1. Introduction

Pilonidal sinus disease (PSD) is a painful disorder usually found in the natal cleft; it is diagnosed by the presence of a characteristic epithelial track between the buttocks . The sinuses may be caused by hair growing into the skin where there is excessive body hair or if tight clothing is worn, and is often seen in occupations that involve sitting for long periods[1].

PSD is a problem suffered mostly by young men, with an incidence of 26 per 100,000 population, affecting men twice as often as women[2] with symptoms of recurrent infection of the area of the natal cleft[3]. The clinical presentation of the disease varies from asymptomatic pits to painful draining abscesses and chronic fistulae. The most common manifestation of pilonidal disease is a painful fluctuant mass in the sacrococcygeal region[2].

Many treatment options for pilonidal sinus have been reported including , antibiotics, drainage, and excision surgical treatment. Different modalities of surgery have been used, but they often result in recurrence, and additional surgery is needed[4]. Laser hair epilation in the affected area have shown beneficial effect by decreasing the risk of recurrent pilonidal sinus disease[5].

Laser depilation is used in a number of medical conditions, such as ingrown hairs, hirsutism (male pattern of hair distribution in females), and folliculitis (inflammation around the hair follicle), as well as PSD. Lasers emit specific wavelengths of light that are absorbed by a different colour in the tissue, known as chromophore, and are converted into heat. The chromophore for laser hair removal is melanin; since this is lacking in light hairs, laser hair removal treatments are better suited to people with darker hairs[6].

Laser has been available as a permenant method for hair removal[7]. Multiple sessions are often needed and seem to increase progressively the hair free period between sessions and decrease hair regrowth[8].

2. Patients and Methods

This study was done on 18 patients, 16 males and 2 females with pilonidal sinus attended to out patient’s clinic in Al Azhar university hospitals and other hospitals .Age of patients ranged from 17– 30 years. 11 Patients had primary disease and 7 had recurrent disease. All of patients underwent surgical intervention by open technique in which the whole sinus was excised and the wounds left open for healing by secondary intention. After complete wound healing , patients were divided into 2 groups: Group A: 9 patients were treated with alexandrite Laser for hair removal after application of local anesthesia cream eutectic mixture of prilocaine 2.5% and lidocaine2.5% (EMLA CREAM). The Laser system protocol was:

1-Laser system: Cynosure Apogee 5500

2-Wavelength (nm): 755

3-pulse duration (ms): 3

4-Fluence (J/cm2):18-20 according to skin type of each patient.

5-spot size (mm):12 -15

6-sessions (n):3- 5

7-Time interval (weeks):4-6

Group B: 9 patients were using traditional methods for hair removal (shaving, and hair removal creams).

All patients were followed up for about one and half years, every 2 months for 6 month, and every 3 months for 1 year.

Written informed consent from all study patients was taken.

3. Statistical Analysis

All statistical calculations were done using computer programs.Microsoft excel version 10 and spss (statistica package for the social science version 20.00) statistical program. at 0.05, 0.01 and 0.001 level of probability [9] .Comparison of percentage was done using the t test and chi square were presented using percentage, mean ± standard deviation. The Pearson linear correlation coefficient was estimated to show the relationship of the physiological parameter to each other[10].

4. Results

Demographic data, type of lesion, method of hair removal and recurrence after treatment were shown in table 1.

Our study was done on 18 patients, 16 were males (89%) and 2 were females (11%) with age ranged from 17 to 30 years, with a mean age of 22.3+0.7 years. 11 patients(61.1%) had primary lesion, while 7 patients (38.9%) had recurrent lesion. Group A patients had a mean age 21.33±3.94 years, 8 (88.9%) were males, 5 (55.6%) were primary cases and 4(44.4%) were recurrent. Patients in Group A underwent Laser hair removal at the natal cleft after complete wound healing and according to the explained protocol. Group B patients had a mean age 23.33±3.60 years, 8 (88.9%) were males, 6(66.7%) were primary cases and 3(33.3%) were recurrent. Group B patients use the traditional methods for hair removal (table 2, 3),(Figure 1,2). Patients in Group A mentioned that the Laser hair removal was comfortable with no complications while those in group B reported difficulty in maintaining hair removal at regular periods.

Recurrence occurred in 4(44.4%) in Group B while there were no recurrence in Group A and this difference was statistically significant. (Table 3), (Figure 3)

Table 1. Demographic data, clinical data, method of hair removal and recurrence after treatment Patient Sex Age Lesion method of hair removal Recurance after ttt 1 Male 17 primary laser : 4 sessions No 2 Male 22 recurrent Laser : 5 sessions No 3 Male 24 recurrent Laser :3 sessions No 4 Male 18 primary Laser :4 sessions No 5 Male 29 recurrent Laser :4 sessions No 6 Male 17 primary Laser : 5 sessions No 7 Male 20 primary Laser :3 sessions No 8 Male 21 primary Laser :4 sessions No 9 Female 24 recurrent laser :3 sessions No 10 Male 22 primary Shaving No 11 Male 23 primary Shaving Recurrence 12 Male 25 primary Shaving No 13 Male 30 recurrent Shaving Recurrence 14 Male 18 primary Shaving No 15 Male 23 primary Cream Recurrence 16 Male 24 recurrent Cream No 17 Male 26 recurrent Cream Recurrence 18 Female 19 primary Cream No Group (A): Patients from 1 to 9. Group (B): Patients from 10 to 18.

Table 2. Comparison between studied groups as regards age Mean±SD T test P value Group A 21.33±3.94 1.124 0.278 NS Group B 23.33±3.60

Table 3. Comparison between studies groups as regards sex, type of lesions and recurrence after treatment Group A Group B Chi square P value Sex MaleN=16 8 (88.9%) 8 (88.9%) 0.000 1.000 NS FemaleN=2 1(11.1%) 1(11.1%) Type of lesions Primary N=11 5 (55.6%) 6(66.7%) 0.234 0.629 NS Recurrent N=7 4(44.4%) 3(33.3%) Recurrence No recurrence 9 (100%) 5 (55.6%) 5.143 0.023 S Recurrence 0(0%) 4(44.4%)

Figure 1. Comparison between studies groups as regards Recurrence

5. Discussion

Pilonidal disease is a chronic disease of the natal cleft that causes both discomfort and embarrassment to sufferers. Recurrent follicular infection is the causative factor. It is often resistant to treatment so its treatment remains in question. Surgical treatment has a significant failure rate, and recurrence is common. The aim of the treatment of pilonidal sinus includes excising and healing with decrease recurrence rate[11]. The origin of pilonidal sinus has been a subject of interest for many years. It was thought to be of congenital origin, involving the remnant of the medullary canal and the infolding of the surface epithelium or a faulty fusion of the cutaneous covering in the early embryonic stage[2] but now it was believed that the majority of pilonidal disease cases are acquired and the result of a foreign body response to entrapped hair[12]. After the onset of puberty, sex hormones affect the pilosebaceous glands, and the hair follicles become distended with keratin. As a result, a folliculitis is created, which produces edema and follicular occlusion. The infected follicle extends and ruptures into the subcutaneous tissue, forming a pilonidal abscess. This results in a sinus tract that leads to a deep subcutaneous cavity. The laterally communicating sinus overlying the sacrum is created as the pilonidal abscess spontaneously drains into the skin surface³. Loose hair is sucked into the pilonidal sinus by friction and movement of the buttocks whenever the patient stands and sits. This trapped hair stimulates a foreign body reaction and infection[13]. Excess hair in and around the gluteal cleft increase the risk of the occurrence of the disease, and the frequency and severity of recurrences are directly related to the density of the hair present on the buttocks. Long-lasting or permanent hair removal in the gluteal area in pilonidal sinus disease would eliminate the hair decreasing the risk of recurrent disease[14]. Benedetto and Lewis[12] reported that the 800 nm diode laser may be an effective tool in the treatment of pilonidal sinus disease. Presence of large amounts of hair in the lower back is one of the risk factors that increase the chance of pilonidal sinus development. By eliminating the source of hair and hair fragments that course along the surface of the lower back and buttocks, interruption of the etiologic source for pilonidal sinus disease can be accomplished[14].

There are recent reports that Laser hair removal in the area may be effective treatment for pilonidal cysts[15].

Lavelle et al.,[16] said that laser treatment for pilonidal sinus, either as primary treatment or as an adjunct to surgery in refractive cases. It could also be useful in preventing the growth of hairs into wounds that have been left open and allowed to granulate.

Oram et al.,[17] suggest that laser hair removal after surgical interventions in pilonidal sinus disease decreases the risk of recurrence over the long term.

Our study meets with these studies in the effect of the Laser hair removal after pilonidal sinus excision decrease the rate of recurrence.

6. Conclusions

Laser hair removal after surgical interventions in pilonidal sinus disease decreases the risk of recurrence. We recommend laser epilation to every patient with pilonidal sinus disease as an adjunct treatment after the surgical treatment.