Détection de l’embolie pulmonaire aiguë : apport du scanner X faible dose à la tomoscintigraphie pulmonaire de ventilation et de perfusion

Ventilation and perfusion (V/Q) lung SPECT, performed according to the new recommendations of European Association of Nuclear Medicine (EANM), is a first-line examination for the detection of acute pulmonary embolism. Since low-dose CT scan acquisitions may be recorded during the same examination on hybrid cameras, the corresponding additional information should be assessed. The aim of this study is to compare the diagnostic information provided by lung V/Q SPECT, alone and combined with a low-dose CT scan. Each analysis is performed by two readers; one is more experienced (assistant, A) and one less (interne, I).ResultsThe addition of low-dose CT Scan to lung V/Q SPECT: (1) seldom changes the main diagnostic answer in example the presence or absence of pulmonary embolism (2% for A and 6% for I); (2) frequently gives more minor additional informations, 69% for A and 79% for I (localisation of the involved segments, non embolic pleuroparenchymal abnormalities…) and (3) is associated with a concordance of 87% between the two readers with regard to the final diagnosis of pulmonary embolism (84% for SPECT without CT scan). Seventy-nine percent of these discordances were associated with a low quality of ventilation images.ConclusionWhen added to V/Q lung SPECT, low-dose CT scan commonly provides an additional diagnostic information, without affecting interobserver reproducibility, but this information is generally minor without impact on the diagnosis of pulmonary embolism.     

Scintigraphie pulmonaire pour suspicion d’embolie pulmonaire aiguë : état des lieux des pratiques en France en 2014

AimThe aim of this study was to assess lung scintigraphy practices in France for the diagnosis of acute pulmonary embolism, especially regarding the proportion of centers using single photon emission computed tomography (SPECT) rather than planar ventilation/perfusion (V/Q) imaging.Materials and methodsAn online survey composed of simple multiple-choice questions was distributed to the 210 french nuclear medicine departments in April and May 2014. The survey covered image acquisition, interpretation criteria for SPECT and planar images, and use of pseudoplanar images and radiopharmaceuticals. Departments were initially solicited by 2 sets of e-mails. They were subsequently contacted by phone. A single response per department was consolidated.ResultsTwo hundred nine responses were collected (participation rate: 99.5%). Sixty-seven percent of french centers indicated use of V/Q SPECT in routine practice. The first intention acquisition protocol was SPECT/CT in 34%, SPECT in 26% and V/Q planar in 34%. The most commonly used criteria for SPECT interpretation were those of the EANM (63%). Criteria used for planar interpretation were heterogeneous (EANM criteria, 39%; no standardized criteria, 28%; PIOPED, 23%). Eighty-three percent of centers used ^99mTc aerosol and 17% ^81mKr.ConclusionThis survey shows that SPECT has largely replaced planar imaging for PE diagnosis with lung scintigraphy. Acquisition protocols and interpretation criteria are inconsistent (especially for planar imaging).     

Images pseudoplanaires issues des tomographies pulmonaires : étude de la reproductibilité de lecture et comparaison aux images planaires

PurposeDue to a long time of acquisition, performing during the same examination planar and pulmonary tomography is time expensive. Then, pseudoplanar images have been advocated to be used instead of planar images in the diagnosis of pulmonary embolism. We aim to compare both kinds of images in terms of probability and to assess intra- and inter-observer agreement.Materials and methodsThirty-four patients referred to our unit to diagnose or rule out pulmonary embolism, underwent a planar ventilation/perfusion (V/Q) lung scan and a V/Q lung SPECT. Using the SPECT projections, eight pseudoplanar images were created for each examination. Two experienced physicians read twice both sets of anonymous planar and pseudoplanar images. They checked the probability of pulmonary embolism using the modified PIOPED criteria but without the chest X-ray.ResultsFor both readers, intra-observer agreement for pseudoplanar images is good (κw = 0.69 and 0.78), and similar to the planar images agreement. Interobserver agreement (κw = 0.63) is also good. Both modalities show a good agreement in terms of probability of pulmonary embolism.ConclusionsWe showed that pseudoplanar pulmonary images have a good intra- and interobserver agreement. Furthermore, in our population, these images lead to the same results in terms of probability of pulmonary embolism as those obtained using the standard planar technique.     

Apports de l’acquisition TDM couplée à la scintigraphie pulmonaire dans l’exploration d’une suspicion d’embolie pulmonaire

Pulmonary embolism is a frequent disease difficult to diagnose because of heterogeneous clinical presentation. Pulmonary embolism diagnosis requires additional examinations, which are guided by clinical probability scores. The ventilation/perfusion scintigraphy is a validated technic in pulmonary embolism diagnosis strategies, which represents one of its most important indications. In the past years, the technique of scintigraphy evolved with the appearance of hybrid cameras, allowing the realization of tomoscintigraphy coupled with computerised tomodensitometry (CT). One of the major interests of this technique is the possibility of considering alternative diagnosis in case of negative result of scintigraphy. The purpose of this article is to offer nuclear medicine physicians a review of the alternative diagnoses that can be found during pulmonary ventilation/perfusion tomoscintigraphy according to the underlying scintigraphic and morphological abnormalities. In this review, we will first on diseases responsible for: a mismatch (pathological perfusion and normal ventilation), an inverted mismatch (normal perfusion and pathological ventilation) and for associated disorders in ventilation and in perfusion patterns (identically abnormal perfusion and ventilation). The final part will address some specific CT features that can be encountered on a low dose CT centered on thorax.     

Validité de la somme angulaire comme technique d’extraction d’images planaires à partir de données tomoscintigraphiques pulmonaires de ventilation-perfusion

The aim of our study was to assess the concordance between the results of angular summed images obtained from lung SPECT data versus true planar images in the diagnosis of pulmonary embolism. One hundred and ten patients suspected of pulmonary embolism included in a prospective study underwent a planar lung scan and a lung SPECT. Planar images were extracted from SPECT data using an angular summing technique. Both modalities were reviewed according to revised Pioped criteria by two nuclear medicine physicians. Concordance between modalities and observers was compared with a weighted kappa test. A good degree of agreement between the two modalities (κ = 0.696) were found. Interobserver degree of agreement was similar in planar images (κ = 0.919) and in angular summed images (κ = 0.903). These results suggest that angular sum images from SPECT data are usable and concordant with ventilation perfusion planar images.     

Imagerie hybride dans l’embolie pulmonaire aiguë : apport de la TDM couplée à la tomoscintigraphie de ventilation et de perfusion

Purpose

V/P-SPECT lung scan can be combined with computerized tomography (CT) from hybrid camera. We investigated if CT data could be use only with perfusion scans for the diagnosis of acute pulmonary embolism (PE).

Patients and methods

In a retrospective study, 75 consecutives patients, referred for suspicion of PE, underwent SPECT ventilation and perfusion scans coupled with a CT on Symbia T2. The perfusion images (P-SPECT) were classified as normal or abnormal with systematized (segmental and sub-segmental) or not systematized perfusion abnormalities. The ventilation images (V-SPECT) were considered as normal or abnormal in light of perfusion defects. The same was done for CT images. Correlations between V-SPECT and CT were studied.

Results

Hence, 28 patients had a normal P-SPECT and did not have PE. Patients (47) had an abnormal P-SPECT (among them, 16 turned out to have PE and 31 did not). There were 192 perfusion abnormalities of which 81 were segmental and 81 sub-segmental. Corresponding to these abnormalities, V-SPECT and CT were concordant in 83 % of the cases. When not-concordant, V-SPECT abnormalities with normal CT were found in 14 % of the cases and CT abnormalities with normal V-SPECT were found in 3 % of the cases. According to the EANM guidelines for PE diagnosis, sensitivity was 88 % and specificity 93 % with V/P-SPECT and 100 % and 83 % respectively with CT/P-SPECT (p = NS).

Conclusion

V/P-SPECT remains slightly more specific for the diagnosis of PE. However, this study demonstrates that CT/P-SPECT obtained with hybrid camera could be used for PE diagnosis with performances similar to V/P-SPECT. If these results would be confirmed on larger populations, this could lead to a significant reduction of scanning time which would improve patient comfort and reduce the camera load.     

43例术后疑似急性肺栓塞分析

目的:探讨影响术后急性肺栓塞(Acute Pulmonary Embolism,APE)的发生和预后的相关因素,以提高对术后肺栓塞的认识和诊疗水平。方法:收集2009.01-2014.12期间南方医院术后疑似急性肺栓塞患者的临床资料,总结其临床特征,分析其诱发因素、临床表现、治疗和预后,探讨其发病的高危因素。结果:共收集术后疑似肺栓塞43例,平均年龄56.09±14.08岁(17~80岁),明确诊断为肺栓塞15例(34.9%),共死亡20例(死亡率46.5%)。其临床表现和体征均具有非特异性,呼吸困难、心悸和晕厥是主要的临床表现。不仅可以发生于下肢、胸腹部(包括妇产科)、颅内等大手术后,也可能发生在介入栓塞术后。相关危险因素很多,包括性别、年龄、恶性肿瘤、全身麻醉、手术时间长等。具有高危因素的患者并具有可疑肺栓塞的临床表现时,结合D-二聚体、动脉血气分析、心电图、胸部X线、超声心动图、下肢彩超可检查协助APE的诊断,而胸部增强CT作为检查手段有利于明确诊断。结论:肺栓塞是手术后致命的并发症之一,早期诊断、早期治疗,能降低术后肺栓塞患者的死亡率。     

La perfusion pulmonaire en morphoTEMP dans le diagnostic de l’embolie pulmonaire : comparaison à la scintigraphie pulmonaire planaire de ventilation/perfusion

The aim of this study is to assess a new tool for the diagnosis of acute pulmonary embolism (PE): single-photon emission computed tomography lung perfusion imaging associated with unenhanced computed tomography (SPECT/CT) compared to planar ventilation-perfusion (VQ) lung scintigraphy.MethodsOne hundred and three patients with suspected acute PE underwent VQ scintigraphy (two scans were uninterpretable) followed by perfusion SPECT/CT. The two types of images were analysed separately: (1) according to the modified PIOPED scintigraphic criteria for VQ lung scan and (2) with regard to SPECT/CT mismatches suggestive acute PE (segmental perfusion defects detected on SPECT images not matched with CT abnormalities).ResultsOn average, the number of segmental perfusion defects per patient was higher with SPECT/CT than with planar scintigraphy (4.3 ± 3.6 versus 2.8 ± 2.6; p < 0.001). A mismatch was found with SPECT-CT in 0% (0/18) of normal scintigraphy, and 8% (3/39) for low, 32% (8/25) for intermediate and 74% (14/19) for high probabilities of PE at scintigraphy. The presence of a SPECT/CT mismatch was also associated with higher pretest probability of acute PE (p = 0.001), even for the 25 patients in the intermediate-probability subgroup (p = 0.02). Finally, a SPECT/CT match was found in 29 patients that was not suggestive of acute PE due to the presence, in areas with perfusion defects on SPECT images, of the following CT abnormalities: hypodensity and/or emphysema (71%), condensation or atelectasis (38%), pleural disease (7%), extrapulmonary structure (14%) and/or bronchial obstruction (7%).ConclusionIn patients with suspected acute PE, the results obtained with pulmonary SPECT/CT images are consistent with those obtained with VQ scintigraphy and the pretest probability of PE. Further studies comparing SPECT/CT imaging with angiographic techniques are now required to evaluate more specifically the diagnostic value of this new tool.     

Scintigraphie des parathyroïdes double isotope Tc-MIBI/I dans l’hyperparathyroïdisme primaire : comparaison entre un protocole d’acquisition planaire et une TEMP de soustraction couplée à la TDM

In patient with primary hyperparathyroidism, preoperative imaging first objective is to determine accurately and reliably position and anatomic localization of enlarged parathyroid gland in order to guide surgeon for gland removal and to permit minimally invasive surgery. Although subtraction planar scintigraphy is an efficient imaging to diagnose hyperfunctioning parathyroid, the lack of anatomical reference for this single imaging technique could be obviated by hybrid imaging. We compared, in 23 patients with primary hyperparathyroidism, a planar scan of neck and mediastinum associated with a cervical anterior pinhole scan to a subtraction (¹²³I/^99mTc-MIBI) SPECT scan of neck and mediastinum fused with CT. Surgical and histopathologic findings were used as the standard of truth. Subtraction SPECT/CT appeared to be more sensitive and specific than planar protocol to diagnose and to accurately localize pathologic parathyroid. Sensitivity was 76 and 56 %, specificity was 100 and 80 % for hybrid SPECT/CT and planar protocol respectively. SPECT protocol was typically more efficient to diagnose pathologic parathyroid derived from upper gland and for patient with concomitant nodular goiter.     

The low specificity of postoperative perfusion lung scan defects.

Ventilation and perfusion lung scans were performed preoperatively and postoperatively in 169 patients and classified blindly according to preset criteria. Perfusion lung scan abnormalities were present in 25 (15%) of the preoperative scans and 42 (25%) of the postoperative scans; 16 (38%) of the 42 abnormal postoperative scans were identical to the preoperative scans. Perfusion defects indicating a "high probability" of pulmonary embolism (lobar or segmental defects) were present in 5 preoperative scans and 10 postoperative scans; the 10 postoperative scans were classified as showing "definite" (5), "possible" (1) or "no" (4) pulmonary embolism on the basis of the preoperative scan and the ventilation scan; none of the 10 patients had clinical evidence of pulmonary embolism. Venous thrombosis was present in 12 patients, including 4 of the patients whose lung scans showed definite pulmonary embolism. Thus, postoperative perfusion lung scan defects are potentially misleading even when large.     

Physiological imaging of the lung: single-photon-emission computed tomography (SPECT).

Emission tomography provides three-dimensional, quantitative images of the distribution of radiotracers used to mark physiological, metabolic, or pathological processes. Quantitative single photon emission computed tomography (SPECT) requires correction for the image-degrading effects due to photon attenuation and scatter. Phantom experiments have shown that radioactive concentrations can be assessed within some percentage of the true value when relevant corrections are applied. SPECT is widely spread, and radiotracers are available that are easy to use and comparably inexpensive. Compared with other methods, SPECT suffers from a lower spatial resolution, and the time required for image acquisition is longer than for some alternative methods. In contrast to some other methods, SPECT allows simultaneous imaging of more than one process, e.g., both regional blood flow and ventilation, for the whole lung. SPECT has been used to explore the influence of posture and clinical interventions on the spatial distribution of lung blood flow and ventilation. Lung blood flow is typically imaged using macroaggregates of albumin. Both radioactive gases and particulate aerosols labeled with radioactivity have been used for imaging of regional ventilation. However, all radiotracers are not equally suited for quantitative measurements; all have specific advantages and limitations. With SPECT, both blood flow and ventilation can be marked with radiotracers that remain fixed in the lung tissue, which allows tracer administration during conditions different from those at image registration. All SPECT methods have specific features that result from the used radiotracer, the manner in which it is administered, and how images are registered and analyzed.     

Imaging Non-Specific Wrist Pain: Interobserver Agreement and Diagnostic Accuracy of SPECT/CT,MRI, CT,Bone Scan and Plain Radiographs

Purpose

Chronic hand and wrist pain is a common clinical issue for orthopaedic surgeons and rheumatologists. The purpose of this study was 1. To analyze the interobserver agreement of SPECT/CT, MRI, CT, bone scan and plain radiographs in patients with non-specific pain of the hand and wrist, and 2. to assess the diagnostic accuracy of these imaging methods in this selected patient population.

Materials and Methods

Thirty-two consecutive patients with non-specific pain of the hand or wrist were evaluated retrospectively. All patients had been imaged by plain radiographs, planar early-phase imaging (bone scan), late-phase imaging (SPECT/CT including bone scan and CT), and MRI. Two experienced and two inexperienced readers analyzed the images with a standardized read-out protocol. Reading criteria were lesion detection and localisation, type and etiology of the underlying pathology. Diagnostic accuracy and interobserver agreement were determined for all readers and imaging modalities.

Results

The most accurate modality for experienced readers was SPECT/CT (accuracy 77%), followed by MRI (56%). The best performing, though little accurate modality for inexperienced readers was also SPECT/CT (44%), followed by MRI and bone scan (38% each). The interobserver agreement of experienced readers was generally high in SPECT/CT concerning lesion detection (kappa 0.93, MRI 0.72), localisation (kappa 0.91, MRI 0.75) and etiology (kappa 0.85, MRI 0.74), while MRI yielded better results on typification of lesions (kappa 0.75, SPECT/CT 0.69). There was poor agreement between experienced and inexperienced readers in SPECT/CT and MRI.

Conclusions

SPECT/CT proved to be the most helpful imaging modality in patients with non-specific wrist pain. The method was found reliable, providing high interobserver agreement, being outperformed by MRI only concerning the typification of lesions. We believe it is beneficial to integrate SPECT/CT into the diagnostic imaging algorithm of chronic wrist pain.     

肺动脉栓塞的64层螺旋CT血管成像技术分析

目的从技术上探讨64层螺旋CT肺动脉造影对肺栓塞的诊断的价值。方法对62例临床疑诊肺栓塞的患者行64排螺旋CT肺动脉造影检查,采用最大密度投影(MIP)、多平面重建(MPR)、曲面重建(CPR)、容积漫游(VR)及仿真内窥镜等后处理技术,分析所获得的相关CT资料。结果64排多层螺旋CT肺动脉造影可较准确、清晰、全面地显示24例累及肺动脉及其分支共152处栓子的位置、形态、范围和程度。结论64排多层螺旋CT肺动脉造影是肺栓塞及时准确无创的诊断方法,是临床诊断肺栓塞的首选筛查办法,对肺动脉栓塞的诊断具有明显的技术优势。     

Place de la scintigraphie dans le diagnostic de l’embolie pulmonaire chez la femme enceinte – À propos de 17 cas

IntroductionPulmonary embolism in pregnant women is a deadly disease; its diagnosis is based on specific algorithms. The lung scan is one of the recommended diagnostic suspicion in further investigations.Material and methodsRetrospective study of a series of cases of pulmonary embolism in the period pre-partum and post-partum pregnant women collected during 3 years, from January 2010 to January 2013, at the reanimation department maternity Souissi in Rabat.ResultsSeventeen cases of pulmonary embolism pre- and post-partum. The age ranged between 21 and 37 years (mean age 30 years). Four EP post-partum were recorded with 13 cases of EP pre-partum whose mean gestational age was 30SA. Several risk factors were found: 7 cases obesity, 4 cases cesarean section, 3 cases of varicose veins, 2 cases of endometritis, 1 case of twin pregnancy, 1 case of gestational hypertension and 1 case of alitement. The first reason for consultation was respiratory distress (12 cases), followed by chest pain (9 cas) and palpitations (6 cas). Lung scintigraphy performed in 14 patients’ objective 9 cases of perfusion defect, 4 cases of normal scan and 1 case of massive PE. No deaths or recurrences have been reported.ConclusionPregnancy and the post-partum period are at high risk of thromboembolic events due to physiological changes. The diagnostic approach is now well codified with scores of clinical and paraclinical probability. The lung scintigraphy can be a method of choice. Hybrid imaging is a good alternative for diagnostic performance.     

Apports de l’imagerie hybride TEMP/TDM dans le descellement aseptique de prothèse de hanche

Hip prosthesis loosening detection is a common indication for bone scan, however, the diagnosis can be difficult to confirm based solely on bone scan information which have a low specificity. The development of bone SPECT/CT hybrid imaging allows the correlation of two complementary modalities to palliate the low sensitivity of CT caused by metallic artefacts and the moderate specificity of bone scan. It becomes a necessity for nuclear medicine physicians to master the bases of pathological hip prosthesis radiological semiology. We propose in this review article to recall the physiopathology of prosthesis loosening then we will describe the radiological and scintigraphic characteristics of hip prosthesis loosening as well as its differential diagnoses and the benefits of other imaging modalities.     

Thromboses néoplasiques et thromboses cruoriques mécaniques compliquant un cancer du testicule gauche en TEP/TDM au 18FDG

We report the case of a 46-year-old patient with pulmonary embolism complicating thrombosis of the left renal vein and inferior vena cava, which came from a malignant tumor of the left testicle. The case has been elucidated by positron emission tomography with ¹⁸FDG coupled to the CT-scan (PET/CT), performed as part of the etiological assessment of this pulmonary embolism, and anatomical and physiological considerations. The examination revealed ¹⁸FDG uptake in thrombus of the left kidney vein and the inferior vena cava. In view of the anatomy of the left spermatic vein, this finding led to the left testicle, which shows no nuclide uptake but was bathed in a large hydrocele visible on CT images. If several cases of pulmonary embolism or thrombosis of the inferior vena cava revealing a testicular cancer have been described in the literature, there has been no report including ¹⁸FDG PET/CT to the best of our knowledge. This case illustrates the imaging differences between bland and malignant thrombus as a consequence of their pathophysiology. It highlights the contribution of CT images from the PET/CT for the diagnosis.     

Reproductibilité en scintigraphie osseuse planaire,TEMP et TEMP/TDM du pied douloureux : importance d’une sémiologie standardisée

AimThe diagnostic benefit of bone single photon emission computed tomography/computed tomography (SPECT/CT) is currently being demonstrated. However, until now, reproducibility has been poorly investigated. Therefore, a study was undertaken to assess intra- and inter-reader reliability comparing bone planar views, SPECT and SPECT/CT.MethodsThe study was carried out on a cohort of 50 adults consecutively referred to two distinct Nuclear Medicine departments for clinical and radiological suspicion of a reflex sympathetic dystrophy (RSD) of the foot. Each set of planar views and SPECT/CT was independently re-read by two Nuclear Medicine physicians (one junior and one senior expert) in a blinded fashion. An array of bone scan and CT semiological criteria depicting RSD and main differential diagnoses was initially elaborated. Reliability was measured by percentage of agreement and computation of unweighted kappa.ResultsAmong the 50 patients, only four actually suffered from RSD. Among the 46 patients who did not suffer from RSD, 28 were affected by miscellaneous skeletal lesions. This is the reason why the study shifted from focusing on RSD to the etiologic diagnosis of a painful foot. Percentage of inter-reader agreement rose from 74% for planar scintigraphy and SPECT to 96% for SPECT/CT. This study showed reliability indices higher than in literature mainly due to the use of predefined detailed semiological criteria and to the learning effect of the junior physician at senior physician school.ConclusionBone SPECT/CT provides significantly stronger intra-reader and inter-reader agreement in comparison to planar images and stand-alone SPECT.     

128层螺旋CT肺动脉造影对急性肺栓塞患者栓塞程度和右心功能的评估价值研究

目的:探讨128层螺旋CT肺动脉造影(CTPA)对急性肺栓塞(APE)患者栓塞程度和右心功能的评估价值。方法:选取2016年7月到2018年6月期间在我院行CTPA检查确诊并接受治疗的APE患者100例记为观察组,根据观察组患者的病情将其分为高危组(57例)和非高危组(43例),同时根据观察组患者肺栓塞部位及预后将患者分为中心肺栓塞死亡组(8例)、中心肺栓塞存活组(38例)、周围肺栓塞组(54例)。另选择同期于我院进行CTPA检查的无肺栓塞患者50例记为对照组。记录所有患者的右心功能参数[右心室短轴最大径(RVMSA)、左心室短轴最大径(LVMSA)以及二者的比值(RV:LV)],计算APE患者的CT肺动脉阻塞指数,并分析APE患者CT肺动脉阻塞指数与右心功能指标的相关性。结果:观察组的RVMSA、RV:LV均明显高于对照组(P0.05),高危组的CT肺动脉阻塞指数、RVMSA、RV:LV均明显高于非高危组(P0.05)。中心肺栓塞死亡组的CT肺动脉阻塞指数、RVMSA、RV:LV均明显高于中心肺栓塞存活组和周围肺栓塞组,中心肺栓塞存活组的CT肺动脉阻塞指数、RVMSA、RV:LV均明显高于周围肺栓塞组(P0.05)。经Pearson相关分析显示,APE患者CT肺动脉阻塞指数与RVMSA、RV:LV均呈正相关(P0.05),与LVMSA无明显的相关性(P0.05)。结论:CTPA检查可有效评估APE患者的栓塞程度和右心功能,且栓塞程度与右心功能存在相关性,CTPA检查有助于APE患者的诊断和病情评估。     

Geneva量表在肺栓塞诊断中的意义

随着认识水平的提高,已发现肺栓塞是临床很常见的疾病。对于如何更好地进行肺栓塞危险性的评估和组织相对复杂的检查,Geneva量表将是临床非常实用的工具。Geneva量表更精确和稳定,较少受临床经验的影响。对于合并慢性阻塞性肺病的患者诊断也有意义。同时,对于预测肺栓塞后3月内不良事件也有价值,临床试验证实对CT检查阴性患者Geneva量表评分为低中度危险不进行抗凝治疗也是安全的。本文将对目前国际上对Geneva量表的应用进展做一综述。     

Apport de l’imagerie hybride TEMP/TDM dans la détection des ganglions sentinelles : à propos de 32 cas

Objectives

Retrospective evaluation of the SPECT/CT role in the Sentinel Lymph Node identification.

Patients and methods

Thirty-two patients underwent a lymphoscintigraphy with SPECT/CT imaging. Those patients presented several cancer types (16 melanoma, one squamous cell carcinoma, three breast cancers, eight vulvar cancers, three cervical cancers).

Results

The scintigraphic detection rate was 81% with planar imaging while this rate was 89% with SPECT/CT. The SPECT/CT provided an additional quantitative information in 66% cases. Moreover, the quality of the interpretation was better in two different conditions (planar interpretation followed by routine and blinded SPECT/CT interpretation) with SPECT/CT. In our study, the false negative rate is 4.5%.

Conclusions

SPECT/CT provides quantitative and qualitative informations in the sentinel lymph node detection. Therefore, it can be a valuable tool for the surgeon to find and harvest the sentinel lymph node especially where the lymphatic drainage pattern can be unusual or hard to predict (cervical or trunk localisation). It's a new tool for preoperative detection and it can decrease the false negative rate.