Effects of various laser wavelengths and energy levels on pig rectal submucosal tissue

Multilayered numerical modelling of bio-thermal aspects during laser assisted treatment of internal haemorrhoid developed in rectum

Haemorrhoids are swollen blood vessels developed around the anus. Internal haemorrhoids are generally not visible from outside due to its growth inside the rectum and it is generally considered as painless. However, a prolapsed internal haemorrhoid may cause discomfort, pain and irritation. For the treatment of internal haemorrhoid, laser assisted therapy would be helpful due to its rooted advantages such as post-surgery minimal pain, lesser bleeding, quicker healing, shorter recovery period, shorter surgical and overall treatment duration, lower risk of recurrence and least risk of post-surgical infections. The genesis of present research work deals with the development of mathematical modelling to capture the bio-thermal response during laser assisted therapy of internal haemorrhoid developed in the rectum. The explicit form of finite difference method is employed as numerical tool for the mathematical study and the physical domain is considered as multilayered tissue (three different layers of rectum: muscle, submucosa and mucosa). A Gaussian laser beam is considered as heat source to destroy the abnormal growth inside the rectum. Temperature variation in multi-layered tissue is investigated for laser heat input and absorption radius along the temporal and spatial coordinate. Temperature drop has been evidenced in the interfaces of multi-layered rectum tissue. The research outcome is verified with the published numerical model with negligible variation.

Laser technology in proctological diseases: is it really the wave of the future?

Different types of lasers have been applied for various proctological conditions. We discuss about published articles regarding the application of lasers, with concern about evidence-based use of these techniques and technologies. We performed a literature search about laser treatments for proctological conditions. 55 studies were included for the final revision. Meta-analysis of data was not performed because of heterogeneity of study designs and outcome measures. A scoping review was performed. Laser treatments for hemorrhoids require a shorter operative time and show less postoperative pain and bleeding compared to conventional hemorrhoidectomy, but are more expensive. Studies are heterogeneous in design, endpoints, postoperative assessment, length of follow-up and outcome measures. Only 3 RCTs are available and only three studies evaluate long-term outcomes. FiLaC (fistula laser closure) was initially described in 2011 for the treatment of anal fistula. In the published studies the reported healing rates vary between 20 and 82%, and the ideal indication is yet to be defined. Studies with long-term follow-up are lacking. SiLaT (sinus laser treatment) applied the technology used for FiLaC to the treatment of pilonidal sinus disease. This technique had less perioperative pain and shorter hospital stay, but a lower primary healing rate when compared to traditional techniques. Available data is very limited, and no randomized trials are published to date. Laser assisted techniques are a viable, minimally invasive, but expensive option for the treatment of several proctological conditions. Further researches are needed to assess if patients could benefit of their use, and for what indication.

Non-excisional laser therapies for hemorrhoidal disease: a systematic review of the literature

Non-excisional laser therapies are emerging treatment for grades II and III hemorrhoidal disease (HD). However, so far, their efficiency is based on low-level evidence. Therefore, we aimed to systematically review the efficiency of non-excisional laser therapies for HD. MEDLINE/Pubmed, Web of science, Embase, and Cochrane were searched from database implementation until the April 17th, 2020. We included studies reporting at least one of surgical indicators of postoperative outcomes of laser therapies, encompassing laser hemorrhoidoplasty (LH) and hemorrhoidal laser procedure (HeLP). Fourteen studies describing LH and HeLP were included, representing 1570 patients. The main intraoperative complication was bleeding (0-1.9% of pooled patients for LH, 5.5-16.7% of pooled patients for HeLP). Postoperative complications occurred in up to 64% of patients after LH and 23.3% after HeLP. Resolution of symptoms ranged between 70 and 100% after LH and between 83.6 and 90% after HeLP. Moreover, four randomized controlled trials included in our review reported similar resolution after LH compared with hemorrhoidectomy or mucopexy and after HeLP compared with rubber band ligation. Recurrence rate was reported to range between 0 and 11.3% after LH and between 5 and 9.4% after HeLP. When compared with hemorrhoidectomy, LH showed conflicting results with one randomized controlled trial reporting similar recurrence rate, but another reporting decreased recurrences associated with hemorrhoidectomy. Laser therapies showed lower postoperative pain than hemorrhoidectomy or rubber band ligation. LH and HeLP are safe and effective techniques for the treatment of grades II and III HD.