Safety, quality and efficiency of intra-operative imaging for treatment decisions in patients with suspected choledocholithiasis without pre-operative magnetic resonance cholangiopancreatography.

INTRODUCTION: Cholecystectomy is the accepted treatment for patients with symptomatic gallstones. In this study, we evaluate a simplified strategy for managing suspected synchronous choledocholithiasis by focussing on intra-operative imaging as the primary decision-making tool to target common bile duct (CBD) stone treatment. METHODS: All elective and emergency patients undergoing laparoscopic cholecystectomy (LC) for gallstones with any markers of synchronous choledocholithiasis were included. Patients unfit for surgery or who had pre-operative proof of choledocholithiasis were excluded. Intra-operative imaging was used for evaluation of the CBD. CBD stone treatment was with bile duct exploration (LCBDE) or endoscopic retrograde cholangiopancreatography (LC + ERCP). Outcomes were safety, effectiveness and efficiency. RESULTS: 506 patients were included. 371 (73%) had laparoscopic ultrasound (LUS), 80 (16%) had on-table cholangiography (OTC) and 55 (11%) had both. 164 (32.4%) were found to have CBD stones. There was no increase in length of surgery for LC + LUS compared with average time for LC only in our unit (p = 0.17). 332 patients (65.6%) had clear ducts. Imaging was indeterminate in 10 (2%) patients. Overall morbidity was 10.5%. There was no mortality. 142 (86.6%) patients with stones on intra-operative imaging proceeded to LCBDE. 22 (13.4%) patients had ERCP. Sensitivity and specificity of intra-operative imaging were 93.3 and 99.1%, respectively. Success rate of LCBDE was 95.8%. Effectiveness was 97.8%. CONCLUSIONS: Eliminating pre-operative bile duct imaging in favour of intra-operative imaging is safe and effective. When combined with intra-operative stone treatment, this method becomes a true 'single-stage' approach to managing suspected choledocholithiasis.

The Portsmouth protocol for intra-operative ultrasound of the small bowel in Crohn's disease.

AIM: Bowel preservation is paramount in Crohn's disease surgery as affected patients are typically young adults at risk of having several abdominal surgical procedures during their lifetime. Intra-operative assessment of the extent and location of Crohn's disease is not standardized and is left to a mixture of the surgeon's experience, tactile feedback, macroscopic appearance and preoperative imaging. The aim of this study was to describe the technical steps of a standardized protocol for intra-operative ultrasound assessment of the small bowel in patients undergoing surgery for ileocolic Crohn's disease. METHOD: After laparoscopic mobilization of the bowel, a periumbilical incision is performed for extracorporeal division of the mesentery and the resection and anastomosis. A gastrointestinal consultant radiologist, with expertise in Crohn's disease imaging and abdominal ultrasound, performs full intra-operative assessment of the small bowel by applying a sterile ultrasound probe directly to the bowel, prior to resection being performed by the surgeon. The bowel is assessed through the wound protector with a sterile technique and the length, location and number of segments is documented together with further quantitative assessment using the METRIC (MR enterography or ultrasound in Crohn's disease) scoring guide. RESULTS: A step-by-step protocol for intra-operative ultrasound evaluation of the entire small bowel is described. CONCLUSIONS: A standardized approach to intra-operative evaluation of the extent and location of Crohn's disease is desirable. Intra-operative ultrasound may provide added value for assessment of proximal and multifocal Crohn's disease.

Robotic-assisted surgery for colorectal liver metastasis: A single-centre experience.

Background: Although minimally invasive surgery (MIS) of the liver is increasingly widespread, its role in the treatment of colorectal liver metastasis (CRLM) remains uncertain. In this setting, the role of robotic-assisted surgery (RAS) has not been significantly evaluated yet. The aim of this study was to report our experience with RAS for treatment of CRLM. Material and Methods: Prospectively collected surgical and oncologic data on all of the robotic-assisted liver resections for CRLM performed at our centre were retrieved from the institutional database and retrospectively analysed. Intra-operative ultrasound (US) was obtained with a dedicated robotic probe using the TilePro™ function. Results: Twenty patients underwent robotic-assisted resection of CRLM between May 2012 and April 2018. Six patients (30%) had multiple synchronous CRLM resections (median = 2; range 2-4). The tumour size averaged 3.0 ± 1.8 cm. All of the lesions were removed using a parenchymal-sparing approach, with R0 resection margins. Mean hospital stay was 4.7 ± 1.8 days. The mean follow-up was 22.5 ± 19.5 months. During the study period, there were no local recurrences, while 9 patients (45%) developed new systemic metastasis. All patients are still alive as of September 2018 with 1- and 3-year disease-free survival of 89.5% and 35.8%, respectively. Conclusions: In our experience, RAS for CRLM surgical treatment was feasible and played a positive role even in patients with multiple metastases and previous or synchronous surgery. RAS seemed to be oncologically effective in this setting, as no patients experienced local relapse in the treated area.

Does intra-operative margin assessment improve margin status and re-excision rates? A population-based analysis of outcomes in breast-conserving surgery for ductal carcinoma in situ.

BACKGROUND AND OBJECTIVES: Using a 2 mm margin criteria, we evaluated the effect of intra-operative margin assessment on margin status and re-excisions following breast-conserving surgery (BCS) for ductal carcinoma in situ (DCIS). METHODS: We identified patients undergoing BCS for DCIS from a prospective, population-based database. Multivariable logistic regression was used to determine the effect of specimen mammography, ultrasound and macroscopic assessment by a pathologist on margins and re-excision rates. RESULTS: In 588 patients, 52% (95% confidence interval [CI], 48%-56%) had positive margins (<2 mm), 39% (95% CI, 35%-43%) had a re-excision and 15% (95% CI, 12%-18%) had completion mastectomy. There were few re-excisions for margins ≥2 mm (2%). Adjusting for confounders, any margin assessment versus wire localization alone did not reduce positive margins (odds ratio [OR], 0.75; P = 0.202) or re-excisions (OR, 1.14; P = 0.564), however both outcomes varied by type of technique ( P < 0.001). Individually, only macroscopic assessment by pathologist reduced positive margins (OR, 0.54; P = 0.002) and re-excisions (OR, 0.61; P = 0.036). CONCLUSIONS: Despite adherence to a 2 mm margin criteria, re-excision rates remain high following BCS for DCIS, with 39% converted to mastectomy when re-excision is required. Intra-operative margin assessment does not appear to reduce re-excisions; in particular, surgeons should be aware of the limitations of specimen mammography for margin assessment in DCIS.

Autonomous control of an ultrasound probe for intra-operative ultrasonography using vision-based shape sensing of pneumatically attachable flexible rails.

PURPOSE: In robotic-assisted minimally invasive surgery, surgeons often use intra-operative ultrasound to visualise endophytic structures and localise resection margins. This must be performed by a highly skilled surgeon. Automating this subtask may reduce the cognitive load for the surgeon and improve patient outcomes. METHODS: We demonstrate vision-based shape sensing of the pneumatically attachable flexible (PAF) rail by using colour-dependent image segmentation. The shape-sensing framework is evaluated on known curves ranging from r = 30 to r = 110 mm, replicating curvatures in a human kidney. The shape sensing is then used to inform path planning of a collaborative robot arm paired with an intra-operative ultrasound probe. We execute 15 autonomous ultrasound scans of a tumour-embedded kidney phantom and retrieve viable ultrasound images, as well as seven freehand ultrasound scans for comparison. RESULTS: The vision-based sensor is shown to have comparable sensing accuracy with FBGS-based systems. We find the RMSE of the vision-based shape sensing of the PAF rail compared with ground truth to be 0.4975 ± 0.4169 mm. The ultrasound images acquired by the robot and by the human were evaluated by two independent clinicians. The median score across all criteria for both readers was '3-good' for human and '4-very good' for robot. CONCLUSION: We have proposed a framework for autonomous intra-operative US scanning using vision-based shape sensing to inform path planning. Ultrasound images were evaluated by clinicians for sharpness of image, clarity of structures visible, and contrast of solid and fluid areas. Clinicians evaluated that robot-acquired images were superior to human-acquired images in all metrics. Future work will translate the framework to a da Vinci surgical robot.

Cystic Echinococcosis of the Liver: Correlation Between Intra-Operative Ultrasound and Pre-Operative Imaging.

Background: Imaging plays an essential role in the management of hepatic hydatid cysts (HCE). The objective of our study was to determine the correlation between pre-operative ultrasound, computed tomography (CT), and intra-operative ultrasound (IOUS) in studying the characteristics and complications of HCE. Patients and Methods: This was a prospective, descriptive, and analytical study conducted in the General Surgery Department of Habib Bourguiba Hospital in Sfax. The study included patients with HCE who underwent conservative surgery between April 2017 and June 2022. Results: We enrolled 49 patients with 94 cysts. At the end of our study, IOUS allowed for better detection of HCE (98.8%) regardless of the number of cysts per patient. IOUS and CT were accurate in studying the location of cysts (κ = 1), whereas pre-operative abdominal ultrasound was less efficient (κ = 0.870). IOUS was the best examination for detecting exocysts (κ = 0.961), studying daughter cysts (κ = 0.823), and exploring vascular relations, but it was less effective (κ = 0.523) in detecting calcifications. Regarding classifications, ultrasound and CT had similar results. However, IOUS was most reliable in differentiating between CE3b and CE4 types (κ = 0.653). Ultrasound, CT, and IOUS were not sensitive in detecting latent HCE suppurations and cystobiliary fistulas. Conclusions: Performing IOUS is essential to prevent recurrences and reduce post-operative morbidity.

Second-trimester dilatation and evacuation: Comparison of routine intraoperative ultrasonography versus problem-based intraoperative ultrasonography in reducing procedure-related complications: A pre-post study.

OBJECTIVE: To investigate whether routine intraoperative ultrasonographic guidance during second-trimester dilatation and evacuation (D&E) reduces procedure-related complications in an Ethiopian setting. METHODS: We conducted a pre-post study on routine ultrasonography during second-trimester D&E at St. Paul's Hospital Millennium Medical College (Ethiopia). Second-trimester D&E cases that were managed at the hospital between 2017 and 2022 were retrospectively analyzed by grouping them into an intervention group (using routine ultrasound intraoperatively for all cases) and a non-intervention group (problem-based intraoperative use of ultrasound, where ultrasound was used in problem cases only). SPSS version 23 was used for analysis and simple descriptive statistics, χ2 test, multivariate regression analysis, and Fisher exact test were performed as appropriate. P values less than 0.05 and odds ratio with 95% CI were used to present the results' significance. RESULTS: A total of 242 second-trimester D&E cases were analyzed (84 cases managed under routine intraoperative ultrasound guidance and 158 cases managed with a problem-based intraoperative use of ultrasound). Compared with problem-based intraoperative use of ultrasound (using it only in selected cases), routine intraoperative ultrasound use was not associated with a decrease in D&E complications (adjusted odds ratio [aOR] 0.22, 95% confidence interval [CI] 0.04-1.16). The two factors associated with increased D&E procedure complications were advanced gestational age (aOR 13.52, 95% CI 1.86-98.52), and need for additional mechanical cervical dilatation during the D&E procedure (aOR 9.53, 95% CI 1.32-69.07). Provider experience, cervical preparation methods (laminaria vs Foley), and maternal age were not associated with occurrence of D&E complications. CONCLUSION: Our study does not support the preference of routine intraoperative ultrasound guidance over problem-based (in selected cases) intraoperative ultrasound use during the second-trimester D&E procedure. More research is needed to make a strong clinical recommendation on using routine intraoperative ultrasound guidance during all second-trimester D&E procedures.

Intraoperative Ultrasound in Minimally Invasive Laparoscopic and Robotic Pediatric Surgery: Our Experiences and Literature Review.

Ultrasound (US) is a non-invasive imaging technique frequently used to examine internal organs and superficial tissues, and invaluable in pediatric patients. In a surgical setting, intraoperative ultrasound allows to highlight anatomical structures in detail during traditional open and minimally invasive surgery, thanks to the use of specific probes. In fact, laparoscopic and robotic ultrasonography requires the development of specialized transducers that fit through laparoscopic trocars. In adults, laparoscopic ultrasound is used during cholecystectomy before dissection of the triangle of Calot, to guide liver biopsies and ablation procedures and for the staging of patients with pancreas adenocarcinoma. However, the applications in the pediatric field are still limited. This paper aims to share our preliminary experience with ultra-sound in minimally invasive laparoscopic and robotic pediatric surgery, describing two cases in which intra-operative ultrasound was applied, and to present a review of the literature on the state of the art of the actual uses in pediatric surgery.

Robust landmark-based brain shift correction with a Siamese neural network in ultrasound-guided brain tumor resection.

PURPOSE: In brain tumor surgery, tissue shift (called brain shift) can move the surgical target and invalidate the surgical plan. A cost-effective and flexible tool, intra-operative ultrasound (iUS) with robust image registration algorithms can effectively track brain shift to ensure surgical outcomes and safety. METHODS: We proposed to employ a Siamese neural network, which was first trained using natural images and fine-tuned with domain-specific data to automatically detect matching anatomical landmarks in iUS scans at different surgical stages. An efficient 2.5D approach and an iterative re-weighted least squares algorithm are utilized to perform landmark-based registration for brain shift correction. The proposed method is validated and compared against the state-of-the-art methods using the public BITE and RESECT datasets. RESULTS: Registration of pre-resection iUS scans to during- and post-resection iUS images were executed. The results with the proposed method shows a significant improvement from the initial misalignment ([Formula: see text]) and the method is comparable to the state-of-the-art methods validated on the same datasets. CONCLUSIONS: We have proposed a robust technique to efficiently detect matching landmarks in iUS and perform brain shift correction with excellent performance. It has the potential to improve the accuracy and safety of neurosurgery.

Left Anterior Sectorectomy: An Alternative to Left Hepatectomy for Tumors Invading the Distal Part of the Left Portal Vein.

BACKGROUND: Liver tumors invading the distal part of the umbilical portion of the left portal vein usually require left hepatectomy. The recent introduction of the concept of left anterior sector, an independent anatomo-functional unit including the anterior portion of the left liver and supplied by the distal part of the umbilical portion of the left portal vein, could represent the rational for an alternative surgical approach. The aim of this study was to introduce the novel surgical procedure of ultrasound-guided left anterior sectorectomy. METHODS: Among 92 consecutive patients who underwent hepatectomy, 3 patients with tumor invading the distal part of the umbilical portion of the left portal (two with colorectal liver metastases and one with neuroendocrine tumor liver metastases) underwent left anterior sectorectomy alone or in association with liver multiple metastasectomies. RESULTS: Mean operation time was 393 min; post-operative morbidity and mortality were not observed. After a mean FU of 23 months (range 19-28), no local recurrence occurred. CONCLUSIONS: In presence of tumors invading the distal part of the umbilical portion of the left portal, left anterior sectorectomy could be considered as an anatomic radical surgical option that is safe but more conservative than a left hepatectomy.

Horseshoe hepatectomy : Another step pursuing the concept of parenchyma sparing major hepatectomies.

We describe a case of complex parenchyma-sparing hepatectomy for multiple bilobar colorectal liver metastases. A 66-years-old male, who previously received a diagnosis of a stenosing adenocarcinoma of the hepatic flexure and synchronous bilobar liver metastases, was referred to our hospital. At the time of the presentation of the disease, a contrast-enhanced CT scan showed 24 liver lesions, with a bilobar distribution and two major cluster of lesions in segment 6 and 7. After neoadjuvant chemotherapy, global partial response, with complete response for most lesions, was detected: seven lesions were visible after re-staging. Surgical strategy was planned by means of three-dimensional reconstruction and simulation software. A unique transection plane comprising partial resection of segments 2, 3, 4, 5 and 8 and complete resection of segments 6 and 7 was performed. Left, middle and right hepatic veins were exposed on the cut surface. Accurate preoperative planning and intraoperative ultrasound for resection guidance allowed us to follow complex transection planes and treat a patient with a high burden of bilobar deeply located disease in a parenchymal-sparing perspective.

Fertility Sparing Surgery and Borderline Ovarian Tumours.

To determine the oncological outcomes following fertility-sparing surgery (FSS) for the management of Borderline Ovarian Tumours (BOTs). A retrospective analysis of participants diagnosed with BOTs between January 2004 and December 2020 at the West London Gynaecological Oncology Centre was conducted. A total of 172 women were diagnosed; 52.3% (90/172) underwent FSS and 47.7% (82/172) non-FSS. The overall recurrence rate of disease was 16.9% (29/172), of which 79.3% (23/29) presented as the recurrence of serous or sero-mucinous BOTs and 20.7% (6/29) as low-grade serous carcinoma (LGSC). In the FSS group, the recurrence rate of BOTs was 25.6% (23/90) presenting a median 44.0 (interquartile range (IQR) 41.5) months, of which there were no episodes of recurrence presenting as LGSC reported. In the non-FSS group, all recurrences of disease presented as LGSC, with a rate of 7.7% (6/78), following a median of 47.5 months (IQR 47.8). A significant difference between the type of surgery performed (FSS v Non-FSS) and the association with recurrence of BOT was observed (Pearson Chi-Square: p = 0.000; x = 20.613). Twelve women underwent ultrasound-guided ovarian wedge resection (UGOWR) as a novel method of FSS. Recurrence of BOT was not significantly associated with the type of FSS performed (Pearson Chi- Square: x = 3.166, p = 0.379). Non-FSS is associated with negative oncological outcomes compared to FSS, as evidenced by the higher rate of recurrence of LGSC. This may be attributed to the indefinite long-term follow up with ultrasound surveillance all FSS women undergo, enabling earlier detection and treatment of recurrences.

The Value of Intraoperative Ultrasound in Selective Lateral Cervical Neck Lymphadenectomy for Papillary Thyroid Cancer: A Prospective Pilot Study.

(1) Background: Lymph node metastases from papillary thyroid cancer (PTC) are frequent. Selective neck dissection (SND) is indicated in PTC with clinical or imaging evidence of lateral neck nodal disease. Both preoperative ultrasound (PreUS) and intraoperative palpation or visualization may underestimate actual lateral neck nodal involvement, particularly for lymph-nodes located behind the sternocleidomastoid muscle, where dissection may also potentially increase the risk of postoperative complications. The significance of diagnostic IOUS in metastatic PTC is under-investigated. (2) Methods: We designed a prospective diagnostic study to assess the diagnostic accuracy of IOUS compared to PreUS in detecting metastatic lateral neck lymph nodes from PTC during SND. (3) Results: There were 33 patients with preoperative evidence of lateral neck nodal involvement from PTC based on PreUS and fine-needle cytology. In these patients, IOUS guided the excision of additional nodal compartments that were not predicted by PreUS in nine (27.2%) cases, of which eight (24.2%) proved to harbor positive nodes at pathology. The detection of levels IIb and V increased, respectively, from 9% (PreUS) to 21% (IOUS) (p < 0.0001) and from 15% to 24% (p = 0.006). (4) Conclusions: In the context of this study, IOUS showed higher sensitivity and specificity than PreUS scans in detecting metastatic lateral cervical nodes. This study showed that IOUS may enable precise SND to achieve oncological radicality, limiting postoperative morbidity.

Comparative analysis of active contour and convolutional neural network in rapid left-ventricle volume quantification using echocardiographic imaging.

In cardiology, ultrasound is often used to diagnose heart disease associated with myocardial infarction. This study aims to develop robust segmentation techniques for segmenting the left ventricle (LV) in ultrasound images to check myocardium movement during heartbeat. The proposed technique utilizes machine learning (ML) techniques such as the active contour (AC) and convolutional neural networks (CNNs) for segmentation. Medical experts determine the consistency between the proposed ML approach, which is a state-of-the-art deep learning method, and the manual segmentation approach. These methods are compared in terms of performance indicators such as the ventricular area (VA), ventricular maximum diameter (VMXD), ventricular minimum diameter (VMID), and ventricular long axis angle (AVLA) measurements. Furthermore, the Dice similarity coefficient, Jaccard index, and Hausdorff distance are measured to estimate the agreement of the LV segmented results between the automatic and visual approaches. The obtained results indicate that the proposed techniques for LV segmentation are useful and practical. There is no significant difference between the use of AC and CNN in image segmentation; however, the AC method could obtain comparable accuracy as the CNN method using less training data and less run-time.

Contrast-Enhanced Ultrasound Assisted Surgery of Intramedullary Spinal Cord Tumors: Analysis of Technical Benefits and Intra-operative Microbubble Distribution Characteristics.

Intra-operative contrast-enhanced ultrasound (CEUS) is a relatively standardized procedure in brain neurosurgery, but it is still underused in spinal cord and intramedullary tumor evaluation. We reviewed and analyzed the intra-operative data from a surgical series of patients harboring intramedullary spinal cord tumors who underwent surgery under CEUS guidance. CEUS was performed in 12 patients (age range: 13-55 y); all lesions had ill-defined boundaries or peritumoral cysts at preliminary intra-operative B-mode ultrasound. CEUS highlighted the tumors in all cases. The contrast agent's spinal distribution revealed different phases (arterial, peak, washout), as observed in the brain, but these appeared to be slower and less intense. In our experience, intra-operative CEUS allows surgeons to assess spinal cord perfusion and highlight intramedullary tumors in real time. As for other imaging modalities, ultrasound contrast agents add valuable information over baseline imaging, and their use should be fostered to better understand microbubble distribution dynamics.

Brain Shift in Neuronavigation of Brain Tumors: An Updated Review of Intra-Operative Ultrasound Applications.

Neuronavigation using pre-operative imaging data for neurosurgical guidance is a ubiquitous tool for the planning and resection of oncologic brain disease. These systems are rendered unreliable when brain shift invalidates the patient-image registration. Our previous review in 2015, Brain shift in neuronavigation of brain tumours: A review offered a new taxonomy, classification system, and a historical perspective on the causes, measurement, and pre- and intra-operative compensation of this phenomenon. Here we present an updated review using the same taxonomy and framework, focused on the developments of intra-operative ultrasound-based brain shift research from 2015 to the present (2020). The review was performed using PubMed to identify articles since 2015 with the specific words and phrases: "Brain shift" AND "Ultrasound". Since 2015, the rate of publication of intra-operative ultrasound based articles in the context of brain shift has increased from 2-3 per year to 8-10 per year. This efficient and low-cost technology and increasing comfort among clinicians and researchers have allowed unique avenues of development. Since 2015, there has been a trend towards more mathematical advancements in the field which is often validated on publicly available datasets from early intra-operative ultrasound research, and may not give a just representation to the intra-operative imaging landscape in modern image-guided neurosurgery. Focus on vessel-based registration and virtual and augmented reality paradigms have seen traction, offering new perspectives to overcome some of the different pitfalls of ultrasound based technologies. Unfortunately, clinical adaptation and evaluation has not seen as significant of a publication boost. Brain shift continues to be a highly prevalent pitfall in maintaining accuracy throughout oncologic neurosurgical intervention and continues to be an area of active research. Intra-operative ultrasound continues to show promise as an effective, efficient, and low-cost solution for intra-operative accuracy management. A major drawback of the current research landscape is that mathematical tool validation based on retrospective data outpaces prospective clinical evaluations decreasing the strength of the evidence. The need for newer and more publicly available clinical datasets will be instrumental in more reliable validation of these methods that reflect the modern intra-operative imaging in these procedures.

Uniportal video assisted thoracoscopy versus open surgery for pulmonary hydatid disease-a single center experience.

BACKGROUND: Although rare in the Western world, the incidence of hydatid disease is still prevalent and strikingly endemic among the Palestinians. Until 2017, surgical treatment of lung pathologies was performed through the traditional incision (open thoracotomy). Uniportal video-assisted thoracoscopic surgery (VATS) approach has recently been applied in the cases of the pulmonary hydatid cysts with very satisfactory results. METHODS: Between January 2010 and January 2019, 39 patients with pulmonary HC disease have been surgically treated. The cases divided into two cohorts: operations performed by thoracotomy classified as group A, (n=16). Operations performed by uniportal VATS classified as group B, (n=23). Prospectively collected data was analysed retrospectively, and the results compared between both groups. RESULTS: No significant statistical differences were noticed in terms of demographics and comorbidity. Laboratory tests were similar except haemoglobin level, which was higher in group A (P=0.001). Despite that, blood transfusion was higher in group A (P=0.016). Moreover, operation time was longer in group A (P=0.000). Chest drainage remained longer in group A (P=0.077). The level of postoperative pain was significantly higher in group A certainly in POD 1 (P=0.000). Patients in group B discharged earlier from the hospital (P=0.011) and experienced lower complications (P=0.060). No significant difference in length of ICU stay. Neither recurrence nor 30-day mortality recorded in either group. CONCLUSIONS: Uniportal VATS can be safely applied for pulmonary hydatidosis. It also seems to have a preference in several aspects compared to open Thoracotomy approach.

Automatic and efficient MRI-US segmentations for improving intraoperative image fusion in image-guided neurosurgery.

Knowledge of the exact tumor location and structures at risk in its vicinity are crucial for neurosurgical interventions. Neuronavigation systems support navigation within the patient's brain, based on preoperative MRI (preMRI). However, increasing tissue deformation during the course of tumor resection reduces navigation accuracy based on preMRI. Intraoperative ultrasound (iUS) is therefore used as real-time intraoperative imaging. Registration of preMRI and iUS remains a challenge due to different or varying contrasts in iUS and preMRI. Here, we present an automatic and efficient segmentation of B-mode US images to support the registration process. The falx cerebri and the tentorium cerebelli were identified as examples for central cerebral structures and their segmentations can serve as guiding frame for multi-modal image registration. Segmentations of the falx and tentorium were performed with an average Dice coefficient of 0.74 and an average Hausdorff distance of 12.2 mm. The subsequent registration incorporates these segmentations and increases accuracy, robustness and speed of the overall registration process compared to purely intensity-based registration. For validation an expert manually located corresponding landmarks. Our approach reduces the initial mean Target Registration Error from 16.9 mm to 3.8 mm using our intensity-based registration and to 2.2 mm with our combined segmentation and registration approach. The intensity-based registration reduced the maximum initial TRE from 19.4 mm to 5.6 mm, with the approach incorporating segmentations this is reduced to 3.0 mm. Mean volumetric intensity-based registration of preMRI and iUS took 40.5 s, including segmentations 12.0 s.

Surgeon-led Intraoperative Ultrasound Localization for Nonpalpable Breast Cancers: Results of 5 Years of Practice.

BACKGROUND: The uptake of breast screening has led to a rise in the number of nonpalpable breast cancer diagnoses. Breast conserving therapy (BCT) is the treatment of choice for early breast cancer, and this requires localization of the lesion. Commonly detection is achieved by wire-guided localization in the radiology department. This technique has complications and requires utilization of a radiologist. Intraoperative ultrasound (IOUS) has been shown to be a safe alternative, but there is little data on its use. The aim of this study is to report the use of surgeon-led IOUS over the past 5 years, assessing the ability to detect lesions and the re-excision rate for involved margins. PATIENTS AND METHODS: A retrospective observational study was performed on consecutive patients undergoing IOUS-marked BCT between 2014 and 2018. The technique is described, and patients' records were reviewed to assess the histologic specimen reports and need for subsequent re-excision. RESULTS: Ninety-five IOUS BCT operations were performed. Every cancer was identified by IOUS and removed. Fourteen margins were positive and required re-excision. Of these, only 2 contained residual tumor. CONCLUSION: This is the first data from the United Kingdom for IOUS skin marking without wire localization. IOUS is a safe method of localization in BCT. It offers advantages both to the patient and the unit as it reduces pressure on the radiology department.

Pre-, intra-, and postoperative management of Robert's uterus.

OBJECTIVES: To demonstrate a minimally invasive approach and management in three different types of Robert's uterus. DESIGN: Video presentation of surgical and ultrasound techniques. SETTING: University hospital and two private centers. PATIENTS: Patients with three types of Robert's uterus; a rare form of septate uterus consisting of non-communicating hemicavity, a contralateral unicornuate uterine cavity in a single uterine body with normal fundus: with large hematometra in the blind hemi-cavity and acute pelvic pain; with an inactive blind hemi-cavity without hematometra and recurrent miscarriages; and with small hematometra in the blind hemi-cavity. INTERVENTIONS: Three-dimensional ultrasound with saline infusion sonohysterography and automatic volume calculation software (SonoHySteroAVC) were used for differential diagnosis and surgical planning. Transrectally guided hysteroscopic metroplasty, a incision of myometrium between two parts of cavities by resectoscope and Collin's electrode, were performed and recorded. Sequentional balloon anti-adhesion therapy and three-dimensional ultrasound with saline infusion sonohysterography with SonoHysteroAVC were used in post-operative management. MAIN OUTCOME MEASURES: Pre-, intra- and postoperative findings regarding uterine morphology, feasibility of surgery and anatomical and clinical outcomes. RESULTS: A successful unification of non-communicating and communicating uterine cavity parts during surgery, better shape and several times higher volume of uterine cavity, and total elimination of pain associated with obstruction after healing period were recorded. CONCLUSIONS: Three-dimensional ultrasound techniques seem to be the best tool for complex pre- and postoperative management of Robert's uterus. Minimally invasive ultrasound-guided hysteroscopic metroplasty should be considered as the first choice of treatment because of the potential for normalization of uterine morphology and function.