Application of Combined Computed Tomography Arteriography, Venography, and Urography in Laparoscopic Partial Nephrectomy With Segmental Artery Clamping

Depiction rate of feeding arteries of renal cell carcinoma on four-dimensional computed tomography angiography

PURPOSE

To retrospectively evaluate the depiction rate of feeding arteries in biopsy-proven clear cell renal cell carcinoma (CCRCC) on four-dimensional computed tomography angiography (4D-CTA) images.

MATERIALS AND METHODS

This study included 22 patients with 22 CCRCC and 30 feeding arteries treated with transcatheter renal artery embolization. The depiction rate of the feeding arteries on preprocedural 4D-CTA was evaluated. Images were acquired by 320-row multi-detector computed tomography (CT) 15‒36 s after starting to inject a contrast agent (600 mg/kg iodine) intravenously into patients at 2.1 s intervals (11 phases). Two board-certified radiologists retrospectively assessed the feeder depiction rate in all 11 phases with reference to the procedural images as the gold standard. Discrepancies were resolved by consultation with a third radiologist.

RESULTS

Among the feeders, 11 (36.7%) were segmental or lobar, and 19 (63.3%) were interlobar or arcuate arteries. The feeder depiction rate was the highest (25 [83.3%] of 30) in the 5th phase (delay, 23.4 s) where the gap in contrast enhancement between the renal artery and cortex was the largest. This was followed by the 6th (23 [76.7%] of 30), 4th (22 [73.3%] of 30]), and 7th (21 [70.0%] of 30) phases. The overall rate of depicting feeding arteries in the 11 phases of 4D-CTA was 28 (93.3%) of 30.

CONCLUSIONS

The depiction rate of CCRCC feeding arteries including lobar or smaller artery branches by 4D-CTA was favorable. The feeding arteries were optimally visualized during the phase with the largest contrast gap between the renal artery and cortex.

Enhancing surgical planning for abdominal tumors in children through advanced 3D visualization techniques: a systematic review of future prospects

Introduction

Preoperative three-dimensional (3D) reconstruction using sectional imaging is increasingly used in challenging pediatric cases to aid in surgical planning. Many case series have described various teams' experiences, discussing feasibility and realism, while emphasizing the technological potential for children. Nonetheless, general knowledge on this topic remains limited compared to the broader research landscape. The aim of this review was to explore the current devices and new opportunities provided by preoperative Computed Tomography (CT) scans or Magnetic Resonance Imaging (MRI).

Methods

A systematic review was conducted to screen pediatric cases of abdominal and pelvic tumors with preoperative 3D reconstruction published between 2000 and 2023.

Discussion

Surgical planning was facilitated through virtual reconstruction or 3D printing. Virtual reconstruction of complex tumors enables precise delineation of solid masses, formulation of dissection plans, and suggests dedicated vessel ligation, optimizing tissue preservation. Vascular mapping is particularly relevant for liver surgery, large neuroblastoma with imaging-defined risk factors (IDRFs), and tumors encasing major vessels, such as complex median retroperitoneal malignant masses. 3D printing can facilitate specific tissue preservation, now accessible with minimally invasive procedures like partial nephrectomy. The latest advancements enable neural plexus reconstruction to guide surgical nerve sparing, for example, hypogastric nerve modelling, typically adjacent to large pelvic tumors. New insights will soon incorporate nerve plexus images into anatomical segmentation reconstructions, facilitated by non-irradiating imaging modalities like MRI.

Conclusion

Although not yet published in pediatric surgical procedures, the next anticipated advancement is augmented reality, enhancing real-time intraoperative guidance: the surgeon will use a robotic console overlaying functional and anatomical data onto a magnified surgical field, enhancing robotic precision in confined spaces.

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.

Comparison of three dimensional reconstruction and conventional computer tomography angiography in patients undergoing zero-ischemia laparoscopic partial nephrectomy

Background

With the development of three dimensional (3D) reconstruction and printing technology, it has been widely using in the field of urology. However, there have been few studies reporting the role of 3D reconstruction in zero-ischemia partial nephrectomy (PN). The aim of this study was to assess the role of 3D reconstruction and conventional computer tomography angiography (CTA) in zero-ischemia laparoscopic partial nephrectomy (LPN).

Methods

A total of 60 consecutive patients undergoing zero-ischemia LPN between October 2017 and March 2018 who underwent CTA (CTA group including 30 patients) and 3D reconstruction (3D group including the remaining 30 patients) preoperatively were included. 3D reconstruction and CTA images were prepared which were used to demonstrate the number and spatial interrelationships of the location of renal tumors and tumor feeding arteries. These radiological findings were directly correlated with intraoperative surgical findings at laparoscopy. Baseline, perioperative variables and the rate of accurate tumor feeding artery orientation were compared between groups.

Results

All LPNs were completed without conversion to renal hilar clamping or open surgery. Preoperative 3D reconstruction identified that 15 patients had only one tumor feeding artery, 12 had two, and another 3 had three, while the conventional CTA revealed that 22 patients had one tumor feeding artery, 8 had two (P > 0.05). The mean operation time was shorter and estimated blood loss was less in the 3D group (P < 0.05) and the rate of accurate tumor feeding artery dissection was higher in the 3D group (91.7%) in comparison with the CTA group (84.2%). The baseline characteristics and renal function outcomes had no statistical differences between groups.

Conclusions

3D reconstruction can provide comprehensive information for the preoperative evaluation and intraoperative orientation about tumor feeding arteries that may facilitate tumor resection during zero-ischemia LPN for renal tumors.

"Polar flip" technique for transperitoneal laparoscopic partial nephrectomy - Evolution of a novel technique for posterior hilar tumors

Posterior hilar renal tumor extirpation by partial nephrectomy is a unique challenge for transperitoneal laparoscopy. We describe our novel technique of “polar flip” for these tumors. Kidney is rotated by around 45 -60 degrees after mobilisation so that lower pole faces anteriorly and upper pole faces posteriorly, thereby exposing the posterior surface for maneuverability. Technical highlights are hilar control, complete kidney mobilisation, initial flipping with dissection in Gil Vernet's plane to clip posterior segmental renal artery, en mass hilar clamping in normal lie, polar flipping, dissection in Gil Vernet's plane till renal sinus fat, completion of tumor excision, selective vascular ligation, renorhaphy and nephropexy.

Delayed enhancement of the peritumoural cortex in clear cell renal cell carcinoma: correlation with Fuhrman grade

AIM

To assess the delayed enhancement of the peritumoural cortex (DEC) sign in clear cell renal cell carcinoma (ccRCC), and investigate a possible correlation among DEC and Fuhrman grade.

MATERIALS AND METHODS

This retrospective study included 506 patients with 511 histopathologically proven ccRCCs evaluated by computed tomography (CT) angiography. DEC was detected and compared in groups divided by Fuhrman grades (low grade: 1 and 2, high grade: 3 and 4) using univariate and multivariate analyses.

RESULTS

DEC was detected in 89 of 511 (17.4%) ccRCCs (grade 1: 5.7%, 2/35; grade 2: 16.2%, 70/433; grade 3: 31.4%, 11/35; grade 4: 75%, 6/8; p<0.001). The incidence was higher in high-grade ccRCCs (39.5%, 17/43) than in low-grade ccRCCs (15.4%, 72/468; p<0.001). In multivariate analysis, tumour size >5.4 cm (p<0.001, odds ratio [OR]=3.57, 95% confidence interval [CI]: 1.76-7.23) and detection of DEC (p=0.021, OR=2.33, 95% CI: 1.13-4.80) were independent predictors of high-grade ccRCC. For all ccRCCs, the area under the receiver operating characteristic (ROC) curve (AUC) of DEC in predicting high-grade ccRCC was 0.62 (95% CI: 0.53-0.72) with 39.5% sensitivity and 84.6% specificity, while for ccRCCs of >5.4 cm diameter, the AUC was 0.66 (95% CI: 0.52-0.80) with 68.4% sensitivity and 62.7% specificity.

CONCLUSIONS

The DEC sign may predict aggressive biological behaviour of ccRCC, irrespective of tumour size.

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

PURPOSE

To compare the effectiveness and safety of individualized three-dimensional visualization technology (3DVT) on surgical planning and perioperative outcomes in laparoscopic partial nephrectomy (LPN) for renal cell carcinoma (RCC) with routine computed tomography (CT) examination in the treatment of renal tumor.

METHODS

From May 2015 to March 2016, a total of 94 patients with cT1 RCC who underwent surgical treatment in our department were analyzed retrospectively. Among these patients, a total of 49 cases received LPN with operation plan based on 3DVT. Surgical plan was obtained by virtual operation and morphometry on 3D reconstruction model. The remaining 45 cases received surgical treatment with traditional CT examination. Patient demographic, surgical outcome, and postoperative parameters were compared between these two groups.

RESULTS

No significant difference was found in blood loss volume, postoperative complication, selective clamping success rate, changes in postoperative renal function, and operative and ischemic time between the two groups. However, when handling complicated tumor with R.E.N.A.L score ≥8, operation time (126.7 ± 36.4 versus 154.8 ± 34.7, P = .018) and occurrence of postoperative urinary leak (0 versus 4, 0% versus 22.2%, P = .033) were diminished significantly in the 3DVT group.

CONCLUSIONS

3DVT provided precise information of anatomical structure in the operative area and reliable guidance for preoperative plan design. Our results indicated that 3DVT facilitated accurate visible image-guided tumor resection with ideal renal function preservation in LPN for renal tumor of high complexity.

A model for assuring clamping success during laparoscopic partial nephrectomy with segmental renal artery clamping

OBJECTIVES

A model for assuring clamping success was established for laparoscopic partial nephrectomy (LPN) with segmental renal artery clamping (SRAC).

MATERIALS AND METHODS

Patients (n = 107; December 2009-September 2011) who underwent LPN with SRAC dependent on the experience of the surgeon and CTA were retrospectively reviewed to determine the optimal characteristics of target arteries. After multiple logistic regression analysis, variables used to build a nomogram were selected using a backward elimination scheme. A model for a clamping program customized to the patient was designed. The surgical outcomes of patients (n = 141; October 2011-June 2014) who subsequently underwent LPN-SRAC with the applied model were compared with those of the first group of patients.

RESULTS

Five potential predictors were initially assessed: segmental renal artery angle, target artery diameter, and distance (d) to the abdominal aorta, renal hilum (d RH), and kidney midline (d KML). The regression equation was set up as: [Formula: see text]Comparing the patient groups, those for whom the new SRAC model was applied had a significantly better success rate of clamping (P < 0.001), less total operative time (P < 0.001), and less operative blood loss (P = 0.042). No obvious differences were observed in time of warm ischemia, postoperative hospitalization, RENAL nephrometry score, or number of final clamped branches.

CONCLUSIONS

The model for assuring clamping success was helpful in designing an SRAC program and thus benefiting the LPN procedure.

Who needs further evaluations to diagnose upper urinary tract urothelial cancers among patients with abnormal findings by enhanced CT?

Objective

We evaluated who would need further evaluations such as retrograde pyelography (RP) and/or ureteroscopy to diagnose upper urinary tract urothelial cancers (UUTUCs) when abnormal findings for the upper urinary tract (UUT) were detected by enhanced computed tomography (CT).

Methods

We retrospectively analyzed 125 patients who underwent enhanced CT for various reasons and had abnormal findings for the UUT. Patients whose tumors were suspected to be of extraureteral origin were excluded. All patients received RP and/or ureteroscopy to evaluate the UUTUCs.

Results

The median age of the 125 patients was 70 years and gross hematuria (26.4%) was the most frequently observed symptoms. RP, ureteroscopy and both were performed for 121, 59 and 55 patients, respectively. CT revealed tumor-like lesions in 58 patients and the other patients had non-tumor-like lesions. UUTUCs were found in 43 (34.4%) of the 125 patients. All of them had tumor-like lesions on CT. In 58 patients who had tumor-like lesions on CT, univariate and multivariate analyses revealed that tumor diameter and tumor enhancement were significant predictive factors for UUTUCs. ROC curve analysis of enhanced CT to diagnose UUTUCs revealed that a tumor diameter of 18 mm was the best cutoff point. The sensitivity, specificity and accuracy were 90.0%, 98.8% and 92.7% for RP and 95.5%, 100% and 97.1% for ureteroscopy, respectively. Both of them had high sensitivity, specificity and accuracy.

Conclusion

We should decide to evaluate the UUT according to the tumor diameter on enhanced CT. When we evaluate the UUT in patients with tumor diameters of less than 20 mm, ureteroscopy is recommended.

Laparoscopic upper-pole heminephrectomy for duplicated renal collecting system with superselective artery clamping using virtual partial nephrectomy analysis of Synapse Vincent: A case report

A 22-year-old woman was diagnosed with a duplicated renal collecting system with hydronephrosis and parenchymal loss in the upper pole of the left kidney. She underwent laparoscopic left upper-pole nephrectomy. Although a complex hilar vascular anatomy was identified during the operation, preoperative three-dimensional computed tomographic reconstruction using a three-dimensional image analysis device (Synapse Vincent; Fuji Medical Systems, Tokyo, Japan) greatly helped to accurately identify the anatomical renal hilum. For further detail, virtual partial nephrectomy analysis using a Voronoi decomposition was used to visualize the area supplied by a selected arterial branch including the atrophic cleavage line. We controlled the bleeding with selective clamping and safely carried out upper-pole heminephrectomy according to the preoperative plan.