LMTB. Vaporization and coagulation properties of the Biolitec Ceralas HPD W Laser compared to other laser systems for BPH treatment

Transcription

1 sn LASER- und MEDIZIN-TECHNOLOGIE GmbH, BERLIN LMTB Vaporization and coagulation properties of the Biolitec HPD980 Laser compared to other laser systems for BPH treatment November, 200<»

2 U-ramOptcc. Ccralas HPD980 Content slmtb 1 PURPOSE OF THE INVESTIGATION 2 DESIGN OF EXPERIMENTS 2.1 TEST SITES, TISSUE SAMPLES, AND EXPERIMENTS St:T-l 2.2 EVALUATION METHOD 3 RESULTS 3.1 HISIOLOGICAL IMAGES 3.2 VAPORIZATION SIZES AND COAGULATION MARGINS 4 SUMMARY 5 13 If.

3 l'eramoplei; ; C'erolas HFD^O *nlmtb 1 Purpose of the investigation [n the following investigation the vaporization and coagulalion features of a CeramOptec HPD980 IOOW laser system were compared to a Laserscope GreenLight PV* laser system. The system is an infrared diode laser (wavelength 980nm) whereas the GreenLight PV* system (a frequencydoubled Nd:YAG) emits green light (wavelength 532nm). The GreenLight PV*' system is a pulsed system (pulse repetition rate 10kHz, quasi-cw) which offers an adjustment of average power between 30 and SOW whereas the HPD980 offers a cw mode as well as a pulsed mode at same power levels up to IOOW in average. The chosen pulse parameters for continuous pulsing where set to O.I seconds on-time and O.Ol seconds off-lime. The aim of this investigation was to gather performance data that demonstrate that the HPD980 produces a vaporization defect in prostate tissue that is equivalent to that created by the GreenLight PV* system. The GreenLight PV* laser received FDA clearance in May 2001 with an indication for vaporizalion in the treatment of BPH. 2 Design of experiments 2.1 Test sites, tissue samples, and experimental set-up The experiments were performed at two different test sites HI Aachen and Munich. At the Institute of Pathology, University Hospital RWTH Aachen, Prof. A. VVellmann. MD, treated a human prostate (sample SI) and a prostate (sample S2) with the HPD980 system. At the Laser Research Laboratory of the University Hospital Munich Großhadern, R. Sroka, PhD, treated a prostate (sample S4) both with the HPD980 system and with the GreenLight PV* system. The human prostate was taken at an autopsy carried out previously on the same day (73 year-old individual, no pathological findings) and frozen immediately after extraction. The prostates were also stored frozen at -18 C since extraction from the animals. All prostates were slowly adapted to room temperature shortly before the experiments took place. They \\ere cm axially in two halves which were fixated on cork plates (see fig. I). For treatment these set-ups \\ere placed in 35 "C tempered tab water. Fig. 1: Prosune tissue '-ample S4 fixated on a cork plate

4 CeramOpiei;. L'eralas HPD980 slmtb To simulate a B P H treatment, different cuts with both laser systems were made. For each laser system the appropriate type of fiber recommended by the particular manufacturer was utilized (CeramOptec: Sidefibre SF 980 DL; Laserscope: GreenLightPV ADDStat ). To generate representative results, the typical sweeping technique used for BPH laser ablation was applied. This means revolving the distal tip of the side-firing fiber for degrees while moving it back and forth over the treatment length. In all cases the total energy was applied to a zone of 14-22mm in length. The complete parameters of the experiments were tabulated in Table 1. Table I: Rxperimemal parameters test sampte tissue laser power mode energy length T1 S1 human Cera la s cw 2kJ 15mm T2 81 human cw 2kJ 15mm T3 81 human cw 10kJ 20mm T4 81 human pulsed 2kJ 15mm T5 31 human pulsed 6kJ 20mm T6 S2 cw 2kJ 15mm T7 S2 cw 2kJ 15mm TS S4 1QOW cw 3kJ 14mm T9 S2 cw 10kJ 20mm T10 S2 cw 10kJ 20mm T11 S2 pulsed 2kJ 15mm T12 S2 pulsed 6kJ 20mm T13 S2 pulsed 6kJ 20mm T14 S4 Green Light 80VV quasi-cw 2kJ 17mm T15 S4 GreenLight sow quasi-cw 6kJ 22mm

5 CenunOjHec. reralas HPD980 slmtb 2.2 Evaluation method After treatment the tissue samples treated in Aachen were cut into slices (perpendicular to the ablation notches) and afterwards placed in formalin. The samples treated in Munich were placed in formalin, transported to Aachen and then sliced in the same way. After a conventional liistological preparation and staining Prof. Wellmann assessed microscopically the size of vaporization and the coagulation depth for everv cut made. ^H" Fig. 2: Tissue sample S4 after the tests T14 and Tl.s i left) and after test T8 (righl). An additional lesl wilh the system and 6kJ energ\ amid mn be evaluated, because the relatively thin sample v as cut through.

6 CcramÜplCL:. Ccnilas HPD980 LMTB 3 Results 3.1 Histological images The following images are some typical examples of the histological slides that were evaluated by Prof. Wellmann at the Institute of Pathology, University Hospital RWTH Aachen. Fig. 3: icst!~1 (. uw). sample SI (human). Overview. See the coagulated glandular structures and the \ aporization notch (top right). Fig. 4: Test T3 (, cw), sample SI (human). See coagulation /<ine and v uporization (jeft).

7 l. erann )pi^ L'cralas HPD9SO ^i-mtb Fig. 5: Test T3 (, cw), saitiple SI (human). Coagulation zone in detail. Fig, 6: Test T4 (, pulsed), sample SI (human). Overview.

8 I <. a-iiniijpllx. (,'cralas HPD980 ^1 LMTB Fig. 7: 1 est T4 (. pulsed), sample SI (human). Detail, showing destructed, coagulated glandular structures v% Fig. 8: Test T5 (, pulsed), sample SI (human). Overview, showing, \aporization notch and coagulated glandular structures.

9 I CcranU'iptet:. Ccralas KPD980 LMTB ^ Fig. 9: Test P5 (, pulsed), sample SI (human). Detail. See miner hlurrcd connective, not fully coagulated (issue and vaporization (top right). f Fig. 10: Test T6 (, cvv), sample S2 (). Overview. Coagulation /one and vaporization (top right).

10 ( aai-nopiec. HPD980 ^LMTB Fig. II: Test T6 (. cw), sample S2 (). Detail. Gland \\iili u>agul;ilion artifacts (bottom right) and vaporization (top left). Fig. 12: Test T7 (, cw), sample S2 (). Overview. Vaporization (bottom! and coagulation zone with altered glandular structures.

11 CeramOptec, HPD980 ^LMTB Fig. 13: Test T8 ic'eralas, cw), sample S4 (). Vaporization notch and zone of coagulation Fig. 14: TesiTI I (, pulsed), sample S2 (). Vaporization notch and coagulated glandular structures. 10

12 CeramOptec, (.'cralas HPD980 slmtb Fig. 15: Test T12 (, pulsed), sample S2 (). Vaporization noich. Fig. 16: Test T13 < : pulsed), sample S2 (). Detail of coagulation zone. 11

13 i a.imoplcc. HPD980 slmtb Fig. 17; Tests T14 and T15 (GreenLight), sample S4 (). The central semi-lunar vaporization notch was generated by 2kJ (test TI4). The deep notch al ihe right border ol" the image was generated by 6kJ (test II?). 12

14 » cr.iml>pu.'c. HPD980 slmtb 3.2 Vaporization sizes and coagulation margins In the following charts the size of vaporization and the thickness of the coagulated margin are shown for all tests. These values were gained using laser parameters that arc typically applied with the two systems for the vaporization of BPH (cf. table t). In his evaluation Prof. Wellmann emphasized his observation, that there was no qualitative difference between the coagulation margins produced by the GreenLight system and the system, but only a quantitative one. This coagulation margin consists of necrotic tissue that will be catabolized and replaced by connective tissue. The first two charts (fig. 18 and 19) compare the results for the two different systems on prostate tissue. The next two charts (fig. 20 and 21) show the differences between lesions in human and tissue for the system only. Vaporization sizes, Cw,10KJ, 6,1..eiaias. pulsed, 6kJ: A ' 7. pulsed, ftttl 6kJ, 4.5 Fig. 18: Si/es of vaporization in the Icsis T6 - T15. all samples tissue. 13

15 I CeramOptec. CeraJas HPD980 ^LMTB Coagulation margins Cerafas. cw, Carolas, cw. 2kJ, 3,3 2kJ, 3,3, cw, 10kJ. 3,6 pulsed. 6KJ. 5.3 m m., pulsed, Csraias, pulsed, BkJ, 3.5 ZKJ.3.3 % Pig. 19: Sizes of coagulation margins in the tests T6 - T15, all samples cunine tissue. Comparison of and human samples - vaporization. 10kJ, cw ! ne. 2hJ. pulsed, fcJ, pulsed: 4.7 SKJ, Z '/ t \: i- % fy I \fa s f Fig. 20: Comparison of the vaporization sizes in human and samples, all tests jmade with the system. 14

16 CeramOptL'c. <_ crabs HPCW8Ü Comparison of and human samples - coagulation ^LMTB human, 6kJ. numsn. P" 1 «"* 4.8 human, 2kJ. pulsed; BU,l 4,4 I 1 1 Fig. 21: Comparison of the coagulation margins in human and samples, all tests made with the system. 15

17 J[iu.x. t L-talaslIPD980 ELMTB 4 Summary The two laser systems CeramOptec HPD980 and Laserscope GreenLight PV* were operated with the parameters recommended by the particular manufacturer fur the vaporization of prostate tissue. Using prostate tissue as target, the vaporization MZC of the system ( mm) was found to be on average approx. 2.5 times larger as produced hy the GreenLight system ( mm), regardless if the system was operated in the pulsed mode or in (he cw mode. Under these conditions the coagulated margin was approx. 3 times thicker for the system ( mm) than for the GreenLight system ( mm). The system was additionally applied to human prostate tissue. It was found, that the vaporization size as well as the coagulation margin in human tissue were approx. 1.3 l lines larger than in tissue. Trank P. Zgoda l Ml is Depi Medical Device Safety Berlin,