Safety and/or effectiveness of methylene blue-guided pilonidal sinus surgery

The effectiveness of methylene blue-guided sacrococcygeal pilonidal sinus disease (SPSD) surgery for the prevention of incomplete excision was evaluated.

It was a prospective randomized clinical trial that included 33 patients diagnosed with SPSD. Before the excision, methylene blue was injected into the opening of each sinus. At the first excision, all areas that were stained with methylene blue were resected along with the opening of the sinus (Group 1). At the discretion of the surgeon, all areas with granulation tissue were macroscopically re-excised as a single specimen (Group 2). Specimens were evaluated based on five microscopic assessment parameters.

All microscopic assessment parameters for SPSD were positive in both the groups. No significant differences were observed between the groups in terms of the positivity of all parameters, except hair shaft (parameter 4) positivity (p > 0.05). Intensities of positivity in Group 1 for all parameters were higher to a statistically significantly degree compared with those of Group 2 (p < 0.05).

The application of methylene blue for guidance in SPSD surgery may cause inadequate excision of the diseased area. In clinical practice, this condition may manifest itself by recurrence and poor wound healing.