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Preliminary clinical experience with a dedicated interventional robotic system for CT-guided biopsies of lung lesions: a comparison with the conventional manual technique

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Preliminary clinical experience with a dedicated interventional robotic system for CT-guided biopsies of lung lesions: a comparison with the conventional manual technique

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Evaluate the performance of a robotic system for CT-guided lung biopsy in comparison to the conventional manual technique. One hundred patients referred for CT-guided lung biopsy were randomly assigned to group A (robot-assisted procedure) or group B (conventional procedure). Size, distance from entry point and position in lung of target lesions were evaluated to assess homogeneity differences between the two groups. Procedure duration, dose length product (DLP), precision of needle positioning, diagnostic performance of the biopsy and rate of complications were evaluated to assess the clinical performance of the robotic system as compared to the conventional technique. All biopsies were successfully performed. The size (p = 0.41), distance from entry point (p = 0.86) and position in lung (p = 0.32) of target lesions were similar in both groups (p = 0.05). Procedure duration and radiation dose were significantly reduced in group A as compared to group B (p = 0.001). Precision of needle positioning, diagnostic performance of the biopsy and rate of complications were similar in both groups (p = 0.05). Robot-assisted CT-guided lung biopsy can be performed safely and with high diagnostic accuracy, reducing procedure duration and radiation dose in comparison to the conventional manual technique. • CT-guided biopsy is the main procedure to obtain diagnosis in lung tumours. • The robotic device facilitates percutaneous needle placement under CT guidance. • Robot-assisted CT-guided lung biopsy reduces procedure duration and radiation dose.
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1 23
European Radiology
ISSN 0938-7994
Eur Radiol
DOI 10.1007/s00330-014-3508-z
Preliminary clinical experience with a
dedicated interventional robotic system
for CT-guided biopsies of lung lesions: a
comparison with the conventional manual
technique
Michele Anzidei, Renato Argirò, Andrea
Porfiri, Fabrizio Boni, Marco Anile,
Fulvio Zaccagna, Domenico Vitolo, Luca
Saba, et al.
1 23
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INTERVENTIONAL
Preliminary clinical experience with a dedicated
interventional robotic system for CT-guided biopsies of lung
lesions: a comparison with the conventional manual technique
Michele Anzidei &Renato Argirò &Andrea Porfiri &Fabrizio Boni &Marco Anile &
Fulvio Zaccagna &Domenico Vitolo &Luca Saba &Alessandro Napoli &Andrea Leonardi &
Flavia Longo &Federico Venuta &Mario Bezzi &Carlo Catalano
Received: 22 May 2014 /Revised: 24 September 2014 /Accepted: 14 November 2014
#European Society of Radiology 2014
Abstract
Objective Evaluate the performance of a robotic system for
CT-guided lung biopsy in comparison to the conventional
manual technique.
Materials and methods One hundred patients referred for CT-
guided lung biopsy were randomly assigned to group A
(robot-assisted procedure) or group B (conventional proce-
dure). Size, distance from entry point and position in lung of
target lesions were evaluated to assess homogeneity differ-
ences between the two groups. Procedure duration, dose
length product (DLP), precision of needle positioning, diag-
nostic performance of the biopsy and rate of complications
were evaluated to assess the clinical performance of the ro-
botic system as compared to the conventional technique.
Results All biopsies were successfully performed. The size
(p=0.41), distance from entry point (p= 0.86) and position in
lung (p=0.32) of target lesions were similar in both groups
(p=0.05). Procedure duration and radiation dose were signif-
icantly reduced in group A as compared to group B (p=
0.001). Precision of needle positioning, diagnostic perfor-
mance of the biopsy and rate of complications were similar
in both groups (p=0.05).
Conclusion Robot-assisted CT-guided lung biopsy can be
performed safely and with high diagnostic accuracy, reducing
procedure duration and radiation dose in comparison to the
conventional manual technique.
Key Points
CT-guided biopsy is the main procedure to obtain diagnosis
in lung tumours.
The robotic device facilitates percutaneous needle place-
ment under CT guidance.
Robot-assisted CT-guided lung biopsy reduces procedure
duration and radiation dose.
Keywords Robot .Lung biopsy .Lung cancer .
CT-guidance .Interventional radiology
Introduction
CT-guided lung biopsy is the procedure of choice to obtain
diagnoses in patients with pulmonary lesions suggestive of
malignancy at imaging [13]. Following the recent advances
in targeted therapies, biopsy of unresectable lung lesions has
also become necessary in order to assess genetic mutations in
unresectable non-small cell cancers (NSCLC), with core bi-
opsy usually being preferred to aspiration cytology owing to
the larger specimens made available for molecular analysis
[4]. CT-guided lung biopsy can be performed either with the
step-and-shoot or the fluoroscopic technique: the step-and-
M. Anzidei (*):R. Argirò :A. Porfiri :F. Boni :F. Zaccagna :
A. Napoli :A. Leonardi :M. Bezzi :C. Catalano
Department of Radiological, Oncological and Anatomopathological
Sciences - Radiology Sapienza, University of Rome, Viale Regina
Elena 324, 00161 Rome, Italy
e-mail: michele.anzidei@gmail.com
M. Anile :F. Venu t a
Department of Thoracic Surgery Sapienza, University of Rome,
Rome, Italy
D. Vitolo
Department of Radiological, Oncological and Anatomopathological
Sciences - Pathology Sapienza, University of Rome, Rome, Italy
L. Saba
Department of Radiology, Azienda Ospedaliero Universitaria
(A.O.U.), di Cagliari-Polo di Monserrato, Monserrato, Italy
F. Lo n g o
Department of Radiological, Oncological and Anatomopathological
Sciences - Oncology Sapienza, University of Rome, Rome, Italy
Eur Radiol
DOI 10.1007/s00330-014-3508-z
Author's personal copy
shoot approach is preferred in larger, non-moving lesions,
while CT-fluoroscopy is more advantageous when targeting
smaller lesions or nodules in the lower lobes that are suscep-
tible to respiratory motion [5]. Both procedures have technical
limitations that should be taken into consideration; in partic-
ular the step-and-shoot technique is based on the operators
subjective assessment of needle path and positioning and may
result in increased procedure duration and complication rate,
whereas CT-fluoroscopy is significantly faster and more pre-
cise but significantly raises radiation dose to both operator and
patient [6,7]. Various assisting technologies have been pro-
posed in order to increase the diagnostic accuracy and reduce
the duration of CT-guided biopsies, including external laser
targeting [8] and augmented reality (i.e. with a live indirect
view of anatomy by computer-generated video input) [9].
Dedicated interventional robotic systems that operate under
imaging guidance also became available recently [10].
However, while these systems may theoretically represent an
important step toward the automation of interventional proce-
dures, clinical experience and comparative data with conven-
tional techniques are still lacking or insufficient. The
ROBIOEX (Perfint Healthcare Pvt. Ltd, Florence, OR,
USA) is a CE approved robotic positioning system that facil-
itates percutaneous needle placement during CT-guided inter-
ventional procedures and that has been successfully tested for
CT-guided biopsy and ablation on phantoms [11] and for
clinical radiofrequency ablation of liver lesions [12]. The
objective of this study was to evaluate the clinical perfor-
mance of this system for CT-guided biopsy of lung lesions
in comparison with the conventional manual technique.
Materials and methods
Patient population and study details
This was a single-centre, double-arm, non-sponsored, pro-
spective study and received the approval of local institution
review board. Between June 2013 and February 2014, 115
patients with previously diagnosed lung lesions suggestive of
malignancy at chest CT, PET-CT or both were referred to the
thoracic surgery department of our tertiary care hospital for
histological characterization. Fifteen patients were excluded
from the study population (three patients refused further diag-
nosis/treatment, in five patients the lesions were characterized
as lung metastases following review of available imaging and
in seven patients diagnosis was obtained with bronchoscopy
and transbronchial biopsy). The remaining 100 patients (63
male, 37 female, age range 4888 years, mean age 65 ±4 years)
were referred for CT-guided lung biopsy and randomly
assigned to group A (robot-assisted procedure) or group B
(conventional procedure). All enrolled patients gave their
written informed consent to participation after being
thoroughly informed of the benefits and potential risks of the
procedure.
Pre-procedure
All procedures were performed by the same radiologist (MA,
8 years of experience in CT-guided interventions, including
more than 300 lung biopsies) on a 128-MDCT dual-source
scanner (Somatom Definition, Siemens, Erlangen, Germany).
A standard inspiratory breath-hold scan of the chest (100 kV,
100 mAs, detector configuration 128×1 mm, slice thickness
1 mm, reconstruction interval 1 mm) was acquired in all cases
prior to biopsy, in order to confirm the presence and to assess
the position of the target lesion. Patients were laid on a
vacuum stabilization mattress and positioned in order to re-
duce at minimum the intrapleural path of the needle, as well as
to avoid critical lung structures (vessels, bronchi and fissures).
Local anaesthesia was performed with 10 mL of 1 % lidocaine
along the projected path of the biopsy needle into the soft
tissues, down to the epipleural space. In all cases an 18-G,
150/200-mm-long modified Menghini end-cutting needle
(SURECUT, TSK Laboratory, Tochigi-Shi, Japan) was used
for tissue sampling. Targeting CT scans were acquired with a
low-dose interventional protocol (100 kV, 50 mAs, detector
configuration 128×1 mm, slice thickness 1 mm, reconstruc-
tion interval 1 mm).
Conventional biopsy technique
All conventional biopsies were performed with the step-and-
shoot technique to assess needle positioning and angulation.
The z-axis extension of targeting scans was limited to include
only the needleand the target lesion. A minimum of two scans
(before the pleura and into the lesion) was required to target
lesions adjacent to the chest wall and a minimum of three
scans (before the pleura, midway to the lesion, into the lesion)
was required for deeper lesions. Additional scans and
multiplanar reconstructions were performed in real time when
necessary for needle adjustment. Once the needle tip was in
position, biopsy was performed with a combination of aspira-
tion and push/rotation movements.
Robot-assisted biopsy technique
Positioning and docking of the robotic system were performed
as previously described [11], with the arm and planning con-
sole located to the side of the CT bed (left or right, depending
on the required access) and firmly coupled to ground metal
plates on the floor to ensure stability. A preliminary inspira-
tory breath-hold CT of the chest was performed using a Breath
Hold® respiratory belt coupled to a light sign (Medspira,
Minneapolis, USA) mounted on a flexible arm, in order to
monitor the extent of chest movement and instruct patients to
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maintain and reproduce proper apnoea (Fig. 1). Images were
then exported over a local area network to the ROBIOEX
workstation for biopsy planning. The centre of the target
lesion and the entry point on the skin were determined by
the operator, while the angulations of the needle, the depth of
the target and the needle path were automatically calculated by
the workstation and displayed in real time (Fig. 2). Each
parameter was readily modifiable by the operator in order to
avoid critical structures, such as ribs, bronchi and vessels.
Once the plan was confirmed, the CT table was moved to
the coordinates displayed on the workstation and the robotic
arm was activated and positioned for biopsy execution. A
plastic holder with a disposable bush was placed at the end
effector of the robotic arm to guide needle insertion.
Subsequently, the needle was manually inserted through the
chest wall directly into the lesion in a single pass, while the
patient maintained breath-hold to the same extent as that of the
initial positioning CT scan, guided by the light sign coupled to
the respiratory belt. After decoupling the needle from the end
effector and retraction of the robotic arm, needle positioning
was confirmed with a further CT scan (Figs. 3and 4)and
adjustments were performed if required. Biopsy was then
performed similarly to the conventional approach.
Data analysis
The homogeneity assessment of the two groups included
evaluation of the size, distance from entry point and position
in lung of target lesions. The size and distance from entry
point were compared between the two groups with the un-
paired sample ttest. Differences in the location (according to
lobar anatomy) of target lesions between the two groups were
assessed with the MannWhitney Utest.
In order to demonstrate statistically significant differences
(p<0.01) of clinical and technical performance between the
conventional biopsy approach and the robot-assisted tech-
nique, the following parameters were evaluated in the two
groups:
Procedure duration (including planning time) and dose
length product (DLP) were compared with the unpaired
sample ttest.
Number of needle adjustments was compared with the
unpaired sample ttest.
Planar and craniocaudal deviations of the needle tip from
the planned target were calculated in millimetres and
compared between the two groups with the unpaired
sample ttest. Multiplanar reformatted images were used
for the evaluation of z-axis deviation.
Orbital and craniocaudal angular deviations at the target
from the projected needle path were calculated in degrees
(°) for robot-assisted biopsies only. Multiplanar
reformatted images were used for the evaluation of
craniocaudal angular deviation.
Diagnostic performance of the biopsy procedure was
evaluated qualitatively (diagnostic/non-diagnostic sam-
pling) and compared with the MannWhitney test.
The rate of complications in the two groups was evaluat-
ed following the clinical practice guidelines of the Society
of Interventional Radiology [13] (no complications/minor
complications/major complications) and compared with
the MannWhitney Utest.
Results
All biopsies were successfully performed under CT guidance
in both groups. Lesions size (p=0.41), distance from entry
point (p=0.86) and lesions location (p=0.32) were similar in
the two groups. Full results of the homogeneity assessment of
the two groups are given in Table 1.
In group A procedure duration was significantly shorter
(p=0.001), DLP was lower (p=0.001) and just occasional
needle adjustments were required as compared to group B
(p=0.000). Planar and craniocaudal deviations of the needle
Fig. 1 Patient preparation. Respiratory belt placed in patients sight (a,
arrow) and coupled to the light sign (b,arrow). The belt registers the
extent of chest movement at each respiratory act and displays this as
coloured dots. More dots light up with wider respiratory movements. The
patients were asked to control their breath during the procedure trying to
avoid lighting of the outer dots
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tip from the planned target were similar in both groups (p=
0.05), while the orbital (transversal on the x-axis) and
craniocaudal (longitudinal on the z-axis) angular deviations
from the projected needle path in robot-assisted biopsies were
1° and 2.5 ±0.5° (Fig. 5). The diagnostic performance of
CT-guided biopsies was similar in the two groups (p=0.05),
with four patients in group A and three patients in group B
Fig. 2 Biopsy planning on the ROBIOEX workstation. Target lesion
in the lower right lobe at contrast-enhanced CT (a,arrow), surrounded by
atelectasis (a,arrowhead). The entry point on the skin (b,arrow)and
centre of target lesion (c,arrow) are determined by the operator. The
angulations and insertion path of the needle are automatically calculated
by the workstation and displayed in real time
Fig. 3 Needle positioning. Needle in position before insertion (a,arrow).
Needle insertion through the chest wall directly into the lesion in a single
pass (b,arrow). Needle in final position (c,arrow) after detachment from
end effector and retraction of the robotic arm
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requiring re-biopsy due to inadequate quality of the biopsy
sample. The rate of complications was comparable in the two
groups (p=0.05); there were three (6 %) cases of pneumotho-
rax in group A and two (4 %) cases of pneumothorax in group
B requiring chest tube drainage and prolonged hospitalization.
Minor complications (including small pneumothorax not re-
quiring therapy and self-limiting peri-lesional haemorrhages)
occurred in two (4 %) cases in group A and four (7 %) in
group B. Full results of the assessment of the clinical and
technical performance of the two groups are given in Table 2.
Discussion
Imaging-guided interventional techniques currently represent
a fundamental tool in diagnosis and treatment of oncologic
pathologies. Among the various guidance modalities, CT is
the method of choice in the chest region owing to its excellent
spatial and contrast resolution for the visualization of lung
parenchyma, airways and cardiovascular structures that safely
allows biopsy of lung and mediastinal lesions, percutaneous
tube placement and thermal ablation of lung tumours. The
conventional technique for CT-guided interventional proce-
dures requires a trial-and-error method with the step-and-
shoot approach, or the application of a real-time fluoroscopic
monitoring in order to visualize and modify the path of
needles and percutaneous probes. Even if the clinical perfor-
mance of conventional approaches is highly reliable in expert
hands [47], these methods present well-known technical
limitations and their successful application depends signifi-
cantly on operatorsmanual skill and experience. In order to
reduce such operator dependence, several assisting devices
have been developed and tested in clinical practice, including
external laser [8]oroptical[14] targeting systems that project
and/or guide the needle path onto the skin surface, electro-
magnetic tracking with image fusion [15] and augmented
reality system under infrared guidance that display a real-
time simulation of needle movements [9]. Preliminary reports
are encouraging, but it should be noted that the success of
these technologies is highly dependent on the integration
between the assisting software/hardware, the CT system and
the operator, with increased complexity and costs as compared
to conventional techniques. Moreover, with the approaches
mentioned above the dependence on operator experience is
reduced but not completely eliminated, not mentioning the
need for adequate training. On the other hand, the use of
medical robots for surgical or imaging-guided procedures
allows extremely accurate tool guidance with stable access,
leading to increased precision, accuracy and reproducibility in
a variety of applications, including percutaneous ablations,
biopsies, orthopaedic fixture placement, hollow viscera or
solid organ access [10]. While earlier robots required exten-
sive installation and were often cumbersome to operate, being
time consuming and economically disadvantageous [16,17],
more recent systems, such as the ROBIOEX, require
minimal effort to be mounted and registered to the imaging
Fig. 4 Positioning confirmation after control scan, immediately before
biopsy. Adjacent slices demonstrate overlapping between the planned
needle path (green line) and the actual needle position at the end of
insertion. Robot-assisted biopsy allowed correct sampling of tumour
tissue avoiding atelectasis. Final histological diagnosis was
adenocarcinoma
Tabl e 1 Full results of the homogeneity assessment of the two groups
Parameter Group A Group B pvalue
Lesion size (mm) 40.7±23.9 (range 15150) 35.5±25 (range 13.5160) 0.41
Distance from Entry point (mm) 73.1±30.7 (range 20135) 72.1±21.6 (range 18117) 0.86
Lesion location (according to lobar anatomy) RUL (n 11) RUL (n 9) 0.32
LUL (n 6) LUL (n 8)
ML (n 3) ML (n 2)
RLL (18) RLL (16)
LLL (12) LLL (15)
Values are expressed as average± standard deviation
RUL right upper lobe, LUL left upper lobe, ML middle lobe, RLL right lower lobe, LLL left lower lobe
Eur Radiol
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device [11], reducing the complexity of the procedure. Also
the fully automated movement of the robotic arm represents a
relevant advantage that removes the need for manual or joy-
stick adjustments in the pretreatment phase that are necessary
with other devices [18,19] and may further complicate the
clinical workflow. From a clinical point of view, our study
demonstrated in a large patient population that the presented
robotic system facilitates CT-guided lung biopsies, with re-
sults that are substantially in line with previous reports on
biopsies in phantoms [11] and clinical radiofrequency ablation
of liver lesions [12]. It should be considered that, apart from
these two preliminary studies performed with the samerobotic
platform, there is no literature evidence of large clinical series
of robot-assisted CT-guided interventions, in particular for
what regards chest procedures; hence, an indirect comparison
with the performance of different robotic devices is currently
impossible. In our single-centre experience, the precision in
lesion targeting, the diagnostic performance of the biopsy
sampling and the rate of complications in the robot-assisted
procedures were comparable to those of conventional biop-
sies, with accurate needle positioning and very few adjustment
required even in lesions as small as 15 mm, but the use of the
robot significantly reduced procedure duration and radiation
dose in comparison to the unassisted technique. This observa-
tion is particularly relevant, since in our study all procedures
were performed by an operator with previous experience of
more than 300 conventional CT-guided lung biopsies and,
notwithstanding this expertise, significant reduction of proce-
dure duration and radiation dose were in any case obtained in
robot-assisted procedures as compared to the conventional
technique. In this regard, future work should aim to evaluate
when and how operators with different levels of experience
may benefit from robot assistance in daily clinical routine, and
assess potential differences in the clinical performance of
robot-assisted procedures between expert and non-expert
Fig. 5 Biopsy of a deep solitary lung nodule in the right upper lobe. The
maximum transverse diameter of the nodule was 10 mm and its
craniocaudal size was 15 mm. Planning CT demonstrates the desired
needle path and tip positioning (a,arrowhead). Control CT scan after
needle positioning shows a slight angular deviation of the needle tip
resulting in a 1.5-mm deviation from the planned path (b,arrowhead).
Notwithstanding the deviation, biopsy was successfully performed
without further needle adjustments, achieving final histological
diagnosis of adenocarcinoma
Tabl e 2 Full results of the assessment of the clinical and technical performance of the two groups
Parameter Group A Group B pvalue
Procedure duration (min) 20.1±11.3 (range 1031) 31.4±10.2 (range 1842) 0.001
DLP (mGy) 324± 114.5 (range 117386) 541.2±446.8 (range 334589) 0.001
Number of needle adjustments 2.7± 2.6 (range 14) 4 (range 212) 0.000
Deviations on the xand yaxes (mm) 2.3± 1.1 (x)2.5±1.5(y) (range 18) 3.0± 1.3 (x)2.1±1.6(y)(range211) 0.05
Orbital (o) and craniocaudal (c)
deviations (°)
1° (o) 1.5±0.5° (c) N/A N/A
Final diagnosis 18 ADCA, 9 SCC, 6 SCLC, 10 mets,
3benignant
15 ADCA, 10 SCC, 7 SCLC, 14 mets,
1benignant
0.05
4 rebiopsy (1 ADCA, 2 SCC, 1 SCLC) 3 rebiopsy (2 ADCA, 1 SCC)
Complications (%) 10.4 11 0.05
Values are expressed as average± standard deviation
ADCA adenocarcinoma, SCC squamous cell carcinoma, SCLC small cell carcinoma, mets metastases, N/A not acquired
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radiologists. Moreover, even if a dedicated cost-analysis is
currently unavailable, it could be speculated that the use of
interventional robotic systems will be probably even more
beneficial in clinical settings in which financial resources or
time for appropriate training of interventional radiologists is
lacking, pushing less expert, non-interventional operators to
perform simple imaging-guided procedures. Even if these
preliminary results are encouraging, this study has some lim-
itations. First, the sample size was not determined in advance
with a power analysis in order to increase the relevance of the
statistical evaluation. Moreover, a statistical subanalysis based
on the anatomic characteristics of the target lesions (size,
distance to pleura and position in lung) was not performed;
hence we cannot provide clustered data on system perfor-
mance for the biopsy of smaller and hardly accessible lesions,
which should be the ideal target for robot-assisted procedures.
Last, an independent evaluation of the status of the lung
parenchyma surrounding the target lesions was not available
in order to assess the influence of local pulmonary factors
(emphysema, fibrosis, bronchiectases) on the rate of compli-
cations in the two groups, even if this parameter was probably
not influential, since our complication rates do not differ from
those reported in the literature [47]. Notwithstanding these
limitations, the results of our study demonstrate that robot-
assisted CT-guided lung biopsy is a safe and accurate inter-
ventional technique that can reduce procedure duration and
radiation dose in comparison to the conventional manual
approach even in expert hands. Further studies are needed to
confirm these data and to evaluate the performance of robot-
assisted interventional procedures in other clinical scenarios.
Acknowledgments The scientific guarantor of this publication is Dr.
Michele Anzidei. The authors of this manuscript declare no relationships
with any companies whose products or services may be related to the
subject matter of the article. The authors state that this work has not
received any funding. Dr. Fulvio Zaccagna kindly provided statistical
advice for this manuscript. Institutional review board approval was ob-
tained. Written informed consent was obtained from all subjects (patients)
in this study. No study subjects or cohorts have been previously reported.
Methodology: prospective, randomised controlled trial, performed at one
institution.
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... Needle biopsy is still the main method for obtaining histological characterization (12). In the past years, there has been a continuous development of novel technologies to improve diagnostic accuracy, reduce trauma and complications, for instance robot-assisted CT-guided lung biopsy has emerged as a safe technique in clinical practice (13), however, lung biopsies are still invasive and may result in pneumothorax, bleeding and/or other complications. 2-[ 18 F]-Fluoro-2-deoxy-D-glucose positron emission tomography ( 18 F-FDG PET) is a functional imaging technology that can reflect glucose metabolism in biological tissues (14, 15). ...
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Background Lung cancer has become one of the deadliest tumors in the world. Non-small cell lung cancer (NSCLC) is the most common type of lung cancer, accounting for approximately 80%-85% of all lung cancer cases. This study aimed to investigate the value of diffusion kurtosis imaging (DKI), diffusion-weighted imaging (DWI) and 2-[ ¹⁸ F]-fluoro-2-deoxy-D-glucose positron emission tomography ( ¹⁸ F-FDG PET) in differentiating squamous cell carcinoma (SCC) and adenocarcinoma (AC) and to evaluate the correlation of each parameter with stage and proliferative status Ki-67. Methods Seventy-seven patients with lung lesions were prospectively scanned by hybrid 3.0-T chest ¹⁸ F-FDG PET/MR. Mean kurtosis (MK), mean diffusivity (MD), apparent diffusion coefficient (ADC), maximum standard uptake value (SUVmax), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) were measured. The independent samples t test or Mann–Whitney U test was used to compare and analyze the differences in each parameter of SCC and AC. The diagnostic efficacy was evaluated by receiver operating characteristic (ROC) curve analysis and compared with the DeLong test. A logistic regression analysis was used for the evaluation of independent predictors. Bootstrapping (1000 samples) was performed to establish a control model, and calibration curves and ROC curves were used to validate its performance. Pearson’s correlation coefficient and Spearman’s correlation coefficient were calculated for correlation analysis. Results The MK and ADC values of the AC group were significantly higher than those of the SCC group (all P< 0.05), and the SUVmax, MTV, and TLG values of the SCC group were significantly higher than those of the AC group (all P<0.05). There was no significant difference in the MD value between the two groups. Moreover, MK, SUVmax, TLG and MTV were independent predictors of the NSCLC subtype, and the combination of these parameters had an optimal diagnostic efficacy (AUC, 0.876; sensitivity, 86.27%; specificity, 80.77%), which was significantly better than that of MK (AUC = 0.758, z = 2.554, P = 0.011), ADC (AUC = 0.679, z = 2.322, P = 0.020), SUVmax (AUC = 0.740, z = 2.584, P = 0.010), MTV (AUC = 0.715, z = 2.530, P = 0.011) or TLG (AUC = 0.716, z = 2.799, P = 0.005). The ROC curve showed that the validation model had high accuracy in identifying AC and SCC (AUC, 0.844; 95% CI, 0.785-0.885);. The SUVmax value was weakly positively correlated with the Ki-67 index (r = 0.340, P< 0.05), the ADC and MD values were weakly negatively correlated with the Ki-67 index (r = -0.256, -0.282, P< 0.05), and the MTV and TLG values were weakly positively correlated with NSCLC stage (r = 0.342, 0.337, P< 0.05). Conclusion DKI, DWI and ¹⁸ F-FDG PET are all effective methods for assessing the NSCLC subtype, and some parameters are correlated with stage and proliferation status.
... A stereotactic CT-guided robot (Perfint MAXIO) is commercially available 3 and offers enhanced capabilities in all of these functions. Initial studies have demonstrated more accurate needle placement, 4,5 shorter procedure times 6 and lower radiation dose 7 than conventional freehand techniques, although the device has not been evaluated in the UK. The overall aim of this work is to report our initial experience in robotic guidance for interventional oncology applications. ...
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Objectives A commercially available CT guided robot offers enhanced abilities in planning, targeting, and confirming accurate needle placement. In this short communication, we describe our first UK experience of robotic Interventional Oncology procedures. Methods We describe the device, discuss installation, operation, and report upon needle insertion success, accuracy (path deviation; PD and tip deviation; TD), number of adjustments, complications, and procedural success. Results Nine patients (seven males), median age 66 years (range 43–79) were consented for biopsy or ablation between March and April 2021. Needle placement in biopsy was more accurate than ablation (1 vs 11 mm PD and 1 vs 20 mm TD) and required fewer adjustments (median 0 vs 5). No complications arose, and all procedures were successful (diagnostic material obtained or complete ablation at follow up). Conclusions Short procedure times and very high levels of accuracy were readily achieved with biopsy procedures, although tumour ablation was less accurate which likely reflects higher procedural complexity. Advances in knowledge Achieving highly accurate robotic biopsy with is feasible within a very short time span. Further work is required to maximise the potential of robotic guidance in tumour ablation procedures, which is likely due to higher complexity giving a longer learning curve.
... Therefore, deploying the IRE probes precisely and ablating the tumor completely in a short operation time is imperative. 2,3 Traditional hand puncture requires abundant surgical experience. Manual inserting and adjusting the probes repeatedly increases the radiation dose to the patient, prolonging the anesthesia time, and increasing the chance of surgical complications. ...
Article
Background: To evaluate the feasibility and safety of a robot-guided IRE (irreversible electroporation) ablation system for the treatment of pancreatic head carcinoma. Methods: A total of 20 cases with pancreatic head carcinoma were divided into two groups: 11 cases in group A with manual probes placement and 9 cases in group B with robotic navigated probe placement. The two groups were compared in terms of planning time before puncture (PTBP), puncture time (PT), the total time of electrode deployment (TT), number of scans (NS), and punctual accuracy of the single electrode (PA). Results: Each probe was successfully punctured, and no complications were detected. P-values were calculated for all the parameters, using the SPSS 25.0 software and the t-test. Conclusions: The new robot can reduce the total operating time as compared to the manual probe placement with the same accuracy in the IRE of pancreatic head carcinoma. This article is protected by copyright. All rights reserved.
... Robot approaches to lung biopsy in prior work can be broadly categorized by their physical approach to lesions, the number of active joints, their mechanical stiffness, and their robot controllers. Both platforms that use industrial robot arms for transthoracic biopsy and thus have limited reach into the bore due to their arm size [13], [12], [14] and those with passive setup joints suffer from a limited active range of motion and have a reduced number of feasible biopsy approaches [15], [16], [17], [18] but may be well suited for smaller anatomies with single approach vectors. Robotic procedures using a device secured to the chest [19], [20], [21] observe additional limitions in reachability but may have better precision for positioning instruments to anatomy as the body shifts. ...
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This paper describes the design, manufacture, and performance of a highly dexterous, low-profile, 7 Degree-of-Freedom (DOF) robotic arm for CT-guided percutaneous needle biopsy. Direct CT guidance allows physicians to localize tumours quickly; however, needle insertion is still performed by hand. This system is mounted to a fully active gantry superior to the patient's head and teleoperated by a radiologist. Unlike other similar robots, this robot's fully serial-link approach uses a unique combination of belt and cable drives for high-transparency and minimal-backlash, allowing for an expansive working area and numerous approach angles to targets all while maintaining a small in-bore cross-section of less than $16cm^2$. Simulations verified the system's expansive collision free work-space and ability to hit targets across the entire chest, as required for lung cancer biopsy. Targeting error is on average $<1mm$ on a teleoperated accuracy task, illustrating the system's sufficient accuracy to perform biopsy procedures. The system is designed for lung biopsies due to the large working volume that is required for reaching peripheral lung lesions, though, with its large working volume and small in-bore cross-sectional area, the robotic system is effectively a general-purpose CT-compatible manipulation device for percutaneous procedures. Finally, with the considerable development time undertaken in designing a precise and flexible-use system and with the desire to reduce the burden of other researchers in developing algorithms for image-guided surgery, this system provides open-access, and to the best of our knowledge, is the first open-hardware image-guided biopsy robot of its kind.
Chapter
Deformable lung CT registration plays an important role in image-guided navigation systems, especially in the situation with organ motion. Recent progress has been made in image registration by utilizing neural networks for end-to-end inference of a deformation field. However, there are still difficulties to learn the irregular and large deformation caused by organ motion. In this paper, we propose a patient-specific lung CT image registration method. We first decompose the large deformation between the source image and the target image into several continuous intermediate fields. Then we compose these fields to form a spatio-temporal motion field and refine it through an attention layer by aggregating information along motion trajectories. The proposed method can utilize the temporal information in a respiratory circle and can generate intermediate images which are helpful in image-guided systems for tumor tracking. Extensive experiments were performed on a public dataset, showing the validity of the proposed methods.
Article
Purpose To evaluate the accuracy of the robot-assisted computed tomography (CT)-guided coordinate positioning puncture method by phantom and animal experiments. Material and methods In the phantom experiment, seven robot-assisted punctures were made to evaluate the accuracy of the method. In the animal experiment, 18 punctures (nine robotic and nine manual) were made in the livers of nine rabbits. The indicators, such as needle-tract length, angle deviation, puncture accuracy, number of scans required, and radiation exposure dose were compared between manual and robotic punctures. The paired-samples t-test was used for analysis. Results In the phantom experiment, the mean accuracy of seven punctures was 2.67 mm. In the animal experiment, there was no significant difference in needle-tract length (32.58 mm vs. 34.04 mm, p = .606), angle deviation (17.21° vs. 21.23° p = .557) and puncture accuracy (8.42 vs. 8.77 mm, p = .851) between the two groups. However, the number CT scans required (2.44 vs. 3.33, p = .002), and the radiation exposure dose (772.98 vs. 1077.89 mGy/cm, p = .003) were lower in the robot group than in the manual group. Conclusions The coordinate positioning puncture method under robot-assisted CT-guidance can reach an accuracy that is comparable to that of the traditional manual CT-guided puncture method and with fewer CT scanning times accompanied with a lower radiation dosage.
Article
Background: CT-guided tissue sampling is a very effective tool. However, false-negative results are obtained when regions such as necrotic core or surrounding reactive fibrosis and inflammation are sampled. PET/CT-guided sampling can circumvent these limitations. Purpose: The aim of this study was to analyze the effectiveness of PET/CT-guided sampling in patients with at least 1 instance of failed or inconclusive CT-guided procedure and factors determining the accurate sampling and complications. Methods: One hundred eleven patients were prospectively included. After feasibility analysis in a diagnostic F-FDG PET/CT, sampling was performed in 106 patients (45 women, 61 men; mean age, 48.09 ± 15.42 years; biopsy in 80 and fine-needle aspiration cytology [FNAC] in 26 patients), using robotic arm and a lower IV injection dose of 74 to 111 MBq (2-3 mCi) F-FDG. In all patients, final check scans revealed needle at the target site. Using planned needle path as reference, deviations in first check scan were measured. Patient (n = 30) and respiratory motion (n = 57) were also recorded. Results: Accurate lesion targeting was achieved in 81 cases (63 positive lesions, 12 confounding lesions, and 7 inadequate samples). Lesion was missed in 5 instances, and blood/necrotic tissue sampled in 19. Overall F-FDG-avid lesions were accurately targeted in 77.36% of patients (86.25% [biopsy] + 50% [FNAC]). Significant variables affecting targeting were needle gauge, deviation from intended entry point, procedure duration, procedure type, and patient movement. Using binomial regression, the significant parameters were procedure type (biopsy vs FNAC; odds ratio [OR], 5.916; P = 0.002), patient movement (OR, 0.275; P = 0.023), and procedure duration (OR, 1.195; P = 0.011). Overall complication rate was 21.70%, with 4.71% major complications. It was dependent on target depth (mean depth, 69.74 ± 20.29 mm [complications] vs 47.18 ± 22.60 mm; P < 0.001). Positive correlation was seen between the target depth and distance of needle from the intended target (Spearman ρ = 0.307; P = 0.001). In 28 procedures, the physician was asked to wear a pocket dosimeter, who received a mean dose of 2.52 (SD, 3.10) μSv. Conclusions: PET/CT-guided sampling should be considered where CT-guided biopsy has failed or is inconclusive. The outcome is impacted by needle gauge and patient movement, and complication rate is dependent on target depth.
Article
In this paper we present a new robotic device for performing a percutaneous needle biopsy. The device is designed to perform introducer insertion and tissue sampling in organs of interest, such as the lung and liver. It is designed to have smaller parts and better performance than the previous models, and includes light-weight, sensor-based initialization, needle insertion force monitoring, and high performance tissue sampling. With some design improvements, such as a small pillar gear, for needle cartridge rotation, thin side frames, and a kinematic, linkage-based, spring block trigger, the device is over 40% lighter than previous models. Hall sensors mounted on each moving part, and a load cell between a needle insertion part and the frame, provide information for the stable and safe operation of the device. A prototype was fabricated, based on the design model, and the performance was evaluated for the positioning of the part holding the needle and for the tissue sampling. The results show that the device has an average error of less than 0.1 mm and a tissue sampling success rate of 100%, in both ex-vivo and in-vivo experiments.
Article
Background: Robot-assisted puncture has gradually attracted more attention and practical clinical application. The lesion positioning and the needle positioning are the basis to ensure the accuracy of puncture and the key techniques in insertion operation. Methods: A lesion positioning method is established which is realized only by the robot-CT system without using external positioning system, and an omnidirectional needle positioning method is also developed and realized by using VRCM, in order to make the puncture needle always keep pointing to the lesion point. A CT-guided surgical robotic system used for minimally invasive percutaneous lung is designed and the physical prototype is manufactured, to perform in-vitro experiments, thereby to validate the effectiveness of the lesion positioning method and the feasibility of omnidirectional needle positioning method. Results: The accuracy of established lesion positioning method based on three non-collinear markers is within 3 mm, which is similar to that of the least squares method based on the five non-coplanar markers, but the positioning efficiency can be improved by about 40%, and the non-collinearity of markers is easier to be satisfied than non-coplanarity in practical applications. The average calculation error of the established positioning method is 0.997 mm. Moreover, the omnidirectional positioning of the puncture needle under the designed surgical robot is feasible. Conclusions: The designed surgical robot has good control accuracy and it can satisfy the requirements for use. The established lesion positioning method can provide a good precision basis for robot-assisted puncture surgery. The suitable insertion point and insertion posture can be determined by the developed omnidirectional needle positioning method. This work can provide theoretical reference for further study of path planning or autonomous positioning.
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Computed tomography-guided transthoracic needle aspiration (TTNA) and biopsy (TTNB) is a well established, safe, and rapid method of reaching a definitive diagnosis for most thoracic lesions. The present study aimed to determine the roles of TTNA and TTNB in the diagnosis of pulmonary diseases and to compare the results using these two techniques. TTNB and TTNA were performed in 105 patients admitted to our clinic due to peripheral pulmonary lesions between May 2005 and November 2007. Needle biopsies were performed using 18-gauge Tru-Cut® biopsy needles and aspirations was performed using 18-20-22-gauge Chiba needles. Malignant lesions diagnosed by TTNB were non-small cell lung carcinoma (51 patients, 73%), small cell lung carcinoma (nine patients, 13%), malignant tissue (three patients, 5%), lymphoma (two patients, 3%), thymoma (two patients, 3%), plasmacytoma (one patient, 1%), rhabdomyosarcoma (one patient, 1%), and metastasis (one patient, 1%). The malignant lesions diagnosed by TTNA were non-small cell lung carcinoma in eleven patients (92%) and malignant tissue in one patient (8%). Three (100%) of the benign lesions diagnosed by TTNB were granulomas and two (100%) benign lesions diagnosed by TTNA were infarctions. When the diagnostic value of TTNB and TTNA was compared, TTNB was significantly superior. Malignant lesions were identified in 70 (84%) and benign lesions were identified in three (4%) of the 83 patients in the TTNB group. Ten (12%) patients in the TTNB group could not be diagnosed. Malignant lesions were found in 12 (55%) and benign lesions were found in two (9%) of the 22 patients in the TTNA group. Negative results were obtained in eight (36%) patients. The diagnostic sensitivity, specificity, and accuracy of TTNB was calculated to be 92%, 100%, and 93%, respectively (Table 5). The diagnostic sensitivity, specificity, and accuracy of TTNA was 78%, 100%, and 82%, respectively. TTNB had a sensitivity of 92% (70/76) in malignant cases and 100% (3/3) in benign cases, while the sensitivity of TTNA in malignant and benign cases was 75% (3/4) and 67% (2/3), respectively. TTNB is a safe and easy procedure which provides a highly accurate diagnosis of benign and malignant lung lesions without causing a significant increase in complication rates.
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To compare the accuracy of a robotic interventional radiologist (IR) assistance platform with a standard freehand technique for computed-tomography (CT)-guided biopsy and simulated radiofrequency ablation (RFA). The accuracy of freehand single-pass needle insertions into abdominal phantoms was compared with insertions facilitated with the use of a robotic assistance platform (n = 20 each). Post-procedural CTs were analysed for needle placement error. Percutaneous RFA was simulated by sequentially placing five 17-gauge needle introducers into 5-cm diameter masses (n = 5) embedded within an abdominal phantom. Simulated ablations were planned based on pre-procedural CT, before multi-probe placement was executed freehand. Multi-probe placement was then performed on the same 5-cm mass using the ablation planning software and robotic assistance. Post-procedural CTs were analysed to determine the percentage of untreated residual target. Mean needle tip-to-target errors were reduced with use of the IR assistance platform (both P < 0.0001). Reduced percentage residual tumour was observed with treatment planning (P = 0.02). Improved needle accuracy and optimised probe geometry are observed during simulated CT-guided biopsy and percutaneous ablation with use of a robotic IR assistance platform. This technology may be useful for clinical CT-guided biopsy and RFA, when accuracy may have an impact on outcome. • A recently developed robotic intervention radiology assistance platform facilitates CT-guided interventions. • Improved accuracy of complex needle insertions is achievable. • IR assistance platform use can improve target ablation coverage.
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Computed tomography (CT)-compatible robots, both commercial and research-based, have been developed with the intention of increasing the accuracy of needle placement and potentially improving the outcomes of therapies in addition to reducing clinical staff and patient exposure to radiation during CT fluoroscopy. In the case of highly inaccessible lesions that require multiple plane angulations, robotically assisted needles may improve biopsy access and targeted drug delivery therapy by avoidance of the straight line path of normal linear needles. We report our preliminary experience of performing radiofrequency ablation of the liver using a robotic-assisted CT guidance system on 11 patients (17 lesions). Robotic-assisted planning and needle placement appears to have high accuracy, is technically easier than the non-robotic-assisted procedure, and involves a significantly lower radiation dose to both patient and support staff. • An early experience of robotic-assisted radiofrequency ablation is reported • Robotic-assisted RFA improves accuracy of hepatic lesion targeting • Robotic-assisted RFA makes the procedure technically easier with significant lower radiation dose.
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Purpose: Percutaneous lung biopsies (PLBs) performed for the evaluation of pulmonary masses require image guidance to avoid critical structures. A new CT navigation system (SIRIO, "Sistema robotizzato assistito per il puntamento intraoperatorio") for PLBs was validated. Methods: The local Institutional Review Board approved this retrospective study. Image-guided PLBs in 197 patients were performed with a CT navigation system (SIRIO). The procedures were reviewed based on the number of CT scans, patients' radiation exposure and procedural time recorded. Comparison was performed with a group of 72 patients undergoing standard CT-guided PLBs. Sensitivity, specificity and overall diagnostic accuracy were assessed in both groups. Results: SIRIO-guided PLBs showed a significant reduction in procedure time, number of required CT scans and the radiation dose administered to patients ([Formula: see text]). In terms of diagnostic accuracy, SIRIO proved to be more accurate for small-sized lesions ([Formula: see text]20 mm) than standard CT-guidance. Conclusion: SIRIO proved to be a reliable and effective tool when performing CT-guided PLBs and was especially useful for sampling small ([Formula: see text]20 mm) lesions.
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This report is to complement the original Fleischner Society recommendations for incidentally detected solid nodules by proposing a set of recommendations specifically aimed at subsolid nodules. The development of a standardized approach to the interpretation and management of subsolid nodules remains critically important given that peripheral adenocarcinomas represent the most common type of lung cancer, with evidence of increasing frequency. Following an initial consideration of appropriate terminology to describe subsolid nodules and a brief review of the new classification system for peripheral lung adenocarcinomas sponsored by the International Association for the Study of Lung Cancer (IASLC), American Thoracic Society (ATS), and European Respiratory Society (ERS), six specific recommendations were made, three with regard to solitary subsolid nodules and three with regard to multiple subsolid nodules. Each recommendation is followed first by the rationales underlying the recommendation and then by specific pertinent remarks. Finally, issues for which future research is needed are discussed. The recommendations are the result of careful review of the literature now available regarding subsolid nodules. Given the complexity of these lesions, the current recommendations are more varied than the original Fleischner Society guidelines for solid nodules. It cannot be overemphasized that these guidelines must be interpreted in light of an individual's clinical history. Given the frequency with which subsolid nodules are encountered in daily clinical practice, and notwithstanding continuing controversy on many of these issues, it is anticipated that further refinements and modifications to these recommendations will be forthcoming as information continues to emerge from ongoing research.© RSNA, 2012.
Article
The diagnostic yield of computed tomography (CT)-guided biopsies is dependent on accurate needle insertion. A laser-assisted angle selection system was custom fabricated and used during a CT-guided lung biopsy. Off-target error was measured comparing standard methods to the laser method while pointing towards the target from the skin. The difference between the planned angle and selected angle using the laser-assisted system was 2°, improved from 12° with the standard method. Although yet to be confirmed, laser-assisted angle selection systems may improve the accuracy of needle placement, which may translate into improved outcomes for certain needle based procedures.
Article
The objective of this article is to update previous evidence-based recommendations for evaluation and management of individuals with solid pulmonary nodules and to generate new recommendations for those with nonsolid nodules. We updated prior literature reviews, synthesized evidence, and formulated recommendations by using the methods described in the "Methodology for Development of Guidelines for Lung Cancer" in the American College of Chest Physicians Lung Cancer Guidelines, 3rd ed. We formulated recommendations for evaluating solid pulmonary nodules that measure > 8 mm in diameter, solid nodules that measure ≤ 8 mm in diameter, and subsolid nodules. The recommendations stress the value of assessing the probability of malignancy, the utility of imaging tests, the need to weigh the benefits and harms of different management strategies (nonsurgical biopsy, surgical resection, and surveillance with chest CT imaging), and the importance of eliciting patient preferences. Individuals with pulmonary nodules should be evaluated and managed by estimating the probability of malignancy, performing imaging tests to better characterize the lesions, evaluating the risks associated with various management alternatives, and eliciting their preferences for management.
Article
The novel optical tracking system employs a miniature video camera, mounted on the hub of an interventional needle, to determine the location and orientation of the needle relative to a skin-attached sticker with color reference markers. A computed tomography (CT) scan is used to register the same reference markers to the anatomy in the CT images, and thus, register the needle to the anatomy and to a user-selected target. A computer displays a simulation of the interventional needle on the CT images, providing guidance information to assist a user in directing the needle to the target. Bench testing was performed on a custom phantom to determine the accuracy of this minioptical tracking system. The resulting accuracy data demonstrates a good correlation with phantom coordinates and the CT images.