• 27 AUG 12
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    Dr. Mihai Florin Radulescu, Saarbrücken

    Dr.Ovidiu Ursu, Saarbrücken

     

    Material and Method

    HIFU(high intensity focused ultrasound ) is a highly  precise medical procedure using high-intensity focused ultrasound  to heat and destroy  pathogenic tissue rapidly. It is a minimal invasive or not invasive method to deposit acustic energy into tissue .

    Beetween september 2005 and  ianuary 2007 we  proceed 11 HIFU therapies . The indication  was  local failure after External Beam Radiation (9 Patients ), local reccurency after Radical Prostatectomy (2) . The general outcome was well tolerated from all this patients .One patient has a acute urinary obstruction and was temporary  thrugh a cystostomy treated .The average PSA follow up shows normality (< 0,2 ng/ml).

    Conclusion :HIFU is a promisive method for the tratement of  reccurencies after external beam radiation or radical prostatectomy .

     

    History

    The first investigations of HIFU for non invasive ablation were reported by Lynn et al in the early 1940s.Extesive important  early work was perfomed in the 1950s  and 1960s by William Fry and Francis Fry  at the University of Illinois  and  Carl Towsend , Howard White and George Gardner  at the Interscience  Research Institute of Champagne Ill. , culminated  in clinical treatments of neurogical disorders . In particular High Intensity ultrasound and ultrasound visualisation was accomplished stereotaxically with a Cincinatti precision  milling maschine to perform ablation of the brain tumors . Until recently  clnical trials of HIFU were few , perhaps due to the complexity of the treatments  and the difficulty of targeting the beam non invasively .With recent advances in medical imaging and ultrasound technology  the interes in HIFU ablation of tumors has increased.

     

    The first HIFU maschine was launched in Europe in 2001  after receving CE approuval , bringing a a first medical validation of the technology for localised prostate cancer . Comprehensive studies  by practicioners at more centers using the device have demonstrated clinical efficacity at more than 8 years with limited occurrence of side effects . Studies by Murat and collegues at Edurd Herrio Hospital in Lyon showed that fter treatment the progression –free survival rates are very high for low and intermediate risk patoents  with reccurent prostate cncer .

    HIFU tretement of prostate cancer is currently an approved therapy in Europe ; South Korea,Australia ,Japan . This year   HIFU  may be aproved by FDA  for prostate cancer ..

    Currently  over 9000 patients were treated worldwide.

     

    General principle of HIFU

    As an acoustic wave propagates through the tissue ,part of it is absorbed and converted to heat .With focused beams  , a very small focus can be achieved deep in tissues . When no enough , the tissue  is thermaly coagulated .At high enough acoustic intensities , cavitation (microbubbles forming and interacting with the ultrasound field ) can occur .During inertial cavitation ,very high temperatures  inside the bubbles occur , and the collaps is associated with a shock wave that can maechanichaly dammage tissue .

    The intensity at 30 Watts over 2000W/cm2 .This may produce heat of 80-100 grad C which destroy the tissue and kill the cancer .

    This technology can achieve precise “ ablation “ of diseased tissue  therefore called HIFU surgery.Because it detroys the dieseased tissue non-invsively  , it is also known  as “Non –invasive HIFU surgery”,:

     

    Aplication

    Uterine fibrosis

    Developpement of this therapy significantly broadened the range of treatement  options from uterine fibrosis.HIFU treatement for uterine fibrosii was approuved by the Food and  Drug Administration (FDA) in october 2004.

     

    Cancer

    HIFU has been succesfully applied in treatement of cancer to destroy solid tumors of the bone brain ,breast, liver ,pancreas,rectum,kidney,prostate .

    The earlest widespread use of HIFU ablation was as a treatement for prostate cancer .Developed and rafined ,this treatment is administrated trought a trans-rectal probe and relies on heat developed by focusing ultrasound wawes  into the prostate to kill the tumor .Promissing results have been reported in in large series of prostate cancer patients .These treatements are performed unter ultrasound imaging guidance , which allows  for tratement plannng and some minimal indication of the energy deposition .

     

    In international HIFU Centers  HIFU is used to ablate the entire prostate  gland using a transrectalprobe ..It is an out patient procedure  that usualy last1-3 hours. Results show it greatly reduces side effects common with other tretments for prostate cancer .

     

     

    Patient indication and selection

     

    The patients who benefit a HIFU therapy are the patients with T1-T2 prostate cancer (primary and recurrent after radical prostatectomy and radiation). The best results is confined to the group of patients with a PSA < 10 and Gleason  7 .

     

    The general exclusion criteria of the patients for HIFU are :

     

    • prostate larger than 40 gr  and a distance to the anterior rectal-wall > 4 cm(unless two treatments  to be scheduled –hormones)
    • patients with large intra-prostatic stones or calcifications (if they cause signficat shadowing)
    • patients with previous rectal wall surgery or hemorrhoids
    • patients with latex allergy reactions (probe sheat material is latex)

    System Overview

    Features of the Sonablate  500 PC include

    -small probe (at tip = 33 mm, at neck =17 m )

    -TRUS ( Transrectal Ultrasound Scanning and Therapy)= dual function piezo-electric transducer

    -real time imaging during  treatement .

    -3 D planning software with

    • reference images
    • numerous safety checks  as rectal wall monitoring = automatic temperature and distance control

    -simultaneus transversal and longitudinal imaging

    This sytem  called the “ Visualy Directed HIFU Concept  is a surgeon directed interactive situation-driven conrol and performance  of the procedure  by adjusting teatment parameters in real time through  a direct flexible control of energy and 2 D and 3D  Modus  for ad-hoc redefined treatment plan .

    Treatment

    The patient is in lithotomy position in general or spinal anestesia .

    The key steps of treatment are :

    Positioning

    Planning

    Therapy

     

    Positioning

    The rectal ultasounnd probe  shows and definethe anatomy of the prostate in tranversal and longitudinal views .

    Planning

    In this phase we Display the treatment zones from base to apex of the prostate .

    Treatment :

    We are treating the whole gland  agressively but carefully to avoid injury to the adjycent structures as the rectal wall , rhabdo-sphikter, ureters,neurovascularbundels, urethra.

     

    Studies

    Prof . Marberger  from University of Vienna treated  38 patients .

    The japanese Study data showed 97 % freedom from biochemical progression .

    (Prof .Uschida _ Tokio – folow up of 409 patients .

    British study  from the University College London

    (Prof. Marc Emberton )

    Our experience as a center of the European Multicenter – Study – upublished .

    N : patients , follow up  min 3  Month                          11

    PSA mean                                                                         8

    Continence                                                                    100 %

    1 cystoskopie to remove debris .

     

    Advantages over other techniques

    High Intensity Focused Ultrasound  is considered  a promising technology within the non invasive  or minimally invasive therapy segments  of medical technology  .HIFU `s capacity  to generate in-depth precise tissue necrosis using an external aplicator , with no effect on the surrounding structure is unique .

    Technology has continualy improved and additional  clinical applications , both diagnostic and therapeutic , have become an integral part of the new medecine today .

     

    References

    M.Emberton. The Institute of Urology , University College London- Abstract at the Britisch Association of Urological Surgeons 2006

    Uchida T , Clinical outcomes and quality of life after HIFU for localisated prostate cancer

    J.Urol 2004

    Uchida T etal  Jap Endourol  7 Year Folow –up . Oxford 2006

    FT. Murat . L Poissonier , Recurent Prostate Cancer after Radiotherapy –Salvage Treatment

    Terapia cu ultrasunete de inalta intensitate pentru cancerul de prostata

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