Resection Volume Research Articles

Rotitome-G: Principles and design concept of experimental compliant continuum robotic microsurgical endoscopic sarcotome for pixel/voxel-level target access neurosurgery

The practice of minimal access surgery is widely accepted, and it has become prevalent with improved endoscope design. The traditional microscope in neurosurgery is gradually being challenged by the neuro-endoscope for its direct co-axial vision and direct illumination of the deep set subcortical pathology. The conceptualized design of Rotitome-G is based on compliant continuum robotic system. The system is a biomimicry of muscular hydrostat anatomy of the elephant trunk, a plant tendril, and many similar structures in the animal world with an infinite degree of freedom. The article describes the functional anatomy of these structures and the extensor expansion of the human finger as applied to the construction and implementation of the Rotitome-G. This flexible microsurgical endoscope integral to its design has unique cutting tool versions and multiple assistive tools passed through single ‘target access’ burr hole aperture. It is navigable within the surgical space co-relative to the image space to increase precision and improve the volume of tumour resection. The current study is theoretical and further work is in progress to assess its surgical capabilities to bring it to the clinical arena.

CTNI-45. UPFRONT CHEMOTHERAPY AND SUBSEQUENT RESECTION UTILIZING NEOADJUVANT STRATEGY FOR OLIGODENDROGLIOMAS

Abstract Although both of functional preservation and higher extent of resection are required in glioma surgery, maximal resection with the risk of functional sequela is uniformly performed regardless of tumor pathology and treatment sensitivity in the current practice. Oligodendrogliomas are known to be associated with relatively favorable prognosis, however, many patients still eventually succumb to death due to tumors. Improvement in the long-term survival rate and functional preservation would be the next step to be achieved. In our hospital, patients with 1p/19q-codeleted glioma have been treated by upfront chemotherapy, if deemed in need of adjuvant treatment after initial resection, since 2006. If the initial resection was incomplete, the second surgery was intended following tumor volume decrease by chemotherapy (second-look resection, SLR). Intentional staged resection was performed in several cases for whom presence of 1p/19q codeletion was strongly suggested based on preoperative imaging characteristics. Utility of this strategy was evaluated. Forty-one patients with 1p/19q-codeleted glioma have been treated with the strategy. Of these, 30 were grade 2, and 11 were grade 3 tumors. In 9 of the 41 cases, radiotherapy was prescribed immediately after chemotherapy or SLR. Median tumor volume decrease rate by chemotherapy in the cases with initial incomplete resection was -35%. SLR following tumor volume decrease was performed in 22 cases. Median progression-free survival and overall survival after the initiation of chemotherapy were 81 months and 175 months for each in both of the total 41 cases and 32 cases for whom radiotherapy was deferred. Most of the recurrence occurred in the residual FLAIR high intensity. Upfront chemotherapy and subsequent resection strategy utilizing chemotherapeutic response provides more precise resection as well as reduction of resection volume as compared with one-time maximal safe resection. Radiotherapy may be indicated for the cases with residual FLAIR abnormality after chemotherapy or SLR.

Expanded indications for breast-conserving surgery with oncoplastic approaches compared to conventional approaches: a single-center retrospective comparative cohort study.

Oncoplastic breast-conserving surgery (OPBS) is the evolution of conventional breast-conserving surgery (CBCS); however, data from studies comparing patients who received two surgical procedures are limited. A comparison of differences in terms of the patient characteristics, tumor-nipple distance, volume of resected breast tissue, tumor volume and postoperative breast appearance between patients undergoing OPBS and CBCS was carried out in this study, enhancing the evidence base for OPBS by widening indications and improving patient satisfaction. From January 2020 to April 2022, the Breast Center of West China Hospital conducted a retrospective comparative study involving 106 patients. Preoperative characteristics of patients were recorded, and the tumor-nipple distance, the volume of resected breast tissue, tumor volume and patient-reported esthetic outcomes measured by the Harris cosmetic scale were compared between patients who underwent OPBS and CBCS. Each group had a median follow-up time of 2 months, ranging from 1 week to 6 months. The tumor-nipple distance was significantly shorter in patients receiving OPBS than in those receiving CBCS (2.98±1.42 vs. 3.85±1.78 cm, P=0.006). The rate of positive margin evaluated by intraoperative frozen section biopsy was significantly lower in OPBS group than in CBCS group (2/43, 4.65% vs. 11/63, 17.46%; P=0.048). The maximum diameter of resected tissue (7.80±2.29 vs. 6.75±1.87 cm, P=0.011) and volume of resected tissue (74.20±42.77 vs. 45.52±30.99 cm3, P<0.001) were significantly larger with OPBS. The tumor size, tumor volume (either clinically measured by ultrasound or pathologically measured), tumor location, and reoperation rate due to positive margins did not differ significantly between groups. Moreover, insignificant differences existed regarding patient satisfaction between two groups (87.30% vs. 81.40%). The OPBS strategy allowed extensive resections and expanded indications with equivalent cosmetic satisfaction and favorable oncological safety.

Numerical and experimental analysis of pollen inhalation exposure in nasal airways following various middle turbinectomy

BackgroundMiddle turbinectomy (MT) has always been controversial. MT significantly alters the anatomy and redistributes the inhaled air. The current study is designed to quantify the effect of MT with varying resection volumes on airflow and associated pollen inhalation exposure characteristics in the nasal airways. MethodsSix realistic models following bilateral comprehensive Functional Endoscopic Sinus Surgery (FESS) deriving from CT images were constructed and their corresponding post-MT models with four types of MT procedures were virtually conducted. Inhalation exposure to pollen particles was simulated by the Computational Fluid-Particle Dynamics (CFPD) approach and validated through in vitro experiments. ResultsFollowing the excision of the middle turbinate, a significant escalation in airflow was observed within the upper-middle region of the nasal cavities. Pollen deposition was observed to be more prominent in the nasal septum, laryngopharynx, and maxillary sinus, varying with the types of MT procedures. Notably, particles with diameters smaller than 50 μm exhibited two distinct “high peaks” and three “small peaks” within the nasal airways. ConclusionMT resulted in increased airflow volume within the upper-middle region of the nasal cavities. Following MT, notable shifts in pollen particle deposition hot spots were observed, transitioning from the nasal vestibule, nasal septum, and middle meatus to the nasal septum and laryngopharynx. These findings are anticipated to contribute valuable perspectives on pollen inhalation exposure risk assessments following diverse MT surgical interventions.

Predictors of acute kidney injury after lung resection surgery: a retrospective case-control study.

Patients undergoing lung resection are at increased risk for acute kidney injury (AKI) in the immediate postoperative period, with important consequences for longer term morbidity and mortality. Lung resection surgery has unique considerations that could increase the risk of AKI, including lung resection volume, duration of one-lung ventilation (OLV), and intraoperative fluid restriction. Yet, specific risk factor data are lacking. The objective of this study was to identify independent risk factors for early AKI after lung resection surgery. We conducted a retrospective case-control study of all patients presenting for elective lung resection surgery at an academic medical centre over a four-year period. Cases were patients who experienced an AKI and control patients were those who did not experience an AKI, based on KDIGO criteria. Baseline demographics and comorbidities along with duration of OLV and amount of lung resected were collected by retrospective chart review. The data were analyzed using multivariable logistic regression to identify independent predictors of AKI. Acute kidney injury occurred within 48hr in 57/1,045 (5.5%; 95% confidence interval, 4.2 to 7.0) of patients. On multivariable analysis, our model of best fit included preoperative serum creatinine, male sex, use of angiotensin II receptor blockers, and duration of OLV. The rate of complications, intensive care unit admission, and risk of death were all higher in the group of patients who experienced AKI. Acute kidney injury occurs frequently after lung resection surgery and is associated with increased risk of postoperative complications. Increased duration of OLV may be a risk factor for AKI in this population.

The use of a linear versus curvilinear oscillating saw blade for femoral head and neck excision surgery in cats.

To determine the effects of using either a linear or curvilinear oscillating, battery-powered saw blade on the extent of bone resection, bone fissure or fragmentation, soft tissue trauma, and surgical time for femoral head and neck excision (FHNE) in feline cadavers. 18 feline cadavers. Paired feline cadaveric femora were randomly assigned to either a 10 mm linear or 12 mm curvilinear blade for FHNE by 2 surgical residents. CT of each femur pre- and postoperatively were used to create 3D reconstructions of each femur. The residual remaining or excessively resected bone volume at the ostectomy site was compared to an "ideal" ostectomy line made by a board-certified surgeon on preoperative CTs. There were no significant differences in residual or excessive bone resection by a saw blade (P = .84), between surgeons (P = .65), or in surgery time (P = .39). When compared to the "ideal" ostectomy, the linear saw blade removed slightly less bone compared to the curvilinear blade, but was not statistically significant (P = .82). No fissures or fractures were noted; however, the curvilinear blade removed the entire lesser trochanter in 1 cadaver and the linear blade partially removed the greater trochanter in 1 femur and 2 lesser trochanters in 2 femora. The use of a curvilinear blade may be a viable option for performing FHNE in cats. In vivo studies are warranted to determine its efficacy in clinical cases where FHNE is performed and the incidence of complications postoperatively.

Interpretable machine learning accurately reclassifies lobectomy surgical approaches by cost

BackgroundThe volume of robotic lung resection continues to increase despite its higher costs and unproven superiority to video-assisted thoracoscopic surgery. We evaluated whether machine learning can accurately identify factors influencing cost and reclassify high-cost operative approaches into lower-cost alternatives. MethodsThe Florida Agency for Healthcare Administration and Centers for Medicare and Medicaid Services Hospital and Physician Compare datasets were queried for patients undergoing open, video-assisted thoracoscopic surgery and robotic lobectomy. K-means cluster analysis was used to identify robotic clusters based on total cost. Predictive models were built using artificial neural networks, Support Vector Machines, Classification and Regression Trees, and Gradient Boosted Machines algorithms. Models were applied to the high-volume robotic group to determine patients whose cost cluster changed if undergoing a video-assisted thoracoscopic surgery approach. A local interpretable model-agnostic explanation approach personalized cost per patient. ResultsOf the 6,618 cases included in the analysis, we identified 4 cost clusters. Application of artificial neural networks to the robotic subgroup identified 1,642 (65%) cases with no re-assignment of cost cluster, 583 (23%) with reduced costs, and 300 (12%) with increased costs if they had undergone video-assisted thoracoscopic surgery approach. The 5 overall highest cost predictors were patient admission from the clinic, diagnosis of metastatic cancer, presence of cancer, urgent hospital admission, and dementia. ConclusionK-means cluster analysis and machine learning identify a patient population that may undergo video-assisted thoracoscopic surgery or robotic lobectomy without a significant difference in total cost. Local interpretable model-agnostic explanation identifies individual patient factors contributing to cost. Application of this modeling may reliably stratify high-cost patients into lower-cost approaches and provide a rationale for reducing expenditure.

Persistent racial disparities in refusal of resection in non-small cell lung cancer patients at high-volume and Black-serving institutions

BackgroundSurgical resection is the standard of care for early-stage non-small cell lung cancer. Black patients have higher surgical refusal rates than White patients. We evaluated factors associated with the refusal of resection and subsequent non-small cell lung cancer outcomes. MethodsWe identified patients with non-small cell lung cancer stages IA to IIIA eligible for surgical resection (lobectomy or pneumonectomy) listed between 2004 and 2017 in the National Cancer Database. We stratified hospitals by the proportion of Black patients served and lung cancer resection volume. We used multivariable regression models to identify factors associated with refusal of resection and assessed 5-year mortality using Kaplan–Meier analysis and Cox proportional hazard modeling. ResultsOf 221,396 patients identified, 7,753 (3.5%) refused surgery. Black race was associated with increased refusal (adjusted odds ratio 2.06, 95% confidence interval 1.90–2.22). Compared to White race, Black race was associated with increased refusal across the highest (adjusted odds ratio 2.29, 95% confidence interval 1.94–2.54), intermediate (adjusted odds ratio 2.05, 95% confidence interval 1.78–2.37), and lowest (adjusted odds ratio 1.77, 95% confidence interval 1.58–1.99) volume tertiles. Similarly, Black race was associated with increased refusal across the highest (adjusted odds ratio 1.97, 95% confidence interval 1.78–2.17), intermediate (adjusted odds ratio 2.08, 95% confidence interval 1.80–2.40), and lowest (adjusted odds ratio 1.53, 95% confidence interval 1.13–2.06) Black-serving tertiles. However, surgical resection yielded similar 5-year survival for Black and White patients. ConclusionRacial disparities in non-small cell lung cancer surgery refusal persist regardless of hospital volume or proportion of Black patients served. These findings suggest that a better understanding of patient and patient–provider level interventions could facilitate a better understanding of treatment decision-making.

H - 39 Clinical Utility of the Rey-Osterrieth Complex Figure Test (RCFT) and Neuropsi a & M Semi-Complex Figure in Spanish Language Neuropsychological Evaluations.

The Rey-Osterrieth Complex Figure Test (RCFT) is a widely administered neuropsychological instrument. The clinical utility of using the RCFT to assist with interpretation of cognitive profiles has been well-documented; however, the utility of Spanish-language administrations is less well-known. One common adaptation for patients with lower educational attainment is the use of a simpler, semi-complex figure. These adaptations are notable for differences in administration (i.e., copy and delay with no immediate trial) and more lenient scoring criteria. This qualitative case series comparison samples both the construction of the RCFT and semi-complex figure in three adult patients with lower education. All administrations of the RCFT and semi-complex figure were given in Spanish as part of a larger comprehensive neuropsychological battery. One example is a 56-year-old, monolingual, Spanish-speaking man with six years of education. He presented with a history of right frontal glioblastoma resection and diffuse cerebral volume loss and hyperintensities; alcohol use, and poor adherence to antiseizure medications. His performance on the RCFT was well below expectations in the less than 1st percentile. Qualitative analysis of his construction revealed a piecemeal approach with poor approximation to the gestalt. Overall, his construction implicated non-dominant hemisphere and was consistent with other neurodiagnostic and neuropsychological data. Research to replicate the clinical utility of the RCFT and semi-complex figure in Spanish-language administrations is helpful for improving diagnostic sensitivity in minority patient populations. Through case examples, this case series illustrates the clinical utility of the RCFT and semi-complex figure as comparable across languages (i.e., English versus Spanish-language administrations).

Surgical treatment using a laser with a wavelength of 445 nm in patients with chronic paralytic laryngeal stenosis

The treatment of chronic paralytic laryngeal stenosis remains a relevant issue. It ranks second and accounts for 29.9% of chronic diseases of the laryngeal plexus. The number of affected patients has increased 10-fold over the past 10 years (20102020). Surgical treatment of chronic paralytic laryngeal stenosis is aimed at respiratory function restoration and the possibility of decanulation of the patient while maintaining vocal function. In the literature, the effectiveness of surgical treatment of patients with laryngeal stenosis varies greatly, ranging from 22% to 94%. We have proposed a technique for performing laryngoplasty in a patient with chronic paralytic laryngeal stenosis using a laser with a wavelength of 445 nm with a supply of inert gas (helium) in the operating field. When helium was injected into the operating field, the oxygen content at the laser exposure site decreased; thus, the effect of tissue carbonation was minimized, and thermal damage to surrounding tissues was reduced. Owing to the presence of gas, the smoke generated during the operation was quickly removed from the operating field, which provided good visualization. The properties of the aforementioned laser ensure a bloodless operating field, increasing the accuracy of surgical intervention. When using this laser, thermal damage to the surrounding tissues is no more than 0.6 cm in depth. This minimizes inflammatory reactions in the larynx in the postoperative period and promotes faster patient rehabilitation. The proposed volume of resection of the anatomical structures of the larynx was as follows: the posterior two-thirds of the vocal muscle and the anterior two-thirds of the body of the arytenoid cartilage, with the preservation of the mucous membrane to close the surgical wound, which ensures healing by primary tension and creates the necessary lumen of the glottis for sufficient breathing and allows for the maintenance acceptable voice function for patient communication. A laser with a 445-nm wavelength and a flap for closing the surgical wound used during the operation can speed up the recovery process and reduce the risk of relapse. This technique can be a method of choice for the treatment of patients with paralytic laryngeal stenosis.

Effects of resection volume on postoperative micturition symptoms and retreatment after transurethral resection of the prostate

PurposeDespite advances in technology, such as advent of laser enucleation and minimally invasive surgical therapies, transurethral resection of the prostate (TURP) remains the most widely performed surgical technique for benign prostatic hyperplasia (BPH). We evaluated resection volume (RV)-derived parameters and analyzed the effect of RV on post-TURP outcomes.MethodsThis observational study used data from patients who underwent TURP at two institutions between January 2011 and December 2021 Data from patients with previous BPH surgical treatment, incomplete data, and underlying disease affecting voiding function were excluded. The collected data included age, prostate-specific antigen, transrectal ultrasound (TRUS)- and uroflowmetry-derived parameters, RV, perioperative laboratory values, perioperative International Prostatic Symptom Score (IPSS), follow-up period, retreatment requirements and interval between the first TURP and retreatment.ResultsIn 268 patients without prior BPH medication, there were no differences in prostate volume (PV), transitional zone volume (TZV), or RV according to IPSS. A total of 60 patients started retreatment, including medical or surgical treatment, within the follow-up period. There was a significant difference in RV/PV between the groups without and with retreatment respectively (0.56 and 0.37; p = 0.008). However, preoperative TRUS- and uroflowmetry-derived parameters did not differ between the two groups. Multiple linear regression analysis showed that RV (p = 0.003) and RV/TZV (p = 0.006) were significantly associated with differences in perioperative IPSS. In the multivariate logistic regression analysis, only RV/PV was correlated with retreatment (p = 0.010).ConclusionMaximal TURP leads to improved postoperative outcomes and reduced retreatment rate, it may gradually become a requirement rather than an option.

Weight to volume conversion: an easy and practical breast volume estimation.

Accurate breast volume estimation is essential for symmetrical breast reconstruction. Easy conversion of the weight of the resected breast tissue to volume could result in precise volume measurements. This study aimed to introduce the use of a mathematical constant (k) to estimate the breast volume from the weight. Eighty-nine female patients with breast cancer who underwent surgery at King Chulalongkorn Memorial Hospital between September 2010 and February 2011 were enrolled in this prospective study. The mammographic density of each patient was classified according to the breast imaging reporting and data system (BI-RADS) into groups a, b, c, and d. The breast density number and mathematical constant (k) were calculated, and the data matched. This technique was validated by comparing the measured and calculated volumes. Sixty-six, 22, and 1 patients underwent total mastectomies (TMs), skin-sparing mastectomies (SSMs), and nipple-sparing mastectomies (NSMs), respectively. The breast densities were 1.0629, 1.1545, and 1.2233 g/mL, and the constant number (k) was 0.9409, 0.8662, and 0.8175 for BI-RADS a, combined BI-RADS b and c, and BI-RADS d, respectively. The validation process showed no significant differences between the measured and calculated volumes [95% confidence interval (95% CI)]. The correlation coefficient (r) was 0.984. Accurate breast volume estimation is a key factor in achieving symmetry in breast reconstruction. Combining existing data, including the weight of the resected breast tissue and mammographic density findings, an easy and accurate method to calculate the resected breast volume was introduced.

Application of augmented reality navigation combined with indocyanine green fluorescence imaging technology in the accurate guidance of laparoscopic anatomical segment 8 liver resection

Objective: To investigate the application value of augmented reality navigation combined with indocyanine green(ICG) fluorescence imaging technology in laparoscopic anatomical segment 8 liver resection. Methods: Clinical and pathological data from 8 patients with hepatocellular carcinoma located in segment 8 of the liver admitted to the First Department of Hepatobiliary Surgery,Zhujiang Hospital,Southern Medical University from October 2021 to October 2022 were collected restrospectively. Among them,there were 5 males and 3 females,aged between 40 and 72 years. During the operation,the self-developed laparoscopic augmented reality surgical navigation system was used to integrate the three-dimensional liver model with the laparoscopic scene,and ICG fluorescence imaging technology was used to guide the anatomical liver resection of segment 8. The predicted liver resection volume and actual liver resection volume,related surgical indicators and postoperative complications were analyzed. Results: Among the 8 patients, 4 underwent laparoscopic anatomical segment 8 liver resection,1 underwent laparoscopic anatomical ventral subsegment of segment 8 liver resection,2 underwent laparoscopic anatomical ventral subsegment combined with medial subsegment of segment 8 liver resection, and 1 underwent laparoscopic anatomical dorsal subsegment of segment 8 liver resection. All operations were completed under the guidance of augmented reality navigation combined with ICG fluorescence imaging,without conversion to open surgery. The operation time was (276.3±54.8)minutes(range:200 to 360 minutes). Intraoperative blood loss was (75.0±35.4)ml(range:50 to 150 ml). No blood transfusion was performed during the operation. The length of postoperative hospital stay was (7.6±0.8)days(range:7 to 9 days). There were no deaths or postoperative complications such as bleeding or biliary fistula during the perioperative period. Conclusion: Augmented reality navigation combined with ICG fluorescence imaging technology can guide the implementation of laparoscopic anatomical segment 8 liver resection.

Automated volumetric assessment of pituitary adenoma

PurposeAssessment of pituitary adenoma (PA) volume and extent of resection (EOR) through manual segmentation is time-consuming and likely suffers from poor interrater agreement, especially postoperatively. Automated tumor segmentation and volumetry by use of deep learning techniques may provide more objective and quick volumetry.MethodsWe developed an automated volumetry pipeline for pituitary adenoma. Preoperative and three-month postoperative T1-weighted, contrast-enhanced magnetic resonance imaging (MRI) with manual segmentations were used for model training. After adequate preprocessing, an ensemble of convolutional neural networks (CNNs) was trained and validated for preoperative and postoperative automated segmentation of tumor tissue. Generalization was evaluated on a separate holdout set.ResultsIn total, 193 image sets were used for training and 20 were held out for validation. At validation using the holdout set, our models (preoperative / postoperative) demonstrated a median Dice score of 0.71 (0.27) / 0 (0), a mean Jaccard score of 0.53 ± 0.21/0.030 ± 0.085 and a mean 95th percentile Hausdorff distance of 3.89 ± 1.96./12.199 ± 6.684. Pearson’s correlation coefficient for volume correlation was 0.85 / 0.22 and −0.14 for extent of resection. Gross total resection was detected with a sensitivity of 66.67% and specificity of 36.36%.ConclusionsOur volumetry pipeline demonstrated its ability to accurately segment pituitary adenomas. This is highly valuable for lesion detection and evaluation of progression of pituitary incidentalomas. Postoperatively, however, objective and precise detection of residual tumor remains less successful. Larger datasets, more diverse data, and more elaborate modeling could potentially improve performance.

Oncoplastic breast conserving surgery versus standard breast conserving surgery for early and locally advanced breast cancer: a retrospective analysis from Sri Lanka

BackgroundBreast aesthetics is becoming increasingly important in breast cancer surgery due to changes in patient expectations and greater emphasis been placed on the psychosocial outcomes. Studies have shown no difference in local recurrence risk between mastectomy and breast conserving surgery (BCS) and also a higher overall survival rate after BCS. Breast preservation improves the quality of life substantially compared to mastectomy. Oncoplastic breast-conserving surgery (O-BCS) involves tumour excision whilst overcoming the limitations of standard breast conserving surgery (S-BCS) by allowing larger resection volumes, avoiding deformities with better aesthetic results. Our study aims to compare the oncosurgical and aesthetic outcomes of O-BCS versus S-BCS among women in Sri Lanka.MethodsWe conducted a retrospective study over a 4-year period including patients who underwent breast conservation surgery for primary non-metastatic breast cancer in two tertiary care units. We assessed outcomes in terms of re-excision rates, resection margin, complications and aesthetic outcomes using a Likert scale questionnaire to grade specific outcomes such as symmetry, volume, nipple position, scar visibility. Non-parametric tests were used for statistical analyses.ResultsFifty-four and seventy-three patients underwent S-BCS and O-BCS respectively. The median specimen volume and the maximum tumour diameter were significantly higher in O-BCS [160(range:65–220); 4.2(range: 1.2–5.2)] compared to S-BCS [65(range:45–86); 2.4(range: 1.0-2.6)]. The median closest tumour margin was 16 mm (range:4-25 mm) in O-BCS while 6 mm (range:<1 – 12 mm) in S-BCS (p = 0.01). Close (< 1 mm) and positive margins needing re-excision were seen mostly in S-BCS. Superior aesthetic outcomes with statistical significant difference were reported in the O-BCS compared to S-BCS group with better symmetry, volume, nipple position and scar visibility. The re-excision rates were significantly lower in O-BCS group. There was no significant difference in the operative time and complications while the aesthetic outcomes were significantly superior in OBCS.ConclusionsOverall, Level 2 perforator flap based reconstruction had superior aesthetic outcomes. O-BCS is safe and more aesthetically acceptable with no difference in oncological outcome and operative time. More consideration should be given to aesthetic parameters such as scar visibility, nipple position, breast volume and shape when considering the best surgical option for the patients.

P11.11.A VOLUMETRIC AND SPATIAL ANALYSES OF TREATMENT-RELATED INJURY IN GLIOMA

Abstract BACKGROUND As diffuse glioma cannot yet be cured, benefits of therapeutic strategies should be carefully balanced against their burden. Postoperative ischemia is a relatively common adverse event of surgery, which can lead to serious neurological deficits. Radiation therapy (RT) can cause post-RT lesions, which may cause clinical symptoms and can create a therapeutic impasse since they mimic tumor progression. We aimed to explore the spatial and volumetric tumor and treatment characteristics in relation to development of treatment-related effects in glioma. Materials and METHODS We retrospectively included 144 WHO grade II-IV supratentorial glioma cases, which were resected from 2012 till 2014 and had early postoperative MRI with diffusion-weighted imaging (DWI). Tumors were delineated on preoperative contrast-enhanced T1 MRI for high grade gliomas and FLAIR for low grade gliomas. Postoperative ischemia was defined as new, confluent diffusion restriction on postoperative DWI. Post-RT injury was investigated in patients who received RT after first surgery and had at least 6 months of follow-up (FU), and was defined as new or increasing contrast-enhancement that subsequently stabilized or decreased during FU. After manual delineation and non-linear registration to MNI stereotaxic space, all lesions were investigated with regard to size and location of pre-operative tumor, resection cavity, residual tumor and extent of resection (EOR). Voxel-based analysis (VBA) was performed with family-wise error correction for multiple comparisons. RESULTS Postoperative ischemia occurred in 93 of 144 cases and was associated with a larger EOR (P=0.02). Ischemic volume was correlated with a larger preoperative tumor volume (P=0.009) and resection volume (P=0.001). Post-RT injury was found in 25 of 67 analyzed cases and was associated with a larger residual tumor volume (P=0.021) and a smaller EOR (P=0.005). VBA showed an association of the occurrence of post-RT lesions with a cluster of preoperative tumor voxels in the left temporal lobe and clusters of residual tumor voxels in the left temporal and right frontal region. No association in volume or location was found between postoperative ischemia and post-RT lesions. CONCLUSION Adverse events of glioma treatment may be influenced by tumor and treatment volumes. In our population, a larger EOR was associated with the occurrence of postoperative ischemia, and larger tumor and resection volumes were correlated with the volume of ischemia. Additionally, the occurrence of post-RT injury was associated with a larger residual tumor and a smaller EOR, as well as a left temporal preoperative tumor location and a right frontal or left temporal residual tumor location. A thorough examination of spatial and volumetric characteristics of the tumor, treatment and subsequent complications can help elucidate the etiology and guide treatment decisions.

International survey on opinions and use of robot-assisted and laparoscopic minimally invasive pancreatic surgery: 5-year follow up

BackgroundEvidence on the value of minimally invasive pancreatic surgery (MIPS) has been increasing but it is unclear how this has influenced the view of pancreatic surgeons on MIPS. MethodsAn anonymous survey was sent to members of eight international Hepato-Pancreato-Biliary Associations. Outcomes were compared with the 2016 international survey. ResultsOverall, 315 surgeons from 47 countries participated. The median volume of pancreatic resections per center was 70 (IQR 40–120). Most surgeons considered minimally invasive distal pancreatectomy (MIDP) superior to open (ODP) (94.6%) and open pancreatoduodenectomy (OPD) superior to minimally invasive (MIPD) (67.9%). Since 2016, there has been an increase in the number of surgeons performing both MIDP (79%–85.7%, p = 0.024) and MIPD (29%–45.7%, p < 0.001), and an increase in the use of the robot-assisted approach for both MIDP (16%–45.6%, p < 0.001) and MIPD (23%–47.9%, p < 0.001). The use of laparoscopy remained stable for MIDP (91% vs. 88.1%, p = 0.245) and decreased for MIPD (51%–36.8%, p = 0.024). ConclusionThis survey showed considerable changes of MIPS since 2016 with most surgeons considering MIDP superior to ODP and an increased use of robot-assisted MIPS. Surgeons prefer OPD and therefore the value of MIPD remains to be determined in randomized trials.

Comparison of ultrasound guided surgery and radio-guided occult lesions localization (ROLL) for nonpalpable breast cancer excision.

There is little literature comparing intraoperative ultrasound (IOUS) with radio-guided occult lesions localization (ROLL) in nonpalpable invasive tumors in breast conserving surgery (BCS). There is a need to compare these two methods in terms of safety and efficacy. This is an observational cohort study. All patients treated with BCS for nonpalpable invasive breast cancer using IOUS from March 2016 to March 2020 were included and compared with a historical reference control group operated on using ROLL from March 2013 to March 2017. For each detection method, the ability to locate tumors intraoperatively, tumor and surgical specimen sizes, total resection volume (TRV), optimal resection volume, excess of healthy tissue resected (ETR), margin status, re-excision rate, surgical time, complications and costs were studied. One hundred and fifty-eight were included, 83 with IOUS and 75 with ROLL. The mean tumor size is equivalent in both groups (11.88 mm IOUS vs. 12.29 mm ROLL, P=0.668). TRV is significantly lower with IOUS (24.92 vs. 60.32 cm3, P<0.001), and the ETR is also significantly lower in the IOUS group (21.74 vs. 58.37 cm3, P<0.001). The rate of positive margins did not differ (10.98% vs. 12.16%, P=1), nor did re-excision rate (10.98% vs. 8.11%, P=0.597). Complication rate did not differ (12.2% IOUS vs. 10.81% ROLL, P=0.808). Surgical time was shorter in IOUS (45.5 vs. 57 min, P>0.05). IOUS in BCS for nonpalpable invasive breast cancer is more accurate than ROLL because it decreases excision volumes with the same rate of free margins and re-excision. Also, IOUS is a more efficient and comfortable technique, and just as safe as ROLL.

Volumetric extent of resection and survival for recurrent atypical meningioma.

In recurrent atypical meningioma, the survival impact of volumetric extent of resection (vEOR) and residual tumor volume (RTV) has not been previously studied. The authors performed a retrospective vEOR analysis of patients with recurrent World Health Organization grade II meningiomas treated with reresection from 2000 to 2019. The Kaplan-Meier method and multivariate Cox regression analysis were used to study progression-free survival (PFS) and overall survival (OS). Fifty-nine patients with a median follow-up duration of 95 (95% CI 42-148) months were included. The median (range) vEOR was 100% (32%-100%) and the mean ± SD was 90.7% ± 15.3%. Among patients who underwent gross-total resection (GTR) (n = 32 [54%]), Simpson grade I and II resections were achieved in 23 (72%) and 9 (28%) patients, respectively. Among patients who underwent subtotal resection (n = 27 [46%]), the median (range) RTV was 4.3 (0.3-40) cm3. The 1-, 2-, and 5-year actuarial PFS rates for the cohort were 76%, 56%, and 34%, respectively. The 1-, 2-, and 5-year actuarial OS rates for the cohort were 98%, 78%, and 60%, respectively. Variables reflecting EOR significantly impacted both PFS and OS in multivariate analysis: GTR (p < 0.01) was significantly associated with longer PFS, and lower Simpson grade (p = 0.04) was significantly associated with longer OS. Additional factors including RTV, Ki-67 index, and pretreatment and posttreatment history also impacted survival outcomes (p < 0.05). EOR and Simpson grade were independently associated with survival outcomes in patients with recurrent atypical meningioma. These findings support the practice of thorough reresection for maximal cytoreduction in appropriate surgical candidates.

Accurate resection of hilar cholangiocarcinoma using eOrganmap 3D reconstruction and full quantization technique.

For treatment of hilar cholangiocarcinoma (HCCA), the rate of radical resection is low and prognosis is poor, and preoperative evaluation is not sufficiently accurate. 3D visualization has the advantage of giving a stereoscopic view, which makes accurate resection of HCCA possible. To establish precise resection of HCCA based on eOrganmap 3D reconstruction and full quantification technology. We retrospectively analyzed the clinical data of 73 patients who underwent HCCA surgery. All patients were assigned to two groups. The traditional group received traditional 2D imaging planning before surgery (n = 35). The eOrganmap group underwent 3D reconstruction and full quantitative technical planning before surgery (n = 38). The preoperative evaluation, anatomical classification of hilar hepatic vessels, indicators associated with surgery, postoperative complications, liver function, and stress response indexes were compared between the groups. Compared with the traditional group, the amount of intraoperative blood loss in the eOrganmap group was lower, the operating time and postoperative intestinal ventilation time were shorter, and R0 resection rate and lymph node dissection number were higher (P < 0.05). The total complication rate in the eOrganmap group was 21.05% compared with 25.71% in the traditional group (P > 0.05). The levels of total bilirubin, Albumin (ALB) , aspartate transaminase, and alanine transaminase in the eOrganmap group were significantly different from those in the traditional group (intergroup effect: F = 450.400, 79.120, 95.730, and 13.240, respectively; all P < 0.001). Total bilirubin, aspartate transaminase, and alanine transaminase in both groups showed a decreasing trend with time (time effect: F = 30.270, 17.340, and 13.380, respectively; all P < 0.001). There was an interaction between patient group and time (interaction effect: F = 3.072, 2.965, and 2.703, respectively; P = 0.0282, 0.032, and 0.046, respectively); ALB levels in both groups tended to increase with time (time effect: F = 22.490, P < 0.001), and there was an interaction effect between groups and time (interaction effect: F = 4.607, P = 0.004). In the eOrganmap group, there was a high correlation between the actual volume of intraoperative liver specimen resection and the volume of preoperative virtual liver resection (t = 0.916, P < 0.001). The establishment of accurate laparoscopic resection of hilar cholangiocarcinoma based on preoperative eOrganmap 3D reconstruction and full quantization technology can make laparoscopic resection of hilar cholangiocarcinoma more accurate and safe.