Pulmonary masses: initial results of cone-beam CT guidance with needle planning software for percutaneous lung biopsy

Determinants of radiation exposure during mobile cone-beam CT-guided robotic-assisted bronchoscopy

BACKGROUND AND OBJECTIVE

Robotic-assisted bronchoscopy (RAB) is an emerging modality to sample pulmonary lesions. Cone-beam computed tomography (CBCT) can be incorporated into RAB. We investigated the magnitude and predictors of patient and staff radiation exposure during mobile CBCT-guided shape-sensing RAB.

METHODS

Patient radiation dose was estimated by cumulative dose area product (cDAP) and cumulative reference air kerma (cRAK). Staff equivalent dose was calculated based on isokerma maps and a phantom simulation. Patient, lesion and procedure-related factors associated with higher radiation doses were identified by logistic regression models.

RESULTS

A total of 198 RAB cases were included in the analysis. The median patient cDAP and cRAK were 10.86 Gy cm2 (IQR: 4.62-20.84) and 76.20 mGy (IQR: 38.96-148.38), respectively. Among staff members, the bronchoscopist was exposed to the highest median equivalent dose of 1.48 μSv (IQR: 0.85-2.69). Both patient and staff radiation doses increased with the number of CBCT spins and targeted lesions (p < 0.001 for all comparisons). Patient obesity, negative bronchus sign, lesion size <2.0 cm and inadequate sampling by on-site evaluation were associated with a higher patient dose, while patient obesity and inadequate sampling by on-site evaluation were associated with a higher bronchoscopist equivalent dose.

CONCLUSION

The magnitude of patient and staff radiation exposure during CBCT-RAB is aligned with safety thresholds recommended by regulatory authorities. Factors associated with a higher radiation exposure during CBCT-RAB can be identified pre-operatively and solicit procedural optimization by reinforcing radiation protective measures. Future studies are needed to confirm these findings across multiple institutions and practices.

Computed-Tomography-Guided Lung Biopsy: A Practice-Oriented Document on Techniques and Principles and a Review of the Literature

Computed tomography (CT)-guided lung biopsy is one of the oldest and most widely known minimally invasive percutaneous procedures. Despite being conceptually simple, this procedure needs to be performed rapidly and can be subject to meaningful complications that need to be managed properly. Therefore, knowledge of principles and techniques is required by every general or interventional radiologist who performs the procedure. This review aims to contain all the information that the operator needs to know before performing the procedure. The paper starts with the description of indications, devices, and types of percutaneous CT-guided lung biopsies, along with their reported results in the literature. Then, pre-procedural evaluation and the practical aspects to be considered during procedure (i.e., patient positioning and breathing) are discussed. The subsequent section is dedicated to complications, with their incidence, risk factors, and the evidence-based measures necessary to both prevent or manage them; special attention is given to pneumothorax and hemorrhage. After conventional CT, this review describes other available CT modalities, including CT fluoroscopy and cone-beam CT. At the end, more advanced techniques, which are already used in clinical practice, like fusion imaging, are included.

Pneumothorax and pulmonary hemorrhage after C-arm cone-beam computed tomography-guided percutaneous transthoracic lung biopsy: incidence, clinical significance, and correlation

OBJECTIVE

This study aimed to assess the incidence and clinical significance of pneumothorax (PTX) and pulmonary hemorrhage (PH) after percutaneous transthoracic lung biopsy (PTLB) guided by C-arm cone-beam computed tomography (CBCT). Furthermore, this study aimed to examine the relationships between PTX and PH with demographics, clinical characteristics, imaging, and PTLB parameters.

METHODS

A retrospective analysis was conducted on 192 patients who underwent PTLB at our hospital between January 2019 and October 2022. Incidences of PTX and PH were recorded. PTX was considered clinically significant if treated with chest tube insertion (CTI), and PH if treated with bronchoscopes or endovascular treatments. The various factors on PTX and PH were analyzed using the Chi-squared test and Student t-test. Logistic regression analyses were then used to determine these factors on the correlation to develop PTX and PH.

RESULTS

PTX occurred in 67/192 cases (34.9%); CTI was required in 5/67 (7.5%). PH occurred in 63/192 cases (32.8%) and none of these cases required bronchoscopes or endovascular treatments. Lesion diameter (ORPTX = 0.822; ORPH = 0.785), presence of pulmonary emphysema (ORPH = 2.148), the number of samples (ORPH = 1.834), the use of gelfoam (ORPTX = 0.474; ORPH = 0.341) and ablation (ORPTX = 2.351; ORPH = 3.443) showed statistically significant correlation to PTX and PH.

CONCLUSIONS

CBCT-guided PTLB is a safe and effective method for performing lung biopsies. The use of gelfoam has been shown to reduce the occurrence of PTX and PH. However, caution should be exercised when combining radiofrequency ablation with PTLB, as it may increase the risk of PTX and PH.

C-Arm Cone-Beam CT Virtual Navigation versus Conventional CT Guidance in the Transthoracic Lung Biopsy: A Case-Control Study

C-arm cone-beam computed tomography (CBCT) virtual navigation-guided lung biopsy has been developed in the last decade as an alternative to conventional CT-guided lung biopsy. This study aims to compare the biopsy accuracy and safety between these two techniques and explores the risk factors of biopsy-related complications. A total of 217 consecutive patients undergoing conventional CT- or C-arm CBCT virtual navigation-guided lung biopsy from 1 June 2018 to 31 December 2019 in this single-center were retrospectively reviewed. Multiple factors (e.g., prior emphysema, lesion size, etc.) were compared between two biopsy techniques. The risk factors of complications were explored by using logistic regression. The patients’ median age and male-to-female ratio were 63 years and 2.1:1, respectively. Eighty-two (82) patients (37.8%) underwent conventional CT-guided biopsies, and the other 135 patients (62.2%) C-arm CBCT virtual navigation-guided biopsies. Compared with patients undergoing C-arm CBCT virtual navigation-guided lung biopsies, patients undergoing conventional CT-guided lung biopsies showed higher needle repositioning rate, longer operation time, and higher effective dose of X-ray (52.4% vs. 6.7%, 25 min vs. 15 min, and 13.4 mSv vs. 7.6 mSv, respectively; p < 0.001, each). In total, the accurate biopsy was achieved in 215 of 217 patients (99.1%), without a significant difference between the two biopsy techniques (p = 1.000). The overall complication rates, including pneumothorax and pulmonary hemorrhage/hemoptysis, are 26.3% (57/217), with most minor complications (56/57, 98.2%). The needle repositioning was the only independent risk factor of complications with an odds ratio of 6.169 (p < 0.001). In conclusion, the C-arm CBCT virtual navigation is better in percutaneous lung biopsy than conventional CT guidance, facilitating needle positioning and reducing radiation exposure. Needle repositioning should be avoided because it brings about more biopsy-related complications.

Cone-Beam CT-Guided Lung Biopsies: Results in 94 Patients

BACKGROUND

The aim of this study was to evaluate the diagnostic capacity of Cone-Beam computed tomography (CT)-guided transthoracic percutaneous biopsies on lung lesions in our setting and to detect risk factors for possible complications.

METHODS

Retrospective study of 98 biopsies in 94 patients, performed between May 2017 and January 2020. To obtain them, a 17G coaxial puncture system and a Siemens Artis Zee Floor vc21 archwire were used. Descriptive data of the patients, their position at the time of puncture, location and size of the lesions, number of cylinders extracted, and complications were recorded. Additionally, the fluoroscopy time used in each case, the doses/area and the estimated total doses received by the patients were recorded.

RESULTS

Technical success was 96.8%. A total of 87 (92.5%) malignant lesions and 3 (3.1%) benign lesions were diagnosed. The sensitivity was 91.5% and the specificity was 100%. We registered three technical failures and three false negatives initially. Complications included 38 (38.8%) pneumothorax and 2 (2%) hemoptysis cases. Fluoroscopy time used in each case was 4.99 min and the product of the dose area is 11,722.4 microGy/m².

CONCLUSION

The transthoracic biopsy performed with Cone-Beam CT is accurate and safe in expert hands for the diagnosis of lung lesions. Complications are rare and the radiation dose used was not excessive.

Development of a hemoptysis risk prediction model for patients following CT-guided transthoracic lung biopsy

Background

Computed tomography-guided transthoracic needle biopsy (CT-TNB) is a widely used method for diagnosis of lung diseases; however, CT-TNB-induced bleeding is usually unexpected and this complication can be life-threatening. The aim of this study was to develop and validate a predictive model for hemoptysis following CT-TNB.

Methods

A total of 436 consecutive patients who underwent CT-TNB from June 2016 to December 2017 at a tertiary hospital in China were divided into derivation (n = 307) and validation (n = 129) cohorts. We used LASSO regression to reduce the data dimension, select variables and determine which predictors were entered into the model. Multivariate logistic regression was used to develop the predictive model. The discrimination capacity of the model was evaluated by the area under the receiver operating characteristic curve (AUROC), the calibration curve was used to test the goodness-of-fit of the model, and decision curve analysis was conducted to assess its clinical utility.

Results

Five predictive factors (diagnosis of the lesion, lesion characteristics, lesion diameter, procedure time, and puncture distance) selected by LASSO regression analysis were applied to construct the predictive model. The AUC was 0.850 (95% confidence interval [CI], 0.808–0.893) in the derivation, and 0.767 (95% CI, 0.684–0.851) in the validation. The model showed good calibration consistency (p > 0.05). Moreover, decision curve analysis indicated its clinical usefulness.

Conclusion

We established a predictive model that incorporates lesion features and puncture parameters, which may facilitate the individualized preoperative prediction of hemoptysis following CT-TNB.

Non-diagnostic Results of Percutaneous Transthoracic Needle Biopsy: A Meta-analysis

Non-diagnostic results can affect the diagnostic performance of percutaneous transthoracic needle biopsy (PTNB) but have not been critically meta-analyzed yet. To meta-analyze the incidence and malignancy rate of non-diagnostic results, 3-by-2 table approaches rather than the conventional 2-by-2 approaches are needed to know its impact on the diagnostic performance of PTNB. A systematic literature search identified studies evaluating the diagnostic performance of PTNB with extractable outcomes. A total of 143 studies with 35,059 biopsies were included. The pooled incidence of non-diagnostic results was 6.8% (95% CI, 6.0-7.6%; I² = 0.91). The pooled malignancy rate of non-diagnostic results was 59.3% (95% CI, 51.7-66.8%; I² = 0.80), and was correlated with the prevalence of malignancy (correlation coefficient, 0.66; 95% CI, 0.42-0.91). Pooled percentage decrease of sensitivity and specificity due to non-diagnostic results were 4.5% (95% CI, 3.2-5.7%; I² = 0.64) and 10.7% (95% CI, 7.7-13.7%; I² = 0.70), respectively, and the pooled incidence of non-diagnostic results was 4.4% (95% CI, 3.2-5.8%; I² = 0.83) in lesions ultimately diagnosed as malignancies and 10.4% (95% CI, 7.5-13.8%; I² = 0.74) in benign disease. In conclusion, non-diagnostic results averagely occurred in 6.8% of PTNB and more than half of the results were malignancies. The non-diagnostic results decreased specificity and sensitivity by 10.7% and 4.5%, respectively, demanding efforts to minimize the non-diagnostic results in PTNB.

Transthoracic Rebiopsy for Mutation Analysis in Lung Adenocarcinoma: Outcomes and Risk Factors for the Acquisition of Nondiagnostic Specimens in 199 Patients

PURPOSE

To determine the outcomes of transthoracic rebiopsy for epidermal growth factor receptor (EGFR) mutation in patients with lung adenocarcinoma and to explore the clinical and procedure-related risk factors for the acquisition of nondiagnostic rebiopsy specimens.

PATIENTS AND METHODS

We retrospectively reviewed 367 patients with lung adenocarcinoma who underwent transthoracic core needle biopsy for mutation analysis from September 2011 to October 2016. Of these, 199 patients underwent rebiopsy. Patient characteristics, treatment history, target lesion characteristics, and procedure-related factors were evaluated. The adequacy rate of specimens for mutation analysis was evaluated. Univariable and multivariable analyses were performed to determine the independent predictors of nondiagnostic specimens.

RESULTS

Ninety percent of specimens (179 of 199) were adequate for mutation analysis. The EGFR mutation (exon 18-21) was 65% (117 of 179) and the EGFR T790M mutation 33% (59 of 179) of specimens. In univariable analysis, an internal low-attenuation area in the target lesion (P = .001) and pleural contact (P = .004) on computed tomography were significant risk factors for nondiagnostic specimens. In multivariable analysis, an internal low-attenuation area in the target lesion (odds ratio = 7.333; 95% confidence interval, 1.755-30.633; P = .006) was an independent predictor for acquisition of nondiagnostic specimens.

CONCLUSION

Image-guided transthoracic rebiopsy to obtain specimens for mutation analysis in lung adenocarcinoma provides high diagnostic accuracy, with a low rate of nondiagnostic specimens. The presence of internal low-attenuation area in the target lesion on computed tomography was an independent predictor for acquiring nondiagnostic specimens.

Percutaneous Computed Tomography-Guided Lung Biopsies using a Virtual Navigation Guidance: Our Experience

OBJECTIVE

To evaluate the effectiveness of a virtual CT-guided navigation system (Sirio-MASMEC Biomed) in performing lung biopsies, with greater attention to lesions smaller than 1 cm, compared to the traditional procedure.

METHODS

This study was approved by the Ethics Committee of our Institute. Two hundred patients were prospectively selected. Of these, 100 were subjected to percutaneous procedure with the use of Sirio and 100 to traditional CT-guided percutaneous procedure. The two methods were compared in terms of absorbed dose, procedure time, complications, and number of non-diagnostic specimens (diagnostic success).

RESULTS

Sirio has shown a significant reduction in the absorbed dose and procedure times (p < 0.05), with a lower incidence of complications compared to the traditional procedure. Sirio has also allowed to carry out biopsies of lesions' diameter ≤10 mm, obtaining fewer non diagnostic specimens thus resulting more effective in terms of diagnostic success.

CONCLUSIONS

The use of Sirio in sampling biopsy showed a statistically significant reduction in terms of performed scans and procedural time with lower incidence of post-procedural complications compared to the traditional percutaneous procedure, especially for lesions ≤10 mm. The best diagnostic result, the reduction of the dose absorbed and procedural complications makes the procedures more reliable, safety and less invasive. In addition, the reduction of execution time will increase the number of daily interventional procedures improving clinical management.

Transarterial chemoembolization plus multi-imaging-guided radiofrequency ablation for elimination of hepatocellular carcinoma nodules measuring 3.1 to 5.0 cm: a single-center study

Objective This study was performed to determine whether transarterial chemoembolization (TACE) plus multi-imaging-guided radiofrequency ablation (MIG-RFA) can completely eliminate 3.1- to 5.0-cm hepatocellular carcinoma (HCC) nodules and identify factors that may influence the complete elimination rate (CER) of this therapy. Methods Patients who underwent TACE+MIG-RFA for initial treatment of HCC from January 2008 to January 2016 were retrospectively reviewed. In total, 162 patients with 216 HCC nodules (3.1-5.0 cm) were enrolled. TACE was performed first; MIG-RFA was performed 2 to 4 weeks later. Contrast-enhanced computed tomography was performed 1, 3, 6, and 12 months after TACE+MIG-RFA. If tumor enhancement was not detected by the end of the 12-month follow-up, the lesion was considered completely eliminated. Additional TACE+MIG-RFA was performed for residual lesions. The CER was calculated 12 months after the last therapy. Factors that may influence the CER were analyzed. Results In total, 207 (95.8%) nodules showed no residual lesions and were completely eliminated after one or more TACE+MIG-RFA sessions. Nine (4.2%) nodules were incompletely eliminated even with repeated TACE+MIG-RFA. Tumor location was the only significant prognostic factor influencing the CER. Conclusions TACE+MIG-RFA can eliminate 3.1- to 5.0-cm HCC nodules; the tumor location may affect the treatment outcome.

Computed Tomography-Assisted Thoracoscopic Surgery: A Novel, Innovative Approach in Patients With Deep Intrapulmonary Lesions of Unknown Malignant Status

OBJECTIVES

Minimally invasive resection of small, deep intrapulmonary lesions can be challenging due to the difficulty of localizing them during video-assisted thoracoscopic surgery (VATS). We report our preliminary results evaluating the feasibility of an image-guided, minimally invasive, 1-stop-shop approach for the resection of small, deep intrapulmonary lesions in a hybrid operating room (OR).

MATERIALS AND METHODS

Fifteen patients (5 men, 10 women; mean age, 63 years) with a total of 16 solitary, deep intrapulmonary nodules of unknown malignant status were identified for intraoperative wire marking. Patients were placed on the operating table for resection by VATS. A marking wire was placed within the lesion under 3D laser and fluoroscopic guidance using a cone beam computed tomography system. Then, wedge resection by VATS was performed in the same setting without repositioning the patient.

RESULTS

Complete resection with adequate safety margins was confirmed for all lesions. Marking wire placement facilitated resection in 15 of 16 lesions. Eleven lesions proved to be malignant, either primary or secondary; 5 were benign. Mean lesion size was 7.7 mm; mean distance to the pleural surface was 15.1 mm (mean lesion depth-diameter ratio, 2.2). Mean procedural time for marking wire placement was 35 minutes; mean VATS duration was 36 minutes.

CONCLUSIONS

Computed tomography-assisted thoracoscopic surgery is a new, safe, and effective procedure for minimally invasive resection of small, deeply localized intrapulmonary lesions. The benefits of computed tomography-assisted thoracoscopic surgery are 1. One-stop-shop procedure, 2. Lower risk for the patient (no patient relocation, no marking wire loss), and 3. No need to coordinate scheduling between the CT room and OR.

Percutaneous needle biopsy of mediastinal masses under C-arm conebeam CT guidance: diagnostic performance and safety

The aim of this study is to evaluate the feasibility of percutaneous needle biopsy of mediastinal masses under conebeam computed tomography (CBCT) and "XperGuide" navigation guidance. From September 2013 to April 2016, 40 patients (25 men and 15 women; mean age 52.5 years; range 18.7-86.4 years) with 40 mediastinal masses underwent CBCT-/"XperGuide"-guided percutaneous needle biopsies. Technical success, sensibility, specificity, positive predictive value (ppv), negative predictive value (npv) and complications rate were evaluated. Technical success evaluated as the correct positioning of the needle inside the lesion was 100%. Based on histopathological diagnosis, 2 of 40 biopsies (5%) resulted a false negative. Diagnostic accuracy was 95%, sensitivity was 95%, specificity was 100%, ppv was 100%, and npv was 33%. The mean total procedure time was 32 min (range 15-60 min) revealing a reduction in time comparing the first group of 20 patients (mean time 45 min) with the last group of 20 patients (mean time 17 min). No major complications were recorded. Only three patients (7.5%) had mild pneumothorax as demonstrated by post-procedural CBCT, resolved spontaneously. CBCT/"XperGuide" navigation system is a new, safe and accurate technique that can be used as guidance for mediastinal mass biopsies. It also permits the use of CT machines for diagnostic examinations relieving them from interventional procedures burden.

A Systematic Review and Meta-Analysis of C-Arm Cone-Beam CT-Guided Percutaneous Transthoracic Needle Biopsy of Lung Nodules

Background

A systematic review and meta-analysis of all available publications was performed to evaluate the diagnostic accuracy of percutaneous transthoracic needle biopsy (PTNB) using a C-Arm Cone-Beam CT (CBCT) system in patients with lung nodules.

Material/Methods

Thedatabases of PUBMED, OVID, EBSCO, EMBASE, and China National Knowledge Infrastructure (CNKI) were systematically searched for relevant original articles on the diagnostic accuracy of CBCT-guided PTNB for the diagnosis of nodules in the lungs. Diagnostic indices including sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR) and diagnostic score (DS) were calculated. Moreover,summary receiver operating characteristic curves (SROC) were constructed with Stata (version 13.0), Rev Man (version 5.3), and Meta-disc (version 1.4) software. Other clinical indices such as incidence of complications were also recorded.

Results

Eight studies met the inclusion and exclusion criteria for the meta-analysis. The pooled sensitivity, specificity, PLR, NLR, DOR, DS, and SROC with 95% confidence intervals were 0.96 (0.93–0.98), 1.00 (0.91–1.00), 711.15 (9.48–53325.89), 0.04 (0.02–0.07), 16585.29 (284.88–9.7e+05), 9.72 (5.65–13.78), and 0.99 (0.97–0.99), respectively. The incidence of pneumothorax and hemorrhage was 10–29.27% and 1.22–47.25%, respectively.

Conclusions

CBCT-guided PTNB has an acceptable rate of complications and is associated with a reasonable radiation exposure. Moreover, it is a highly accurate and safe technique for the diagnosis of lung nodules and can be recommended to be used in routine clinical practice.

Prospective Randomized Trial for Image-Guided Biopsy Using Cone-Beam CT Navigation Compared with Conventional CT

PURPOSE

To compare cone-beam computed tomography (CT) navigation vs conventional CT image guidance during biopsies.

MATERIALS AND METHODS

Patients scheduled for image-guided biopsies were prospectively and randomly assigned to conventional CT guidance vs cone-beam CT navigation. Radiation dose, accuracy of final needle position, rate of histopathologic diagnosis, and number of needle repositions to reach the target (defined as pullback to adjust position) were compared.

RESULTS

A total of 58 patients (mean age, 57 y; 62.1% men) were randomized: 29 patients underwent 33 biopsies with CT guidance and 29 patients with 33 lesions underwent biopsy with cone-beam CT navigation. The average body mass index (BMI) was similar between groups, at 28.8 kg/m(2) ± 6.55 (P = .18). There was no difference between groups in terms of patient and lesion characteristics (eg, size, depth). The average lesion size was 29.1 ± 12.7mm for CT group vs 32.1mm ±16.8mm for cone-beam CT group (P < 0.59). Location of lesions was equally divided between the 2 groups, 20 lung lesions, 18 renal lesions and 20 other abdominal lesions. Mean number of needle repositions in the cone-beam CT group was 0.3 ± 0.5, compared with 1.9 ± 2.3 with conventional CT (P < .001). The average skin entry dose was 29% lower with cone-beam CT than with conventional CT (P < .04 accounting for BMI). The average estimated effective dose for the planning scan from phantom data was 49% lower with cone-beam CT vs conventional CT (P = .018). Accuracy, defined as the difference between planned and final needle positions, was 4.9 mm ± 4.1 for the cone-beam CT group, compared with 12.2 mm ± 8.1 for conventional CT (P < .001). Histopathologic diagnosis rates were similar between groups, at 90.9% for conventional CT and 93.9% for cone-beam CT (P = .67).

CONCLUSIONS

Cone-beam CT navigation for biopsies improved targeting accuracy with fewer needle repositions, lower skin entry dose, and lower effective dose for planning scan, and a comparable histopathologic diagnosis rate.

Flat detector cone-beam CT-guided percutaneous needle biopsy of mediastinal lesions: preliminary experience

PURPOSE

The purpose of this study was to evaluate the usefulness of flat detector cone-beam CT-guided CBCT percutaneous needle biopsy (PNB) of mediastinal lesions.

METHODS

A total of 100 patients with 100 solid mediastinal lesions were retrospectively enrolled to undergo percutaneous needle biopsy (PNB) procedures. The mean diameter of lesions was 4.4 ± 1.8 cm (range 1.8-9.0 cm). The needle path was carefully planned and calculated on the CBCT virtual navigation guidance system, which acquired 3D CT-like cross-sectional images. Diagnostic performance, procedure details, complication rate, and patient radiation exposure were investigated.

RESULTS

The technical success rate of PNB under CBCT virtual navigation system was 100 % (100/100). The sensitivity, specificity, and accuracy of PNB of small nodules under iGuide CBCT virtual navigation guidance were 95.1 % (79/83), 100 % (12/12), and 95.7 % (91/95), respectively. The number of biopsies and CBCT acquisitions were 2.6 ± 1.2 (range 1-6) and 3.0 ± 1.1 (range 2-8), respectively. Complications occurred in five (5.0 %) cases. The mean total procedure time was 11.70 ± 3.44 min (range 6-27 min), resulting in a mean exposure dose of 9.7 ± 4.3 mSv.

CONCLUSION

Flat detector cone-beam CT-guided PNB is an accurate and safe diagnostic method for mediastinal lesions.

Radiation exposure of the interventional radiologist during percutaneous biopsy using a multiaxis interventional C-arm CT system with 3D laser guidance: a phantom study

OBJECTIVE

Evaluation of absolute radiation exposure values for interventional radiologists (IRs) using a multiaxis interventional flat-panel C-arm cone beam CT (CBCT) system with three-dimensional laser guidance for biopsy in a triple-modality, abdominal phantom.

METHODS

In the phantom, eight lesions were punctured in two different angles (in- and out-of-plane) using CBCT. One C-arm CT scan was performed to plan the intervention and one for post-procedural evaluation. Thermoluminescent dosemeters (TLDs) were used for dose measurement at the level of the eye lens, umbilicus and ankles on a pole representing the IRs. All measurements were performed without any lead protection. In addition, the dose-area product (DAP) and air kerma at the skin entrance point was documented.

RESULTS

Mean radiation values of all TLDs were 190 µSv for CBCT (eye lens: 180 µS, umbilicus: 230 µSv, ankle: 150 µSv) without a significant difference (p > 0.005) between in- and out-of-plane biopsies. In terms of radiation exposure of the phantom, the mean DAP was not statistically significantly different (p > 0.05) for in- and out-of-plane biopsies. Fluoroscopy showed a mean DAP of 7 or 6 μGym(2), respectively. C-arm CT showed a mean DAP of 5150 or 5130 μGym(2), respectively.

CONCLUSION

In our setting, the radiation dose to the IR was distinctly high using CBCT. For dose reduction, it is advisable to pay attention to lead shielding, to increase the distance to the X-ray source and to leave the intervention suite for C-arm CT scans.

ADVANCES IN KNOWLEDGE

The results indicate that using modern navigation tools and CBCT can be accompanied with a relative high radiation dose for the IRs since detector angulation can make the use of proper lead shielding difficult.

Percutaneous Transthoracic Lung Biopsy: Comparison Between C-Arm Cone-Beam CT and Conventional CT Guidance

BACKGROUND: C-arm cone-beam computed tomography (CBCT) is a comparatively novel modality for guiding percutaneous transthoracic lung biopsies (PTLBs), and despite its potential advantages over conventional computed tomography (CCT), a head-to-head comparison of the two techniques has yet to be reported in the literature. This study aims to evaluate the diagnostic value and safety of CBCT-guided PTLB compared to CCT-guided biopsy, with cases performed in a single hospital. METHODS: A total of 104 PTLB patients were retrospectively analyzed in this study. 35 PTLBs were performed under CBCT guidance, and 69 PTLBs were performed under CCT guidance. Diagnostic accuracy, sensitivity, and specificity for malignancy as well as procedure time, radiation dose of patients, and complication rate in the two groups were compared. RESULTS: Total procedure time was significantly lower in the CBCT group (32 ± 11 minutes) compared to the CCT group (38 ± 9.7 minutes; P = .009), especially among patients ≥ 70 years of age (CBCT: 33 ± 12 minutes, CCT: 42 ± 13, P = .022). For lesions in the lower lobes, the CBCT-guided group received significantly reduced effective radiation dose (2.9 ± 1.6 mSv) than CCT-guided patients (3.7 ± 0.80; P = .042). Diagnostic accuracy, sensitivity, and specificity for malignancy were comparable between the two groups, as were post-biopsy complication rates. CONCLUSION: CBCT guidance significantly reduces the procedure time and radiation exposure for PTLBs compared with CCT, and should be considered in clinical settings that may be difficult or time-consuming to perform under CCT.

Comparison of cone-beam CT-guided and CT fluoroscopy-guided transthoracic needle biopsy of lung nodules

PURPOSE

To compare the diagnostic performance of cone-beam CT (CBCT)-guided and CT fluoroscopy (fluoro-CT)-guided technique for transthoracic needle biopsy (TNB) of lung nodules.

METHODS

The hospital records of 319 consecutive patients undergoing 324 TNBs of lung nodules in a single radiology unit in 2009-2013 were retrospectively evaluated. The newly introduced CBCT technology was used to biopsy 123 nodules; 201 nodules were biopsied by conventional fluoro-CT-guided technique. We assessed the performance of the two biopsy systems for diagnosis of malignancy and the radiation exposure.

RESULTS

Nodules biopsied by CBCT-guided and by fluoro-CT-guided technique had similar characteristics: size, 20 ± 6.5 mm (mean ± standard deviation) vs. 20 ± 6.8 mm (p = 0.845); depth from pleura, 15 ± 15 mm vs. 15 ± 16 mm (p = 0.595); malignant, 60% vs. 66% (p = 0.378). After a learning period, the newly introduced CBCT-guided biopsy system and the conventional fluoro-CT-guided system showed similar sensitivity (95% and 92%), specificity (100% and 100%), accuracy for diagnosis of malignancy (96% and 94%), and delivered non-significantly different median effective doses [11.1 mSv (95 % CI 8.9-16.0) vs. 14.5 mSv (95% CI 9.5-18.1); p = 0.330].

CONCLUSION

The CBCT-guided and fluoro-CT-guided systems for lung nodule biopsy are similar in terms of diagnostic performance and effective dose, and may be alternatively used to optimize the available technological resources.

KEY POINTS

• CBCT-guided and fluoro-CT-guided lung nodule biopsy provided high and similar diagnostic accuracy. • Effective dose from CBCT-guided and fluoro-CT-guided lung nodule biopsy was similar. • To optimize resources, CBCT-guided lung nodule biopsy may be an alternative to fluoro-CT-guided.

C-Arm Cone-Beam CT Virtual Navigation-Guided Percutaneous Mediastinal Mass Biopsy: Diagnostic Accuracy and Complications

OBJECTIVES

To assess the usefulness of C-arm cone-beam computed tomography (CBCT) virtual navigation-guided percutaneous mediastinal mass biopsy in terms of diagnostic accuracy and complication rates.

METHODS

Seventy-eight CBCT virtual navigation-guided percutaneous mediastinal mass biopsies were performed in 75 patients (M:F, 38:37; mean age, 48.55 ± 18.76 years). The procedural details, diagnostic sensitivity, specificity, accuracy and complication rate were investigated.

RESULTS

Mean lesion size was 6.80 ± 3.08 cm, skin-to-target distance was 3.67 ± 1.80 cm, core needle biopsy rate was 96.2 % (75/78), needle indwelling time was 9.29 ± 4.34 min, total procedure time was 13.26 ± 5.29 min, number of biopsy specimens obtained was 3.13 ± 1.02, number of CBCTs performed was 3.03 ± 0.68, rate of lesion border discrimination from abutting mediastinal structures on CBCT was 26.9 % (21/78), technical success rate was 100 % (78/78), estimated effective dose was 5.33 ± 4.99 mSv, and the dose area product was 12,723.68 ± 10,665.74 mGy⋅cm(2). Among the 78 biopsies, 69 were malignant, 7 were benign and 2 were indeterminate. Diagnostic sensitivity, specificity and accuracy for the diagnosis of malignancies were 97.1 % (67/69), 100 % (7/7) and 97.4 % (74/76), respectively, with a complication rate of 3.85 % (3/78), all of which were small pneumothoraces.

CONCLUSIONS

CBCT virtual navigation-guided biopsy is a highly accurate and safe procedure for the evaluation of mediastinal lesions.

KEY POINTS

• CBCT virtual navigation-guided percutaneous mediastinal biopsy is highly accurate • CBCT virtual navigation-guided percutaneous mediastinal biopsy is a safe procedure • Mediastinal vascular injury can be avoided under CBCT virtual navigation guidance.

Cone-Beam Computed Tomography (CBCT) Versus CT in Lung Ablation Procedure: Which is Faster?

AIM

To compare cone-beam CT (CBCT) versus computed tomography (CT) guidance in terms of time needed to target and place the radiofrequency ablation (RFA) electrode on lung tumours.

MATERIALS AND METHODS

Patients at our institution who received CBCT- or CT-guided RFA for primary or metastatic lung tumours were retrospectively included. Time required to target and place the RFA electrode within the lesion was registered and compared across the two groups. Lesions were stratified into three groups according to their size (<10, 10-20, >20 mm). Occurrences of electrode repositioning, repositioning time, RFA complications, and local recurrence after RFA were also reported.

RESULTS

Forty tumours (22 under CT, 18 under CBCT guidance) were treated in 27 patients (19 male, 8 female, median age 67.25 ± 9.13 years). Thirty RFA sessions (16 under CBCT and 14 under CT guidance) were performed. Multivariable linear regression analysis showed that CBCT was faster than CT to target and place the electrode within the tumour independently from its size (β = -9.45, t = -3.09, p = 0.004). Electrode repositioning was required in 10/22 (45.4 %) tumours under CT guidance and 5/18 (27.8 %) tumours under CBCT guidance. Pneumothoraces occurred in 6/14 (42.8 %) sessions under CT guidance and in 6/16 (37.5 %) sessions under CBCT guidance. Two recurrences were noted for tumours receiving CBCT-guided RFA (2/17, 11.7 %) and three after CT-guided RFA (3/19, 15.8 %).

CONCLUSION

CBCT with live 3D needle guidance is a useful technique for percutaneous lung ablation. Despite lesion size, CBCT allows faster lung RFA than CT.

Rapid needle-out patient-rollover approach after cone beam CT-guided lung biopsy: effect on pneumothorax rate in 1,191 consecutive patients

OBJECTIVES

To investigate the effect of rapid needle-out patient-rollover approach on the incidence of pneumothorax and drainage catheter placement due to pneumothorax in C-arm Cone-beam CT (CBCT)-guided percutaneous transthoracic needle biopsy (PTNB) of lung lesions.

METHODS

From May 2011 to December 2012, 1227 PTNBs were performed in 1191 patients with a 17-gauge coaxial needle. 617 biopsies were performed without (conventional-group) and 610 with rapid-rollover approach (rapid-rollover-group). Overall pneumothorax rates and incidences of pneumothorax requiring drainage catheter placement were compared between two groups.

RESULTS

There were no significant differences in overall pneumothorax rates between conventional and rapid-rollover groups (19.8% vs. 23.1%, p = 0.164). However, pneumothorax rate requiring drainage catheter placement was significantly lower in rapid-rollover-group (1.6%) than conventional-group (4.2%) (p = 0.010). Multivariate analysis revealed male, age > 60, bulla crossed, fissure crossed, pleura to target distance > 1.3 cm, emphysema along needle tract, and pleural punctures ≥ 2 were significant risk factors of pneumothorax (p < 0.05). Regarding pneumothorax requiring drainage catheter placement, fissure crossed, bulla crossed, and emphysema along needle tract were significant risk factors (p < 0.05), whereas rapid-rollover approach was an independent protective factor (p = 0.002).

CONCLUSIONS

The rapid needle-out patient-rollover approach significantly reduced the rate of pneumothorax requiring drainage catheter placement after CBCT-guided PTNB.

KEY POINTS

• The rapid-rollover approach had little beneficial effect on overall pneumothorax rate. • The rapid-rollover approach significantly reduced drainage catheter placement due to pneumothorax. • The strongest risk factor was pleural punctures ≥ 2 per procedure. • Emphysema along the needle tract was a stronger risk factor than fissure-crossed.

Flat-panel cone-beam CT-guided radiofrequency ablation of very small (≤ 1.5 cm) liver tumors: technical note on a preliminary experience

PURPOSE

The aim of the present study was to investigate the technical feasibility of flat-panel cone-beam CT (CBCT)-guided radiofrequency ablation (RFA) of very small (<1.5 cm) liver tumors.

MATERIALS AND METHODS

Patients included were candidates for hepatic percutaneous RFA as they had single biopsy-proven hepatic tumors sized ≤ 1.5 cm and poorly defined on ultrasonography. Following apnea induction, unenhanced CBCT scans were acquired and used to deploy the RF electrode with the aid of a virtual navigation system. If the tumor was not clearly identified on the unenhanced CBCT scan, a right retrograde arterial femoral access was established to carry out hepatic angiography and localize the tumor. Patients' lesions and procedural variables were recorded and analyzed.

RESULTS

Three patients (2 male and 1 female), aged 68, 76, and 87 years were included; 3 lesions (2 hepato-cellular carcinoma and 1 metastasis from colorectal cancer) were treated. One patient required hepatic angiography. Cycles of apnea used to acquire CBCT images and to deploy the electrode lasted <120 s. Mean fluoroscopic time needed to deploy the electrode was 36.6 ± 5.7 min. Mean overall procedural time was 66.0 ± 22.9 min. No peri- or post-procedural complications were noted. No cases of incomplete ablation were noted at 1-month follow-up.

CONCLUSION

Percutaneous CBCT-guided liver RFA with or without arterial hepatic angiography is technically feasible.

Patient reported experiences of CT guided lung biopsy: a prospective cohort study

Background

CT guided lung biopsy is a commonly performed procedure to obtain tissue for a histological diagnosis in cases of suspected lung cancer.

Methods

This is a prospective cohort study to obtain information directly from patients about their experiences of the biopsy procedure, thus obtaining a more accurate picture of complications compared with previously performed retrospective reviews. Patients participated in a post-procedure telephone interview and information was gathered about any procedural complications and personal experiences. We also compared the patient reported complications with those obtained from a retrospective review of hospital databases, analogous to previously performed retrospective studies.

Results

In our patient group, reported procedural complication rates were 10% pneumothorax rate (4% requiring a chest drain) and 10% haemoptysis. Post-procedural pain and shortness of breath showed positive correlation, with one patient experiencing prolonged pain. No statistical difference was found between the patient reported complication rates and those obtained from retrospective review of the hospital database.

Conclusions

Our study demonstrates CT guided lung biopsy is a safe procedure and is generally well tolerated. Some patients may experience significant and lasting pain and therefore should be counselled about this pre-procedure.

C-arm cone-beam computed tomography needle path overlay for percutaneous biopsy of pulmonary nodules

PURPOSE

The aim of this study was to evaluate the feasibility of percutaneous transthoracic needle biopsy of pulmonary nodules under cone-beam computed tomography (CBCT) with "XperGuide" navigation guidance.

MATERIALS AND METHODS

From February 2010 to January 2012, 100 patients (63 men and 37 women; mean age 67.27 years; range 21-88 years) with 100 lung nodules (44 ≤ 3 cm, 56 > 3 cm) underwent CBCT-XperGuide guided percutaneous transthoracic needle biopsies. Technical success, diagnostic accuracy, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and complications were evaluated.

RESULTS

Of 100 nodules (mean size 5.19 cm), 68 were diagnosed as malignant, 27 as benign, and five as indeterminate. Technical success was 95 %. Only 33 of 100 patients underwent surgery: the final pathological diagnosis was concordant with the biopsy diagnosis in 26 cases and discordant in 7 cases (false negatives). Accuracy, sensitivity, specificity, PPV and NPV were 92.6, 90.9, 100, 100 and 72 %, respectively.

CONCLUSIONS

CBCT-XperGuide navigation is a new, accurate and safe imaging guidance for percutaneous lung biopsies.

Target visibility enhancement for C-arm cone beam CT-fluoroscopy-guided hepatic needle placement: implementation and accuracy evaluation

PURPOSE

Fluoroscopy-guided hepatic intervention is limited by target visibility and respiratory movement. A feasible procedure for visibility enhancement of the key regions and targets in 2D fluoroscopic images is needed. A system was developed to improve targeting by integrating the forward projection of objects extracted from 3D cone beam CT (CBCT) volumes. The target matching accuracy during regular respiration was measured to evaluate the system.

METHOD

3D CBCT abdominal volumes were acquired and segmented to extract different regions, including the diaphragm, hepatic vessels, bony structures, and hepatic tumor. The segmented result was rendered and projected to generate augmented fluoroscopy fusion images. The target matching accuracy by applying these procedures was evaluated for the hepatic intervention guidance.

RESULT

Quantitative assessment of the target matching accuracy in the upper section of liver was performed for eight targets from four subjects. The 2D and 3D target matching accuracy were 0.98±0.37 and 1.47±0.26 mm, respectively. The 2D target matching accuracy was 1.46±0.67 mm for the target in the lower liver. This accuracy should be acceptable for the 5 mm safety margin required in clinical use.

CONCLUSION

Visibility of targets in 2D fluoroscopy was enhanced to improve interactive navigation guidance for hepatic needle placement. The target matching accuracy for the C-arm cone beam CT-fluoroscopy-guided hepatic needle targeting was sufficient for clinical use.

Percutaneous bone biopsies: comparison between flat-panel cone-beam CT and CT-scan guidance

PURPOSE

This study was designed to compare the accuracy of targeting and the radiation dose of bone biopsies performed either under fluoroscopic guidance using a cone-beam CT with real-time 3D image fusion software (FP-CBCT-guidance) or under conventional computed tomography guidance (CT-guidance).

METHODS

Sixty-eight consecutive patients with a bone lesion were prospectively included. The bone biopsies were scheduled under FP-CBCT-guidance or under CT-guidance according to operating room availability. Thirty-four patients underwent a bone biopsy under FP-CBCT and 34 under CT-guidance. We prospectively compared the two guidance modalities for their technical success, accuracy, puncture time, and pathological success rate. Patient and physician radiation doses also were compared.

RESULTS

All biopsies were technically successful, with both guidance modalities. Accuracy was significantly better using FP-CBCT-guidance (3 and 5 mm respectively: p = 0.003). There was no significant difference in puncture time (32 and 31 min respectively, p = 0.51) nor in pathological results (88 and 88 % of pathological success respectively, p = 1). Patient radiation doses were significantly lower with FP-CBCT (45 vs. 136 mSv, p < 0.0001). The percentage of operators who received a dose higher than 0.001 mSv (dosimeter detection dose threshold) was lower with FP-CBCT than CT-guidance (27 vs. 59 %, p = 0.01).

CONCLUSIONS

FP-CBCT-guidance for bone biopsy is accurate and reduces patient and operator radiation doses compared with CT-guidance.

C-arm cone-beam CT-guided percutaneous transthoracic needle biopsy of lung nodules: clinical experience in 1108 patients

PURPOSE

To retrospectively evaluate the diagnostic performance and complications of C-arm cone-beam computed tomography (CT)-guided percutaneous transthoracic needle biopsy (PTNB) in 1108 patients.

MATERIALS AND METHODS

This retrospective study was approved by the institutional review board with waiver of patient informed consent. From January 2009 to December 2011, 1108 patients (633 male, 475 female; mean age, 62.4 years ± 12.3 [standard deviation]) with 1116 pulmonary lesions (mean size, 2.7 cm ± 1.7) underwent 1153 cone-beam CT-guided PTNBs. A coaxial system with 18-gauge cutting needles was used. Diagnostic performance, complication rate, influencing factors, and patient radiation exposure were investigated. Variables influencing diagnostic performance and complications were assessed by using uni- and multivariate logistic regression analyses.

RESULTS

Among 1153 PTNBs, pathologic analysis showed 1148 (99.6%) were technically successful (766 malignant [66.4%], 323 benign [28.0%], and 59 [5.1%] indeterminate). Sensitivity, specificity, and accuracy for diagnosis of malignancy were 95.7% (733 of 766), 100% (323 of 323), and 97.0% (1056 of 1089), respectively. In regard to diagnostic failures (five technical failures, 33 false-negative findings), lesions 1 cm in diameter or smaller and lesions in the lower lobe were significant risk factors (P = .028 and P = .034, respectively). As for complications, pneumothorax and hemoptysis occurred in 196 (17.0%) and 80 (6.9%) procedures, respectively. Multivariate analysis revealed two or more pleural passages and emphysema along the needle pathway were the two most significant risk factors for pneumothorax, and ground-glass nodules were the most significant risk factor for hemoptysis (P < .001 for all). Virtual guidance was a significant protective factor for both pneumothorax and hemoptysis (P < .001 for both). Mean estimated effective radiation dose through cone-beam CT-guided PTNBs was 7.3 mSv ± 4.1.

CONCLUSION

Cone-beam CT-guided PTNB is a highly accurate and safe technique with which to diagnose pulmonary lesions with reasonable radiation exposure.

C-arm Cone Beam Computed Tomography: A New Tool in the Interventional Suite

Introduction: C-arm Cone Beam CT (CBCT) is a technology that is being integrated into many of the newer angiography systems in the interventional suite. Due to its ability to provide cross sectional imaging, it has opened a myriad of opportunities for creating new clinical applications. We review the technical aspects, current reported clinical applications and potential benefits of this technology. Materials and Methods: Searches were made via PubMed using the string “CBCT”, “Cone Beam CT”, “Cone Beam Computed Tomography” and “C-arm Cone Beam Computed Tomography”. All relevant articles in the results were reviewed. Results: CBCT clinical applications have been reported in both vascular and non-vascular interventions. They encompass many aspects of a procedure including preprocedural planning, intraprocedural guidance and postprocedural assessment. As a result, they have allowed the interventionalist to be safer and more accurate in performing image guided procedures. There are however several technical limitations. The quality of images produced is not comparable to conventional computed tomography (CT). Radiation doses are also difficult to quantify when compared to CT and fluoroscopy. Conclusion: CBCT technology in the interventional suite has contributed significant benefits to the patient despite its current limitations. It is a tool that will evolve and potentially become an integral part of imaging guidance for intervention. Key words: Angiogram, Biopsy, Embolisation, Intervention, Stenting, Vascular

Percutaneous transthoracic needle biopsy of small (≤ 1 cm) lung nodules under C-arm cone-beam CT virtual navigation guidance

OBJECTIVES

To describe our initial experience with percutaneous transthoracic needle biopsy (PCNB) of small (≤1 cm) lung nodules using a cone-beam computed tomography (CBCT) virtual navigation guidance system in 105 consecutive patients.

METHODS

One hundred and five consecutive patients (55 male, 50 female; mean age, 62 years) with 107 small (≤1 cm) lung nodules (mean size, 0.85 cm ± 0.14) underwent PCNBs under CBCT virtual-navigation guidance system and constituted our study population. Procedural details-including radiation dose, sensitivity, specificity, diagnostic accuracy and complication rates of CBCT virtual navigation guided PCNBs-were described.

RESULTS

The mean number of pleural passages with the coaxial needle, biopsies, CT acquisitions, total procedure time, coaxial introducer dwelling time, and estimated radiation exposure during PCNBs were 1.03 ± 0.21, 3.1 ± 0.7, 3.4 ± 1.3, 10.5 min ± 3.2 and 7.2 min ± 2.5, and 5.72 mSv ± 4.19, respectively. Sixty nodules (56.1 %) were diagnosed as malignant, 38 (35.5 %) as benign and nine (8.4 %) as indeterminate. The sensitivity, specificity, and diagnostic accuracy of CBCT virtual-navigation-guided PCNB for small (≤1 cm) nodules were 96.7 % (58/60), 100 % (38/38) and 98.0 % (96/98), respectively. Complications occurred in 13 (12.1 %) cases; pneumothorax in seven (6.5 %) and haemoptysis in six (5.6 %).

CONCLUSION

CBCT virtual-navigation-guided PCNB is a highly accurate and safe diagnostic method for small (≤1 cm) nodules.

Effect of cerium on drug metabolizing activity in rat liver

Objectives

To meta-analyze complication rate in computed tomography (CT)-guided transthoracic lung biopsy and associated risk factors.

Methods

Four databases were searched from 1/2000 to 8/2015 for studies reporting complications in CT-guided lung biopsy. Overall and major complication rates were pooled and compared between core biopsy and fine needle aspiration (FNA) using the random-effects model. Risk factors for complications in core biopsy and FNA were identified in meta-regression analysis.

Results

For core biopsy, 32 articles (8,133 procedures) were included and for FNA, 17 (4,620 procedures). Pooled overall complication rates for core biopsy and FNA were 38.8 % (95 % CI: 34.3–43.5 %) and 24.0 % (95 % CI: 18.2–30.8 %), respectively. Major complication rates were 5.7 % (95 % CI: 4.4–7.4 %) and 4.4 % (95 % CI: 2.7–7.0 %), respectively. Overall complication rate was higher for core biopsy compared to FNA (p < 0.001). For FNA, larger needle diameter was a risk factor for overall complications, and increased traversed lung parenchyma and smaller lesion size were risk factors for major complications. For core biopsy, no significant risk factors were identified.

Conclusions

In CT-guided lung biopsy, minor complications were common and occurred more often in core biopsy than FNA. Major complication rate was low. For FNA, smaller nodule diameter, larger needle diameter and increased traversed lung parenchyma were risk factors for complications.

Key Points

• Minor complications are common in CT-guided lung biopsy

• Major complication rate is low in CT-guided lung biopsy

• CT-guided lung biopsy complications occur more often in core biopsy than FNA

• Major complication rate is similar in core biopsy and FNA

• Risk factors for FNA are larger needle diameter, smaller lesion size

Electronic supplementary material

The online version of this article (doi:10.1007/s00330-016-4357-8) contains supplementary material, which is available to authorized users.