CT fluoroscopy-guided lung biopsy versus conventional CT-guided lung biopsy: a prospective controlled study to assess radiation doses and diagnostic performance

Percutaneous Lung Biopsies With Robotic Systems: A Systematic Review of Available Clinical Solutions

Objectives: This systematic review aims to assess existing research concerning the use of robotic systems to execute percutaneous lung biopsy. Methods: A systematic review was performed and identified 4 studies involving robotic systems used for lung biopsy. Outcomes assessed were operation time, radiation dose to patients and operators, technical success rate, diagnostic yield, and complication rate. Results: One hundred and thirteen robot-guided percutaneous lung biopsies were included. Technical success and diagnostic yield were close to 100%, comparable to manual procedures. Technical accuracy, illustrated by needle positioning, showed less frequent needle adjustments in robotic guidance than in manual guidance (P < .001): 2.7 ± 2.6 (range 1-4) versus 6 ± 4 (range 2-12). Procedure time ranged from comparable to reduced by 35% on average (20.1 ± 11.3 minutes vs 31.4 ± 10.2 minutes, P = .001) compared to manual procedures. Patient irradiation ranged from comparable to reduced by an average of 40% (324 ± 114.5 mGy vs 541.2 ± 446.8 mGy, P = .001). There was no significant difference in reported complications between manual biopsy and biopsies that utilized robotic guidance. Conclusion: Robotic systems demonstrate promising results for percutaneous lung biopsy. These devices provide adequate accuracy in probe placement and could both reduce procedural duration and mitigate radiation exposure to patients and practitioners. However, this review underscores the need for larger, controlled trials to validate and extend these findings.

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.

An Interventional Radiologist's Guide to Lung Cancer

Lung cancer continues to be the third leading cause of cancer and the leading cause of cancer deaths. As the field of interventional oncology continues to grow, interventional radiologists are increasingly treating lung cancer patients. Involvement begins with tissue diagnosis for which biomarkers and immunohistochemistry are used to guide selective and advanced medical therapies. An interventional radiologist must be aware of the rationale behind tissue diagnosis and techniques to minimize biopsy complications. Staging is an important part of tumor board conversations and drives treatment pathways. Surgical therapy remains the gold standard for early-stage disease but with an aging population the need for less invasive treatments such as radiation therapy and ablation continue to grow. The interventionalist must be aware of the indications, techniques, and pre- and posttherapy managements for percutaneous ablation. Endovascular therapy is broadly divided into therapeutic treatment of lung cancer, which is gaining traction, and treatment of lung cancer complications such as hemoptysis. This review aims to provide a good basis for interventional radiologists treating lung cancer patients.

Patient Dose Estimation in Computed Tomography-Guided Biopsy Procedures

This study establishes typical Diagnostic Reference Levels (DRL) values and assesses patient doses in computed tomography (CT)-guided biopsy procedures. The Effective Dose (ED), Entrance Skin Dose (ESD), and Size-Specific Dose Estimate (SSDE) were calculated using the relevant literature-derived conversion factors. A retrospective analysis of 226 CT-guided biopsies across five categories (Iliac bone, liver, lung, mediastinum, and para-aortic lymph nodes) was conducted. Typical DRL values were computed as median distributions, following guidelines from the International Commission on Radiological Protection (ICRP) Publication 135. DRLs for helical mode CT acquisitions were set at 9.7 mGy for Iliac bone, 8.9 mGy for liver, 8.8 mGy for lung, 7.9 mGy for mediastinal mass, and 9 mGy for para-aortic lymph nodes biopsies. In contrast, DRLs for biopsy acquisitions were 7.3 mGy, 7.7 mGy, 5.6 mGy, 5.6 mGy, and 7.4 mGy, respectively. Median SSDE values varied from 7.6 mGy to 10 mGy for biopsy acquisitions and from 11.3 mGy to 12.6 mGy for helical scans. Median ED values ranged from 1.6 mSv to 5.7 mSv for biopsy scans and from 3.9 mSv to 9.3 mSv for helical scans. The study highlights the significance of using DRLs for optimizing CT-guided biopsy procedures, revealing notable variations in radiation exposure between helical scans covering entire anatomical regions and localized biopsy acquisitions.

Ultrasound-guided core-needle biopsy for peripheral pulmonary lesions: a systematic review and meta-analysis

AIM

To evaluate the diagnostic value and safety of ultrasound-guided core-needle biopsy for peripheral pulmonary lesions (PPLs).

MATERIALS AND METHODS

PubMed, EMBASE, and the Cochrane Library for relevant were searched for studies published up to June 2022. The diagnostic accuracy of US-guided percutaneous transthoracic needle biopsy (PTNB) for the diagnosis of PPLs was evaluated using pooled sensitivity, specificity, diagnostic odds ratio (DOR), positive and negative likelihood ratios (PLR and NLR), and the area under the summary receiver operating characteristic curves value (SROC).

RESULTS

The search included 12 original studies (3,830 procedures). For US-guided PTNB, the pooled sensitivity and specificity for the diagnosis of PPLs were 0.93 (95% confidence interval [CI]: 0.91-0.94) and 0.99 (95% CI: 0.96-1.00), respectively. The pooled estimates of the PLR, NLR, and DOR were 134.88 (95% CI: 24.88-731.74), 0.07 (95% CI: 0.06-0.09), and 1,814.95 (95% CI: 333.62-9,873.76), respectively. The area under the SROC curve was 0.95 (95% CI: 0.93-0.97). The overall complication rate was 3.6% (136 of 3,830), including self-limited haemoptysis and asymptomatic pneumothorax, and only six cases of pneumothorax requiring chest tube drainage and one case of severe bleeding were reported.

CONCLUSIONS

US-guided core-needle biopsy is an excellent diagnostic tool for PPLs, with high accuracy and excellent technical performance and safety.

CT Navigation for Percutaneous Needle Placement: How I Do It

CT navigation (CTN) has recently been developed to combine many of the advantages of conventional CT and CT-fluoroscopic guidance for needle placement. CTN systems display real-time needle position superimposed on a CT dataset. This is accomplished by placing electromagnetic (EM) or optical transmitters/sensors on the patient and needle, combined with fiducials placed within the scan field to superimpose a known needle location onto a CT dataset. Advantages of CTN include real-time needle tracking using a contemporaneous CT dataset with the patient in the treatment position, reduced radiation to the physician, facilitation of procedures outside the gantry plane, fewer helical scans during needle placement, and needle guidance based on diagnostic-quality CT datasets. Limitations include the display of a virtual (vs actual) needle position, which can be inaccurate if the needle bends, the fiducial moves, or patient movement occurs between scans, and limitations in anatomical regions with a high degree of motion such as the lung bases. This review summarizes recently introduced CTN technologies in comparison to historical methods of CT needle guidance. A "How I do it" section follows, which describes how CT navigation has been integrated into the study center for both routine and challenging procedures, and includes step-by-step explanations, technical tips, and pitfalls.

Dose length product and outcome of CT fluoroscopy-guided interventions using a new 320-detector row CT scanner with deep-learning reconstruction and new bow-tie filter

OBJECTIVES

To investigate the dose length product (DLP) and outcomes of CT fluoroscopy (CTF)-guided interventions using a novel 320-detector row CT scanner with deep-learning reconstruction (DLR) and a new bow-tie filter (i.e., Aquilion ONE Prism Edition) and compare with a 320-detector row CT system without DLR and the new bow-tie filter (i.e., Aquilion ONE Vision Edition) (Vision).

METHODS

CTF-guided interventions performed using Prism and Vision were retrospectively investigated in terms of the technical success rates, clinical success rates of biopsies, complications, DLPs of total CT scans (total DLPs) from February 2019 to January 2021. The total CT scans included pre-interventional CT scans, CTF scans during the CTF-guided procedure, additional CT scans for additional treatment, CTF scans for additional treatment, and post-interventional CT scans.

RESULTS

In this study, 87 and 85 CTF-guided interventions were performed using Vision (Vision group) and Prism (Prism group), respectively. There was no significant difference in the technical success rate (96.6% vs 98.8%, p = 0.621), clinical success rate of biopsies (92.9% vs 93.4%, p = 1.000), and minor (8.0% vs 7.1%, p = 0.807) and major (0% vs 3.5%, p = 0.119) complications between the Prism and Vision groups. The total DLPs for the Prism group were significantly lower than those for the Vision group regardless of the procedure (278 vs 548 mGy*cm, p < 0.001, in the biopsy and 246 vs 667 mGy*cm, p < 0.001, in the drainage and aspiration).

CONCLUSIONS

CTF-guided interventions on Prism reduce the total DLP without performance degradation of the intervention.

ADVANCES IN KNOWLEDGE

The total DLPs of biopsies and drainages/aspirations in the Prism group decreased by 49 and 63%, respectively.

Radiation Exposure and Protection in Computed Tomography Fluoroscopy

Computed tomography (CT) fluoroscopy-guided procedures, such as those used for percutaneous biopsy, drainage, and radiofrequency ablation, are highly safe and quite often very successful due to the precision offered by the real-time, high-resolution tomographic images. Even so, international guidelines raised concerns regarding operator exposure to high doses of radiation during these procedures. In light of these concerns, operators conducting CT fluoroscopy-guided procedures not only need to be cognizant of the exposure risk but also exhibit sufficient knowledge of radiation protection. This paper reviews the current literature on experimental and clinical studies of radiation exposure doses to operators during CT fluoroscopy-guided procedures. In addition to the literature review, this paper also introduces different approaches that can be implemented to ensure appropriate radiation protection.

Comparison between Image-Guided Transbronchial Cryobiopsies and Thoracoscopic Lung Biopsies in Canine Cadaver: A Pilot Study

Simple Summary

A definitive diagnosis for most pulmonary diseases is possible only through histopathological examination. The literature describes different methods of lung biopsy sampling depending on the case. However, for the diagnosis of diffuse interstitial pulmonary diseases and some peripheral neoplasms, the gold standard is represented by surgical lung biopsies. Given their invasiveness and the high percentage of risk for the patient, in most cases they are not carried out, resulting in a serious diagnostic gap. In human medicine, transbronchial lung cryobiopsies have been introduced as an alternative, which have shown high efficacy and reduced invasiveness. This study aims to evaluate the feasibility of the new technique in dogs by subjecting dog cadavers to pulmonary cryobiopsy and surgical lung biopsies, and to compare the samples obtained for histopathological quality. In total, 42 tissue samples were compared. Pulmonary cryobiopsies were smaller than surgical biopsies but with high levels of agreement upon histological evaluation. This study demonstrates the feasibility of the technique in dogs and the collection of specimens with size and histological features comparable to those from surgical biopsies.

Abstract

To date, the only method of sampling lung tissue with a high diagnostic yield is represented by surgical lung biopsies (SLB), which are highly invasive and have a high risk/benefit ratio. In humans, transbronchial lung cryobiopsies (TBLC) have recently been introduced, which are described to be less invasive and able to significantly increase diagnostic confidence in most patients with interstitial lung diseases. The aim of this study was to evaluate the feasibility and diagnostic yield of TBLC compared to SLB in small animals. A total of 21 pulmonary cryobiopsies under fluoroscopic and real-time CT fluoroscopic guidance and 21 video-assisted thoracoscopic surgery (VATS) lung biopsies were collected from three dog cadavers. Upon histological examination, cryobiopsy samples were smaller than VATS biopsies, but were still large enough to reach a specific diagnosis or to allow pattern recognition. Morphological features on TBLC and SLB were concordant in all cases. Cryobiopsy samples showed fewer artifacts and a higher percentage of alveolar tissue than VATS samples. TBLC is a feasible and useful alternative to SLB for lung histopathological examination in dogs. The effectiveness and reduced invasiveness of TBLC compared to SLB could represent many advantages in the diagnosis of diffuse lung diseases in small animals.

Percutaneous transthoracic needle biopsies in immunocompromised hosts with suspicious pulmonary infection: diagnostic yields and complications

BACKGROUND

Pulmonary infection is a major cause of morbidity and mortality in immunocompromised patients, in whom diagnostic yields of cone-beam computed tomography (CBCT)-guided percutaneous transthoracic needle biopsies (PTNBs) have not been evaluated so far.

PURPOSE

To evaluate diagnostic yields and complications of CBCT-guided PTNBs in immunocompromised patients.

MATERIAL AND METHODS

From January 2015 to January 2018, 43 patients (25 men, 18 women; mean age 54.1 ± 16.4 years) who were suspected of having pulmonary infections were included in this retrospective study. Electronic medical records and radiologic studies were reviewed, including the underlying medical status, information on target lesions, PTNB procedural factors, and pathologic results. Logistic regression was performed to explore factors related with post-PTNB complications.

RESULTS

Among 43 patients, specific causative organisms or family of organisms were identified by PTNBs in 16 patients (37.2%). The most common causative organism was fungus (10/16, 62.5%), while bacterial infection was pathologically proven only in one patient (6.3%). Clinically significant change in management occurred in 12 of 43 patients (27.9%). Post-PTNB complications developed in 12 patients (27.9%; pneumothorax [n = 6] and hemoptysis [n = 6]) without PTNB-related mortality. Lower lobar location (odds ratio [OR] = 0.07, P = 0.006) was related with post-PTNB pneumothorax, while lower platelet counts (≤127 × 10³/µL) were associated with post-PTNB hemoptysis (OR = 9.82, P = 0.025).

CONCLUSION

CBCT-guided PTNBs revealed microbiological pathogens in 37.2% of immunocompromised patients and led to subsequent clinical actions in 27.9% of patients. Post-PTNB complications occurred in 27.9% of patients, and it might be necessary to perform PTNBs more carefully in immunocompromised patients with lower platelet counts.

Comparison between computed tomography-guided core and fine needle lung biopsy: A meta-analysis

BACKGROUND

This meta-analysis was conducted to compare the safety and diagnostic performance between computed tomography (CT)-guided core needle biopsy (CNB) and fine-needle aspiration biopsy (FNAB) in lung nodules/masses patients.

METHODS

All relevant studies in the Pubmed, Embase, and Cochrane Library databases that were published as of June 2020 were identified. RevMan version 5.3 was used for all data analyses.

RESULTS

In total, 9 relevant studies were included in the present meta-analysis. These studies were all retrospective and analyzed outcomes associated with 2175 procedures, including both CT-guided CNB (n = 819) and FNAB (n = 1356) procedures. CNB was associated with significantly higher sample adequacy rates than was FNAB (95.7% vs 85.8%, OR: 0.26; P < .00001), while diagnostic accuracy rates did not differ between these groups (90.1% vs 87.6%, OR: 0.8; P = .46). In addition, no differences in rates of pneumothorax (28.6% vs 23.0%, OR: 1.15; P = .71), hemorrhage (17.3% vs 20.1%, OR: 0.91; P = .62), and chest tube insertion (5.9% vs 4.9%, OR: 1.01; P = .97) were detected between these groups. Significant heterogeneity among included studies was detected for the diagnostic accuracy (I2 = 57%) and pneumothorax (I2 = 77%) endpoints. There were no significant differences between CNB and FNAB with respect to diagnostic accuracy rates for lung nodules (P = .90). In addition, we detected no evidence of significant publication bias.

CONCLUSIONS

CT-guided CNB could achieve better sample adequacy than FNAB did during the lung biopsy procedure. However, the CNB did not show any superiorities in items of diagnostic accuracy and safety.

Radiation Eye Dose for Physicians in CT Fluoroscopy-Guided Biopsy

It is important to evaluate the radiation eye dose (3 mm dose equivalent, Hp (3)) received by physicians during computed tomography fluoroscopy (CTF)-guided biopsy, as physicians are close to the source of scattered radiation. In this study, we measured the radiation eye dose in Hp (3) received by one physician during CTF in a timeframe of 18 months using a direct eye dosimeter, the DOSIRIS^TM. The physician placed eye dosimeters above and under their lead (Pb) eyeglasses. We recorded the occupational radiation dose received using a neck dosimeter, gathered CT dose-related parameters (e.g., CT-fluoroscopic acquisition number, CT-fluoroscopic time, and CT-fluoroscopic mAs), and performed a total of 95 procedures during CTF-guided biopsies. We also estimated the eye dose (Hp (3)) received using neck personal dosimeters and CT dose-related parameters. The physician eye doses (right and left side) received in terms of Hp (3) without the use of Pb eyeglasses for 18 months were 2.25 and 2.06 mSv, respectively. The protective effect of the Pb eyeglasses (0.5 mm Pb) on the right and left sides during CTF procedures was 27.8 and 37.5%, respectively. This study proved the existence of significant correlations between the eye and neck dose measurement (right and left sides, R² = 0.82 and R² = 0.55, respectively) in physicians. In addition, we found significant correlations between CT-related parameters, such as CT-fluoroscopy mAs, and radiation eye doses (right and left sides, R² = 0.50 and R² = 0.52, respectively). The eye dose of Hp (3) received in CTF was underestimated when evaluated using neck dosimeters. Therefore, we suggest that the physician involved in CTF use a direct eye dosimeter such as the DOSIRIS for the accurate evaluation of their eye lens dose.

CT fluoroscopy-guided biopsy of pulmonary lesions contacting the interlobar fissure: An analysis of 72 biopsies

PURPOSE

The purpose of this study was to evaluate retrospectively the safety and diagnostic yield of computed tomography (CT) fluoroscopy-guided biopsy for pulmonary lesions with interlobar fissure contact.

MATERIALS AND METHODS

Seventy-two lesions showing interlobar fissure contact (mean size, 15.2 ± 5.3 [SD] mm [range: 5.3-27.0 mm]; mean length of interlobar fissure contact, 8.9 ± 3.6 [SD] mm [range: 2.6-17.5 mm] in 72 patients (33 men, 39 women; mean age, 69.7 ± 10.3 [SD] years; age range: 37-91 years) were evaluated. Multiple variables were assessed to determine the risk factors for diagnostic failure and pneumothorax. Additionally, these variables were compared between these 72 lesions and randomly selected controls (i.e., non-contact lesions).

RESULTS

All biopsies were technically successful using the transfissural (n = 14) or conventional routes (the route into the lung lobe with the target) with (n = 35) or without (n = 23) possible risk of needle insertion into the interlobar fissure after penetrating the target lesion. Sixty-eight (94.4%) procedures succeeded diagnostically and four (5.6%) failed. There were 27 grade I pneumothorax (37.5%), one (1.4%) grade II bleeding, and five (6.9%) grade IIIa pneumothorax requiring chest tube placement. Groups with and without pneumothorax did not differ significantly in patient-, lesion-, or procedure-related variables. Diagnostic yields and pneumothorax occurrence showed no significant differences between lesions with interlobar fissure contact and controls.

CONCLUSION

CT fluoroscopy-guided biopsy of pulmonary lesions with interlobar fissure contact is a safe procedure with a high diagnostic yield. Furthermore, because of potential complications, the transfissural route should be used only when a safer route is not possible.

Computed Tomography-guided Lung Biopsy: A Review of Techniques for Reducing the Incidence of Complications

Computed tomography-guided lung biopsy is a well-established method for the histological diagnosis of pulmonary lesions. There is abundant literature regarding the diagnostic yield of and complications associated with computed tomography-guided lung biopsy. Many studies have investigated the risk factors influencing pneumothorax. Conversely, there are a limited number of reports detailing techniques for reducing the incidence of pneumothorax or other complications. This study reviews the indications, diagnostic accuracy, and complications of computed tomography-guided lung biopsy. In addition, techniques for reducing the incidence of these complications were reviewed.

Reducing Time and Patient Radiation of Computed Tomography-guided Thoracic Needle Biopsies With Single-rotation Axial Acquisitions: An Alternative to "CT Fluoroscopy"

PURPOSE

To investigate the effect on procedure time and patient radiation indices of replacing helical acquisitions for needle guidance during thoracic needle biopsy (TNB) with intermittent single-rotation axial acquisitions.

MATERIALS AND METHODS

This retrospective intervention study included 215 consecutive TNBs performed by a single operator from 2014 to 2018. Characteristics of patients, lesions, and procedures were compared between TNBs guided only by helical acquisitions initiated in the control room (helical group, n=141) and TNBs guided in part by intermittent single-rotation axial computed tomography controlled by foot pedal (single-rotation group, n=74). Procedure time and patient radiation indices were primary outcomes, complications, and radiologist radiation dose were secondary outcomes.

RESULTS

Patient, lesion, and procedural characteristics did not differ between helical and single-rotation groups. Use of single-rotation axial acquisitions decreased procedure time by 10.5 minutes (95% confidence interval [CI]: 8.2-12.8 min) or 27% (95% CI: 22%-32%; P<0.001). Patient dose in cumulative volume computed tomography dose index decreased by 23% (95% CI: 12%-33%) or 8 mGy (95% CI: 4.3-31.6 mGy; P=0.01). Dose-length product decreased by 50% (95% CI: 40%-60%) or 270 mGy cm (95% CI: 195-345 mGy cm; P<0.001). No operator radiation exposure was detected. Rate of diagnostic result, pneumothorax, hemoptysis, and hemorrhage did not differ between groups.

CONCLUSIONS

Replacing helical acquisitions with intermittent single-rotation axial acquisitions significantly decreases TNB procedure time and patient radiation indices without adversely affecting diagnostic rate, procedural complications, or operator radiation dose.

Evaluation of CT-Guided Ultra-Low-Dose Protocol for Injection Guidance in Preparation of MR-Arthrography of the Shoulder and Hip Joints in Comparison to Conventional and Low-Dose Protocols

To evaluate patients’ radiation exposure undergoing CT-guided joint injection in preparation of MR-arthrography. We developed a novel ultra-low-dose protocol utilizing tin-filtration, performed it in 60 patients and compared the radiation exposure (DLP) and success rate to conventional protocol (26 cases) and low-dose protocol (37 cases). We evaluated 123 patients’ radiation exposure undergoing CT-guided joint injection from 16 January–21 March. A total of 55 patients received CT-guided joint injections with various other examination protocols and were excluded from further investigation. In total, 56 patients received shoulder injection and 67 received hip injection with consecutive MR arthrography. The ultra-low-dose protocol was performed in 60 patients, the low-dose protocol in 37 patients and the conventional protocol in 26 patients. We compared the dose of the interventional scans for each protocol (DLP) and then evaluated success rate with MR-arthrography images as gold standard of intraarticular or extracapsular contrast injection. There were significant differences when comparing the DLP of the ultra-low-dose protocol (DLP 1.1 ± 0.39; p < 0.01) to the low dose protocol (DLP 5.3 ± 3.24; p < 0.01) as well as against the conventional protocol (DLP 22.9 ± 8.66; p < 0.01). The ultra-low-dose protocol exposed the patients to an average effective dose of 0.016 millisievert and resulted in a successful joint injection in all 60 patients. The low dose protocol as well as the conventional protocol were also successful in all patients. The presented ultra-low-dose CT-guided joint injection protocol for the preparation of MR-arthrography demonstrated to reduce patients’ radiation dose in a way that it was less than the equivalent of the natural radiation exposure in Germany over 3 days—and thereby, negligible to the patient.

Computed Tomography-Navigation™ Electromagnetic System Compared to Conventional Computed Tomography Guidance for Percutaneous Lung Biopsy: A Single-Center Experience

The aim of our study was to assess the efficacy of a computed tomography (CT)-Navigation™ electromagnetic system compared to conventional CT methods for percutaneous lung biopsies (PLB). In this single-center retrospective study, data of a CT-Navigation™ system guided PLB (NAV-group) and conventional CT PLB (CT-group) performed between January 2017 and February 2020 were reviewed. The primary endpoint was the diagnostic success. Secondary endpoints were technical success, total procedure duration, number of CT acquisitions and the dose length product (DLP) during step ∆1 (from planning to initial needle placement), step ∆2 (progression to target), and the entire intervention (from planning to final control) and complications. Additional parameters were recorded, such as the lesion’s size and trajectory angles. Sixty patients were included in each group. The lesions median size and median values of the two trajectory angles were significantly lower (20 vs. 29.5 mm, p = 0.006) and higher in the NAV-group (15.5° and 10° vs. 6° and 1°; p < 0.01), respectively. Technical and diagnostic success rates were similar in both groups, respectively 95% and 93.3% in the NAV-group, and 93.3% and 91.6% in the CT-group. There was no significant difference in total procedure duration (p = 0.487) and total number of CT acquisitions (p = 0.066), but the DLP was significantly lower in the NAV-group (p < 0.01). There was no significant difference in complication rate. For PLB, CT-Navigation™ system is efficient and safe as compared to the conventional CT method.

Percutaneous Lung Biopsy with Pleural and Parenchymal Blood Patching: Results and Complications from 1,112 Core Biopsies

PURPOSE

To evaluate the outcomes of computed tomography (CT) fluoroscopy-guided core lung biopsies with emphasis on diagnostic yield, complications, and efficacy of parenchymal and pleural blood patching to avoid chest tube placement.

METHODS

This is a single-center retrospective analysis of CT fluoroscopy-guided percutaneous core lung biopsies between 2006 and 2020. Parenchymal blood patching during introducer needle withdrawal was performed in 74% of cases as a preventive measure, and pleural blood patching was the primary salvage maneuver for symptomatic or growing pneumothorax in 60 of 83 (72.2%) applicable cases.

RESULTS

A total of 1,029 patients underwent 1,112 biopsies (532 men; mean age, 66 years; 38.6%, history of emphysema; lesion size, 16.7 mm). The diagnostic yield was 93.6% (1,032/1,103). Fewer complications requiring intervention were observed in patients who underwent parenchymal blood patching (5.7% vs 14.2%, P < .001). Further intervention was required in 83 of 182 pneumothorax cases, which included the following: (a) pleural blood patch (5.4%, 60/1,112), (b) chest tube placement without a pleural blood patch attempt (1.5%, 17/1,112), and (c) simple aspiration (0.5%, 6/1,112). Pleural blood patch as monotherapy was successful in 83.3% (50/60) of cases without need for further intervention. The overall chest tube rate was 2.6% (29/1,112). Emphysema was the only significant risk factor for complications requiring intervention (P ≤ .001).

CONCLUSIONS

Parenchymal blood patching during introducer needle withdrawal decreased complications requiring intervention. Salvage pleural blood patching reduced the frequency of chest tube placement for pneumothorax.

Computed tomography guided lung biopsy under general anaesthesia with apnoea: Preliminary experience

Certain pulmonary lesions may be challenging to biopsy with conventional computed tomography percutaneous lung biopsy (CTPLB) under local anaesthesia (LA) which requires consistent patient breath holding to minimise complications. We aim to describe and evaluate the feasibility of CTPLB under general anaesthesia (GA) with apnoea, comparing results to patients undergoing biopsy under LA. This was a retrospective analysis of CTPLB with 18 GA and 137 LA patients. All biopsies were performed using a co-axial needle system in the radiology department on a multi-detector CT scanner with patient positioning determined by assessing shortest distance to target lesion. GA cases were performed under relaxant anaesthesia with intermittent positive pressure ventilation. Lower lobar lesion location and a combination of size and location (including proximity to critical structures) were indications for GA biopsy in >90% of patients. Mean lesion size for GA biopsies was 18 mm and control group 30 mm (P < 0.006) and mean pleura to lesion distance 29 and 11 mm, respectively (P < 0.0009). Pneumothorax rates were lower in our GA biopsy group (11%) compared to control group (42%) (P < 0.05). No anaesthetic complications were encountered. All GA samples were diagnostic. Based on a small number of patients, CTPLB under GA with apnoea seems a safe, feasible alternative to conventional CTPLB under LA for technically challenging lesions. This technique is routinely employed at our centre allowing access to lesions previously deemed unsafe to biopsy.

Computed tomography-guided core needle biopsy for lung nodules: low-dose versus standard-dose protocols

Introduction

Computed tomography (CT)-guided core needle biopsy (CNB) is an essential step in the management of lung nodules (LNs). Low-dose CT (LDCT)-guided CNB has been used to decrease the radiation exposure.

Aim

To evaluate the technical success, safety, diagnostic capacity, and radiation exposure to patients between LDCT-guided and standard-dose CT (SDCT)-guided CNB for LNs.

Material and methods

This is a retrospective, single-centre study. Patients who underwent LDCT-guided or SDCT-guided CNB for LNs from January 2015 to December 2017 were included. Data on technical success, diagnostic performance, complications, and radiation exposure were collected and analysed.

Results

A total of 70 and 65 patients underwent LDCT-guided and SDCT-guided CNB procedure, respectively. The technical success rates were 100% in both groups. The diagnostic yield, sensitivity, specificity, and overall diagnostic accuracy in the LDCT and SDCT groups were 71.4% and 67.7% (p = 0.637), 97.8% and 93.2% (p = 0.625), 100%, and 100%, and 98.6% and 95.4% (p = 0.560), respectively. The independent risk factor of diagnostic failure was less sample tissues (p = 0.012; 95% confidence interval: 0.033–0.651). Pneumothorax was found in 9 and 12 patients in the LDCT and SDCT groups, respectively (p = 0.369). Lung haemorrhage was found in 11 and 12 patients in the LDCT and SDCT groups, respectively (p = 0.671). The mean dose-length product was 38.3 ±17.0 mGy · cm and 376.0 ±118.7 mGy · cm in the LDCT and SDCT groups, respectively (p < 0.001).

Conclusions

Compared to SDCT, LDCT-guided CNB can provide comparable safety and diagnostic performance for LNs while reducing exposure to radiation.

Cutting Staff Radiation Exposure and Improving Freedom of Motion during CT Interventions: Comparison of a Novel Workflow Utilizing a Radiation Protection Cabin versus Two Conventional Workflows

This study aimed to evaluate the radiation exposure to the radiologist and the procedure time of prospectively matched CT interventions implementing three different workflows—the radiologist—(I) leaving the CT room during scanning; (II) wearing a lead apron and staying in the CT room; (III) staying in the CT room in a prototype radiation protection cabin without lead apron while utilizing a wireless remote control and a tablet. We prospectively evaluated the radiologist’s radiation exposure utilizing an electronic personal dosimeter, the intervention time, and success in CT interventions matched to the three different workflows. We compared the interventional success, the patient’s dose of the interventional scans in each workflow (total mAs and total DLP), the radiologist’s personal dose (in µSV), and interventional time. To perform workflow III, a prototype of a radiation protection cabin, with 3 mm lead equivalent walls and a foot switch to operate the doors, was built in the CT examination room. Radiation exposure during the maximum tube output at 120 kV was measured by the local admission officials inside the cabin at the same level as in the technician’s control room (below 0.5 μSv/h and 1 mSv/y). Further, to utilize the full potential of this novel workflow, a sterile packed remote control (to move the CT table and to trigger the radiation) and a sterile packed tablet anchored on the CT table (to plan and navigate during the CT intervention) were operated by the radiologist. There were 18 interventions performed in workflow I, 16 in workflow II, and 27 in workflow III. There were no significant differences in the intervention time (workflow I: 23 min ± 12, workflow II: 20 min ± 8, and workflow III: 21 min ± 10, p = 0.71) and the patient’s dose (total DLP, p = 0.14). However, the personal dosimeter registered 0.17 ± 0.22 µSv for workflow II, while I and III both documented 0 µSv, displaying significant difference (p < 0.001). All workflows were performed completely and successfully in all cases. The new workflow has the potential to reduce interventional CT radiologists’ radiation dose to zero while relieving them from working in a lead apron all day.

Radiation dose and image quality of CT fluoroscopy with partial exposure mode

PURPOSE

The present study aimed to evaluate the scan technique of computed tomography (CT)-guided puncture procedures using partial exposure mode (PEM) on the radiation dose of the operator's hand and image quality.

METHODS

Radiation dose was evaluated using three types of scanning methods: one-shot scan (OS), OS with a bismuth shield added (OSBismuth), and a half-scan (i.e., PEM) capable of an adjustable exposure angle. Dose evaluation was performed using a torso phantom, while a circular phantom simulating the liver parenchyma and lesions was used for image quality evaluation. For each scanning method, four measurements were made to determine the radiation dose to the operator's hand and the dose distribution on the surface of the patient's torso; the output-dose profile was determined from five measurements. Image quality was evaluated in terms of contrast and contrast-to-noise ratio (CNR). Analysis of variance (ANOVA) or Friedman test were used for comparison between groups as appropriate. The post hoc tests were Tukey's honestly difference (HSD) test for parametric data or Wilcoxon signed rank test with Bonferroni correction for nonparametric data.

RESULTS

The PEM yielded a radiation dose to the operator's hand that was 84% (0.35 vs. 2.33 mGy) lower than that of the OS. The dose to the patient's torso was reduced by 35% and 68% for the OSBismuth and PEM, respectively, relative to that of the OS. Compared with the CNR of the other two scanning methods (OS, 2.9±0.1; OSBismuth, 2.9±0.1), the PEM increased the standard deviation and decreased the CNR (2.1±0.04, Tukey's HSD, P < 0.001 for all). Images acquired with PEM showed visibility equivalent to that of other scanning methods when window conditions were adjusted.

CONCLUSION

This study demonstrated that CT-guided puncture procedure using PEM effectively reduces the operator's exposure to radiation while minimizing image quality deterioration.

Occupational Radiation Dose to Eye Lenses in CT-Guided Interventions Using MDCT-Fluoroscopy

In computed tomography (CT)-guided interventions (CTIs), physicians are close to a source of scattered radiation. The physician and staff are at high risk of radiation-induced injury (cataracts). Thus, dose-reducing measures for physicians are important. However, few previous reports have examined radiation doses to physicians in CTIs. This study evaluated the radiation dose to the physician and medical staff using multi detector (MD)CT-fluoroscopy, and attempted to understand radiation-protection and -reduction methods. The procedures were performed using an interventional radiology (IVR)-CT system. We measured the occupational radiation dose (physician and nurse) using a personal dosimeter in real-time, gathered CT-related parameters (fluoroscopy time, mAs, CT dose index (CTDI), and dose length product (DLP)), and performed consecutive 232 procedures in CT-guided biopsy. Physician doses (eye lens, neck, and hand; μSv, average ± SD) in our CTIs were 39.1 ± 36.3, 23.1 ± 23.7, and 28.6 ± 31.0, respectively. Nurse doses (neck and chest) were lower (2.3 ± 5.0 and 2.4 ± 4.4, respectively) than the physician doses. There were significant correlations between the physician doses (eye and neck) and related factors, such as CT-fluoroscopy mAs (eye dose: r = 0.90 and neck dose: r = 0.83). We need to understand the importance of reducing/optimizing the dose to the physician and medical staff in CTIs. Our study suggests that physician and staff doses were not significant when the procedures were performed with the appropriate radiation protection and low-dose techniques.

First experience of efficacy and radiation exposure in 320-detector row CT fluoroscopy-guided interventions

OBJECTIVE

We investigated the efficacy and exposure to radiation in 320-detector row computed tomography fluoroscopy-guided (CTF-guided) interventions.

METHODS

We analysed 231 320-detector row CTF-guided interventions (207 patients over 2 years and 6 months) in terms of technical success rates, clinical success rates, complications, scanner settings, overall radiation doses (dose-length product, mGy*cm), patient doses of peri-interventional CT series, and interventional CT (including CTF), as a retrospective cohort study. The relationships between patient radiation dose and interventional factors were assessed using multivariate analysis.

RESULTS

Overall technical success rate was 98.7% (228/231). The technical success rates of biopsies, drainages, and aspirations were 98.7% (154/156), 98.5% (66/67), and 100% (8/8), respectively. The clinical success rate of biopsies was 93.5% (146/156). All three major complications occurred in chest biopsies. The median total radiation dose was 522.4 (393.4-819.8) mGy*cm. Of the total radiation dose, 87% was applied during the pre- and post-interventional CT series. Post-interventional CT accounted for 24.4% of the total radiation dose. Only 11.4% of the dose was applied by CTF-guided intervention. Multilinear regression demonstrated that male sex, body mass index, drainage, intervention time, and helical scan as post-interventional CT were significantly associated with higher dose.

CONCLUSION

The 320-detector row CTF interventions achieved a high success rate. Dose reduction in post-interventional CT provides patient dose reduction without decreasing the technical success rates.

ADVANCES IN KNOWLEDGE

This is the first study on the relationship between various interventional outcomes and patient exposure to radiation in 320-detector row CTF-guided interventions, suggesting a new perspective on dose reduction.

Ultra-low-dose CT-guided lung biopsy in clinic: radiation dose, accuracy, image quality, and complication rate

BACKGROUND

Computed tomography (CT)-guided percutaneous lung biopsy is usually performed by helical scanning. However, there are no studies on radiation dose, diagnostic accuracy, image quality, and complications based on axial scan mode.

PURPOSE

To determine radiation dose, accuracy, image quality, and complication rate following an ultra-low-dose (ULD) protocol for CT-guided lung biopsy in clinic.

MATERIAL AND METHODS

A total of 105 patients were enrolled to receive CT-guided lung biopsy. The use of an ULD protocol (axial scan) for CT-guided biopsy was initiated. Patients were randomly assigned to axial mode (Group A) and conventional helical mode (Group B) CT groups. 64-slice CT was performed for CT-guided pulmonary biopsy with an 18-G coaxial cutting biopsy needle. The radiation dose, accuracy, image quality, and complication rate were measured.

RESULTS

Ninety-seven patients were selected for the final phase of the study. There was no significant difference between the two groups for pulmonary nodule characteristics (P > 0.05). The mean effective dose in group A (0.077 ± 0.010 mSv) was significantly reduced relative to group B (0.653 ± 0.177 mSv, P < 0.001). There was no significant difference in accuracy, image quality, and complication rate (P > 0.050) between the two modes.

CONCLUSION

An ULD protocol for CT-guided lung nodule biopsy yields a reduction in the radiation dose without significant change in the accuracy, image quality, and complication rate relative to the conventional helical mode scan.

Computed tomography-guided cutting needle biopsy for lung nodules: A comparative study between low-dose and standard dose protocols

We aim to compare the diagnostic accuracy, safety, and radiation exposure between low-dose and standard-dose computed tomography (CT)-guided cutting needle biopsy (CNB) for lung nodules.From January 2016 to August 2017, all consecutive patients admitted with lung nodule underwent low-dose or standard-dose CT-guided CNB procedure in our center. Diagnostic accuracy and radiation dose were compared.A total of 67 and 69 patients who underwent low-dose and standard-dose CT-guided CNB procedure were included in this study. Each patient underwent CT-guided CNB for 1 nodule. The technical success rates were 100% in both groups. The sensitivity, specificity, and overall diagnostic accuracy were 97.7%, 100%, and 98.5% for low-dose group and 91.5%, 100%, and 94.2% for standard-dose group. There was no significant difference in diagnostic accuracy (P = .380) between 2 groups. Pneumothorax was found in 8 and 15 patients in the low-dose and standard-dose groups, respectively (11.9% vs 21.7%, P = .127). Hemoptysis was found in 10 and 10 patients in the low-dose and standard-dose groups, respectively (14.9% vs 14.5%, P = .943). The mean dose-length product was 38.2 ± 17.2 mGy-cm and 375.3 ± 115.7 mGy-cm in the low-dose and standard-dose groups (P < .001). The mean dose-length product was 38.2 ± 17.2 mGy-cm and 375.3 ± 115.7 mGy-cm in the low-dose and standard-dose groups, respectively (P < .001). The mean effective dose was 0.5 ± 0.2 mSv and 5.3 ± 1.6 mSv in the low-dose and standard-dose groups, respectively (P < .001).Low-dose CT-guided CNB of lung nodules significantly decreased radiation dose compared with standard-dose CT. The low-dose protocol could provide similar diagnostic accuracy and safety as standard-dose CT-guided CNB for lung nodules.

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.

Computed Tomography-Guided Biopsy for Small (≤20 mm) Lung Nodules: A Meta-Analysis

PURPOSE

This study was designed to evaluate the diagnostic accuracy of computed tomography (CT)-guided biopsy for small lung nodules (SLNs) (≤20 mm) and to assess related complication rates.

METHODS

We reviewed the Pubmed, Embase, and Cochrane Library databases to identify all relevant studies published as of April 2020. Random effects modeling were then used to evaluate pooled data pertaining to technical success rates, diagnostic accuracy, pneumothorax rates, and rates of hemoptysis. The meta-analysis was conducted using Stata v12.0.

RESULTS

In total, we identified 25 relevant studies for incorporation into this meta-analysis, incorporating 2922 total CT-guided lung biopsy. Pooled technical success rates, diagnostic accuracy, pneumothorax rates, and hemoptysis rates were 94% (95% confidential interval [CI], 0.91-0.98), 90% (95% CI, 0.88-0.93), 19% (95% CI:, 0.15-0.24), and 12% (95% CI, 0.08-0.15), respectively. We observed significant heterogeneity among these studies for all 4 of these parameters (I = 90.0%, 82.7%, 88.6%, and 88.4%, respectively). When we conducted a meta-regression analysis, we did not identify any variables that influenced diagnostic accuracy or technical success, pneumothorax, or hemoptysis rates. Publication bias risk analyses suggested that there was relatively little risk of publication bias pertaining to pneumothorax rates (P = 0.400) or hemoptysis rates (P = 0.377). In contrast, we detected a high risk of publication bias pertaining to reported technical success rates (P = 0.007) and diagnostic accuracy (P = 0.000).

CONCLUSIONS

A CT-guided biopsy can be safely and effectively used to diagnose SLNs.

Transthoracic Needle Biopsy: How to Maximize Diagnostic Accuracy and Minimize Complications

Although transthoracic needle biopsy (TTNB) was introduced for lung biopsy about 40 years ago, it is still mainstay of pathologic diagnosis in lung cancer, because it is relatively inexpensive and can obtain tissue regardless of the tumor-bronchus relationship. With several technological advances, proceduralists can perform TTNB more safely and accurately. Utilizing ultrasound-guided biopsy for peripheral lesions in contact with the pleura and rapid on-site evaluation during the procedure are expected to make up the weakness of TTNB. However, due to the inherent limitations of the percutaneous approach, the incidence of complications such as pneumothorax or bleeding is inevitably higher than that of other lung biopsy techniques. Thorough understating of each biopsy modality and additional technique are fundamental for maximizing diagnostic accuracy and minimizing the complications.

THE EFFICACY OF RADPAD AS A RADIATION PROTECTION TOOL IN CT FLUOROSCOPY GUIDED LUNG BIOPSIES

Computed tomography fluoroscopy is now the preferred technique for percutaneous lung biopsies. However, concern regarding operator and patient radiation dose remains, which warrants further exploration into dose optimisation tools. This phantom-study aims to assess the dose reduction capabilities of RADPAD, a single-use patient drape designed to decrease staff exposure to scattered radiation. Dosemeters at the waist and eye levels were used to determine the whole-body and lens exposure during simulated lung biopsy procedures while using RADPAD and other combinations of personal protective equipment. RADPAD resulted in a 36% and 38% dose reduction for whole-body and eye exposure, respectively. However, when used in combination with radioprotective eyewear and aprons, RADPAD did not reduce the radiation dose further. Consequently, the use of standard personal protective equipment is a more cost-effective option for staff dose reduction. RADPAD is useful in the reduction of radiation dose to unprotected regions.

2020 Clinical Practice Guideline for Percutaneous Transthoracic Needle Biopsy of Pulmonary Lesions: A Consensus Statement and Recommendations of the Korean Society of Thoracic Radiology

Percutaneous transthoracic needle biopsy (PTNB) is one of the essential diagnostic procedures for pulmonary lesions. Its role is increasing in the era of CT screening for lung cancer and precision medicine. The Korean Society of Thoracic Radiology developed the first evidence-based clinical guideline for PTNB in Korea by adapting pre-existing guidelines. The guideline provides 39 recommendations for the following four main domains of 12 key questions: the indications for PTNB, pre-procedural evaluation, procedural technique of PTNB and its accuracy, and management of post-biopsy complications. We hope that these recommendations can improve the diagnostic accuracy and safety of PTNB in clinical practice and promote standardization of the procedure nationwide.

Computed Tomography Fluoroscopy-Guided Versus Conventional Computed Tomography-Guided Lung Biopsy: A Systematic Review and Meta-analysis

PURPOSE

This study aimed to compare the feasibility, safety, diagnostic accuracy, and radiation dose between computed tomography (CT) fluoroscopy (CTF)-guided and conventional CT (CCT)-guided lung biopsy.

METHODS

Relevant articles up until February 2020 were identified within the PubMed, Embase, and Cochrane Library databases. Diagnostic accuracy rate, pneumothorax, and pneumothorax requiring chest tube served as primary end points, with technical success, hemoptysis, operative time, and radiation dose serving as secondary end points. Pooled odds ratios (ORs) were calculated for the dichotomous variables. Pooled estimates of the mean difference (MD) were measured for the continuous variables.

RESULTS

This meta-analysis included 9 studies. Seven studies were retrospective, and 2 studies were randomized controlled trials. A total of 6998 patients underwent either CTF-guided (n = 3858) or CCT-guided (n = 3154) lung biopsy. The diagnostic accuracy rate was significantly higher in the CTF group compared with the CCT group (OR, 0.32; P < 0.00001). No significant differences were detected between the CTF and CCT groups in terms of incidence rates of pneumothorax (OR, 0.95; P = 0.84), rates of pneumothorax requiring chest tube insertion (OR, 0.95; P = 0.84), technical success rates (OR, 0.41; P = 0.15), incidence rates of hemoptysis (OR, 1.19; P = 0.61), operative time (MD, -4.38; P = 0.24), and radiation dose (MD, 158.60; P = 0.42). A publication bias was found for the end points of pneumothorax requiring chest tube insertion and operative time.

CONCLUSIONS

Compared with CCT-guided lung biopsy, CTF-guided lung biopsy could yield a higher diagnostic accuracy with similar safety and radiation exposure.

Radiation Exposure of Interventional Radiologists during Computed Tomography Fluoroscopy-Guided Percutaneous Cryoablation

PURPOSE

The principal aim of this study was to evaluate radiation exposure of interventionalists during computed tomography (CT) fluoroscopy-guided percutaneous cryoablation (PCA) using radiophotoluminescent glass dosimeters (RPLDs). The radioprotective effects of safety glasses and lead apron were also evaluated.

MATERIALS AND METHODS

Radiation exposure of interventionalists during 46 CT fluoroscopy-guided PCA procedures was evaluated. Entrance surface dose (ESD) was measured using RPLDs on multiple sites: five sites, representing eye lens exposure; five sites, representing body exposure; and four sites, representing skin exposure. The ESD values on multiple sites were compared between different PCA procedures (renal, liver, and bone).

RESULTS

The mean ESD on the X-ray-side hand exhibited the highest value (358.8 μGy). Regarding evaluation sites representing exposure to the eye lens, the highest ESD inside the radiation protective glasses was detected on the X-ray-side cheek (167.1 μGy). Most ESD values among multiple sites (10/14) were linearly correlated with CT fluoroscopy time. Among them, the ESD values measured during renal and liver PCA were relatively higher than those measured during bone PCA, especially on the chest area outside the lead apron, and on the X-ray tube-side elbow and hand during renal and bone PCA. Radioprotective effects of safety glasses and lead apron ranged from 44.6 to 50.6% and from 30.2 to 79.6%, respectively, on each evaluation site.

CONCLUSION

The site with the highest radiation exposure on interventionalists during CT fluoroscopy-guided PCA was the X-ray tube-side hand. Radiation exposure of interventionalists was at acceptable levels and consistent with the recommended dose limits.

Nonspecific benign pathological results on computed tomography-guided lung biopsy: A predictive model of true negatives

Objective

The aim of this study is to develop a predictive model for identifying true negatives among nonspecific benign results on computed tomography-guided lung biopsy.

Materials and Methods

This was a single-center retrospective study. Between December 2013 and May 2016, a total of 126 patients with nonspecific benign biopsy results were used as the training group to create a predictive model of true-negative findings. Between June 2016 and June 2017, additional 56 patients were used as the validation group to test the constructed model.

Results

In the training group, a total of 126 lesions from 126 patients were biopsied. Biopsies from 106 patients were true negatives and 20 were false-negatives. Univariate and multivariate logistic regression analyses were identified a biopsy result of "chronic inflammation with fibroplasia" as a predictor of true-negative results (P = 0.013). Abnormal neuron-specific enolase (NSE) level (P = 0.012) and pneumothorax during the lung biopsy (P = 0.021) were identified as predictors of false-negative results. A predictive model was developed as follows: Risk score = -0.437 + 2.637 × NSE level + 1.687 × pneumothorax - 1.82 × biopsy result of "chronic inflammation with fibroplasia." The area under the receiver operator characteristic (ROC) curve was 0.78 (P < 0.001). To maximize sensitivity and specificity, we selected a cutoff risk score of -0.029. When the model was used on the validation group, the area under the ROC curve was 0.766 (P = 0.005).

Conclusions

Our predictive model showed good predictive ability for identifying true negatives among nonspecific benign lung biopsy results.

Adequacy of Cytologic Samples by Ultrasound-Guided Percutaneous Transthoracic Fine-Needle Aspiration Cytology of Peripheral Pulmonary Nodules for Morphologic Diagnosis and Molecular Evaluations: Comparison With Computed Tomography–Guided Percutaneous Transthoracic Fine-Needle Aspiration Cytology

Context.—

Fine-needle aspiration cytology (FNAC) of pulmonary nodules is usually guided by computed tomography (CT), whereas ultrasonography (US) is generally considered not applicable for such purposes.

Objective.—

To evaluate the clinical applicability and diagnostic utility of US-guided transthoracic FNAC of peripheral pulmonary nodules.

Design.—

Ultrasonography-guided transthoracic FNAC was obtained from 40 selected patients with peripheral, subpleural, and paravertebral pulmonary nodules. Air-dried and Diff-Quik–stained smears were used for rapid on-site evaluation; additional smears were alcohol fixed for Papanicolaou staining. Cell blocks were set up for immunocytochemical and molecular studies; in 2 cases, a flow cytometry evaluation was also performed. The series was compared to 40 CT-guided pulmonary FNAC samples from patients with pleural, peripheral, and paravertebral pulmonary nodules, to evaluate differences in terms of diagnostic rate, time of execution, safety, and cost.

Results.—

The US-guided FNAC samples had results that were adequate and representative in 95% of cases. No significant differences were observed between the 2 groups in terms of diagnostic rate, number of passes, and cellularity of both smears and cell blocks. The mean time needed for the execution of US-guided FNAC was 13.1 minutes, whereas the mean time for CT-guided FNAC was 23.6 minutes. Thus, US-guided FNAC was significantly more rapid than CT-guided pulmonary FNAC. Because pneumothorax occurred in 1 individual who underwent US-guided FNAC and in 9 who underwent CT-guided FNAC, we might conclude that US-guided FNAC is a significantly safer procedure. Finally, comparing the costs of both procedures, US-guided FNAC is less expensive.

Conclusions.—

Our experience showed an elevated clinical applicability and diagnostic utility of US-guided transthoracic FNAC for selected pulmonary nodules.

Body interventional procedures: which is the best method for CT guidance?

OBJECTIVES

To compare sequential fluoroscopy guidance with spiral guidance in terms of safety, effectiveness, speed and radiation in interventional whole body procedures.

METHODS

This study was a retrospective analysis of data from the prospective, randomised controlled, multicentre CTNAV2 study. The present analysis included 385 patients: 247 in the sequential group (SEQ) and 138 in the spiral group (SPI). Safety was assessed by the number of major complications. Effectiveness was measured according to the number of targets reached. Data on procedural time and radiation delivered to patients were also collected.

RESULTS

There was no significant difference between the two groups (SEQ vs SPI) regarding the success rate (99.6% vs 99.3%, p = 0.680), procedural time (7 min 40 s ± 5 min 48 s vs 7 min 13 s ± 7 min 33 s, p = 0.507), or major complications (2.43% vs 5.8%, p = 0.101). Radiation dose to patients was 84% lower in the sequential group (54.8 ± 51.8 mGy cm vs 352.6 ± 404 mGy cm, p < 0.0001).

CONCLUSIONS

Sequential CT fluoroscopy-guided whole-body interventional procedures seems to be as safe, effective and fast as spiral guidance, while also yielding a significant decrease in the radiation dose to patients.

KEY POINTS

• Sequential CT fluoroscopy and spiral acquisition are comparable in terms of safety, effectiveness and speed. • Procedural times are comparable despite an increased number of acquisitions in sequential fluoroscopy. • Radiation dose to patients is 84% lower in sequential fluoroscopy compared with spiral CT.

Computed tomography-guided lung biopsy: a randomized controlled trial of low-dose versus standard-dose protocol

OBJECTIVES

To assess the relative diagnostic utility of low- and standard-dose computed tomography (CT)-guided lung biopsy.

METHODS

In this single-center, single-blind, prospective, randomized controlled trial, patients were enrolled between November 2016 and June 2017. Enrolled study participants were randomly selected to undergo either low- or standard-dose CT-guided lung biopsy. Diagnostic accuracy was the primary study endpoint, whereas technical success, radiation dose, and associated complications were secondary study endpoints.

RESULTS

In total, 280 patients underwent study enrollment and randomization, with 271 (low-dose group, 135; standard-dose group, 136) receiving the assigned interventions. Both groups had a 100% technical success rate for CT-guided lung biopsy, and complication rates were similar between groups (p > 0.05). The mean dose-length product (36.0 ± 14.1 mGy cm vs. 361.8 ± 108.0 mGy cm, p < 0.001) and effective dose (0.5 ± 0.2 mSv vs. 5.1 ± 1.5 mSv, p < 0.001) were significantly reduced in the low-dose group participants. Sensitivity, specificity, and overall diagnostic accuracy rates in the low-dose group were 91.8%, 100%, and 94.6%, respectively, whereas in the standard-dose group, the corresponding values were 89.6%, 100%, and 92.4%, respectively. These results indicated that diagnostic performance did not differ significantly between the 2 groups. Using univariate and multivariate analyses, we found larger lesion size (p = 0.038) and procedure-related pneumothorax (p = 0.033) to both be independent predictors of diagnostic failure.

CONCLUSIONS

Our results demonstrate that low-dose CT-guided lung biopsy can yield comparable diagnostic accuracy to standard-dose CT guidance, while significantly reducing the radiation dose delivered to patients.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02971176 KEY POINTS: • Low-dose CT-guided lung biopsy is a safe and simple method for diagnosis of lung lesions. • Low-dose CT-guided lung biopsy can yield comparable diagnostic accuracy to standard-dose CT guidance. • Low-dose CT-guided lung biopsy can achieve a 90% reduction in radiation exposure when compared with standard-dose CT guidance.

Analysis of Complications of Percutaneous Transthoracic Needle Biopsy Using CT-Guidance Modalities In a Multicenter Cohort of 10568 Biopsies

Objective

To analyze the complications of percutaneous transthoracic needle biopsy using CT-based imaging modalities for needle guidance in comparison with fluoroscopy in a large retrospective cohort.

Materials and Methods

This study was approved by multiple Institutional Review Boards and the requirement for informed consent was waived. We retrospectively included 10568 biopsies from eight referral hospitals from 2010 through 2014. In univariate and multivariate logistic analyses, 3 CT-based guidance modalities (CT, CT fluoroscopy, and cone-beam CT) were compared with fluoroscopy in terms of the risk of pneumothorax, pneumothorax requiring chest tube insertion, and hemoptysis, with adjustment for other risk factors.

Results

Pneumothorax occurred in 2298 of the 10568 biopsies (21.7%). Tube insertion was required after 316 biopsies (3.0%), and hemoptysis occurred in 550 cases (5.2%). In the multivariate analysis, pneumothorax was more frequently detected with CT {odds ratio (OR), 2.752 (95% confidence interval [CI], 2.325–3.258), p < 0.001}, CT fluoroscopy (OR, 1.440 [95% CI, 1.176–1.762], p < 0.001), and cone-beam CT (OR, 2.906 [95% CI, 2.235–3.779], p < 0.001), but no significant relationship was found for pneumothorax requiring chest tube insertion (p = 0.497, p = 0.222, and p = 0.216, respectively). The incidence of hemoptysis was significantly lower under CT (OR, 0.348 [95% CI, 0.247–0.491], p < 0.001), CT fluoroscopy (OR, 0.594 [95% CI, 0.419–0.843], p = 0.004), and cone-beam CT (OR, 0.479 [95% CI, 0.317–0.724], p < 0.001) guidance.

Conclusion

Hemoptysis occurred less frequently with CT-based guidance modalities in comparison with fluoroscopy. Although pneumothorax requiring chest tube insertion showed a similar incidence, pneumothorax was more frequently detected using CT-based guidance modalities.

Computed tomography-guided biopsy of small lung nodules: diagnostic accuracy and analysis for true negatives

Objective

We evaluated the diagnostic accuracy of computed tomography (CT)-guided transthoracic core needle biopsy (TCNB) for small (≤20-mm) lung nodules and identified predictive factors for true negatives among benign biopsy results.

Methods

From March 2010 to June 2015, 222 patients with small lung nodules underwent CT-guided TCNB. We retrospectively analysed data regarding technical success, diagnostic accuracy, and predictors of true negatives.

Results

The technical success rate was 100%. The TCNB results of the 222 lung nodules included malignancy (n = 136), suspected malignancy (n = 8), specific benign lesion (n = 17), and nonspecific benign lesion (n = 61). The final diagnosis of 222 lung nodules included malignant (n = 160), benign (n = 60), and nondiagnostic lesions (n = 2). The sensitivity, specificity, and overall diagnostic accuracy of CT-guided TCNB for small lung nodules were 90.0%, 100%, and 92.7%, respectively. Pneumothorax and haemoptysis occurred in 23 and 41 patients, respectively. Based on the Cox regression analysis, the significant independent predictive factor for true negatives was a biopsy result of chronic inflammation with fibroplasia.

Conclusions

CT-guided TCNB offers high diagnostic accuracy for small lung nodules, and a biopsy result of chronic inflammation with fibroplasia can predict a true-negative result.

Dual steristrip technique: a novel use of steristrips to reduce operator radiation dose during CT-guided intervention

OBJECTIVE

We describe a novel and safe needle-holding method that we have termed the 'dual steristrip technique'. This technique can be used to stabilize the bone biopsy needle without the need for the radiologist's hand to be in close proximity to the X-ray beam during CT-guided intervention.

MATERIALS AND METHODS

The dual steristrip technique uses steristrips to stabilize the bone biopsy needle and allows for accurate assessment of needle position and trajectory. This involves affixing one end of a steristrip to the skin 2 cm from the needle skin entry point, wrapping the mid-section of the steristrip around the biopsy needle and affixing the other end of the steristrip to the skin at the opposite side of the needle 2 cm from the needle skin entry point. A second steristrip is then applied in a similar fashion at 90° to the first steristrip.

RESULTS

In our institution, we have used the dual steristrip technique to stabilize the biopsy needle in certain cases where assessment of needle position/trajectory can be more challenging. This includes cases where there is a paucity of soft tissues overlying the bone or if the bone lesion is located in the superficial cortex. We have found it to be successful in 80% of cases.

CONCLUSIONS

The dual steristrip technique is a safe and effective needle stabilization method that should be considered by the interventional radiologist in challenging CT-guided bone biopsy cases.

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.

Robotic needle insertion during computed tomography fluoroscopy-guided biopsy: prospective first-in-human feasibility trial

INTRODUCTION

This was a prospective, first-in-human trial to evaluate the feasibility and safety of insertion of biopsy introducer needles with our robot during CT fluoroscopy-guided biopsy in humans.

MATERIALS AND METHODS

Eligible patients were adults with a lesion ≥ 10 mm in an extremity or the trunk requiring pathological diagnosis with CT fluoroscopy-guided biopsy. Patients in whom at-risk structures were located within 10 mm of the scheduled needle tract were excluded. Ten patients (4 females and 6 males; mean [range] age, 72 [52-87] years) with lesions (mean [range] maximum diameter, 28 [14-52] mm) in the kidney (n = 4), lung (n = 3), mediastinum (n = 1), adrenal gland (n = 1), and muscle (n = 1) were enrolled. The biopsy procedure involved robotic insertion of a biopsy introducer needle followed by manual acquisition of specimens using a biopsy needle. The patients were followed up for 14 days. Feasibility was defined as the distance of ≤ 10 mm between needle tip after insertion and the nearest lesion edge on the CT fluoroscopic images. The safety of robotic insertion was evaluated on the basis of machine-related troubles and adverse events according to the Clavien-Dindo classification.

RESULTS

Robotic insertion of the introducer needle was feasible in all patients, enabling pathological diagnosis. There was no machine-related trouble. A total of 11 adverse events occurred in 8 patients, including 10 grade I events and 1 grade IIIa event.

CONCLUSION

Insertion of biopsy introducer needles with our robot was feasible at several locations in the human body.

KEY POINTS

• Insertion of biopsy introducer needles with our robot during CT fluoroscopy-guided biopsy was feasible at several locations in the human body.

Initial Experience in CT-Guided Percutaneous Transthoracic Needle Biopsy of Lung Lesions Performed by a Pulmonologist

In the diagnosis of lung lesions, computed tomography (CT)-guided percutaneous transthoracic needle biopsy (PTNB) has a high diagnostic yield and a low complication rate. The procedure is usually performed by interventional radiologists, but the diagnostic yield and safety of CT-guided PTNB when performed by pulmonologists have not been evaluated. A retrospective study of 239 patients who underwent CT-guided PTNB at Yeungnam University Hospital between March 2017 and April 2018 was conducted. A pulmonologist performed the procedure using a co-axial technique with a 20-gauge needle. Then diagnostic yield and safety were assessed. The overall sensitivity, specificity, positive predictive value, and negative predictive value for the diagnosis of malignancy were 96.1% (171/178), 100% (46/46), 100% (171/171), and 86.8% (46/53), respectively. The diagnostic accuracy was 96.9% (217/224) and the overall complication rate was 33.1% (82/248). Pneumothorax, hemoptysis, and hemothorax occurred in 27.0% (67/248), 5.2% (13/248), and 0.8% (2/248) of the patients, respectively. Univariate analyses revealed that pneumothorax requiring chest tube insertion was a significant risk factor (odds ratio, 25.0; p < 0.001) for diagnostic failure. CT-guided PTNB is a safe procedure with a high diagnostic accuracy, even when performed by an inexperienced pulmonologist. The results were similar to those achieved by interventional radiologists as reported in previously published studies.

Diagnostic Yield of Ultrasound-guided Trucut Biopsy in Diagnosis of Peripheral Lung Malignancies

Introduction While computed tomography (CT) guided lung biopsy has been standard in histological diagnosis of pulmonary lesions, its use is limited to the interventional radiologists only. Ultrasound (US) guided biopsy of pulmonary lesions, which can be performed in-clinic by the pulmonologists only, is becoming a more popular technique. It also has the edge of real-time techniques, multi-planar imaging, and no radiation exposure to the patients. Methods This is a retrospective review of all the patients presenting with pleural-based lung lesions who underwent US-guided biopsy for diagnosis in the Department of Pulmonology, Liaquat University of Medical and Health Sciences Hospital, Hyderabad, Pakistan from 1^st January 2013 till 31^st December 2017. The diagnostic yield, sensitivity, specificity, and accuracy of US-guided biopsies were evaluated for diagnoses of peripheral lung malignancies. Results Ultrasound-guided biopsies for lung lesions has a diagnostic yield of 88.3%, sensitivity of 95.80%, and specificity of 90% with an accuracy of 95.35%. Pneumothorax as an immediate complication was seen only in 1.5% cases. Conclusion US-guided biopsies are a much safer diagnostic alternative to CT-guided biopsy for lung lesions and have high diagnostic yield. It doesn't require special radiological interventionists, can be performed at patients' bedsides, and the equipment is not as expensive.

Virtual Guidance of Percutaneous Transthoracic Needle Biopsy with C-Arm Cone-Beam CT: Diagnostic Accuracy, Risk Factors and Effective Radiation Dose

PURPOSE

C-arm cone-beam computed tomography-guided transthoracic lung core needle biopsy (CBCT-CNB) is a safe and accurate procedure for the evaluation of patients with pulmonary nodules. The purpose of our study was to evaluate the diagnostic performance, complication rates and effective radiation dose of CBCT-CNB with virtual guidance.

MATERIALS AND METHODS

We retrospectively collected data regarding 375 CBCT-CNBs performed with virtual guidance (XperGuide-Philips Healthcare, Best, The Netherlands) from January 2010 to June 2015 on 355 patients (mean age, 68.1 years ± 11.8; age range, 31-88 years). Patients were divided into groups and compared based on the diagnostic failure and lesion size (15 mm cutoff). Diagnostic performance, complication rate and effective radiation dose were investigated. Variables influencing diagnostic performance and complications were assessed using Student's T test and Pearson's χ² test.

RESULTS

The sensitivity, specificity, positive and negative predictive value and accuracy for patients subjected to CNBs were 96.8%, 100%, 100%, 100% and 97.2%, respectively. Considering risk factors for pneumothorax, no significant differences were found regarding patient and lesion characteristics. Perilesional hemorrhage occurred more frequently in older patients (p = 0.046) and in smaller lesions (p = 0.001). Hemoptysis was significantly more frequent in patients with perilesional hemorrhage (p = 0.01). Mean effective radiation dose in CBCT-CNB was 7.12 ± 8.78 mSv.

CONCLUSIONS

CBCT-CNB combined with virtual guidance is a reliable and accurate technique that allows exact localization of pulmonary lesions, effective preprocedural planning and real-time fluoroscopy altogether.

A Real-Time Tracking and Visualization System for Robot-Assisted Template Location Method Applied to Lung Cancer Brachytherapy

Accurate location of the puncture-guiding template, including the position and orientation, is essential for surgeons to implant radioactive seeds into an internal tumor in lung cancer brachytherapy. The objective of this paper is to establish a real-time tracking and visualization system (RTVS) to monitor the robot-assisted location process distantly and confirm the ultimate location accuracy without redundant computed tomography (CT) scans. RTVS consists of tracking and visualization components. A quaternion-based iterative closest point (QICP) algorithm for higher accuracy was proposed for the premised module of spatial registration. Arithmetic accuracy of QICP and clinical performance of RTVS were both validated by a series of experiments in a CT room. Spatial registration experiment shows that QICP consistently presents a distinctly higher degree of accuracy of 0.87±0.11 mm compared with other two conventional algorithms. RTVS, evaluated by tracking and visualization experiments, achieves a tracking accuracy of 1.05±0.05 mm position and (0.29±0.14) deg orientation. In addition, the time cost for template location is greatly reduced, so are the CT scan times. RTVS has the potential on lessening the workload of surgeons, reducing the CT radiation injury to the patient, and accelerating the progress of a brachytherapy surgery. The system presented means a new contribution to the lung cancer brachytherapy.

Influencing factors of pneumothorax and parenchymal haemorrhage after CT-guided transthoracic needle biopsy: single-institution experience

Purpose

To evaluate the incidences and influencing factors of pneumothorax and parenchymal haemorrhage after computed tomography (CT)-guided transthoracic needle biopsy (TTNB).

Material and methods

A retrospective analysis of 216 patients who underwent CT-guided TTNB was performed. The frequencies and risk factors of pneumothorax and parenchymal haemorrhage were determined. P values less than 0.05 were considered statistically significant.

Results

The incidences of pneumothorax and parenchymal haemorrhage were 23.1% and 45.4%, respectively. Twenty-two per cent of patients with pneumothorax needed percutaneous drainage, but all patients with parenchymal haemorrhage had clinical improvement after conservative treatment. No procedure-related mortality was detected. Univariate analysis showed that underlying pulmonary infection, lesion size of less than 1 cm, and lesion depth of more than 2 cm were significant influencing factors of pneumothorax. A significant relationship between the underlying chronic obstructive pulmonary disease (COPD) and the need for drainage catheter insertion was found. Pulmonary haemorrhage was more likely to occur in patients with underlying malignancy, solid pulmonary nodule, lesion size of 3 cm or less, and lesion depth of more than 3 cm. Consolidation was the protective factor for pulmonary haemorrhage. Sensitivity, specificity, positive predictive values (PPV) and negative predictive values (NPV), and accuracy of CT-guided core needle biopsy (CNB) for the diagnosis of malignancy were 95.7%, 100%, 100%, 93.3%, and 97.3%, respectively. The rate of diagnostic failure was 10.2%.

Conclusions

Pulmonary hemorrhage is the most common complication after CT-guided TTNB. Influencing factors for pneumothorax are underlying pulmonary infection, lesion size < 1 cm, and lesion depth > 2 cm. Underlying malignancy, solid pulmonary nodule, lesion size ≤ 3 cm, and lesion depth > 3 cm are associated with pulmonary haemorrhage.