Multidetector CT imaging of complications after laparoscopic nephron-sparing surgery

Pre-gerotal fat patch-A novel alternative to haemostatic agents during partial nephrectomy

Objective

This study aimed to determine if using a pre-gerotal fat patch at open partial nephrectomy (PN) as a haemostatic bolster is a viable alternative to using synthetic haemostatic agents.

Materials and methods

Human Research Ethics Committee approval was obtained for audit of a prospectively kept database from July 2012 to July 2021, which followed outcomes of patients who received a low-tension pre-gerotal fat patch renorrhaphy at open PN. Patient demographics, intraoperative measures, histological outcomes and post-operative complications were analysed. Using a retroperitoneal approach, the peritoneum was mobilised and a vascularised pedicle of pre-gerotal fat was rotated in the direction of the kidney. Routine definition of the hilum, clamping of the hilar vessels and dissection of mass followed. After watertight closure and haemostasis, the harvested pre-gerotal fat patch was placed over the defect and secured using low-tension renorrhaphy. Two-layer closure of the abdominal wall with placement of a drain was routine.

Results

A total of 55 patients underwent open PN. Mean age was 60.4 (35-77) years. There were 38 men and 17 women, and 32 right and 23 left PNs. Mean mass size was 31.9 mm (10-95 mm) and collecting system was breached in 36.5% of cases. One patient (1.9%) suffered a Clavien-Dindo IIIb complication requiring return to theatre and transfusion due to a bleed from an intercostal artery. There were no renal bed bleeds, urine leaks or urine fistulas detected. Mean intraoperative blood loss was 355 mL (50-1500 mL) and mean post-operative creatinine increased by 10.7 μmol/L (51-172 μmol/L). Mean follow up was 40.2 (4-109) months.

Conclusion

Utilisation of an anatomical pre-gerotal fat patch to provide pressure at the renorrhaphy site during open PN is an effective technique to assist with surgical haemostasis. This simple technique avoids the costs of haemostatic agents, whilst adding minimal operating time to procedures.

Complications after Nephron-sparing Interventions for Renal Tumors: Imaging Findings and Management

The two primary nephron-sparing interventions for treating renal masses such as renal cell carcinoma are surgical partial nephrectomy (PN) and image-guided percutaneous thermal ablation. Nephron-sparing surgery, such as PN, has been the standard of care for treating many localized renal masses. Although uncommon, complications resulting from PN can range from asymptomatic and mild to symptomatic and life-threatening. These complications include vascular injuries such as hematoma, pseudoaneurysm, arteriovenous fistula, and/or renal ischemia; injury to the collecting system causing urinary leak; infection; and tumor recurrence. The incidence of complications after any nephron-sparing surgery depends on many factors, such as the proximity of the tumor to blood vessels or the collecting system, the skill or experience of the surgeon, and patient-specific factors. More recently, image-guided percutaneous renal ablation has emerged as a safe and effective treatment option for small renal tumors, with comparable oncologic outcomes to those of PN and a low incidence of major complications. Radiologists must be familiar with the imaging findings encountered after these surgical and image-guided procedures, especially those indicative of complications. The authors review cross-sectional imaging characteristics of complications after PN and image-guided thermal ablation of kidney tumors and highlight the respective management strategies, ranging from clinical observation to interventions such as angioembolization or repeat surgery. Work of the U.S. Government published under an exclusive license with the RSNA. Online supplemental material and the slide presentation from the RSNA Annual Meeting are available for this article. Quiz questions for this article are available in the Online Learning Center. See the invited commentary by Chung and Raman in this issue.

Application of Contrast-Enhanced Ultrasonography (CEUS) in the Assessment of Kidney Wound Recovery After Nephron-Sparing Surgery

Purpose

To investigate feasibility, repeatability and usefulness of contrast-enhanced ultrasonography (CEUS) in the assessment of kidney wound recovery after laparoscopic nephron-sparing surgery (LNSS) or robot-assisted nephron-sparing surgery (RANSS) and preliminarily research the clinical factors associated with the length of extravasation (LOE).

Patients and Methods

From April 2019 to January 2020, 130 patients that underwent LNSS or RANSS in our hospital were included, and 90 patients (90/130) received CEUS examinations each one day from the postoperative day 1. The discovery of the cessation of contrast medium extravasation from the renal wound was the primary endpoint named "ultrasonic healing", and LOE ranged from the day of surgery to "ultrasonic healing". Patient, tumor, perioperative factors and LOE were collected. Univariate analysis and multivariate linear regression analysis were applied for the determination of factors associated with LOE.

Results

The average postoperative LOE was 1.76 days (standard deviation, 1.115; 95% confidence interval: 1.52-1.99). Ultrasonic healing within three days was observed in 95.6% patients (86/90). Univariable and multivariable analyses showed that R and A components in R.E.N.A.L. nephrometry score were associated with LOE. Anterior location and R component score of 2 (tumor size>4cm) were related to longer LOE than posterior location and R score of 1 (tumor size<4cm). The incidence of complications in patients with LOE over one day was higher than those with LOE of one day.

Conclusion

CEUS was feasible, repeatable and useful in the assessment of kidney wound recovery. Tumor size and location were related to LOE after minimally invasive nephron-sparing surgery (MINSS). Length of stay after MINSS within three days might be relatively safe.

Renal artery embolization for iatrogenic renal vascular injuries management: 5 years' experience

OBJECTIVE

Evaluate the efficacy and safety of renal artery embolization (RAE) for iatrogenic renal vascular injuries (IRVI) management at Fondazione Policlinico Universitario "A. Gemelli" IRCCS, in the last 5 years.

METHODS

Retrospective analysis of all RAE procedures performed from January 2013 to December 2017. Patients-related (age, sex, vascular variants, hemoglobin and serum creatinine), IRVI-related (type and vascular level of IRVI, presence and extension of hematoma), management-related (temporal interval between diagnostic imaging and RAE) and procedure-related (embolic materials, technical success, clinical success and complications) parameters were evaluated.

RESULTS

28 RAE procedures performed on 28 patients (21 males; 7 females) were included. 19/28 patients had pseudoaneurysm, 7/28 active bleeding and 1/28 arteriovenous fistula; 4/28 patients had a combination of 2 IRVI.The extent of perirenal hematoma showed correlation with the cause of IRVI (p = 0.028).Technical success was achieved in all patients whereas clinical success in 25/28 (89.3%), with 3 patients requiring re-treatment. Minor complications were observed during 2/28 (7.1%) endovascular procedures. No major complications occurred. A longer procedural time was observed in patients with lower pre-procedural levels of hemoglobin (p = 0.016).No differences were found in mean serum creatinine (p = 0.23) before and immediately after treatment, while values of creatinine at 1 week from the procedure were significantly lower (p = 0.04).

CONCLUSION

RAE is safe and effective for the management of iatrogenic IRVI showing high technical and clinical success rate and low complication rate.

ADVANCES IN KNOWLEDGE

Low pre-procedural hemoglobin levels increase procedural duration time. Glue alone or in combination with other materials is as safe as coils.

Surgical margin follow-up after nephron-sparing surgery: the possible role of CEUS

PURPOSE

To evaluate the possible role of CEUS in the management of patients who underwent nephron-sparing surgery (NSS) and presented questionable findings on the surgical margins at the CECT follow-up exam.

METHODS

In our retro-prospective study, we included 952 patients with small renal masses (SRMs) treated with NSS between 2012 and 2015 and followed with CECT for at least 3 years at Careggi University Hospital. Twenty-two of them presented solid masses on the site of surgery with questionable enhancement at CECT and were further studied with CEUS. This examination was followed by a quantitative analysis of the enhancement pattern.

RESULTS

Out of the 22 masses, 18 were considered possible granulomas, presenting slow wash-in and low enhancement peaks compared to the surrounding parenchyma and persistent delayed wash-out at CEUS. Four lesions presented a suspicious malignant enhancement pattern, with rapid wash-in, high peak and rapid wash-out. In accordance with instructions from the urologist, the first group of 18 patients was strictly monitored, revealing that the mass dimensions and enhancement pattern were stable for at least 3 years of follow-up, while the other 4 patients underwent a second intervention and their masses were confirmed as tumor recurrence at the histopathological evaluation.

CONCLUSIONS

CEUS can play a key role in the surgical margin follow-up after NSS when a suspicious enhancing mass is detected by CECT, giving an accurate depiction of the enhancement pattern and thus helping the clinician in the management of the patient.