原发性黑素细胞病变

原发性黑素细胞病变是一组起源于软脑膜黑素细胞的、呈弥漫性或局限性生长的良、恶性肿瘤，包括：①弥漫性黑素细胞增生症；②黑素细胞瘤；③恶性黑素瘤；④脑膜黑素瘤病。可出现交界性或混合性肿瘤。弥漫性黑素细胞增生症的CT和MRI表现为软脑膜的弥漫性增厚、强化。黑素细胞瘤内如含有较多的黑素，则表现为T1WI高信号、T2WI低信号，增强时肿瘤通常出现均匀强化表现。恶性黑素瘤也可表现为T1WI高信号、T2WI低信号．主要取决瘤体内黑素含量和是否伴有出血，增强时肿瘤通常也出现均匀强化表现。脑膜黑素瘤病可以表现为脑内外多发的T1WI高信号、T2WI低信号结节影，增强后可出现脑膜的弥漫性强化和(或)脑内的结节状强化。原发性黑素细胞病变的上述这些影像学表现都是非特异性的。     

Percutaneous Biopsy of Musculoskeletal Lesions

Percutaneous biopsy is a minimally invasive technique that yields a high diagnostic accuracy at a relatively low cost in musculoskeletal lesions, especially tumors and infection. In this article, technical refinements improving the results of percutaneous biopsy of musculoskeletal lesions are reviewed, especially the type of radiological guidance, the different biopsy needles available, and the technique of approach depending on the lesion site. Reported complications, results, and indications of musculoskeletal percutaneous biopsy are also discussed.     

Radiosurgery of Small Skull-Base Lesions

BACKGROUND AND PURPOSE: Intensity-modulated stereotactic radiotherapy (IMSRT) has shown the ability to conform the dose to concavities and to better avoid critical organs for large tumors. Given the availability of an electronically driven micro-multileaf collimator, both intensity-modulated stereotactic radiosurgery (IMSRS) and dynamic conformal arc (DCA) technique (DCA) can be performed at the Novalis Shaped Beam Surgery Center, University of Erlangen-Nuremberg, Germany, since 12/2002. This study evaluates both techniques in small skull-base tumors treated with radiosurgery. MATERIAL AND METHODS: Between 12/2002 and 04/2004, a total of 109 radiosurgical procedures were performed in 77 patients, equally distributed between patients with acoustic neuroma (AN), pituitary adenoma (PA) and meningeoma (M). Six index patients (n = 2 AN, n = 1 PA, n = 3 M) routinely planned for dynamic arc stereotactic radiosurgery were replanned using the IMSRS approach (BrainScan, BrainLAB, Heimstetten, Germany). The RTOG radiosurgery quality assurance guidelines, isodose volumes, doses to organs at risk (OAR), and dose delivery criteria were compared. RESULTS: DCA was superior to IMSRS for homogeneity and coverage. IMSRS could keep the high-dose-irradiated volumes (90% isodose volume) lower than DCA in the PA and AN with very small volumes, but all other lower dose volumes were larger for IMSRS. Dose maxima to OAR were higher for IMSRS. Treatment delivery time for IMSRS would clearly exceed treatment time for DCA by a factor of 2-3. The integral absorbed dose to the brain was much higher in the IMSRS than in the DCA approach (factor 2-3). CONCLUSION: RTOG radiosurgery guidelines were best met by the DCA rather than IMSRS approach for the treatment of small skull-base lesions. The IMSRS approach will increase the time for planning, dose delivery and integral dose to the brain. Thus, IMSRT techniques are recommended for fractionated stereotactic radiotherapy to larger volumes rather than for radiosurgery in small skull-base lesions.     

腹膜腔囊性病变的CT表现

目的：探讨腹膜腔囊性病变的CT诊断及应用价值。方法：对照分析57例腹膜腔囊性病变的CT表现和手术、病理结果。结果：21例腹膜腔囊肿或囊腺瘤、囊腺癌CT均表现为边界清晰的囊性或囊实性包块,7例肠系膜囊肿发现囊肿与肠系膜根部相连。5例腹膜腔假性黏液瘤则在肝脏前、后间隙和结肠下间隙见多个有分隔状囊性肿块。3例腹膜腔囊性间皮瘤局限于下腹腔,壁稍厚,有强化。4例腹膜腔淋巴管瘤位于胃脾肾间隙和胃肝间隙,5例腹膜腔血肿均有外伤史,表现为上腹部器管间隙内边缘清晰的囊性包块。12例腹膜腔脓肿均有腹部手术和术后发热史。结论：CT能清晰地显示腹膜腔囊性病变的部位、形态和范围,对临床诊断和治疗有重要价值。     

甲状旁腺功能亢进的定位诊断

比较了８５例临床诊断为甲状旁腺功能亢进的患者使用（２０１）Ｔｌ／（９９ｍ）Ｔｃ双核素减影技术、（９９ｍ）Ｔｃ－ＭＩＢＩ和Ｂ型超声做病灶术前定位的结果。术中共发现９９个病灶，双核素显像检出４９个病灶，Ｂ超发现６７个病灶，灵敏度分别为５０％和６７％。其中８例患者用（９９ｍ）Ｔｃ－ＭＩＢＩ检查的灵敏度为６７％（６／９）；对异位甲状旁腺病灶核素显像的灵敏度为８４．６％（１４／１７），Ｂ超为４１％（７／１７）。     

软组织病变的MRI诊断

目的：评价ＭＲＩ对软组织病变（包括肿瘤和非肿瘤性病变诊断作用）。方法：研究了７９个病人的９５个（良性４９个，恶性４６个）软组织病变的影像特点，将ＭＲ表现与最终诊断（病理结果ｎ＝７５和临床综合诊断ｎ＝２０）做比较。从（１）ＭＲ对病变的显示；（２）定位诊断；（３）定性诊断及（４）造影剂增强对显示病变的作用等方面进行分析。结果：在综合分析Ｔ１ＷＩ和Ｔ２ＷＩ图像的基础上，ＭＲＩ对各种软组织病变的检出率为１００％。ＭＲ对病变的位置、边界、病变侵犯骨和神经血管的显示与手术结果对照符合率达１００％，显示病变大小为８１．３％。９５个病变定性诊断的正确率达７３．７％，而对其中１９例脂肪瘤、海绵状血管瘤和囊肿等病变，ＭＲ不仅诊断正确率高（９４．７％），而且可以做出组织学诊断。静脉增强后（１２／１３）９２．３％的病变可以提供更多的诊断信息。结论：ＭＲ对软组织病变是一很好的诊断方法。     

CT引导下寰枢椎病变经皮穿刺活检

目的 全面系统地探讨寰枢椎病变CT引导下穿刺活检的入路选择,评价其安全性及临床应用价值。材料与方法 25例寰枢椎病变行CT引导下经皮穿刺活检。穿刺部位包括C1及C2椎体的各个部位。根据病变的部位不同,设计相应的进针路径,穿刺取材。结果 25例中,24例获得明确病理诊断,穿刺活检准确率96％。其中12例手术治疗,穿刺病理与手术病理符合率100％。无并发症发生。结论 寰枢椎病变解剖关系复杂,毗邻脊髓及重要的大血管,选择适宜的穿刺路径尤为关键。寰枢椎病变不同的穿刺路径,只要避开大血管及脊髓,操作是比较安全的。为临床确定治疗方案提供了必要的病理依据。     

骶髂关节病变的CT诊断

目的 阐明骶髂关节病变的ＣＴ表现。材料与方法 搜集经临床确诊或病理证实的35例骶髂关节病变者,男22例,女13例。其中强直性脊柱炎（AS）13例,类风湿性关节炎（RA）7例,化脓性骶髂关节炎2例,骶髂关节结核5例,髂骨致密性骨炎6例,创伤性关节炎2例,结果 CT表现：AS常双侧对称发病,自关节下部开始,关节面硬化与破坏,间隙狭窄或消失,骨桥形成,RA常一侧发病,易侵犯关节上壮举剖,关节面密度减低,骨质疏松,关节面下出现周围硬化的小囊状骨缺损;化脓性骶髂关节炎常单发,骨一侧发病,易侵犯关节上半部,关节面密度减低,骨质疏松,关节面下出现周围硬化的小囊状骨缺损;化脓性骶髂关节炎常单发,骨质疏松,破坏,半生,关节间隙增宽或变窄,关节囊肿胀,关节强直,周围软组织肿胀或钙化;骶髂关节结核常单侧发病,多位于关节中下部,关节面模糊,骨质破坏及死骨形成,关节间隙增宽,常伴冷脓肿和窦道形成;髂骨致密性骨炎示髂骨面硬化区,不累及关节;创伤性关节炎骨关节面增生,浓密,关节间隙狭窄,可伴骨性强直。结论 骶髂关节病变的CT表现各不相同,CT能清楚显示骶髂关节及其周围结构,是目前诊断骶髂关节病变最理想的检查手段。     

CT-Guided Percutaneous Biopsy of Intrathoracic Lesions

Percutaneous CT-guided needle biopsy of mediastinal and pulmonary lesions is a minimally invasive approach for obtaining tissue for histopathological examination. Although it is a widely accepted procedure with relatively few complications, precise planning and detailed knowledge of various aspects of the biopsy procedure is mandatory to avert complications. In this pictorial review, we reviewed important anatomical approaches, technical aspects of the procedure, and its associated complications.     

涎腺良恶性病变的CT鉴别诊断

目的探讨CT对涎腺良恶性病变鉴别诊断的价值。方法回顾性分析经手术病理证实(个别经穿刺细胞学证实)的涎腺良恶性病变36例,其中良性肿瘤19例,慢性炎症5例,结核1例,恶性肿瘤11例,从形态、密度、边缘、皮肤是否受累及颈淋巴结有无肿大等方面分析其CT表现。结果良性肿瘤大多形态规则(17/19),边缘清晰锐利(16/19),与周围组织分界清楚,慢性炎症轮廓较规则,但边缘模糊,增强扫描强化程度不一。恶性肿瘤CT多表现为形态不规则(7/11),边缘模糊,与周围组织分界不清,相邻的脂肪间隙模糊、消失,皮下脂肪层受侵,表皮线样影消失。部分病例(3/11)表现为涎腺弥漫性增大而形成“铸型”。大多数良性病变和恶性肿瘤的密度均表现为密度不均匀甚至是大范围的囊变、坏死。结论CT对涎腺良恶性病变的鉴别诊断具有很高的价值。