分子医学影像研究进展(上)

分子医学影像技术应用影像学的方法对活体状态下的生物过程进行细胞和分子水平的定性与定量研究,极大地改变着我们对于生理作用机制、药物研发、疾病诊断与评估方面的认识角度和研究方法。本文综述了其核心技术的研究进展与应用分析,指出分子医学影像技术在生物医学工程研究和临床诊断中的重要性。     

小探头超声内镜联合多层螺旋CT术前预测胃黏膜下肿瘤切除方式的临床价值*

目的探讨小探头超声内镜(MPS)联合多层螺旋CT(MSCT)术前预测胃黏膜下肿瘤(SMT)切除方式的价值。方法回顾性分析胃SMT临床病理特征、MPS联合MSCT特征及手术方式等资料。结果共40例胃SMT。其中,男16例,女24例,平均年龄(54.0±14.2)岁。胃底SMT占52.5%,基于MPS及MSCT特征,术前诊断胃腔内生长型37例,胃腔内外生长型2例,腔外生长型1例,除外1例副脾外术后均获得证实,MPS联合MSCT对胃SMT生长方式诊断准确率97.5%(39/40)。MPS提示来源于固有肌层低回声占37例,黏膜下层3例,除外1例副脾外,MPS联合MSCT术前对肿瘤来源层次判断准确率为97.5%(39/40)。MPS诊断间质瘤36例,术后病理证实为间质瘤27例,MPS诊断间质瘤准确率75.0%(27/36)。30例选择内镜切除术,内镜手术成功率96.7%(29/30),1例中转腹腔镜手术,内镜切除瘤体直径0.5~5.0 cm,平均(1.7±1.0)cm。腹腔镜切除11例,成功率100.0%(11/11),瘤体直径2.0~7.5 cm,平均(4.3±1.8)cm。与腹腔镜手术比较,内镜切除瘤体大小明显小于腹腔镜手术(P0.05),术后平均住院日明显短于腹腔镜(P0.05),两种切除方式术后随访均未见复发。结论 MPS联合MSCT术前诊断SMT肿瘤来源层次、生长方式、诊断准确率高,能够有效指导肿瘤切除方式的选择。     

64排螺旋CT冠脉成像与冠脉造影对心肌桥诊断的比较

目的 评价64排CT冠脉成像(CTA)及冠脉造影对心肌桥的诊断对照.方法选择我院2010年~2013年间100例临床怀疑冠心病,经冠脉CTA及冠脉造影检查的患者,然后对冠脉CTA及冠脉造影的结果进行对比分析.结果 本组经冠脉CTA检出心肌桥16例病例中,冠脉造影只检出6例.结论 64排冠脉CTA对心肌桥的检出率明显高于冠脉造影.64排CT冠脉成像可以清晰而且直观地显示冠状动脉及其细小分支,并精确显示血管的走行情况、管壁的粥样斑块及钙化、血管的狭窄程度等,与目前诊断冠脉的金标准冠脉造影相比,本检查方法不但对心肌桥的检出率明显高于前者,而且为无创性检查、费用低廉.冠脉GTA可以作为冠心病高危人群无创性筛选检查及冠脉支架、搭桥术后随访手段.     

低剂量CT与4肿瘤标记物联合检测对肺癌高危人群筛查的研究

目的：评价低剂量螺旋CT（low dose spiral computed tomography,LDCT）扫描联合4种肺癌肿瘤标记物(人多效蛋白PTN、神经元特异烯醇化酶NSE、细胞角质蛋白Cyfra21-1及癌胚抗原CEA)检测对肺癌高危人群早期肺癌筛查的阳性率及特异性。方法分析及统计2011年-2013年进行LDCT扫描及肿瘤标志物联合筛查肺癌高危人群体的检查结果,并与常规早期肺癌筛查研究结果进行比较分析。结果 LDCT与常规剂量CT扫描肺部阳性检出率及病变影像学表现基本一致,无统计学差异（P＞0.05）,而辐射剂量明显下降,是常规剂量的6.38%(P<0.05);4种肺癌肿瘤标记物联合检测肺癌的敏感性约95%、特异性约80%,对诊断早期肺癌具有重要意义,4种肺癌肿瘤标记物对本实验组阳性率为1.58%（6例）,最终确定早期肺癌的为1.05%（4例）,LDCT在本实验组中检出病灶阳性率为12.1%（46例）,其中8例影像诊断为早期肺癌（2.11%）,最终仅4例（1.05%）确诊为早期肺癌,存在影像诊断假阳性。本研究共759人参与,其中LDCT和肿瘤标志物联合检测组（379例,女：176例,平均年龄54.3岁,慢阻肺患者7例;男：203,平均年龄57.6岁,慢阻肺患者26例）筛查肺部阳性率12.1%（46例有肺部CT阳性表现,6例肿瘤标记物联检均呈阳性,4例确诊为肺癌）。结论 LDCT与肺癌肿瘤标志物两种检查方法优势互补,早期肺癌检出率为1.05%,避免单项检查的假阳性事件发生,联合检测更有利于早期肺癌的早期发现及定性诊断。     

术前 CT 平扫指导跟骨骨折闭合复位内固定的临床疗效观察

目的：探讨术前 CT 扫描指导跟骨骨折闭合复位术中固定方式的临床意义。方法对拟行手术的 SandersⅡ～Ⅲ型跟骨骨折患者36例,分为闭合复位空心螺钉内固定组18例、切开复位钢板内固定组18例,对闭合复位内固定进行患侧 CT 扫描,了解骨折具体移位形态,指导术中螺钉植入方式,并对术后3 d 及术后6个月的跟骨 bohler’s 角及跟骨高度进行测量、比较,并对跟骨功能进行 AOFAS（美国足踝外科学会踝—后足评分标准）评分。结果闭合复位空心螺钉内固定组术后第3天bohler’s 角25．3°～40°（34．8±5．12°）,跟骨高度41～54 mm（47．5±3．94 mm）,术后6个月 bohler’s 角25．4°～39．8°（34．7°±5．15°）,跟骨高度40～54 mm（47．4±5．29 mm）,术后6月 AOFAS 评分优15足,良2足,可1足,优良率94．4％,切开复位钢板内固定组术后3 d bohler’s 角26．3°～39．6°（34．8°±5．24°）,跟骨高度35．5～53．5 mm（47．6±5．25 mm）,术后6个月bohler’s 角26．2°～39．7°（34．7°±5．24°）,跟骨高度35．3～53．4 mm（47．5±5．29 mm）,术后6月 AOFAS 评分优13足,良3足,可2足,优良率88．9％,两组组内比较有统计学差异（P ＜0．05）,组间比较,跟骨高度和 bohler’s 角角度测量结果无统计学差异。结论闭合复位空心螺钉内固定术前 CT 平扫,可以直观的了解跟骨折的具体移位情况,可以更加准确的复位及调整螺钉的布局,符合骨折复位、固定的基本原则,术后关节面塌陷及骨折再移位较切开复位内固定无统计学差异,但减少了切开复位的手术并发症,提高了临床疗效。     

Prognostic Value of Computed Tomography Versus Echocardiography Derived Right to Left Ventricular Diameter Ratio in Acute Pulmonary Embolism

BackgroundComputed Tomography (CT) Pulmonary Angiography is the most commonly used diagnostic study for acute pulmonary embolism (PE). Echocardiogram (ECHO) is also used for risk stratification in acute PE, however the diagnostic performance of CT versus ECHO for risk stratification remains unclear.MethodsCT and ECHO right ventricle (RV) and left ventricle (LV) diameters were measured in a retrospective cohort of patients with acute PE. RV:LV diameter ratios were calculated and correlation between CT and ECHO RV:LV ratio was assessed. Sensitivity and specificity for the composite adverse events endpoint of mortality, respiratory failure requiring intubation, cardiac arrest, or shock requiring vasopressors within 30 days of admission were assessed for CT or ECHO derived RV:LV ratio alone and in combination with biomarkers (troponin or B-type natriuretic peptide).ResultsA total of 74 subjects met the inclusion criteria and had a mean age of 62±18 years. The proportion of patients with RV:LV >1 was similar when comparing CT (37.8%) versus ECHO (33.8%) (P = 0.61). A statistically significant correlation was found between CT derived and ECHO derived RV:LV diameter ratio (r = 0.832, P < 0.001). The sensitivity and specificity to predict 30-day composite adverse events for CT versus ECHO derived RV:LV diameter ratio >1 together with positive biomarker status was similar with sensitivity and specificity of 87% and 41% versus 87% and 42%, respectively.ConclusionsIn patients with acute PE, CT and ECHO RV:LV diameter ratio correlate well and identify similar proportion of PE patients at risk for early adverse events. These findings may streamline risk stratification of patients with acute PE.     

Assessment of the viability and treatment response of bone metastases in patients with metastatic castration-resistant prostate cancer using choline PET/CT

This study aimed to evaluate the clinical use of choline-PET/CT for discriminating viable progressive osteoblastic bone metastasis from benign osteoblastic change induced by the treatment effect and evaluating the response of bone metastasis to treatment in metastatic castration-resistant prostate cancer (mCRPC) patients. Thirty patients with mCRPC underwent a total of 56 ¹¹C-choline-PET/CT scans for restaging, because 4 patients received 1 scan and 26 had 2 scans. Using 2 (pre- and post-treatment) ¹¹C-choline-PET/CT examinations per patient, treatment response was assessed according to European Organization for Research and Treatment of Cancer (EORTC) criteria in 20 situations, in which only bony metastases were observed on ¹¹C-choline-PET/CT scans. Viable bone metastases and osteoblastic change induced by the treatment effect were identified in 53 (94.6%) and 29 (51.8%) of 56 ¹¹C-choline-PET/CT scans, respectively. In 27 cases (48.2%), ¹¹C-choline-PET/CT scans could discriminate the 2 entities. The mean SUVmax of the metastatic bony lesions was 5.82 ± 3.21, 5.95 ± 3.96, 6.73 ± 5.04, and 7.91 ± 3.25 for the osteoblastic, osteolytic, mixed, and invisible types, respectively. Of the 20 situations analyzed, CMR, PMR, SMD, and PMD, as determined by the EORTC, were seen in 1, 2, 3, and 14 cases, respectively. Of the 13 patients with increasing PSA trend, all 13 showed PMD. Of the 2 patients with PSA response of <50%, both 2 showed SMD. Of the 5 patients with PSA response of ≥50%, 1 showed CMR, 2 showed PMR, 1 showed SMD, and 1 showed PMD. Choline-PET/CT is very useful to discriminate viable progressive osteoblastic bone metastasis from osteoblastic change, and assess treatment response of bone metastases in mCRPC.     

Prevalence of abnormal upper limb arterial anatomy and its correlation with access failure during transradial coronary angiography

ObjectiveThe study aimed at to find out prevalence of abnormal upper limb arterial anatomy and its correlation with access failure during transradial coronary angiography.MethodThis was a prospective observational study of 1512 patients who had undergone transradial coronary angiography (CAG). Angiographic assessment of upper limb arterial tree was performed when the angiographic guidewire or the diagnostic catheter followed an abnormal path or got stuck in its course.ResultsAbout 5.29% patients (80/1512) were noted to have abnormal upper limb arterial anatomy. The most common abnormality detected were radio-ulnar loop in 22 (1.46%) patients, tortuous upper limb arteries 19 (1.25%) and abnormal high origin of radial artery 10 (0.66%) patients. Access failure was encountered in 4.4% (67/1512) of total patients and 64.17% (43/67) access failure was due to abnormal upper limb arterial anatomy.ConclusionAbnormal upper limb arterial anatomy was the most common cause of access failure in transradial coronary angiography in this study.     

Distal transradial access for post-CABG coronary and surgical grafts angiography and interventions

BackgroundPost-CABG coronary and grafts angiography (CGAG) and interventions (PCI) have historically been performed via classic transfemoral approach. Particularly for those with left internal mammary artery (LIMA) grafts, left standard transradial access (lsTRA) represents a feasible alternative, with significant fewer vascular complications, but it has ergonomic disadvantage for the operator because of the need to bend over the patients, especially in obese ones. Distal transradial access (dTRA) may provide important advantages, including shorter hemostasis and greater patient and operator comfort, mainly for left dTRA (ldTRA). We aim to describe the feasibility and safety of right and left dTRA for post-CABG CGAG and PCI.Material and methodsFrom February 2019 to April 2021, 111 consecutive post-CABG patients submitted to CGAG and/or PCI via dTRA have been enrolled.ResultsMean patient age was 67.6 years old. Most were male (88.3%) and had chronic coronary syndromes (61.3%). Overall, 35.1% had acute coronary syndromes. Distal RA was successfully punctured in all 111 patients, always without ultrasound guidance. All procedures involving LIMA grafts were done via ipsilateral ldTRA. We had only 5 (4.5%) access site crossovers. Successful dTRA sheath insertion was then achieved in 95.5% of all patients, mostly (74.8%) via ldTRA and with standard 6Fr sheath (99.1%). Distal and proximal RA pulses were palpable in all patients at hospital discharge. No major adverse cardiac and cerebrovascular events and no major complications related to dTRA were recorded.ConclusionsdTRA for routine post-CABG CGAG and PCI by experienced transradial operators appears to be feasible. Further randomized and larger trials are needed to assure clinical benefits and safety of this new technique.