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

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

Total laparoscopic resection by medial-retroperitoneal approach using virtual navigation: two case reports of primary retroperitoneal schwannoma

Background We report two rare cases of retroperitoneal schwannoma completely resected by a laparoscopic medial-retroperitoneal approach aided by virtual navigation. Three-dimensional images have been used in liver and lung surgery, but there are few prior reports on retroperitoneal surgery. Case presentation These two case reports are of a 60-year-old man and a 40-year-old man with asymptomatic retroperitoneal schwannoma. In both cases, the tumors were located in the right renal hilum and were close to the duodenum, right ureter, and inferior vena cava. Simulation using three-dimensional images was performed before surgery, and a medial-retroperitoneal approach was performed to secure a wide surgical field. During the operation, we confirmed the location of the main feeder and the relationship between the tumor and organs with those shown on the three-dimensional images and performed total laparoscopic resection. Conclusion The medial-retroperitoneal approach provides operative safety. Preoperative simulation and intraoperative navigation with three-dimensional images, which can be freely rotated and interactively visualized from any angle, are useful methods to enhance the surgeon’s understanding of a patient’s specific anatomy and are especially effective when resecting a retroperitoneal tumor that is located in an anatomically deep and complex location.

Total Laparoscopic Resection by Retroperitoneal Approach Using Virtual Navigation: Two Case Reports of Primary Retroperitoneal Schwannoma

Background: We report two rare cases of retroperitoneal schwannoma completely resected by laparoscopic retroperitoneal approach aided by virtual navigation.Case presentation: These two case reports are of a 60‐year‐old man and a 40‐year‐old man with asymptomatic retroperitoneal schwannoma. In both cases, the tumors were located in the right renal hilum and were close to the duodenum, right ureter, and inferior vena cava. Simulation using three-dimensional images was performed before surgery, and a retroperitoneal approach was performed to secure a wide surgical field. During the operation, we confirmed the location of the main feeder and the relationship between the tumor and organs with those shown on the three-dimensional images and performed total laparoscopic resection.Conclusion: The retroperitoneal approach provides operative safety. Preoperative simulation and intraoperative navigation with three-dimensional images are useful methods to enhance the surgeon’s understanding of a patient’s specific anatomy and are especially effective when resecting a retroperitoneal tumor that is located in an anatomically deep and complex location.

INVESTIGATION OF THE UNDERGROUND BUILDING HERITAGE AND THE MECHANISM OF WATER FLOWING IN <i>QANĀTS</i> IN PALERMO THROUGH INNOVATIVE SURVEYING TECHNIQUES

The valorisation, protection and preservation policies for the underground building heritage are often difficult to implement due to an inadequate knowledge of hypogeal constructions. The complex and widespread underground structures of the vast “Cavo” Heritage (“horizontal wells”, “shelf wells” or “well tunnels”), so called qanāts, hidden underground and built over the centuries in Palermo, representing an evocative testimony to the history of water culture in the ancient city. Through the historical and constructive analyses and the implementation and development of measurement and 3D representation and visualization, first actions have been carried out. The paper will present the first results of the restoration project and the path of re-introduction in the fruition network of the qanāt “Gesuitico alto”, developed also in the field of “iHeritage. Mediterranean Platform for UNESCO Cultural Heritage” project, financed by ENI CBC MED Programme 2014–2020. The paper presents an experimentation of a procedural workflow of data acquisition, analysis and subsequent 3D virtual navigation of hypogeal environments. The methodology used is the SLAM with a last generation WMLS. The platform of virtual reality visualization, within UnReal Engine, allows the user to immerse and navigate in the anthropic environment by engaging it with a set of infographics that highlight the virtual visit.

P–334 CT virtual Histerotomography: a new method for the evaluation of fallopian tube patency and pelvic organs in patients seeking pregnancy

Study question Can computerized virtual histerotomography (CT-HSG) be used for the evaluation of fallopian tube patency and pelvic organs in patients seeking pregnancy? Summary answer: CT-HSG seems to be an adequate test for the evaluation of fallopian tube patency, pelvic organs, and the uterine cavity. What is known already CT-HSG is a minimally invasive exam, which diagnoses variations in the female reproductive system, uses low radiation doses and is well tolerated by patients. It simultaneously evaluates the uterine wall, cavity and cervix, tubes, and adjacent pelvic structures. The exam enables virtual navigation, which consists of the endoluminal view of the cervical canal and uterine cavity and allows 3D reconstruction of images. The exam remains underused to assess infertility, but previous studies have shown potential and its use may be widespread. Study design, size, duration Retrospective cohort study, that included data from 317 women seeking pregnancy, between January/2019 and January/2021. The CT-HSG was indicated for infertility (90.3%) and RPL (0.9%) investigation, and for the evaluation of tubal stump in patients who were planning the tubal reversal surgery (8.8%). Patients filled out a questionnaire about their pain symptoms and data were collected from electronic records. Participants/materials, setting, methods The study analyzed patients’ clinical characteristics and image findings regarding tubes, uterine cavity, and ovaries. For the exam, a catheter was positioned in the cervix, where the contrast medium (iopromide) was injected through an infusion pump at 0.30 ml/s, for a total of 20ml. The tomographic slices were obtained at the 50th second. The CT-HSG images were interpreted by the same gynecologist and radiologist. Data were analyzed using SPSS version 20.0. Main results and the role of chance Women and partners’ mean age was 32.7 ± 5.6 and 34.6 ± 7.7 years, respectively, and women’s mean BMI was 28.4 ± 6.4 Kg/m². The pain scale was applied in 103 patients, who reported 5.4±3.2 pain scale scores at the end of the exam. Among the infertile patients 67% were nulliparous. Regarding the exam findings, most of the uterus findings were normal (72.6%). The variations found were uterine malformations (including unicornuate uterus, uterus didelphys, bicornuate uterus, septate uterus, and arcuate uterus), synechia, fibroids, endometrial polyps, adenomyosis and retractions/lateralizations that may suggest endometriosis. The tubal findings on the right/left (%) were: 65/67.5 patent horn; 18.9/17.7 obstructed tubes; 4/41 dilatation/hydrosalpinx and 9.4/9.1 with previous history of tubal ligation or salpingectomy; 1.5% of the tubal evaluation were inconclusive. Eleven from 317 patients had to repeat the exam due to occurrences during the execution (for example, improper catheter positioning, cuff fall, stenosis of the internal cervical ostium, severe pain).The 3D analysis and virtual navigation assist in the findings assessment, in addition to being simpler for the gynecologists evaluation. Limitations, reasons for caution The sample size is small due to the exam being a new technique. Patient follow-up and correlation with laparoscopy and hysteroscopy, when indicated, are under studied. Wider implications of the findings: The exam seems to be promising for assessing infertility, RPL and the tubal stump. Moreover, it may be a good option to hysterosalpingography as it seems to cause less pain and allows to evaluate the ovaries and the uterine contour, added to 3D reconstructions and to virtual uterine navigation. Trial registration number Not applicable