MRI在三叉神经痛和半侧面肌痉挛病因诊断中的价值

目的 探讨MRI在诊断三叉神经痛与半侧面肌痉挛中的价值.方法 将51例三叉神经痛与23例半侧面肌痉挛患者的术前MRI资料与手术结果进行对照分析.结果 ①74例患者中,MRI诊断患侧桥小脑角胆脂瘤8例,听神经瘤7例,三叉神经瘤4例,脑膜瘤3例,患侧神经微血管压迫49例(66.21％),MRI未见异常者3例(4.05％);②手术病理结果:胆脂瘤8例,听神经瘤7例,三叉神经瘤4例,脑膜瘤3例,三叉神经或面神经根部异常血管压迫者46例(62.16％),术中未见异常者6例(8.11％).结论 MRI在三叉神经痛和半侧面肌痉挛病因诊断中具有很高价值,是术前首选的检查方法.     

MR增强检查在桥小脑角肿瘤的诊断价值

目的探讨MRI增强检查诊断桥小脑角肿瘤的价值.方法研究68例手术和病理证实的桥小脑角肿瘤的资料,其中听神经瘤34例,三叉神经瘤5例,脑膜瘤20例,胆脂瘤9例.所有病人均作了增强前后的MR扫描,包括轴位、矢状位和冠状位.结果34例听神经瘤中,23例增强呈结节-环状、多环状、花环状肿块,囊变率68%;11例呈均匀肿块;34例显示面听神经束增粗强化与肿瘤相连,其中呈"荸荠”征15例,为听神经瘤的典型征像.5例三叉神经瘤强化呈结节-环状、或多环状3例,哑铃状2例,5例患侧三叉神经均显示不清,同侧面听神经受压.20例脑膜瘤中度强化均匀肿块;"脑膜尾”征11例,同侧面听神经束鞘膜强化、不增粗5例.9例胆脂瘤长T2、长T1与脑脊液一致,T1低信号中有比脑脊液信号稍高的组织,无强化表现,病变沿蛛网膜下腔扩展,基底动脉包埋5例.结论MRI增强检查能显示听神经瘤、三叉神经瘤、脑膜瘤、胆脂瘤的特征表现,诊断桥小脑角肿瘤有独特的价值.     

桥小脑角区肿瘤的MRI诊断

目的探讨桥小脑角区肿瘤的MRI表现及特征,提高对桥小脑角区肿瘤的定性诊断水平。方法34例经手术和病理证实的桥小脑角区肿瘤,其中听神经瘤20例,脑膜瘤4例,三叉神经瘤3例,血管母细胞瘤2例,胆脂瘤、蛛网膜囊肿、动脉瘤、胶质瘤及转移瘤各1例。在静注Gd-DTPA前后均经SE,FSE序列磁共振成像。结果听神经瘤,脑膜瘤,三叉神经瘤为桥小脑角区最常见的肿瘤,该区肿瘤大部分有特征性MRI表现,术前定位、定性准确率分别为96.9%,94.1%。结论MRI在桥小脑角区肿瘤影像诊断中具有不可比拟的优势,可作为桥小脑角区肿瘤术前的首选检查方法。     

桥小脑角区肿瘤的MRI诊断和鉴别诊断

目的 :探讨桥小脑角区肿瘤MRI的表现及特征。材料和方法 :分析 193例资料完整 ,均经手术和病理证实的桥小脑角区肿瘤 ,其中听神经瘤 135例 ,三叉神经瘤为 30例 ,脑膜瘤 12例 ,胆脂瘤 4例 ,蛛网膜囊肿 2例 ,动脉瘤 1例 ,血管母细胞瘤 4例 ,脉络丛乳头状瘤 3例 ,海绵状血管瘤 1例 ,转移瘤 1例。结果 :桥小脑角区肿瘤中 ,脑外肿瘤 95 .3% ,脑内肿瘤 4.7% ;良性肿瘤占 98.4% ,恶性肿瘤占 1.6%。发生于桥小脑角区的前三位肿瘤分别为听神经瘤 69.9% ,三叉神经瘤 15 .5 % ,脑膜瘤 6.2 % ,该区肿瘤大部分有特征性MRI表现 ,术前定位、定性诊断准确率分别为 10 0 %、96.4%。结论 :MRI是检查桥小角区肿瘤的首选方法 ,对桥小脑角区肿瘤诊断和鉴别有重要价值     

桥小脑角区肿瘤的磁共振成像诊断

目的：探讨桥小脑角区肿瘤的磁共振成像（MRI）的影像学表现及鉴别诊断,以提高其诊断水平。方法总结分析经影像学及手术病理证实的桥小脑角区肿瘤共33例。其中听神经瘤14例,三叉神经瘤8例,脑膜瘤2例,胆脂瘤3例,蛛网膜囊肿4例,恶性肉芽肿1例,颈静脉球瘤1例。所有患者均行MRI平扫及增强扫描,部分病例结合CT扫描。总结分析肿瘤的形态、大小、生长方式、信号特征及强化方式。结果桥小脑角区的肿瘤以听神经瘤占首位,其次为三叉神经瘤、胆脂瘤、蛛网膜囊肿、脑膜瘤。还有一些少见的肿瘤,诸如恶性肉芽肿、颈静脉球瘤等。结论桥小脑角区肿瘤MRI表现各具有不同特性,了解这些特征有助于诊断及鉴别诊断,为临床治疗及手术提供依据。     

桥小脑角区肿瘤及肿瘤样病变的CT诊断

目的：探讨CT对桥小脑角区肿瘤及肿瘤样病变的诊断价值。方法：回顾性分析经手术病理证实的桥脑小脑角区肿瘤及肿瘤样病变的CT特征。其中听神经瘤9例、胆脂瘤4例、脑膜瘤3例、耳源性脑脓肿5例、三叉神经瘤1例。结果：各种肿瘤的CT特征，随其种类而不同，如听神经瘤均位于内听道开口处，呈等或低密度团块，轻度均匀或环状强化。胆脂瘤呈球形或扁平形，球形位于硬膜外，密度不均，壁有钙化。扁平形位于蛛网膜下腔， 边缘清楚，均匀低密度。脑膜瘤均具有典型脑膜瘤特征，明显强化。耳源性脑脓肿周边有明显水肿、囊壁清晰，囊内呈均匀低密度。三叉神经瘤跨中后颅窝伴岩锥尖骨质破坏。结论：桥脑小脑角区肿瘤各具特点，CT能提供明确诊断。     

桥小脑角区肿瘤的MRI诊断

目的：分析桥小脑角区肿瘤的ＭＲＩ 表现,提高桥小脑角区肿瘤的ＭＲＩ 诊断准确率。材料和方法：搜集一组经手术及病理证实的桥小脑角区肿瘤４５ 例,全部行ＭＲＩ 平扫及增强检查。结果：本组４５ 例中听神经瘤１８ 例,脑膜瘤８ 例,三叉神经瘤６ 例,胆脂瘤３ 例,血管母细胞瘤４ 例,海绵状血管瘤４ 例,脊索瘤２ 例。肿瘤位于左侧桥小脑角区占６９ ％ ,位于右侧桥小脑角区占３１ ％ 。８７ ％ 的肿瘤呈园形或类园形,轮廓较清晰,占位效应明显,在Ｔ１ ＷＩ上多呈低等信号,Ｔ２ ＷＩ 上多呈高信号,增强后呈明显均匀强化。但各种肿瘤又有其特征性ＭＲ 改变,如三叉神经瘤跨中后颅窝生长,胆脂瘤沿脑池生长,听神经溜,三叉神经瘤,血管母细胞瘤多见囊变、坏死,海绵状血管瘤多见出血,脑膜瘤、脊索瘤有不规则钙化,多数脑膜瘤增强后见脑膜尾征。ＭＲＩ 对桥小脑角区肿瘤的检出率、定位率、定性率分别为１００ ％ 、１００ ％ 、９０ ％ 。结论：ＭＲＩ 对桥小脑角区肿瘤的诊断及鉴别诊断有重要价值。     

桥小脑角区肿瘤的MRI诊断和鉴别诊断

目的：分析桥小脑角区肿瘤的MRI表现和特征，提高桥小脑角区肿瘤的MRI诊断准确率。材料和方法：收集临床资料完整、经手术和病理证实的桥小脑角区肿瘤36例，全部行MRI平扫及增强检查。结果：听神经瘤16例，三叉神经瘤7例，脑膜瘤6例，胆脂瘤4例，蛛网膜囊肿2例，血管母细胞瘤1例。桥小脑角区肿瘤大部分有其特征性表现。结论：MRI对桥小脑角区肿瘤的诊断和鉴别诊断具有重要价值。     

桥小脑角区肿瘤的MRI诊断

目的：探讨桥小脑角区肿瘤MRI的表现及特征。材料和方法：分析297例资料完整、均经手术和病理证实的桥脑角区肿瘤。其中听神经瘤184例，三叉神经瘤39例，脑膜瘤27例，胆脂瘤13例，蛛网膜囊肿4例，动脉瘤1例，血管母细胞瘤6例，脉络丛乳头状瘤3例，海绵状血管瘤5例，转移瘤3例，脊索瘤3例。结果 桥小脑角区肿瘤中，脑外肿瘤93．8％，脑内肿瘤6．2％，发生于桥小脑角区的前三位肿瘤分别为听神经瘤63．6％，三叉神经瘤13．3％，脑膜瘤9．2％。该区肿瘤大部分具有特征性MRI表现。术前定位定性诊断准确率分别为100％、96．4％。结论：MRI是检查桥脑角区肿瘤的首选方法，对桥小脑角区肿瘤诊断和鉴别诊断有重要价值。     

桥小脑角区占位病变的MRI诊断及鉴别诊断

目的:探讨桥小脑角区(CPA)占位病变MR诊断及鉴别诊断价值。方法:搜集收治经手术和病理证实的桥小脑角区肿瘤患者91例,回顾性分析其MR表现。结果:听神经瘤64例,脑膜瘤17例,三叉神经瘤5例,表皮样囊肿3例,颈静脉球瘤1例,血管母细胞瘤1例。结论:MRI能较好地对CPA区占位病变作出诊断及鉴别诊断。     

3.0T磁共振断层血管成像对三叉神经痛和面肌痉挛血管神经压迫的诊断价值

目的 探讨3.0T磁共振断层血管成像(magnetic resonance tomographic angiography, MRTA )对三叉神经痛和面肌痉挛血管神经压迫的诊断价值. 方法 临床诊断的三叉神经痛52例,面肌痉挛9例,共61例.61例均行3.0T磁共振断层血管造影成像( MRTA),利用原始图像进行斜矢状位和冠状位重建,从3个方位观测血管神经的关系,并与手术结果进行对照. 结果 52例三叉神经痛中,MRTA显示46例存在三叉神经血管压迫或接触,6例无压迫.9例面肌痉挛MRTA显示面神经均有微血管跨越或压迫.手术结果显示52例三叉神经痛中45例存在三叉神经血管压迫或接触,6例无压迫,1例为囊肿;9例面肌痉挛均有微血管压迫.MRTA诊断阳性率为90.2%、敏感性为 96.4%、特异性为80%. 结论 3.0T超高场强下进行MRTA,对发现三叉神经痛和面肌痉挛血管神经压迫有重要诊断价值.     

Vascular anomalies of the cerebellopontine angle

Vascular anomalies of the cerebellopontine angle are rare compared to tumors in this area. Irritation of the trigeminal, facial, or vestibulocochlear nerve may cause trigeminal neuralgia, hemifacial spasm and vertigo, or tinnitus accordingly. Vessel loops in the cerebellopontine cisterns may cause compression at the root entry or exit zone of the cranial nerves V, VII, and VIII, a phenomenon which is called "vascular loop syndrome." Megadolichobasilar artery and aneurysms of the vertebrobasilar system can also lead to dislocation and compression of the cranial nerves and brain stem. Three-dimensional CISS MR imaging and MR angiography are useful in the detection of neurovascular compression. Microvascular decompression is an effective surgical procedure in the management of compression syndromes of the cranial nerves V, VII, and VIII.     

Vaskuläre Erkrankungen des Kleinhirnbrückenwinkels

Vascular anomalies of the cerebellopontine angle are rare compared to tumors in this area. Irritation of the trigeminal, facial, or vestibulocochlear nerve may cause trigeminal neuralgia, hemifacial spasm and vertigo, or tinnitus accordingly. Vessel loops in the cerebellopontine cisterns may cause compression at the root entry or exit zone of the cranial nerves V, VII, and VIII, a phenomenon which is called “vascular loop syndrome.” Megadolichobasilar artery and aneurysms of the vertebrobasilar system can also lead to dislocation and compression of the cranial nerves and brain stem. Three-dimensional CISS MR imaging and MR angiography are useful in the detection of neurovascular compression. Microvascular decompression is an effective surgical procedure in the management of compression syndromes of the cranial nerves V, VII, and VIII.     

听神经瘤CT、MRI诊断比较

目的：比较听神经瘤的CT、MRI诊断价值。方法：回顾性分析26例经手术和病理证实的听神经瘤的CT、MRI表现。结果：听神经瘤的MRI表现为桥小脑角区圆形或类圆形肿块,于T1WI呈低信号或等信号,T2WI呈高信号或混杂信号;增强扫描显示病灶实质部分及增粗的听神经明显强化,呈“苹果柄”样改变。CT表现为桥小脑角部低密度或等密度病灶,薄扫可见同侧内听道口扩大。结论：CT能直观地显示内听道口的扩大,但常规扫描易漏诊。／MRI多层面成像及无骨伪影的优点,对显示听神经瘤瘤体及病侧听神经增粗很有价值,增强后的“苹果柄”样改变是听神经瘤特征性的表现。     

桥小脑角区显微手术治疗三叉神经痛101例

目的　介绍１０１ 例三叉神经痛经桥小脑角显微手术治疗经验。方法　分析１０１ 例三叉神经痛的病因、术式选择及复发率，并就减少并发症进行探讨。结果　３ 例胆质瘤切除术后三叉神经痛症状均消失。余９８ 例术后疼痛即刻消失者８８ 例；１０ 例仍疼痛但程度减轻，均存在于６２ 例行微血管减压术式者中，其中５ 例于术后１０ ｄ 内疼痛消失，另５ 例口服药物可控制。近期有效率１００ ％ ，近期治愈率８９８ ％ 。无死亡病例。共随访成功６５ 例，随访时间０５ ～７ ａ ，复发６例。结论　治疗三叉神经痛的桥小脑角区显微是最接近其病因的治疗，并视术中情况进一步实施微血管减压术或感觉根部分切断术，是治疗三叉神经痛较理想的手术。     

Evaluation of MR cisternography of the cerebellopontine angle using a balanced fast-field-echo sequence: preliminary findings

We evaluated the feasibility of MR cisternography by the balanced fast-field-echo (bFFE) sequence, comparing with that by a turbo-spin-echo (TSE) sequence, for cerebellopontine angle lesions on a 1.5-T imager (Gyroscan Intera, Philips, Best, The Netherlands). The bFFE MR cisternograms depicted target cranial nerves with less cerebrospinal fluid pulsation artifacts than TSE cisternograms and visualized an acoustic schwannoma in 6 of 44 patients with suspicion and a causative vessel of hemifacial spasm in all of 3 patients in a short scanning time (1 min 53 s). The bFFE sequence can be promising for MR cisternography in the diagnosis of cerebellopontine angle lesions.     

Facial nerve neuromas: CT findings

Although neuromas of the facial nerve are rare, they present with uniform clinical and radiological findings. Their pluridirectional tomography findings have been well described; however, the appearance of the intracranial extension of the neuroma which is best visualized by CT has not been emphasized. We report five cases of facial nerve neuromas with particular attention to their intracranial extension. For comparative purposes we also have reviewed 10 cases of acoustic and eight cases of trigeminal neuromas, all involving the cerebellopontine angle (CPA) and the middle cranial fossa. Two of the five facial nerve neuromas affected the second and third segments of the facial canal, and three involved both the CPA and the middle cranial fossa spreading across the midpetrosal bone. This type of tumor extension seems to be characteristic of facial nerve neuromas. In acoustic and trigeminal neuromas the tumor crossing toward the middle fossa takes place via the tentorial hiatus (acoustic) and the petrous apex (trigeminal).