Introduction

Pilonidal Disease (PD) is a typical ailment in young men [1]. Different forms of treatment include traditional open surgery with or without a flap, phenolization, and laser treatment [2,3,4]. Minimal-invasiveness and quick recovery to daily activities have been considered the advantages of laser procedures when compared to traditional open surgeries [5]. A recent systematic review article included a total of 971 patients; the median healing time after the laser treatment was 17–47 days. However, there have been fewer publications reporting the length of sick leave after the various forms of operations [6,7,8]. The length of sick leave, wound healing time, disease recurrence rate, and hospital stay days are the most important parameters when comparing different techniques. These parameters describe not only the patient’s recovery, but also the costs of the procedure. The superiority of the laser procedure comparing to other mini-invasive treatments like the pit picking has not been studied [9, 10].

The purpose of the study was to publish the short-term results of our first FiLaC™ (Fistula-tract laser Closure) laser PD patients considering the length of sick leave and wound healing time. The secondary purpose was to share our experience of this procedure and describe the changes we have made to the treatment path based on our experiences.

Patients and Methods

This is a case series analysis, which has a research permit from the regional institutional review board (ID164/2021). The study population consisted of 69 consecutive PD patients, who were operated upon with a FiLaC™ laser in the plastic surgery department of a single academic teaching hospital between August 2019 and December 2021. All patients were evaluated before the operation at an outpatient clinic. The patients were selected for surgery if they had PD and a related persistent problem, such as secretion or abscess formation. Smoking cessation was recommended, but this was not considered an exclusion criterion for the operation. Information on the number of antibiotic courses, number of abscess openings, number of fistulas, and daily sitting time was collected from the medical records. The estimated daily sitting time was routinely asked from the patient before the operation.

First operations were performed in the operating room under spinal anesthesia as day surgery. With the accumulation of experience, we moved to local anesthetic procedures. The procedures were performed in the prone position, and hairs were removed from the operation area with a razor. A local anesthetic mixture (20 ml 1% lidocaine/epinephrine + 20 ml 0.9% saline) was injected in the procedure area to prevent heat damage caused by the laser. A single dose of cefuroxime (1.5 g) was administered intravenously preoperatively. Intravenous clindamycin (600 mg) was used for patients with a penicillin allergy. The fistula passages and pilonidal cyst were removed or opened with a 4-mm punch. All hairs were removed with a curette or surgical clamp. Sinus tracts were treated with laser (13 W) at a speed of 1 mm/s. The laser treatment time (s) and energy (J) used were recorded. There were no dressings placed inside the wound. Only a 10 cm × 10 cm fold was taped on the skin. When leaving the hospital, patients were asked to pay attention to the duration of the secretion.

The follow-up was done by phone at 2 weeks and 4 weeks; with this, we wanted to make sure that the patients’ wounds are healing. The outpatient clinic follow-ups were at 6 weeks and 6 months postoperatively. The duration of the secretion was enquired about and recorded. If the situation had not improved over 6 weeks, a repeat operation was considered.

For the statistical analyses, we used IBM SPSS Statistics, version 27. Categorical variables were presented as absolute numbers and percentages. Continuous variables were expressed as the mean ± standard deviation (SD). We used Fisher’s exact test to compare nominal data and the Mann–Whitney U test for nonparametric data. Results were considered statistically significant at p values < 0.05.

Results

In total, 66 patients were included in the study. Three patients were excluded because they underwent a PD operation with another technique before the study. The mean follow-up time was 15.3 SD7.7 months. Majority of the patients were men (n = 47, 71.2%). The mean age was 27.8 SD9.9 years, and the mean BMI was 27.4 SD4.8. The patients had a few comorbidities, with one patient having type 1 diabetes and one patient having type 2 diabetes. There were 16 (24.2%) smokers. The mean sitting time per day was 6.2 SD2.7 h/day. The patients had an average of 1.8 SD1.8 antibiotic regimens before their operation and 35 (53%) patients had experienced an abscess before their operation. Prior to the operation, the mean number of 1.2 SD1.5 abscesses had been opened. Only three (4.5%) patients had continuous need for daily wound care preoperatively.

A mean energy of 894 SD519 J was used, and the mean laser treatment time/patient was 69.7 SD38.5 s. The mean operative time was 19.5 SD7.3 min. A senior surgeon operated on 32 (48.5%) of the patients. The mean number of fistulas were 3.0 SD1.6. Pus was detected in 11 (16.7%) patients during the surgery. The detection of pus did not affect the rate of residual disease (p = 0.942). The mean hospital stay was 0.1 SD0.2 days, and majority of the operations (74.2%) were done under spinal anesthesia. General anesthesia (13.6%) and local anesthesia (12.1%) procedures were also performed. The mean number of sick leave days was 6.2 SD8.9 days, and the mean number of outpatient clinic visits (including phone calls) was 3.4 SD3.9.

The mean secretion time was 22.1 SD20.3 days. During the follow-up, 54 (81.8%) patient´s wounds healed. After the surgery, 17 patients (25.8%) had residual PD at less than 2 months after the procedure. PD relapsed in two (3%) cases more than 2 months after the primary procedure. There were eight (12.1%) patients suffering postoperative wound infection. No other complications were detected. A repeat operation was necessary for 13 (19.7%) patients. The repeat laser operations were performed 4.9 SD3.3 months after the primary operations. There were six (9.1%) patients referred for laser hair removal after the surgery. This had already been done preoperatively for two (3.0%) of the patients.

We also compared the operative results of consultant plastic surgeons and surgeons specializing in the plastic surgery. We noticed that in the operations performed by consultant plastic surgeons, the patients’ wounds healed slightly better and there were fewer repeat operations. However, there was no statistically significant difference between them (p = 0.342, p = 0.218) (Table 1). Patients operated on by consultant plastic surgeon were slightly more challenging, and BMI was statistically significantly higher in patients operated upon by consultant plastic surgeon 28.8 SD5.3 and 25.9 SD3.7 (p = 0.019) (Table 1). Other preoperative parameters such as smoking, BMI, or number of fistulas did not have a significant effect to the rate of residual disease (p = 0–635, p = 0.261, p = 0.520, respectively).

Table 1 Postoperative outcomes of consultant plastic surgeons and surgeons specializing in the plastic surgery
Full size table

Discussion

During the follow-up, 81.8% of wounds healed, which was less than the 94.9% reported in the systematic review by Romic et al. [2]. The BMI of our patients was higher than that in the systematic review article [2]. In addition, several patients had long-term symptoms and abscess formation even before the operation. These factors could have contributed to our results. These results represented the very first patients operated upon with this technique at our institution, and there may have been a slight learning curve affecting the results. In addition, some of the patients were still under follow-up and consequently not classified as healed. We also encountered some unfavourable postoperative wound care despite to our instructions (due to the novelty of this technique and unfamiliarity with it outside our department). It should be noted that these patients were under strict observation. This means that most likely all the wound healing problems were detected and reported. The number of postoperative contacts may vary between different reports and partly affect the results. Otherwise, basic patient characteristics such as age and gender were comparable to those detected in the other PD publications [6, 11, 12].

Our mean wound healing time was significantly shorter than in the systematic review article by Romic et al. but slightly higher than that reported by Dessilly et al. [2, 12]. The length of sick leave was significantly shorter in our study than in Harju’s paper [6]. Nowadays, the sick leave is mostly just the day of the operation. The amount of energy used in the procedures varied greatly, which correlates to the size of the area to be lasered.

Residual disease less than 2 months after the procedure occurred in approximately 25% of patients. It must be noted that it could have also been normal recovery that was just prolonged. Therefore, not all these patients required a re-operation. In the literature, recurrence rates at 60 months vary from 1.9 to 40.4% [13]. The experience of the operating surgeon correlated with the surgical outcome; the trend showed that those operated by consultant plastic surgeons had fewer re-operations. However, statistical significance was not reached.

As our experience has increased, we now perform the procedures in the outpatient clinic under local anesthesia as day surgery. If the procedure area is larger than the size of the palm, we recommend the operation to be performed in the operating room, as well as when the lowest fistula occurs near the anus. For selected patients, laser hair removal was performed either preoperatively or postoperatively. There is no conclusion in the literature regarding the most effective timing [9, 14, 15].

This is a simple cross-sectional study, a case-series analysis with potential selection bias and no comparison group. The number of patients included in the study was also limited. The follow-up time was more than a year, which seems sufficient for this group of patients and is in line with the follow-up time in previous studies [2, 16, 17].

Conclusions

Laser treatment for sinus pilonidal is promising and minimally invasive procedure. The procedure can be performed under local anesthesia in an outpatient setting with a speedy recovery. Studies measuring the quality of life are warranted to support these findings.