乳腺可疑微钙化灶金属标记夹放置的筛选条件及近期移位的影响因素

目的 探讨乳腺微钙化灶活检过程中放置金属标记夹的筛选条件和影响标记夹移位的因素.方法 108例患者中的114处乳腺微钙化灶做了11 G真空辅助立体定位活检.活检后在每一处病灶都放置了标记央,采用Gel Mark Ultra(82处)或MicroMark Ⅱ标记央(32处).所有钙化簇按照直径和(或)分布被划分成直径<10、10～20、>20 mm的单簇和多簇钙化,并判断金属夹放置的筛选条件.在乳腺X线片上直接测量标记夹和活检部位的距离,按照<10、10～20、>20 mm分成3组.结果 直径<10 mm(25例)和直径10～20 mm之间的单簇钙化(20例)中分别有88.0%(22例)和70.0%(14例)的病灶在活检后显示钙化被取净,直径>20 mm的单簇钙化(17例)没有病灶能被取净.65.8%(75/114)的标记夹准确定位,39个标记夹发生移位,其中34个(87.2%)是沿针道移位,即"手风琴效应"移位.4例患者在活检部位发生大血肿,其中只有1例标记夹能准确定位.结论 直径<20 mm的单簇钙化及多簇钙化灶在活检后都需要放置标记夹,只有直径>20 mm的单簇钙化不需要放置.影响标记夹近期移位的主要因素是"手风琴效应"和血肿.     

Impacted earring clip visible on panoramic radiograph

Earrings are very popular jewelry and ear piercing is performed in very young children. Complications that have been reported in the literature are mainly dermatologic, ranging from embedded foreign body to pressure sores in the post-auricular region. During panoramic radiographic evaluation, precise examination of this area can be used to determine the presence of foreign bodies. In this case, a patient referred to our clinic with panoramic film for an impacted third molar who was not aware of an earring clip impacted in her ear lobe is presented.     

胆囊管打结法腹腔镜胆囊切除的临床研究

 目的探讨腹腔镜腔内打结技术在处理胆囊管胆囊切除术中的效果.方法 600例急慢性结石性胆囊炎和胆囊息肉样病变患者随机分成2组:A组,行打结法处理胆囊管腹腔镜胆囊切除术;B组,行钛夹法处理胆囊管腹腔镜胆囊切除术.比较两组处理胆囊管手术时间、术后平均住院时间、术中出血量、术后并发症及右上腹异物感发生率.结果 A组处理胆囊管手术时间明显延长,与B组比较差异有统计学意义(P＜0.01);但术后平均住院时间、术中出血量、术后并发症发生率差异无统计学意义(P＞0.05);B组右上腹异物感发生例数高于A组.结论无钛夹腔内打结法腹腔镜胆囊切除术具有异物感少,无钛夹留置体内等优点.     

The inferior vena cava clip. The percutaneous approach

Pulmonary embolism in high-risk patients may be minimized by surgical inferior vena cava (IVC) clipping or by the insertion of caval filters. A percutaneous clipping technique was developed that narrows the cava while allowing caval patency. The caval clip is inserted through a percutaneous translumbar approach under fluoroscopic control. Nine dogs underwent percutaneous translumbar caval clip placement without complications. Three of four dogs, followed-up for 5 to 19 weeks by angiography and caval pressure measurements, showed caval patency. This technique eliminates the risks of surgical IVC clip placement and risks from the insertion of intravascular foreign bodies such as filters.     

Minimizing clip artifacts in multi CT angiography of clipped patients

PURPOSE: To optimize the multi CTA (MSCTA) protocol, the influence of pitch, kilovoltage peak (kVp), reconstruction algorithm, type, and orientation of the clip on clip-induced artifacts was investigated in a phantom study. Also, the influence of kVp, concentration of contrast material, and clip orientation in clipped patients was studied. METHODS: A phantom containing a clip was scanned with varying parameters. Artifact was quantified with 3D volumetry. Artifact volumes were compared for the different parameters. In addition, the number of artifact streaks was presented as a function of the pitch. Five clipped patients were scanned with 90 kVp and 120 kVp and 5 with 120 kVp and 140 kVp. The artifact area was compared. The visualization at the clip site was evaluated for different clip orientations in 50 patients, and for 140 kVp with 370 mg iodine/mL contrast (I/mL) compared with 120 kVp/300 mg I/mL in 7 patients. RESULTS: Up to a pitch of 0.6, there was hardly an increase in artifact. Higher kVp and linear interpolation resulted in fewer artifacts. Alloy clips containing cobalt produced more artifact than did titanium clips. Clips positioned perpendicular to the scan plane led to significantly less artifact. In patients with clips, scanning with 140 kVp/370 mgI/mL led to a decrease of artifact area and a better visualization of the clip site. The visualization at the clip site was also better for clips perpendicular to the scan plane. CONCLUSIONS: If clip artifacts are to be minimized, we suggest scanning with a pitch of 0.6, by using 140 kVp and 370 mgI/mL contrast.     

Metallic clip deployment during stereotactic breast biopsy: retrospective analysis

PURPOSE: To determine the visibility of presumably excised lesions on screen-film mammograms obtained after biopsy and to determine the accuracy of clip deployment on the basis of measurements obtained on routine pre- and postbiopsy mammograms. MATERIALS AND METHODS: One hundred eleven cases of core-needle biopsy with clip deployment were reviewed. In each, the type of lesion, lesion location, and biopsy approach were recorded. Pre- and postbiopsy images were reviewed, and the distance between the clip and biopsy site was measured. Postbiopsy images were reviewed to determine whether the targeted lesion remained visible. RESULTS: In 62 (56%) cases, the clip was located within 5 mm of the target on postbiopsy images (craniocaudal and mediolateral), while in 18 (16%), the clip was within 6-10 mm on one projection. However, 31 (28%) clips were more than 1 cm from the target on at least one postbiopsy image. Of the 111 cases, 39 (35%) were malignant or atypical and required excision. Of these, 18 (46%) had clips at least 1 cm from the targeted lesion on at least one projection. CONCLUSION: Metallic clips placed during core-needle breast biopsy are intended to mark the biopsy site when the visible lesion is excised, in case additional biopsy is required. The data suggest that the position of metallic clips placed during stereotactic core-needle biopsy may differ substantially from the location of the biopsy site. Postbiopsy mammography should be performed in two orthogonal planes to document clip position relative to the biopsy site.     

Accuracy of marker clip placement after mammotome breast biopsy.

OBJECTIVE: To assess, after stereotaxic, vacuum-assisted breast biopsy, the accuracy of marker clip deployment for guiding subsequent needle localization procedures and surgery. METHODS: We conducted a retrospective review of 100 vacuum-assisted core breast biopsies that were followed by marker clip deployment. Craniocaudal (CC) and mediolateral oblique (MLO) mammograms were used to locate clips relative to the centre of the target lesion in 5-mm increments. RESULTS: In the 94 of 100 cases adequate for review, maximum marker clip displacement of less than 10 mm on either the CC or MLO views was observed in 68 (72%) cases. In 9 (10%) cases, the localization clip was positioned more that 24 mm from the target lesion. CONCLUSION: Post-biopsy CC and MLO radiographs are recommended to identify those cases in which there is a significant difference between the location of the marker clip and the biopsied lesion.     

Intermediary clip placement to assist accurate axillary lymph node localization

Localization of metastatic axillary lymph nodes in breast cancer patients is an increasingly common procedure performed by radiologists. In 2014, the National Comprehensive Cancer Network guidelines stated that “clinically positive axillary lymph node (s) should be sampled by FNA or core biopsy and clipped with image-detectable marker; clipped lymph nodes must be removed if FNA or core biopsy was positive prior to neoadjuvant therapy”. Since then, multiple studies have further supported targeted axillary surgery after neoadjuvant chemotherapy (NAC), with excision of the clipped metastatic axillary node in addition to the sentinel node (s). Requests for image guided localization of clipped axillary nodes will continue to increase and likely become the standard of care. However, when lymph nodes have decreased in size after NAC, or when small deep lymph nodes are sampled, the clipped node can be difficult to identify under ultrasound at the time of localization. When the target node is questionable, we have found it valuable to place an intermediary clip, and use an axillary mammographic view to confirm this intermediary clip co-localizes with the intended target. With this confirmation, safe, accurate localization can then be performed. We describe 3 cases of intermediary clip placement facilitating successful localization of previously clipped axillary lymph nodes.     

A post-processing algorithm to reduce metallic clip artifacts in CT images

Computed tomography images of cross sections containing metallic implants, such as prosthetic devices or tooth fillings, often have severe artifacts. Such artifacts may hinder medical diagnosis. We present an algorithm to reduce these artifacts. The algorithm involves the convolution back projection and its adjoint, the forward projection. It has two phases — the first phase is a crude correction compensating for beam hardening caused by the metallic objects, and the second a refinement phase. In this second phase, a topological transposition method is introduced in order to replace line integral data going through the metallic objects with the modified corresponding data of a model created from the last image reconstructed in the first phase. A significant improvement in image quality has been observed in both phantom and clinical studies.     

Filshie clip closure: determination of closure through the analysis of X-rays

The Filshie method is a tubal occlusion method commonly used to prevent pregnancy. In medical negligence cases where it is suspected that closure of a Filshie clip may be faulty, lawyers may call on expert surgeons to assess whether or not a clip is closed on the basis of visual examination of the X-rays. However, it is not uncommon for experts to disagree. The aim of this work was to reduce the uncertainty in determining whether or not Filshie clips had been correctly closed. An estimate of the error in the estimate of the clip height was made by propagating measurement errors through a mathematical model. The effects of angle of presentation of the clip, digitisation of the image and resolution of the measurements were studied and the method was applied to two cases. The analysis indicated that measurement errors were least when the digitisation of the image was at 600 dpi, angle of presentation of the clip was less than 40° and the measurements could be made to an accuracy of ±1 pixel. Under these conditions it was possible to determine clip closure height with an error of less than ±0.2 mm.     

Mastectomies after vacuum core biopsy procedure for microcalcification clusters: value of clip

Purpose

The study was performed to substantiate the value of detecting clips in mastectomy specimens as a guide to taking pathological samples.

Material and methods

We performed a retrospective review of 4 cases of mastectomy required after biopsies of microcalcifications. In each case a metallic clip had been inserted at the end of the vacuum core biopsy procedure.

Results

The study included 7 microcalcification clusters with a mean size of 6.7 mm corresponding to multifocal or relapsing ductal carcinoma in situ. Gross examination of the mastectomy specimens revealed no evidence of tumoral lesions or fibrous scar tissue. Radiographic examination of the serial slices did not detect any microcalcifications, but confirmed the presence of the clip in the 7 clusters in 4 cases. Histological examination was performed on the areas identified by the clips and detected scar tissue indicating the location of the biopsies and tumoral lesions in all the specimens.

Conclusion

In the pathological management of mastectomy specimens following vacuum core biopsies, gross examination may reveal no abnormalities and slice radiography may fail to detect microcalcifications. In such cases, radiography of the serial slices allows localisation of the metallic clips inserted during the vacuum-assisted biopsy procedure and remains the only way for the pathologist to select mastectomy specimens for microscopic analysis.     

Reduction of aneurysm clip artifacts on CT angiograms: a technical note.

We describe a head tilt technique for use with CT angiography that reduces beam-hardening artifacts in patients with aneurysm clips. This simple maneuver directs the artifacts away from pertinent anatomy, thus increasing the chances for diagnostic accuracy. No significant changes in the CT angiographic protocol are required, and the maneuver can easily be combined with other artifact-minimizing strategies.