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Qureshi HM, Mekbib KY, Allington G, Elsamadicy AA, Duy PQ, Kundishora AJ, Jin SC, Kahle KT. Familial and syndromic forms of arachnoid cyst implicate genetic factors in disease pathogenesis. Cereb Cortex 2023; 33:3012-3025. [PMID: 35851401 PMCID: PMC10388392 DOI: 10.1093/cercor/bhac257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 06/01/2022] [Accepted: 06/04/2022] [Indexed: 11/13/2022] Open
Abstract
Arachnoid cysts (ACs) are the most common space-occupying lesions in the human brain and present significant challenges for clinical management. While most cases of ACs are sporadic, nearly 40 familial forms have been reported. Moreover, ACs are seen with increased frequency in multiple Mendelian syndromes, including Chudley-McCullough syndrome, acrocallosal syndrome, and autosomal recessive primary ciliary dyskinesia. These findings suggest that genetic factors contribute to AC pathogenesis. However, traditional linkage and segregation approaches have been limited in their ability to identify causative genes for ACs because the disease is genetically heterogeneous and often presents asymptomatically and sporadically. Here, we comprehensively review theories of AC pathogenesis, the genetic evidence for AC formation, and discuss a different approach to AC genomics that could help elucidate this perplexing lesion and shed light on the associated neurodevelopmental phenotypes seen in a significant subset of these patients.
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Affiliation(s)
- Hanya M Qureshi
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT 06510, United States
| | - Kedous Y Mekbib
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT 06510, United States
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, United States
| | - Garrett Allington
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, United States
- Department of Pathology, Yale University School of Medicine, New Haven, CT 06510, United States
| | - Aladine A Elsamadicy
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT 06510, United States
| | - Phan Q Duy
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT 06510, United States
| | - Adam J Kundishora
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT 06510, United States
| | - Sheng Chih Jin
- Department of Genetics, Washington University School of Medicine, St. Louis, MO 63110, United States
| | - Kristopher T Kahle
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT 06510, United States
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, United States
- Division of Genetics and Genomics, Boston Children’s Hospital, Boston, MA 02115, United States
- Department of Pediatrics, Harvard Medical School, Boston, MA 02115, United States
- Department of Neurology, Harvard Medical School, Boston, MA 02115, United States
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, United States
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Beltagy MAE, Enayet AER. Surgical indications in pediatric arachnoid cysts. Childs Nerv Syst 2023; 39:87-92. [PMID: 36284010 DOI: 10.1007/s00381-022-05709-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 10/13/2022] [Indexed: 11/03/2022]
Abstract
INTRODUCTION Arachnoid cysts are developmental lesions consisting of CSF collections within the subarachnoid space. There are many theories and hypotheses about their pathogenesis and histopathology and this may also explain the diversities seen in clinical behaviors of these cysts, their natural history and consequently their management where there is a great controversy about selecting patients for surgical intervention. The most common location in pediatrics is the Sylvian or middle cranial fossa and this made it gain more concern and greater debate about its management where its diagnosis is often accidently or associated with nonspecific symptoms. AIM Our aim in this article was to review the main surgical indications for pediatric arachnoid cysts in the literature. CONCLUSION We concluded that the decision for surgical intervention for pediatric arachnoid cysts is not a simple one and highly debatable and should be taken cautiously especially with sylvian arachnoid cysts that may reach a large size without symptoms. However, there is a consensus that the occurrence of symptoms definitely correlated to the presence of these cysts or their rupture with consequent subdural hematoma or hygroma are indications for surgical intervention. Large cysts in locations compressing CSF pathways causing hydrocephalus are also candidates for surgical fenestration. The surgical gain from prophylactic surgery is questionable particularly when asymptomatic.
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Affiliation(s)
- Mohamed A El Beltagy
- Children's Cancer Hospital Egypt (CCHE, 57357), Cairo, Egypt. .,Neurosurgery Department, Kasr Al-Ainy School of Medicine, Cairo University, Cairo, Egypt.
| | - Abd El Rhman Enayet
- Children's Cancer Hospital Egypt (CCHE, 57357), Cairo, Egypt.,Neurosurgery Department, Kasr Al-Ainy School of Medicine, Cairo University, Cairo, Egypt
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Gale JR, Nowicki KW, Wolfe RM, Sefcik RK, Abel TJ. Infection of arachnoid cyst associated with vasospasm and stroke in a pediatric patient: case report. J Neurosurg Pediatr 2020; 26:594-598. [PMID: 32858508 DOI: 10.3171/2020.5.peds20419] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 05/22/2020] [Indexed: 11/06/2022]
Abstract
Arachnoid cysts are relatively common and benign intraarachnoid membrane outpouchings containing CSF-like fluid. The majority of arachnoid cysts remain stable and asymptomatic and do not require intervention in the pediatric population. Here, the authors present the first reported case of an infected arachnoid cyst in a pediatric patient resulting in severe vasospasm of the left terminal internal carotid artery, left A1 segment, and left M1 branches with a left middle cerebral artery infarct. Their experience suggests that close monitoring is warranted for this condition and that the pediatric population may be at higher risk for vasospasm.
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Affiliation(s)
- Jenna R. Gale
- Department of Neurological Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Kamil W. Nowicki
- Department of Neurological Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Rachel M. Wolfe
- Department of Neurological Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Roberta K. Sefcik
- Department of Neurological Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Taylor J. Abel
- Department of Neurological Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
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Abstract
INTRODUCTION Arachnoid cysts are commonly considered congenital lesions, but this has not been proven. With the development of neuroimaging and DNA testing technology, more cases of familial arachnoid cysts have been reported. Herein, we review such cases. MATERIALS AND METHODS The PubMed, Embase, and Web of Science databases were searched for case reports of arachnoid cysts published through April 2018. Case reports were included only if two or more related patients were diagnosed with an arachnoid cyst by neuroimaging or intraoperatively. For each report, the following data were extracted: first author name, date of publication, number of families, number of patients, location of the arachnoid cysts, patient age, patient sex, and genetic mutations and associated disease. RESULTS Our searches identified 33 case reports involving 35 families and 115 patients. The locations of arachnoid cysts were similar in 25 of the 35 families. Spinal extradural arachnoid cysts were reported most often, followed by arachnoid cysts in the middle fossa and posterior fossa. A left-sided predominance was noticed for arachnoid cysts of the middle fossa. Mutation of the FOXC2 gene was reported most often, and arachnoid cysts may be associated with mutations on chromosome 16. CONCLUSIONS Although the origin of arachnoid cysts is believed to have a genetic component by some researchers, the genes associated with arachnoid cysts remain unknown. Unfortunately, the evidence remains insufficient.
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Furey CG, Timberlake AT, Nelson-Williams C, Duran D, Li P, Jackson EM, Kahle KT. Xp22.2 Chromosomal Duplication in Familial Intracranial Arachnoid Cyst. JAMA Neurol 2019; 74:1503-1504. [PMID: 29052703 DOI: 10.1001/jamaneurol.2017.3399] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Charuta G Furey
- Department of Neurosurgery, Yale University School of Medicine, New Haven, Connecticut.,Department of Genetics, Yale University School of Medicine, New Haven, Connecticut
| | - Andrew T Timberlake
- Department of Genetics, Yale University School of Medicine, New Haven, Connecticut.,Section of Plastic and Reconstructive Surgery, Yale University School of Medicine, New Haven, Connecticut
| | | | - Daniel Duran
- Department of Neurosurgery, Yale University School of Medicine, New Haven, Connecticut.,Department of Genetics, Yale University School of Medicine, New Haven, Connecticut
| | - Peining Li
- Department of Genetics, Yale University School of Medicine, New Haven, Connecticut
| | - Eric M Jackson
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Kristopher T Kahle
- Department of Neurosurgery, Yale University School of Medicine, New Haven, Connecticut.,Department of Genetics, Yale University School of Medicine, New Haven, Connecticut
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McNamara HC, Kane SC, Craig JM, Short RV, Umstad MP. A review of the mechanisms and evidence for typical and atypical twinning. Am J Obstet Gynecol 2016; 214:172-191. [PMID: 26548710 DOI: 10.1016/j.ajog.2015.10.930] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 10/28/2015] [Accepted: 10/29/2015] [Indexed: 12/11/2022]
Abstract
The mechanisms responsible for twinning and disorders of twin gestations have been the subject of considerable interest by physicians and scientists, and cases of atypical twinning have called for a reexamination of the fundamental theories invoked to explain twin gestations. This article presents a review of the literature focusing on twinning and atypical twinning with an emphasis on the phenomena of chimeric twins, phenotypically discordant monozygotic twins, mirror-image twins, polar body twins, complete hydatidiform mole with a coexistent twin, vanishing twins, fetus papyraceus, fetus in fetu, superfetation, and superfecundation. The traditional models attributing monozygotic twinning to a fission event, and more recent models describing monozygotic twinning as a fusion event, are critically reviewed. Ethical restrictions on scientific experimentation with human embryos and the rarity of cases of atypical twinning have limited opportunities to elucidate the exact mechanisms by which these phenomena occur. Refinements in the modeling of early embryonic development in twin pregnancies may have significant clinical implications. The article includes a series of figures to illustrate the phenomena described.
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Affiliation(s)
- Helen C McNamara
- Department of Maternal-Fetal Medicine, Royal Womens Hospital, Melbourne, Victoria, Australia
| | - Stefan C Kane
- Department of Maternal-Fetal Medicine, Royal Womens Hospital, Melbourne, Victoria, Australia; Department of Obstetrics and Gynaecology, University of Melbourne, Melbourne, Victoria, Australia
| | - Jeffrey M Craig
- Murdoch Childrens Research Institute, Royal Children's Hospital, Melbourne, Victoria, Australia
| | - Roger V Short
- Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne, Victoria, Australia
| | - Mark P Umstad
- Department of Maternal-Fetal Medicine, Royal Womens Hospital, Melbourne, Victoria, Australia; Department of Obstetrics and Gynaecology, University of Melbourne, Melbourne, Victoria, Australia.
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Lubala TK, Mbuyi-Musanzayi S, Lubala N, Luboya ON, Kalenga PM, Devriendt K, Lukusa-Tshilobo P. Mirror-image gastroschisis in monochorionic female twins. Eur J Med Genet 2015; 58:266-9. [DOI: 10.1016/j.ejmg.2015.03.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Accepted: 03/08/2015] [Indexed: 11/29/2022]
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Rabiei K, Tisell M, Wikkelsø C, Johansson BR. Diverse arachnoid cyst morphology indicates different pathophysiological origins. Fluids Barriers CNS 2014; 11:5. [PMID: 24581284 PMCID: PMC4078003 DOI: 10.1186/2045-8118-11-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2013] [Accepted: 02/03/2014] [Indexed: 01/30/2023] Open
Abstract
BACKGROUND There are few, limited, and to some extent contradictory, reports on the cellular and subcellular morphology of arachnoid cysts. In the literature cyst membranes are described as similar to, or as vastly different from, normal arachnoid membranes. METHODS This paper reports electron microscopic analyses of symptomatic cysts from 24 patients (12 males and 12 females; age 10-79), that underwent fenestration surgery. Fourteen cysts were located in the middle cranial fossa (temporal), one in the interpeduncular cistern, five in the posterior fossa, and four were overlying the frontal cortex. RESULTS Microscopic findings confirmed the diverse nature of this clinical condition. Twelve cyst walls resembled normal arachnoid, four had a conspicuous core of dense fibrous tissue with a simple epithelial lining, and the remaining aberrant cysts exhibited non-arachnoid luminal epithelia with plentiful microvilli and/or cilia, and also nervous tissue components in the wall. The possible identity and origin of various cyst types are discussed. We hypothesize that cysts are formed mostly at an early stage of embryonic development, as a teratological event. CONCLUSIONS Cysts with various epithelial linings and extracellular components most likely have different barrier properties and fluid turnover characteristics. Further studies are needed to elucidate relations between cyst morphology, fluid composition, pathogenesis, and clinical behaviour including growth rate and relapse tendency.
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Affiliation(s)
- Katrin Rabiei
- Institute of Neuroscience and Physiology, c/o Neurosurgical Clinic, Sahlgrenska University Hospital, Gothenburg SE-413 45, Sweden.
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Ma K. Embryonic left-right separation mechanism allows confinement of mutation-induced phenotypes to one lateral body half of bilaterians. Am J Med Genet A 2013; 161A:3095-114. [PMID: 24254848 DOI: 10.1002/ajmg.a.36188] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Accepted: 07/16/2013] [Indexed: 11/08/2022]
Abstract
A fundamental question in developmental biology is how a chimeric animal such as a bilateral gynandromorphic animal can have different phenotypes confined to different lateral body halves, and how mutation-induced phenotypes, such as genetic diseases, can be confined to one lateral body half in patients. Here, I propose that embryos of many, if not all, bilaterian animals are divided into left and right halves at a very early stage (which may vary among different types of animals), after which the descendants of the left-sided and right-sided cells will almost exclusively remain on their original sides, respectively, throughout the remaining development. This embryonic left-right separation mechanism allows (1) mutations and the mutation-induced phenotypes to be strictly confined to one lateral body half in animals and humans; (2) mothers with bilateral hereditary primary breast cancer to transmit their disease to their offspring at twofold of the rate compared to mothers with unilateral hereditary breast cancer; and (3) a mosaic embryo carrying genetic or epigenetic mutations to develop into either an individual with the mutation-induced phenotype confined unilaterally, or a pair of twins displaying complete, partial, or mirror-image discordance for the phenotype. Further, this left-right separation mechanism predicts that the two lateral halves of a patient carrying a unilateral genetic disease can each serve as a case and an internal control, respectively, for genetic and epigenetic comparative studies to identify the disease causations.
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Al-Holou WN, Terman S, Kilburg C, Garton HJL, Muraszko KM, Maher CO. Prevalence and natural history of arachnoid cysts in adults. J Neurosurg 2013; 118:222-31. [DOI: 10.3171/2012.10.jns12548] [Citation(s) in RCA: 169] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Object
Arachnoid cysts are a frequent finding on intracranial imaging. The prevalence and natural history of these cysts in adults are not well defined.
Methods
We retrospectively reviewed the electronic medical records of a consecutive series of adults who underwent brain MRI over a 12-year interval to identify those with arachnoid cysts. The MRI studies were reviewed to confirm the diagnosis. For those patients with arachnoid cysts, we evaluated presenting symptoms, cyst size, and cyst location. Patients with more than 6 months' clinical and imaging follow-up were included in a natural history analysis.
Results
A total of 48,417 patients underwent brain MRI over the study period. Arachnoid cysts were identified in 661 patients (1.4%). Men had a higher prevalence than women (p < 0.0001). Multiple arachnoid cysts occurred in 30 patients. The most common locations were middle fossa (34%), retrocerebellar (33%), and convexity (14%). Middle fossa cysts were predominantly left-sided (70%, p < 0.001). Thirty-five patients were considered symptomatic and 24 underwent surgical treatment. Sellar and suprasellar cysts were more likely to be considered symptomatic (p < 0.0001). Middle fossa cysts were less likely to be considered symptomatic (p = 0.01. The criteria for natural history analysis were met in 203 patients with a total of 213 cysts. After a mean follow-up of 3.8 ± 2.8 years (for this subgroup), 5 cysts (2.3%) increased in size and 2 cysts decreased in size (0.9%). Only 2 patients developed new or worsening symptoms over the follow-up period.
Conclusions
Arachnoid cysts are a common incidental finding on intracranial imaging in all age groups. Although arachnoid cysts are symptomatic in a small number of patients, they are associated with a benign natural history for those presenting without symptoms.
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Zhou JY, Pu JL, Chen S, Hong Y, Ling CH, Zhang JM. Mirror-image arachnoid cysts in a pair of monozygotic twins: a case report and review of the literature. Int J Med Sci 2011; 8:402-5. [PMID: 21750644 PMCID: PMC3133845 DOI: 10.7150/ijms.8.402] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2011] [Accepted: 05/23/2011] [Indexed: 11/12/2022] Open
Abstract
Mirror-imaging of arachnoid cysts (ACs) in monozygotic twins (MZ) is extremely rare. We describe a pair of MZ who developed mirror-imaging of ACs in the temporal fossas, and we also review the literature. Brain computer tomography (CT) and Magnetic Resonance Imaging (MRI) of the MZ revealed mirror-imaging of vast lesions of cerebrospinal fluid intensity in their temporal fossas. This is the second ever report of such a case according to the available literature. Unlike the prior case, our patients were 14 months, which is a much younger age than the patients of the previous report. Consequently, our case is better in supporting a genetic origin in the pathogenesis of AC. The findings in our case indicate that early neuroimaging is mandatory in the counterpart of the symptomatic patient with AC, irrespective of the absence of symptoms.
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Affiliation(s)
- Jing-Yi Zhou
- 1. Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Jia-Li Pu
- 2. Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Sheng Chen
- 1. Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Yuan Hong
- 1. Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Chen-Han Ling
- 1. Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Jian-Min Zhang
- 1. Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
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Helland CA, Lund-Johansen M, Wester K. Location, sidedness, and sex distribution of intracranial arachnoid cysts in a population-based sample. J Neurosurg 2010; 113:934-9. [DOI: 10.3171/2009.11.jns081663] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Object
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.
Methods
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.
Results
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.
Conclusions
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.
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Berle M, Wester KG, Ulvik RJ, Kroksveen AC, Haaland OA, Amiry-Moghaddam M, Berven FS, Helland CA. Arachnoid cysts do not contain cerebrospinal fluid: A comparative chemical analysis of arachnoid cyst fluid and cerebrospinal fluid in adults. Cerebrospinal Fluid Res 2010; 7:8. [PMID: 20537169 PMCID: PMC2898803 DOI: 10.1186/1743-8454-7-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2010] [Accepted: 06/10/2010] [Indexed: 11/10/2022] Open
Abstract
Background Arachnoid cyst (AC) fluid has not previously been compared with cerebrospinal fluid (CSF) from the same patient. ACs are commonly referred to as containing "CSF-like fluid". The objective of this study was to characterize AC fluid by clinical chemistry and to compare AC fluid to CSF drawn from the same patient. Such comparative analysis can shed further light on the mechanisms for filling and sustaining of ACs. Methods Cyst fluid from 15 adult patients with unilateral temporal AC (9 female, 6 male, age 22-77y) was compared with CSF from the same patients by clinical chemical analysis. Results AC fluid and CSF had the same osmolarity. There were no significant differences in the concentrations of sodium, potassium, chloride, calcium, magnesium or glucose. We found significant elevated concentration of phosphate in AC fluid (0.39 versus 0.35 mmol/L in CSF; p = 0.02), and significantly reduced concentrations of total protein (0.30 versus 0.41 g/L; p = 0.004), of ferritin (7.8 versus 25.5 ug/L; p = 0.001) and of lactate dehydrogenase (17.9 versus 35.6 U/L; p = 0.002) in AC fluid relative to CSF. Conclusions AC fluid is not identical to CSF. The differential composition of AC fluid relative to CSF supports secretion or active transport as the mechanism underlying cyst filling. Oncotic pressure gradients or slit-valves as mechanisms for generating fluid in temporal ACs are not supported by these results.
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Affiliation(s)
- Magnus Berle
- Institute of Medicine, University of Bergen, 5021 Bergen, Norway.
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