肝脏快速容积采集动态增强扫描对前列腺癌的诊断价值及与血管生成对照分析

目的:探讨肝脏快速容积采集技术(LAVA)动态增强扫描对前列腺癌的诊断价值,并结合病理初步分析前列腺病变与血管生成的相关关系。方法:回顾性分析经穿刺活检及手术病理证实的前列腺癌和前列腺增生各40例的MRI表现,术前均行MRI常规平扫和LAVA动态增强扫描,观察病灶LAVA动态强化特征并获得TIC,分析其参数变化,同时对证实的病理标本行血管内皮生长因子(VEGF)和微血管密度(MVD)测定。结果:病变TIC分为3型:Ⅰ型为缓慢强化型,Ⅱ型为平台型,Ⅲ型为速升下降型;Ⅰ型多见于前列腺增生,Ⅱ型既可见于前列腺癌,又可见于前列腺增生,Ⅲ型以前列腺癌为主。前列腺癌组病灶强化峰值时间早于前列腺增生组,强化程度和强化率均高于前列腺增生组(均P0.05)。前列腺癌组MVD值及VEGF表达明显高于前列腺增生组(均P0.05)。结论:LAVA动态增强扫描强化特征有助于前列腺增生与前列腺癌的诊断与鉴别诊断,且能反映前列腺癌及前列腺增生血管生成的不同状况。     

MRI动态增强扫描在前列腺癌诊断及鉴别诊断中的价值

目的　探讨动态增强MRI对前列腺癌诊断及鉴别诊断的价值。方法　对经病理证实的前列腺癌 10例及前列腺增生 30例行常规平扫及动态增强和延迟增强扫描 ,观察病灶的信号变化并绘制时间 /信号强度曲线。结果　前列腺癌在动态增强过程中 5例为早期强化 ,4例虽强化不显著 ,但与周围组织的信号差别增大 ,其时间 /信号强度曲线峰值位于早期及中期 ,1例灶性癌变者增强前后均未见明确癌灶 ;而前列腺增生表现为逐渐强化 ,峰值多位于晚期。结论　动态增强MRI使前列腺癌与周围组织的信号差别增大 ,有助于观察病灶 ;时间 /信号强度曲线在前列腺癌与增生的鉴别方面有一定价值     

前列腺磁共振成像中动态增强容积采集技术的应用

目的：运用磁共振肝脏快速容积采集技术（LAVA）行前列腺成像,探讨该技术的临床应用价值。方法：回顾性分析22例经活检证实的前列腺病变患者的LAVA扫描各期图像。结果：所有患者均获得分辨力高、病灶显示满意的各期图像。15例前列腺癌MRI平扫表现为不同程度的前列腺增生肥大,T1WI呈高信号,外围叶内可见团片状低信号影,动态增强时在动脉早期即出现斑片样强化,稍后强化更明显,与未强化之外围叶形成明显对比,静脉期则强化减弱,仅可见边缘部分强化,延迟扫描随着正常外围叶组织强化,肿瘤与周围组织的信号对比差别远较前期减少。结论：磁共振LAVA技术能清晰显示中央叶、外围叶以及包膜结构,获得高分辨力、高信噪比及诊断准确的图像,且操作简便,在前列腺癌的诊断和鉴别诊断中具有很高的临床价值。     

MRI LAVA 技术在原发性肝癌诊断中的价值

目的 探讨应用3.0 T MR肝脏三维容积快速扫描(liver acceleration volume acquisition,LAVA)技术对原发性肝癌的诊断价值.方法 对105 例经实验室检查,手术病理或介入证实为原发性肝癌患者的MRI资料回顾性分析.分别进行常规自旋回波序列(T2WI、T1WI),LAVA序列增强多期扫描及T1WI常规增强扫描,观察常规增强序列及LAVA 序列病灶显示数目及MRI征象,统计检出率及定性率.结果 经手术病理或介入证实共有病灶154个,常规增强扫描检出137个 (88.9% ),LAVA序列增强多期扫描检出154个 (100% );常规增强扫描定性130个(84.4%),LAVA序列增强多期扫描定性144个(93.5%).结论 磁共振LAVA序列多期动态增强对于原发性肝癌的诊断、治疗及预后具有指导意义.     

磁共振动态增强扫描SI-T曲线对前列腺良恶性病变的鉴别诊断

目的探讨磁共振动态增强扫描(DCE-MRI)信号强度-时间曲线(signal intensity-time curve,SI-T曲线)对前列腺良恶性病变的鉴别诊断价值。方法对30例经病理证实的前列腺癌(Pca)患者和32例良性前列腺增生(BPH)患者行MRI平扫,动态增强扫描及延迟扫描,观察病变的MRI表现特征并分别绘制前列腺癌病灶和增生结节的SI-T曲线,重点分析其信号强度变化及SI-T曲线的走形趋势。结果在磁共振动态增强扫描早期Pca癌灶和BPH增生结节均呈明显强化,有助于病变的检出。SI-T曲线参数:峰值时间Pca组早于BPH组,强化程度和强化率Pca组均高于BPH组(P<0.05)。结论磁共振动态增强扫描SI-T曲线对BPH和Pca的鉴别诊断有较明确的价值。     

动态螺旋CT增强诊断前列腺癌和增生

目的　研究动态螺旋CT增强对前列腺癌和增生的诊断 ,提高CT对前列腺疾病的检出率。方法　前列腺疾患和盆腔其他疾患男性患者共 88例常规平扫 ,再行动态螺旋CT增强扫描 ,回顾观察经病理证实、资料完整的 5例前列腺癌和 11例前列腺增生的影像资料 ,着重研究病灶增强情况并加以比较分析。结果　除 1例前列腺癌和 3例前列腺增生患者前列腺不大外 ,其余病例均有不同程度增大 ,所有前列腺癌和 1例前列腺增生患者前列腺形态不完整。动态螺旋CT增强扫描前列腺癌动脉期为等或略低密度灶 ,静脉期为低密度灶 ,10例前列腺增生患者动脉期显示中央区弥漫不均匀性强化 ,两侧叶区明显 ,静脉期显示中央区进一步强化 ,双期外周区未强化 ,中央区与外周区比例增大 ;1例前列腺外形不大的前列腺增生患者动脉期、静脉期中央区局限斑点状强化 ;8例前列腺增生患者行延时扫描 ,其前列腺中度均匀强化。结论　前列腺癌和增生的动态螺旋CT增强病灶密度变化有一定特征性 ,可资鉴别 ,有助于定性诊断     

肛瘘磁共振LAVA增强扫描的临床应用与评价

目的评价肛瘘MRI肝脏容积加速采集(LAVA)增强扫描的临床应用价值。方法分析27例手术治疗患者的肛瘘资料,以手术结果对照,比较MRI平扫、LAVA增强扫描、直肠腔内超声之间的差异。结果在肛瘘内口位置和数目检出与手术结果符合率方面,MRI平扫相似文献   

MRI动态增强检查在前列腺癌诊断的价值

目的：分析前列腺癌动态扫描的影像学表现，以提高对本病诊断准确率。资料与方法：回顾性分析手术病理证实的前列腺癌患者20例，患者术前均做MRI平扫十动态增强检查，平扫包括T1W1横断位、冠状位、矢状位成像及横断位T2W1，将动态增强后T1w1分别与平扫T1W1、T2W1进行对照，以比较确定肿瘤位置、大小、形态、及肿瘤穿破包膜及周围脏器侵范的显示情况。结果：MRI动态增强大部分肿瘤组织可见早期强化，与正常前列腺信号差异增大，相对平扫其对肿瘤大小、形态、范围的显示提高、对肿瘤侵犯周围结构显示能力有较明显提高。结论：MRI动态增强扫描对前列腺癌的诊断及周围侵犯情况具有重要意义。     

MRI对前列腺癌的诊断与分期

目的：探讨高场强MRI在前列腺癌的诊断和分期中的作用。方法：回顾性分析经手术病理证实的26例前列腺癌的高场强MRI资料,并与病理结果和临床分期对照。结果：26例前列腺癌中MRI诊断前列腺炎2例,前列腺增生4例,前列腺癌20例,其中B期5例,C期13例,D期2例,定性诊断符合率为76.9%,20例前列腺癌分期符合率为85%;典型的前列腺癌在T1像呈稍低信号,与正常前列腺组织接近,在T2像上表现为正常较高信号的周围带内出现异常低信号灶,增强扫描多数早期较明显强化。结论：高场强MRI对前列腺癌诊断与分期有重要价值。     

LAVA整合ASSET在肝血管成像中的应用价值

目的：探讨肝脏快速容积采集（LAVA）整合阵列空间敏感编码技术（ASSET）在肝血管成像中的价值。方法：对80例肝病患者行肝脏常规MRI平扫及增强扫描。增强扫描采用LAVA整合ASSET;将LAVA采集的原始图像行最大强度投影（MIP）处理并分析其对肝脏病变及肝血管关系的显示情况。结果：80例肝脏病灶全部清晰显示。其中,肝癌42例44个,显示肿瘤血管30例,肿瘤供血动脉明显增粗、变形、移位20例,门静脉受侵25例,门静脉癌栓6例;肝血管瘤5例,肝囊肿8例,轻度肝炎6例,肝硬化18例,胆总管下段乳头状瘤1例。MIP显示肝动脉3级以上分支76例（95%）、门静脉3级以上分支72（90%）及肝静脉3级以上分支64例（80%）。结论：LAVA整合ASSET在肝脏动态扫描中可在较短时间内获得多期高质量增强图像并提供血管解剖信息,具有较高临床应用价值。     

Local staging of prostate carcinoma with endorectal coil MRI: correlation with whole-mount radical prostatectomy specimens

The purpose of this study was to investigate the accuracy of endorectal coil MRI in the local staging of prostate carcinoma. A total of 73 patients with biopsy-proven prostate carcinoma were examined at 0.5 T prior being submitted to radical prostatectomy. The gold standard was provided in all patients by findings at whole-mount sectioning of the surgical specimens. At pathology 28 patients had stage T2, 30 had stage T3a/b, and 15 had stage T3c lesions. Overall accuracy of endorectal coil MRI in defining local tumor stage was 82% (60 of 73 patients). Of 73 patients, 5 (7%) were underestimated and 8 (11%) overestimated. The sensitivity and the specificity of endorectal coil MRI in diagnosing capsular penetration were 95% and 82%, respectively. Seminal vesicle invasion was detected with 80% sensitivity and 93% specificity. Our data indicate that endorectal coil MRI is an accurate method for local staging of prostate cancer.Correspondence to: C. Bartolozzi     

前列腺MRS诊断外周带前列腺癌的价值

目的：分析前列腺外周带的MRS特征,探讨MRS技术及其在外周带前列腺癌诊断中的价值。方法：24例临床及常规MRI检查拟诊局限性前列腺外周带前列腺癌患者均成功行前列腺MRS检查,所有患者均经病理证实为前列腺癌,其中19例行穿刺活检,5例经手术证实。回顾性分析患者的临床资料、病变部位、大小、常规MRI特征、MRS检查结果,计算（胆碱＋肌酸）/枸橼酸盐（CC/C）。采用重复测量方差分析比较正常外周带与前列腺癌组织CC/C值差异。采用操作者工作特征曲线（ROC）分析CC/C值诊断前列腺癌的价值。结果：早期外周带前列腺癌T2WI表现为在外周带高信号内有局灶性低信号区。MRS示前列腺外周带肿瘤组织枸橼酸盐（Cit）峰明显下降,胆碱（Cho）峰升高,CC/C值为1.40±0.33,正常外周带为0.51±0.12,两者差异有统计学意义（F=95.189,P〈0.001）。CC/C值的ROC曲线下面积为0.994,这一指标可用于判断前列腺癌（P=0.002）;以0.85为阈值时,诊断前列腺癌的敏感度为95%,特异度为100%。结论：前列腺MRS检查能反映早期外周带前列腺癌的代谢变化,对常规MRI无法明确诊断的前列腺癌具有重要诊断价值。     

Clinical and in vitro magnetic resonance imaging of prostatic carcinoma

Magnetic resonance imaging (MRI) of the prostate was accomplished in 10 patients who subsequently had surgical exploration for histologic confirmation and tumor staging. Eight patients were found to have carcinoma of the prostate. Two patients had malignancies of the urinary bladder and were treated with radical resection of the bladder and prostate. The prostatic glands in the latter two patients were free of tumor. One gland was entirely normal; the other had extensive acute and chronic prostatitis. Two resected prostates with carcinoma and one normal prostate were available for in vitro MRI in a clinical magnetic resonance unit. The MRI finding of prostatic carcinoma was heterogeneous signal patterns, seen best on T2-weighted studies. A similar pattern was identified in the gland with acute and chronic prostatitis. There was a homogeneous MRI signal pattern of the normal prostate gland examined in vitro. In two instances, the MRI studies were accurate for the identification of tumor spread to the seminal vesicles, not diagnosed at the time of surgical resection. Microscopic metastatic disease of the lymph nodes in four patients was not identified by MRI.     

The transrectal ultrasound and MRI appearances of granulomatous prostatitis and its differentiation from carcinoma

AIMS AND METHODS: Granulomatous prostatitis is a benign inflammatory condition of the prostate which can be mistaken for prostatic carcinoma both clinically and on ultrasound, but is distinguishable histologically. The transrectal ultrasound (TRUS) and magnetic resonance imaging (MRI) appearances of 10 patients with histologically confirmed granulomatous prostatitis were evaluated to try and identify any correlation between the two techniques or any specific features on MRI to help distinguish it from carcinoma. Clinical findings and serum prostatic specific antigen (PSA) levels were also evaluated. RESULTS: In five patients, both TRUS and MRI were concordant, showing only changes of benign prostatic hypertrophy (three patients) or showing no abnormality (two patients). In a further three patients, both TRUS and MRI were abnormal, with appearances suggestive of carcinoma. One of these patients had tuberculous prostatitis and had a past history of tuberculosis. In the remaining two patients, there was a discrepancy between TRUS and MRI findings, carcinoma being suspected on TRUS in one with a normal MRI, and carcinoma suspected on MRI in the other with a normal TRUS. CONCLUSION: There is no pattern of clinical, biochemical, ultrasound or MRI findings that allows a specific diagnosis of granulomatous prostatitis to be made, or differentiation from prostatic carcinoma.     

Magnetic resonance with endorectal coil in the local staging of prostatic carcinoma. Comparison with histologic macrosections in 40 cases]

PURPOSE: Endorectal coil MRI is widely used in the diagnostic workup of prostate cancer, but diagnostic accuracy rates reported in the literature are quite variable. We report our personal experience with endorectal coil MRI in the local staging of prostate carcinoma. MATERIAL AND METHODS: Forty consecutive patients with histologically proved prostate carcinoma were examined with endorectal coil MRI at high field strength (1.5 T). All patients underwent a sagittal T1-weighted SE location sequence (TR 400, TE 20), an axial T1-weighted SE (TR 400, TE 20), two axial T2-weighted FSE sequences (TR 3000, TE 102, ETL 8) with and without fat suppression, and a coronal T2-weighted FSE sequence (TR 3000, TE 102, ETL 8); an axial Fast Multiplanar Spoiled Gradient Recalled (FMSPGR) dynamic sequence after Gd-DTPA injection was also performed in 18 patients. MR staging of local tumor spread was done according to the current literature criteria. All patients were submitted to radical prostatectomy, and histologic macrosections on the same plane as MR images were obtained from surgical specimens. MR and histologic staging were compared to assess MR accuracy in detecting capsular infiltration, seminal vesicles and apex involvement. The diagnostic yield of Gd-DTPA was also investigated. RESULTS: MRI correctly staged 31 of 40 cases (77.5%). MR accuracy was 80% in detecting capsular infiltration (85.7% sensitivity and 73.6% specificity), 90% in seminal vesicle involvement (91.6% sensitivity, 89.2% specificity) and 72.5% in apex involvement (79.1% sensitivity, 62.5% specificity). Dynamic studies with Gd-DTPA did not improve staging accuracy in any case. DISCUSSION AND CONCLUSIONS: In agreement with most of the current literature, MRI showed moderate overall accuracy in the local staging of prostate carcinoma. Particularly, MRI had good accuracy in detecting seminal vesicle involvement but moderate sensitivity and specificity in demonstrating capsular infiltration and apex involvement. Due to its high cost, MRI should not be routinely used in prostate cancer staging but should be reserved to the patients whose clinical and serological data suggest extraprostatic tumor spread, whose preoperative demonstration could avoid noncurative surgery.     

前列腺癌MRI及CT征象的敏感性分析

目的：比较分析MRI及CT显示前列腺癌征象的敏感度。方法：回顾性分析20例经病理证实的前列腺癌患者的MRI及CT图像并与病理结果进行对照,CT均行平扫加增强扫描及MPR重建;MRI行常规轴面、矢状面及冠状面扫描。结果：MRI及CT均显示19例前列腺体积增大;10例侵犯精囊,2例侵犯膀胱,2例侵犯直肠前壁,盆腔区域淋巴结转移3例,髂骨转移1例;CT显示密度不均匀者18例,含小钙化者2例,4例包膜未受侵犯;MRI显示所有病例信号不均匀,少量出血1例;2例包膜未受侵犯。结论：MRI对病灶的信号改变敏感,对病灶内合并少量出血时更敏感,较CT对包膜侵犯有更高的敏感度,但对微小的包膜侵犯诊断的敏感度低,CT对小钙化较敏感,CT及MRI对于前列腺中央区的小癌灶均不敏感。     

Functional characterization of prostate cancer by integrated magnetic resonance imaging and oxygenation changes during carbogen breathing

OBJECTIVE: The objective of this study was to evaluate the changes in oxygenation of prostate cancer induced by carbogen breathing using blood oxygen level-dependent (BOLD) magnetic resonance image (MRI) with an endorectal coil (eMRI). MATERIALS AND METHODS: In 32 patients with biopsy-proven prostate cancer, endorectal MRI was performed at 1.5 Tesla using the BOLD method. Images were acquired during 4 x 4-minute episodes alternating between room air and carbogen (95% O2/5% CO2) breathing. In each episode, 40 images were acquired (T2*-weighted EPI sequence, 12-14 slices, 3-mm thickness). All patients underwent radical prostatectomy; BOLD-MRI findings were correlated with the histopathologic results. RESULTS: BOLD-MRI could be evaluated in 29 patients, and revealed heterogeneous signal changes of normal prostate and cancer tissue similar to the heterogeneity of prostate tissue in anatomic/pathologic preparation. A significant signal intensity increase (P = 0.004) was found in normal central gland and peripheral zone during carbogen breathing. Signal enhancement in carcinoma was significantly lower (P = 0.004) compared with the contralateral normal side. CONCLUSION: Intrinsic blood-tissue contrast-functional MRI during carbogen breathing may help detect and characterize prostate carcinoma from normal tissue, particularly in small 1-sided carcinomas. This may be useful for identifying candidates for radiotherapy and monitoring noninvasive therapeutic approaches.     

Interobserver Comparison of CT and MRI-Based Prostate Apex Definition Clinical Relevance for Conformal Radiotherapy Treatment Planning

BACKGROUND: CT is widely used for conformal radiotherapy treatment planning of prostate carcinoma. Its limitations are especially at the prostatic apex which cannot be separated from the urogenital diaphragm. The aim of this study was to compare the localization of the prostatic apex in CT and axial MRI to the sagittal MRI in an interobserver analysis. PATIENTS AND METHODS: 22 patients with pathologically proven prostatic carcinoma were included in the analysis. In all patients sagittal and axial T2-weighted MRI and conventional CT were performed. The position of the MRI and CT apices were localized independently by three observers in relation to the intertrochanteric line. Additional subjective judgment of the ability to define the apical border of the prostatic gland was performed by a five-scaled score. RESULTS: The apex of the prostate could be discriminated statistically significant (p < 0.001) better in the MRI as compared to CT with best judgement for the sagittal MRI. The interobserver variation for the definition of the prostatic apex was statistically significant (p = 0.009) smaller for the sagittal MRI compared to axial MRI and CT. On the average the apex as determined by sagittal MRI, axial MRI and CT was located 29 mm, 27 mm and 24 mm above the intertrochanteric line. The apex defined by CT would have led to an additional treatment of 6-13 mm in 10/22 patients compared to the sagittal MRI, defined by axial MRI only in five patients. CONCLUSION: Additional MRI provides a superior anatomic information especially in the apical portion of the prostate. It should be recommended for every single patient in the treatment planning process. It helps to avoid an unnecessary irradiation of healthy tissue and could lead to a decrease of anal side effects and radiation-induced impotency due to a reduction of the extent of irradiated penile structures.     

Feasibility study of CT perfusion imaging for prostate carcinoma

Objective

The aim of this feasibility study was to obtain initial data with which to assess the efficiency of perfusion CT imaging (CTpI) and to compare this with magnetic resonance imaging (MRI) in the diagnosis of prostate carcinoma.

Materials and methods

This prospective study involved 25 patients with prostate carcinoma undergoing MRI and CTpI. All analyses were performed on T2-weighted images (T2WI), apparent diffusion coefficient (ADC) maps, diffusion-weighted images (DWI) and CTp images. We compared the performance of T2WI combined with DWI and CTp alone. The study was approved by the local ethics committee, and written informed consent was obtained from all patients.

Results

Tumours were present in 87 areas according to the histopathological results. The diagnostic performance of the T2WI+DWI+CTpI combination was significantly better than that of T2WI alone for prostate carcinoma (P?Conclusion CTp may be a valuable tool for detecting prostate carcinoma and may be preferred in cases where MRI is contraindicated. If this technique is combined with T2WI and DWI, its diagnostic value is enhanced.

Key Points

? Perfusion CT is a helpful technique for prostate carcinoma diagnosis. ? Colour maps allow easy and rapid visual assessment of the functional changes. ? Colour maps of prostate carcinoma provide information about in vivo tumoral vascularity. ? CTp images may be added into routine radiological examinations. ? CTp provides guidance for histopathological correlation if biopsy is scheduled.     

Prostate cancer transrectal HIFU ablation: detection of local recurrences using T2-weighted and dynamic contrast-enhanced MRI

The objective was to evaluate T2-weighted (T2w) and dynamic contrast-enhanced (DCE) MRI in detecting local cancer recurrences after prostate high-intensity focused ultrasound (HIFU) ablation. Fifty-nine patients with biochemical recurrence after prostate HIFU ablation underwent T2-weighted and DCE MRI before transrectal biopsy. For each patient, biopsies were performed by two operators: operator 1 (blinded to MR results) performed random and colour Doppler-guided biopsies (“routine biopsies”); operator 2 obtained up to three cores per suspicious lesion on MRI (“targeted biopsies”). Seventy-seven suspicious lesions were detected on DCE images (n?=?52), T2w images (n?=?2) or both (n?=?23). Forty patients and 41 MR lesions were positive at biopsy. Of the 36 remaining MR lesions, 20 contained viable benign glands. Targeted biopsy detected more cancers than routine biopsy (36 versus 27 patients, p?=?0.0523). The mean percentages of positive cores per patient and of tumour invasion of the cores were significantly higher for targeted biopsies (p?<?0.0001). The odds ratios of the probability of finding viable cancer and viable prostate tissue (benign or malignant) at targeted versus routine biopsy were respectively 3.35 (95% CI 3.05–3.64) and 1.38 (95% CI 1.13–1.63). MRI combining T2-weighted and DCE images is a promising method for guiding post-HIFU biopsy towards areas containing recurrent cancer and viable prostate tissue.