Cheol Kyu Oh

Initial experience with 50 laparoendoscopic single site surgeries using a homemade, single port device at a single center.

PURPOSE We report our technique of and initial experience with 50 patients who underwent laparoendoscopic single site surgery using a homemade single port device at a single institution. MATERIALS AND METHODS Between December 2008 and August 2009 we performed 50 laparoendoscopic single site surgeries using the Alexis wound retractor, which was inserted at the umbilical incision. A homemade single port device was made by fixing a size 7 1/2 surgical glove to the retractor outer ring and securing the glove fingers to the end of 3 or 4 trocars with a tie and a rubber band. A prospective study was performed in 50 patients to evaluate outcomes. RESULTS Of 50 patients 34 underwent conventional laparoendoscopic single site surgery, including radical and simple nephrectomy, and cyst decortication in 8 each, nephroureterectomy in 3, partial nephrectomy and adrenalectomy in 2 each, and partial cystectomy, ureterectomy and ureterolithotomy in 1 each, while 16 underwent robotic laparoendoscopic single site surgery, including partial nephrectomy in 11, nephroureterectomy in 3, and simple and radical nephrectomy in 1 each. Mean patient age was 52 years, mean body mass index was 23.4 kg/m(2), mean operative time was 201 minutes and mean estimated blood loss was 201 ml. Four intraoperative complications occurred, including 2 bowel serosal tears, diaphragm partial tearing and conversion to open radical nephrectomy. One case of postoperative bleeding was managed by transfusion. Surgical margins were negative in the 13 patients who underwent partial nephrectomy. Mean hospital stay was 4.5 days (range 1 to 16). CONCLUSIONS Our homemade single port device is cost-effective, provides adequate range of motion and is more flexible in port placement for laparoendoscopic single site surgery than the current multichannel port.

Robot-assisted Laparoendoscopic Single-site Surgery: Partial Nephrectomy for Renal Malignancy

OBJECTIVES To describe our experience with robot-assisted laparoendoscopic single-site surgery (LESS) to perform partial nephrectomy and evaluate a hybrid homemade port system as an effective access technique. METHODS From December 2008 to September 2009, robot-assisted LESS to perform partial nephrectomy through a hybrid homemade port was performed to treat 14 cases of renal cell carcinoma. The data, including patient characteristics, operative records, complications, and pathologic results, were analyzed. RESULTS The mean tumor size was 3.2 cm, the mean ischemic time was 30 minutes, and the mean operative time was 233 minutes. We used the hybrid homemade port technique in 10 cases. All surgical margins after partial nephrectomy were negative for malignancy. No port-related complications were reported. Two cases required conversion to mini-incisional partial nephrectomy. CONCLUSIONS Robot-assisted LESS for performing partial nephrectomy using a hybrid homemade port system is a safe and feasible treatment technique. It provided access for meticulous suturing on the renal parenchyma using articulating robot arms and ready access to the surgical field for the assistant.

Laparoscopic Partial Nephrectomy Versus Robot-Assisted Laparoscopic Partial Nephrectomy

PURPOSE Laparoscopic partial nephrectomy (LPN) is an alternative treatment modality for small-sized renal tumors. Robot-assisted LPN (RLPN) has also been performed with an advantage in repairing the defect after a resection of the tumor. We compared the perioperative data of patients treated with LPN with patients who underwent RLPN. MATERIALS AND METHODS From September 2006 to April 2008, 26 patients were treated with LPN and 31 with RLPN. Three arms were used for RLPN; camera was inserted through the 12 mm umbilical trocar port. Laparoscopic Bulldog clamps were used for clamping the renal hilum. We retrospectively compared each group on tumor size, operative time, estimated blood loss, warm ischemic time, and hospital stay. RESULT Operative time of LPN was shorter than that of RLPN (p = 0.034). Tumor size, estimated blood loss, and hospital stay were not significantly different in each group. No case was converted to open surgery. One patient in the RLPN group, however, was converted to robot-assisted radical nephrectomy because of severe bleeding. CONCLUSION RLPN is safe and feasible for small-sized renal tumors. Warm ischemic time is within reasonable limits. Associated morbidity is also low.

Robotic palpation and mechanical property characterization for abnormal tissue localization

Palpation is an intuitive examination procedure in which the kinesthetic and tactile sensations of the physician are used. Although it has been widely used to detect and localize diseased tissues in many clinical fields, the procedure is subjective and dependent on the experience of the individual physician. Palpation results and biomechanics-based mechanical property characterization are possible solutions that can enable the acquisition of objective and quantitative information on abnormal tissue localization during diagnosis and surgery. This paper presents an integrated approach for robotic palpation combined with biomechanical soft tissue characterization. In particular, we propose a new palpation method that is inspired by the actual finger motions that occur during palpation procedures. To validate the proposed method, robotic palpation experiments on silicone soft tissue phantoms with embedded hard inclusions were performed and the force responses of the phantoms were measured using a robotic palpation system. Furthermore, we carried out a numerical analysis, simulating the experiments and estimating the objective and quantitative properties of the tissues. The results indicate that the proposed approach can differentiate diseased tissue from normal tissue and can characterize the mechanical information of diseased tissue, which means that this method can be applied as a means of abnormality localization to diagnose prostate cancers.

Robotics applied in laparoscopic kidney surgery: the Yonsei University experience of 127 cases.

OBJECTIVE We report our experience on 127 kidney surgeries with the da Vinci surgical system and show the feasibility of a robotics application in a variety of kidney surgeries by both a laparoscopically-trained and a laparoscopically-naïve surgeon. METHODS Clinical data of patients who underwent kidney surgery with the da Vinci surgical system from September 2006 to April 2009 were reviewed. Data acquired from medical records included patient demographics, operative time, estimated blood loss (EBL), incidence of intraoperative complication, duration of hospital stay, blood transfusion rate, oncological outcomes, and follow-up results. RESULT One-hundred twenty-seven kidney surgeries have been conducted with the da Vinci surgical system at our institution. Three urologists--1 with formal endourology training, 1 with laparoscopic experience, and 1 laparoscopically naïve--have used it for a variety of procedures involving the kidney. The cases include 65 partial nephrectomies (RPN), 38 radical nephrectomies (RRN), and 24 nephroureterectomies with bladder cuff (RNU). Results on operative time, EBL, incidence of intraoperative injury, duration of hospital stay, and blood transfusion rate are comparable with contemporary studies. CONCLUSIONS Robotics application in kidney surgery is a viable option for various procedures. Our experience shows it can be safely and effectively conducted by both laparoscopically-trained and laparoscopically-naïve surgeons once they are accustomed to the robotics system.

Initial Clinical Experience of Simultaneous Robot-Assisted Bilateral Partial Nephrectomy and Radical Prostatectomy

A 62-year-old male patient with prostate cancer and bilateral renal cell carcinoma underwent a simultaneous robot-assisted bilateral partial nephrectomy and radical prostatectomy. We describe our initial experience of combined operation with a port strategy allowing reuse of ports and surgical considerations because of prolonged pneumoperitoneum.

Clinical Experiences of Pheochromocytoma in Korea

Purpose We report herein 119 patients with pheochromocytoma at our institute over the last 23 years. Materials and Methods Between 1986 and 2009, 119 patients were diagnosed with pheochromocytoma at our institute. We reviewed the medical records of these patients. Results Of 119 patients, 45 were male and 74 were female, and mean age was 43.83 ± 13.49 years. Forty-three patients (36.1%) were diagnosed incidentally, and 8 patients (6.7%) were found to have familial pheochromocytoma. The mean dimension of the tumors was 5.89 ± 3.18 cm. 4 patients had bilateral tumors; three of these patients were found to have familial pheochromocytoma and 1 patient was diagnosed with malignant pheochromocytoma. A total of eight patients (6.7%) were found to have malignant pheochromocytoma. In 1 patient, metastasis to a lymph node was found at the time of diagnosis. Metastases were found at a mean of 49 ± 25.83 (6-75) months after surgery in the other seven patients. 6 patients died of malignant pheochromocytoma at a mean of 31 ± 28.71 months (1-81) after diagnosis, and the other 2 patients survived for 15 and 24 months, respectively. Conclusion Approximately 35% of patients with pheochromocytoma are diagnosed incidentally, and the number of detected cases is increasing. Although familial pheochromocytoma was found only in 6.7% of the patients, genetic testing should be considered in all patients, especially in patients with a family history, young age, or multifocal, bilateral, extra-adrenal, or malignant tumors. Given that malignant pheochromocytomas are frequently diagnosed during the follow-up period, long-term follow-up is necessary to confirm the absence of recurrence or metastasis.

Two-port robot-assisted vs standard robot-assisted laparoscopic partial nephrectomy: A matched-pair comparison

OBJECTIVE To compare the outcomes between 2-port robot-assisted partial nephrectomy (2-portRALPN) and standard robot-assisted laparoscopic partial nephrectomy (sRALPN). METHODS From May 2009 to February 2010, 35 2-portRALPN were done by a single surgeon in a university-based tertiary referral center. A cohort of 35 patients who underwent sRALPN from September 2006 to July 2009 was selected for retrospective comparison and matched for tumor complexity. All patients underwent partial nephrectomy (PN) using the daVinci surgical robotic platform (Intuitive Surgical, Sunnyvale, CA). In the 2-portRALPN, a homemade umbilical port and an infraumbilical assistant port were used, whereas standard laparoscopic port placement was used for sRALPN. The clinical, operative, pathologic, and follow-up information were collected. RESULTS The operative time (187.5 vs 171.7 minutes, P=.110), warm ischemia time (29.5 vs 28.8 minutes, P=.209), blood loss (257 vs 242.5 mL, P=.967), complication rate (17.1 vs 11.4%, P=.495), and transfusion rate (8.6 vs 2.9%, P=.303) were comparable in both groups. The pain scores on the first postoperative day (4.5 vs 3.9, P=.236) and on the day of discharge (2.3 vs 1.9, P=.433), in-hospital morphine requirement (130.5 vs 122.2 mg, P=.115), and length of hospital stay (4.2 vs 4.2 days, P=.875) were likewise similar in both groups. CONCLUSION This matched-pair study design comparing 2-portRALPN with sRALPN shows that the outcomes of both techniques are comparable. The 2-portRALPN technique is a viable option until a more advanced robotic platform specifically designed for laparoendoscopic single-site surgery is developed and a pure robot-assisted laparoendoscopic single site surgery PN can be safely performed.

Changes in the distribution of calbindin D28-k, parvalbumin, and calretinin in the hippocampus of the circling mouse.

The circling (cir) mouse strain, a murine model of deafness caused by a spontaneous mutation, exhibits characteristic behaviors of circling and hyperactivity. In an induced-noise paradigm, cir mice display a significant loss in their spatial orientation abilities, and this has been suggested to be due at least in part to changes in calcium homeostasis. Auditory information is transferred from the cochlear nucleus to the hippocampus, where it is processed to modulate motor and sensory activity. Such a pathway could be affected at the cellular level by alterations in neurotransmission, including alterations that involve Ca(2+). However, there have been no studies in a hearing deficit model examining the concomitant molecular alterations in the hippocampus. Thus, in the present study we used immunohistochemistry to compare the distribution of the calcium-binding proteins (CaBPs) calbindin D-28k, parvalbumin, and calretinin in the hippocampi of heterozygous (+/cir), homozygous (cir/cir), and wild-type (+/+) mice. The expression of the CaBPs in various hippocampal subfields appeared to be significantly lower in cir mice (+/- and -/-) than in +/+ mice. Such a decrease in CaBP expression in cir/cir mice would alter calcium homeostasis, which in turn could affect the connection of the tri-synaptic circuit of the hippocampus as well as the cortical region. A decrease in CaBPs and the probable resultant glutamate-mediated excitability could contribute to the functional changes that lead to the characteristic behavioral features of cir mice.

Learning curve for robot-assisted laparoscopic radical prostatectomy for pathologic t2 disease.

Purpose To investigate the learning curve for robot-assisted laparoscopic radical prostatectomy (RALP) for pathologic T2 disease, we examined differences in perioperative outcomes according to time period. Materials and Methods Between July 2005 and June 2008, a total of 307 consecutive patients underwent RALP for prostate cancer and 205 patients had pathologic T2 disease. Patients were grouped into 6-month time periods. We collected and examined the patients perioperative data including age, body mass index (BMI), prostate-specific antigen (PSA), operation time, estimated blood loss, and positive surgical margin. Results There were no significant differences among the groups in age (p=0.705), BMI (p=0.246), PSA (p=0.425), or prostate volume (p=0.380). Operation time (p<0.001) and estimated blood loss (p<0.001) decreased significantly with time. The positive surgical margin rate also showed a decreasing trend, but this was not significant (p=0.680). Conclusions Operation time and estimated blood loss had a steep learning curve during the early 24 cases and then stabilized. A positive surgical margin rate, however, did not have a significant learning curve, although the positive surgical margin decreased continuously.