MRI of an unenhancing tuberculum sellae meningioma

We present a tuberculum sellae meningioma with intrasellar extension which did not enhance with intravenous gadolinium. Identification of the diaphragma sellae, possible only on the unenhanced short TR/TE sequence, was crucial for differentiating the lesion from a pituitary adenoma, and therefore for the correct surgical approach.     

Anatomic and histologic features of diaphragma sellae that effects the suprasellar extension

This study aimed to determine the anatomical and histological features of diaphragma sellae that affect the suprasellar extension of intrasellar tumours. Twenty-four fresh adult cadavers were dissected for the study. Diaphragma sellae and pituitary capsules with sellar structures were resected. The diaphragma sellae was anatomically reviewed in detail. Immunohistochemical staining was performed for collagen types I, II, III, and IV. We examined the suprasellar growth of 13 sellar tumours extending superiorly through the diaphragma sellae by performing a series of 2704 endoscopic transnasal operations to analyse the anatomic and histologic results of the study. The diameter of the foramen of diaphragma sellae varied between specimens. Of 24 specimens, the diaphragma sellae in five (21%) had a tight-type foramen and those in 19 (79%) were more spacious. An increased expression of collagen types I and IV was observed in the pituitary capsule and the diaphragma sellae. In this clinical series, we observed that all types of sellar tumours could expand through the foramen. We observed radiologically and intraoperatively that the diaphragma sellae was displaced laterally and formed a dome in two cases with an adenoma extending to the suprasellar area. Two types of suprasellar extension through the diaphragma sellae are possible: 1) The collagen structure of diaphragma sellae can be destroyed by invasive tumours; 2) The morphology of the foramen of the diaphragma sellae facilitates suprasellar tumoural extension. All sellar tumours, including non-invasive cystic tumours, may invade the suprasellar area by expanding through the foramen of the diaphragma sellae.     

巨型鞍结节脑膜瘤的显微外科治疗

目的 总结、分析巨型鞍结节脑膜瘤(MTSM)的病理解剖及血供特点,探讨其相应的显微外科治疗对策.方法 回顾分析1998至2010年应用显微神经外科技术、理念,针对MTSM独特的病理解剖、血供特点,采取颅底入路、术中控制性降压、利用"肿瘤通道"原位切除的16例巨型鞍结节脑膜瘤患者的临床资料,其中男5例,女11例,年龄26～65岁,平均48.5岁;随访14例,时间4～132个月,平均74.9个月.结果 肿瘤最大径51.1～76.2 mm,平均5 8.9 mm;Simpson Ⅰ、Ⅱ、Ⅲ及Ⅳ级切除分别为3、9、3及1例;术后死亡1例,视力不同程度好转10例,无变化2例,恶化2例,短暂尿崩9例.结论 深入研究MTSM独特的血供、病理解剖特点至关重要,针对性地采取相应的显微外科对策、利用"肿瘤通道"原位手术切除应为MTSM较为理想的治疗方案.

Abstract：

Objective To summarize the characteristics of the pathological anatomy and blood supply model of massive tuberculum sellae meningiomas (MTSM) and explore its corresponding microneurosurgical strategies. Methods The clinical data of 16 MTSM patients were reviewed retrospectively. From January 1998 to January 2010, according to their unique pathological anatomy and blood supply model, all patients underwent microneurosurgical removal with induced hypotension through tumor corridor by the bi-subfrontal anterior longitudinal fission ( n = 14), right frontolateral approach ( n =1 ) and pterional approach (n = 1 ). There were 5 males and 11 females with a mean age of 48. 5 years old ( range: 26 - 65 ). But the mean follow-up period was 74. 9 months ( range: 4 - 132) in 2/4 cases. Results Among all cases, the mean tumor diameter was 58.9 mm ( range: 51.1 - 76. 2 mm). Simpson grade Ⅰ, Ⅱ ,Ⅲ, Ⅳ removal of MTSMs were accomplished in 3, 9, 3 and 1 case respectively. One case died within 4postoperative days. Visual acuity improved in 10 patients, remained unchanged in 2 and deteriorated in 2.Transient postoperative diabetes insipidus occurred in 9 cases. Conclusion It is critical to understand the unique characteristics of pathological anatomy and blood supply model of MTSM so as to adopt proper microneurosurgical strategies to remove it in situ.     

Comparison of lateral and superior walls of the pituitary fossa with clinical emphasis on pituitary adenoma extension: cadaveric-anatomic study

Pituitary adenomas extend to the suprasellar region via diaphragmal passage and extend to the cavernous sinus via the medial wall (MW). Better understanding of the dynamics of suprasellar and parasellar extension of sellar region pathologies requires microanatomical comparison of diaphragma sellae (DS) and the MW of the cavernous sinus. This study provides the first detailed quantitative assessment between DS and MW of the cavernous sinus. Microanatomical details and histopathological examinations of the DS and MWs of the cavernous sinus were studied in sphenoid block samples obtained from adult cadavers, and the thicknesses of the DS and the MW of the cavernous sinus were measured. Mean thickness of the DS was 216.73 ± 51.26 μm in the center and 367.33 ± 133.66 μm in the periphery. Mean thickness of the lower third of the MW was 161.53 ± 53.86 μm and that of the upper third was 278.46 ± 162.79 μm. Difference between the thicknesses of the upper and lower thirds was significant (P < 0.001). When the central thickness of the DS and lower third of the MW were compared, a significant difference was found (P < 0.01). Our measurements suggest that when the DS is thick and the stalk opening is complete, the thickness of the lower third of the medial wall could be the major determinant of parasellar extension.     

Transsphenoidal-Transtuberculum Sellae Approach for Supradiaphragmatic Tumours: Technical Note

Summary  The Classic transsphenoidal approach may not afford sufficient exposure for a supradiaphragmatic tumour adjacent to the pituitary stalk. Various transcranial approaches have been utilized to access such a lesion with adequate results. This report describes a less invasive technique, termed “transsphenoidal-transtuberculum sellae approach”. This modified transsphenoidal approach requires a bone ablation of the tuberculum sellae, the limbus sphenoidalis, and a portion of the planum sphenoidale, in addition to an opening of the anterior floor of the sella turcica. The dura mater on the tuberculum sellae and the pituitary fossa is sectioned with a bilateral obliteration of the anterior intercavernous sinus. The anterior pituitary gland is not necessarily resected. The optic chiasm, optic nerves, pituitary stalk, and tuber cinereum can be directly observed, making it possible to safely dissect a lesion from these structures. Utilizing this approach, we have removed 14 supradiaphragmatic tumours without complications and dealt with other lesions such as optic nerve injuries or cerebrospinal fluid rhinorrhea, leaving pituitary function intact. The transsphenoidal-transtuberculum sellae approach for accessing small supradiaphragmatic tumours is a useful procedure requiring only a minor modification of the classic transsphenoidal technique.     

内镜垂体瘤切除术中鞍膈形态与肿瘤残余及并发症的关系

目的：探讨经鼻内镜垂体瘤切除术中鞍膈下降形态与肿瘤残余、尿崩症及术中脑脊液漏的关系。方法回顾分析2012年2月～2013年3月我科80例鼻内镜垂体瘤切除术的临床资料。术中肿瘤切除后鞍膈下降形态分为4型：A型：鞍膈以垂体柄为中心对称性降至鞍区;B型：鞍膈非对称性降至鞍区,垂体柄偏向一侧;C型：鞍膈对称性下降,垂体柄移至鞍背;D型：鞍膈未或仅有轻微下降,垂体柄位置模糊不清。结果 A、B、C、D四型鞍膈的肿瘤残余率、尿崩症发生率及脑脊液漏发生率有统计学差异（χ2＝11．069,P＝0．011;χ2＝11．483,P＝0．009;χ2＝8．890,P＝0．031）。肿瘤残余多见于B、D型鞍膈,肿瘤残余发生率与A、C型鞍膈有统计学差异（Z＝-2．409,P＝0．016;Z＝-2．062,P＝0．039;Z＝-2．477,P＝0．013;Z＝-2．245,P＝0．025）,但B型与D型肿瘤残余率无统计学差异（Z＝-0．791,P＝0．429）。尿崩症、术中脑脊液漏多见于A、C型鞍膈,发生率与B、D型鞍膈有统计学差异（P＜0．05）,但A型与C型尿崩症、脑脊液漏发生率无统计学差异（Z＝-0．195, P＝0.846;Z＝-0．362,P＝0．717）。结论鞍膈下降形态可以作为肿瘤残余、尿崩症及术中脑脊液漏的一个解剖参考。     

经前纵裂入路显微手术切除鞍结节脑膜瘤的疗效观察及安全性评估(附19例报告)

目的探讨经前纵裂入路显微手术切除鞍结节脑膜瘤(TSM)的临床疗效,并评估其安全性。方法回顾性分析2007年2月至2012年8月期间在南方医科大学附属小榄医院神经外科治疗的19例TSM患者采用经前纵裂入路显微手术切除的临床资料。结果 19例患者均成功完成手术,SimpsonⅠ级和Ⅱ级切除18例(94.7%),无死亡病例出现。术后对所有患者随访3²0个月,均未出现复发,3个月时14例患者的视力有不同程度好转,5例视力无好转,11例视野缺损较术前改善。术后出现尿崩症2例,额叶静脉性梗死1例,发热1例。结论经前纵裂入路显微手术切除TSM全切率高,预后良好,安全有效,可作为TSM优选的手术方式。     

鞍结节脑膜瘤的显微手术治疗

目的探讨鞍结节脑膜瘤的早期诊断,手术入路技巧。方法对苏大附一院39例鞍结节脑膜瘤的临床资科进行回顾性分析。结果肿瘤全切除28例、次全切除6例,部分切除5例,无手术死亡。结论CT或MR检查对鞍结节脑膜瘤早期确诊提供了帮助。根据肿瘤的大小及生长方向确定手术入路,显微手术是鞍结节脑膜瘤的最佳治疗方法。