Application of Three-Dimensional Visualization Technology in Laparoscopic Partial Nephrectomy of Renal Tumor: A Comparative Study

Are 3D Image Guidance Systems Ready for Use? A Comparative Analysis of 3D Image Guidance Implementations in Minimally Invasive Partial Nephrectomy

Introduction: Three-dimensional image-guided surgical (3D-IGS) systems for minimally invasive partial nephrectomy (MIPN) can potentially improve the efficiency and accuracy of intraoperative anatomical localization and tumor resection. This review seeks to analyze the current state of research regarding 3D-IGS, including the evaluation of clinical outcomes, system functionality, and qualitative insights regarding 3D-IGS's impact on surgical procedures. Methods: We have systematically reviewed the clinical literature pertaining to 3D-IGS deployed for MIPN. For inclusion, studies must produce a patient-specific 3D anatomical model from two-dimensional imaging. Data extracted from the studies include clinical results, registration (alignment of the 3D model to the surgical scene) method used, limitations, and data types reported. A subset of studies was qualitatively analyzed through an inductive coding approach to identify major themes and subthemes across the studies. Results: Twenty-five studies were included in the review. Eight (32%) studies reported clinical results that point to 3D-IGS improving multiple surgical outcomes. Manual registration was the most utilized (48%). Soft tissue deformation was the most cited limitation among the included studies. Many studies reported qualitative statements regarding surgeon accuracy improvement, but quantitative surgeon accuracy data were not reported. During the qualitative analysis, six major themes emerged across the nine applicable studies. They are as follows: 3D-IGS is necessary, 3D-IGS improved surgical outcomes, researcher/surgeon confidence in 3D-IGS system, enhanced surgeon ability/accuracy, anatomical explanation for qualitative assessment, and claims without data or reference to support. Conclusions: Currently, clinical outcomes are the main source of quantitative data available to point to 3D-IGS's efficacy. However, the literature qualitatively suggests the benefit of accurate 3D-IGS for robotic partial nephrectomy.

Holographic 3D renal segments reconstruction protects renal function by promote choice of selective renal artery clamping during robot-assisted partial nephrectomy

OBJECTIVE

To investigate the impact of selective artery clamping (SAC) and main artery clamping (MAC) during robot-assisted partial nephrectomy (RAPN) on renal function and the influence of holographic three-dimensional (3D) reconstruction of renal segments on the selection between SAC and MAC.

METHODS

This retrospective observational study included patients who underwent RAPN at First Hospital Affiliated to the Army Medical University between December 2016 and July 2022. According to the clamping methods, the patients were divided into the SAC group and the MAC group. The primary outcome was renal function.

RESULTS

A total of 422 patients (194 in the SAC group and 228 in the MAC group) were included. The RAPN procedures were all completed successfully. The patients in SAC group had less glomerular filtration rate (GFR) decline in the affected kidney (8.6 ± 7.0 ml/min vs. 18.7 ± 10.9 ml/min, P < 0.001) and minor estimated glomerular filtration rate (eGFR) decrease (4.3 ± 10.5 ml/min vs. 12.6 ± 12.1 ml/min, P < 0.001) than those in MAC group. Among 37 patients with baseline renal insufficiency, the GFR decline of the affected kidney in the SAC subgroup was significantly lower than in the MAC subgroup (5.5 ± 6.5 ml/min vs. 14.3 ± 9.2 ml/min, P = 0.002). The proportion of patients who underwent 3D reconstruction was significant higher in the SAC group than in the MAC group. (65.46% vs. 28.07%, P < 0.001).

CONCLUSION

The SAC technique during RAPN may serve as a protective measure for renal function, while the implementation of holographic 3D renal segment reconstruction technique may facilitate optimal selection of SAC.

Three-Dimensional Customized Imaging Reconstruction for Urological Surgery: Diffusion and Role in Real-Life Practice from an International Survey

Despite the arising interest in three-dimensional (3D) reconstruction models from 2D imaging, their diffusion and perception among urologists have been scarcely explored. The aim of the study is to report the results of an international survey investigating the use of such tools among urologists of different backgrounds and origins. Beyond demographics, the survey explored the degree to which 3D models are perceived to improve surgical outcomes, the procedures mostly making use of them, the settings in which those tools are mostly applied, the surgical steps benefiting from 3D reconstructions and future perspectives of improvement. One hundred responders fully completed the survey. All levels of expertise were allowed; more than half (53%) were first surgeons, and 59% had already completed their training. Their main application was partial nephrectomy (85%), followed by radical nephrectomy and radical prostatectomy. Three-dimensional models are mostly used for preoperative planning (75%), intraoperative consultation and tailoring. More than half recognized that 3D models may highly improve surgical outcomes. Despite their recognized usefulness, 77% of responders use 3D models in less than 25% of their major operations due to costs or the extra time taken to perform the reconstruction. Technical improvements and a higher availability of the 3D models will further increase their role in surgical and clinical daily practice.

A Safe Framework for Quantitative In Vivo Human Evaluation of Image Guidance

Goal: We present a new framework for in vivo image guidance evaluation and provide a case study on robotic partial nephrectomy. Methods: This framework (called the "bystander protocol") involves two surgeons, one who solely performs the therapeutic process without image guidance, and another who solely periodically collects data to evaluate image guidance. This isolates the evaluation from the therapy, so that in-development image guidance systems can be tested without risk of negatively impacting the standard of care. We provide a case study applying this protocol in clinical cases during robotic partial nephrectomy surgery. Results: The bystander protocol was performed successfully in 6 patient cases. We find average lesion centroid localization error with our IGS system to be 6.5 mm in vivo compared to our prior result of 3.0 mm in phantoms. Conclusions: The bystander protocol is a safe, effective method for testing in-development image guidance systems in human subjects.

CT Three-Dimensional Visualization Model in Diagnosis and Treatment of Stress Urinary Incontinence: A Retrospective Study

OBJECTIVE

To study the clinical effect of stress urinary incontinence sling surgery based on CT 3-dimensional visualization model, and to explore the value of three-dimensional visualization model in the diagnosis and treatment of stress urinary incontinence.

METHODS

Patients with stress urinary incontinence in our center from October 2020 to March 2022 were studied retrospectively. Among them, 16 cases received preoperative 3-dimensional visualization model construction, 18 cases did not use preoperative 3-dimensional model construction. The perioperative results, the postoperative results and the correlation between some related parameters of 3-dimensional visualization model and the severity of stress urinary incontinence were analyzed.

RESULTS

Compared with traditional surgery, the operation time of 3D group is significantly shorter (P < 0.05). There was no significant difference in intraoperative blood loss, perioperative fever, bleeding, micturition, pudendal or inguinal pain and postoperative symptom improvement. The posterior vesicourethral angle measured by 3-dimensional reconstruction model was correlated with ICI-Q-SF score.

CONCLUSIONS

The construction of three-dimensional visualization model of stress urinary incontinence can be used in clinic as a safe and effective new preoperative evaluation technique, and more potential applications can be further explored.

Three-dimensional Model-assisted Minimally Invasive Partial Nephrectomy: A Systematic Review with Meta-analysis of Comparative Studies

CONTEXT

Use of three-dimensional (3D) guidance for nephron-sparing surgery (NSS) has increased in popularity, especially for laparoscopic and robotic approaches. Different 3D visualization modalities have been developed as promising new tools for surgical planning and intraoperative navigation.

OBJECTIVES

To summarize and evaluate the impact of 3D models on minimally invasive NSS in terms of perioperative, functional, and oncological outcomes.

EVIDENCE ACQUISITION

A systematic literature search was conducted in December 2021 using the Medline (PubMed), Embase (Ovid), Scopus, and Web of Science databases. The protocol was registered on PROSPERO (CRD42022300948). The search strategy used the PICOS (Population, Intervention, Comparison, Outcome, Study design) criteria and article selection was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The risk of bias and the quality of the articles included were assessed. A dedicated data extraction form was used to collect the data of interest. Meta-analysis was performed using the Mantel-Haenszel method for binary outcomes, with results summarized as the odds ratio (OR), and the inverse variance method for continuous data, with results reported as the mean difference (MD). All effect estimates are reported with the 95% confidence interval (CI) and p ≤ 0.05 was considered statistically significant. All analyses were performed using R software and the meta package.

EVIDENCE SYNTHESIS

The initial electronic search identified 450 papers, of which 17 met the inclusion criteria and were included in the analysis. Use of 3D technology led to a significant reduction in the global ischemia rate (OR 0.22, 95% CI 0.07-0.76; p = 0.02) and facilitated more frequent enucleation (OR 2.54, 95% CI 1.36-4.74; p < 0.01) and less frequent opening of the collecting system (OR 0.36, 95% CI 0.15-0.89; p = 0.03) and was associated with less blood loss (MD 23.1 ml, 95% CI 31.8-14.4; p < 0.01). 3D guidance for NSS was associated with a significant reduction in the transfusion rate (OR 0.20, 95% CI 0.07-0.56; p < 0.01). There were no significant differences in rates of conversion to radical nephrectomy, minor and major complications, change in glomerular filtration rate, or surgical margins (all p > 0.05).

CONCLUSIONS

3D guidance for NSS is associated with lower rates of detriment and surgical injury to the kidney. Specifically, a lower amount of nontumor renal parenchyma is exposed to ischemia or sacrificed during resection, and opening of the collecting system is less frequent. However, use of 3D technology does not lead to significant improvements in oncological or functional outcomes.

PATIENT SUMMARY

We reviewed the use of three-dimensional tools for minimally invasive surgery for partial removal of the kidney in patients with kidney cancer. The evidence suggests that these tools have benefits during surgery, but do not lead to significant improvements in cancer control or functional outcomes for patients.

Systematic Review of Comparative Studies of 3D Models for Preoperative Planning in Minimally Invasive Partial Nephrectomy

Background: The employment of 3-dimensional (3D) virtual models of the organs and tumors, obtained from conventional 2-dimensional (2D) imaging (i.e. computed tomography scan and magnetic resonance imaging) have already demonstrated an outstanding potential in urology, especially in renal surgery. Objectives: The aim of this systematic review is to provide an updated focus on the results obtained from the preoperative employment of 3D virtual imaging reconstructions in nephron sparing oncological surgery. Methods: A systematic literature search was conducted in April 2022 using Medline (via PubMed), Embase (via Ovid), Scopus, and Web of Science. The search strategy used PICO criteria and article selection was conducted in accordance with the PRISMA guidelines. The risk of bias and the quality of the articles included were assessed. A dedicated data extraction form was used to collect the data of interest. Results: The initial electronic search identified 471 papers, of which 13 ultimately met the inclusion criteria and were included in the review. 11 studies reported outcomes of virtual models, 2 studies focused on printed 3D models. In these studies, the application of 3D models for preoperative planning has been reported to increase the selective clamping rate and reducing the opening of collecting system, blood loss and loss of renal function. Conclusions: 3D virtual models seem to provide some surgical benefits for preoperative planning especially for complex renal masses. In the next future the continuous evolution of this technology may further increase its field of application and its potential clinical benefit.

Improving accuracy, reliability, and efficiency of the RENAL nephrometry score with 3D reconstructed virtual imaging

OBJECTIVE

To clarify the diagnostic performance of the three-dimensional reconstructed virtual image (3D-RVI) in evaluating RENAL nephrometry score (RENAL-NS).

METHODS

This study included 130 patients who underwent preoperative contrast-enhanced computed tomography (CECT) followed by partial nephrectomy for renal tumors suggestive of renal cell carcinoma. RENAL-NS was calculated prior to the surgery, and tumor resection was performed referring to the score. We retrospectively reviewed preoperative CECT images. We calculated the inter-observer variability of RENAL-NS using 3D-RVI versus two-dimensional (2D) imaging and compared the ability of RENAL-NS using 3D-RVI versus 2D imaging to predict the risk of opening of the urinary collecting system. We also compared the two modalities for the time required to evaluate RENAL-NS.

RESULTS

RENAL-NS evaluated using 3D-RVI showed a higher inter-observer agreement compared to 2D-imaging (r_s = 0.85 vs. r_s = 0.65). The "nearness to sinus" score was more strongly associated with the opening of the urinary collecting system when evaluated using 3D-RVI than 2D-imaging (AUC = 0.71 vs AUC = 0.57, p = 0.016). RENAL-NS using 2D-imaging required a significantly longer time compared to 3D-RVI (p = 0.036).

CONCLUSIONS

Using 3D-RVI improves the accuracy, reliability and efficiency of RENAL-NS evaluation in preoperative assessment and can play an important role in preoperative assessment and intraoperative navigation.

Deep Learning Plus Three-Dimensional Printing in the Management of Giant (>15 cm) Sporadic Renal Angiomyolipoma: An Initial Report

Objective

To evaluate the feasibility and effectivity of deep learning (DL) plus three-dimensional (3D) printing in the management of giant sporadic renal angiomyolipoma (RAML).

Methods

The medical records of patients with giant (>15 cm) RAML were retrospectively reviewed from January 2011 to December 2020. 3D visualized and printed kidney models were performed by DL algorithms and 3D printing technology, respectively. Patient demographics and intra- and postoperative outcomes were compared between those with 3D-assisted surgery (3D group) or routine ones (control group).

Results

Among 372 sporadic RAML patients, 31 with giant ones were eligible for analysis. The median age was 40.6 (18-70) years old, and the median tumor size was 18.2 (15-28) cm. Seventeen of 31 (54.8%) had a surgical kidney removal. Overall, 11 underwent 3D-assisted surgeries and 20 underwent routine ones. A significant higher success rate of partial nephrectomy (PN) was noted in the 3D group (72.7% vs. 30.0%). Patients in the 3D group presented a lower reduction in renal function but experienced a longer operation time, a greater estimated blood loss, and a higher postoperative morbidity. Subgroup analysis was conducted between patients undergoing PN with or without 3D assistance. Despite no significant difference, patients with 3D-assisted PN had a slightly larger tumor size and higher nephrectomy score, possibly contributing to a relatively higher rate of complications. However, 3D-assisted PN lead to a shorter warm ischemia time and a lower renal function loss without significant difference. Another subgroup analysis between patients under 3D-assisted PN or 3D-assisted RN showed no statistically significant difference. However, the nearness of tumor to the second branch of renal artery was relatively shorter in 3D-assisted PN subgroup than that in 3D-assisted RN subgroup, and the difference between them was close to significant.

Conclusions

3D visualized and printed kidney models appear to be additional tools to assist operational management and avoid a high rate of kidney removal for giant sporadic RAMLs.

Robotic ureteral reimplantation for the management of ureterovaginal fistula: four cases at a single center

Background

To describe our initial experience with robotic ureteral reimplantation for the management of ureterovaginal fistulas.

Methods

Between January 2018 and January 2020, four patients received robotic ureteral reimplantation for ureterovaginal fistulas. All patients were diagnosed based on anterograde urography and computed tomography urography (CTU). Follow-up was performed with magnetic resonance urography and renal ultrasound as well as the clinical assessment of symptoms.

Results

The mean age of all patients was 50.3 (range, 37–65) years. The cause of the ureterovaginal fistula in four patients was due to a previous hysterectomy. The mean time from fistula diagnosis to robotic repair surgery was 14.5 (range, 3–36) months. All robotic procedures were successfully performed without intraoperative complications or open conversion. The mean operative time was 137 (range, 116–171) minutes, and the mean estimated blood loss was 25 (range, 10–50) mL. No postoperative complications that were high grade (grade III and IV) occurred within one month of surgery. Patients had the double-J (D-J) stents removed 2 months after surgery and the nephrostomy tubes removed 3 months after the operation. There was a 100% success rate without serious complications, such as the leakage of urine and side progressive hydronephrosis, during the 6 to 24 months of follow-up.

Conclusions

Our initial results and experience showed that robotic ureteral reimplantation for the management of ureterovaginal fistula is safe and feasible.

Three-dimensional virtual planning for nodule resection in solid organs: A systematic review and meta-analysis

OBJECTIVES

To systematically review the effects of 3D-imaging virtual planning for nodule resection in the following solid organs: lung, liver, and kidney.

METHODS

MEDLINE, EMBASE, and Cochrane Library were searched through September 31, 2020 to include randomized and non-randomized controlled studies that compared outcomes of surgical resection of lung, liver, or kidney nodule resection with and without 3D virtual planning with computed tomography. From each article, the mean operation time (OT), mean estimated blood loss (EBL), mean postoperative hospital stay (POHS), and the number of postoperative events (POE) were extracted. The effect size (ES) of 3D virtual planning vs. non-3D planning was extracted from each study to calculate the pooled measurements for continuous variables (OT, EBL, POHS). Data were pooled using a random-effects model.

RESULTS

The literature search yielded 2397 studies and 10 met the inclusion criteria with a total of 897 patients. There was a significant difference in OT between groups with a moderate ES favoring the 3D group (ES,-0.56; 95%CI: 0.91,-0.29; I² = 83.1%; p < .001). Regarding EBL, there was a significant difference between 3D and non-3D with a small ES favoring IGS (ES,-0.18; 95%CI: 0.33,-0.02; I² = 22.5%; p = .0236). There was no difference between the 3D and non-3D groups for both POHS (POHS ES,-0.15; 95%CI: 0.39,0.10; I² = 37.0%; p = .174) and POE (POE odds ratio (OR),0.80; 95%CI:0.54,1.19; I² = 0.0%; p = .0.973).

CONCLUSIONS

3D-imaging planning for surgical resection of lung, kidney, and liver nodules could reduce OT and EBL with no effects on immediate POHS and POE. Improvements in these perioperative variables could improve medium and long-term postoperative clinical outcomes.

Application of three-dimensional image reconstruction technology based on high-resolution CT in pyeloplasty

Background

Three-dimensional (3D) image reconstruction technology is widely used in surgical operations for its intuitive visualization. Pyeloplasty requiresprecise cutting and suturing. The reconstruction technology can accurately determine the location and scope of the stenosis at the junction of the renal pelvis and ureter and the relationship with the surrounding vasculature. The purpose of this article is to retrospective evaluate the application value of image reconstruction technology in pyeloplasty based on high-resolution 3D CT images.

Methods

A total of 20 patients with renal pelvic ureteral junction obstruction admitted to our hospital from August 2019 to August 2020 were selected. In this group, left pyeloplasty was performed in 8 patients and right pyeloplasty in 12 patients. In terms of conditions, there was 1 case with secondary pyeloplasty, 6 cases of patients with kidney stones, 2 cases with renal ectopic blood vessels, 1 case with renal prolapse, 1 case with horseshoe kidney, and 1 case with ureteral polyps. There were 12 males and 8 females, with an average age of 34.65±10.67 years and an average body mass index (BMI) of 22.48±3.03 kg/m². In all patients, 3D CT reconstruction technology was used to guide the formulation of robot-assisted laparoscopic pyeloplasty plans; verify the consistency between the actual operation and the preoperative planning; and observe the operation time, blood loss, postoperative exhaust time, indwelling drainage tube time, and follow-up for comorbidities.

Results

The operation was successful in all 20 patients. The actual operation was 100% consistent with the preoperative planning, the operative time was 160.80±63.26 min, the intraoperative blood loss was 47±30.45 mL, the postoperative exhaust time was 1.15±0.37 days, the drainage tube indwelling time was 4.35±1.50 days, and the average follow-up time was 7.95±3.41 months. There were no complications.

Conclusions

Three-dimensional image reconstruction technology based on high-resolution CT has high clinical application value in the treatment of ureteropelvic junction obstruction (UPJO), which simplifies the operation process and shortens the operation time, and is a valuable tool for auxiliary surgeons in devising the operation plan.

Computed Tomography Radiomics for Predicting Pathological Grade of Renal Cell Carcinoma

Background

Clear cell renal cell carcinoma (ccRCC) is the most common renal cancer and it has the worst prognosis among all renal cancers. However, traditional radiological characteristics on computed tomography (CT) scans of ccRCC have been insufficient to predict the pathological grade of ccRCC before surgery.

Methods

Patients with ccRCC were retrospectively enrolled into this study and were separated into two groups according to the World Health Organization (WHO)/International Society of Urological Pathology (ISUP) grading system, i.e., low-grade (Grade I and II) group and high-grade (Grade III and IV) group. Traditional CT radiological characteristics such as tumor size, pre- and post-enhancing CT densities were assessed. In addition, radiomic texture analysis based on the CT imaging of the ccRCC were also performed. A CT-based machine learning method combining the traditional radiological characteristics and radiomic features was used in the predictive modeling for differentiating the low-grade from the high-grade ccRCC. Model performance was evaluated with the receiver operating characteristic curve (ROC) analysis.

Results

A total of 264 patients with pathologically confirmed ccRCC were included in this study. In this cohort, 206 patients had the low-grade tumors and 58 had the high-grade tumors. The model built with traditional radiological characteristics achieved an area under the curve (AUC) of 0.9175 (95% CI: 0.8765–0.9585) and 0.8088 (95% CI: 0.7064–0.9113) in differentiating the low-grade from the high-grade ccRCC for the training cohort and the validation cohort respectively. The model built with the radiomic textural features yielded an AUC value of 0.8170 (95% CI: 0.7353–0.8987) and 0.8017 (95% CI: 0.6878–0.9157) for the training cohort and the validation cohort, respectively. The combined model integrating both the traditional radiological characteristics and the radiomic textural features achieved the highest efficacy, with an AUC of 0.9235 (95% CI: 0.8646–0.9824) and an AUC of 0.9099 (95% CI: 0.8324–0.9873) for the training cohort and validation cohort, respectively.

Conclusion

We developed a machine learning radiomic model achieving a satisfying performance in differentiating the low-grade from the high-grade ccRCC. Our study presented a potentially useful non-invasive imaging-focused method to predict the pathological grade of renal cancers prior to surgery.

Preoperative 3D reconstruction images for paediatric tumours: Advantages and drawbacks

RATIONALE

Three-dimensional reconstruction (3DR) of preoperative images may improve the presurgical assessment of tumours prior to removal. We aimed to analyse the advantages and discrepancies of preoperative 3DR in paediatric tumours.

METHODS

We conducted a prospective observational study from 2016 to 2019, including patients with thoraco-abdominal tumours having predictable surgical risks on preoperative images (encasement of vessels posing vascular risks, ie, neuroblastic and soft tissue tumours or parenchyma preservation of the invaded organ, ie, liver and kidney). A comparison of 2D/3DR and surgical findings was performed.

RESULTS

Twenty-four patients, with a median age at surgery of 68.2 months (13 days-203 months), were operated on for neuroblastoma (n = 7), renal tumour (n = 7), hepatic tumour (n = 4) and others (n = 6; bone sarcoma of the iliac branch, abdominal lymph nodes of a recurrent testicular germ cell tumour, pseudoinflammatory tumour of the omentum, thoracic lipoblastoma, desmoplastic tumour, solid and pseudopapillar tumour of the pancreas). Reconstruction was of poor quality in two patients with renal tumours because computed tomography (CT) had no excretory phase. Discrepancies between 3DR and surgical findings occurred in two patients, one because of poor assessment of caliceal infiltration by renal nodules and the other because of inadequate reconstruction of renal vein thrombosis. For all the other tumours, 3DR improved the visualisation and precise location of vessels during surgery.

CONCLUSION

High-quality preoperative images are mandatory to provide the best 3DR. In the majority of cases, 3DR is of significant help during surgery to better identify vascular structures within tumours and preserve parenchyma.

3D reconstruction of Wilms' tumor and kidneys in children: Variability, usefulness and constraints

INTRODUCTION

Wilms' tumor (WT) is the most common type of malignant kidney tumor in children. Three-dimensional reconstructions can be performed pre-operatively to help surgeons in the planning phase.

OBJECTIVES

The main objective of this study was to determine the variability of WT segmentation and 3D reconstruction. The secondary objectives were to assess the usefulness of these 3D reconstructions in the surgical planning phase and in the selection of patients for nephron-sparing surgery (NSS).

METHODS

14 scans from 12 patients were manually or semi-automatically segmented by 2 teams using 3D Slicer software. Inter-individual variability of 3D reconstructions was measured based on the Dice index. The utility of 3D reconstructions for the surgical planning was evaluated by 4 pediatric surgeons using a 5-point Likert scale. The possibility of undertaking NSS was evaluated according to the criteria defined in the Umbrella SIOP-RTSG 2016 protocol.

RESULTS

Segmentation of the WT, healthy kidney, pathological kidney, arterial and venous vascularization could be performed for all of the patients in this study. Urinary cavities segmentation could only be performed for 5 out of 14 scans that had a delayed acquisition phase. The mean time required to carry out these segmentations was 8.6 h [3-15 h]. The mean Dice index for all of the scans was good (mean: 0.87; range [0.83-0.91]). Considering each anatomical structure, the Dice index was very good for the WT (mean: 0.95; range [0.91-0.97]) and the healthy kidney (mean: 0.95; range [0.93-0.96]), good for the pathological kidney (mean: 0.87; range [0.69-0.96]) and arterial vascularization (mean: 0.84; range [0.74-0.91]). The Dice index was lower than 0.8 for venous vascularization only (mean: 0.77; range [0.58-0.86]). All the surgeons who were interviewed agreed that the 3D reconstructions were realistic representations and useful for the surgical planning phase. The images reconstructed in 3D allowed most of the criteria defined by the Umbrella SIOP-RTSG 2016 protocol to be evaluated regarding the selection of patients who could benefit from NSS.

CONCLUSION

The inter-individual variability of 3D reconstructions of WT is acceptable. Three-dimensional representation appears to assist surgeons with the surgical planning phase by allowing them to better anticipate the operative risks. 3D reconstructions can also be an additional tool to better select patients for NSS. However, the manual or semi-automatic method used is very time-consuming, making it difficult for a routinely use. Developing techniques to automate this segmentation process, therefore, appears to be essential if surgeons and radiologists are to use it in daily practice.

Three-Dimensional Printing Assisted Laparoscopic Partial Nephrectomy vs. Conventional Nephrectomy in Patients With Complex Renal Tumor: A Systematic Review and Meta-Analysis

Objective: The purpose of this meta-analysis was to systematically assess the influence of three-dimensional (3D) printing technology in laparoscopic partial nephrectomy (LPN) of complex renal tumors. Methods: A systematic literature review was performed in June 2020 using the Web of Science, PubMed, Embase, the Cochrane library, the China National Knowledge Infrastructure (CNKI), and the Wanfang Databases to identify relevant studies. The data relative to operation time, warm ischemic time, intraoperative blood loss, positive surgical margin, reduction in estimated glomerular filtration rate (eGFR), and complications (including artery embolization, hematoma, urinary fistula, transfusion, hematuria, intraoperative bleeding, and fever) were extracted. Two reviewers independently assessed the quality of all included studies, and the eligible studies were included and analyzed using the Stata 12.1 software. A subgroup analysis was performed stratifying patients according to the complexity of the tumor and surgery type or to the nephrometry score. Results: One randomized controlled trial (RCT), two prospective controlled studies (PCS), and seven retrospective comparative studies (RCS) were analyzed, involving a total of 647 patients. Our meta-analysis showed that there were significant differences in operation time, warm ischemic time, intraoperative blood loss, reduction in eGFR, and complications between the LPN with 3D-preoperative assessment (LPN-3DPA) vs. LPN with conventional 2D preoperative assessment (LPN-C2DPA) groups. Positive surgical margin did not differ significantly. Conclusion: The LPN-3DPA group showed shorter operation time and warm ischemic time, as well as less intraoperative blood loss, reduction in eGFR, fewer complications for patients with complex renal tumor. Therefore, LPN assisted by three-dimensional printing technology should be a preferable treatment of complex renal tumor when compared with conventional LPN. However, further large-scale RCTs are needed in the future to confirm these findings.

[Application of preoperative three-dimensional image reconstruction in the treatment of ureteropelvic junction obstruction]

OBJECTIVE

To investigate the value of preoperative three-dimensional image reconstruction in the treatment of ureteropelvic junction obstruction (UPJO).

METHODS

We reviewed data on 40 patients (22 male cases, and 18 female cases) diagnosed with UPJO in Peking University First Hospital from May 2017 to April 2019. The median age was 26.5 years (IQR 23.25-38.75) years. There were 11 patients complicated with ectopic vessels, 14 patients with kidney stones, 3 patients with horseshoe kidney, and 6 patients with obstruction after pyeloplasty. All the patients underwent preoperative enhanced CT scan, and the CT data were reconstructed into three-dimensional image models. The obstruction position of ureteropelvic junction and the relationship between ureteropelvic junction and blood vessels and organs were observed by three-dimensional models to assist planning surgery. Thirty-seven patients underwent laparoscopic pyeloplasty (including 3 cases combined with pyelolithotomy with flexible cystoscope, 1 case combined with pyelolithotomy by sun-style cystoscope, 1 case with laparoscopic ureter resection and anastomosis, 3 cases of laparoscopic pyeloplasty of horseshoe kidney), 2 patients underwent laparoscopic ventral onlay lingual mucosal graft ureteroplasty, and 1 patient underwent robot-assisted laparoscopic pyeloplasty.

RESULTS

Three-dimensional CT image clearly showed the relationship between the obstruction of ureteropelvic junction and blood vessels and organs after three-dimensional reconstruction. The type, diameter, position and direction of the ectopic vessels could be observed clearly before operation according to the three-dimensional reconstruction model, and the number, size, location and shape of renal calculi or other masses, the number of involved renal calyces and the anatomical distribution in the renal pelvis and calyces could be also evaluated preoperatively. After comprehensive analysis of the above information, individualized operation plans were performed on the patients, all the 40 cases were successfully completed with the surgery without any transfer to open surgery. The average operative time was (129.91±37.90) min (range: 75 to 273), the average blood loss was (48.1±78.0) mL (range: 10 to 400), the average hospitality was (5.04±1.99) d (range: 2 to 10), and the average postoperative drainage time was (3.8±1.4) d (range: 2 to 8).

CONCLUSION

The preoperative three-dimensional image reconstruction has a high clinical value in the treatment of ureteropelvic junction obstruction, and it is of great help to assist surgery planning and is worthy of further clinical promotion and application.

Evaluation of Interactive Virtual Reality as a Preoperative Aid in Localizing Renal Tumors

Introduction: A detailed understanding of renal tumor anatomy is required to perform partial nephrectomy. We evaluated the utility of a CT-based interactive virtual reality (iVR) display to assist surgeons' understanding of the precise location of the renal tumor. Methods: CT scans and iVR models of 11 patients with a mean R.E.N.A.L. nephrometry score of 6.9 were evaluated. Seven faculty urologists and six urology residents reviewed CT scans and positioned each tumor onto a digital three-dimensional model of the same kidney, although without the tumor present. A week later, participants repeated the session using both iVR models and CT scans. For both time points, the overlap between the surgeon-inserted tumor and the actual tumor location was calculated. Participants answered a 1 to 10 Likert scale survey to gauge their understanding of renal and tumor anatomy based on CT alone vs CT+iVR. Results: Median tumor overlap for the entire cohort was 28% after CT review and 42% after CT+iVR (p = 0.05); among faculty urologists, for CT+iVR vs CT alone, percentage overlap improved (47% vs 33%, p = 0.033) and the incidence of 0% overlap decreased (19%-4%, p = 0.024), respectively. Among residents, there was no significant difference for either percentage overlap or 0% overlap for CT vs CT+iVR. The percentage overlap for the two tumors with high R.E.N.A.L. nephrometry scores (i.e., 10) increased from 51% to 67% after using CT+iVR (p = 0.039). The combination of CT+iVR was an independent predictor of improved overlap vs CT alone (odds ratio 2.22, 95% confidence interval 1.04-4.78, p = 0.039). Faculty surgeons' survey responses showed an improved understanding of the tumor location and shape with the addition of iVR (p < 0.05). Conclusions: The addition of patient-specific iVR models to standard CT imaging improved the ability of faculty urologists to accurately configure the location of a renal tumor, and improved their understanding of tumor anatomy.

Laparoscopy for living donor left nephrectomy: Comparison of three-dimensional and two-dimensional vision

The main objective of this preliminary study was to evaluate the feasibility and safety of 3-D laparoscopic living donor left nephrectomy (LDLN). The secondary objective was to compare intraoperative and postoperative outcomes between 3-D and 2-D laparoscopic LDLN. All patients who underwent a laparoscopic LDLN from January 2015 to April 2018 in a university center were included. All surgeries were performed by three experienced surgeons. Seventy three patients were included the following: 16 underwent a 3-D laparoscopic LDLN (3-D group), and 57 underwent a 2-D laparoscopic LDLN (2-D group). Operative time and warm ischemia time (WIT) were significantly lower in the 3-D group (operative time: 80.9 ± 10.2 vs 114.1 ± 32.3 minutes in the 3-D and 2-D groups, P = .0002) (WIT: 1.7 ± 0.6 vs 2.3 ± 0.9 minutes in the 3-D and 2-D groups, P = .02). No conversion to open surgery occurred in both groups. Length of hospital stay was significantly shorter in the 3-D group. No major postoperative complications (Clavien ≥ III) occurred. One-year postoperative GFR was similar to 3-D and 2-D groups. Our preliminary study demonstrates that 3-D laparoscopic LDLN is a feasible and safe surgical procedure. Intraoperative and postoperative outcomes were similar in both 2-D and 3-D vision systems, but 3-D vision systems allow reduction in WIT and operative time.

Three-dimensional printing for laparoscopic partial nephrectomy in patients with renal tumors

Objectives

To explore the efficacy of three-dimensional printing physical model-assisted laparoscopic partial nephrectomy (3D-LPN) in patients with renal tumors.

Methods

We retrospectively assessed all patients who underwent LPN with or without 3D-printed physical model assistance from January 2016 to February 2018 at our institution. The demographic characteristics, operative findings, and clinical outcomes from the procedure were collected and analyzed.

Results

Sixty-nine patients underwent 3D-LPN and 58 underwent traditional LPN. The groups showed no differences in demographics, RENAL score, surgical approach, operative time, estimated intra-/postoperative blood loss, increased creatinine level, or complications. In the 3D-LPN group, warm ischemia time was shorter, whereas surgery waiting time was longer, compared with those parameters in the LPN group. Subgroup analysis indicated that for patients with RENAL score ≥8, the 3D-LPN group had significantly shorter warm ischemic time and less intraoperative blood loss than the traditional LPN group. Intra- and postoperative hospital complication rates were similar for 3D-LPN and traditional LPN groups (8.7% vs. 13.7%).

Conclusions

3D printing provides an additional tool to assist with LPN. Use of a 3D model can assist in planning and performance of LPN in patients with RENAL score ≥8.

The Use of 3-Dimensional, Virtual Reality Models for Surgical Planning of Robotic Partial Nephrectomy

OBJECTIVE

To determine whether 3-dimensional virtual reality models of patient-specific anatomy improve outcomes in patients undergoing robotic partial nephrectomy.

MATERIALS AND METHODS

Computed tomography and magnetic resonance imaging scans for 30 patients undergoing robotic partial nephrectomy were converted to 3-dimensional virtual reality models prior to the patient's operation. These models were then viewed on the surgeon's mobile phone pre- and intraoperatively using a Google Cardboard headset to assist in surgical planning. This group was compared to 30 patients who previously underwent robotic partial nephrectomy. We compared operative time, clamp time, estimated blood loss, hospital stay, complications, and margin status between these groups. We used forward selecting multivariate regression models to create the final model controlling for significant demographic and clinical variables.

RESULTS

When controlling for case complexity and surgeon, patients with 3-dimensional, virtual reality-assisted surgical planning had significantly lower operative time (141 minutes vs 201 minutes, P < .0001), clamp time (13.2 minutes vs 17.4 minutes, P = .0274), and estimated blood loss (134 cc vs 259 cc, P = .0233). Patients without 3-dimensional, virtual reality-assisted surgical planning were more likely to have a hospital stay of greater than 2 days (odds ratio 5.1, 95% confidence interval 1.0, 26.4). There were no complications or positive margins noted in the VR group.

CONCLUSION

Use of a 3-dimensional, virtual reality model when performing robotic partial nephrectomy improves key surgical outcome parameters.

Expanding the Indications of Robotic Partial Nephrectomy for Highly Complex Renal Tumors: Urologists' Perception of the Impact of Hyperaccuracy Three-Dimensional Reconstruction

OBJECTIVES

To assess the role of three-dimensional (3D) reconstruction in aiding preoperative planning for highly complex renal tumors amenable to robotic partial nephrectomy (RPN).

MATERIALS AND METHODS

Computed tomography (CT) scans and respective 3D reconstructions of 20 highly complex renal tumors were displayed to the attendees/urologists of the 6th Techno-Urology Meeting ( www.technourologymeeting.com ). These 20 cases had already undergone RPN performed by a single experienced surgeon. The attendees were asked to watch the videos of the CT scans first, and then the respective 3D reconstructions of 5 of the 20 cases who were randomly selected. A purpose-built questionnaire collected responders' surgical experience and surgical indication (RPN versus nephrectomy) after viewing the CT scan and the respective 3D reconstructions.

RESULTS

Twenty expert urologists, 27 young urologists, and 61 residents (total = 108) participated in the study. Five hundred forty-two views of the cases were obtained. Based on CT scans, RPN was indicated in 256 cases (47.2%). After viewing the respective 3D reconstructions, in 148 cases the responders changed their idea: indication to RPN raised in 404 cases (74.5%) (P < .001). The opinions changed regardless of the surgical experience.

CONCLUSIONS

The findings of this study are encouraging, and they might represent a significant step toward the validation of the use of 3D reconstruction for surgical planning in patients undergoing robotic kidney surgery. The use of this technology might translate into a larger adoption of nephron-sparing approach. Further investigation in this area is warranted to corroborate these findings.

[Three-dimensional spatial measurement versus conventional CT planning in laparoscopic partial nephrectomy for renal tumors]

OBJECTIVE

To analyze the advantages of spatial measurement of anatomical parameters in a 3D model in surgical planning for laparoscopic partial nephrectomy (LPN).

METHODS

From February, 2016 to October, 2017, 37 patients diagnosed with T1 renal mass underwent LPN based on 3D reconstruction after enhanced CT scanning using the Uromedix-3D system (group A), and another 38 patients received LPN with conventional CT planning (group B). The anatomical parameters were measured in the reconstructed 3D model and the demographic data, surgical outcome and postoperative data were compared between the two groups.

RESULTS

In group A, the average time for 3D model reconstruction was (29.3∓9.7) min; the length, width and depth of the renal defect in 3D model were 3.2∓1.1 cm, 2.6∓0.9 cm and 1.7∓0.7 cm, respectively; The distance of the tumor from the collecting system was 3.8∓2.2 mm; The mean R.E.N.A.L score of the patients was 7∓1.5, and 3 patients had accessory renal artery and 2 had early branching of the renal artery. LPNs were completed via the retroperitoneal approach in all the 75 patients without conversion to open or total nephrectomy. Group A and group B showed significant differences in warm ischemic time (26.7∓6.4 vs 31.9∓7.0 min), tumor-excision time (8.4∓2.6 vs 10.4∓2.8 min), renal defect suture time (18.3∓3.9 vs 21.5∓3.4 min), 24-h volume of retroperitoneal drainage (88.6∓40.2 vs 134.3∓58.3 mL) and 48-h volume of retroperitoneal drainage (127.9∓54.5 vs 198.1∓86.3 mL), but not in the demographic data, operation time, intraoperative blood loss or postoperative hospital stay.

CONCLUSIONS

3D reconstruction of the renal masses can be completed efficiently and accurately using this system. Compared with conventional CT-based measurement, 3D spatial measurement of the anatomical structures helps to increase the precision in the performance of LPN and reduce the warm ischemia time.

Application of Three-Dimensional Visualization Technology in Laparoscopic Surgery for Pheochromocytoma/Paraganglioma: A Single-Center Experience

OBJECTIVE

To compare the feasibility of three-dimensional visualization technology (3DVT) with that of routine computed tomography (CT) examination during planning of laparoscopic surgery for pheochromocytoma (PHEO) and paraganglioma (PGL) and the effects on operative and postoperative outcomes.

PATIENTS AND METHODS

The clinical data for 36 patients who underwent laparoscopic surgery for PHEO/PGL in our department from January 2016 to April 2017 were analyzed retrospectively. Fourteen patients underwent laparoscopic surgery for PHEO/PGL after preoperative 3DVT-based assessment and 22 after conventional CT examination. The demographic parameters, surgical procedures used, and perioperative outcomes were compared between the two groups. Data were entered into a Microsoft Excel worksheet and analyzed using SPSS version 24.0.

RESULTS

No significant differences were found between the groups with regard to age, gender, body mass index, tumor size, surgical approach, estimated blood loss, mean length of hospital stay, number of hypertensive and hypotensive episodes during surgery, peak blood pressure (BP) values during tumor handling, and minimum values after tumor excision. However, the operating time was significantly shorter and the fluctuations in BP were significantly lower in the 3DVT group.

CONCLUSIONS

3DVT is a feasible and useful preoperative assessment method in patients undergoing laparoscopic surgery for PHEO/PGL. This imaging technique accurately shows the relationship between the tumor and peripheral structures and aids the surgeon's understanding of the anatomic structure in the operative area and in surgical planning.