The study, led by Meili Yu and colleagues at the Affiliated Taian City Central Hospital of Qingdao University, enrolled 32 patients with central-type lung cancer complicated by atelectasis who had either contraindications to bronchoscopy or in whom the procedure had failed. All were scanned and biopsied under contrast-enhanced ultrasound guidance between February 2022 and February 2025. The central question was deceptively simple: on a grayscale ultrasound image, can you actually tell where the tumor ends and the collapsed lung begins? If you cannot, any needle trajectory is a guess, and a guess that samples collapsed, inflamed, or necrotic tissue yields a false negative or a useless specimen.

The answer to that question is where the technique earns its keep. With conventional ultrasound alone, the interface between tumor and adjacent atelectatic lung was visible in only 40.6 percent of the patients, meaning that in nearly six out of ten cases the operator was effectively navigating blind. After an intravenous injection of an ultrasound contrast agent, that display rate jumped to 96.9 percent. In the 31 patients in whom the tumor-lung interface became clearly delineated, the enhancement dynamics themselves carried diagnostic information, because tumor tissue and collapsed lung tissue perfuse at measurably different speeds and with different patterns.

Those dynamics follow a consistent physiological logic. Lung cancers of the central type draw their blood supply from the bronchial arterial circulation, and the study found that all of the malignant lesions began to enhance between 10 and 17 seconds after contrast injection. The atelectatic lung, by contrast, is fed largely by the pulmonary arterial system, and in 80.7 percent of cases, 25 of the 31 evaluable patients, the collapsed tissue lit up earlier than the tumor. That timing difference gives the operator a real-time map: the region that enhances late is the tumor, the region that enhances early is the collapsed lung, and the needle can be steered toward the late-enhancing territory with a confidence that grayscale imaging cannot provide.

The enhancement pattern over time added a second layer of discrimination. In 83.9 percent of patients, 26 of 31, the central tumors showed what radiologists describe as a slow-in, fast-out pattern: contrast arrived late relative to the surrounding collapsed lung and then washed out quickly, a signature of the disorganized, arteriovenous-shunting microvasculature typical of malignant tissue. In 90.3 percent of lesions, 28 of 31, the tumor ultimately appeared hypo-enhanced relative to the reference tissue, reflecting the relatively sparse and abnormal vessel density within the tumor mass compared with the hyperemic collapsed lung around it. Together, the timing, the washout behavior, and the relative intensity form a composite target signature that the operator can follow on screen.

The technique also exposed a complication that would otherwise sabotage the biopsy silently. In nine patients, 28.1 percent of the cohort, the contrast scan revealed entirely non-enhancing areas within the lesion, corresponding to necrotic tissue where no viable tumor cells would be found. Sampling a necrotic core is one of the classic causes of non-diagnostic biopsies, and conventional imaging frequently cannot distinguish necrosis from viable tumor. By marking the non-enhancing zones in real time, the CEUS approach allowed the operators to aim for the enhancing, viable rim instead, which is precisely the material a pathologist needs to render a definitive diagnosis.

The bottom line for the 31 patients with a clearly visualized target was unambiguous: every single one underwent a successful puncture and yielded a definite pathological diagnosis. In a population defined by the failure or impossibility of the standard first-line diagnostic route, a 100 percent diagnostic sampling rate is a striking result. Equally important for a technique that involves passing a needle through the chest wall toward the mediastinum, the study reported no severe puncture-related complications, suggesting that the real-time vascular mapping provided by contrast enhancement does not merely improve yield but may also contribute to procedural safety by keeping the needle away from vessels and necrotic cavities.

Placed in context, the findings address a genuine clinical bottleneck. Central-type lung cancers arise in the large central airways, where bronchoscopic visualization and forceps biopsy are normally straightforward, which is why bronchoscopy dominates diagnostic algorithms for this tumor location. But the same tumors frequently obstruct the bronchus enough to collapse the downstream lung, and the resulting atelectasis creates a consolidated, fluid-filled region on ultrasound that can look remarkably similar to the tumor itself. Patients who cannot be bronchoscoped, whether because of respiratory failure, coagulopathy, vascular anatomy, or a failed attempt, have historically faced repeated attempts, more invasive surgical biopsies, or empiric treatment without histology. A percutaneous, ultrasound-guided alternative that works at the bedside, avoids ionizing radiation, and exploits the perfusion contrast between tumor and collapsed lung offers a pragmatic escape route.

The study’s design and scale warrant measured interpretation. It was retrospective, single-center, and involved 32 patients over a three-year window, and the authors themselves frame the work as an exploration of diagnostic value rather than a definitive trial. Selection is a consideration: these were patients in whom the technique was attempted, and the learning curve for CEUS-guided thoracic biopsy is real, since the operator must interpret contrast kinetics in real time while advancing a needle. The enhancement timings reported here, with tumors enhancing at 10 to 17 seconds and atelectatic lung typically earlier, provide a useful reference range, but they derive from one institution’s experience with one contrast agent and one scanner platform. Broader, ideally prospective, multicenter validation would be needed before the approach becomes a standard recommendation in guidelines.

Even with those caveats, the study adds a technically elegant tool to a problem that has few good answers. Contrast-enhanced ultrasound is inexpensive relative to CT or PET guidance, portable enough to be performed in an interventional suite or at the bedside, and free of the radiation burden of repeated CT-guided passes. By converting the perfusion differences between a tumor and the collapsed lung surrounding it into a visible, time-resolved map, the technique turns a previously ambiguous grayscale field into a target with defined borders, defined timing, and defined zones of viability. For the subset of lung cancer patients who are too sick or too difficult to bronchoscope, that transformation may be the difference between a specimen that changes treatment and a diagnostic dead end. The Taian team’s data, showing near-universal interface visualization, consistent tumor enhancement signatures, and complete diagnostic success without severe complications, make a credible case that CEUS-guided percutaneous biopsy deserves a defined place in the diagnostic algorithm for central lung cancer with atelectasis.

Subject of Research: Contrast-enhanced ultrasound-guided percutaneous biopsy for diagnosing central-type lung cancer with atelectasis in patients with bronchoscopy contraindications or failure

Article Title: Application of Contrast-Enhanced Ultrasound (CEUS)-guided percutaneous biopsy in the diagnosis of central-type lung cancer patients with bronchoscopy contraindications or failed

Article References: Yu, M., Zheng, Y., Zhang, M., Wang, L., Lyu, G., Zhang, C., & Liu, B. (2026). Application of Contrast-Enhanced Ultrasound (CEUS)-guided percutaneous biopsy in the diagnosis of central-type lung cancer patients with bronchoscopy contraindications or failed. BMC Medical Imaging. https://doi.org/10.1186/s12880-026-02840-z

Image Credits: AI Generated

DOI: 10.1186/s12880-026-02840-z

Keywords: contrast-enhanced ultrasound, CEUS, lung cancer, central-type lung cancer, atelectasis, percutaneous biopsy, bronchoscopy, tumor-lung interface, interventional radiology, cancer imaging, diagnostic biopsy, BMC Medical Imaging

The technique builds on a concept that has gained traction in adult interventional radiology over the past two decades. When a core biopsy needle pierces a hypervascular organ such as the liver or spleen, it leaves behind a channel that can continue to ooze after the procedure. Plugging that channel with embolic materials such as gelatin sponge slurry is one option, but thermal cauterisation offers a different mechanism: instead of mechanically blocking the tract, it coagulates the tissue along it, producing a zone of necrotic, sealed tissue that resists bleeding. Radiofrequency electrodes have been used for this purpose in adults, with studies reporting technical success rates as high as 98 percent and no major bleeding complications.

What has been missing, the Hong Kong team notes, is evidence in children. Paediatric oncology patients present particular challenges: smaller organs, thinner capsules, and tumours such as hepatoblastoma and hepatocellular carcinoma that can be both hypervascular and prone to seeding. The researchers therefore designed a retrospective review of consecutive patients aged eighteen or younger who underwent image-guided biopsy of a suspected intraabdominal tumour followed by tract cauterisation at their tertiary paediatric oncology centre between May 2019 and May 2024. The decision to cauterise was made at the operator’s discretion, based on the perceived risk of post-biopsy bleeding or tumour seeding.

The technical execution is elegant in its simplicity. All procedures were performed under general anaesthesia by three interventional radiologists with ten to twenty-five years of experience. A fifteen-gauge coaxial cannula was advanced into the target lesion under imaging guidance, and a sixteen-gauge core biopsy needle was passed through it to obtain tissue samples, with a median of three cores per lesion. Then, immediately after sampling, a sixteen-gauge microwave ablation antenna was inserted through the very same coaxial cannula. The antenna delivered microwave energy at forty watts in pulsed mode for at least thirty seconds, all under real-time ultrasound guidance. The radiologists watched for an echogenic zone, the bright cloud of microbubbles and tissue change that signals thermal coagulation, to spread until it fully covered the biopsied area. The antenna was then gradually withdrawn to the organ capsule, cauterising the entire tract on the way out.

The choice of a sixteen-gauge microwave antenna rather than a slimmer radiofrequency applicator was deliberate. International guidelines for paediatric liver tumour biopsies, including those from the Pediatric Hepatic International Tumour Trial, recommend obtaining at least ten cores of tissue with a sixteen-gauge device, which requires a robust outer cannula. Recent advances in microwave technology have allowed effective energy delivery through progressively smaller antennae, making it possible to match the calibre of the coaxial system already in place. Microwave energy also has physical advantages: it heats tissue faster and less dependently on tissue conductivity than radiofrequency current, producing broader coagulation zones in less time.

The results were unambiguous. Eleven patients, with a mean age of nine years and ranging from four months to eighteen years, underwent cauterisation of seventeen lesions, the vast majority in the liver. Every patient carried at least one risk factor for post-biopsy bleeding, such as a subcapsular lesion lying within a centimetre of the organ capsule, an avidly enhancing hypervascular mass, renal insufficiency, or cirrhosis. Technical success, defined as the absence of bleeding within the first twenty-four hours, was achieved in all seventeen procedures. Haemoglobin levels before and after the procedures were statistically indistinguishable, and follow-up extending to a mean of 562 days revealed no cases of tumour seeding along the biopsy tract.

Perhaps the most compelling evidence came from a single patient’s before-and-after experience. A seventeen-year-old girl with cirrhosis, portal hypertension and thrombocytopenia had previously undergone a biopsy of a hepatic lesion with the tract plugged using gelatin sponge slurry. Roughly thirty minutes later she developed massive haematemesis, vomiting around 450 millilitres of fresh blood. Contrast-enhanced CT revealed haemobilia, with contrast extravasating into the biliary tree, and her haemoglobin fell from 10.3 to 7.3 grams per decilitre, requiring two units of packed red cells and intensive care monitoring. When the lesion enlarged over the following year and a repeat biopsy was needed, the team used microwave tract cauterisation instead. This time there were no haemorrhagic complications at all, and the biopsy confirmed well-differentiated hepatocellular carcinoma.

The case illustrates why the authors argue that thermal cauterisation may outperform embolic plugging. Gelatin sponge can stop bleeding across the organ capsule, but it cannot necessarily control bleeding within the lesion itself or into the biliary system. Animal studies have shown radiofrequency cauterisation outperforming both gelatin sponge and histoacryl-lipiodol embolisation in reducing post-biopsy bleeding, including in coagulopathic subjects. Thermal ablation also sidesteps two other hazards of embolic agents: the risk of inadvertent non-target embolisation when liquid agents migrate, and the possibility of severe anaphylaxis, which has been reported with gelatin-based haemostatic materials. A recent meta-analysis further found that concurrent ablation of the biopsy tract combined with a coaxial technique reduces the rate of needle tract seeding in liver biopsies, and one laboratory study showed that cauterisation cut the proportion of viable tumour cells clinging to a biopsy needle from 17.9 percent to zero.

The authors are candid about the limitations. The cohort is small, the follow-up period is limited for assessing tumour seeding, and there is no control group, so the study should be read as an exploratory feasibility and safety assessment rather than definitive proof of superiority. There is also the question of cost: each microwave ablation antenna costs roughly 1,000 euros in the team’s locality, and only about 6.7 percent of the 165 intraabdominal tumour biopsies performed during the study period actually required tract cauterisation. The researchers suggest that the patients most likely to benefit are those with consumptive thrombocytopenia, coagulopathy, or tumours with high seeding risk such as hepatocellular carcinoma, and they point to newer, lower-profile microwave antennae designed for thyroid nodule ablation as potential lower-cost alternatives.

Even with those caveats, the study marks a meaningful step for paediatric interventional radiology. It demonstrates that a procedure refined in adults can be adapted to children using equipment already compatible with standard paediatric biopsy protocols, and that it can do so with an unblemished safety record in a deliberately high-risk cohort. For the small subset of children whose tumours and physiology make a routine biopsy genuinely dangerous, microwave tract cauterisation may offer a way to obtain the tissue that diagnosis demands while keeping the needle’s parting footprint sealed, sterile of viable tumour cells, and dry.

Subject of Research: Microwave ablation tract cauterisation after percutaneous biopsy of intraabdominal tumours in children

Article Title: Tract cauterisation by microwave ablation following percutaneous biopsy of intraabdominal tumour in children

Article References: Chen, W. L. J., Fung, K. F. K., Liu, A. P. Y., Chung, H. Y. P., Chiang, A. K. S., Cho, H. Y. D., & Kan, Y. L. E. (2025). Tract cauterisation by microwave ablation following percutaneous biopsy of intraabdominal tumour in children. CVIR Oncology, 1(1), Article 13. https://doi.org/10.1007/s44343-025-00015-1

Image Credits: AI Generated

DOI: 10.1007/s44343-025-00015-1

Keywords: microwave ablation, tract cauterisation, percutaneous biopsy, paediatric oncology, interventional radiology, liver tumours, hepatoblastoma, tumour seeding, post-biopsy haemorrhage, coaxial technique, ultrasound guidance, CVIR Oncology

The technology at the heart of the study, known as needle virtual reconstruction or NVR, addresses a fundamental bottleneck in image-guided interventions. Percutaneous procedures, in which needles are advanced through the skin to reach deep targets such as tumors or bone lesions, are commonly performed under cone-beam CT guidance. Cone-beam CT holds significant advantages over conventional CT in the interventional suite: it avoids the constraints of bore size and gantry orientation, and it integrates seamlessly with real-time fluoroscopy, allowing clinicians to visualize instruments continuously during an intervention. But there is a catch. Most commercially available guidance systems allow operators to plan a needle trajectory on an initial CBCT acquisition and monitor progress using fluoroscopy overlays, yet evaluating the needle’s latest position within the three-dimensional volume requires acquiring an entirely new CBCT scan. Each additional acquisition adds seconds to minutes of procedure time and delivers another dose of ionizing radiation to both patient and operator.

NVR software, marketed as Needle ASSIST with Stereo 3D by GE HealthCare, sidesteps this problem by mathematical triangulation. Instead of a full volumetric rotation, the system needs only two fluoroscopic projections captured with the needle in place. Because the needle’s silhouette appears from two different angles, and because the geometry of the fluoroscopic gantry is precisely known, the software can reconstruct the needle’s three-dimensional position and map it into the coordinate space of the initial planning CBCT. The virtual needle then appears alongside the planned trajectory, giving the operator an immediate, radiation-light assessment of whether the instrument is on course, short of target, or straying toward danger. The workflow relies on two automatically generated views: a so-called bull’s eye view that looks directly down the barrel of the needle to guide entry point and orientation, and a progress view that displays the full needle shaft to track insertion depth.

To validate this approach rigorously, the research team conducted a retrospective single-center cohort study at a large cancer hospital, with institutional review board approval under protocol 16-402. They enrolled consecutive patients who underwent percutaneous image-guided interventions using NVR software between January 2023 and November 2024. The final cohort comprised 40 procedures in 40 cancer patients: 37 biopsies and 3 kyphoplasties, the latter being vertebral augmentation procedures in which cement is delivered into collapsed vertebrae. All spinal interventions followed a transpedicular approach, threading the needle through the bony pedicle of the vertebra, while other procedures used anatomically safe paths selected to avoid critical structures. Every case followed societal guidelines for anticoagulation management and bleeding risk, and procedures were performed under monitored anesthesia care or general anesthesia by an interventional radiologist with more than two decades of experience.

The imaging protocol followed a standardized sequence. Before any needle was inserted, an initial cone-beam CT was acquired using a 200-degree rotational scan at 40 degrees per second over roughly five seconds, capturing between 147 and 244 frames depending on the suite. Variable kVp and mAs settings dynamically compensated for differences in patient anatomy, and the reconstructed three-dimensional volume spanned a 24-centimeter-diameter cylinder in a 512-cubed matrix. The trajectory was planned tableside by defining target and entry points, and the planned line was overlaid on live fluoroscopy. Bone anatomy derived from the initial CBCT was superimposed to confirm accurate registration and flag any patient movement, with tableside adjustments made as needed. After needle insertion, the virtual reconstruction was generated automatically from two fluoroscopic projections, and critically, a final CBCT was acquired as ground truth to validate needle position before the intervention proceeded. It is this final scan that allowed the team to measure, in hindsight, how well the virtual needle matched reality.

The validation methodology was deliberately conservative. The researchers registered the pre-insertion planning CBCT with the final ground-truth CBCT based on bony landmarks, without displaying the virtual reconstruction. They then measured the maximal distance between the virtual needle tip and the actual needle tip on the bull’s eye view using a dedicated imaging workstation. Two authors performed the measurements independently and reached consensus, with a third author arbitrating disagreements. In parallel, they assessed safety agreement: reviewers first confirmed on the final CBCT that all real needle trajectories avoided critical structures, then checked whether the software’s virtual predictions had correctly indicated those same safe paths. The results were unambiguous. The median discrepancy between virtual and actual needle tip positions was 1.3 millimeters, with an interquartile range of 0.9 to 2.2 millimeters, and the virtual reconstructions correctly predicted the safety profile in every case, with no erroneous depiction of a needle touching a critical structure.

Procedural metrics from the study paint a picture of efficient, low-dose practice. The median procedure duration was 57.5 minutes, median fluoroscopy time was 128 seconds, and the median total dose area product, combining fluoroscopy and CBCT, was 28.9 Gy·cm². Technical success, defined as placement of the needle tip within the boundaries of the targeted lesion or bone on the final CBCT, was achieved in 100 percent of cases. For the applicable tumor cases, the median target lesion size was 24 millimeters. The cohort itself skewed older and heavier, with a median age of 71 years and a median body mass index of 26.1, a detail that matters because larger patients typically require higher radiation doses for adequate image quality. Despite this, the reported doses remained within published reference levels for comparable procedures, suggesting that the guidance software did not inflate radiation burden even in technically challenging anatomy.

The broader implications reach beyond the operating suite. Previous research has suggested that virtual needle guidance technologies can meaningfully cut radiation exposure by eliminating the multiple verification CBCT scans traditionally interspersed through needle positioning. One earlier study cited by the authors reported reductions in air kerma and dose area product of 27 percent and 35 percent respectively when such technology replaced repeated volumetric checks. The accuracy figures now reported go further, raising the possibility that even the final confirmation CBCT, acquired after every needle placement in this study, might eventually be dispensable for select cases, with two quick fluoroscopic views providing sufficient reassurance more simply and faster. The authors are careful on this point: eliminating the final CBCT would require further evaluation, including a randomized or controlled comparison, before it could become standard practice. Guidance software of this kind has already found roles in musculoskeletal intervention, endoleak treatment, and thermal ablation, but the new study is distinctive in specifically quantifying reconstruction accuracy against a ground-truth scan.

The study is not without caveats, and the authors lay them out candidly. It was a single-center retrospective analysis spanning a variety of anatomical targets, so multi-institutional validation would strengthen the findings. The absence of a control group means the team cannot definitively attribute reductions in radiation dose or procedure time to the software itself. Accuracy was measured in a two-dimensional plane on the bull’s eye view rather than in full three dimensions, which would offer a more complete picture of reconstruction error. And the operating physician’s substantial experience, more than twenty years of practice, may have influenced fluoroscopy times and radiation doses in ways that might not generalize to less seasoned operators. There is also a commercial relationship to note: two of the authors serve as consultants for GE HealthCare, the manufacturer of the software and imaging systems used in the study, and the research received support in part through a National Institutes of Health cancer center support grant.

Even with those limitations, the study marks a persuasive step toward smarter, leaner image-guided surgery. The vision it sketches is an interventional suite in which a single volumetric scan at the start of a procedure anchors all subsequent navigation, and every subsequent question about needle position is answered with two milliseconds-fast fluoroscopic frames rather than a full rotation of the C-arm. For cancer patients, who often undergo repeated biopsies and ablative procedures over the course of their illness, the cumulative savings in radiation, anesthesia time, and waiting could be substantial. For the clinicians, a trustworthy virtual needle means fewer interruptions, faster workflows, and continuous three-dimensional awareness of where their instrument truly sits relative to vessels, nerves, and bone. If larger controlled studies confirm these results, the humble biopsy needle may soon travel through the body shadowed by a digital twin that is accurate to little more than a millimeter, and the era of confirming positions with repeated scans may give way to one of calculating them.

Subject of Research: Accuracy and safety of virtual needle reconstruction software during cone-beam CT-guided percutaneous procedures in cancer patients

Article Title: Virtual reconstruction to assess needle position during percutaneous procedures performed under cone-beam computed tomography: safety and accuracy

Article References: Geevarghese, R., Kiely, L., Petre, E. N., Solomon, S. B., & Cornelis, F. H. (2026). Virtual reconstruction to assess needle position during percutaneous procedures performed under cone-beam computed tomography: safety and accuracy. CVIR Oncology, 2(1), Article 9. https://doi.org/10.1007/s44343-026-00042-6

Image Credits: AI Generated

DOI: 10.1007/s44343-026-00042-6

Keywords: cone-beam CT, needle virtual reconstruction, interventional radiology, percutaneous biopsy, image-guided procedures, fluoroscopy, radiation dose, cancer, technical success, kyphoplasty, needle guidance, medical imaging