Microsurgery in liver research: end-to-side portocaval microanastomoses in dogfish

BACKGROUND

The use of an operating microscope in animal liver surgery has made it possible to obtain new experimental models. The goal of this prospective animal study is to present our experience with dogfish portocaval microanastomoses.

METHODS

Nineteen portocaval microanastomoses were performed in dogfish. The end-to-side anastomoses were accomplished using continuous 11-0 sutures. The diameter of the vessels and time required for the anastomoses were measured. A patency test and its outcome were also prospectively evaluated at the time of anastomoses and then 3 and 6 months after.

RESULTS

The mean vessel diameter was 2.5 ± 0.2mm. The mean anastomosis time was 14 ± 1.5 min. The anastomoses patency rate was 100% at the time of surgery. A postoperative control performed after 3 and 6 months showed a partial stenosis in three animals.

CONCLUSION

The dogfish appears to be a reliable experimental model in liver research. Moreover, this technique could be used for microsurgical training.

Endovenous laser treatment: is there a clinical difference between using a 1500 nm and a 980 nm diode laser? A multicenter randomised clinical trial

AIM

We compared the use of two different laser wavelengths in the treatment of great saphenous vein (GSV) reflux: the 1500 nm versus the 980 nm diode laser. We studied the occlusion rates and noted possible side-effects.

METHODS

In three centers 180 great saphenous veins were treated with endovenous laser ablation (EVLA). By random selection half of the patients were treated with a 980 nm laser and half with a 1500 nm laser. A Duplex scan was scheduled at one month and six months postoperatively. Ecchymosis was measured at one week using a calculated scale. In addition the need for analgesics, the induration around the treated vein and patient satisfaction rate were noted. At two weeks postoperatively a quality of life score (CIVIQ2) was obtained.

RESULTS

The complete occlusion rates at six months were not statistical significant different between both groups (95.5% for 980 nm and 93.1% for 1500 nm). Most of the non-occluded veins had a filiform internal lumen and did not show reflux. There was no significant difference in the postoperative appearance of ecchymosis (P=0.09). Patients treated with a 1500 laser had less induration around the treated vein (P=0.002), less need to take analgetics (1.8 days versus 2.9 days) and had a better postoperative quality of life (P=0.018). The patient satisfaction rate did not differ in the two groups.

CONCLUSION

Using a 1500 nm diode laser in the treatment of an incompetent GSV, compared to the use of a 980 nm laser, results in similar occlusion rates at six months, but somewhat less side-effects.

A model to estimate the outcome of prostate cancer photodynamic therapy with TOOKAD Soluble WST11

Interstitial photodynamic therapy is becoming an interesting modality to treat some early stage prostate cancers. A light-sensitive drug is injected to the patient and activated by light using optical fibres inserted inside the prostate. In this work, we were interested in the characterization of the light action model for the WST11 (Tookad® Soluble) drug. A retrospective analysis was performed on results from 28 patients enrolled in phase I and II trials with the WST11 drug. A drug dose of 4 mg/kg patient, dose light of 200 J cm(-1) and wavelength of 753 nm were used. Correlation between the illuminated volume and the obtained necrosis, measured at day 7 MR images, was clearly established. This result suggests that photodynamic therapy planning is possible based on this model.

ProstAtlas: a digital morphologic atlas of the prostate

Computer-aided medical interventions and medical robotics for prostate cancer have known an increasing interest and research activity. However before the routine deployment of these procedures in clinical practice becomes a reality, in vivo and in silico validations must be undertaken. In this study, we developed a digital morphologic atlas of the prostate. We were interested by the gland, the peripheral zone and the central gland. Starting from an image base collected from 30 selected patients, a mean shape and most important deformations for each structure were deduced using principal component analysis. The usefulness of this atlas was highlighted in two applications: image simulation and physical phantom design.

A non rigid registration and deformation algorithm for ultrasound & MR images to guide prostate cancer therapies

Multimodality image registration is a critical issue in image-guided cancer ablation techniques. Focal therapies of prostate cancer are usually monitored using ultrasound imaging, while the dose planning is performed on MRI. In this study, a new multimodality images registration and deformation method, based on the Thin Plate Splines -Rigid Point Matching (TPS-RPM) algorithm, is introduced. The Method combines non-rigid mapping and interpolation to deform the images. Preliminary results obtained on phantom and clinical images showed that the registration is accurate and robust against landmarks initialization.

Laser assisted septal cartilage reshaping (LASCR): A prospective study in 12 patients

BACKGROUND AND OBJECTIVES

Occurring in one-third of the population, nasal obstruction is the most common complaint in an average rhinologic practice. The etiology is usually a deviation of the nasal septum, although other conditions, such as turbinate hypertrophy, can also cause nasal obstruction. Our team has already demonstrated that laser assisted cartilage reshaping can be used effectively for the correction of ear protrusion. This study aims to evaluate laser assisted septal cartilage reshaping (LASCR) to treat septal deviation.

STUDY DESIGN

Between March 2009 and September 2009, 12 patients (8 males, 4 females-mean age: 23 years) underwent LASCR for treatment of septal deviation. The mean NOSE score was 11.6. Preoperative examination included rhinomanometry and nasal endoscopy to exclude inferior turbinate or adenoid hypertrophy. Both sides of the septum were irradiated using a 1,540 nm laser connected to a 4 mm spot handpiece with integrated cooling (fluence: 50 J/cm(2)). Contact cooling made the treatment tolerable, but topical anesthesia was still required. Immediately after the procedure, an internal splint was inserted into the nostril and kept for 7 days. The NOSE score was calculated at 1 week, 1 month, and 3 months post-procedure and a rhinomanometry was carried out at 3 months.

RESULTS

The entire procedure took an average of 20 minutes. For all procedures, there were no lesions of the septal mucosa. Three months post-op, mean NOSE score improved from 11.6 to 5.3. Rhinomanometry assesses an increase in airflow (+19%) and improvement to air inflow resistance (-16%), confirming a subjective improvement. In seven adults, the expected septal reshaping was achieved. In five adults, incomplete septum reshaping was observed. In three patients it was correlated to anatomical variations: a thick septum in two cases and a long septum in one case. In the remaining two patients, it was due to insufficient fluence. In these cases, insufficient local anesthesia did not allow us to finish the procedure and the patients received a fluence of 30 J/cm(2) only. Those patients were re-treated at 3 months at 50 J/cm(2) fluence and all achieved suitable reshaping.

CONCLUSION

LASCR is a safe and less morbid approach to surgical septoplasty. Since significant variability in the cartilaginous elements of the nose is the rule rather than the exception, some improvements in the technique are still required.

[Thirty years of laser-assisted microvascular anastomosis (LAMA): what are the clinical perspectives?]

INTRODUCTION

Since the first studies by Jain and Gorisch (1979), laser-assisted anastomoses have been steadily developed to a stage where clinical use is within reach. The laser-assisted vascular microanastomosis (LAMA) procedure is performed more quickly than conventional anastomosis, the surgically induced vessel damage is limited, and reduced bleeding after unclamping is observed.

MATERIAL AND METHODS

A Medline literature search, for the January 1979 to February 2010 period, was performed to review articles focusing on the LAMA technique.

RESULTS

The search yielded a total of 354 publications, of which 87 were relevant: 82 were animal series and five clinical studies. Microsurgical techniques and principal characteristics of LAMA in patients are the focus of the analysis. This study discusses the technological innovations and new orientations in laser welding.

CONCLUSION

The first two clinical series using the 1.9-μm diode laser appear promising. Technical innovation will most likely lead to greater ease of use of the laser handpiece in the operating room.

[Photodynamic therapy and prostate cancer]

PURPOSE

Photodynamic therapy (PDT) is an innovative therapeutic modality in urologic oncology.

MATERIAL AND METHODS

We reviewed the current literature on principles and modalities of PDT in prostatic oncology.

RESULTS

Focal therapy of prostate cancer is an application field of PDT. Clinical phase II studies are ongoing to determine PDT efficacy and safety in this indication. PDT as salvage treatment after prostatic radiotherapy has been tested. Carcinologic results were promising but important side effects were reported. Individual dosimetric planification is necessary to avoid this toxicity.

CONCLUSION

PDT first clinical experience for prostate cancer has showed its technical feasibility. Several research ways are currently in study to improve carcinologic efficacy and to limit potential side effects.

Continuous or fractionated photodynamic therapy? Comparison of three PDT schemes for ovarian peritoneal micrometastasis treatment in a rat model

OBJECTIVE

This experimental study aimed to compare three illumination schemes to optimize hexaminolaevulinate (HAL)-PDT in a rat tumor model with advanced ovarian cancer.

MATERIALS AND METHODS

Peritoneal carcinomatosis was induced by intraperitoneal 5×10(6)NuTu-19 cells injection in 60 female rats Fisher 344. Carcinomatosis was obtained 50 days post-tumor induction. Four hours post-intraperitoneal HAL (Photocure ASA, Oslo, Norway) injection, three different schemes of PDT were performed during 25 min on a 1cm(2) area. (A) Fractionated illumination (n=20) with an on-off cycle ("on": 2 min and "off": 1 min) at 30mW cm(-2) until a fluence of 30J cm(-2), (B) continuous illumination (n=20) at 30mW cm(-2) with a fluence of (45J cm(-2)C) continuous illumination (n=20) at 20mW cm(-2) with a fluence of 30J cm(-2). Laser light was generated using a 532nm KTP laser (Laser Quantum, Stockport, UK). Biopsies were taken 24h after treatment. Quantitative histology was performed. Necrosis value was determined: 0-no necrosis to 4-full necrosis. Depth of necrosis was then measured for each sample and correlated to Necrosis value.

RESULTS

HAL-PDT was efficient in producing necrosis irrespective of the scheme. Tumor destruction was superior with fractionated illumination compared to both continuous illumination schemes regarding to the depth of necrosis (213±113μm vs 154±133μm vs 171±155μm) (p<0.05) or to the full necrosis rate (50% vs 30% vs 10%) (p<0.0001).

CONCLUSION

Fractionated illumination during photodynamic therapy (PDT) was shown to improve tumor response. Fractionated illumination with short intervals should be considered for an effective PDT of advanced ovarian cancer.

[Blood flow assessment with magnetic resonance imaging after 1.9 μm diode laser assisted arterial micronastomoses]

INTRODUCTION

The most important factor for successful free-flap transfer and replantations is a well-executed anastomosis. The aim of this study is to assess blood flow after laser assisted arterial microanastomosis (LAMA) using a 1.9 μm diode laser.

MATERIALS AND METHODS

LAMA was performed on a series of 10 carotidis on Wistar rats. Two 10/0 stay sutures and a standard laser tissue welding technique (λ: 1.9 μm; power: 120mW) were used. Similarly, a series of 10 conventional arterial anastomosis were performed (CSMA). For the two groups, contralateral non-operated carotidis were used as control. A positioning sequence, an anatomical sequence, an angiographic sequence and a flow sequence were performed 1 day after operation and then after 1, 4 and 8 weeks.

RESULTS

The arterial patency rate was 100% at the time of surgery. The mean clamping time was 7.2 min in the LAMA group compared to 10.7 min in the CSMA group. In the angiographic sequence, there were no aneurysms in both groups for all observation periods. At postoperative day 1, the mean loss of blood flow at the level of anastomosis in the LAMA group was 6% compared with 14% in the CSMA group. After 1, 4 and 8 weeks, there was an unhooking of the blood flow in the CSMA group: the loss of blood flow was 23%, 27% and 31% respectively, compared with 10%, 12% and 13% in the LAMA group. Moreover, one case of thrombosis was observed in the CSMA group after 1 week.

CONCLUSION

The flow-MRI emphasizes that 1.9 μm diode laser assisted microvascular anastomosis appears to be a consistent and reliable technique. These results show that 1.9 μm diode laser assisted microvascular anastomosis has potential for further development in the near future.