Cytopathologic features of orbital intraosseous chordoid meningioma: Report of a case and distinction from other myxoid/mucoid tumors

Chordoid meningioma (CM) is characterized by a striking histologic resemblance to chordoma and propensity for aggressive behavior or recurrence (WHO grade II designation). Orbital intraosseous CM is extremely uncommon and only one case report has been documented. A case is presented here in which squash smears of a left orbital tumor in a 53‐year‐old male revealed small clusters or cord‐like structures of bland tumor cells embedded in a myxoid or mucinous background. Whorl‐like structures were also identified. The tumor cells possessed uniformly round nuclei with a smooth nuclear outline, fine granular chromatin, and small nucleoli. Occasional intranuclear inclusions, coarse collageneous cytoplasmic filaments were observed. Many spindle‐shaped cells with similar nuclear findings were also seen. A cytologic diagnosis of a chordoid meningioma was suggested and histochemical and immunohistochemical studies were conducted on formalin‐fixed, paraffin‐embedded material. Immunohistochemically, the tumor cells showed diffuse and strong membranous and cytoplasmic staining for vimentin, epithelial membrane antigen (EMA) and faintly reactive with S‐100 protein but negative for pan‐neuroendocrine markers (i.e., NSE, chromogranin A, synaptophysin), cytokeratin AE1/AE3, smooth muscle actin, D2‐40, brachyury or class III beta‐tubulin. The proliferative index with MIB‐1 was less than 1%. The diagnosis of orbital intraosseous CM was confirmed based on cytopathologic, histopathological, immunohistochemical results, location of the tumor, and the lack connection to the duramater. We demonstrated here for the first time the cytopathological features of intraosseous CM with emphasis on differential diagnostic considerations. Diagn. Cytopathol. 2010; 38:818–821. © 2010 Wiley‐Liss, Inc.     

颈静脉孔区的解剖学结构与影像显示

目的:探讨颈静脉孔区正常解剖结构特点及影像学表现,为该区疾病诊断、手术治疗提供解剖学与影像学依据.方法:取10个成人头颅标本(20侧颈静脉孔)通过采用Fisch颞下窝手术入路进行解剖和观察,测量相关解剖学数据;采用MSCT与MR对10名健康自愿者进行头颅扫描,获取MSCT与MR影像表现,将测得数据进行统计学分析.结果:在20侧颈静脉孔中,有18侧(90%)的舌咽神经和迷走神经之间存在纤维性硬膜,颞突比较恒定,枕突少见,3侧(15%)有完整骨桥;舌咽神经、迷走神经、副神经都有很多根丝,迷走神经根丝可多达13条;右侧颈静脉球高度高于左侧,P<0.05.MSCT颅底层面可清晰显示颈静脉孔大小、形态及其内颞突、枕突、骨桥等骨性结构;MR3D-TOF法可显示颈内动脉、基底动脉、大脑后动脉等血管影像.结论:颈静脉孔区解剖结构复杂,通过颈静脉孔区的解剖学和影像学研究,能够为颈静脉孔区骨质消磨术和该区血管病变手术提供客观依据,从而降低该区手术对神经、血管的损伤,提高手术疗效.     

Is the cranial accessory nerve really a portion of the accessory nerve? Anatomy of the cranial nerves in the jugular foramen

The accessory nerve is traditionally described as having both spinal and cranial roots, with the spinal root originating from the upper cervical segments of the spinal cord and the cranial root originating from the dorsolateral surface of the medulla oblongata. The spinal rootlets and cranial rootlets converge either before entering the jugular foramen or within it. In a recent report, this conventional view has been challenged by finding no cranial contribution to the accessory nerve. The present study was undertaken to re-examine the accessory and vagus nerves within the cranium and jugular foramen, with particular emphasis on the components of the accessory nerve. These nerves were traced from their rootlets attaching to the spinal cord and the medulla and then through the jugular foramen. The jugular foramen was exposed by removing the dural covering and surrounding bone. A surgical dissecting microscope was used to trace the roots of the glossopharyngeal nerve (CN IX), vagus nerve (CN X) and accessory nerve (CN XI) before they entered the jugular foramen and during their travel through it. The present study demonstrates that the accessory nerve exists in two forms within the cranial cavity. In the majority of cases (11 of 12), CN XI originated from the spinal cord with no distinct contribution from the medulla. However, in one of 12 cases, a small but distinct connection was seen between the vagus and the spinal accessory nerves within the jugular foramen.     

颈静脉孔的应用解剖学

目的：为与颈静脉孔相关的影像诊断和临床治疗提供解剖学资料。方法：从颅底内、外面,对80具成年颅骨的颈静脉孔进行观测;并对20具成人尸头进行解剖,观察该区域神经血管解剖关系。结果：①62.3%右侧颈静脉孔较左侧大,15.9%左侧较大,21.8%两侧大小一致;②14.38%的颈静脉孔有骨桥,85.62%无骨桥;③颈静脉孔内、外侧缘距正中矢状面两侧的平均距离颅外均较颅内大：颅外分别为26.11mm和33.41mm,颅内分别为22.29mm和27.52mm。④XI脑神经多沿颈静脉孔前上缘,X、XI脑神经沿内侧缘出颅,两者被纤维索（占87.5%）或骨桥（占12.5%)隔开。⑤IX脑神经多经颈静脉孔外口前上缘向前下越过颈内动脉表面;IX脑神经经颈内静脉深面（占57.5%）或其浅面（42.5%)行向后下。结论：右侧颈静脉孔通常较左侧大,左右不对称;影像学观测该区域血管、神经应选择恰当的层面。     

Intracranial chondromyxoid fibroma extending into the jugular foramen

A case is reported of an intracranial chondromyxoid fibroma (CMF) in a 67 year old man. The tumor originated in the petrous part of the temporal bone and extended into the jugular foramen. Microscopically, the tumor showed a lobular appearance, and was composed of spindle or stellate cells in an abundant myxoid, chondroid stroma. Immunohistochemically, S-100 protein was positive in the tumor cells and myxoid stroma. Intracranial CMF, especially in an elderly person, is exceedingly rare. Clinical and pathological findings are presented with reference to the previously reported articles.     

Solitary fibrous tumor of the spinal nerve rootlet: report of a case mimicking schwannoma

We report a case of solitary fibrous tumor involving the spinal nerve root at the L1-L2 level in a 67-year-old man. The patient presented with lumbar pain and weakness in his right lower extremity. Histologically, the tumor was composed of a proliferation of monomorphous spindle cells in an abundant collagenous stroma; neither necrosis nor mitoses were evident. These cells were strongly immunoreactive with CD34, Bcl-2, CD99, and vimentin, but were negative with S100 protein, smooth muscle actin, and epithelial membrane antigen. Such an immunohistochemical profile was consistent with a solitary fibrous tumor of the spinal nerve rootlet and ruled out the main differential diagnoses, schwannoma and meningioma. The present case suggests that solitary fibrous tumor should be considered in differentiating spindle cell lesions of the spinal cord and nerve rootlet.     

Intracerebral schwannoma clinically and radiologically mimicking meningioma

A case of intracerebral schwannoma (ICS) occurring in a 33-year-old woman is presented. The patient's history of headache, numbness, tingling and the recent development of weakness of the right upper extremity with right facial droop began during pregnancy. Magnetic resonance imaging (MRI) showed a 4 x 2 x 2 cm heterogeneous, gadolinium-enhanced mass at the left frontoparietal junction, with peritumoral edema and a dural-based attachment. During her pregnancy, the mass increased in size. The surgically resected specimen consisted of lobulated, somewhat gelatinous soft tissue. Microscopically, the tumor demonstrated classic biphasic Antoni type A and B patterns, admixed with degenerative changes. Immunohistochemically, the neoplastic cells were positive for S-100 protein (diffuse and strong), CD34 (primarily in Antoni B areas), glial fibrillary acidic protein (GFAP; weak and diffuse) and calretinin (mainly in Antoni A areas), while none was positive for CD31, estrogen and progesterone receptors, bcl-2, or epithelial membrane antigen (EMA). Ultrastructurally, basal laminae and Luse bodies were identified. The differential diagnosis includes fibrous meningioma, solitary fibrous tumor, and ICS. Twenty-seven cases of ICS were reviewed in which the histological diagnosis was confirmed immunohistochemically or ultrastructually, and the cases were summarized (including the present case). A combined use of immunostains (S-100 protein, EMA, CD34, and maybe calretinin) is of great help in distinguishing ICS from its histological mimickers.     

Jugular foramen neurilemmoma mimicking an intra-axial brainstem tumor--a case report.

Jugular foramen neurilemmoma is frequently manifested as a jugular foramen syndrome or extraaxial mass. Neurilemmoma arising from the cranial nerves of the foramen, although rare, may be manifestated as an intracranial or extracranial mass lesion. When the tumor is located only in the intracranium, it is often misdiagnosed as an acoustic neurinoma or a brainstem tumor because of their similarity in clinical or radiological findings. We present a rare case of jugular foramen neurilemmoma with only intracranial extension with clinical and radiologic features of an intra-axial brainstem tumor.     

前庭小管外口的形态特点及其临床意义

目的：研究前庭小管的形态及毗邻关系,为经岩骨临床手术提供解剖学依据。方法：在32例（64侧）新鲜颅底标本上观察前庭小管的形状,并测量其长度及其到内听孔下后缘,下状窦前缘,岩骨嵴,颈静脉孔上缘的距离,对比双侧的差异,结果：前庭小管多为弧形（48％）,其次为S型（28％）,折线形最少,前庭小管长度及其到内听孔下后缘,乙状窦前缘,岩骨嵴,颈静脉孔上缘的距离平均值分别为：9．7,10．7,7,9．6,8．8和9．5毫米,其中到乙状窦和颈静脉孔的距离两侧有显著性差异,均以右侧较短,结论：前庭小管是经岩骨手术的重要解剖标志,国人和国外人种在解剖上存在一定差异,乙状窦前置和高颈静脉以右侧多见。     

Morphological characteristics of the cranial root of the accessory nerve

There has been the controversy surrounding the cranial root (CR) of the accessory nerve. This study was performed to clarify the morphological characteristics of the CR in the cranial cavity. Fifty sides of 25 adult cadaver heads were used. The accessory nerve was easily distinguished from the vagus nerve by the dura mater in the jugular foramen in 80% of 50 specimens. The trunk of the accessory nerve from the spinal cord penetrated the dura mater at various distances before entering the jugular foramen. In 20% of the specimens there was no dural boundary. In these cases, the uppermost cranial rootlet of the accessory nerve could be identified by removing the dura mater around the jugular foramen where it joined to the trunk of the accessory nerve at the superior vagal ganglion. The cranial rootlet was formed by union of two to four short filaments emerging from the medulla oblongata (66%) and emerged single, without filament (34%), and usually joined the trunk of the accessory nerve directly before the jugular foramen. The mean number of rootlets of the CR was 4.9 (range 2–9) above the cervicomedullary junction. The CR of the accessory nerve was composed of two to nine rootlets, which were formed by the union of two to four short filaments and joined the spinal root of the accessory nerve. The CR is morphologically distinct from the vagus nerve, confirming its existence. Clin. Anat. 27:1167–1173, 2014. © 2014 Wiley Periodicals, Inc.     

颈静脉孔的放射解剖学

对200侧正常颈静脉孔的X线影像和20侧尸头颈静脉孔进行了观测。颈静脉孔有单、双孔之分,左侧的单、双孔分别占86%和14%,右侧的分别占80%和20%。单孔的形态可分四种,双孔的间隔为骨桥。左、右侧颈静脉孔的面积分别为46mm~2和62mm~2。颈内静脉位于孔的后外侧部,舌咽神经位于前内侧部,迷走神经和副神经可位于前内侧部、后外侧部或二部交界处。     

Malignant spinal meningioma in a CD-1 mouse

Spontaneous meningiomas are extremely rare tumors in small laboratory animals, except in some strains of rats and in the B6C3F1 mouse. We report the case of a male CD-1 mouse in poor health condition, with severe apathy and partial paresis of hindlegs. No macroscopic lesion was noticed at necropsy. Microscopic examination revealed the presence of a malignant meningioma (approximately 3mm in diameter) at the distal lumbar level of the spinal cord, invading the vertebral canal, and bilaterally the ventral and dorsal nerve roots and the dorsal root ganglia. The tumor displayed highly cellular sheets of polygonal cells with a well-delineated, abundant, eosinophilic cytoplasm and scarce fibrovascular stroma; epithelioid and sarcomatous areas were also present. The mitotic activity was moderate. Tumor cells expressed vimentin immunoreactivity and were negative for periodic acid-Schiff (PAS), silver impregnation for reticulin, chromogranin A, glial fibrillary acidic protein (GFAP), cytokeratin (CK) and S-100 protein. The diagnosis of malignant spinal meningioma was based on the morphologic features of the neoplasm, the evidence of local invasion and the immunohistochemical results.     

Meningioma with granulofilamentous inclusions

The authors report a case of intracranial meningioma with granulofilamentous inclusions. A 50-year-old man had right trigeminal neuralgia due to trigeminal nerve compression by a petroclival tumor and received tumor resection. Microscopically, tumor cells containing eccentric nuclei and intracytoplasmic hyaline inclusions were arranged in sheets and whorls. The inclusions were negative for periodic acid-Schiff reaction. No histological anaplasia was seen. Immunohistochemistry showed epithelial membrane antigen reactivity on the cytoplasmic membrane. Immunoreactivity for vimentin was recognized in cytoplasm adjacent to inclusions. However, confocal laser microscopic study revealed immunoreactivity for vimentin even inside some inclusions. Ultrastructurally, interdigitation of cytoplasmic processes and desmosomes connecting adjacent cells were noted. Inclusions were composed of numerous fine osmiophilic granules attached by intermediates filaments. These findings were consistent with a meningioma with the granulofilamentous inclusions described earlier. The findings demonstrated by confocal laser microscopy and electron microscopy suggest that these granular materials may be the metabolic products of vimentin filaments.     

Case Report: Meningioma with Granulofilamentous Inclusions

The authors report a case of intracranial meningioma with granulofilamentous inclusions. A 50-year-old man had right trigeminal neuralgia due to trigeminal nerve compression by a petroclival tumor and received tumor resection. Microscopically, tumor cells containing eccentric nuclei and intracytoplasmic hyaline inclusions were arranged in sheets and whorls. The inclusions were negative for periodic acid-Schiff reaction. No histological anaplasia was seen. Immunohistochemistry showed epithelial membrane antigen reactivity on the cytoplasmic membrane. Immunoreactivity for vimentin was recognized in cytoplasm adjacent to inclusions. However, confocal laser microscopic study revealed immunoreactivity for vimentin even inside some inclusions. Ultrastructurally, interdigitation of cytoplasmic processes and desmosomes connecting adjacent cells were noted. Inclusions were composed of numerous fine osmiophilic granules attached by intermediates filaments. These findings were consistent with a meningioma with the granulofilamentous inclusions described earlier. The findings demonstrated by confocal laser microscopy and electron microscopy suggest that these granular materials may be the metabolic products of vimentin filaments.     

Morphometric study of jugular foramen in adult South Indian skulls

IntroductionThe jugular foramen lies between the occipital bone and the petrosal portion of the temporal bone. It allows the passage of important nervous and vascular vein and inferior petrosal sinus. Glomic tumors, schwannomas, metastatic lesions and infiltrating inflammatory processes are associated with this foramen, which can account for injuries of related structures. Morphometric study of this foramen will serve as guide for imaging and operative procedures in the jugular foramen region.Material and methodsOne hundred and sixteen dry adult skulls of unknown sex of south Indian origin were utilized for this study. Following dimensions of the foramen were measured with the help of a digital vernier caliper: i) Maximum dimension along the long axis; ii) Maximum dimension perpendicular to the long axis; iii) Maximum height of dome of jugular fossa and iv) Distance of stylomastoid foramen from lateral margin of jugular foramen. The minimum distance of stylomastoid foramen from the lateral margin of the foramen was also measured.ObservationsThe findings of the present study bring forth some important facts as follows: On an average, all the dimensions measured were more on the right side. The jugular fossa showed great variability ranging from total absence of fossa to deep excavation anterolaterally forming a large fossa with the well-defined roof.ConclusionThese observations call for further studies on variability of jugular fossa and its possible implications. The distance of the stylomastoid foramen from the jugular foramen will serve as guide for operating surgeons using infratemporal approach during skull base surgeries.     

Peripheral nerve sheath differentiation in malignant soft tissue tumours: an ultrastructural and immunohistochemical study.

Thirteen soft tissue sarcomas with ultrastructural evidence of nerve sheath differentiation were investigated by immunohistochemistry. Three arose in a major nerve or nerve trunk and four patients had von Recklinghausen's neurofibromatosis. Ultrastructurally, 10 cases showed variable differentiation towards Schwann cells, two resembled perineurial cells and one tumour had features suggestive of both cell types. Immunostaining for S-100 protein was positive in eight Schwann cell tumours, negative in the other two Schwann cell tumours and negative in those with perineurial-like cells. No cases demonstrated epithelial membrane antigen, so that the existence of perineurial cells in malignant nerve sheath tumours remains immunohistochemically unsubstantiated; it may be that the perineurial-like cells are merely incompletely differentiated Schwann cells, with nerve sheath differentiation manifesting a continuous spectrum. Leu 7 was detected in four Schwann cell tumours, three of which were ultrastructurally well differentiated. Cytokeratin and desmin were demonstrated only in an undifferentiated pleomorphic area of one Schwann cell tumour. Electronmicroscopy can aid diagnosis by revealing nerve sheath differentiation in malignant soft tissue tumours without demonstrable S-100 protein.     

Microcystic meningioma in a dolphin (Delphinus delphis): immunohistochemical and ultrastructural study

A wild common dolphin was found stranded on the French Atlantic coast. At necropsy, an intracranial grey- to tan-coloured mass (7 x 5 x 4 cm) was found at the right cerebellopontine angle, compressing the right cerebellar hemisphere, the brainstem and the occipital lobe of the right cerebral hemisphere. Microscopically, the tumour was composed of small lobules of polygonal to elongated neoplastic cells with multifocal areas of stellate and vacuolated cells. Neoplastic cells strongly expressed vimentin, S-100 protein and neuron-specific enolase. They were rarely positive for cytokeratin. Ultrastructurally, the neoplastic cells displayed all the diagnostic features of meningiomas and in some areas showed long cytoplasmic processes delimiting extracellular spaces. The immunohistochemical and ultrastructural features were consistent with the histopathological diagnosis of a microcystic meningioma. This is the first report of a meningioma in dolphins or in any other cetacean species.