Spontaneous meningioma in a pig-tailed macaque (Macaca nemestrina)

Abstract. We present a case of spontaneous meningioma in a female pig-tailed macaque (Macaca nemestrina) more than 24 years old. Clinically, the monkey displayed slow, weak, and insecure movements and poor vision. A tumorous mass was present at the floor of the cranial vault extending from the optic chiasm towards the foramen magnum. It compressed adjacent parts of the brain, infiltrated the sphenoidal and occipital bone, and showed transcranial expansion into the pharyngeal area. Histologically, the tumor was consistent with a meningioma displaying mostly meningothelial and some microcystic components. Since only six cases of meningiomas in nonhuman primates have been reported so far and only two of these meningiomas have been described in detail, the findings of each case should be reported to expand the knowledge base of this type of tumor. In addition, this is the first description of a meningioma in pig-tailed macaques.

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Surgical Management of Chiari Malformations: Preliminary Results of Surgery According to the Mechanisms of Ptosis of the Brain Stem and Cerebellum

Journal of Neurological Surgery Part B Skull Base ◽

10.1055/s-0039-1697977 ◽

2019 ◽

Cited By ~ 1

Author(s):

Misao Nishikawa ◽

Paolo A. Bolognese ◽

Roger W. Kula ◽

Hiromichi Ikuno ◽

Toshihiro Takami ◽

...

Keyword(s):

Brain Stem ◽

Chiari Malformation ◽

Foramen Magnum ◽

Neurological Symptoms ◽

Bone Size ◽

Occipital Bone ◽

High Rate ◽

Type C ◽

The Brain ◽

Rate Of Improvement

Abstract Introduction We classified Chiari malformation type I (CM-I) according to the mechanism of ptosis of the brain stem and cerebellum, based on a morphometric study of the posterior cranial fossa (PCF) and craniovertebral junction (CVJ). Surgery was performed to manage the mechanism of the hindbrain ptosis. Materials and Methods We calculated the volume of the PCF (VPCF) and the area surrounding the foramen magnum (VSFM) and measured the axial length of the enchondral parts of the occipital bone (occipital bone size) and the hindbrain. According to these measures, we classified CM-I into type A (normal VPCF, normal VSFM, and normal occipital bone size), type B (normal VPCF, small VSFM, and small occipital bone size), and type C (small VPCF, small VSFM, and small occipital bone size). Foramen magnum decompression (FMD) (280 cases) was performed on CM-I types A and B. Expansive suboccipital cranioplasty (ESCP) was performed on CM-I type C. Posterior craniocervical fixation (CCF) was performed in cases with CVJ instability. Lysis of the adhesion and/or sectioning of the filum terminale were performed on cases with tethered cord syndrome. Results Both ESCP and FMD had a high rate of improvement of neurological symptoms (87%) and recovery rate. There was only small number of complications. CCF had a high rate of improvement of neurological symptoms (88%) and joint stabilization. Conclusion In the management of Chiari malformation, appropriate surgical methods that address ptosis of the hindbrain should be chosen. Each surgical approach resulted in a good improvement of neurological symptoms.

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Primary Cranial Vault Lymphoma Extending between Subcutaneous Tissue and Brain Parenchyma without Skull Destruction after Mild Head Trauma: A Case Report and Literature Review

Case Reports in Oncology ◽

10.1159/000516272 ◽

2021 ◽

pp. 1118-1123

Author(s):

Kengo Setta ◽

Takaaki Beppu ◽

Yuichi Sato ◽

Hiroaki Saura ◽

Junichi Nomura ◽

...

Keyword(s):

Tumor Cells ◽

Head Trauma ◽

Dura Mater ◽

Subcutaneous Tissue ◽

Bone Destruction ◽

B Cell Lymphoma ◽

Brain Parenchyma ◽

Skin Tumor ◽

Cranial Vault ◽

The Brain

Malignant lymphoma of the head rarely arises outside of the brain parenchyma as primary cranial vault lymphoma (PCVL). A case of PCVL that invaded from subcutaneous tissue into the brain, passing through the skull, and occurred after mild head trauma is reported along with a review of the literature. The patient was a 75-year-old man with decreased activity. One month before his visit to our hospital, he bruised the left frontal area of his head. Magnetic resonance imaging showed homogeneously enhanced tumors with contrast media in the subcutaneous tissue corresponding to the head impact area and the cerebral parenchyma, but no obvious abnormal findings in the skull. A biopsy with craniotomy was performed under general anesthesia. The pathological diagnosis was diffuse large B-cell lymphoma. On histological examination, tumor cells grew aggressively under the skin. Tumor cells invaded along the emissary vein into the external table without remarkable bone destruction and extended across the skull through the Haversian canals in the diploe. Tumor cells were found only at the perivascular areas in the dura mater and extended into the brain parenchyma. Considering the history of head trauma and the neuroimaging and histological findings, the PCVL in the present case arose primarily under the skin, passed though the skull and dura mater, and invaded along vessels and reached the brain.

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MicroPET/CT assessment of neurochemical effects in the brain after long-term methylphenidate treatment in nonhuman primates

Neurotoxicology and Teratology ◽

10.1016/j.ntt.2021.107017 ◽

2021 ◽

pp. 107017

Author(s):

X. Zhang ◽

J. Talpos ◽

M.S. Berridge ◽

S.M. Apana ◽

W. Slikker ◽

...

Keyword(s):

Nonhuman Primates ◽

The Brain

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Influence of Foramen Magnum Boundary Condition on Intracranial Dynamic Response Under Forehead Impact Using Human Body Finite Element Model

International Journal of Computational Methods ◽

10.1142/s0219876219500294 ◽

2019 ◽

Vol 17 (07) ◽

pp. 1950029 ◽

Cited By ~ 1

Author(s):

Lihai Ren ◽

Dangdang Wang ◽

Chengyue Jiang ◽

Yuanzhi Hu

Keyword(s):

Boundary Condition ◽

Finite Element ◽

Brain Stem ◽

Axonal Injury ◽

Human Head ◽

Foramen Magnum ◽

Dynamic Responses ◽

Human Model ◽

Modeling Methods ◽

The Brain

The biofidelity is an essential requirement of the application of human head finite element (FE) models to investigate head injuries under mechanical loadings. However, the influence of the foramen magnum boundary condition (FMBC) on intracranial dynamic responses under head impacts has yet to be fully identified until now. This study aimed to investigate the effect of different modeling methods of the FMBC on intracranial dynamic responses induced by forehead impact, especially the axonal injury associated dynamic responses. The total human model for safety (THUMS) was applied in this study. Two FE models with different FMBC modeling methods were developed from the THUMS model. Then, three forehead impact FE models were established respectively, including the original THUMS model. Further FE simulations were conducted to investigate the influence of FMBC modeling methods on intracranial dynamic responses. Though, difference between the intracranial dynamic responses (relative skull-brain motion and strain responses) at areas far from the foramen magnum were slightly, the corresponding difference at the brain stem area were distinctly. Meanwhile, the predicted axonal injury risk of the brain stem white matter was varying among each other. Different modeling methods of FMBC could result in different intracranial dynamic responses of the brain stem, and affect the axonal injury prediction. Therefore, the modeling of the FMBC should be further evaluated for the study of brain stem injury using human head FE models.

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Anatomical Study of Intrahemispheric Association Fibers in the Brains of Capuchin Monkeys (Sapajussp.)

BioMed Research International ◽

10.1155/2015/648128 ◽

2015 ◽

Vol 2015 ◽

pp. 1-6 ◽

Cited By ~ 5

Author(s):

Kellen Christina Malheiros Borges ◽

Hisao Nishijo ◽

Tales Alexandre Aversi-Ferreira ◽

Jussara Rocha Ferreira ◽

Leonardo Ferreira Caixeta

Keyword(s):

Nonhuman Primates ◽

Evolutionary Process ◽

Anatomical Study ◽

Lateral View ◽

Superior Longitudinal Fasciculus ◽

Cognitive Behaviors ◽

Behavioral Studies ◽

Inferior Longitudinal Fasciculus ◽

Association Fibers ◽

The Brain

Previous studies suggest that the complexity of fiber connections in the brain plays a key role in the evolutionary process of the primate brain and behaviors. The patterns of brain fiber systems have been studied in detail in many nonhuman primates, but not inSapajussp. Behavioral studies indicated thatSapajussp. (bearded capuchins) show highly cognitive behaviors such as tool use comparable to those in other nonhuman primates. To compare the brain fiber systems in capuchins with those in other nonhuman primates and humans, the intrahemispheric fibers systems in 24 cerebral hemispheres ofSapajuswere dissected by a freezing-thawing procedure. Dissection of the hemispheres in lateral view indicated short arcuate fibers, uncinate fasciculus, and inferior longitudinal fasciculus, while that in a medial view indicated short arcuate fibers, the cingulum united with the superior longitudinal fasciculus, and inferior longitudinal fasciculus. The results showed that the fiber systems inSapajusare comparable to those in rhesus and humans, except for a lack of independent superior longitudinal fasciculus and cingulum inSapajus.

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Foramen Magnum Stenosis in Achondroplasia

Austin Journal of Radiology ◽

10.26420/austinjradiol.2021.1136 ◽

2021 ◽

Vol 8 (4) ◽

Author(s):

Choayb S ◽

◽

Adil H ◽

El Haddad S ◽

◽

...

Keyword(s):

Sudden Death ◽

Skull Base ◽

Short Stature ◽

Skeletal Dysplasia ◽

Endochondral Ossification ◽

Foramen Magnum ◽

Severe Complication ◽

Occipital Bone ◽

Severe Morbidity ◽

Cervicomedullary Junction

Achondroplasia is the most common hereditary skeletal dysplasia and is characterized by disproportionately short stature with rhizomelic short extremities [1]. The skull features include a narrowed foramen magnum, short skull base, and clivus [2]. Foramen magnum stenosis is a characteristic funding, secondary to an abnormal placement and premature fusion of the posterior synchondroses [1]. The second factor responsible for stenosis is a defect in endochondral ossification in the basiocciput that may result in an extension of the squamous occipital bone [2]. It can cause hydrocephalus and prominent emissary and meningeal veins (Figure 1). Figure 1: Sagittal T1WI revealing a narrowed stenosis of the foramen magnum and compression of the cervicomedullary junction. The most severe complication is the compression of the cervicomedullary junction, associated with severe morbidity and sudden death in younger children [1].

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VARIANTS OF MASTOID AND OCCIPITAL EMISSARY FORAMENS AND THEIR CLINICAL CORRELATION

Journal of IMAB - Annual Proceeding (Scientific Papers) ◽

10.5272/jimab.2021274.4004 ◽

2021 ◽

Vol 27 (4) ◽

pp. 4004-4009

Author(s):

Ivan Maslarski ◽

◽

Lyudmila Belenska-Todorova ◽

Keyword(s):

Varicose Veins ◽

Foramen Magnum ◽

Clinical Correlation ◽

Tissue Separation ◽

Emissary Veins ◽

Important Study ◽

Long Time ◽

The Brain ◽

Standard Techniques ◽

Dural Venous Sinuses

Purpose: Emissary foramens in the skull and emissary veins (EV), respectively, have been known for a long time, but their importance is often disregarded. In the present study, we introduce variants of occipital emissary foramens (OEF) unilaterally located on the left, close to оccipital condylе in a formation of three apertures that open together in a sinus near clivus. Material/Methods: Corpses of 30 dеad people were dissected in the Department of Anatomy, and standard techniques for soft tissue separation or maceration of the skull were used. After the removal of the calvaria, fixed bones of the skull were disarticulated. Foramens were cleaned using a double-ended probe, and depth and diameter measurements were performed using an atomical caliper. Results: We found variants of mastoid emissary foramens (MEF) situated into two groups, each of a couple of foramens. Their clinical significance is discussed, compared with existing experience and analysis of their phylogeny and embryogenesis. Conclusion: We introduce OEF and MEF to be important markers for detection of dural venous sinuses (DVS). The latter, together with EV, provide an important mechanism for decreasing intracranial pressure. This happens due to the absence of a valve apparatus in the veins of the brain, and the lack, or small amount, of muscle tissue. There is a possibility of existing varicose veins, such as those caused by arterio-venous fistulas and the pathology associated with it. We suggest the application of EV in imaging as an important study before surgery by lateral and transcondylar approach to the anterior foramen magnum.

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Ocular, Neurologic and Systemic Findings of the Cases with Optic Nerve Hypoplasia

The Open Ophthalmology Journal ◽

10.2174/1874364101610010005 ◽

2016 ◽

Vol 10 (1) ◽

pp. 5-11 ◽

Cited By ~ 3

Author(s):

Eyyup Karahan ◽

Ayse Tulin Berk

Keyword(s):

Optic Nerve ◽

Chart Review ◽

Retrospective Chart Review ◽

Optic Nerve Hypoplasia ◽

Refractive Errors ◽

Poor Vision ◽

The Relationship ◽

The Brain ◽

Ocular Signs ◽

Neurologic Findings

Aim: To describe the associated ocular, neurologic, and systemic findings in a population of children with optic nerve hypoplasia (ONH) and to evaluate the relationship between ocular signs and neurologic findings. Method: A retrospective chart review of 53 patients with the diagnosis of ONH seen between December 1998 and September 2012 was performed. All neurodevelopmental anomalies, neuroradiologic findings, endocrinologic and systemic findings were recorded. Poor vision was defined as the visual acuity poorer than logMAR 1.0 or inadequate central steady maintained fixation. Results: Thirty (56.6%) of the 53 children with ONH were boys. Mean age at presentation was 56.2±46.8 months (range; 3 months to 18 years). Poor vision defined for the purpose of this study was found in 47.2% of 53 patients. Thirty-three (62.3%) children had nystagmus. Thirty-four (64.2%) children had strabismus. Thirteen (38.2%) of those with strabismus had esotropia, 20 (58.8%) had exotropia. The total number of the children with neurodevelopmental deficit was 22 (41.5%) in our study. Conclusion: The vision of young children with ONH should be monitored at least annually, and any refractive errors should be treated. Neuroimaging of the brain and endocrinologic evaluation is necessary in all cases with ONH.

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Giant high occipital encephalocele

Romanian Neurosurgery ◽

10.1515/romneu-2016-0020 ◽

2016 ◽

Vol 30 (1) ◽

pp. 122-126

Author(s):

Amit Agrawal ◽

Reddy V. Umamaheshwara ◽

Kishor V. Hegde ◽

P. Suneetha ◽

Divya Siddharth Kolikipudi

Keyword(s):

Ct Images ◽

Foramen Magnum ◽

Defect Size ◽

Occipital Bone ◽

Developmental Anomalies ◽

Occipital Encephalocele ◽

Adjacent Structures ◽

Vascular Structures ◽

Osseous Defect ◽

Ct And Mri

Abstract Encephaloceles are rare embryological mesenchymal developmental anomalies resulting from inappropriate ossification in skull through with herniation of intracranial contents of the sac. Encephaloceles are classified based on location of the osseous defect and contents of sac. Convexity encephalocele with osseous defect in occipital bone is called occipital encephalocele. Giant occipital encephaloceles can be sometimes larger than the size of baby skull itself and they pose a great surgical challenge. Occipital encephaloceles (OE) are further classified as high OE when defect is only in occipital bone above the foramen magnum, low OE when involving occipital bone and foramen magnum and occipito-cervical when there involvement of occipital bone, foramen magnum and posterior upper neural arches. Chiari III malformation can be associated with high or low occipital encephaloceles. Pre-operatively, it is essential to know the size of the sac, contents of the sac, relation to the adjacent structures, presence or absence of venous sinuses/vascular structures and osseous defect size. Sometimes it becomes imperative to perform both CT and MRI for the necessary information. Volume rendered CT images can depict the relation of osseous defect to foramen magnum and provide information about upper neural arches which is necessary in classifying these lesions.

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Morphologic and Osteometric Analysis of the Skull of Markhoz Goat (Iranian Angora)

Veterinary Medicine International ◽

10.1155/2014/972682 ◽

2014 ◽

Vol 2014 ◽

pp. 1-5 ◽

Cited By ~ 4

Author(s):

Nader Goodarzi ◽

Toraj Shah Hoseini

Keyword(s):

Foramen Magnum ◽

Parietal Bone ◽

Frontal Bone ◽

Occipital Bone ◽

Cheek Tooth ◽

Frontal Surface ◽

Infraorbital Foramen ◽

Skull Length ◽

Cranial Index

This study provides some comprehensive osteometric and morphologic descriptions of the skull region of the Markhoz goat. Totally, 17 osteometric parameters of eight skulls of Markhoz goat were measured and expressed as mean ± SD. A skull length of18.67±0.66, a cranial length of11.1±0.38, a facial length of10.23±0.76, a skull index of47.77±1.96, a cranial index of54.04±2.29, a facial index of100.77±6.85and a foramen magnum index of89.32±14.1were recorded. Morphologically frontal bone did not constitute the caudal extent of frontal surface; rather it was formed by the parietal bone. There were two supraorbital foramina in both sides. The prominent facial tuberosity lies dorsally to the 3rd cheek tooth. The infraorbital foramen was single on either side which was located directly dorsally to the junction of the first and second upper premolar. The orbits were round and complete and located on a frontolateral oblique plane. The basilar part of the occipital bone was surrounded by two pairs of muscular tubercles with similar size. The temporal line was continuous of the temporal crest and ran over the parietal bone. In conclusion, the morphologic and osteometric data of Markhoz goat are comparable to other ruminants.

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