Robotic Partial Nephrectomy: Scarring and Surgical Clips
Yes, a kidney will always have scarring at the resection site after robotic partial nephrectomy, and surgical clips (typically Hem-o-lok® clips) are routinely placed and will be permanently visible on imaging, even if not specifically mentioned in radiology reports. 1
Internal Kidney Scarring is Universal
All robotic partial nephrectomies create internal scarring at the tumor resection site—the extent depends on the surgical technique used (simple enucleation produces minimal scarring, while wedge or polar resection creates more extensive scarring). 2
The scarring results from the surgical excision of tumor tissue and subsequent renal parenchymal reconstruction, which involves suturing the kidney tissue back together over cellulose bolsters. 3
This internal scarring is a normal and expected consequence of the procedure, not a complication—it represents the healed surgical site where healthy kidney tissue was preserved. 2
Surgical Clips Are Standard and Permanent
Hem-o-lok® clips are routinely placed during robotic partial nephrectomy—typically 6-8 clips per procedure are used to secure No. 0 polyglactin sutures that reinforce the renal parenchyma. 1, 4
These clips are pulled flush against the renal capsule and maintain tight hemostatic compression over the cellulose bolsters placed in the partial nephrectomy bed. 3, 1
The clips are metallic and permanent—they will always be visible on CT scans and X-rays as metallic densities, regardless of whether the radiologist or technician mentions them in the report. 1
Why Clips May Not Be Mentioned in Reports
Surgical clips are an expected normal finding after partial nephrectomy, so radiologists may not specifically comment on them if they appear routine and unremarkable. 1
The presence of clips helps radiologists identify the surgical site during surveillance imaging, but they may only be mentioned if there are concerns about positioning or if the patient's surgical history is unclear. 1
Baseline postoperative imaging at 1 month establishes the normal post-surgical appearance, including clip location and number, which serves as a reference for future comparisons. 1, 4
Critical Distinction: Clips vs. Recurrence
A common pitfall is confusing surgical clips with recurrent tumor on follow-up imaging—clips remain stable in size and position over time, while tumors grow progressively. 1
If new masses or enlarging lesions appear near the surgical site, these warrant investigation for recurrence, but the clips themselves are benign markers of the surgical repair. 1
Additional Internal Materials
Beyond clips, the kidney will contain absorbable sutures (2-zero and No. 0 polyglactin) used for collecting system repair and parenchymal reconstruction—these dissolve over time and are not visible on imaging. 1, 4
Oxidized regenerated cellulose bolsters are placed in the nephrectomy bed to fill the defect and provide hemostasis—these also absorb over time. 3, 1
Hemostatic bioadhesive agents may be applied to the surface in some cases, though not universally used. 1
Imaging Characteristics
Clips do not interfere with MRI imaging in most cases, though some artifact may occur depending on the specific clip material and MRI sequence used. 1
The surgical site may show enhancement on contrast CT or MRI in the early postoperative period due to inflammation and healing, which should not be confused with residual tumor. 2
Functional Implications
The presence of scarring does not impair renal function—what matters for kidney function is the warm ischemia time during surgery (ideally less than 30 minutes), not the scarring itself. 3, 2
Studies show that robotic partial nephrectomy preserves renal function effectively, with median estimated glomerular filtration rate (eGFR) decline of only 8.7-12% at long-term follow-up. 5, 6