311Archivio Italiano di Urologia e Andrologia 2016; 88, 4 ORIGINAL PAPER The role of intraoperative ultrasound in small renal mass robotic enucleation Roberta Gunelli 1, Massimo Fiori 1, Cristiano Salaris 1, Umberto Salomone 1, Marco Urbinati 1, Vici Alexia 1, Teo Zenico 1, Mauro Bertocco 2 1 Urology Unit, Forlì Hospital, Romagna Local Health Service, Italy; 2 Radiology Unit, Romagna Local Health Service, Italy. Introduction: As a result of the growing evidence on tumor radical resection in literature, simple enucleation has become one of the best techniques associated to robotic surgery in the treatment of renal neoplasia, as it guarantees minimal invasiveness and the maximum sparing of renal tissue, facilitating the use of reduced or zero ischemia techniques during resection. The use of a robotic ultrasound probe represents a useful tool to detect and define tumor location, especially in poorly exophytic small renal mass. Materials and methods: A total of 22 robotic enucleations were performed on < 3 cm renal neoplasias (PADUA score 18 Pz 6/7 e 4 Pz 8) using a 12-5 MHz robotic ultrasound probe (BK Drop-In 8826). Results: Once kidney had been isolated from the adipose capsule at the site of the neoplasia (2), the exact position of the lesion could be easily identified in all cases (22/22), even for mostly endophytic lesions, thanks to the insertion of the ultrasound probe through the assistant port. Images were produced and visualized by the surgeon using the TilePro feature of the DaVinci surgical system for producing a picture-in-picture image on the console screen. The margins of resection were then marked with cautery, thus allowing for speedy anatomical dissection. This reduced the time of ischemia to 8 min (6-13) and facilitated the enucleation technique when performed without clamping the renal peduncle (6/22). No complications due to the use of the ultrasound probe were observed. Conclusions: The use of an intraoperative robotic ultrasound probe has allowed for easier identification of small, mostly endophytic neoplasias, better anatomical approach, shorter ischemic time, reduced risk of pseudocapsule rupture during dissection, and easier enucleation in cases performed without clamping. It is noteworthy that the use of intraoperative ultrasound probe allows mental reconstruction of the tumor through an accurate 3D vision of the hidden field during surgical dissection. KEY WORDS: Robotic ultrasound probe; Renal tumor; Simple enucleation; Psychomotor skills. Submitted 15 November 2016; Accepted 15 December 2016 Summary No conflict of interest declared. (SE) is one of the partial nephrectomy techniques that mostly combines functional sparing with radical tumor resection (1-3). In addition, NSS has been encouraged by the recently introduced robotic technique for the conservative treat- ment of renal neoplasias, assuring minimal invasiveness through the sparing of renal tissue and enabling the use of reduced or zero ischemia techniques during surgery. In the present paper we report our experience of the use of intraoperative ultrasound imaging in SE, showing how, besides providing more accurate anatomic detec- tion of neoplasias, it may improve the surgeon’s spatial proprioception, thus facilitating SE performance. MATERIALS AND METHODS Since April 2013 we have performed in our Unit a total of 22 robotic enucleations on < 3 cm renal tumor (PADUA score 18 Pz 6/7 e 4 Pz 8) through a 12-5 MHz robotic probe (BK Drop-In 8826) (Figure 1). We used the DaVinci Xi system in the three-armed con- figuration, connected to a 5-mm port utilized for suction and retraction of the bowel, and a 12-mm assistant port for inserting the drop-in ultrasound probe and for apply- ing the vascular bulldog clamps and the Hem-o-lok clips. A ProART robotic trasducer 8826 (BK Medical) was used for the intraoperative ultrasonography. The TilePro was selected to observe the images on the robotic console, which allowed simultaneous vision of both the operative field and the ultrasound images (4). The probe was managed by the proGrasp forceps; image quality was optimal also thanks to the large field of view. Tumor excision was performed with scissors and the ProGrasp forceps (Intuitive Surgical). No patient had positive surgical margins detected at the pathologic examination. After excision, the renal cortex was closed using the sliding clip renorrhaphy technique (5). RESULTS Once kidney had been isolated from the adipose capsule at the site of the neoplasia (2), the exact position of the lesion could be easily identified in all cases (22/22), even for mostly endophytic lesions. DOI: 10.4081/aiua.2016.4.311 Presented at 20th National Congress SIEUN, Sciacca 2016 INTRODUCTION The widespread use of little invasive imaging tools such as ultrasound has lead to a growing number of diagnosed small renal masses treatable with nephron sparing sur- gery (NSS) in the past decades. On the basis of literature evidence, simple enucleation Gunelli-The Role of Intraoperative Ultrasound _Stesura Seveso 09/01/17 10:06 Pagina 311 Archivio Italiano di Urologia e Andrologia 2016; 88, 4 R. Gunelli, M. Fiori, C. Salaris, U. Salomone, M. Urbinati, Vici Alexia, T. Zenico, M. Bertocco 312 The margins of resection were marked with cautery allowing for speedy anatomical dissection, reducing either time of ischemia to 8 min (6-13) or facilitating enucleation when performed without clamping the renal peduncle (6/22). No complications due to the use of the ultrasound probe were observed. DISCUSSION A comparison of the different types of intraoperative ultrasound probe has shown that handling issues of laparoscopic probes impede an accurate spatial evalua- tion of the tumor, while robotic drop-in probes com- bined with ProGrasp forceps enable fast and efficacious ultrasound exploration on 3D planes (6). In addition, while assistant-controlled laparoscopic probes limit the autonomy of the surgeon, only robotic drop-in probes can be handled directly by the surgeon at the console. Picture-in-picture vision technology (TilePro) on the DaVinci robotic system enables routine simultaneous live vision of both operation field and ultrasound images (Figure 2), while the attached surgeon-controlled drop- in ultrasound probe improves the operator’s sensation of the tool. A possible limitation might be that the methodology is highly operator-dependent: adequate ultrasound imag- ing training should therefore be included in the opera- tor’s preparation. The presence of a radiologist in the ini- tial phases of the training might accelerate the learning curve itself. In a recently published study (7) 87% of interviewees highlighted the potential usefulness of augmented reali- ty, especially during RAPN for detecting the neoplasia, and during mass resection. As yet, however, such tech- nology has not been insufficiently mastered to be trans- ferred to clinical practice (8). It has also been suggested to display overlapped 3D images using the open source processing software (OsiriX) on the surgeon’s console screen through TilePro display for identifying the tumor and vascularization sites, and performing a selective arterial clamping. The combination of this technique with the use of an ultra- sound probe will allow for an accurate drawing of the neoplasia profile (9). Augmented reality techniques, however, are still far from being perfect (10): since augmented reality cannot be used in fine anatomy until adequate technique develop- ment and mastering has been accomplished, it is all the more crucial to optimize the use of a modality which is safe and reproducible, such as intraoperative ultrasound, possibly implemented by the contrast enhanced ultra- sound (CEUS). In our experience, both the easily-handled ultrasound probe and the freedom of movement of the robotic tool have enabled the correct vision of the morphology espe- cially in the deep planes, indicating the best tumor dis- section way, reducing time, risk of pseudocapsule rup- ture during dissection, and ultimately surgical invasive- ness (11). A possible limitation of the methodology might be the application of the ultrasound probe to the renal parenchy- ma after it has been removed from the adipose capsule, especially in case of high renal sclerolipomatosis. Despite the easier handling of the ultrasound probe and the more focused dissection of the sclerolipomatosic cap- sule thanks to the CT scan images, a higher chance of bleeding and a longer operating time indisputably repre- sent major weaknesses. Future use of CEUS will partly overcome these issues. Efficacy of CEUS has been demonstrated by several stud- ies: ultrasound scan can be performed without adipose capsule removal, limiting the dissection of the capsule to the precise site of the neoplasia (12). Evaluation of renal vascularization by means of CEUS has also been described. This methodology assists zero- ischemia partial nephrectomy techniques providing sev- eral more advantages than the fire-Fly technology, including non defatted kidney, good control of medullary blood flow, no toxicity (potential risk of aller- gic reactions to sodium iodide). RAPN was performed with selective clamping and evi- dence of a nonperfused segment of kidney (occlusion angiography) using intraoperative CEUS (13-14). Evidence has been reported on the higher safety of selec- tive ischemia than total ischemia (15). To optimize this technique, the use of a robotic ultrasound probe repre- sents a useful tool to detect and define tumors, especially in poorly exophytic small renal mass, which is usually dif- ficult to identify, and to better assess vascularization. It is noteworthy that the use and the easy handling of the ultrasound probe result in a more accurate identification of the neoplasia site, and in the improvement of psy- chomotor skills, in particular visuospatial skills, enabling a 3D mental image of the tumor with defined profiles, depth and relationship with other structures (16). Figure 1. Ultrasound robotic probe. Figure 2. Picture-in- picture vision technology (TilePro). Gunelli-The Role of Intraoperative Ultrasound _Stesura Seveso 09/01/17 10:06 Pagina 312 The ability to build a mental image of the neoplasia improves both accuracy and awareness of the surgeon’s gesture, consequently optimizing execution time, reduc- ing warm ischemia time (WIT), and facilitating SE, part- ly compensating the lack of force feedback, which is still a major limitation in robotic technology. CONCLUSIONS The use of a robotic ultrasound probe has allowed easier identification of small, mostly endophytic neoplasias, better anatomical approach, shorter ischemic time, reduced risk of pseudocapsule rupture during dissection and easier enucleation in cases performed without clamping. Reduced WIT and intraoperative ultrasound allowed accurate excision with sparing of normal parenchyma in an NSS perspective. Ultrasound methodology using contrast medium will be the natural evolution of intraoperative ultrasound in mininvasive robotic surgery. The major oncological and function sparing results are obtained through the combination of the benefits derived from all available imaging techniques: drop-in ultrasound probe for identifying and mentally recon- structing the neoformation, CEUS for reducing time and avoiding bleeding in case of sclerolipomatosis, fire-Fly for an intuitive evaluation of the exact ischemia area, and virtual reality in the near future. Interestingly, such ultimate technologies have not suc- ceeded in superseding the human being: rather, in this way greater importance is conveyed to the surgeon him- self who employs such techniques for a more compre- hensive 3D mental vision which includes also depth. REFERENCES 1. Carini M, Minervini A, Masieri L, et al. Simple Enucleation for the Treatment of PT1a Renal Cell Carcinoma: Our 20-Year Experience. Eur Urol. 2006; 50:1263-1271. 2. Alenezi A, Motiwala A, Eves S, et al. Robotic assisted laparoscop- ic partial nephrectomy using contrast-enhanced ultrasound scan to map renal blood flow, Int J Med Robot. 2016 Mar 7. doi: 10.1002/rcs.1738 3. Longo N, Minervini A, Antonelli A, et al. Simple enucleation ver- sus standard partial nephrectomy for clinical T1 renal masses: Perioperative outcomes based on a matched-pair comparison of 396 patients (RECORd project) EJSO 2014; 40:762-768. 4. Rogers CG, Laungani R, Bhandari A, et al. Maximizing console surgeon independence during robot-assisted renal surgery by using the Fourth Arm and TilePro. J Endourol. 2009; 23:115-121. 5. Benway BM, Wang AJ, Cabello JM, Bhayani SB. Robotic partial nephrectomy with sliding-clip renorrhaphy: technique and outcomes. Eur Urol. 2009; 55:592-599. 6. Kaczmarek BF, Sukumar S, Kumar RK, et al. Comparison of Robotic and Laparoscopic Ultrasound Probes for Robotic Partial Nephrectomy. Endourol. 2013; 27-9:1137-1140. 7. Hughes-Hallett A, Mayer EK, Pratt P, et al. The current and future use of imaging in urological robotic surgery: a survey of the European Association of Robotic Urological Surgeons. Int J Med Robotics Comput Assist Surg. 2015; 11:8-14. 8. Cheung CL, Wedlake C, Moore J, et al. Fused video and ultra- sound images for minimally invasive partial nephrectomy: a phan- tom study. Med Image Comput Comput Assist Interv. 2010; 13:408- 15. 9. Furukawa J, Miyake H, Tanaka K, et al. Console-integrated real- time three-dimensional image overlay navigation for robot-assisted partial nephrectomy with selective arterial clamping: early single- centre experience with 17 cases. Int J Med Robotics Comput Assist Surg. 2014; 10:385-390. 10. Hughes-Hallett A, Pratt P, Mayer E, et al. Using preoperative imaging for intraoperative guidance: a case of mistaken identity. Int J Med Robot. 2016; 12:262-7. 11. Kaczmarek BF, Sukumar S, Petros F, et al. Robotic ultrasound probe for tumor identification in robotic partial nephrectomy: Initial series and outcomes. Int J Urol. 2013; 20:172-176. 12. Curtiss KM, Ball MW, Gorin MA, et al. Perioperative outcomes of robotic partial nephrectomy for intrarenal tumors. J Endourol. 2015; 29:3. 13. Rao AR, Gray R, Mayer E, et al. Occlusion Angiography Using Intraoperative Contrast-enhanced Ultrasound Scan (CEUS): A novel technique demonstrating segmental renal blood supply to assist zero-ischaemia robot-assisted partial nephrectomy. Eur Urol. 2013; 63:913-919. 14. Alenezi A, Karim O. Role of intra-operative contrast-enhanced ultrasound (CEUS) in robotic-assisted nephron-sparing surgery. J Robotic Surg. 2015; 9:1-10. 15. Gill IS, Patil MB, de Castro Abreu AL, et al. Zero ischemia anatomical partial nephrectomy: a novel approach. J Urol. 2012; 187:807-815. 16. Nicholls D, Sweet L. Psychomotor skills in medical ultrasound imaging - An analysis of the core skill set. J Ultrasound Med. 2014; 33:1349-135. 313Archivio Italiano di Urologia e Andrologia 2016; 88, 4 The role of intraoperative ultrasound in small renal mass robotic enucleation Correspondence Roberta Gunelli, MD Massimo Fiori, MD Cristiano Salaris, MD Umberto Salomone, MD Marco Urbinati, MD Vici Alexia, MD Teo Zenico, MD Urology Unit, Forlì Hospital, Romagna Local Health Service, Forlì, Italy Mauro Bertocco, MD Radiology Unit, Forlì Hospital. Romagna Local Health Service, Forlì, Italy Gunelli-The Role of Intraoperative Ultrasound _Stesura Seveso 09/01/17 10:06 Pagina 313