Leonid Lobik

Laparoscopic laser soldering for repair of ureteropelvic junction obstruction in the porcine model.

BACKGROUND AND PURPOSE Laparoscopic pyeloplasty is used for the repair of ureteropelvic junction (UPJ) obstruction. Our objective was to introduce laser soldering to this procedure. MATERIALS AND METHODS We developed a system based on a CO2 laser, an infrared detector, and two infrared transmitting optical fibers to obtain temperature-controlled laser soldering of cuts in tissues. The system was used for laparoscopic soldering of incisions in the kidneys of pigs. RESULTS We carried out laparoscopic pyeloplasty successfully in a porcine model using fiberoptic laser soldering. Laparoscopic laser soldering was found to be faster than suturing. It was easier to use and provided watertight bonding. CONCLUSIONS This technique will be useful in pyeloplasty as well as other laparoscopic surgical procedures.

Cancer diagnostics using Fourier transform fiber optic infrared evanescent wave spectroscopy (FTIR-FEWS)

A Fourier transform IR spectrometer and IR transmitting AgClBr fibers were used for fiberoptic evanescent wave spectroscopy (FTIR-FEWS) of cancer. Malignant and healthy tissue samples were extracted from patients at the Meir Hospital in Israel, placed on a Silver Halide fiber, and measured using the FTIR-FEWS system. The IR spectra were analyzed and compared by taking the ratio of absorption of the active functional groups of Amide I at 1642 cm-1 and Amide II at 1545 cm-1. Clear differences appeared between the two types of tissue. When placing the tissue samples on bare fiber the reproducibility of the result was not satisfactory due to chemical interaction between the tissue and the fibers. This problem was solved by applying Polyethylene coating of thickness 1-2 μm on the fiber, leading to reproducible results. The results of these preliminary studies indicate that eh FTIR-FEWS technique can be used for cancer diagnostics. Combined with endoscopy this technique could be used to analyze tissues inside the body in vivo and in real time.

Lubricating Medical Devices with Fullerene-Like Nanoparticles

In the present work, MoS2 nanoparticles with fullerene-like structure, and most particularly those doped with minute amounts of rhenium atoms, are used as additive to medical gels in order to facilitate their entry into constricted openings of soft material rings. This procedure is used to mimic the entry of endoscopes to constricted openings of the human body, like urethra, etc. It is shown that the Re-doped nanoparticles reduce the traction force used to retrieve the metallic lead of the endoscope from the soft ring by a factor close to three times with respect to the original gel. The mechanism of the mitigation of both friction and adhesion forces in these systems by the nanoparticles is discussed.

Transrectal Ultrasonography-Guided Injection of Long-Acting Steroids in the Treatment of Recurrent/Resistant Anastomotic Stenosis After Radical Prostatectomy

BACKGROUND AND PURPOSE Different techniques have been used for the treatment of patients with anastomotic stenosis after radical prostatectomy (RP). In this retrospective study, we analyzed our experience with urethral dilation and consecutive transrectal ultrasonography (TRUS)-guided injections of long-acting steroids in the scar area. PATIENTS AND METHODS We reviewed the records of patients who underwent RP in our department from 2002 to 2010 and presented to the outpatient clinics with symptomatic anastomotic stenosis. Patients were treated with: Urethral dilation, cold knife (CK) urethrotomy, transurethral resection (TUR) of stenosis and dilation/resection of the strictures with consecutive TRUS-guided injection of a long-acting steroid (dilation+TRUS-steroids). Patients remained under follow-up, which included the assessment of voiding and continence patterns, as well as cystourethroscopy. RESULTS In 32 (10.8%) patients, symptomatic anastomotic stenosis was diagnosed. Initial urethral dilation succeeded in only 3 (10.3%) patients; thus, 29 remained with recurrent/resistant stenosis. Urethral dilation+TRUS-steroids was performed in 14 patients, while 8 patients underwent CK and in 7 TUR was performed. Patients in the dilation+TRUS-steroids group had lower re-treatment rates, and none of these patients became incontinent. Patients in the TUR group needed no re-treatment; however, they had the highest incontinence rate (57.1%). As a result, the highest efficiency quotient was in the dilation+TRUS-steroids with the lowest in the TUR group. CONCLUSION Urethral dilation with consecutive TRUS-guided injections of steroids has the highest efficiency quotient and can be performed under local anesthesia with a low risk of incontinence.

Clot retention and spontaneous rupture with secondary pneumatosis of bladder wall following routine cystoscopy.

In this article we report an unusual case of spontaneous rupture of bladder wall following office-cystoscopy. It took place in a patient who suffered from low-stage highgrade carcinoma of bladder with the different aggressive behavior. Finally, he underwent radical cystectomy, which showed micropapillary carcinoma and pneumatosis within the bladder wall. The cause of the latter finding is rather puzzling and has been never reported previously.

Radical cystectomy with W-shaped orthotopic ileal neobladder constructed with non-absorbable titanium staples-long term follow-up

PURPOSES We retrospectively assessed our experience with the W-shaped orthotopic ileal pouch, which was constructed with non-absorbable titanium staples. For these purpose, we discuss the results of bladder capacity, urinary continence and early and long-term postoperative complications. MATERIALS AND METHODS We included in the study 17 patients who underwent radical cystoprostatectomy followed by construction of an orthotopic W-shaped ileal pouch between October 2000 and November 2009. A 65-70 cm segment of ileum was isolated and prearranged into a W-configuration, leaving two 10 cm intact segments on both sides of the ileal fragment. In our technique we entirely anatomized all adjacent limbs in order to create a sphere-shaped pouch. The ureters were directly anastomized to both intact segments of the ileal division. All our patients underwent pouchscopy 6 months after operation and annually. RESULTS Mean operative time for neobladder reconstruction and ureteral anastomoses was 87 ± 7.67 minutes. In one patient a leak from the ileo-ileal anastomosis was confirmed on the 3rd day after operation. In 2 cases unilateral stricture of the ureteral-neobladder anastomosis was documented. Staple lines were mostly covered with ileal mucosa after 6 months. The mean functional bladder capacity was 340 ± 27.6 mL and 375 ± 43.4 mL at 6 and 12 months, respectively. First-year daytime and nighttime continence was good and acceptable in 90% and 78% of patients, while it increased to 95% during the 2nd year. CONCLUSIONS The long term follow-up shows that non-absorbable titanium staples can be safely used for creation of an orthotopic ileal neobladder. However, these data should be further validated in a larger series of patients.

Bladder welding in rats using a controlled-temperature CO2 laser system

The promising clinical potential for laser welding of tissues has generated a growing interest in this field. As improved laser welding system was constructed in this work. It was based on IR transmitting AgClBr fibers for laser power delivery and for temperature control. The fiberoptic system was used to transmit CO2 laser power for tissue heating and for non contact (radiometric) temperature monitoring and control. Bladder opening (cystotomy) was performed in 38 rats and 33 of the animals underwent laser welding. In 5 rats (control group) the bladder wound was closed with one layer continuous 6-0 dexon sutures. The rats were sacrificed on days 2, 10 and 30 for histological study. The temperature control of the upper tissue surface was set at 70 plus or minus 5 degrees Celsius. Bladder closure using laser welding was successful in 31/33 (94%) of the animals. The quality of the weld was examined immediately after the operation, revealing a water tight closure of the bladder wall. The histological examination showed an excellent welding and healing of the tissue. These results demonstrate the potential of temperature controlled CO2 laser welding.

Laser soldering for laparoscopic bonding of tissues in pigs

Introduction: Laparoscopic pyeloplasty is used for the repair of uretero-pelvic junction (UPJ) obstructions. Our aim was to do it using laser tissue soldering. Materials and Methods: We developed a tissue bonding system based on a CO2 laser, a temperature detector and infrared transmitting optical fibers, to obtain temperature controlled laser soldering of incisions. The system was then adapted for laparoscopic soldering of ureters of pigs. Results: We successfully carried out laparoscopic pyeloplasty in a porcine model, using a procedure based on CO2 laser soldering. Conclusions: Laparoscopic laser soldering was found to be faster than suturing, it was easier to use and provided watertight bonding. This technique will be useful in other surgical procedures.