Laparoscopic ultrasonography

A Systematic Review of Laparoscopic Ultrasonography During Laparoscopic Cholecystectomy

We aim to investigate the potential of laparoscopic ultrasonography (LUS) as a replacement for intraoperative cholangiography (IOC) in the context of laparoscopic cholecystectomy focusing on various aspects related to both techniques. We made our search through PubMed, Web of Science, Cochrane Library, and Scopus, with the use of the following search strategy: ("laparoscopic ultrasonography" OR LUS OR "laparoscopic US" OR "laparoscopic ultrasound") AND ("laparoscopic cholecystectomy" OR LC). We incorporated diverse studies that addressed our topic, offering data on the identification of biliary anatomy and variations, the utilization of laparoscopic ultrasound in cholecystitis, the detection of common bile duct stones, and the criteria utilized to assess the accuracy of LUS. A total of 1526 articles were screened and only 20 were finally included. This systematic review assessed LUS and IOC techniques in cholecystectomy. IOC showed higher failure rates due to common duct catheterization challenges, while LUS had lower failure rates, often linked to factors like steatosis. Cost-effectiveness comparisons favored LUS over IOC, potentially saving patients money. LUS procedures were quicker due to real-time imaging, while IOC required more time and personnel. Bile duct injuries were discussed, highlighting LUS limitations in atypical anatomies. LUS aided in diagnosing crucial conditions, emphasizing its relevance post surgery. Surgeon experience significantly impacted outcomes, regardless of the technique. A previous study discussed that LUS's learning curve was steeper than IOC's, with proficient LUS users adjusting practices and using IOC selectively. Highlighting LUS's benefits and limitations in cholecystectomy, we stress its value in complex anatomical situations. LUS confirms no common bile duct stones, avoiding cannulation. LUS and IOC equally detect common bile duct stones and visualize the biliary tree. LUS offers safety, speed, cost-effectiveness, and unlimited use. Despite the associated expenses and learning curve, the enduring benefits of using advanced probes in LUS imaging suggest that it could surpass traditional IOC. The validation of this potential advancement relies heavily on incorporating modern probe studies. Our study could contribute to the medical literature by evaluating their clinical validity, safety, cost-effectiveness, learning curve, patient outcomes, technological advancements, and potential impact on guidelines and recommendations for clinical professionals.

The Role of Intraoperative Ultrasonography Associated with Clampless Technique in Three-Dimensional Retroperitoneoscopic Laparoscopic Enucleation of Completely Endophytic Renal Tumors

Objectives: To evaluate perioperative and functional outcomes of clampless laparoscopic tumor enucleation for completely endophytic renal tumors with the guide of intraoperative ultrasonography. Methods: We analyzed patients with clinically completely endophytic tumors, renal tumors, who underwent clampless three-dimensional (3D) retroperitoneoscopic laparoscopic tumor enucleation between January 2012 and January 2021. Patients with exophytic tumors were excluded. Intraoperative ultrasonography was used to map out the mass in all surgeries. Results: Overall, 57 patients underwent clampless 3D retroperitoneoscopic laparoscopic tumor enucleation. Mean surgical time was 131 minutes, and mean estimated blood loss was 202 mL. Mean hospital stay was 4.7 days. Major and minor postoperative complications occurred, respectively, in 3 and 10 cases. Only a patient had a positive surgical margin. One-year renal function did not differ from baseline. Conclusion: Our study showed that clampless laparoscopic enucleation guided by laparoscopic ultrasonography ensured satisfactory outcomes for completely intrarenal tumors, with excellent renal function preservation 1 year after surgery.

Laparoscopic ultrasonography-guided cryoablation of locally advanced pancreatic cancer: a preliminary report

OBJECTIVE

To evaluate safety and feasibility of laparoscopic ultrasonography (LUS)-guided cryoablation of locally advanced pancreatic cancer (LAPC).

PATIENTS AND METHODS

From April 2018 to December 2018, ten patients (five women, five men; mean age 58.2 ± 9.4 years) with LAPC underwent the operation. LUS was used to guide the cryoablation. Computed tomography (CT) imaging, biochemical analysis and pain score analysis by numeric rating scale (NRS) were used to assess treatment outcomes at 1 week and 3 months after the operation.

RESULTS

Cryoablation was performed by the operation in all cases. Seven patients received complete ablation and the success rate of operation was 70%. Two cryoablation cycles and an average of 1.4 ± 0.5 cryoprobes were used. The average freezing time and operation time were 23.8 ± 1.0 and 110.5 ± 24.7 min, respectively. The mean blood loss was 52.0 ± 16.6 ml. No major complications were observed after the operation. The mean maximum tumor diameter determined by CT decreased from 4.9 ± 0.7 cm before the operation to 4.7 ± 1.0 cm at 1 week and 4.6 ± 1.3 cm at 3 months, with P values of 0.53 and 0.51 (relative to the preoperative values), respectively. Postoperative CT imaging results suggested tumor necrosis in cryoablation-treated areas. The mean CA19-9 levels decreased from 347.5 ± 345.7 U/mL before operation to 190.4 ± 153.8 U/mL at 1 week and 182.7 ± 165.6 U/mL at 3 months, with P values of 0.15 and 0.14 (relative to the preoperative values), respectively. The average pain scores declined from 6.9 ± 1.1 before operation to 1.3 ± 1.2 at 1 week and 2.0 ± 0.8 at 3 months, with both P values of < 0.01 (relative to the preoperative values).

CONCLUSION

This preliminary study suggested that LUS-assisted cryoablation was a safe and feasible treatment for LAPC.

Intraoperative ultrasound: technique and clinical experience in robotic-assisted renal partial nephrectomy for endophytic renal tumors

OBJECTIVES

Surgical removal of completely endophytic renal tumors has presented great technical difficulties for surgeons. In this study, we aim to introduce the role and use of intraoperative ultrasound (IOUS) performed in robotic-assisted renal partial nephrectomy (RAPN) for endophytic renal tumors.

METHODS

We retrospectively assessed the demographics data and surgical outcomes of 58 consecutive endophytic renal tumor patients who were all attributed 3 points for the 'E' domain of the RENAL nephrometry score or 3 points for the exophytic rate of the PADUA score between October 2016 and September 2018. 38 patients who had undergone RAPN with IOUS were grouped. RAPN was carried out in another 20 patients without IOUS and these 20 patients were also grouped.

RESULTS

Patients in IOUS-guided group had significantly lower estimated blood loss (P < 0.001), shorter warm ischemia time (P = 0.010) and improved MIC (Margin, ischemia, and complications) rate (P = 0.026) and Pentafecta achievement (P = 0.016) compared to non IOUS-guided group. In multivariate logistic regression analysis, RAPN with IOUS was an independent predictor of MIC achievement (odds ratio 3.595; confidence interval 1.023-12.633; P = 0.046). Surface-intermediate-base (SIB) margin score was lower for IOUS-guided group vs non IOUS-guided group (P = 0.029).

CONCLUSION

RAPN for completely endophytic renal tumors is a feasible procedure in terms of complication rates, oncologic and functional outcomes. A robotic ultrasound probe operated by console surgeon generates a favorable perioperative outcomes and surgical margin rates after RAPN.

Role of intraoperative ultrasound in robotic-assisted radical nephrectomy with inferior vena cava thrombectomy in renal cell carcinoma

PURPOSE

To determine the impact of intraoperative ultrasound on robotic-assisted radical nephrectomy with inferior vena cava (IVC) tumor thrombectomy in renal cell carcinoma (RCC).

METHODS

We retrospectively analyzed intraoperative records of 27 patients with RCC and invasion of the IVC who underwent robotic-assisted nephrectomy with tumor thrombectomy at our center between December 2017 and July 2018. Diagnostic utility and impact of intraoperative transesophageal echocardiography (TEE), intraoperative robotic-assisted ultrasonography, and intraoperative contrast-enhanced ultrasound (CEUS) on surgical management were extracted from the surgical notes and intraoperative ultrasound reports.

RESULTS

Twenty-seven patients with thrombus had intraoperative ultrasound. Complete tumor removal was achieved in 22 patients, IVC transection in 5 patients, and no residual tumor was observed in all patients. Intraoperative TEE changed the robotic surgical strategy in three patients by monitoring thrombus-level regression. Downstaging of the thrombus level occurred in three patients: Levels IV to III in one and Levels III to II in two. Intraoperative robotic-assisted ultrasonography has facilitated safe VC clamp placement and identification and protection of collateral vessels during IVC transection in five patients. Intraoperative CEUS helped to differentiate the boundary between tumor thrombus (enhancement and small vessel pulsation) and bland thrombus (hypoechoic or no enhancement) in eight (29.6%) patients with bland thrombus.

CONCLUSIONS

Intraoperative ultrasound is a safe, minimally invasive technique that can provide accurate real-time information regarding the presence and extent of IVC involvement and guidance for placement of a vena cava clamp, confirming the character of the thrombus to plan an optimal surgical approach.

Contrast-enhanced ultrasound in detecting wall invasion and differentiating bland from tumor thrombus during robot-assisted inferior vena cava thrombectomy for renal cell carcinoma

Background

Vena cava thrombus is one of the main clinical manifestations of locally aggressive renal cell carcinoma (RCC). Inferior vena cava (IVC) wall invasion and presence of bland thrombus could affect the surgical outcome. This study aims to assess the value of contrast-enhanced ultrasound (CEUS) in detecting wall invasion and differentiating bland thrombus from tumor thrombus during robot-assisted IVC thrombectomy for RCC.

Methods

The intraoperative CEUS findings of 60 patients with RCC accompanied by IVC tumor thrombus were retrospectively analyzed. The CEUS features were compared with the intra- and post-operative pathological findings. CEUS in patients with wall invasion showed that the tumor thrombus was enhanced synchronously with the IVC wall, and the continuity of the IVC wall was lost. In contrast, in patients without wall invasion, CEUS showed that the contrast agent could pass between the tumor thrombus and the IVC wall, and the continuity of IVC wall was good. Typically, contrast-enhanced perfusion was seen in tumor thrombus but not in bland thrombus. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of CEUS were statistically analyzed.

Results

The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the typical enhancement mode of CEUS were 93.1, 93.5, 93.3, 93.1, and 93.5% in identifying wall invasion and 100, 96, 96.7, 83.3, and 100% in differentiating bland thrombus from tumor thrombus, respectively. There were excellent inter-observer agreements for identifying IVC wall invasion and differentiating bland thrombus from tumor thrombus with kappa coefficients of 0.90 and 0.97.

Conclusions

The present study indicates that intraoperative CEUS plays an important role in robot-assisted IVC thrombectomy for RCC. It can detect wall invasion and differentiate bland thrombus from tumor thrombus, thus offering real-time information to the operator during surgery.

Application of intraoperative ultrasonography in retroperitoneal laparoscopic partial nephrectomy: A single-center experience of recent 199 cases

Objectives:

To summarize the value and application experiences of intraoperative laparoscopic ultrasonography (ILUS) in retroperitoneal laparoscopic partial nephrectomy (RLPN).

Materials and Methods:

From January 2013 to December 2018, RLPN with ILUS was performed on the recent 199 patients in our center (two patients received bilateral RLPN due to suspected malignancy of both right and left sides), and the relevant clinical and follow-up data were retrospectively reviewed. Among them, 119 patients were male and 80 were female; the age of patients was 53.4 ± 12.3 years. Of all the renal tumors, 105 were located on the left side and 96 on the right side with a RENAL score of 6.6 ± 1.7. All the patients were diagnosed as or suspected of having a renal tumor by preoperative imaging examination. The ILUS was applied in all the operations to help locate the tumor, delineate the boundary, clarify the diagnosis, observe the blood supply, and so on.

Results:

RLPN with ILUS in these 199 patients was successfully performed without conversion to open surgery. All surgeries were completed in 90.2 ± 21.7 min, with 73.6 ± 89.2 mL for estimated blood loss, and 19.3 ± 5.6 min for warm ischemia time. The tumor size was 3.6 ± 1.5 cm, and all the surgical margins were negative. The drainage days and postoperative hospital days were 4.7 ± 2.3 and 6.1 ± 2.3, respectively. The preoperative creatinine was 69.7 ± 19.4 μmol/L compared with 61.6 ± 12.7 μmol/L measured 1 month postoperatively. There were 17 cases of renal cell carcinoma no more than 1 cm, and they were resected without artery clamp or a large amount of blood loss. Satellite tumors were confirmed in 12 cases, of which 8 were not detected by preoperative examinations and finally found by ILUS during surgeries.

Conclusion:

ILUS can alleviate the difficulty of preoperative diagnosis, facilitate surgical dissection, and improve the effect of nephron-sparing surgeries. Due to its great advantage, ILUS should further be promoted and applied.

Laparoscopic ultrasonography: The wave of the future in renal cell carcinoma?

Laparoscopic or robotic surgery is the main method of treating renal cell carcinoma (RCC). Laparoscopic surgery can accurately target lesions and shorten patient recovery time. Renal endogenous tumors or inferior vena cava tumor thrombi are very difficult to remove using the laparoscopic approach. The emergence of laparoscopic ultrasonography (LUS) has solved this problem. LUS can assist in the detection of tumor boundaries and the extent of tumor thrombi. The lack of tactile feedback may hinder the development of laparoscopic surgery for the treatment of renal cancer. LUS has become an important tool that has improved the rates of successful surgery. LUS is applied in not only early and locally advanced RCC treatment but also in monitoring ablation therapy, testing renal blood perfusion, and exposing renal pedicles. Sonographic techniques used for LUS include initial B-mode, Doppler, and contrast-enhanced ultrasound (CEUS). Contrast agents applied for CEUS do not induce nephrotoxicity and can display renal perfusion more accurately than the regular color Doppler ultrasound. According to current literature, LUS is a promising technique for the treatment of RCC, especially for endogenous RCC or RCC with thrombosis, and for monitoring the effectiveness of radiofrequency ablation, although further well-designed studies are warranted.

Investigation of Sacral Needle Depth in Minimally Invasive Sacrocolpopexy

PURPOSE

The aims of the study were to optimize surgical safety and to minimize vertebral disc puncture during sacral needle placement at the time of minimally invasive sacrocolpopexy. Cadaveric studies report that the anterior longitudinal ligament (ALL), which covers the vertebral disc and vertebrae, has a reported thickness of only 1.4 to 2.3 mm at L5-S1. Intervertebral disc puncture can accelerate disc degeneration, disc herniation, and loss of disc height, a risk that may be avoidable.

MATERIALS AND METHODS

After institutional review board approval, research consent was obtained from women undergoing primary laparoscopic sacrocolpopexy. Intraoperatively, sacral sutures were placed in the ALL with a 1.5 cm diameter CV-2 needle using Gore-Tex suture. Depth measurements were collected using a laparoscopic ultrasound transducer positioned on the sacral promontory (SP) between the 2 ends of the needle visible through the ALL. Two still-frame US images of the single needle were taken using the BK Medical software. Needle depth was calculated by measuring the distance from the top of the ALL to the needle.

RESULTS

Two satisfactory intraoperative images were obtained for all 9 participants. The mean needle depth at the SP was 3.96 mm. The interpatient needle depth varied from 2.07 to 9.04 mm.

CONCLUSIONS

In most participants (78%), the sacral needle depth exceeded 2.3 mm, suggesting that there may be risk to sacral suture placement without depth guidance at the promontory. During minimally invasive sacrocolpopexy, the depth of the ALL and the placement of the needle at the SP may result in inadvertent disc penetration. Surgeons should be conscious of the minimal depth of the ALL and consider placing the suture below the promontory to avoid the disc.

Laparoscopic marsupialisation of pelvic lymphoceles in different anatomic locations following radical prostatectomy

BACKGROUND

Pelvic lymphoceles (LCs) following radical prostatectomy (LC-RPs) are a well-described complication. Symptomatic LC-RPs are the most frequent, nonfunctional, postradical prostatectomy complications.

OBJECTIVES

Description of the clinical presentations of LC-RPs and the detailed technique of laparoscopic pelvic LC marsupialisation (LM), including perioperative results and follow-up.

DESIGN, SETTING, AND PARTICIPANTS

Data from 105 patients (age range: 57-76 yr) with symptomatic LC-RPs who underwent surgery in our institute were evaluated retrospectively. Pelvic ultrasound (US) and computed tomography scans, performed on all patients, revealed LC volumes ranging from 100 to 1200 ml. Fifty-five patients were refractory to prior percutaneous tube drainage and/or sclerotherapy. LM was performed using a three-trocar (n=60 patients) or two-trocar technique (n=45 patients).

SURGICAL PROCEDURE

With the patient in Trendelenburg position, LCs were accurately identified by inspection, compressibility, and/or laparoscopic needle aspiration. A Foley catheter was inserted. Through one or two working trocars in the left lower abdomen, an adequate peritoneal window (wide ellipse) was excised. The LC cavity was inspected and septae, membranes, and haematomas were removed.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Perioperative surgical outcomes, analgesic medication, and inflammation parameters were recorded. Follow-up and success rates were estimated with US for LC recurrence.

RESULTS AND LIMITATIONS

Five pelvic LC locations could be identified: paravesical, lateral pelvic (encapsulated and uncapsulated), prevesical, and with retroperitoneal extension. These were relevant for clinical diagnosis and management options. Pelvic LCs were right-sided in 37 patients, left-sided in 15, and on both sides in 53. All LM were uneventful and operating time (mean) ranged from 15 to 265 (31.7) min, which became shorter with increasing experience. One conversion with postoperative blood transfusion was necessary. Patients were discharged between 2 and 4 (mean: 2.3) d postoperatively. Postoperative US revealed primary success in all cases. Three patients developed recurrence from 1 to 3 wk posthospitalisation; otherwise, none had treatment for LC during a mean follow-up of 20 mo. Limitations include the retrospective study design and the small number of patients.

CONCLUSIONS

LC-RPs are common and can be classified into five different patterns of clinical/anatomic presentation. LM is simple, feasible, and safe as the first-line treatment for large, noninfected, symptomatic or refractory LC-RPs with fewer complications and an overall 97% success rate.

CT-guided percutaneous cryotherapy of renal masses

PURPOSE

To assess the results of initial and current techniques for percutaneous renal cryotherapy, including long-term imaging outcomes.

MATERIALS AND METHODS

Computed tomography (CT)-guided percutaneous cryotherapy was performed on 49 masses in 48 outpatients and procedure comfort noted for each. These 49 masses included 36 primary renal cell carcinomas (RCCs), 3 oncocytomas, 1 angiomyolipoma, 6 renal inflammatory lesions, 2 benign parenchymal changes, and 1 colon cancer metastasis. All complications were graded according to standardized criteria.

RESULTS

Patients received only local anesthesia and moderate sedation during the procedure and were discharged with minimal discomfort within 4-6 hours. All cryotherapy zones were well defined by CT during ablation as hypodense ice with an average diameter of 5.3 cm, covering an average tumor size of 3.3 cm. Average ablation zone diameters showed significant reduction over time (P < .001), becoming significantly less than the original tumor size by 12 months (P < .05). Major and minor complications were seen in 3 (6%) and 11 (22%) procedures, respectively. At a mean follow-up of 1.6 years (range, 1 week to 3.8 years) for primary RCC patients, four failures (11.1%) by imaging criteria were noted, but one proved to be inflammatory tissue at re-biopsy (estimated neoplastic failure rate = 3/36 = 8.3%).

CONCLUSIONS

Percutaneous renal cryotherapy is a well-tolerated outpatient procedure that allows safe, CT monitoring of ice formation beyond visible tumor margins. With appropriate cryoprobe placements, a low failure rate appears less dependent on tumor size or location. Ablation volume involution was >80% after 6 months.

Laparoscopic Doppler technology: applications in laparoscopic pyeloplasty and radical and partial nephrectomy

INTRODUCTION

The identification and isolation of vascular structures are crucial and technically demanding aspects of laparoscopic renal surgery. Doppler technology has been used for this purpose in laparoscopic varicocele repair, renal cryoablation, and adrenalectomy. However, it has not been formally described for use in laparoscopic radical nephrectomy, partial nephrectomy, or pyeloplasty. We report our initial experience with Doppler technology in 20 patients undergoing these procedures.

TECHNICAL CONSIDERATIONS

A laparoscopic Doppler probe was used in laparoscopic radical nephrectomy (n = 6), partial nephrectomy (n = 8), nephroureterectomy (n = 3), and robotic-assisted pyeloplasty (n = 3). The Doppler system consisted of a disposable 8-MHz probe passed through a 5-mm port and a battery-powered transceiver. The probe was used to guide dissection/isolation of the renal hilum and aberrant vasculature in radical and partial nephrectomy, confirm parenchymal ischemia before resection in partial nephrectomy, and identify crossing vessels during pyeloplasty. Nine accessory vessels were detected in 6 (35%) of 17 patients undergoing radical/partial nephrectomy or nephroureterectomy. In 1 case of partial nephrectomy, persistent parenchymal flow despite renal artery clamping required clamp repositioning. In 1 case of pyeloplasty, the Doppler probe detected a crossing vessel despite negative preoperative imaging findings. Use of the probe altered management in 7 (35%) and saved time in 15 (75%) of 20 cases. No complications were associated with the use of the probe.

CONCLUSIONS

Doppler ultrasound technology might have extended applications in laparoscopic renal surgery by facilitating the dissection and evaluation of vasculature. A prospective study with objective endpoints would be helpful in confirming the utility of this technology in these settings.

Intraoperative laparoscopic renal ultrasonography: Use in advanced laparoscopic renal surgery

OBJECTIVES

To highlight the use of intraoperative laparoscopic ultrasonography (ILUS) in complex renal surgery, as well its impact on management. ILUS has been used to facilitate advanced laparoscopic surgery, but only limited descriptions of the indications for its use have been published.

METHODS

All patients undergoing laparoscopic renal procedures requiring ILUS from October 2001 to March 2005 were reviewed. A total of 50 cases, including 35 partial nephrectomies, cryoablation of 6 renal tumors, 6 radical nephrectomies, 2 perinephric explorations, and 1 resection of a renal artery aneurysm were assessed by ILUS.

RESULTS

The average tumor size in the patients undergoing laparoscopic partial nephrectomy was 3.1 cm (range 1.4 to 8.0), and all margins were negative. Also, a previously unidentified satellite lesion was found in 1 patient. ILUS was essential in assessing iceball formation during laparoscopic renal cryotherapy. ILUS also proved useful in defining the anatomy during laparoscopic perinephric exploration, assessing renal vein thrombi during laparoscopic nephrectomy, and evaluating renal perfusion during laparoscopic renal artery aneurysm repair.

CONCLUSIONS

ILUS can be extremely useful in advanced laparoscopic renal surgery. In a number of situations, it is an essential surgical tool. With expanding indications for laparoscopic surgery, the indications for ILUS continue to grow.

Applications of intraoperative ultrasound in gynecological surgery

PURPOSE OF REVIEW

Gynecologists are well trained in office-based ultrasound, but are less experienced in the field of intraoperative ultrasound. Many gynecologic procedures may benefit from the use of real-time ultrasonography. The purpose of this review is to summarize the current use of intraoperative ultrasound in gynecologic procedures.

RECENT FINDINGS

Evaluation and assessment of the value of intraoperative ultrasound in gynecological procedures is essentially non-existent. The role of intraoperative ultrasound in gynecology is in its infancy, with anecdotal experience and literature involving predominantly case reports. Intraoperative ultrasound is helpful in laparoscopic myomectomy, particularly when the uterine contour is normal. It is also useful in defining pelvic anatomy in cases of complex reproductive procedures. Intraoperative ultrasound improves precision in characterizing ovarian lesions, particularly in the setting of endometriomas or dermoid cysts. It has been shown to decrease both operative time and complication rates in dilation and curettage procedures. Intraoperative ultrasound reduces recurrence and re-operation rates after hysteroscopy by facilitating more-complete resection of uterine myomas. Ultrasound guidance improves the efficiency of embryo transfer in in-vitro fertilization and could potentially be beneficial in other 'blind' gynecological procedures.

SUMMARY

Intraoperative ultrasound appears to be a safe and valuable tool for the gynecologic surgeon. Ultrasound improves visualization of anatomy, reduces complication and re-operation rates, and facilitates completion of more cases via less-invasive endoscopic approaches.

Real-time 3D laparoscopic ultrasonography

We have previously described 2D array ultrasound transducers operating up to 10 MHz for applications including real time 3D transthoracic imaging, real time volumetric intracardiac echocardiography (ICE), real time 3D intravascular ultrasound (IVUS) imaging, and real time 3D transesophageal echocardiography (TEE). We have recently built a pair of 2D array transducers for real time 3D laparoscopic ultrasonography (3D LUS). These transducers are intended to be placed down a trocar during minimally invasive surgery. The first is a forward viewing 5 MHz, 11 x 19 array with 198 operating elements. It was built on an 8 layer multilayer flex circuit. The interelement spacing is 0.20 mm yielding an aperture that is 2.2 mm x 3.8 mm. The O.D. of the completed transducer is 10.2 mm and includes a 2 mm tool port. The average measured center frequency is 4.5 MHz, and the -6 dB bandwidth ranges from 15% to 30%. The 50 omega insertion loss, including Gore MicroFlat cabling, is -81.2 dB. The second transducer is a 7 MHz, 36 x 36 array with 504 operating elements. It was built upon a 10 layer multilayer flex circuit. This transducer is in the forward viewing configuration and the interelement spacing is 0.18 mm. The total aperture size is 6.48 mm x 6.48 mm. The O.D. of the completed transducer is 11.4 mm. The average measured center frequency is 7.2 MHz, and the -6 dB bandwidth ranges from 18% to 33%. The 50 omega insertion loss is -79.5 dB, including Gore MicroFlat cable. Real-time in vivo 3D images of canine hearts have been made including an apical 4-chamber view from a substernal access with the first transducer to monitor cardiac function. In addition, we produced real time 3D rendered images of the right pulmonary veins from a right parastemal access with the second transducer, which would be valuable in the guidance of cardiac ablation catheters for treatment of atrial fibrillation.

Intraoperative ultrasound during a laparoscopic myomectomy

OBJECTIVE

To report a gynecologic use of a laparoscopic ultrasound transducer to isolate a myoma for surgical removal.

DESIGN

Case report.

SETTING

University-based infertility practice.

PATIENT(S)

A 44-year-old woman gravida 1 para 1 with history of a first trimester miscarriage who desired pregnancy as a participant in the donor egg program.

INTERVENTION(S)

Before she entered the assisted reproduction program, a patient was found to have a myoma that was greater than 2 cm with both intramural and submucosal components. During the laparoscopic evaluation, a laparoscopic ultrasound transducer helped identify and properly locate the myoma in what otherwise appeared to be a normal uterus. Appropriate laparoscopic hysterotomy incision was then made, thereby minimizing uterine trauma.

MAIN OUTCOME MEASURE(S)

Appropriately placed hysterotomy incision and successful reconstruction of uterus.

RESULT(S)

After the successful laparoscopic myomectomy, the patient achieved a pregnancy in our donor oocyte program.

CONCLUSION(S)

Laparoscopic intraoperative ultrasound can help gynecologic surgeons complete a laparoscopic myomectomy.

Early experience with laparoscopic cryoablation in patients with small renal tumors and severe comorbidities

PURPOSE

To present our preliminary experience with laparoscopic renal cryoablation in patients with small renal tumors and severe comorbidities.

PATIENTS AND METHODS

Eight patients with a mean age of 75.6 years (range 68-82 years) who had small (mean 2.6+/-0.7-cm; range 1.4-3.8-cm) peripheral renal cortical lesions and significant comorbidities underwent laparoscopic cryoablation with a 3-mm cryoprobe. None of the patients was considered a good candidate for extirpative surgery. Tumors were biopsied prior to cryoablation. Intraoperative laparoscopic ultrasonography was utilized to confirm the tumor and to monitor the biopsy and the cryoablation process.

RESULTS

Most patients had right-sided tumors, although there were no significant differences in the approach or outcome on this basis. Seven patients had intraoperative biopsies, and in all cases, good tissue samples were obtained. There were no intraoperative or postoperative complications. The average blood loss was 102.5+/-123.3 mL, and the mean operative time was 120+/-27.8 minutes. The mean hospital stay was 2.9+/-1.6 days. Postoperative imaging demonstrated defects consistent with ablation of the affected area; however, a residual nonenhancing mass defect usually was demonstrated.

CONCLUSION

Laparoscopic cryoablation appears to be safe for the treatment of solid or complex renal masses in elderly patients with severe comorbidities. Further studies are necessary to determine the long-term efficacy before this modality can be considered an acceptable curative treatment for small renal cortical tumors.

Functional reconstruction and minimally invasive techniques

Recent years have seen notable advances in imaging technologies. Three-dimensional computer-rendered techniques with rapid image acquisition have led to the development of virtual reality imaging. Virtual reality imaging allows interactive intraluminal navigation through any hollow viscus, simulating conventional endoscopy. This technique of virtual endoscopy has been applied to many organs, including the urinary tract. Virtual reality endoscopy is beginning to challenge the gold standard of conventional endoscopic evaluation. Recent advances in laparoscopic surgery are largely attributable to technological improvements in imaging equipment. Laparoscopic ultrasound has become a common adjunct in laparoscopic surgery. In particular, advances in video cameras and digital imaging technology have decreased the steep learning curve associated with laparoscopic procedures. Telerobotic systems offer several advantages to laparoscopic surgery, such as all six degrees of freedom, dexterity enhancement, tremor filtering, and stereovision. In addition, technological breakthroughs allow many procedures to evolve from open operations involving lengthy hospital stays to imaging-guided minimally invasive procedures performed on an outpatient basis. Finally, Internet-based imaging is changing the way in which urology services are delivered, by allowing rapid communication between remote locations.