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Dive into the research topics where Christopher Tenggardjaja is active.

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Featured researches published by Christopher Tenggardjaja.


Journal of Endourology | 2010

Fluoroscopic Organ and Tissue-Specific Radiation Exposure by Sex and Body Mass Index During Ureteroscopy

Nathaniel Krupp; Ryan Bowman; Christopher Tenggardjaja; Forrest C. Jellison; Bryan Hill; Kamyar Ebrahimi; Jason C. Smith; Donald Farley; D. Duane Baldwin

INTRODUCTION Although radiation exposure from CT and plain film imaging has been characterized, the radiation received by patients during modern-era fluoroscopy has not been well described. The purposes of this study were to measure absolute organ and tissue-specific radiation doses during ureteroscopy and to determine the influence of body mass index (BMI) and sex on these doses. MATERIALS AND METHODS Eight cadavers underwent a simulated left ureteroscopy. Using a modern C-arm with automatic exposure control settings, thermoluminescent dosimeters were exposed for a fluoroscopy time of 145 seconds (mean time of clinical ureteroscopies from 2006 to 2008). Total tissue exposures were compared by BMI and between sexes using the Wilcoxon signed ranks test and the Mann-Whitney test with p < 0.05 considered significant. RESULTS Among all cadavers, radiation doses were significantly lower in all contralateral organs excluding the gonad (p < 0.012). Doses were similar bilaterally in the gonad in cadavers with BMI <30, and in all organs in cadavers with BMI >30 (p > 0.05). There were significantly higher mean bilateral gonadal doses in female cadavers (3.4 mGy left and 1.9 mGy right) compared with male cadavers (0.36 mGy left and 0.39 mGy right). The highest cancer risk increase was seen at the posterior skin equivalent to 104 additional cancers per 100,000 patients. CONCLUSION Contralateral doses were lower for all organs except the gonad when the BMI was <30. In contrast, when the BMI was >30, there was no difference in radiation dose delivered to the ipsilateral and contralateral organs. Gonadal doses were significantly higher in female cadavers. Modern-era fluoroscopy remains a significant source of radiation exposure and steps should be taken to minimize exposure during ureteroscopy.


Journal of Endourology | 2011

Robot-Assisted Radical Prostatectomy in Patients with Previous Renal Transplantation

Damien Smith; Forrest C. Jellison; Jonathan P. Heldt; Christopher Tenggardjaja; Ryan Bowman; Daniel H. Jin; Joshua Chamberlin; Paul D. Lui; D. Duane Baldwin

PURPOSE To evaluate the outcomes of robot-assisted radical prostatectomy (RARP) in patients with previous renal transplantation. PATIENTS AND METHODS We retrospectively identified all patients who had undergone RARP for localized prostate cancer between 2005 and 2008 at a single institution (N=228). Of these, three patients were renal transplant recipients. A four-arm robotic configuration was used in all patients. Port placement was modified in two of the three renal transplant recipients to avoid trauma to the renal allograft. Preoperative demographics, perioperative parameters, and postoperative outcomes were reviewed. RESULTS RARP was completed successfully in all three renal transplant recipients. As expected, the American Society of Anesthesiologists score (3.3 vs 2.4) and Charlson weighted index of comorbidity (4.7 vs 2.4) were greater in previous transplant patients. There were no major differences in mean age, Gleason score, body mass index, estimated blood loss, operative time, complications, or oncologic outcomes between the two groups. Each of the patients with renal allografts had an undetectable prostate-specific antigen level and was continent (needing no pads) at 13 months of follow-up. CONCLUSIONS RARP is feasible in patients with a previous renal transplant. Although technically more challenging, RARP can be performed in previous transplant patients with acceptable morbidity and oncologic outcomes similar to those of other prostate cancer patients.


Journal of Endourology | 2011

Hybrid Transureteral Natural Orifice Translumenal Endoscopic Nephrectomy: A Feasibility Study in the Porcine Model

D. Duane Baldwin; Christopher Tenggardjaja; Ryan Bowman; Kamyar Ebrahimi; Daniel S. Han; Daniel Greene; Paymohn Mahdavi; Walter Yuen; Joshua Chamberlin; Nathaniel Krupp

BACKGROUND AND PURPOSE Natural orifice approaches for nephrectomy have included access via the stomach, vagina, bladder, and rectum. The use of the ureter as a natural orifice for natural orifice translumenal endoscopic surgery (NOTES) nephrectomy has not been previously reported. The purpose of this study is to test the feasibility of transureteral laparoscopic NOTES nephrectomy. MATERIALS AND METHODS Three female farm pigs (29.2-30.8 kg) were placed into the lithotomy position. A cystoscopically placed extra-stiff guidewire was used to place a prototype dilating sheath into the left ureter. After dilation of the ureter and urethra, the sheath was exchanged for a 12-mm bariatric laparoscopic trocar. A 10.5-inch long 10-mm offset operating laparoscope with an internal 5-mm working port was used for the nephrectomy. One 2-mm and one 2/3-mm port were placed transabdominally to facilitate in situ morcellation. The kidney was cut into slices using the bipolar device and extracted via the ureteral port using the housing of a 12-mm bariatric stapling device. RESULTS All three transureteral nephrectomies were successfully completed. The total mean operative time was 220 minutes (range 113-346 min). Component portions of the procedure were: Ureteral access (mean 21 min), nephrectomy (mean 70 min), and kidney morcellation (mean 103 min). Mean estimated blood loss was 20 mL (range 5-50 mL). There were no intraoperative complications. CONCLUSIONS This nonsurvival porcine feasibility study demonstrates the successful performance of transureteral nephrectomy. This approach shows promise as a way to decrease the invasiveness of NOTES nephrectomy by using the ureteral orifice as an access site.


Journal of Endourology | 2011

A Prospective Randomized Comparison of Traditional Laparoendoscopic Single-Site Surgery with Needlescopic-Assisted Laparoscopic Nephrectomy in the Porcine Model

Lesli I. Nicolay; Ryan Bowman; Jonathan P. Heldt; Forrest C. Jellison; Neda Mehr; Christopher Tenggardjaja; William W. Millard; Jeffrey L. Koning; D. Duane Baldwin

BACKGROUND AND PURPOSE Laparoendoscopic single-site (LESS) surgery produces virtually no scar but is technically challenging because of the loss of triangulation. The objective of this study is to compare classic transumbilical LESS nephrectomy with needlescopic-assisted laparoscopy (NAL) surgery. In doing so, we evaluated whether the addition of a single 2-mm subcostal port could restore triangulation while not jeopardizing recovery or cosmetic outcome in the porcine model. MATERIALS AND METHODS Ten female farm pigs were randomized to laparoscopic nephrectomy with either LESS or NAL. In LESS, a TriPort was placed through a single 2.5-cm umbilical incision. In NAL, 5- and 10-mm ports were placed in the umbilicus and a 2-mm port was placed in the midclavicular line. Preoperative, perioperative, and postoperative parameters were compared. Variables were analyzed with the Wilcoxon signed-rank test and two-tailed Fisher exact test. Cosmesis was evaluated objectively using the Vancouver Scar Scale and subjectively by a blinded dermatologist. A cost analysis was performed. RESULTS Estimated blood loss was minimal in both groups (28.8 mL in LESS and 9.4 mL in NAL). Operative time was significantly shorter in NAL (103 vs 150 min; P<0.001). There was no difference in complications (2 vs 1; P=0.500), objective cosmesis (3.9 vs 3.8; P>0.2), or subjective cosmesis (2 vs 3; P=0.500). The NAL protocol had significantly lower disposable equipment costs (


Advances in Urology | 2011

Donor Smoking Negatively Affects Donor and Recipient Renal Function following Living Donor Nephrectomy.

Jonathan P. Heldt; Robert Torrey; Daniel Han; Pedro W. Baron; Christopher Tenggardjaja; Justin McLarty; Tekisha U. Lindler; D. Duane Baldwin

363 vs


Journal of Endourology | 2011

Patients with End-Stage Renal Disease Are Candidates for Robot-Assisted Laparoscopic Radical Prostatectomy

Jonathan P. Heldt; Forrest C. Jellison; Walter Yuen; Christopher Tenggardjaja; Paul D. Lui; Herbert C. Ruckle; Gary R. Barker; D. Duane Baldwin

1696). CONCLUSIONS The addition of a 2-mm subcostal port and the restoration of triangulation in the NAL protocol enable shorter operative times, increased surgeon comfort, improved technical ease, and lower costs while maintaining the scarless cosmesis of the traditional LESS protocol.


Journal of Endourology | 2010

Hemostatic Sandwich to Control Percutaneous Nephrolithotomy Tract Bleeding

William W. Millard; Forrest C. Jellison; Christopher Tenggardjaja; Kamyar Ebrahimi; D. Duane Baldwin

Background. While tobacco use by a renal transplant recipient has been shown to negatively affect graft and patient survival, the effect of smoking on the part of the kidney donor remains unknown. Methods. 29 smoking donors (SD) and their recipients (SD-R) as well as 71 non-smoking donors (ND) and their recipients (ND-R) were retrospectively reviewed. Preoperative demographics and perioperative variables including serum creatinine (Cr) and glomerular filtration rate (GFR) were calculated and stratified by amount of tobacco exposure in pack-years. Clinical outcomes were analyzed with a Students t-test, chi-square, and multiple linear regression analysis (α = 0.05). Results. At most recent followup, SD-Rs had a significantly smaller percent decrease in postoperative Cr than ND-Rs (−57% versus −81%; P = 0.015) and lower calculated GFRs (37.0 versus 53.0 mL/min per 1.73 m2; P < 0.001). SDs had a larger percent increase in Cr than NDs at most recent followup (57% versus 40%; P < 0.001), with active smokers having a larger increase than those who quit, although this difference was not statistically significant (68% versus 52%; P = 0.055). Conclusions. Use of tobacco by kidney donors is associated with decreased posttransplant renal function, although smoking cessation can improve outcomes. Kidneys from donors who smoke should be used with caution.


Transplantation | 2010

A Novel Bridging Hand-Assisted LESS Donor Nephrectomy Technique

Paymohn Mahdavi; Ryan Bowman; Christopher Tenggardjaja; Forrest C. Jellison; Kamyar Ebrahimi; D. Duane Baldwin

BACKGROUND AND PURPOSE Patients with end-stage renal disease (ESRD) have multiple comorbidities that place them at increased risk for surgical complications. Consequently, patients with both ESRD and prostate cancer (PCa) have rarely been considered candidates for radical prostatectomy. The objective of this study is to compare ESRD patients who are undergoing robot-assisted laparoscopic prostatectomy (RALP) with a cohort of patients with no history of dialysis. PATIENTS AND METHODS A retrospective review was conducted of 430 patients who were undergoing RALP, including 12 receiving dialysis at the time of surgery. Preoperative demographics, perioperative parameters, and postoperative outcomes were compared using a two-tailed Student t test and a chi-square test, with significance at P<0.05. RESULTS Patient demographics including body mass index, Gleason score, and prostate-specific antigen (PSA) value were similar between the two groups. Patients with ESRD had younger age (55.5 vs 62.9 years; P<0.01), higher American Society of Anesthesiologists scores (3.7 vs 2.5; P<0.01), and higher age-adjusted Charlson Comorbidity Index scores (6.2 vs 4.2; P<0.01). Patient outcomes including operative time, estimated blood loss, complication rate, postoperative stay, and positive margins did not differ significantly between groups. No ESRD patients needed pads or had a detectable PSA level using an ultrasensitive assay. CONCLUSIONS This series represents the largest series of patients with ESRD undergoing RALP. These patients experienced similar outcomes compared with patients with no history of dialysis despite greater preoperative comorbidity. RALP produces minimal fluid shifts, low blood loss, and excellent cancer control, making it an ideal treatment option to prepare patients with both ESRD and PCa for renal transplantation.


Archive | 2015

Open Transabdominal Sacrocolpopexy

Christopher Tenggardjaja; Sandip Vasavada

BACKGROUND AND PURPOSE Significant bleeding necessitating use of a tamponade balloon, embolization, or renal exploration is a rare but catastrophic complication after percutaneous nephrolithotomy (PCNL). The purpose of this study is to review the success of a novel, minimally invasive technique for controlling percutaneous tract bleeding that is refractory to conventional measures. MATERIALS AND METHODS A retrospective review was performed on four patients with refractory tract hemorrhage that was managed with a novel gelatin matrix hemostatic sandwich technique. In this technique, a 5F angiographic reentry catheter was placed through the kidney into the bladder and a 22F Councill-tip catheter balloon was passed over this catheter and positioned so that the inflated balloon would occlude the inner surface of the nephrostomy tract. Next, a 16F Councill-tip catheter was placed over a second wire so that the uninflated balloon was just underneath the skin surface. Gelatin matrix hemostatic sealant was then injected to fill the tract. Inflation of the outer balloon completely sealed the tract, completing the hemostatic sandwich. RESULTS This technique was successfully applied to four patients with tract bleeding that would not stop with pressure or a conventional nephrostomy tube alone. The average estimated blood loss was 562 mL, and three of four patients avoided transfusion. All postoperative hemoglobin values stabilized within 2 days of surgery. There were no major or minor complications after use of this technique. No patients needed angioembolization or renal exploration. CONCLUSIONS This novel hemostatic sandwich technique should be considered as an option for the control of refractory tract hemorrhage after PCNL.


Current Urology Reports | 2013

Advances in minimally invasive repair of vesicovaginal fistulas.

Christopher Tenggardjaja; Howard B. Goldman

Abstract Objectives: To address the significant shortage of kidneys available for transplant, laparoendoscopic single-site surgery (LESS) has been employed to further decrease the morbidity of kidney donation. To circumvent the complexity of LESS, we have developed a bridging hand-assisted LESS (BLESS) technique that allows the surgeon to gain experience with single-incision surgical techniques in the setting of traditional hand-assisted laparoscopy. Methods: A retrospective study of three patients undergoing BLESS donor nephrectomy was performed. Similar to LESS, this bridging technique employs a single periumbilical incision, but enlargement of the incision by a few centimeters facilitates immediate transition to hand-assisted laparoscopy if needed. Statistics on preoperative, perioperative, and postoperative variables was collected for the patients undergoing this procedure. Results: BLESS patients had a mean age of 31. Average postoperative hospital stay was short at 1.34 days, with two of the three p...

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D. Duane Baldwin

Loma Linda University Medical Center

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Ryan Bowman

Loma Linda University Medical Center

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Forrest C. Jellison

Loma Linda University Medical Center

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Jonathan P. Heldt

Loma Linda University Medical Center

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Ashley King

Virginia Commonwealth University

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