^99Tc^m-HL91乏氧显像在恶性肿瘤治疗后随访中的应用

目的评价^99Tc^m-4,9-二氮-3,3,10,10-四甲基十二烷-2,11-二酮肟（HL91）乏氧显像在恶性肿瘤治疗后随访中的价值。方法37例胸部和头颈部恶性肿瘤患者在治疗结束后3—12个月的临床随访中,CT检查怀疑肿瘤残余、复发或转移,再行^99Tc^m-HL91乏氧显像。目测定性分析,判定乏氧显像阳性病例,再用感兴趣区（ROI）技术对阳性病例进行半定量分析,计算肿瘤部位（T）与对侧相应部位或头皮（NT）的放射性比值（T／NT）,并采用成组设计两样本均数t检验进行比较。以鼻咽内镜检查、病理活组织检查结果和12个月的临床随访资料作为判断肿瘤残余、复发或转移的依据,计算^99Tc^m-HL91显像和cT的诊断效能。结果37例患者中,无肿瘤局部残余或复发病灶者19例,存在肿瘤局部残余或复发病灶者11例,有远处转移病灶者7例。（1）无肿瘤局部残余或复发组与肿瘤局部残余或复发组的T／NT比值分别为1．18±0．14和1．58±0．16,两者差异有统计学意义（t=4．87,P〈0．001）。（2）^99Tc^m-HL91显像监测肿瘤局部残余或复发的灵敏度72．73％（8／11）,特异性89．47％（17／19）,准确性83．33％（25／30）;CT监测肿瘤局部残余或复发的灵敏度63．64％（7／11）,特异性84．21％（16／19）,准确性76．67％（23／30）。^99Tc^m-HL91显像与CT结果一致的有21例患者,^99Tc^m-HL91显像与CT联合监测此21例肿瘤残余或复发的灵敏度4／4,特异性94．12％（16／17）,准确性95．24％（20／21）。（3）7例转移患者,^99Tc^m-HL91显像阳性4例,CT均阳性。结论^99Tc^m-HL91乏氧显像对恶性肿瘤治疗后局部残余、复发或转移灶的鉴别有一定价值,与CT联合可有效提高对恶性肿瘤治疗后局部残余、复发或转移灶的早期诊断效能。     

99Tcm-HL91乏氧显像评价小鼠移植瘤放疗疗效

目的为^99Tc^m-4，9-二氮-3，3，10，10-四甲基十二烷-2，11-二酮肟（HL91）乏氧显像评价肿瘤放疗疗效提供依据。方法15只H22肝癌细胞小鼠移植瘤模型分成3组，每组各5只。A组不进行放疗；B组单次放疗25Gy后即刻进行^99Tc^m-HL91显像；C组单次放疗25Gy48h后进行^99Tc^m-HL91显像，计算B、C组放疗前后同一感兴趣区（ROI）内肿瘤组织与正常脑组织放射性计数比值（T／N）；测定A、B、C组凋亡细胞、G1期和S期细胞比例及观察肿瘤组织放疗前后病理变化。结果（1）B组放疗后T／N值较放疗前显著增高（P〈0．05）；C组放疗后T／N值较放疗前显著降低（P〈0．05）。（2）A、B、C组凋亡细胞之间比例差异具有统计学意义（P〈0．05，A〈B〈C）。（3）C组S期细胞所占比例明显低于A、B组，G1期细胞比例明显高于A、B组（P〈0．05）；C组肿瘤组织光学显微镜下可见凋亡细胞和大量细胞碎片。结论^99Tc^m-HL91显像是一种有价值的评价放疗疗效的手段。     

99Tcm-HL91 SPECT脑显像检测脑出血患者乏氧组织

目的探讨^99Tc^m-4，9-二氮-3，3，10，10-四甲基十二烷-2，11-二酮肟（HL91）脑显像检测脑出血患者脑组织乏氧的作用。方法9名健康对照者和35例脑出血患者于起病96h内行^99Tc^m-HL91SPECT脑显像和同机CT扫描，并进行图像融合。其中7例患者于第10～90天内复查SPECT显像（2例2次，5例1次）。若在同机CT显示的出血灶和（或）周围脑组织连续2个以上层面和2个以上不同轴向断层上见放射性浓聚区，且病灶／本底（IMB）放射性比值〉1．2，为乏氧显像阳性。结果（1）9名对照组受试者均未见脑皮质有异常放射性浓聚。（2）35例脑出血患者中，乏氧显像阳性15例（42．8％），乏氧灶位于出血灶和（或）周围组织，其中13例同机CT均见明显出血灶。2例治疗前血肿周围乏氧显像阴性，但治疗后乏氧显像阳性。2例患者共显像3次，随病情好转乏氧灶范围逐渐缩小，IMB比值逐渐下降。结论^99Tc^m-HL91SPECT脑显像可清楚显示脑出血后的乏氧脑组织，并证实血肿周围存在乏氧组织。     

^99Tc^m—HL91与^99Tc^m—MIBI显像在实体肿瘤和炎症模型中的对比研究

目的 用^99Tc^m-4，9－二氧－2，3，10－10－甲基甲十二烷－2，11－二酮肟（HL91）与^99Tc^m-甲氧基异丁基异腈（MIBI）行探测实体肿瘤及炎症的对比研究。方法用^99Tc^m-MIBI和^99Tc^m-HL91对3种实验性实体肿瘤（小鼠艾氏腹水癌、H22肝细胞癌、裸鼠荷人卵巢腺癌COC1）和化学性炎症、细菌性炎症模型进行平面显像，^99Tc^m-MIBI组采集早期相（10－20min)及延迟相（2h),^99Tc^m-HL91组在1及4h采集。在4h处死动物，取肿瘤组织、血液、对侧肌肉、测定每克组织放射性计数、计算靶／血、靶／非靶比值，并应用RO1技术对显像结果进行定量分析。结果 ^99Tc^m-HL91组于注射药后1及4h肿瘤清晰显像，而化学性及细菌性炎症未见显影：^99Tc^m-MIBI组肿瘤与炎症不易区分。HL91组肿瘤T／B、T／NT比值明显高于MIBI组，肿瘤T／NT比值也明显高于炎症组。结论 ^99Tc^m-HL91可用于实体性肿瘤的诊断，并可区分肿瘤与炎症，对实体性肿瘤的诊断价值明显优于^99Tc^m-MIBI。     

99Tcm-HL91乏氧显像预测局部晚期非小细胞肺癌放疗敏感性

目的 探讨99Tcm-4,9-二氮-3,3,10,10-四甲基十二烷-2,11-二酮肟(HL91)乏氧显像预测局部晚期非小细胞肺癌(locally advanced non-small cell lung cancer,LANSCLC)对放疗敏感性的临床价值.方法 对29例LANSCLC患者静脉注射99Tcm-HL91 1110MBq 后进行1 h(早期)及4 h(延迟)SPECT断层显像,根据显像进行目测和半定量分析(T/N值),并按延迟显像T/N值将患者分为低摄取组及高摄取组.所有患者均接受常规分割放射治疗, 对2组放疗近期疗效进行比较.结果 99Tcm -HL91早期和延迟显像对LANSCLC患者乏氧诊断的灵敏度分别为75.9%(22/29)、100%(29/29),二者相比有显著差异(P=0.010).半定量分析结果T/N值与不同病理类型、临床分期、病灶大小无明显关系(P＞0.05).低摄取组(T/N＜2.15,n=17)放疗近期有效率76.5%(13/17)高于高摄取组(T/N≥2.15,n=12)的33.3%(4/12),比较有显著性差异(P=0.029).结论 99Tcm -HL91显像对LANSCLC乏氧诊断具有较高的灵敏度,并在预测其放疗近期效果方面具有一定的临床价值.     

非小细胞肺癌99Tcm-HL91显像与恶性程度、HIF-1α表达的相关性

目的 探讨非小细胞肺癌^99Tc^m-4,9-二氮-3,3,10,10-四甲基十二烷-2,11-二酮肟（HL91）显像与其恶性程度、乏氧诱导因子-1α（HIF-1α）表达的关系.方法 35例非小细胞肺癌患者,注射^99Tc^m-HL91后4 h进行胸部前后位、后前位平面及断层显像,利用感兴趣区（ROI）技术,计算肿瘤与对侧正常组织（T/N）的放射性比值.所有患者均行组织病理学检查,标本行HE染色、免疫组织化学染色.结果 ^99Tc^m-HL91平面显像：35例非小细胞肺癌患者中30例显像阳性;断层显像：33例显像阳性.定量分析：4 h断层像T/N比值明显高于平面像（t=10.619,P=0.000）;HL91显像的T/N比值与肺癌细胞恶性程度相关（r=0.626,P=0.000）,鳞癌、腺癌之间的T/N比值差异无显著性（t=0.981,P=0.330）.HIF-1α主要表达于肺癌细胞胞核及胞质,肿瘤间质细胞也可见少量表达,肿瘤坏死区周围及肿瘤浸润边缘部的癌细胞HIF-1α表达明显增多.鳞癌、腺癌间的HIF-1α表达差异无显著性（ZC=1.295,P=0.730）,HIF-1α表达强弱与肺癌细胞恶性程度相关（rs=0.467,P=0.005）,与肿瘤大小无关.非小细胞肺癌各组织学分级HL91显像T/N比值与HIF-1α表达强弱均高度相关（r=0.756～0.893,P＜0.05）.结论 HL91显像的T/N比值与肺癌细胞恶性程度呈中度相关,与恶性肿瘤细胞HIF-1α表达呈高度相关.HL91显像可以用来预测肿瘤恶性程度及放、化疗疗效.     

99 Tcm-HL91 SPECT显像检测急性脑梗死乏氧脑组织的研究

目的：探讨^99Tc^m-4，9．二氮-3，3，10，10-四甲基十二烷-2，11-二酮肟(HL91)脑显像检测急性脑梗死乏氧脑组织的作用。方法：7例正常对照者和21例急性脑梗死患者于起病96h内进行脑^99Tc^m-HL91 SPECT显像和同机CT扫描，并进行图像融合，其中3例首次显像阳性的患者于第7～42天复查SPECT显像(1例3次，另2例各1次)。结果：①对照组未见脑实质有明显放射性浓集。②21例患者中，14例为完全或部分前循环梗死，乏氧显像阳性8例，阳性率为38．1％，乏氧区位于梗死灶周围。其中3例起病后7～42d病情好转者，复查SPECT乏氧显像仍呈阳性，但范围缩小。7例腔隙性梗死者乏氧显像均阴性。结论：^99Tc^m-HL91 SPECT显像可显示脑梗死后脑乏氧组织。     

99mTc-MIBI联合99mTc-HL9l乏氧显像对60例原发性肺癌的诊断评价

目的 探讨^99m Tc-甲氧基异丁基异腈（^99m Tc-MIBI）肺亲肿瘤显像联合^99m Tc-4，9-二氮-3，3，10，10-四甲基十二烷-2，11-二酮肟（^99m Tc-HL91）乏氧显像对原发性肺癌的诊断效能。方法 对60例拟诊断原发性肺癌患者，术前进行^99m Tc-MIBI及^99m Tc-HL91显像，以病理结果为金标准，分析^99m Tc-MIBI联合^99m Tc-HL91显像对原发性肺癌的诊断价值。结果 病理结果证实原发性肺癌48例，良性病变12例。^99m Tc-MIBI、^99m Tc-HL91和^99m Tc-MIBI＋^99m Tc-HL91显像对原发性肺癌诊断的灵敏度、特异度和准确率分别为89．6％（43／48）、77．1％（37／48）、95．8％（46／48），75．0％（9／12）、91．7％（11／12）、83．3％（10／12）和86．7％（52／60）、80．0％（48／60）、93．3％（56／60）。结论^99m Tc-MIBI肺亲肿瘤显像联合^99m Tc-HL91乏氧显像有助于提高对原发性肺癌的诊断效能。     

99Tcm-甲氧基异丁基异腈SPECT评价非小细胞肺癌化疗疗效

目的探讨99Tcm-甲氧基异丁基异腈（99Tcm-MIBI）SPECT评估非小细胞肺癌（NSCLC）化疗疗效的价值。方法71例NSCLC患者根据胸部CT分为化疗有效组（完全缓解＋部分缓解）和无效组（病情稳定＋疾病进展）,于化疗前行99Tcm-MIBISPECT,静脉注射99Tcm-MIBI740MBq后10～30min及2—3h分别行早期及延迟显像,在99Tcm-MIBI显像图上用感兴趣区（ROI）的方法勾画出病灶,然后选取镜像ROI于健侧肺的相应部位,由此分别获得早期相肿瘤／正常肺组织摄取比值（ER）和延迟相肿瘤／正常肺摄取比值（DR）,并计算滞留指数（RI）。采用t检验及秩和检验分析化疗有效组与化疗无效组ER、DR和RI之间的差别。结果99Tcm-MIBI显像结果中,化疗有效组的ER、DR分别为2．39±0．21、2．50±0．19,均显著高于化疗无效组的1．89±0．19、2．05±0．21,统计学差异有意义（t=8．311、8．480,P〈0．05）。化疗有效组的RI中位值为6．63％,高于化疗无效组的5．13％,统计学差异有意义（Z=2．416,P〈0．05）。结论99Tcm-MIBI显像在评估NSCLC化疗疗效方面具有重要的临床价值。     

^99Tc^m-depreotide生长抑素受体显像在肺癌诊断中的应用

目的探讨^99Tc^m-地普奥肽（depreotide）生长抑素受体显像对肺癌的诊断价值。方法52例肺部肿瘤患者[小细胞肺癌（SCLC）8例,非小细胞肺癌（NSCLC）38例,良性结节6例]静脉注射^99Tc^m-depreotide（740±60）MBq后行平面及胸部SPECT显像,并勾画感兴趣区（ROI）,计算肿瘤和对侧正常肺组织的放射性（T／N）比值,所有病灶均经病理检查证实。采用SPSS 11.5软件,行两样本t检验。结果^99Tc^m-depreotide显像诊断52例肺癌的灵敏度、特异性、准确性分别为93．5％（43／46）、5／6和92．3％（48／52）;假阴性3例,假阳性1例。3例假阴性分别为2例鳞癌、1例腺癌,1例假阳性为炎性假瘤。SCLC和NSCLC组T／N比值分别为1．948±0．282和1．280±0．160。SCLC对^99Tc^m-depreotide的摄取明显高于NSCLC（t=0．130,P〈0．05）。结论^99Tc^m-depreotide生长抑素受体显像是一种无创、安全、有效、简便的检查方法,对肺癌尤其是SCLC有良好的诊断价值。     

Stress MR imaging for evaluation of popliteal artery entrapment

The popliteal artery entrapment (PAE) syndrome has been recognized as a cause of arterial occlusion in young people. It is the result of an anomaly of the relationship between the popliteal artery and the gastrocnemius muscle. Eight young healthy volunteers (16 legs) and six patients (10 legs) with suspected PAE underwent magnetic resonance (MR) imaging. Gradient-echo images were obtained in axial planes with the leg at rest and during active plantar flexion against resistance. Imaging at rest allowed identification of PAE signs in only one leg, which had an anomalous medial course of the popliteal artery. In the other cases, only the stress technique was able to show signal loss in the popliteal artery due to muscular compression (two legs) or the presence of accessory muscle slip around the vessel (two legs), as confirmed at surgery. MR imaging is therefore a useful technique for the diagnosis of PAE because of its capability of combining information obtainable with other modalities.     

MR imaging of muscle and tender points in fibromyalgia

Fibromyalgia is a syndrome manifested by chronic, diffuse muscu-loskeletal aching and soreness, palpable muscle tender points, and other symptoms. Standardized clinical diagnostic criteria have recently been developed. Skeletal muscle has been postulated as the end organ in this disease. Biochemical, histologic, electromyographic, and conventional radiographic studies have demonstrated no definitive abnormality. This study sought to establish whether magnetic resonance (MR) imaging could demonstrate any abnormality in these patients. Eighteen patients were entered in the study, 14 of whom were able to complete their examinations. T1 -weighted, T2-weighted, gradient-echo, and STIR (short-tau inversion-recovery) sequences were performed in all patients, with selected patients examined with T1weighted, gadopentetate dimeglu-mine-enhanced sequences. The trapezius and suboccipital regions were imaged in patients who, clinically, had active fibro-myalgia. No abnormalities could be detected. The authors conclude that the conventional MR imaging used in this study was unable to depict any primary skeletal muscle abnormality in fibromyalgia.     

Controversies in cervical spine imaging in trauma patients

No area of emergency radiology has generated as much discussion in recent years as the subject of cervical spine imaging for trauma patients. This review will be in three parts. The first will examine the indications for cervical imaging and will focus on those factors that make patients at high risk or low risk for cervical injury. The second part will discuss the merits of radiography and computed tomography as the main screening diagnostic examination. In addition to the roles of each modality in the evaluation process, such factors as efficacy of diagnosis, time (duration) of study, and cost will be discussed. Finally, the third part will explore the methods currently employed to clear the cervical spine in comatose patients.Presented at the Annual Meeting of the American Society of Emergency Radiology, Las Vegas, Nevada, 22–25 October, 2003     

Uterine contractions: Possible diagnostic pitfall at MR imaging

A total of 206 nongravid patients with various gynecologic problems underwent pelvic magnetic resonance (MR) examinations that included both sagittal T2-weighted and contrast agent–enhanced T1-weighted images. MR images were retrospectively reviewed to identify changes in endometrial configuration on serial images obtained during the same MR examination. In 20 MR examinations (all in women of reproductive age), endometrial distortion due to myometrial bulging was noted on T2-weighted or contrast-enhanced T1-weighted images. It was absent on other MR images obtained at different times. Myometrial bulging exhibited low signal intensity in 18 examinations. The finding resembled adenomyosis or leiomyoma on T2-weighted or contrast-enhanced T1-weighted images. These results evidence the presence of transient myometrial bulging and transient low-intensity myometrium in the nongravid uterus. This phenomenon is thought to represent uterine contraction. Clinicians should be aware of the potential presence of transient low-signal-intensity myometrial bulging that could present diagnostic problems in the normal uterus.     

Brodie Abscess: MR imaging appearance in 10 patients

The magnetic resonance (MR) imaging features of Brodie abscess have not yet been fully evaluated. Ten patients with Brodie abscess, eight of long bone and two of vertebra, were studied with MR imaging. Long bone abscess had a characteristic “target” appearance with four layers: (a) a center with low signal intensity on T1-weighted images and high signal intensity on T2-weighted and STIR (short-inversion-time inversion recovery) images, (b) an inner ring isointense to muscle on T1-weighted images and with high signal intensity on T2-weighted and STIR images, (c) an outer ring hypoin-tense on all images, and (d) a peripheral halo hypointense on T1-weighted images. In six of eight cases, a soft-tissue mass was found. The two vertebral abscesses had a less specific appearance, with low signal intensity on T1-weighted images and high signal intensity on T2-weighted and STIR images. Only the peripheral halo was clearly identified in both cases.     

Dynamic contrast-enhanced MR imaging assessment of vascularized free fibular grafts

Magnetic resonance (MR) imaging may be a noninvasive method for assessing perfusion of vascularized bone grafts placed for treatment of avascular necrosis. One proximal femur of seven beagles was devascularized, with insertion of a vascularized fibular graft. MR imaging at 1 week (seven dogs) and 6 weeks (five dogs) after surgery included pre- and postcontrast spin-echo sequences, unenhanced twodimensional time-of-flight (TOF) vascular imaging, and dynamic gradient-echo imaging during infusion of gadolinium. Relative signal intensity values of selected regions obtained from the dynamic gradientecho images were plotted as percent enhancement versus time. In the operated hip, MR imaging did not show enhancement in six of seven femoral heads and greater trochanters at 1 week after surgery, with similar results after 6 weeks. MR imaging of fibular grafts 6 weeks after surgery showed an initial rapid increase in enhancement and a subsequent slower increase in five of five dogs, although no enhancement was seen in six of seven dogs at 1 week. These findings contrasted with a rapid initial increase in enhancement followed by slow decline in non-operated hips. Two-dimensional TOP imaging did not show the vascular pedicle of the graft in any dog. Findings of radionuclide bone scanning performed 1 week after surgery were consistent with devascularization of the operated femur and fibular graft. However, tetracycline distribution and histologic findings confirmed the viability of five of five grafts within the devascularized femurs 6 weeks after surgery. Thus, dynamic contrast-enhanced MR imaging at 6 weeks after surgery is valuable for assessing vascular bone graft perfusion, while similar imaging at 1 week may suggest otherwise.     

Adrenal tissue characterization with 0.5-T MR imaging: Value of T2*-weighted images

The authors investigated the value of magnetic resonance (MR) imaging at 0.5 T for distinguishing adrenal adenomas from adrenal metastases. The series included 23 adrenal adenomas (18 nonhyperfunctioning, five hyperfunctioning) and 23 adrenal metastases from various organs. Adrenal tumor–liver signal intensity ratios on T1-, T2-, and T2*-weighted images were calculated for adrenal tissue characterization. Adrenal adenomas were more precisely distinguished from adrenal metastases on T2*-weighted images (21 of 23, 91%) than on T2-weighted images (15 of 23, 65%). T1-weighted images were not useful for this distinction. In conclusion, T2*-weighted images were better than routine T2-weighted images for distinguishing adrenal adenomas from adrenal metastases. It can be postulated that the total signal intensity of adrenal adenomas, which contain some fat components, decreased on T2*-weighted images because of an out-of-phase effect.     

Right-side aortic arch with aneurysm of aberrant left subclavian artery: MR imaging appearance.

Reports of aneurysms of the subclavian artery in both normal and anomalous aortic arches have been rare. The authors describe a patient with a right-side aortic arch and an aneurysm of the aberrant left subclavian artery, which, to the authors' knowledge, is a previously unreported association. At presentation, the aneurysm appeared as a calcified left superior mediastinal mass. Magnetic resonance imaging enabled preoperative diagnosis and guided surgical planning.     

MR angiography of congenital heart disease: Value of segmented two-dimensional inflow technique and maximum-intensity-projection display

Magnetic resonance (MR) angiography of the cardiovascular system was evaluated in 41 patients with congenital heart disease by using a two-dimensional (2D) inflow technique based on a magnetization-prepared gradient-echo pulse sequence with segmented k-space data acquisition and electrocardiographic gating at 0.5 T. Inversion and saturation prepulses were used to suppress stationary tissue and enhance intravascular signal. Presaturation slabs were applied where certain vascular structures had to be suppressed. Sequence parameters were optimized by evaluating signal intensity and contrast characteristics for various flip angles and inversion and saturation delay times. The heart and intrathoracic vasculature were encompassed with 40–50 overlapping sections. Both 2D angiograms and maximum-intensity-projection images were evaluated. Combining data sets acquired in the sagittal and transverse orientations provided the most satisfactory information about the pulmonary arteries. The highest signal-to-noise ratios were obtained with a flip angle of 65° and short prepulse delay times. Two-dimensional MR angiography can provide useful diagnostic information but requires a thorough understanding of in-plane and hemodynamically induced signal intensity changes.