Technical Feasibility of Transperineal MR-Guided Prostate Interventions in a Low-Field Open MRI Unit: Canine Study

Lakosi, Ferenc; Antal, Gergely; Vandulek, Csaba; Kov́acs, Árṕad; Garamvölgyi, Rita; Petneházy, Örs; Bajzik, Gábor; Hadjiev, Janaki; Romics, Imre; Bogner, Péter

doi:10.1007/s12253-008-9111-3

Cited by 6 publications

(8 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The reported mean errors of coaxial needle placements during transperineal MR-guided biopsy [14,17] ranged from 2.1 to 6.93 mm. In our previous canine study the average needle accuracy of 37 insertions experienced was 2.9 mm, with the maximum error of 4.5 mm [21]. In the human study we could adequately reproduce these results (mean: 2.9 mm, maximum error: 5 mm) with the exception that we chose to analyze the plastic catheter tip deviations, instead of metallic ones for three main reasons.…”

Section: Discussionmentioning

confidence: 93%

“…In the frame of our MR-guided prostate intervention program we have initiated a three phases -gel phantom, cadaver and healthy caninestudy to develop a methodology for MR-guided high-doserate (HDR) prostate BT focusing on image quality [21]. The excellent preliminary results facilitated us to introduce this method into the clinical practice.…”

Section: Hdrmentioning

confidence: 99%

“…1a,b. Details of the positioning, device description and template reconstruction have been previously described in a developmental canine study [21]. In brief, for the interventional procedures, an MR compatible device was designed consisting of a template-obturator rod (TOR) (Fig.…”

Section: Positioning Device Descriptionmentioning

confidence: 99%

See 2 more Smart Citations

Open MR-Guided High-Dose-Rate (HDR) Prostate Brachytherapy: Feasibility and Initial Experiences Open MR-Guided High-Dose-Rate (HDR) Prostate Brachytherapy

Lakosi

Antal

Vandulek

et al. 2011

Pathol. Oncol. Res.

Self Cite

View full text Add to dashboard Cite

The aim of our pilot study was to demonstrate the feasibility and dosimetric quality of MR-guided HDR prostate brachytherapy in a low-field 0.35T open MRI scanner and to present our initial clinical experiences. 16 patients with intermediate- to high-risk localized prostate cancer were treated with 46-60 Gy of external beam radiotherapy preceded and/or followed by an 8 Gy MR-guided HDR boost. For interventions an MR compatible custom-made system, coaxial needles and plastic catheters were used. Template reconstruction, trajectory planning, image guidance, contouring and treatment planning were exclusively based on MR images. For treatment planning, dose-point- and anatomy-based inverse planning optimization was used. Image quality was found to be good to excellent in almost all cases. The mean catheter placement accuracy modeled by Rayleigh distribution was 2.9 mm with a sigma value of 2.3 mm. The mean and standard deviation (SD) of the dosimetric results for the target volume were the following: V100: 94.2 ± 4.3%, V150: 43.9 ± 6.8%, V200: 18.5 ± 5.9%. The mean D(0.1), D(1) and D1 values for the intraprostatic urethra were 117.6 ± 12.5%, 98.5 ± 19.9% and 122.3 ± 16.4%, respectively. Regarding the rectal wall the mean D(0.1), D(1) and D(2) values were 77.3 ± 7.2%, 64.8 ± 7.5%, and 53.2 ± 9.1%, respectively. The mean maximum dose for the inner rectal surface was 53.5 ± 9.2%. No RTOG Grade 3 or worse acute toxicities were observed. Our method seems to be a promising approach for performing feasible, accurate and high-quality MR-guided HDR prostate brachytherapy. To determine the long term side effects and outcome higher number of patients, additional follow-up is needed.

show abstract

Section: Discussionmentioning

confidence: 93%

Section: Hdrmentioning

confidence: 99%

See 1 more Smart Citation

Open MR-Guided High-Dose-Rate (HDR) Prostate Brachytherapy: Feasibility and Initial Experiences Open MR-Guided High-Dose-Rate (HDR) Prostate Brachytherapy

Lakosi

Antal

Vandulek

et al. 2011

Pathol. Oncol. Res.

Self Cite

View full text Add to dashboard Cite

show abstract

“…In prostate BT, it is usually accepted that the target volume is the whole prostate, but with respect to the homogeneity of the dose distribution there are significant differences in the literature [28]. Several implantation techniques exist according to the number and placement of needles [3,7,11,12,21,[29][30][31]. By placing a few needles peripherally, the dose is larger in the peripheral zone, while distributing more needles uniformly the whole prostate can be irradiated more homogeneously.…”

Section: Discussionmentioning

confidence: 99%

The Effect of Needle Number on the Quality of High-dose-rate Prostate Brachytherapy Implants

Fröhlich

Ágoston

Lövey

et al. 2010

Pathol. Oncol. Res.

View full text Add to dashboard Cite

The aim of this study is to evaluate the effect of the number of needles on the quality of dose distributions in high-dose-rate (HDR) prostate implants regarding target coverage, dose homogeneity and dose to organs at risk. Treatment plans of 174 implants were evaluated using cumulative dose-volume histograms. The plans were divided into three groups according to the number of implanted needles: <15: LNG (low number group), 15-17: MNG (medium number group) and >17: HNG (high number group). Treatment planning was based on transrectal ultrasound imaging. Dose-volume parameters for target (V90, V100, V150, V200, D90, D(min)) and quality indices (DNR, DHI, CI, COIN) were calculated. Maximal dose in reference points and high dose volumes were determined for rectum and urethra. Nonparametric analysis of variance and correlation was used with regard to needle numbers. Between the groups differences were found only in the following parameters: V(p) was larger when more needles were used with the values of 22.8 cm(3), 28.0 cm(3) and 30.9 cm(3) for the three groups, and more needles were used when the central cross-section of the prostate was larger. V200 in MNG was lower than in LNG (12%, 14%). Dose to rectum was higher in MNG than in LNG (D(2): 51%, 47%). Doses to the urethra were higher in HNG than in MNG (D1: 142%, 137%, and D(0.1): 128%, 125%). There was no significant difference in other parameters. Different number of needles results significant differences in treatment plans. However, the optimal needle number depends on not only the size of the prostate, but also the individual anatomy of the patient. Based on our results, in most cases the use of 15-17 needles seems to provide a dosimetrically acceptable treatment plan in HDR prostate implants.

show abstract

“…Compared to US, MRI provides excellent visualization of the prostate gland with its substructures, focal lesions within the gland, and surrounding periprostatic tissues, and is widely believed to be the ideal modality for imaging prostate cancer (Beyersdorff et al 2002). In the recent years, researchers have been investigating the clinical utility of MRI for targeted biopsy by fusing the preprocedurally acquired MRI with the intra-procedural US (Ukimura et al 2010, Natarajan et al 2011) or by means of intraoperative MRI for needle and anatomy visualization (Cormack et al 2000, D’Amico et al 2000, Hata et al 2001, Beyersdorff et al 2002, Susil et al 2003, Susil et al 2004, Menard et al 2004, Krieger et al 2005, Zangos et al 2005, Susil et al 2006, Engelhard et al 2006, Blumenfeld et al 2007, de Oliveira et al 2008, Hambrock et al 2008, Rea et al 2008, Lakosi et al 2009, Oguro et al 2009, Menard et al 2010, Menard et al 2011, Yakar et al 2011, Zangos et al 2011, Schouten et al 2012). While US-guided biopsy has been emerging because of its availability, portability, and the recent progress in imaging quality of US, MRI-guided biopsy has the advantages of better soft tissue contrast and applicability to patients who cannot undergo TRUS-guided biopsy due to previous total colectomy.…”

Section: Introductionmentioning

confidence: 99%

In-bore setup and software for 3T MRI-guided transperineal prostate biopsy

Tokuda¹,

Tuncalı²,

Iordachita³

et al. 2012

Phys. Med. Biol.

View full text Add to dashboard Cite

MRI-guided prostate biopsy in conventional closed-bore scanners requires transferring the patient outside the bore during needle insertion due to the constrained in-bore space, causing a safety hazard and limiting image feedback. To address this issue, we present our custom-made in-bore setup and software to support MRI-guided transperineal prostate biopsy in a wide-bore 3 Tesla (T) MRI scanner. The setup consists of a specially designed tabletop and a needle-guiding template with Z-frame that give a physician access to the perineum of the patient at the imaging position and allow performance of MRI-guided transperineal biopsy without moving the patient out of the scanner. The software and Z-frame allow registration of the template, target planning, and biopsy guidance. Initially, we performed phantom experiments to assess the accuracy of template registration and needle placement in a controlled environment. Subsequently, we embarked on our clinical trial (N = 10). The phantom experiments showed that the translational errors of the template registration along the right-left (RP) and anterior-posterior (AP) axes were 1.1 ± 0.8 mm and 1.4 ± 1.1 mm respectively, while the rotational errors around the RL, AP, and superior-inferior axes were 0.8 ± 1.0 degrees, 1.7 ± 1.6 degrees, and 0.0 ± 0.0 degrees respectively. The 2D root-mean-square (RMS) needle placement error was 3.0 mm. The clinical biopsy procedures were safely carried out in all ten clinical cases with a needle placement error of 5.4 mm (2D RMS). In conclusion, transperineal prostate biopsy in a wide-bore 3T scanner is feasible using our custom-made tabletop set up and software, which supports manual needle placement without moving the patient out of the magnet.

show abstract

Technical Feasibility of Transperineal MR-Guided Prostate Interventions in a Low-Field Open MRI Unit: Canine Study

Cited by 6 publications

References 21 publications

Open MR-Guided High-Dose-Rate (HDR) Prostate Brachytherapy: Feasibility and Initial Experiences Open MR-Guided High-Dose-Rate (HDR) Prostate Brachytherapy

Open MR-Guided High-Dose-Rate (HDR) Prostate Brachytherapy: Feasibility and Initial Experiences Open MR-Guided High-Dose-Rate (HDR) Prostate Brachytherapy

The Effect of Needle Number on the Quality of High-dose-rate Prostate Brachytherapy Implants

In-bore setup and software for 3T MRI-guided transperineal prostate biopsy

Contact Info

Product

Resources

About