visible in the cortex at 1051 days, but were seen in the fibrotic encapsulation material suggesting that the MEAs were lifted out of the brain. Neural recordings showed a progressive drop in impedance, signal amplitude, and viable channels over time. Significance These results provide evidence that signal loss in MEAs is truly multifactorial. Gliosis occurs in the first few months after implantation but does not
Scanning electron microscopy of chronically implanted intracortical microelectrode arrays in non-human primates.
Barrese, James C; Aceros, Juan; Donoghue, John P
Signal attenuation is a major problem facing intracortical sensors for chronic neuroprosthetic applications. Many studies suggest that failure is due to gliosis around the electrode tips, however, mechanical and material causes of failure are often overlooked. The purpose of this study was to investigate the factors contributing to progressive signal decline by using scanning electron microscopy (SEM) to visualize structural changes in chronically implanted arrays and histology to examine the tissue response at corresponding implant sites. We examined eight chronically implanted intracortical microelectrode arrays (MEAs) explanted from non-human primates at times ranging from 37 to 1051 days post-implant. We used SEM, in vivo neural recordings, and histology (GFAP, Iba-1, NeuN). Three MEAs that were never implanted were also imaged as controls. SEM revealed progressive corrosion of the platinum electrode tips and changes to the underlying silicon. The parylene insulation was prone to cracking and delamination, and in some instances the silicone elastomer also delaminated from the edges of the MEA. Substantial tissue encapsulation was observed and was often seen growing into defects in the platinum and parylene. These material defects became more common as the time in vivo increased. Histology at 37 and 1051 days post-implant showed gliosis, disruption of normal cortical architecture with minimal neuronal loss, and high Iba-1 reactivity, especially within the arachnoid and dura. Electrode tracts were either absent or barely visible in the cortex at 1051 days, but were seen in the fibrotic encapsulation material suggesting that the MEAs were lifted out of the brain. Neural recordings showed a progressive drop in impedance, signal amplitude, and viable channels over time. These results provide evidence that signal loss in MEAs is truly multifactorial. Gliosis occurs in the first few months after implantation but does not prevent useful recordings for several years
Comparison of the global gene expression of choroid plexus and meninges and associated vasculature under control conditions and after pronounced hyperthermia or amphetamine toxicity
Background The meninges (arachnoid and pial membranes) and associated vasculature (MAV) and choroid plexus are important in maintaining cerebrospinal fluid (CSF) generation and flow. MAV vasculature was previously observed to be adversely affected by environmentally-induced hyperthermia (EIH) and more so by a neurotoxic amphetamine (AMPH) exposure. Herein, microarray and RT-PCR analysis was used to compare the gene expression profiles between choroid plexus and MAV under control conditions and at 3 hours and 1 day after EIH or AMPH exposure. Since AMPH and EIH are so disruptive to vasculature, genes related to vasculature integrity and function were of interest. Results Our data shows that, under control conditions, many of the genes with relatively high expression in both the MAV and choroid plexus are also abundant in many epithelial tissues. These genes function in transport of water, ions, and solutes, and likely play a role in CSF regulation. Most genes that help form the blood–brain barrier (BBB) and tight junctions were also highly expressed in MAV but not in choroid plexus. In MAV, exposure to EIH and more so to AMPH decreased the expression of BBB-related genes such as Sox18, Ocln, and Cldn5, but they were much less affected in the choroid plexus. There was a correlation between the genes related to reactive oxidative stress and damage that were significantly altered in the MAV and choroid plexus after either EIH or AMPH. However, AMPH (at 3 hr) significantly affected about 5 times as many genes as EIH in the MAV, while in the choroid plexus EIH affected more genes than AMPH. Several unique genes that are not specifically related to vascular damage increased to a much greater extent after AMPH compared to EIH in the MAV (Lbp, Reg3a, Reg3b, Slc15a1, Sct and Fst) and choroid plexus (Bmp4, Dio2 and Lbp). Conclusions Our study indicates that the disruption of choroid plexus function and damage produced by AMPH and EIH is significant, but the changes
Does Spinal Block Through Tattooed Skin Cause Histological Changes in Nervous Tissue and Meninges?: An Experimental Model in Rabbits.
Ferraz, Isabela Leite; Barros, Guilherme Antônio Moreira de; Ferreira Neto, Patrícia Gomes; Solanki, Daneshivari; Marques, Mariângela Alencar; Machado, Vânia Maria de Vasconcelos; Cabral, Lucas Wynne; Lima, Rodrigo Moreira E; Vianna, Pedro Thadeu Galvão; Navarro, Lais Helena Camacho; Ganen, Eliana Marisa
Although there is no documented evidence that tattoo pigments can cause neurological complications, the implications of performing neuraxial anesthesia through tattooed skin are unknown. In this study, we aimed to assess whether spinal puncture performed through tattooed skin of rabbits determines changes over the spinal cord and meninges. In addition, we sought to evaluate the presence of ink fragments entrapped in spinal needles. Thirty-six young male adult rabbits, each weighing between 3400 and 3900 g and having a spine length between 38.5 and 39 cm, were divided by lot into 3 groups as follows: GI, spinal puncture through tattooed skin; GII, spinal puncture through tattooed skin and saline injection; and GIII, spinal puncture through skin free of tattoo and saline injection. After intravenous anesthesia with ketamine and xylazine, the subarachnoid space was punctured at S1-S2 under ultrasound guidance with a 22-gauge 2½ Quincke needle. Animals in GII and GIII received 5 μL/cm of spinal length (0.2 mL) of saline intrathecally. In GI, the needle tip was placed into the yellow ligament, and no solution was injected into the intrathecal space; after tattooed skin puncture, 1 mL of saline was injected through the needle over a histological slide to prepare a smear that was dyed by the Giemsa method to enable tissue identification if present. All animals remained in captivity for 21 days under medical observation and were killed by decapitation. The lumbosacral spinal cord portion was removed for histological analysis using hematoxylin-eosin stain. None of the animals had impaired motor function or decreased nociception during the period of clinical observation. None of the animals from the control group (GIII) showed signs of injuries to meninges. In GII, however, 4 animals presented with signs of meningeal injury. The main histological changes observed were focal areas of perivascular lymphoplasmacyte infiltration in the pia mater and arachnoid. There was no
[Structural CNS abnormalities responsible for coincidental occurrence of endocrine disorders, epilepsy and psychoneurologic disorders in children and adolescents].
Starzyk, Jerzy; Kwiatkowski, Stanisław; Kaciński, Marek; Kroczka, Sławomir; Wójcik, Małgorzata
suprasellar arachnoid cyst (7 patients), septo-optic dysplasia (8 patients), craniopharyngioma (15 patients), glioma of the optic chiasm in neurofibromatosis type 1 (NF-1) (12 patients). There were no endocrine disorders in any of the ten patients with hamartoma of the hypothalamus and CPP. Endocrine and/ or neurological disorders did not resolve or were progressive after neurosurgery. Of 42 patients, a group of seven children representative for individual disorders was selected. In those patients, the etiology of both endocrine disorders, epilepsy and neuropsychiatric disorders was suspected to be common. 1. Various structural CNS abnormalities are the cause of concomitant epilepsy and endocrinopathy, although in some cases a direct impact of a genetic factor on the occurrence of both disorders or a mere coincidence cannot be ruled out. 2. Psychoneurological disorders usually precede the onset of endocrinopathy. 3. For this reason, MR or CT CNS imaging should be performed in any case of central neurological disorders, disorders of behavior, epilepsy, obsessive-compulsive syndrome, but also in patients with delayed psycho-motor development, delayed or accelerated growth and pubertal development. All of the above-mentioned manifestations may be symptoms of structural CNS abnormalities and their early treatment determines the child's future.
Resuscitation from severe hemorrhagic shock after traumatic brain injury using saline, shed blood, or a blood substitute.
Gibson, Jeffrey B; Maxwell, Robert A; Schweitzer, John B; Fabian, Timothy C; Proctor, Kenneth G
The original purpose of this study was to compare initial resuscitation of hemorrhagic hypotension after traumatic brain injury (TBI) with saline and shed blood. Based on those results, the protocol was modified and saline was compared to a blood substitute, diaspirin cross-linked hemoglobin (DCLHb). Two series of experiments were performed in anesthetized and mechanically ventilated (FiO2 = 0.4) pigs (35-45 kg). In Series 1, fluid percussion TBI (6-8 ATM) was followed by a 30% hemorrhage. At 120 min post-TBI, initial resuscitation consisted of either shed blood (n = 7) or a bolus of 3x shed blood volume as saline (n = 13). Saline supplements were then administered to all pigs to maintain a systolic arterial blood pressure (SAP) of >100 mmHg and a heart rate (HR) of <110 beats/min. In Series 2, TBI (4-5 ATM) was followed by a 35% hemorrhage. At 60 min post-TBI, initial resuscitation consisted of either 500 mL of DCLHb (n = 6) or 500 mL of saline (n = 5). This was followed by saline supplements to all pigs to maintain a SAP of >100 mmHg and a HR of <110 beats/min. In Series 1, most systemic markers of resuscitation (e.g., SAP, HR, cardiac output, filling pressures, lactate, etc.) were normalized, but there were 0/7 vs. 5/13 deaths within 5 h (P = 0.058) with blood vs. saline. At constant arterial O2 saturation (SaO2), mixed venous O2 saturation (SvO2), cerebral perfusion pressure (CPP), and cerebral venous O2 saturation (ScvO2) were all higher, intracranial pressure (ICP) was lower, and CO2 reactivity was preserved with blood vs. saline (all P < 0.05). In Series 2, SAP, ICP, CPP, and lactate were higher with DCLHb vs. saline (all P< 0.05). Cardiac output was lower even though filling pressure was markedly elevated with DCLHb vs. saline (both P< 0.05). Neither SvO2 nor cerebrovascular CO2 reactivity were improved, and ScvO2 was lower with DCLHb vs. saline (P < 0.05). All survived at least 72 h with neuropathologic changes that included sub-arachnoid hemorrhage
Pulsed laser-induced liquid jet: evolution from shock/bubble interaction to neurosurgical application
NASA Astrophysics Data System (ADS)
Nakagawa, A.; Kumabe, T.; Ogawa, Y.; Hirano, T.; Kawaguchi, T.; Ohtani, K.; Nakano, T.; Sato, C.; Yamada, M.; Washio, T.; Arafune, T.; Teppei, T.; Atsushi, K.; Satomi, S.; Takayama, K.; Tominaga, T.
fine perforating vessel involvement, and cerebrovascular disease (1 arteriovenous malformation and 2 intracerebral hemorrhages) in 3 patients. Precise dissection and mass reduction of the tumor were obtained in all tumor cases except for one chordoma with significant fibrosis. Small arteries down to 100 μ m were preserved, allowing subsequent microsurgical devascularization. Veins were also preserved occasionally. The arachnoid membrane and the tumor capsule were resistant to the LILJ except for one case with prolonged exposure. No complications related to use of the LILJ system were observed. No disturbance of the surgical field by splashing, aerosol, or dissemination of pathological tissue occurred with placement of the optimal suction system. The Ho:YAG LILJ system enhances the advantages of commercialized pressure-driven continuous liquid jet instrumentation in terms of small vessel preservation and accessibility in confined spaces for minimally invasive neurosurgery, and solves some of the drawbacks involved with excessive liquid use and size.
The biological significance of brain barrier mechanisms: help or hindrance in drug delivery to the central nervous system?
Saunders, Norman R.; Habgood, Mark D.; Møllgård, Kjeld; Dziegielewska, Katarzyna M.
Barrier mechanisms in the brain are important for its normal functioning and development. Stability of the brain’s internal environment, particularly with respect to its ionic composition, is a prerequisite for the fundamental basis of its function, namely transmission of nerve impulses. In addition, the appropriate and controlled supply of a wide range of nutrients such as glucose, amino acids, monocarboxylates, and vitamins is also essential for normal development and function. These are all cellular functions across the interfaces that separate the brain from the rest of the internal environment of the body. An essential morphological component of all but one of the barriers is the presence of specialized intercellular tight junctions between the cells comprising the interface: endothelial cells in the blood-brain barrier itself, cells of the arachnoid membrane, choroid plexus epithelial cells, and tanycytes (specialized glial cells) in the circumventricular organs. In the ependyma lining the cerebral ventricles in the adult brain, the cells are joined by gap junctions, which are not restrictive for intercellular movement of molecules. But in the developing brain, the forerunners of these cells form the neuroepithelium, which restricts exchange of all but the smallest molecules between cerebrospinal fluid and brain interstitial fluid because of the presence of strap junctions between the cells. The intercellular junctions in all these interfaces are the physical basis for their barrier properties. In the blood-brain barrier proper, this is combined with a paucity of vesicular transport that is a characteristic of other vascular beds. Without such a diffusional restrain, the cellular transport mechanisms in the barrier interfaces would be ineffective. Superimposed on these physical structures are physiological mechanisms as the cells of the interfaces contain various metabolic transporters and efflux pumps, often ATP-binding cassette (ABC) transporters, that
Starling resistors, autoregulation of cerebral perfusion and the pathogenesis of idiopathic intracranial hypertension.
DE Simone, Roberto; Ranieri, Angelo; Bonavita, Vincenzo
Two critical functions for the control of intracranial fluids dynamics are carried on the venous side of the perfusion circuit: the first is the avoidance of cortical veins collapse during the physiological increases of cerebrospinal fluid (CSF) pressure in which they are immersed. The second, is the generation of an abrupt venous pressure drop at the confluence of the cortical veins with the dural sinuses that is required to allow a CSF outflow rate balanced with its production. There is evidence that both of these effects are ensured by a Starling resistor mechanism (a fluid dynamic construct that governs the flow in collapsible tubes exposed to variable external pressure) acting at the confluence of cortical veins in the dural sinus. This implies that, in normal circumstances of perfusion balance, a certain degree of venous collapse physiologically occurs at the distal end of the cortical vein. This is passively modulated by the transmural pressure of the venous wall (i.e. the difference between internal blood pressure and external CSF pressure). The mechanism provides that the blood pressure of the cortical vein upstream the collapsed segment is dynamically maintained a few mmHg higher than the CSF pressure, so as to prevent their collapse during the large physiological fluctuations of the intracranial pressure. Moreover, the partial collapse of the vein confluence also generates a sharp pressure drop of the blood entering into the sinus. The CSF is drained in dural sinus through arachnoid villi proportionally to its pressure gradient with the sinus blood. The venous pressure drop between cortical veins and dural sinus is therefore needed to ensure that the CSF can leave the cranio-spinal space with the same speed with which it is produced, without having to reach a too high pressure, which would compress the cortical veins. Notably, the mechanism requires that the walls of the dural sinuses are rigid enough to avoid the collapse under the external
Chiari I malformation with and without basilar invagination: a comparative study.
Chiari I malformation is the most common craniocervical malformation. Its combination with basilar invagination in a significant proportion of patients is well established. This study presents surgical results for patients with Chiari I malformation with and without additional basilar invagination. Three hundred twenty-three patients underwent 350 operations between 1985 and 2013 (mean age 43 ± 16 years, mean history of symptoms 64 ± 94 months). The clinical courses were documented with a score system for individual neurological symptoms for short-term results after 3 and 12 months. Long-term outcomes were analyzed with Kaplan-Meier statistics. The mean follow-up was 53 ± 58 months (the means are expressed ± SD). Patients with (n = 46) or without (n = 277) basilar invagination in addition to Chiari I malformation were identified. Patients with invagination were separated into groups: those with (n = 31) and without (n = 15) ventral compression by the odontoid in the foramen magnum. Of the 350 operations, 313 dealt with the craniospinal pathology, 28 surgeries were undertaken for degenerative diseases of the cervical spine, 3 were performed for hydrocephalus, and 6 syrinx catheters were removed for cord tethering. All craniospinal operations included a foramen magnum decompression with arachnoid dissection, opening of the fourth ventricle, and a duraplasty. In patients without invagination, craniospinal instability was detected in 4 individuals, who required additional craniospinal fusion. In patients with invagination but without ventral compression, no stabilization was added to the decompression. In all patients with ventral compression, craniospinal stabilization was performed with the foramen magnum decompression, except for 4 patients with mild ventral compression early in the series who underwent posterior decompression only. Among those with ventral compression, 9 patients with caudal cranial nerve dysfunctions underwent a combination of transoral
[Results of surgical treatment of syringomyelia associated with Chiari 1 malformation. An analysis of 125 cases].
Zuev, A A; Pedyash, N V; Epifanov, D S; Kostenko, G V
The rate of Chiari malformation (CM) in a population ranges from 3 to 8 per 100,000 population. In 62-80% of cases, CM is accompanied by the development of syringomyelia (SM) at various levels. The clinical picture in these patients is a combination of CM and SM manifestations; however, SM symptoms often prevail, which creates some problems in the diagnosis of the disease and in the choice of optimal treatment. On the basis of our own experience of surgical interventions, we aimed to clarify the indications for surgical treatment of SM associated with CM and to determine the optimal amount of surgery and the criteria for evaluation of treatment outcomes. Two hundred twenty five patients with a combination of syringomyelia and Chiari 1 malformation were examined in the period from 2011 to February 2015. Of them, 125 patients were operated on. The mean age of the operated patients was 56±8 years. The mean time from the appearance of the first signs of the disease to surgery was 75±82 months. All operations were performed by a single surgeon. The operations were carried out in the half-sitting (89.6%) or prone (10.4%) position. The operation included sparing suboccipital craniectomy, C1 arch resection, recovery of the cerebrospinal fluid (CSF) circulation along the posterior surface of the cerebellum, and reconstruction of the dura mater in the craniovertebral junction region. Exploration of the arachnoid mater of the cisterna magna after dura opening revealed no arachnopathy in 78 (62.4%) patients (Chiari 0 malformation according to Klekamp). The type 1 arachnopathy (by Klekamp) was detected in 31 patients (24.8%), and the type 2 arachnopathy was observed in 16 (12.8%). The condition of 109 (88%) patients was evaluated one year after the surgery. Sixty one (56%) patients had partial or complete regression of preoperative neurological symptoms. The disease stopped progressing in 44 patients (40%). The disease was progressing in 4 (3.7%) patients. No recurrence of a
Global Stratigraphy of Venus: Analysis of a Random Sample of Thirty-Six Test Areas
NASA Technical Reports Server (NTRS)
Basilevsky, Alexander T.; Head, James W., III
The age relations between 36 impact craters with dark paraboloids and other geologic units and structures at these localities have been studied through photogeologic analysis of Magellan SAR images of the surface of Venus. Geologic settings in all 36 sites, about 1000 x 1000 km each, could be characterized using only 10 different terrain units and six types of structures. These units and structures form a major stratigraphic and geologic sequence (from oldest to youngest): (1) tessera terrain; (2) densely fractured terrains associated with coronae and in the form of remnants among plains; (3) fractured and ridged plains and ridge belts; (4) plains with wrinkle ridges; (5) ridges associated with coronae annulae and ridges of arachnoid annulae which are contemporary with wrinkle ridges of the ridged plains; (6) smooth and lobate plains; (7) fractures of coronae annulae, and fractures not related to coronae annulae, which disrupt ridged and smooth plains; (8) rift-associated fractures; and (9) craters with associated dark paraboloids, which represent the youngest 1O% of the Venus impact crater population (Campbell et al.), and are on top of all volcanic and tectonic units except the youngest episodes of rift-associated fracturing and volcanism; surficial streaks and patches are approximately contemporary with dark-paraboloid craters. Mapping of such units and structures in 36 randomly distributed large regions (each approximately 10(exp 6) sq km) shows evidence for a distinctive regional and global stratigraphic and geologic sequence. On the basis of this sequence we have developed a model that illustrates several major themes in the history of Venus. Most of the history of Venus (that of its first 80% or so) is not preserved in the surface geomorphological record. The major deformation associated with tessera formation in the period sometime between 0.5-1.0 b.y. ago (Ivanov and Basilevsky) is the earliest event detected. In the terminal stages of tessera fon
Aralia elata var. mandshurica (Rupr. & Maxim.) J.Wen: An overview of pharmacological studies.
Shikov, Alexander N; Pozharitskaya, Olga N; Makarov, Valery G
activity, inhibit endoplasmic reticulum stress-associated apoptosis markers (GRP78, CHOP, Caspase-12, and JNK), and increase phosphorylation of STAT3 and Bcl2/Bax ratio; they also show cytotoxic activities against some tumor cell lines; affect NF-κB and PPARs activities; and regulate biosynthesis of pro-inflammatory cytokines and inflammation-related protein expression, tissue respiration, and oxygen consumption. In healthy subjects, Aralia increases mental performance, working capacity, and endurance of movement. Numerous clinical trials have shown the efficiency of Aralia preparations in patients with traumatic brain injury (accompanied with asthenic syndrome and neurotic reactions, depression, neurasthenia, and psychasthenia), neurological diseases (accompanied with astheno-depressive and astheno-hypochondriasis syndromes), myasthenia syndrome (accompanied with chronic post-influenza arachnoiditis), and arterial hypotension. Aralia tincture and "Saparal" are useful as antiviral remedies. Radioprotective properties of Aralia have been reported in pregnant women. Synergistic antiobesity effect was reported for the combination of A. mandshurica and Engelhardtia chrysolepis extracts and antidiabetic effect for the combination of Aralia and glipizide. Promising stress-relieving effects of Aralia are reported for professionals whose work requires a high level of attention. Its proposed ability to moderate stress-induced damage and dysfunction in the cardiovascular tissue might make Aralia the adaptogen of choice among patients with higher risk for cardiovascular diseases. Because Aralia extract administration appears to affect plasma glucose level and hepatic lipid accumulation and ameliorate hyperinsulinemia, it might also provide benefits and be the adaptogen of choice for patients with obesity and diabetes. This review describes the considerable diversity of pharmacological effects of A. elata reported in numerous studies carried out in the former USSR and other countries
Diffusion-weighted MR of the brain: methodology and clinical application.
Mascalchi, Mario; Filippi, Massimo; Floris, Roberto; Fonda, Claudio; Gasparotti, Roberto; Villari, Natale
tensor, has a fundamental role in the assessment of brain maturation and of white matter diseases in the fetus, in the neonate and in the child. Diffusion MR imaging enables a better characterisation of the lesions demonstrated by conventional MR imaging, for instance in the hypoxic-ischaemic encephalopathy, in infections and in the inherited metabolic diseases, and is particularly important for the longitudinal evaluation of these conditions. Diffusion-weighted MR imaging has an established role in the differential diagnosis between brain abscess and cystic tumour and between epidermoid tumour and arachnoid cyst. On the other hand, the results obtained with diffusion MR in the characterisation of type and extension of glioma do not yet allow decision making in the individual patient. Diffusion is one of the most relevant MR techniques to have contributed to a better understanding of the pathophysiological mechanisms of multiple sclerosis (MS). In fact, it improves the specificity of MR in characterising the different pathological substrata underlying the rather uniform lesion appearance on the conventional images and enables detection of damage in the normal-appearing white and grey matter. In MS patients the ADC or D values in the normal-appearing white matter are increased as compared to control values, albeit to a lesser degree than in the lesions demonstrated by T2-weighted images. In addition, the D of the normal appearing grey matter is increased in MS patients and this change correlates with the cognitive deficit of these patients. Histogram analysis in MS patients shows that the peak of the brain D is decreased and right-shifted, reflecting an increase of its value, and the two features correlate with the patient's clinical disability. Ageing is associated to a mild but significant increase of the brain ADC or D which is predominantly due to changes in the white matter. Region of interest and histogram studies have demonstrated that D or ADC are increased in
Intracranial meningiomas, the VEGF-A pathway, and peritumoral brain oedema.
Meningiomas are the second-most common intracranial tumours in adults. They are derived from the arachnoid cells, and although approximately 90% of meningiomas are benign, more than half of all meningiomas develop peritumoral brain oedema (PTBE), which increases morbidity. The PTBE can be treated with steroid therapy, but this treatment is not specific, is not always effective, and involves long-term side-effects. Meningiomas are treated with radiation therapy, stereotactic radio-surgery or surgical resection. At the moment surgical resection is the only definite treatment, and the removal of the tumour also removes the PTBE. Based on the localization of the meningioma, surgery can be complicated. Although PTBE around meningiomas is frequent, the mechanisms behind its development are not clearly understood. It is believed that due to tumour growth and local tissue hypoxia, angiogenesis is increased and leads to the formation of PTBE. The angiogenic protein vascular endothelial growth factor A (VEGF-A) is believed to be involved in the formation of PTBE around meningiomas, as several studies have found that it is increased in meningiomas with PTBE. VEGF-A is also known as vascular permeability factor due to its ability to increase the permeability of capillaries. Paper I examines the VEGF-A protein and mRNA levels in 101 intracranial meningiomas. The PTBE is quantified on MRI, and capillary length and tumour water content are measured and compared to control brain tissue. Possible co-factors to PTBE like meningioma localization and subtypes are also examined. Forty-three of the patients have primary, solitary, supratentorial meningiomas with PTBE. The correlation between PTBE or edema index with the VEGF-A protein and mRNA, capillary length, and tumour water content is investigated in these patients. A novel method is used for mRNA quantification. It involves direct amplification of the mRNA with probes and branched DNA in order to produce a chemiluminescence signal