儿童正常垂体腺的MR研究

目的：通过ＭＲＩ研究儿童正常垂体腺形态、大小及信号强度。材料和方法：５２例非垂体腺疾病的颅脑ＭＢ资料。年龄３～１５岁。观察测量矢状面Ｔ１加权图像上垂体腺的形态、高径、垂体柄宽径及后叶信号特征。结果：儿童正常垂体腺形态分：平坦型２７例（５１．９％），凹陷型１５例（２８．８％），隆凸型１０例（１９．３％）。垂体腺高径：３～５岁３．９±０．３ｍｍ，５．１～１０岁４．２±０．５ｍｍ，１０．１～１５岁５．３±０．４ｍｍ。垂体柄宽径１．４±０．５ｍｍ。垂体后叶均呈高信号（１００％）。结论：１．儿童垂体腺形态以平坦型最常见。２．垂体腺高径与年龄呈正线性关系。３．垂体柄未见中断。     

腺癌性孤立性肺结节的^18F—FDG PET／CT表现

目的探讨腺癌性孤立性肺结节（ASPN）的^18F—FDG PET／CT显像特点。方法回顾分析35例ASPN的^18F-FDG PET／CT显像形态学和代谢特点,计算SUVmax,以公式[（延迟显像SUVmax-早期显像SUVmax）／早期SUVmax×100％]计算△SUVmax。以SPSS11．5软件对数据分别行t检验、方差分析和Fisher确切概率法检验。结果（1）42．86％（15／35）ASPN呈典型的癌性肺结节表现（结节状FDG摄取增高）,另有57．14％（20／35）ASPN FDG摄取呈片状、云雾状、肉眼无法辨认;结节状、云雾状、片状、肉眼无法辨认ASPN的SUVmax大小顺序递减,不同FDG摄取形态的ASPN早期和晚期SUVmax差异均有统计学意义,F=30．696和24．758,P均〈0．001。（2）54．29％（19／35）ASPN SUVmax≥2．5,45．71％（16／35）ASPN SUVmax〈2．5。（3）68．57％（24／35）ASPN呈实性密度结节,31．43％（11／35）ASPN呈“磨玻璃”密度结节;早期SUVmax分别为4．54±2．69、1．30±0．87,t=-5．234,P〈0．001。（4）延迟显像ASPN的SUVmax为422±3．52,高于早期显像的3．49±2．72（t=-4021,P〈0．1301）;延迟显像SUVmax是否增高与早期显像SUVmax的高低相关：94．74％（18／19）SUVmax≥2．5ASPN的△SUVmax为正值,仅56．25％（9／16）SUVmax〈2．5ASPN的△SUVmax为正值,P=0．013。（5）高分化ASPN SUVmax为1．70±1．51,低于中低分化ASPN的4．91±2．69,t=-3．951,P〈0．001,且△SUVmax〉0的比例（10／17）也低于中低分化ASPN（13／14）,P=0．045。结论ASPNFDG摄取形态、代谢活性差异大,SUVmax〈2．5ASPN比例较高,△SUVmax对这类结节良恶性的鉴别有一定帮助。     

甲状腺乳头状癌CT表现

目的：通过和甲状腺腺瘤比较，分析甲状腺乳头状癌的CT特征。材料和方法：回顾性分析经病理证实的18例甲状腺乳头状癌的术前CT表现，并以同期病理证实的23例甲状腺腺瘤作对照，全部病例CT扫描均包括平扫和增强扫描。统计采用卡方检验。结果：甲状腺乳头状癌的病灶77．78％（14／18）为单侧，其余3例为双侧、1例位于峡部；甲状腺腺瘤的病灶91．30％（21／23）为单侧，其余2例为双侧。甲状腺乳头状癌CT表现不同于腺瘤：病变密度不均匀达77．78％（14／18），明显多于腺瘤的39．13％（9／23，P=0．031）；微钙化50％（9／18），多于腺瘤的8．7％（2／23，P=0．009）；形态不规则有66．7％（12／18），明显高于腺瘤的13．04％（3／23，P=0．001），边缘不清有66．7％（12／18），明显高于腺瘤的21．74％（5／23，P=0．004）。乳头状癌中12例增强后明显强化，但与腺瘤无统计学差异，另有6例有周围结构侵犯、3例伴有颈部淋巴结转移。结论：和甲状腺腺瘤相比，甲状腺乳头状癌的CT表现以密度不均匀、边缘不清楚、形态不规则和微钙化为特征，周围组织结构侵犯和颈部淋巴结转移均相对少见。     

^18F-FDGPET／CT影像特征对甲状腺结节的诊断效能

目的研究甲状腺结节^18F-FDGPET／CT影像特征对甲状腺结节良恶性的鉴别诊断效能。方法回顾性研究68例[男24例,女44例,平均年龄（52．8±10．58）岁]2006年1月至2012年12月间经PET／CT检查发现甲状腺结节且有术后病理结果的患者,分析其PET／CT图像特征并获得特征参数,包括结节边界清晰度、密度均匀性、钙化情况、包膜情况、平均CT值、结节大小及SUVmax。以术后病理结果为“金标准”,采用Mann-Whitney u检验、x^2检验及ROC曲线对各参数的诊断效能进行统计分析。结果68例患者中,病理结果显示恶性18例,良性50例。结节密度是否均匀、有无钙化灶、有无包膜对于甲状腺结节良恶性鉴别均无统计学意义（x^2=0．21、0．01、0．43,均P〉0．05）,结节平均CT值及结节大小亦无鉴别意义（均AUC〈0．5）。结节边界是否清晰对良恶性结节鉴别有统计学意义（x^2=8．06,P〈0．05）,其诊断灵敏度、特异性及准确性分别为55．6％（10／18）、80．0％（40／50）和73．5％（50／68）。良性结节SUVmax为3．16±1．84,恶性结节SUVmax为8．53±7．09,差异有统计学意义（u=-4．281,P〈0．01）。以SUVmax为评价指标,其ROC的AUC为0．841（95％CI：0．726—0．955）,最大约登指数（0．562）对应SUVmax为4．25,其诊断灵敏度、特异性及准确性分别为72．2％（13／18）、84．0％（42／50）和80．9％（55／68）。结论可依据^18F—FDGPET／CTSUVmax对甲状腺结节良恶性进行判断,但同机CT影像特征价值有限。     

正常垂体腺形态MRI的研究

目的 研究国人正常垂体腺形态。材料与方法 采用1．5T超导磁共振成像系统,于MRI T1WI上,标准正中矢状位观察2557例正常人垂体腺形态。结果 平坦型,男性约为61％－72％,女性约为50％－84％;凹陷型,男性约为4％－32％,女性约为3％－46％;隆凸型,男性约为6％－35％,女性约为4％－46％。在30－40岁、50－60岁、60岁以上年龄段中,男女在形态上有显著差异。结论 垂体腺的形态与年龄、性别有一定的关系。平坦型较为稳定,凹陷型随年龄增加而增加,隆凸型随年龄增加而减少。     

ROC曲线评价18F—FDGPET／CT、99Tcm—MDP骨显像及二者联合对骨转移的检出效能

目的采用ROC曲线比较18F-FDGPET／CT、99TcmMDP骨显像及二者联合对骨转移患者的检出效能。方法296例恶性肿瘤患者在2个月内同时接受了18F-FDGPET／CT和99TcmMDP骨显像,对2种显像结果按5分法（0分：骨转移阴性,1分：可能阴性,2分：不能确定,3分：可能阳性,4分：肯定阳性）分别评分,两者之和为联合评分值。以病理诊断或临床随访为确诊“金标准”,采用。检验比较ROC曲线下面积,以评价骨显像、PET／CT及联合评分法对骨转移患者的检出效能,采用r检验比较不同方法在各自最佳诊断阈值下的灵敏度、特异性、准确性、阳性预测值、阴性预测值。结果296例患者中,确诊骨转移阳性61例（占20．6％）、阴性235例（占79．4％）。骨显像、PET／CT及联合评分诊断骨转移的ROC曲线下面积（95％可信区间）分别为0．919（0．867—0．971）、0．949（0．906～0．991）、0．994（0．988～0．999）,联合评分法的曲线下面积明显大于骨显像（z=2．866,P=0．004）和PET／CT（z=2．027,P=0．043）各自单独评分法,骨显像和PET／CT法曲线下面积差异没有统计学意义（z=0．881,P=0．378）。最佳阈值点下,骨显像和PET／CT单独检出骨转移患者的灵敏度、特异性、准确性、阳性预测值、阴性预测值分别为90．2％（55／61）、85．1％（200／235）、86．1％（255／296）、61．1％（55／90）、97．1％（200／206）和88．5％（54／61）、97．0％（228／235）、95．3％（282／296）、88．5％（54／61）、97．0％（228／235）,而联合评分检出的结果分别为98．4％（60／61）、95．7％（225／235）、96．3％（285／296）、85．7％（60／70）、99．6％（225／226）。PET／CT对骨转移患者检出的特异性（X2=19．600,P〈0．001）、准确性（X2=13．755,P〈0．001）、阳性预测值（x2=13．608,P〈0．001）均高于骨显像,灵敏度（r=0,P=1．000）差异无统计学意义;与骨显像、PET／CT单独评分比较,联合评分法检出的特异性（X2=19．862,P〈0．001）、准确性（x2=23．361,P〈0．001）和阳性预测值（x2=11．791,P=0．001）均明显高于骨显像,灵敏度明显高于PET／CT（x2=4．167,P=0．031）。结论18F—FDGPET／CT对骨转移患者的检出效能优于99Tcm—MDP骨显像,二者联合明显提高了对骨转移患者的检出率。     

PET／CT对肺部肿块的诊断

目的探讨^18F-脱氧葡萄糖（FDG）PET／CT显像对肺部肿块的诊断和鉴别诊断价值,研究肿块大小和PET／CT显像最大标准摄取值（SUVmax）的相关性。方法对经病理检查和综合手段（临床、影像学或血液学等检查）证实的85例肺部肿块（59例恶性肿瘤、26例肺部良性肿块）患者进行回顾性分析。分别观察肺部肿块的CT形态（是否有脐凹、分叶、短细毛刺、粗盐样钙化、表面粗糙等）及PET显像肺部肿块感兴趣区（ROI）的FDG SUVmax。结合临床和病理诊断结果,分别比较分析PET、CT、PET／CT对肺部肿块诊断的灵敏度、特异性、准确性。对肿块大小和SUVmax进行Pearson相关分析。结果PET对85例肺部肿块患者诊断的灵敏度、特异性和准确性分别为89．8％（53／59）、61．5％（16／26）、81．2％（69／85）;CT分别为88．1％（52／59）、65．4％（17／26）、81．2％（69／85）;PET／CT分别为96．6％（57／59）、80．8％（21／26）、91．8％（78／85）。59例恶性肿瘤的肿块大小和SUVmax明显相关（r=0．617,P〈0．001）,而26例肺部良性肿块大小和SUVmax不相关（r=0．211,P〉0．05）。结论”F-FDG PET／CT对肺部肿块较单纯PET、单纯CT的诊断灵敏度、特异性、准确性高;恶性肿瘤的肿块大小和SUVmax正相关,而良性病变的大小和SUVmax不相关。     

核素显像心肌灌注缺损与CTCA冠状动脉不同狭窄程度的关系分析

目的通过分析核素显像心肌灌注缺损与CTCA示冠状动脉（简称冠脉）不同狭窄程度间的关系,探讨和评价CTCA预测心肌灌注缺损的诊断效能。方法回顾性分析同期行CTCA和MPI患者478例。按目测法将CTCA所示冠脉管腔狭窄程度分成无狭窄、轻度狭窄、中度狭窄、重度狭窄和管腔闭塞,将MPI结果分成灌注正常和灌注缺损,分别在病例和血管水平统计各组灌注缺损的发生率。以MPI为参考标准,将CTCA预测心肌灌注缺损的冠脉狭窄程度判定界值设为≥50％或≥75％,在病例水平和血管水平上确定该方法的诊断效能。计数资料统计分析采用χ^2检验、χ^2分割法和Fisher确切概率法。结果478例患者中58例出现MPI灌注缺损。无论按病例水平还是血管水平分析,各组灌注缺损发生率有随冠脉狭窄程度增加而升高趋势（χ^2=116．62和483．83,P均〈0．05）。在病例水平上分析,当判定界值为≥50％或≥75％时,CTCA预测心肌灌注缺损的诊断灵敏度、特异性、阳性预测值、阴性预测值、准确性分别为62．1％（36／58）或34．5％（20／58）（χ^2=8．84,P〈0．05）、84．5％（355／420）或97．1％（408／420）（χ^2=40．16,P〈0．05）、35．6％（36／101）或62．5％（20／32）（χ^2=7．19,P〈0．05）、94．2％（355／377）或91．5％（408／446）（χ^2=2．18,P〉0．05）、81．8％（391／478）或89．5％（428／478）（χ^2=11．66,P〈0．05）;在血管水平上分析,判定界值为≥50％或≥75％时,CTCA预测心肌灌注缺损的诊断灵敏度、特异性、阳性预测值、阴性预测值、准确性分别为58．8％（40／68）或30．9％（21／68）（χ^2=10．73,P〈0．05）、95．9％（1768／1844）或99．0％（1826／1844）（χ^2=36．72,P〈0．05）、34．5％（40／116）或53．8％（21／39）（χ^2=4．59,P〈0．05）、98．4％（1768／1796）或97．5％（1826／1873）（χ^2=4．14,P〈0．05）、94．6％（1808／1912）或96．6％（1847／1912）（χ^2=10．31,P〈0．05）。结论心肌灌注缺损的发生率随冠脉狭窄程度增加有升高趋势。CTCA预测心肌灌注缺损的诊断特异性和阴性预测值较佳。当判定界值为≥75％时,其阳性预测值较判定界值为≥50％时有明显提高。     

手术复位治疗髋臼骨折移位259例

目的探讨髋臼骨折手术复位技巧，提高手术复位率。方法总结1995年9月-2005年10月259例手术治疗髋臼骨折的经验，并分析其临床疗效。结果解剖复位（移位≤1mm）203例，占78．4％。简单型髋臼骨折解剖复位率为96．0％（120／125）；复杂型髋臼骨折解剖复位率为61．9％（83／134），其中双人路解剖复位率为77．8％（42／54），单人路为51．3％（41／80）。满意复位（移位2～3mm）42例，占16．2％，其中简单型髋臼骨折5例，复杂型髋臼骨折37例；不满意复位（移位≥3mm）14例，占5．4％，均为复杂型髋臼骨折。187例获远期随访，随访时间8个月～6年6个月，平均2年5个月。按改良的Postel—D’Aubignel临床结果评分标准：优98例（占52．4％），良40例（21．4％），一般34例（18．2％），差15例（8．0％），优良率为73．8％。非解剖复位组优良率为38．9％（14／36）；解剖复位组优良率为82．1％（124／151），差异有统计学意义（x^2=28．1，P〈0．01）。结论提高复位技术、正确处理各个治疗环节，才能在有限的切口内提高位置深在、周围解剖关系复杂的髋臼骨折手术复位率。     

淋巴显像评估妇科肿瘤治疗后下肢淋巴系统损伤

目的分析妇科肿瘤治疗后淋巴水肿患者淋巴显像的影像特点,建立评估下肢淋巴系统损伤的方法。方法166例连续陛病例（332个肢体）双足第1,2趾间皮下注射99Tcm-DX111—185MBq（0．1～0．15m1）后行淋巴显像。根据显像结果,以淋巴管完整程度和淋巴皮下返流状况为指标,将下肢淋巴系统损伤分为0,1,2和3级。根据国际淋巴学会淋巴水肿临床分期标准,将淋巴水肿分为0,I,Ⅱa,Ⅱb和Ⅲ期。列联表,检验比较2种分类方法间的相关关系。矿检验分析淋巴系统损伤分级的临床特征。结果妇科肿瘤治疗后患者淋巴显像表现包括：下肢、盆腔和腹腔区域的淋巴管中断、皮下淋巴返流、淋巴管和淋巴结不显影、淋巴囊肿和淋巴瘘等。332个肢体,水肿分期为0,I,Ⅱa,Ⅱb和Ⅲ期的分别为65（19．6％）,71（21．4％）,131（39．5％）,62（18．7％）和3（0．9％）个,淋巴显像损伤分级为0,1,2和3级的数量分别为36（10．8％）,79（23．8％）,116（34．9％）和101（30．4％）个。统计学分析表明,2者间有良好的相关性（x2=313．483,P〈0．001）。临床分析表明,2和3级损伤所占比例放疗组高于非放疗组,分别为70．5％（158／224）和54．6％（59／108）,x2=9．662,P=0．022;有丹毒病史者3级损伤比例也高于无丹毒者,分别为73．1％（38／52）和43．9％（50／144）,x2=12．238,P〈0．001。随着淋巴水肿病程进展,3级损伤肢体数所占百分比逐渐增高、病程〈1．5年者为36．6％（34／93）,病程1．5～5年者为72．3％（34／47）,病程〉5年者为76．9％（20／26）（x2=23．123,P〈0．001）。不同类型妇科肿瘤（x2=4．000,P=0．676）、是否化疗（x2=0．411,P=0．938）对淋巴系统损伤分级无明显影响。结论淋巴显像损伤分级方法有助于评估妇科肿瘤治疗后患者的淋巴系统损伤程度,可为治疗后淋巴水肿的临床诊断和预防提供客观依据。     

CT appearance of the adolescent and preadolescent pituitary gland

Coronal computed tomographic scans of the pituitary gland in 27 normal children, adolescents, and young adults (ages, 8-21 years) and in a comparison group of adults (ages, 24-91 years) were evaluated retrospectively to test the applicability of published criteria for size and configuration of normal adult pituitary glands to younger patients. Statistically significant differences were found between the two groups, indicating that the pituitary gland in adolescents, particularly girls, is larger than in younger or older patients. The authors suggest that pubertal pituitary hyperplasia accounts for these findings. They conclude that standards for normal pituitary glands are probably inappropriate for adolescents.     

Thin section CT of normal pituitary glands

In order to better understand the CT appearance of the normal pituitary gland, we scrutinized the pituitary glands of 55 patients who had no clinical indication of pituitary abnormality. The superior surface of the pituitary gland was convex in 9 cases (16.4%), flat in 16 (29.1%), and concave in 30 (54.5%). All but one of the glands with upward convexity belonged to patients less than 40 years old. The height of the pituitary glands was from 2 mm to 7 mm in 48 (87.3%) and 7 mm to 9.1 mm in 7 (12.7%); all but one case was less than 40 years old. Although earlier reports have suggested the presence of a pituitary microadenoma when the gland has a convexity of its superior surface or is more than 7 mm in height, these findings can be seen in normal pituitary glands, particularly in younger individuals. Therefore, pituitary microadenoma should be diagnosed carefully in younger patients. The low density area frequently seen in the superior aspect of pituitary glands on axial scans was found to result from the concave superior surface of the gland. The pituitary stalk was off the midline in five patients (9%). Shifting of the pituitary stalk can be seen in the normal pituitary gland and is not always characteristic of microadenoma.     

Normal pituitary gland: changes in shape, size, and signal intensity during the 1st year of life at MR imaging

Magnetic resonance images of the pituitary glands in 48 endocrinologically normal neonates and infants were analyzed to determine the changes in pituitary gland size, shape, and signal intensity that occur during the 1st year of life. A progressive increase in the length--but not height--of the gland was seen throughout the 1st year. When corrections for total brain size were made, the pituitary gland was found to diminish in relative cross-sectional area throughout infancy. Upward convexity of the gland was seen in 63% of neonates less than 1 month of age, but in only 4% of infants older than 2 months. Hyperintensity of the adenohypophysis relative to the brain stem was visualized on T1-weighted images in 18 of the 24 (75%) neonates and infants less than 2 months old; this appearance was never seen in older infants. An area of high signal intensity was visualized in the posterior pituitary in 32 of 48 cases (67%), and its visualization was unrelated to age. The neonatal and young infant pituitary gland is thus significantly rounder, brighter, and relatively larger during the first 2 months of life than in later infancy.     

中国汉族正常成人垂体的高分辨率MRI研究

目的 研究中国汉族正常成人垂体MRI形态学特征,为建立国人正常标准脑提供垂体形态学数据.方法 采用全国多中心临床研究形式,选取18～70岁978名健康志愿者,并按18～30、31～40、41～50、51～60、61～70岁5个年龄段分为A、B、C、D、E组,行3D磁化强度预备梯度回波序列T1WI,利用3D后处理软件进行MPR,测量垂体体积及各方向径线,以及垂体柄与大脑中线、视交叉及垂体表面夹角.相同性别不同年龄分组的垂体测量值比较采用方差分析,相同组别不同性别垂体测量值的比较采用独立样本t检验分析,垂体分型数据采用x2分析.结果 (1)垂体体积:男性5组垂体体积分别为(1142±290)、(996±223)、(979±178)、(971±174)、(930±189)mm3,女性分别为(1247±210)、(1199±216)、(1108±196)、(1059±212)、(984±177)mm3,在不同年龄组间差异有统计学意义(F值分别为13.811、27.091,P值均<0.01),在男性30岁以后,女性40岁以后垂体体积变小;同年龄组女性垂体体积大于男性(P<0.05);垂体体积与性别、年龄、分型、正中高径、前后径和宽径相关(r=0.646,P<0.01).(2)垂体径线测量统计:垂体正中高径男性各组分别为(6.6±1.5)、(6.0±1.4)、(5.6±1.1)、(5.0±1.2)、(4.9±1.4)mm,女性分别为(7.9±1.6)、(6.4±2.0)、(5.6±1.7)、(5.1±1.7)、(4.4±1.4)姗,不同年龄组间差异有统计学意义(F值分别为24.582、62.978,P值均<0.01),30岁之前女性正中矢状高径大于男性,30岁之后男女垂体正中矢状高径逐渐减小,男性50岁后,女性60岁后降至最低;垂体正中矢状高径与性别、年龄相关(r=0.570,P<0.01).垂体宽径男性各组分别为(14.8±1.8)、(14.7±1.4)、(14.2±1.9)、(14.3±2.1)、(13.8±2.4)mm,女性各组分别为(14.9±1.8)、(15.8±1.7)、(15.5±2.1)、(15.6±2.2)、(14.9±2.1)mm,不同年龄组间差异有统计学意义(F值分别为4.566、4.233,P值均<0.05);垂体宽径与性别、体重、年龄相关(r=0.300,P<0.01).垂体前后径男性各组分别为(11.2±1.2)、(11.8±1.3)、(11.8±1.5)、(12.3±1.8)、(12.2±2.0)mm,女性分别为(11.9±1.3)、(12.5±1.5)、(12.4±1.5)、(12.9±1.6)、(12.7±1.6)mm,不同年龄组间差异有统计学意义(F值分别为7.270、5.903,P值均<0.01),60岁之前男性垂体前后径小于女性(P<0.05),且随后逐渐减小,女性前后径随年龄逐渐减小;垂体正中矢状前后径与性别、年龄相关(r=0.276,P<0.01).(3)垂体柄夹角统计:冠状面重组上垂体柄与垂体表面、视交叉及脑中线之间并无明显偏移,且男女之间差异无统计学意义(P>0.05).(4)垂体分型统计:不同性别年龄组间分型差异有统计学意义(x2值分别为44.212、107.518,P值均<0.01).随年龄增加,隆起型逐渐减少,凹陷型逐渐增加.结论 3D高分辨率MRI能够清晰显示垂体形态,结合3D后处理软件能够准确测量垂体体积及各方向径线以及垂体柄的夹角,为建立标准脑提供科学数据.     

MR imaging of the pituitary gland in infants and children: changes in size, shape, and MR signal with growth and development.

It has been reported that on MR images of the brain in neonates the entire pituitary gland is hyperintense. This is quite different from the well-established observation that portion is isointense. To better understand the development of the neonatal pituitary gland, we studied the timing and magnitude of changes in the size, shape, and MR signal of the pituitary gland in early childhood and infancy. The study included 76 infants and children ages 3 days to 4 years old. In each MR study, the signal intensity of the pituitary gland on T1-weighted coronal (n = 24) and sagittal (n = 76) images was compared with the signal intensity of the pons by using region-of-interest methods. The size and shape of the pituitary glands were recorded. Statistical comparisons were made for signal intensity and size of the pituitary gland between boys and girls and among age groups. The results showed that the MR signal of the posterior lobe remained hyperintense relative to the pons for all age groups represented in our study (through 4 years). However, the signal intensity of the anterior lobe gradually diminished and by approximately age 2 months was isointense with the pons. Thus, by approximately age 2 months the MR signal intensity of the infant's pituitary gland has changed from being entirely hyperintense (as seen in neonates) to isointense in the anterior lobe and hyperintense in the posterior lobe (as seen in adults). In the first 2 months of life the pituitary gland is bulbous in shape; later it has a flatter upper surface. We found no significant changes in the length or signal intensity of the pituitary gland; no differences among sexes in size, shape, or signal intensity were demonstrated. Findings of a bulbous pituitary gland and high MR signal of the entire pituitary are normal in neonates up to 2 months of age. After that, the gland gradually flattens and the MR signal of the anterior lobe decreases until it has characteristics similar to the adult pituitary. Lack of high signal or discovery of a small pituitary gland in a neonate should alert the radiologist to the possibility of pituitary malformation or dysfunction.     

Size, shape, and appearance of the normal female pituitary gland

One hundred seven women 18-65 years old were studied who were referred for suspected central nervous system disease not related to the pituitary gland or hypothalamus. High-resolution, direct, coronal, contrast-enhanced computed tomography (CT) was used to examine the size, shape, and density of the normal pituitary gland. There were three major conclusions: (1) the height of the normal gland can be as much as 9 mm; (2) the superior margin of the gland may bulge in normal patients; and (3) both large size and convex contour appear to be associated with younger age. It was also found that serum prolactin levels do not appear to correlate with the CT appearances. Both low- and high-density areas were seen within the gland, and may be due to either tumors, cysts, infarcts, or metastases. Noise artifacts inherent in high-detail, thin-section, soft-tissue scanning may be a limiting factor in defining reproducible patterns in different parts of the normal pituitary gland.     

High resolution computed tomography of the post partum pituitary gland

Summary Eight volunteer post partum female patients were examined with high resolution computed tomography during the week immediately after delivery. All patients received high dose (40–70 gm) intravenous iodine contrast administration. The scans were examined for pituitary gland height, shape and homogeneity. All of the patients had enlarged glands by the traditional standards (i.e. gland height of 8 mm or greater). The diaphragma sellae in every case bulged upward with a convex domed appearance. The glands were generally inhomogeneous. One gland had a 4 mm focal well defined area of decreased attenuation. Two patients who were studied again months later had glands which had returned to normal size. The enlarged, upwardly convex pituitary gland appears to be typical and normal for the recently post partum period.     

Anterior and posterior lobes of the pituitary gland: assessment by 1.5 T MR imaging

Pituitary glands of 60 normal volunteers (30 men 20-36 years old, and 30 women 18-42 years old) were studied by 1.5 T magnetic resonance (MR) imaging. The T1-weighted images (T1WI) [repetition time (TR) = 400 ms; echo time (TE) = 25 ms] were obtained in the coronal, sagittal, and axial planes. Proton density (PD)/T2-weighted images (PDWI/T2WI) (TR = 2,000 ms; TE = 25/100 ms) were obtained in the sagittal plane using 3 mm slice thickness. On T1WIs of all subjects the posterior part (PP) of the pituitary fossa showed the highest signal, which was indistinguishable from fatty tissue. This study reveals that this region of high signal intensity (PP) corresponds to the posterior lobe and not intrasellar fat because its shape, size, and position are compatible with the posterior lobe; its signal intensity differs from that of fatty tissue on PDWI and T2WI; the absence of an intrinsic chemical shift artifact (CSA) characteristic of fat; and due to CSA, a dorsum with fatty marrow is shifted relative to the PP (or may be made to merge with it). Regarding the differentiation of the two lobes of the pituitary gland on MR, the morphology of the anterior and posterior lobes was evaluated and great variation found. Appreciation of normal is particularly important in evaluating coronal images for small pituitary lesions.     

MR assessment of pituitary gland morphology in healthy volunteers: age- and gender-related differences.

PURPOSE AND METHODS: High-field MR images at 1.5 T were used to characterize the effects of age and gender on pituitary size and shape in a sample of 71 adult volunteers (40 females), aged 21 to 82 years. FINDINGS: For all subjects, age was inversely correlated with pituitary height (r = -.43, P less than .0002) and cross-sectional area (r = -.35, P less than .0028). Age-specific gender differences were also present in pituitary height and area. A convex upper pituitary margin was more common in females (P = .002) and younger subjects (P = .009). CONCLUSIONS: This study confirms that aging is accompanied by gender-specific changes in pituitary size and shape, and provides normative data that may facilitate evaluation of the pituitary gland in neuroendocrine disorders.     

Contrast enhanced area of posterior pituitary gland in early dynamic MRI exceeds hyperintense area on T1-weighted images.

Seventeen normal pituitary glands were studied by midline sagittal (and in one case axial) dynamic MRI before and immediately after injection of Gd-DTPA, using spin-echo sequences with a short repetition time. Images were obtained at 1 min intervals for 6 min at 1.5 T. A well-defined focal area with marked enhancement was seen in the posterior portion of the pituitary gland on the first image after injection of Gd-DTPA. The size of the early enhancing area in the posterior pituitary (EEPP) was compared with the high signal of the posterior pituitary (HSPP) on the precontrast image. The EEPP was larger than the HSPP in 10 cases (59%). The two were equal in size in seven cases (41%). The EEPP was anteriorly convex in 11 cases (65%), whereas HSPP was anteriorly convex in 4 cases (24%). We believe that EEPP closely represents the real extent of the posterior lobe. Our results support the hypothesis that HSPP may involve only a portion of the posterior pituitary.