MRI Differentiation Diagnosis of Occupying Lesions in Cerebellopontine Angle Area

Objective： To explore the value of magnetic resonance imaging （MRI） in diagnosis of occupying lesions in cerebellopontine angle area. Methods： MRI records of 78 patients with pathologically confirmed occupied lesions in cerebellopontine angle area were analyzed. Results： Of the 78 cases, 48 （61.5%） were unilateral acoustic neuroma, 5 （6.4%） were bilateral acoustic neuroma, 12 （15.4%） were meningioma, 4 （5.1%） were trigeminal neuroma, 3 （3.8%） were lipoma, 2 （2.6%） were melanoma, and 1 （1.3%） was medulloblastoma. According to the anatomic site, tumor lesion character, and MRI signal, the majority of cerebellopontine angle area tumors were diagnosed accurately. Conclusion： MRI plays an important role in diagnosis of occupying lesions in cerebellopontine angle area.

Malignant meningioma of the cerebellopontine angle in a 2-year-old girl:a case report and literature review

Meningioma is a common intracranial tumor in adults.Pediatric cases account for approximately 1.5% of all intracranial meningiomas,and very few cases show malignant histological features.Primary pediatric malignant meningioma in the cerebellopontine angle is extremely uncommon.Herein,we report a 2-yearold girl with malignant meningioma in the cerebellopontine angle.The clinical features,diagnosis,and treatment protocol are discussed.

Clinical Application of Quantitative Nursing for Lower Cranial Nerves Injury after Cerebellopontine Angle Tumors

Objective: To retrospectively analyze the clinical utility of quantitative nursing measures of 10 cases of lower cranial nerves injury after cerebellopontine angle tumors surgery to provide the experience for improving the recovery rate and living quality of these patients. Methods: The clinical data of 10 cases of lower cranial nerves injury after cerebellopontine angle tumors surgery was analyzed. For problems such as dysphagia and dyspnea of these patients, the nursing care focused on strict monitoring, timely oxygen inhalation nursing, posture nursing, ventilator nursing, swallowing function training, etc. Results: After received quantitative care, 10 patients with lower cranial nerves injury after cerebellopontine angle tumors surgery were recovered well, and their symptoms such as dysphagia and dyspnea were gradually improved and safely discharged. Conclusion: Lower cranial nerves injury is one of the serious complications after removal of cerebellopontine angle tumors, which impacts the life and health of patients. Caregivers should accurately understand and analyze the symptoms, and quantitative and targeted nursing measures for posterior cranial nerves injury are helpful in the postoperative rehabilitation of patients and improve their living quality.

An adult case of medulloblastoma in the cerebellopontine angle extending to the supratentorial area

Medulloblastoma is an undifferentiated embryonic neuroepithelial tumor. It is a rare tumor in the central nervous system, with an even rarer occurrence during adulthood. It may develop at an atypical and uncommon site, such as the cerebellopontine angle （CPA）, and such tumors rarely present with supratentorial extension. The present study reports an adult case of medulloblastoma in the CPA extending to the supratentorial area. The patient presented with complaints of headache, vertigo, hearing difficulty in the left ear, nausea/vomiting, and unsteady gait. Disequilibrium began 4 weeks earlier. Examination revealed normal cranial nerves, and computed tomography showed a hyperdense lesion, with a heterogeneously enhancing mass, in the left CPA region. The patient underwent a nearly total excision of the lesion in the CPA region. Histopathological examination confirmed medulloblastoma, WHO grade IV. Postoperatively, the patient received radiotherapy and remained asymptomatic for 30 months. However, he received two more surgeries for relapse and progression of medulloblastoma and eventually died. A CPA medulloblastoma with supratentorial extension is relatively rare in the clinic.

Meningeal melanocytoma in the cerebellopontine angle:A rare case report and review of the literature

Primary meningeal melanocytoma(MM)in the cerebellopontine angle(CPA)region is an extremely rare neoplasm that originates from the melanocytes in the leptomeninges.These lesions are usually misdiagnosed as they mimic other common CPA lesions through their nonspecific presenting symptoms,signs,and radiological characteristics.Here,we report a 47-year-old Chinese female patient who presented with a 1-month history of the right-sided tongue numbness and 1-week history of the right-sided face numbness that had been worsening for 2 days.The tumor,in the right CPA region,showed a slight isointensity on T1-weighted image and mixed signal intensity on T2-weighted image.The clinical presentation,surgical treatment,and pathologic characteristics were determined.The tumor was microsurgically resected and gross-total resection was achieved.The tumor revealed a solid,capsulated,brown-black lesion.Immunohistochemistry showed that the tumor cells were positive for human melanoma black-45(HMB-45),melanoma antigen(MelanA),S100,SOX10,and BRAF,confirming the final diagnosis of meningeal melanocytoma.Ultimately,no signs of radiological local recurrence were observed during the two-year follow-up.Collectively,meningeal melanocytoma is difficult to distinguish from common tumors in the CPA region before operation due to the lack of specificity in imaging and symptoms.Complete surgical resection is the best therapeutic option for this tumor.Although the tumor is commonly considered as a benign lesion,recurrence and metastasis are common,and pathogenesis remains unclear.

Cerebellopontine Angle Epidermoid Cyst: Case Report

Epidermoid cysts are rare congenital tumors of the central nervous system (CNS), histologically benign and slow- growing lesions. Their frequency among primitive intracranial tumors is about 1% and they account for 40% of all intracranial epidermoid of the cerebellopontine angle (CPA);there they constitute the third most frequent neoplasm (5%), after acoustic neuromas and meningiomas. We report the case of a patient with a paucisymptomatic epidermoid cyst of the CPA.

Clinical Benefits of Facial Nerve Monitoring during Cerebellopontine Angle Surgery

Background: The surgery of cerebellopontine angle tumours has remarkably progressed over the last 2 decades due to improved microsurgical techniques. The primary operative goals are microscopic total removal of the tumour while securing the adjacent cranial nerves. Facial Nerve plays a critical role in facial muscles function and one’s cosmetic appearance, and its weakness can have profound implications on a patient’s quality of life. Aim of the Study: To assess the impact of monitoring techniques on the preservation of facial nerve function during cerebellopontine angle tumours surgery. Patients and Methods: This is a prospective study. This study was conducted on 30 cases (2 groups, each had 15 patients) with CPA lesions that had undergone surgical excision of these lesions performed by retrosigmoid approach (Group A: the patients were operated under continuous intraoperative facial nerve monitoring (IOFNM) and Group B: the patients were operated without IOFNM). They were operated upon in neurosurgery departments at Al-Azhar university hospitals between August 2019 and August 2021. Results: This study showed that excellent facial nerve function (HB Grade I and II) was higher in group A than group B, immediately and at 6-month post op (80% and 93% VS 53.3% and 66.7%). Intermediate (HB Grade III and VI) and Poor (HB Grade V and VI) facial nerve function was higher in group B than group A;both immediately and 6-month postop (46.7% and 33.3% VS 20% and 6.6%). However, no statistically significant P-Value between both groups. Conclusion: We concluded that IOFNM can help, but cannot guarantee, the preservation of facial nerve. Furthermore, it is merely a technical adjunct and does not replace surgical skills, knowledge of anatomy and experience.

Gastrointestinal Symptoms—A Rare Complication of Untreated CPA Tumor

Cerebellopontine angle (CPA) lesions account for up to 10% of all intracranial tumors. Most CPA tumors are benign, but can cause nerve damage or compress the surrounding structures if left untreated. The typical presentation is with adult-onset sensorineural hearing loss or non-pulsatile tinnitus. In some patients, this goes unnoticed, and presentation is delayed until the lesion is much larger and presents with symptoms related to mass effect. We present the case study of 63 years old gentleman, who had suspected left CPA lesion on CT head done few years ago for dizziness and left-sided facial numbness. MRI could not be done at that time due to his MRI incompatible pacemaker leading to delay in his management eventually causing loss of patient to the follow up. He later developed progressive difficulty in walking which was initially attributed to as secondary to vasovagal syncope and postural hypotension. He eventually presented to us with intractable nausea and vomiting, worsening headache and ataxia. He had an urgent CT head which showed significant growth in the lesion with compression of the surrounding structures and obstructive hydrocephalus. He was given steroids which improved his nausea and vomiting, followed by undergoing surgery in regional center leading to significant improvement in his gait within few days of surgery. He unfortunately continued to have a degree of ataxia and facial numbness. This case illustrates a rare presentation of CPA tumor with symptoms of nausea and vomiting as a result of mass effect of the growing tumor. In addition, this review also shows the importance of regularly following up the patients with suspected CPA lesions on initial scans which will help with identifying the increase in size of lesion promptly and potentially preventing advanced complications of CPA tumors. We suggest regular monitoring of these patients to timely manage the lesion and avoid the potential life-threatening complications.

桥小脑角肿瘤继发性三叉神经痛的临床病理特征

目的:桥小脑角(cerebellopontine angle,CPA)肿瘤是继发性三叉神经痛(trigeminal neuralgia,TN)的常见病因,其位置隐蔽,进展缓慢,难以早期发现。本研究旨在探讨CPA肿瘤继发性TN患者的临床病理特征,提高对继发性TN诊治的认识。方法:回顾性分析中南大学湘雅医院2017年1月1日至2022年12月31日收治的116例CPA肿瘤继发TN患者的临床资料和病理结果,分析肿瘤病理类型与临床表现、肿瘤部位、手术方式及疗效的关系。结果:本组病例中95.7%(111/116)为良性肿瘤,3.4%(4/116)为恶性肿瘤,0.9%(1/116)为交界性肿瘤,良性肿瘤以胆脂瘤、脑膜瘤、神经鞘瘤多见。46.6%(54/116)的患者表现为单纯TN,53.4%(62/116)出现其他伴随症状,这取决于不同类型肿瘤的生长部位、生长速度等因素。本组病例手术全切率在90%以上,41.4%(48/116)的患者在切除肿瘤后同期行微血管减压,其中神经鞘瘤占比最高。手术治疗总体有效率达93.9%,神经鞘瘤的有效率高于胆脂瘤、脑膜瘤(均P<0.05);胆脂瘤的复发率显著高于脑膜瘤、神经鞘瘤(均P<0.05)。结论:CPA肿瘤是继发性TN的主要病因,以良性肿瘤多见,恶性肿瘤虽少但容易被漏诊,早期诊治对预后影响很大。不同类型肿瘤在临床症状、手术方式、疗效等方面有所不同,手术策略需兼顾肿瘤切除程度及神经功能保护,必要时行微血管减压术。

桥脑小脑角区脂肪瘤的诊治分析

目的探讨桥脑小脑角区脂肪瘤的临床特点、治疗方法及其疗效。方法回顾性分析2009年1月至2022年1月收治的6例桥脑小脑角区脂肪瘤的临床资料。结果6例均出现患侧听力减退,伴眩晕、面神经功能障碍及面部疼痛各1例;MRI呈特异性短T1、长T2信号,CT呈低密度。4例手术治疗,2例保守观察。术后除听力下降以外的症状均得到缓解。出院后随访10~151个月,未出现疾病进展。结论桥脑小脑角区脂肪瘤是先天性良性病变,影像表现较为特异;如出现明显临床症状,则可手术治疗,但手术难以保留残存听力,术中实现减压即可,不宜追求肿瘤切除程度。

桥小脑角脑膜瘤的显微外科治疗及疗效影响因素分析

目的探讨桥小脑角(CPA)脑膜瘤的显微外科治疗策略,并分析影响手术疗效的因素。方法回顾性分析南京医科大学第一附属医院神经外科2009年5月至2019年4月收治的137例CPA脑膜瘤患者的临床资料。采用Simpson分级评估肿瘤切除程度,以Karnofsky功能状态评分(KPS)评估预后,应用单因素分析探讨影响肿瘤切除程度的因素。结果137例患者中,132例行枕下乙状窦后入路,5例行颞下+乙状窦后入路。SimpsonⅠ~Ⅱ级切除122例(89.1%),Ⅲ级切除11例(8.0%),Ⅳ级切除4例(2.9%)。术后患者均获得随访,随访时间为(72.4±20.8)个月。随访期间,肿瘤复发2例(1.7%),进展1例(6.7%)。末次随访时KPS评分(92.3±13.1)分,高于出院时的(86.9±9.4)分和术前的(75.8±10.3)分(均P<0.001)。单因素分析结果表明,肿瘤的分型(P=0.013)、大小(P=0.023)、瘤周水肿(P=0.005)、瘤周蛛网膜不完整(P=0.030)为影响肿瘤全切的因素。结论经枕下乙状窦后入路可以切除大多数CPA区脑膜瘤。肿瘤体积较小、瘤周蛛网膜界面清晰、无瘤周水肿、非联合型脑膜瘤术中易获得全切。

经乙状窦后入路CPA区内窥镜解剖学观察

目的通过神经内窥镜下桥小脑角区的解剖,为内窥镜辅助下该区域病变的手术治疗提供了解剖学依据,并探讨其临床应用价值。方法在15具福尔马林固定的成人尸头标本和1具新鲜成人尸头标本上进行桥小脑角区的窥镜解剖学研究,在窥镜下分区并测量有关数据。结果内窥镜能清晰地显示颅神经及其附近的血管,桥小脑角区从头侧至尾侧被血管神经束分为三个间隙:间隙Ⅰ、间隙Ⅱ、间隙Ⅲ,其中间隙Ⅰ又分为Ⅰa、Ⅰb亚间隙(Subspace),间隙Ⅰ、间隙Ⅱ是内窥镜主要的观察通道。结论神经内窥镜可明显改善深部术野的照明效果和显微解剖结构的识别,对显微外科手术起重要的辅助作用。

术中耳蜗电图监测在脑桥小脑角区胆脂瘤切除术中的应用

目的 分析术中耳蜗电图(ECochG)监测信息与术后美国耳鼻咽喉头颈外科学会(AAO-HNS)听力功能分级及听力残疾量表(HHI)之间的关系。方法 回顾性分析中日友好医院神经外科2019年3月—2022年3月收治的86例脑桥小脑角(CPA)区胆脂瘤患者的临床资料。所有患者均采用乙状窦后入路切除CPA区胆脂瘤,在术中ECochG的监测下完成肿瘤的完整切除。依据术中ECochG监测信息中动作电位(AP)波幅下降>30%与否分为两组,AP波幅下降>30%组和AP波幅下降≤30%组,分析两个组与术后听力功能障碍及听力残疾程度的关系。结果 AP波幅下降>30%组患者术后存在听力功能障碍,并且在随访3个月、1年和2年后,患者的听力功能障碍持续存在,且有统计学差异(P<0.001)。AP波幅下降>30%组患者术后存在不同程度的听力残疾,在随访3个月、1年和2年后,患者的HHI情绪相关(subtotal-E)及社会相关(subtotal-S)的听力残疾持续存在,有统计学差异(P<0.001);HHI subtotal-E及subtotal-S相关的残疾程度会逐渐加重,有统计学差异(P<0.05)。结论 术中AP波幅下降>30%的患者在CPA区胆脂瘤术后存在永久听力障碍,其术后subtotal-E及subtotal-S相关的听力残疾程度会逐渐加重。

CPA表皮样囊肿继发三叉神经痛的临床特点及危险因素分析

目的探讨由CPA表皮样囊肿导致的继发性三叉神经痛的临床特点与手术疗效,以及其与原发性三叉神经痛的差别。方法回顾分析周口市中心医院2015-01—2018-07 12例由CPA表皮样囊肿导致的继发性三叉神经痛的临床资料,同时分析224例特发性三叉神经痛的临床资料。均经乙状窦后入路显微手术切除肿瘤。结果单因素分析显示继发于表皮样囊肿的三叉神经痛患者年龄均较轻,年龄(46.3±8.5)岁,同时继发性三叉神经痛的病程通常较短。肿瘤全切10例,次全切除2例。10例疼痛症状消失,2例术后3个月疼痛症状消失,随访3个月～3a疼痛无复发。术后住院期间发生短期患侧面部麻木1例,面部感觉减退5例,面瘫4例(House-BrackmannⅡ-Ⅲ级),听力下降1例,随访3个月后症状均恢复,所有患者术后无死亡及重残。结论 CPA表皮样囊肿继发三叉神经痛多数由于CPA区占位直接或间接压迫神经所导致,早期病变小,症状发作年龄较小,症状持续时间短,多数易于切除,手术疗效满意。

显微手术切除CPA区脑膜瘤的术后护理体会

目的探讨显微手术切除桥小脑角(CPA)脑膜瘤术后护理的方法和特点。方法总结34例桥小脑角脑膜瘤显微手术治疗的护理体会。结果绝大多数患者临床症状明显缓解,预后良好,无由于护理不当造成的并发症。结论桥小脑角脑膜瘤术后护理对患者的康复是必要的。

桥小脑角区占位性病变MRI与CT影像学特征及诊断价值

目的分析桥小脑角(CPA)区占位性病变患者MRI、CT影像学特征及诊断的临床价值。方法选取2020-05—2023-11内江市中医医院收治的90例CPA区占位性病变患者为研究对象,所有患者经手术病理确诊并接受MRI及CT检查,分析不同检查方法的影像学特征,探究MRI及CT在CPA区占位性病变患者临床诊断中的应用价值。结果MRI检查对CPA区占位性病变的总检出率(97.78%)高于CT检查(88.89%),差异有统计学意义(P<0.05)。MRI检查中听神经瘤、脑膜瘤、三叉神经瘤、表皮样囊肿、血管母细胞瘤T_(1)WI均以低信号为主(分别占65.52%、69.23%、77.78%、80.00%、100.00%),T_(2)WI均以高信号为主(分别占56.90%、76.92%、88.89%、80.00%、100.00%),增强后多呈明显均匀强化。CT检查中听神经瘤、脑膜瘤、三叉神经瘤、表皮样囊肿、血管母细胞瘤病灶呈低密度、高密度或混合密度影(分别占43.86%、81.82%、66.67%、80.00%、100.00%),增强后多呈均匀或不均匀强化,但能显示病灶病变特征。结论MRI和CT有各自特征性的影像学表现,MRI对CPA区占位性病变的检出率更高,对其术前定性诊断具有重要价值。

Air—CT扫描对CPA区蛛网膜粘连的诊治作用

本文报道了我院采用 air-CT 扫描诊断 CPA 及 IAC 病变时,发现空气对 CPA 区蛛网膜粘连有分离治疗作用,通过对35例病人随访及临床验证认为:air-CT 扫描是诊断蛛网膜粘连最简便及可靠的方法。该检查不仅可明确有无粘连,粘连的程度、范围、还可了解该区神经血管的关系、同时对粘连起到一定的治疗作用。这是其它任何检查法所无法比拟的。

Air－CT扫描对CPA区蛛网膜粘连的诊治作用

本文报道了我院采用Ａｉｒ－ＣＴ扫描诊断３５例ＣＰＡ蛛网膜粘连并由此探索出一种较好治疗方法的经验。认为：Ａｉｒ－ＣＴ扫描是诊断ＣＰＡ区蛛网膜粘连最简便、可靠的方法。该检查不仅可明确有无粘连、粘连的程度、范围，还可了解该区神经血管的关系，同时对粘连起到一定的治疗作用．据Ａｉｒ－ＣＴ检查结果采用ＣＰＡ充气法辅以药物治疗对粘连能起到长期稳定的治疗效果，该治疗法还可重复进行．

Air-CT扫描检查CPA区血管神经接触——附43例扫描诊断分析

本文总结了95例CPA区air-CT检查诊断血管神经接触(NVC)43例的体会。认为在表现为后颅凹神经症状的CPA区病变中,以NVC发病率最高,是引起相应症状的原因。用air-CT检查可明确有无NVC,NVC发生的部位、程度及合并症,为临床手术提供依据。同时该文还讨论了NVC是正常或病理性以及引起症状的机理。

Anatomic structural study of cerebellopontine angle via endoscope

Background Minimally invasive surgery in skull base relying on searching for possible anatomic basis for endoscopic technology is controversial. The objective of this study was to observe the spatial relationships between main blood vessels and nerves in the cerebellopontine angle area and provide anatomic basis for lateral and posterior skull base minimally invasive surgery via endoscopic retrosigmoid keyhole approach.Methods This study was conducted on thirty dried adult skulls to measure the spatial relationships among the surface bony marks of posterior cranial fossa, and to locate the most appropriate drilling area for retrosigmoid keyhole approach. In addition, we used 10 formaldehyde-fixed adult cadaver specimens for simulating endoscopic retrosigmoid approach to determine the visible scope.Results The midpoint between the mastoid tip and the asterion was the best drilling point for retrosigmoid approach. A hole centered on this point with the 2.0 cm in diameter was suitable for exposing the related structures in the cerebellopontine angle. Retrosigmoid keyhole approach can decrease the pressure on the cerebellum and expose the related structures effectively which include facial nerve, vestibulocochlear nerve, trigeminal nerve, glossopharyngeal nerve, vagus nerve, accessory nerve, hypoglossal nerve, anterior inferior cerebellar artery, posterior inferior cerebellar artery and labyrinthine artery, etc.Conclusions Exact location on endoscope retrosigmoid approach can avoid dragging cerebellum during the minimally invasive surgery. The application of retrosigmoid keyhole approach will extend the application of endoscopic technology.