In vitro evaluation of the safety and efficacy of a high-power 450-nm semiconductor blue laser in the treatment of benign prostate hyperplasia

Comparative analysis of the safety and efficacy of 1470-nm diode laser enucleation of the prostate and plasmakinetic resection of prostate in the treatment of large volume benign prostatic hyperplasia (>80 ml)

OBJECTIVE

To compare the efficacy and safety of 1470-nm diode laser enucleation of the prostate (DiLEP) with that of plasmakinetic resection of the prostate (PKRP) in treating patients with large benign prostatic hyperplasia (BPH > 80ml).

METHODS

The clinical data from 211 cases of BPH (>80 ml) were collected for analysis. The patients were divided into two groups: the PKRP group (n = 118) and the DiLEP group (n = 93), based on the surgical method used.

RESULT

The DiLEP group demonstrated significantly lower surgical time (p < 0.001), intraoperative bleeding (p < 0.001), bladder flushing time (p = 0.003), indwelling catheter time (p < 0.005), and length of hospital stay (p = 0.018) compared to the PKRP group. However, the quality of the prostatectomy was significantly higher in the DiLEP group (p = 0.005). The Qmax for the DiLEP group was significantly higher than that of the PKRP group (p < 0.05). Compared to the PKRP group, the incidence of urinary incontinence in the DiLEP group increased significantly 4 weeks post-surgery (p = 0.026), although the need for blood transfusion during surgery was significantly reduced (p = 0.037).

CONCLUSION

Both DiLEP and PKRP are safe and effective methods for treating large-volume BPH. However, DiLEP offers advantages such as more thorough glandular resection, shorter surgical time, reduced bleeding, quicker recovery, and fewer complications.

Laser-Induced Blood Coagulation for Surgical Application: A Scoping Review

There is a lack of evidence-based reviews on the effects of laser irradiation on blood coagulation in the literature, despite a large number of clinical trials. We therefore evaluated the available evidence on laser irradiation parameters used in coagulation of blood to optimize physical parameters. We performed a literature search for recent scientific studies indexed between 2017 and 2023 using the databases of PubMed and ScienceDirect. Articles were selected based on defined inclusion and exclusion criteria, and 78 publications in total were eventually included in this scoping review. The following were found to produce significant benefits in blood coagulation for surgical application: (1) dentistry and oral surgeries: 980 nm, 27 s, 2 W, 1502.7 W/cm2, 26.5 J, 622 J/cm2, 400 μm; (2) urogenital disorders: 532 nm, 4 s, 40 W, 10600 W/cm2, 1.3 J, 424 J/cm2, 600 μm; (3) ophthalmic disorders: 810 nm, 1 s, 1 W, 3540 W/cm2, 0.75 J, 1326 J/cm2, 100 μm; (4) embryological surgeries: 1064 nm, 10 s, 25 W, 35400 W/cm2, 262.5 J, 371000 J/cm2, 332.5 μm; (5) dermatological disorders: 1064 nm, 20 W, 2440 W/cm2, 0.1 J, 24 J/cm2, 670 μm; (6) gastrointestinal disorders: 532 nm, 3 s, 20 W, 1051 W/cm2, 120 J, 26500 J/cm2, 760 μm; (7) neurological surgeries: 2.5 s, 1.5 W, 1035 W/cm2, 2 J, 1584 J/cm2, 385 μm; (8) pulmonary disorders: 1320 nm, 5s, 35 W, 12450 W/cm2, 250 J, 65000 J/cm2, 700 μm (9) cardiovascular disorders: 1064 nm, 16.5 s, 5 W, 1980.5 W/cm2, 900 J, 760 J/cm2, 400 μm. In conclusion, our scoping review identifies that combining data from all clinically heterogeneous studies suggests that laser irradiation reflects an effective method for inducing blood coagulation in several medical fields.

450-nm blue diode laser: a novel medical apparatus for upper tract urothelial lesions

OBJECTIVE

To explore the feasibility, safety and effectiveness of the 450-nm blue diode laser (BL), novel blue laser in the treatment of upper tract urothelial carcinomas (UTUCs) and other lesions in a porcine model.

MATERIAL AND METHODS

For in vitro experiment, the ureter tissue was vaporised and coagulated with BL, green-light laser (GL) and Ho:YAG laser (Ho). The efficiency, width and depth of vaporisation, and depth of coagulation were recorded and compared. For in vivo experiments, four swines weighing 70 kg were used. In the acute group, different modes of operations were performed to evaluate the thermal damage, perforation and bleeding. In the chronic group, the overall appearance of the ureter and laser wound healing were observed by the naked eyes and H&E staining 3 weeks after surgery.

RESULTS

In in vitro study, the BL showed a higher efficiency of tissue vaporisation and less tissue coagulation for fresh ureter compared to GL and Ho. In the in vivo study, the power of BL set at 7 W was better, and the thickness of thermal damage varied with different surgery types in the range of 74-306 μm. After 3 weeks, the wound healed well static in vaporisation (SV), moving vaporisation (MV) and H&E staining indicated mucosal healing rather than scar healing.

CONCLUSION

5-10W blue diode laser achieved a higher efficiency of tissue vaporisation and less tissue coagulation in a porcine model, indicating its potential application in the endoscopic surgery of UTUC as an optional device with high performance and safety.

Wound healing process in beagles after vaporization of the prostate with a novel 200W 450-nm laser

In comparison to other commercially used lasers, the coagulation layer of the novel 450-nm laser is thinner, and this coagulation layer's thickness is a key factor influencing wound healing. In this study, we investigated whether the novel 200W 450-nm laser system (BR6800, Blueray Medical Ltd., Shaanxi, China) is superior to classic transurethral resection of the prostate (TURP) for wound healing in beagles. Twenty-two 6-to 8-year-old male beagles were treated with TURP or blue laser vaporization of the prostate (BLVP). Prostate wounds were observed via cystoscopy at 3 h and at 1, 2, 3, and 5 weeks post-operation (two beagles per group). Additionally, two elderly beagles without surgery served as normal controls. After cystoscopy examination, prostate samples were collected and fixed for hematoxylin and eosin (H&E) and immunofluorescence staining to observe wound healing progression under microscopy. The urethras of prostates under cystoscopy in BLVP groups were healed three weeks after surgery, while in the TURP group, they were healed five weeks after surgery. H&E staining confirmed that the coagulation necrosis layer in the TURP group was thicker than that in the BLVP group and it took longer to remove coagulation necrosis after surgery. Macrophage polarity transformation was also earlier in the BLVP group. The new 200W 450-nm laser was superior to TURP for wound healing. The thinner coagulation layer of the 450-nm laser was the primary reason for this process.

Efficacy and safety of a novel 450 nm blue diode laser versus plasmakinetic electrocautery for the transurethral resection of non-muscle invasive bladder cancer: The protocol and result of a multicenter randomized controlled trial

Objectives

To be the first to apply a novel 450 nm blue diode laser in transurethral resection of bladder tumor (TURBt) to treat patients with non-muscle invasive bladder cancer (NMIBC) and evaluate its efficacy and safety during the preoperative period compared to the conventional plasmakinetic electrocautery.

Materials and Methods

Randomized controlled trial (RCT) in five medical centers was designed as a non-inferiority study and conducted from October 2018 to December 2019. Patients with NMIBC were randomized to the blue laser or plasmakinetic electrocautery group for TURBt. As the first study to evaluate this novel blue laser device, the primary outcome was the effective resection rate of bladder tumors, including effective dissection and hemostasis. The secondary outcomes were the perioperative records, including surgical time, postoperative indwelling catheter time, hospital stay length, blood loss, reoperation rate, wound healing and adverse events.

Results

A total of 174 patients were randomized to either the blue laser group (85 patients) or plasmakinetic electrocautery group (89 patients). There was no statistical significance in the clinical features of bladder tumors, including tumor site, number and maximum lesion size. Both the blue laser and plasmakinetic electrocautery could effectively dissect all visible bladder tumors. The surgical time for patients in the blue laser group was longer (p=0.001), but their blood loss was less than that of patients in the control group (p=0.003). There were no differences in the postoperative indwelling catheter time, hospital stay length, reoperation rate or other adverse events. However, the patients undergoing TURBt with the blue laser showed a faster wound healing at 3 months after operation.

Conclusion

The novel blue laser could be effectively and safely used for TURBt in patients with NMIBC, and this method was not inferior to plasmakinetic electrocautery during the perioperative period. However, TURBt with the blue laser may provide the benefit to reduce preoperative blood loss and accelerate postoperative wound healing. Moreover, longer follow-up to confirm recurrence-free survival benefit was required.

A novel 450-nm laser-mediated sinoporphyrin sodium-based photodynamic therapy induces autophagic cell death in gastric cancer through regulation of the ROS/PI3K/Akt/mTOR signaling pathway

BACKGROUND

Photodynamic therapy (PDT) has become an ideal and promising therapeutic method for fighting cancer, but its common application in clinical practice is prevented by the limitations of expensive devices in light sources and phototoxicity in photosensitizers. The aim of this study was to explore the antitumor efficiency of the novel 450-nm blue laser (BL) combined with sinoporphyrin sodium (DVDMS)-mediated PDT against human gastric cancer (GC) in vitro and in vivo, focusing on autophagy pathway.

METHODS

Cell viability was detected by Cell Counting Kit-8 and colony formation assays in HGC27, MGC803, AGS, and GES-1 cells. Cell apoptosis was measured by flow cytometry and western blotting. The production of reactive oxygen species (ROS) was measured by fluorescence microscopy and flow cytometry. Autophagy was determined by transmission electron microscopy and western blotting. The antitumor effect of BL-PDT in vivo was detected by a subcutaneous tumor model in nude mice.

RESULTS

The novel 450-nm laser-mediated DVDMS-based PDT caused remarkable growth inhibition and apoptosis induction in GC cells in vitro by the production of excessive ROS. Autophagy flux was induced by BL-PDT in GC cells, as determined by LC3 conversion assay, LC3 turnover assay, and mRFP-GFP-LC3 puncta assay. Furthermore, autophagy induction was demonstrated to positively contribute to BL-PDT-induced apoptotic effects on GC cells. Mechanically, ROS/PI3K/Akt/mTOR pathway was identified to involve in the regulation of BL-PDT-induced autophagy as determined by transcriptomic analysis and functional studies. Consistently, xenograft studies confirmed the significant antitumor effect of BL-PDT and its favorable safety in vivo.

CONCLUSIONS

The novel 450-nm laser-mediated DVDMS-based PDT may be a safe and effective approach against GC. Our results thus provide compelling evidence for the therapeutic application of BL-PDT in human GC.

Lasers for benign prostatic hyperplasia (hybrid, blue diode, TFL, Moses). Which one to choose?

PURPOSE OF REVIEW

To present the evidence of latest developments of lasers for the surgical treatment of benign prostatic hyperplasia (BPH). We focused on recent advancements in Ho:YAG laser such as Moses technology, the Thulium Fiber Laser (TFL), the blue diode laser, and hybrid laser.

RECENT FINDINGS

Laser enucleation of prostate techniques using either Ho:YAG laser with the Moses technology and Moses 2.0, or TFL seem efficient and safe compared with the standard enucleation using Ho:YAG laser. Only in vitro studies evaluated the blue diode laser and hybrid laser (combination of a continuous wave TFL and blue diode laser). Blue diode laser showed intermediate incision depth and minimal coagulation depth compared with Ho:YAG laser and Super Pulse TFL. Hybrid laser showed deep incision depth and small coagulation area compared with Ho:YAG laser and continuous wave TFL.

SUMMARY

Surgical treatment of BPH using Moses technology, Moses 2.0, and TFL shows encouraging results comparable to the standard enucleation using Ho:YAG laser. Only in vitro data are currently available for blue diode laser and hybrid laser. Future well-designed studies comparing these technologies and evaluating them on specific risk groups of patients as well as the long-term durability of outcomes are needed.