Real-time Lesion Research Articles

Reproducibility and diagnostic performance of the vascular index of superb microvascular imaging in real-time breast ultrasonography for evaluating breast masses.

PurposeThis study aimed to evaluate the reproducibility and diagnostic performance of a quantitative parameter of superb microvascular imaging (SMI) in real-time breast ultrasonography (US) for differentiating benign from malignant breast masses.MethodsEighty-seven breast masses in 75 patients who underwent both B-mode US and SMI before US-guided core needle biopsy were included in this study. Two radiologists performed B-mode US and measured the vascular index (VI) of SMI respectively for each lesion in real time. Intraobserver and interobserver agreements were analyzed for the VI of SMI. The diagnostic performance of B-mode US using the Breast Imaging Reporting and Database System lexicon and combined use with the VI of SMI was evaluated compared to pathology.ResultsThe median VI of malignant masses (n=32) was significantly higher than that of benign masses (n=55) (7.6% and 2.6%, respectively; P<0.001). The intraobserver agreement for VI was excellent regardless of the pathology, size, or depth of the lesion. The interobserver agreement for VI was excellent regardless of the presence of a measurement interval. The interobserver agreement for the final diagnostic decision was improved by combining B-mode US and VI (κ=0.883) in comparison with B-mode US only (κ=0.617). Adding VI led to significant improvements in the specificity (87.2% vs. 52.7%, 83.6% vs. 49.0%), accuracy (89.7% vs. 69.3%, 84.0% vs. 65.9%) and positive predictive value (81.5% vs. 55.1%, 75.6% vs. 52.6%) of B-mode US for both observers compared with B-mode US alone (all, P=0.001).ConclusionThe VI of SMI for real-time breast US is highly reproducible and leads to improved diagnostic performance for differentiating between benign and malignant breast lesions in combination with B-mode US.

Dual modal fluorescent colposcope combined with near-infrared fluorescent dye TMTP1-PEG4-ICG to detect cervical lesions.

To examine the cervical lesions by using the tumor-targeted near-infrared (NIR) fluorescent dyes TMTP1-PEG4-ICG, a dual modal colposcope with visible reflectance imaging and fluorescence imaging was developed. NIR fluorescence imaging and visible light reflectance imaging were integrated together on a colposcope by designing the specific optics and adopting a dual sensor charge coupled device (CCD) camera. Patients with squamous cell carcinoma, adenocarcinoma, cervical intraepithelial neoplasia (CIN) and cervicitis were examined using this dual modal colposcope to validate its potential of cervical cancer detection. Fluorescent dye TMTP1-PEG4-ICG was applied to the cervix 30 minutes before inspection. The fluorescence images were collected after wiping the unbound fluorescent dye using normal saline. Signal to back ratios (SBR) of the fluorescence images were analyzed and compared with the histological analysis. The results suggest that the fluorescent colposcope combined with tumor-specific near-infrared fluorescent dyes TMTP1-PEG4-ICG could help to evaluate cervical lesions in real time.

Identification of tea foliar diseases and pest damage under practical field conditions using a convolutional neural network

AbstractLesions of tea (Camellia sinensis) leaves are detrimental to the growth of tea crops. Their adverse effects include further disease of tea leaves and a direct reduction in yield and profit. Therefore, early detection and on‐site monitoring of tea leaf lesions are necessary for effective management to control infections and prevent further yield loss. In this study, 1,822 images of tea leaves with lesions caused by three diseases (brown blight, Colletotrichum camelliae; blister blight, Exobasidium vexans; and algal leaf spot, Cephaleuros virescens) and four pests (leaf miner, Tropicomyia theae; tea thrip, Scirtothrips dorsalis; tea leaf roller, Homona magnanima; and tea mosquito bug, Helopeltis fasciaticollis) were collected from northern and central Taiwan. A faster region‐based convolutional neural network (Faster R‐CNN) was then trained to detect the locations of the lesions on the leaves and to identify the causes of the lesions. The trained Faster R‐CNN detector achieved a precision of 77.5%, recall of 70.6%, an F1 score of 73.91%, and a mean average precision of 66.02%. An overall accuracy of 89.4% was obtained for identification of the seven classes of tea diseases and pests. The developed detector could assist tea farmers in identifying the causes of lesions in real time.

Optical surgical navigation-assisted removal of a foreign body using a splint to simplify the registration process: a case report

BackgroundOral and maxillofacial surgeons often encounter foreign objects within the human body. Despite the visual identification of foreign objects via imaging techniques, the accurate determination of their position in the maxillofacial area can be challenging. The clinical application of a navigation system can solve this issue. This system provides a useful guide for a safer and more accurate surgical technique by accurately determining the location of the lesion in real time during the surgery. However, complications with regard to registration may be encountered. We describe a navigation system that simplifies registration using a dental splint with embedded reference points for foreign body removal in the maxilla.Case presentationA 78-year-old Japanese woman was referred with the chief complaint of pain in the left upper molar region. We found the symptoms to be associated with a foreign body in the maxilla and decided to remove it. A minimally invasive treatment procedure was desirable. However, the lesion was in contact with the maxillary sinus, and it was difficult to pinpoint its position because of the absence of an anatomical landmark. Therefore, we decided to use a navigation system. In order to simplify registration, a dental splint with embedded reference points was created. The registration could be reliably performed before surgery using an optical navigation system that facilitates the process, using splints with embedded reference points. Following preoperative registration, the splint with the reference frame was placed in the patient’s mouth, and the accuracy of the navigation was confirmed. The position with respect to the maxillary sinus was precisely identified followed by the removal of the surrounding bone and excision of the lesion. Therefore, the surgery could be accurately performed without perforating the maxillary sinus. In addition, owing to preoperative registration, the operative time could be shortened. After the surgical procedure, the patient’s symptoms disappeared.ConclusionsThe procedure was performed in a precise, minimally invasive manner. Furthermore, the operative time was reduced by the simplified registration process, wherein a splint was embedded with reference points. This technique may prove useful for performing maxillofacial surgical procedures.

Noninvasive Monitoring of Lesion Size in a Heterologous Mouse Model of Endometriosis.

Here, we describe a protocol for the implementation of a heterologous mouse model in which progression of endometriosis can be assessed in real time through noninvasive monitoring of fluorescence emitted by implanted ectopic human endometrial tissue. For this purpose, biopsies of human endometrium are obtained from donor women ongoing oocyte donation. Human endometrial fragments are cultured in the presence of adenoviruses engineered to express cDNA for the reporter fluorescent protein mCherry. Upon visualization, labeled tissues with an optimal rate of fluorescence after infection are subsequently chosen for the implantation in recipient mice. One week prior to the implantation surgery, recipient mice are oophorectomized, and estradiol pellets are placed subcutaneously to sustain the survival and growth of lesions. On the day of surgery mice are anesthetized, and peritoneal cavity accessed through a small (1.5 cm) incision by the linea-alba. Fluorescently labeled implants are tweezed, briefly soaked in glue and attached to the peritoneal layer. Incisions are sutured, and animals left to recover for a couple of days. Fluorescence emitted by endometriotic implants is usually non-invasively monitored every 3 days for 4 weeks with an in vivo imaging system. Variations in the size of endometriotic implants can be estimated in real time by quantification of the mCherry signal and normalization against the initial time-point showing maximal fluorescence intensity. Traditional preclinical rodents of models of endometriosis do not allow non-invasive monitoring of lesion in real time but rather allow evaluation of the effects of drugs assayed at the end point. This protocol allows one to track lesions in real time and is more useful to explore the therapeutic potential of drugs in preclinical models of endometriosis. The main limitation of the model thus generated is that non-invasive monitoring is not possible over long periods of time due to the episomal expression of Ad-virus.

Diagnostic Accuracy of Reflectance Confocal Microscopy for Diagnosis of Skin Lesions: An Update.

Histopathology is the current standard to diagnose skin disease. However, biopsy may not always be feasible, such as in patients with multiple nevi, a patient with a lesion on an aesthetically significant site, or in children. Recently, noninvasive techniques, including reflectance confocal microscopy (RCM), optical coherence tomography, and Raman spectroscopy, have enabled dermatologists to manage skin lesions in real time without the need for biopsy. To report the updated diagnostic accuracy of RCM for equivocal skin lesions. In this study, we retrospectively reviewed our data of clinically suspicious lesions from 2010 to 2017 that were evaluated by RCM. Our results showed an overall sensitivity of 98.2% and specificity of 99.8%. In conclusion, RCM is a noninvasive real-time tool with the potential to diagnose skin lesions with high accuracy and without biopsy.

Diagnostic yield of electromagnetic navigational bronchoscopy: results of initial 35 cases in a Japanese institute.

Electromagnetic navigational bronchoscopy (ENB) is a new bronchoscopic technique for navigational transbronchial lung biopsy (TBLB) that guides the sheath to the target lesion in real time. Herein, we report our experience with this navigational system, its diagnostic yields, and associated complications. A single-center, single-operator retrospective chart review was performed. We included 35 consecutive patients who underwent ENB with superDimensionTM (Medtronic, MN, USA) for the diagnosis of pulmonary lesions from February 2016 to May 2017 in Kyoto University Hospital. The size of the target lesion varied from 8 to 25 mm (median, 15.28±5.48 mm). All ENB procedures were performed under conscious sedation using 2 to 10 mg midazolam and 1 to 10 mg morphine hydrochloride. No fluoroscopic guide was employed except in three cases. A total of 25 patients were diagnosed via ENB, yielding a diagnostic rate of 71.4% (25/35). The average lesion size of the diagnosed group was 16.44±5.44 mm (range, 8-25 mm). Eighteen cases were diagnosed as primary lung cancer, 3 were metastatic lung cancer, and 4 were inflammatory diseases. The average lesion size of the 10 undiagnosed cases was 12.40±5.21 mm (range, 8-24 mm). The lesion size of the undiagnosed group was significantly smaller than that of the diagnosed group (P=0.02). The average time required for the procedure was 16.78±9.57 minutes (range, 3-46 minutes), independent of the diagnosis, the lesion size, and the tumor location. We encountered one pneumothorax which required chest drainage and one hemopneumothorax which required non-elective thoracotomy and wedge resection. One patient developed high fever over 38 °C for one day following the procedure. In our initial series of 35 cases, ENB-guided TBLB showed an acceptable diagnostic yield.

Finding Small-Bowel Lesions: Challenges in Endoscopy-Image-Based Learning Systems

Capsule endoscopy identifies damaged areas in a patient’s small intestine but often outputs poor-quality images or misses lesions, leading to either misdiagnosis or repetition of the lengthy procedure. The authors propose applying deep-learning models to automatically process the captured images and identify lesions in real time, enabling the capsule to take additional images of a specific location, adjust its focus level, or improve image quality. The authors also describe the technical challenges in realizing a viable automated capsule-endoscopy system.

CEUS-Diagnostic of malignant liver lesions

Cross-sectional modalities or conventional ultrasound are not always able to sufficiently identify and characterize malignant liver lesions. The evaluation of malignant liver lesions in conventional ultrasound relies on echostructure, shape and borders, but often warrants additional contrast-enhanced computed tomography (CT) or magnetic resonance imaging (MRI) studies. Contrast-enhanced ultrasound (CEUS) is arelatively safe imaging technique used for the detection and characterization of malignant liver lesions. The use of asecond-generation contrast agent in dynamic real-time imaging allows the visualization of vascularization in any kind of liver lesion as well as liver perfusion during the arterial, portal venous and late phase. Due to the different enhancement patterns, it is possible to differentiate aliver lesion with high diagnostic accuracy (over 90%). CEUS is ahelpful complementary technique to cross-sectional imaging for the evaluation of unclear liver lesions and may frequently obviate additional contrast-enhanced MRI or CT studies. CEUS enables the detection and characterization of liver lesions in real time.

CEUS-diagnosis of benign liver lesions

Focal liver lesions are commonly seen during routine ultrasound examinations. With native ultrasound there are lesions that cannot be sufficiently characterized. In these cases additional imaging might be necessary. With contrast-enhanced ultrasound (CEUS), focal liver lesions can be characterized with high diagnostic accuracy. After the ultrasound contrast agent has been injected into aperipheral vein, the examiner saves video loops of the arterial, portal venous and late contrast phases. Combing the findings of native and contrast-enhanced ultrasound allows not only assessment of the etiology as benign or malignant but also detailed characterization of the focal liver lesion in most cases. Using CEUS, focal liver lesions can be characterized with asensitivity of over 95% and aspecificity of about 83%. The advantages of CEUS include that there is no radiation exposure and that the ultrasound contrast agent has no effects on the function of the liver, kidneys or the thyroid gland. The main limiting factors for CEUS are bowel gas and obesity of the patient. CEUS can visualize micro- and macrovascularization of benign focal liver lesions in real time. It is auseful imaging modality in unclear cases.

Smart connected electronic gastroscope system for gastric cancer screening using multi-column convolutional neural networks

Gastroscopy is a widely adopted method for gastric cancer screening and early diagnosis. Clinical studies show that it can effectively prolong patient life and maximise therapeutic effect. However, it is difficult for doctors to identify and detect lesions in real time, which manifests as the major challenge in gastroscopy. In this paper, we propose SCEG, a smart connected electronic gastroscopy system that performs dynamic cancer screening in gastroscopy. By integrating electronic gastroscopy with cloud-based medical image analysis service, we develop an AdaBoost-based multi-column convolutional neural network (MCNN) for enhancing gastric cancer screening. Experimental results show that the proposed MCNN approach significantly outperforms other competing approaches.

Technical Note: On Cardiac Ablation Lesion Visualization for Image-guided Therapy Monitoring.

The delivery of insufficient thermal dose is a significant contributor to incomplete tissue ablation and leads to arrhythmia recurrence and a large number of patients requiring repeat procedures. In concert with ongoing research efforts aimed at better characterizing the RF energy delivery, here we propose a method that entails modeling and visualization of the lesions in real time. The described image-based ablation model relies on classical heat transfer principles to estimate tissue temperature in response to the ablation parameters, tissue properties, and duration. The ablation lesion quality, geometry, and overall progression is quantified on a voxel-by-voxel basis according to each voxel's cumulative temperature and time exposure. The model was evaluated both numerically under different parameter conditions, as well as experimentally, using ex vivo bovine tissue samples. This study suggests that the proposed technique provides reasonably accurate and sufficiently fast visualizations of the delivered ablation lesions.

Cardiac Lesion Mapping In Vivo Using Intracardiac Myocardial Elastography.

Radio frequency (RF) ablation of the myocardium is used to treat various cardiac arrhythmias. The size, spacing, and transmurality of lesions have been shown to affect the success of the ablation procedure; however, there is currently no method to directly image the size and formation of ablation lesions in real time. Intracardiac myocardial elastography (ME) has been previously used to image the decrease in cardiac strain during systole in the ablated region as a result of the lesion formation. However, the feasibility of imaging multiple lesions and identifying the presence of gaps between lesions has not yet been investigated. In this paper, RF ablation lesions ( ) were generated in the left ventricular epicardium in three anesthetized canines. Two sets of two lesions each were created in close proximity to one another with small gaps (1.5 and 4 cm), while one set of two lesions was created directly next to each other with no gap. A clinical intracardiac echocardiography system was programmed to transmit a custom diverging beam sequence at 600 Hz and used to image the ablation site before and after the induction of ablation lesions. Cumulative strains were estimated over systole using a normalized cross-correlational displacement algorithm and a least-squares strain kernel. Afterward, lesions were excised and subjected to tetrazolium chloride staining. Results indicate that intracardiac ME was capable of imaging the reduction in systolic strain associated with the formation of an ablation lesion. Furthermore, lesion sets containing gaps were able to be distinguished from lesion sets created with no gaps. These results indicate that the end-systolic strain measured using intracardiac ME may be used to image the formation of lesions induced during an RF ablation procedure, in order to provide critical assessment of lesion viability during the interventional procedure.

Handheld reflectance confocal microscopy for the diagnosis of molluscum contagiosum: Histopathology and dermoscopy correlation

Handheld reflectance confocal microscopy may represent an adjunctive, fast, non-invasive tool for the diagnosis of molluscum contagiosum, revealing microscopic details closely related to histopathology, as demonstrated by this study evaluating 19 molluscum lesions in 11 patients. It permits the rapid examination of one or multiple skin lesions in real time and it is perfectly suitable for children.

TU‐B‐210‐02: MRg HIFU ‐ Advanced Approaches for Ablation and Hyperthermia

MR guided focused ultrasound (MRgFUS), or alternatively high‐intensity focused ultrasound (MRgHIFU), is approved for thermal ablative treatment of uterine fibroids and pain palliation in bone metastases. Ablation of malignant tumors is under active investigation in sites such as breast, prostate, brain, liver, kidney, pancreas, and soft tissue. Hyperthermia therapy with MRgFUS is also feasible, and may be used in conjunction with radiotherapy and for local targeted drug delivery. MRI allows in situ target definition and provides continuous temperature monitoring and subsequent thermal dose mapping during HIFU. Although MRgHIFU can be very precise, treatment of mobile organs is challenging and advanced techniques are required because of artifacts in MR temperature mapping, the need for intercostal firing, and need for gated HIFU or tracking of the lesion in real time. The first invited talk, “MR guided Focused Ultrasound Treatment of Tumors in Bone and Soft Tissue”, will summarize the treatment protocol and review results from treatment of bone tumors. In addition, efforts to extend this technology to treat both benign and malignant soft tissue tumors of the extremities will be presented. The second invited talk, “MRI guided High Intensity Focused Ultrasound – Advanced Approaches for Ablation and Hyperthermia”, will provide an overview of techniques that are in or near clinical trials for thermal ablation and hyperthermia, with an emphasis of applications in abdominal organs and breast, including methods for MRTI and tracking targets in moving organs.Learning Objectives: Learn background on devices and techniques for MR guided HIFU for cancer therapy Understand issues and current status of clinical MRg HIFU Understand strategies for compensating for organ movement during MRgHIFU Understand strategies for strategies for delivering hyperthermia with MRgHIFU CM ‐ research collaboration with Philips

TU‐B‐210‐01: MRg HIFU ‐ Bone and Soft Tissue Tumor Ablation

MR guided focused ultrasound (MRgFUS), or alternatively high‐intensity focused ultrasound (MRgHIFU), is approved for thermal ablative treatment of uterine fibroids and pain palliation in bone metastases. Ablation of malignant tumors is under active investigation in sites such as breast, prostate, brain, liver, kidney, pancreas, and soft tissue. Hyperthermia therapy with MRgFUS is also feasible, and may be used in conjunction with radiotherapy and for local targeted drug delivery. MRI allows in situ target definition and provides continuous temperature monitoring and subsequent thermal dose mapping during HIFU. Although MRgHIFU can be very precise, treatment of mobile organs is challenging and advanced techniques are required because of artifacts in MR temperature mapping, the need for intercostal firing, and need for gated HIFU or tracking of the lesion in real time. The first invited talk, “MR guided Focused Ultrasound Treatment of Tumors in Bone and Soft Tissue”, will summarize the treatment protocol and review results from treatment of bone tumors. In addition, efforts to extend this technology to treat both benign and malignant soft tissue tumors of the extremities will be presented. The second invited talk, “MRI guided High Intensity Focused Ultrasound – Advanced Approaches for Ablation and Hyperthermia”, will provide an overview of techniques that are in or near clinical trials for thermal ablation and hyperthermia, with an emphasis of applications in abdominal organs and breast, including methods for MRTI and tracking targets in moving organs.Learning Objectives: Learn background on devices and techniques for MR guided HIFU for cancer therapy Understand issues and current status of clinical MRg HIFU Understand strategies for compensating for organ movement during MRgHIFU Understand strategies for strategies for delivering hyperthermia with MRgHIFU CM ‐ research collaboration with Philips

TU-B-210-00: MR-Guided Focused Ultrasound Therapy in Oncology

MR guided focused ultrasound (MRgFUS), or alternatively high-intensity focused ultrasound (MRgHIFU), is approved for thermal ablative treatment of uterine fibroids and pain palliation in bone metastases. Ablation of malignant tumors is under active investigation in sites such as breast, prostate, brain, liver, kidney, pancreas, and soft tissue. Hyperthermia therapy with MRgFUS is also feasible, and may be used in conjunction with radiotherapy and for local targeted drug delivery. MRI allows in situ target definition and provides continuous temperature monitoring and subsequent thermal dose mapping during HIFU. Although MRgHIFU can be very precise, treatment of mobile organs is challenging and advanced techniques are required because of artifacts in MR temperature mapping, the need for intercostal firing, and need for gated HIFU or tracking of the lesion in real time. The first invited talk, “MR guided Focused Ultrasound Treatment of Tumors in Bone and Soft Tissue”, will summarize the treatment protocol and review results from treatment of bone tumors. In addition, efforts to extend this technology to treat both benign and malignant soft tissue tumors of the extremities will be presented. The second invited talk, “MRI guided High Intensity Focused Ultrasound – Advanced Approaches for Ablation and Hyperthermia”, will provide an overview of techniques that are in or near clinical trials for thermal ablation and hyperthermia, with an emphasis of applications in abdominal organs and breast, including methods for MRTI and tracking targets in moving organs. Learning Objectives: 1. Learn background on devices and techniques for MR guided HIFU for cancer therapy 2. Understand issues and current status of clinical MRg HIFU 3. Understand strategies for compensating for organ movement during MRgHIFU 4. Understand strategies for strategies for delivering hyperthermia with MRgHIFU CM - research collaboration with Philips

Novel endoscopic diagnosis for bladder cancer.

Advances in endoscopic imaging technology may improve sensitivity for the detection of bladder cancer and provide a more complete understanding of the urothelial landscape, and it also may lead to improved short-term and long-term cancer control. Fluorescence cystoscopy requires intravesical administration of a photosensitizing agent (5-aminolevulinic acid or hexaminolevulinate), and imaging with a blue-light endoscopy system demonstrably improves the detection of papillary and flat bladder lesions compared with conventional white-light cystoscopy. Prospective phase 3 clinical trials have demonstrated improved diagnostic ability, enhanced tumor resection, and a small but significant reduction in recurrence-free survival. Optical coherence tomography delineates subsurface microarchitecture information about bladder lesions in real time and has the ability to discriminate between noninvasive and invasive cancers. Narrow-band imaging may augment white-light cystoscopy by providing increased contrast between normal and abnormal tissue on the basis of neovascularity. Confocal laser endoscopy has been applied to the urinary tract using thinner probes adapted from use in gastrointestinal malignancies and provides exquisite images at microscopic resolution. More technology is on the horizon that may further enhance our ability to detect and accurately stage bladder tumors and distinguish benign from malignant or dysplastic lesions.

Surgical Targeting of Recurrent Thyroid Cancer Using a Novel Mixture of 99m-Technetium Macroaggregated Albumin and Indocyanine Green

Precise targeting has played a pivotal role in the success of surgery for recurrent differentiated thyroid cancers (DTCs). To improve on current targeting methods, we developed a novel technique using (99m)Tc-macroaggregated human serum albumin and indocyanine green (TIGMA), with which surgeons effectively target lesions in real time by radiofluorescence dual guidance. Seven patients with 10 recurrent DTC lesions were retrospectively enrolled in the study. Prior to the operation, we injected TIGMA into the target lesion under the guidance of ultrasonography. Resection was concurrently monitored using a gamma probe and a specially designed near infrared fluorescence camera. Outcomes were evaluated using imaging, surgical, and pathological records. In all enrolled cases, both injection of TIGMA and radiofluorescence dual guidance were well tolerated and easy to implement. The technical success rates were 100%, confirmed by final pathological examination, postoperative ultrasonography, and I-131 scan clearance. Complications such as temporary postoperative neck pain (n = 2) were minimal. TIGMA using radiofluorescence dual guidance facilitated the precise targeting of recurrent lesions. The entire procedure was feasible, safe, and successful. This method would help enhance surgical outcomes for recurrent DTCs.

Indocyanine green fluorescence imaging in the surgical management of liver cancers: Current facts and future implications

Imaging detection of liver cancers and identification of the bile ducts during surgery, based on the fluorescence properties of indocyanine green, has recently been developed in liver surgery. The principle of this imaging technique relies on the intravenous administration of indocyanine green before surgery and the illumination of the surface of the liver by an infrared camera that simultaneously induces and collects the fluorescence. Detection by fluorescence is based on the contrast between the (fluorescent) tumoral or peri-tumoral tissues and the healthy (non-fluorescent) liver. Results suggest that indocyanine green fluorescence imaging is capable of identification of new liver cancers and enables the characterization of known hepatic lesions in real time during liver resection. The purpose of this paper is to present the fundamental principles of fluorescence imaging detection, to describe successively the practical and technical aspects of its use and the appearance of hepatic lesions in fluorescence, and to expose the diagnostic and therapeutic perspectives of this innovative imaging technique in liver surgery.