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has confused physicians since its description , and today surgeons believe it is primarily the result of acquired conditions.2 psd is a chronic , painful condition that typically occurs in the intergluteal region and is mainly observed in young adults .
numerous operative and conservative treatments have been described for the management of psd ; however , there is still debate on the ideal treatment .
the surgeon needs to know the dimensions , location , borders , and branches of the pilonidal sinus cavity in order to plan the operative strategy .
if the sinus tract is irregular or too large , however , alternative surgical approaches such as the limberg flap or secondary healing may be needed .
palpation and methylene blue injection are typically used to estimate the borders of diseased tissue ; however , most operative findings do not mach the actual borders . to date
, no clinical study has described the sinus tract using ultrasonography prior to surgery in psd patients .
the aim of this prospective study was to evaluate the borders , opening , and location of the sinus nest prior to surgery using ultrasonography .
with institutional approval and written informed consent , this study included 73 patients who underwent surgery for psd of the sacrococcygeal region .
we carried out this prospective study at the etimesgut military hospital , ankara , turkey from april 2004 to december 2004 .
the data obtained were age , gender , body mass index ( bmi , kg / m ) , past history of drainage , type of disease ( primary or recurrent ) , duration of the symptoms , and number of orifices .
all patients were examined by the same surgeon , and the borders of the sinus tissue were marked on skin according to palpation prior to surgery .
the surgeon also made a treatment plan considering the diseased tissue and marked a possible incision line .
examinations were performed with the use of a 7.5-mhz linear probe on a logiq 5 pro ultrasound scanner ( general electric , usa ) . according to the ultrasonographic evaluation ,
the margins , extensions , sinus tract , branches , and openings of the pilonidal sinus tissue were determined and marked on the patient in a different color .
all scanning was performed by the same radiologist , and power doppler mode was used when needed .
the most suitable surgical treatment was decided for each patient according to the information obtained by the ultrasonography .
the differences between groups were tested for significance by an independent samples t - test .
all patients were males with an average age of 23.03  3.05 ( range 1836 ) years .
three patients ( 4.1% ) had recurrent disease and required one or more additional procedures .
the ultrasonographic borders of the sinus tissue were similar to the borders marked by the surgeon in 56 patients ( 76.6% ) . in the remaining 17 patients ( 23.3% ) , ultrasonography detected branches or borders that distinctly exceeded the planned incision line .
the surgeon had to change the incision line in 14 patients and the surgical approach in three patients after ultrasonographic examination .
in these three patients , the surgical intervention was planned as an ellipsoidal excision and primary closure .
after ultrasonographic examination , the surgeon decided to make a limberg flap in two patients and to leave the sinus open for secondary healing in one patient because these patients had two or three lesions located outside the intergluteal line . in all patients ,
all lesions were found in the incision line , and ultrasonography revealed the entire sinus tract and its branches .
sixty - five patients ( 89.2% ) had one lesion , seven patients ( 9.5% ) had two lesions , and one patient ( 1.3% ) had three lesions . in eight patients , the surgeon was unable to determine whether there was more than one sinus tissue .
ultrasonography detected 1.24  0.91 ( range 04 ) orifices that led to the pilonidal sinus tissue , and 2.76  1.51 ( range 17 ) orifices were found during physical examination .
the mean bmi of the patients was 24.83  2.65 ( range 17.7234.16 ) kg / m .
we performed 56 ( 76.8% ) ellipsoidal excisions and primary sutures , 15 ( 20.5% ) limberg flap procedures , and two ( 2.7% ) marsupializations .
wound infections developed in two patients ( 2.7% ) , hematoma occurred in one patient ( 1.3% ) , and there was no wound dehiscence after the removal of sutures in all patients .
the rate of recurrence within a median 18-month follow - up was 2.7% of the cases .
pilonidal sinus disease is a painful and chronic condition that occurs in the intergluteal region.1 today , the acquired theory has gained general acceptance .
karydakis stated that three factors are required for hair penetration : the invader , consisting of loose hair , a force that causes hair insertion , and vulnerability of the skin to the insertion at the depth of the natal cleft.3 pilonidal sinus disease can be diagnosed easily by surgeons ; however , the main problem after surgery is recurrence .
excision of the nest continues to be the most widely practiced surgical technique for treating psd .
surgical treatment was previously derived from the prevalent pathogenesis theory . when the congenital theory was accepted , the recommended treatment was the excision of the cysts and surrounding tissue to the postsacral fasia in an attempt to eliminate all congenital islands of the epithelium .
since the theory of acquired disease has prevailed , however , dissection has been limited to the pilonidal cyst / sinus itself and the immediate surrounding inflammatory tissue and does not routinely include excision of the deeper layers.4 various surgical methods have been used to treat psd , the most common of which is excision and primary closure for small lesions . for larger and multiple sinuses ,
however , the wound is left open to be closed by a secondary repair or flap rotation after excision of the lesions .
these are primary closure , z - plasty , w - plasty , v - y fasciocutaneous flap , rhomboid flap ( dufourmentel or limberg flap ) , and a gluteus maximus rotational flap.58 the aim of the surgery is to remove all the sinus tissue . leaving hair containing tracts without excision may be one cause of recurrent disease .
some surgeons therefore dye the nest with methylene blue intra - operatively to completely visualize tracts for subsequent curative excision . in some cases ,
sinus nests can rupture , and methylene blue can spread into the operation field and prevent the visualization of the pilonidal sinus tissue .
, the surgeon chooses the operation type according to the location of the openings , extension of the lesion , and depth of the natal cleft .
in particular , the type of flap should be drawn on the skin before the procedure .
if the diseased tissue extends into unexpected areas , the surgeon should not modify the skin incision shape during flap surgery . for this reason , accurately determining the diseased tissue border before surgery is essential .
the number of openings was not detected as well by ultrasonography compared to macroscopic examination of the surgical specimen .
this lack indicates that not all openings reached the diseased tissue ( i.e. , the methylene blue injection was unable to fill the entire lesion ) .
palpation does not yield enough information to determine the borders of the diseased tissue . in our study ,
. the location and dimension of lesions could play an important role in deciding surgical intervention . today
, many surgeons use methylene blue injection or palpation to identify the margins of the diseased tissue . in our cohort , these methods were unable to identify the borders of diseased tissue in all patients .
the diseased tissue should be placed in the excised area , especially in flap surgery , because of the difficulty in modifying the incision line during surgery . in our study
, we found that the pilonidal sinus tract and its branches could be accurately identified using ultrasonography .
the surgeons who took part in this study determined the surgical plan according to the localization of the diseased tissue based on the ultrasonography findings .
this study showed that the sinus tract , branches , and borders could be accurately identified by ultrasonography and that this method can be employed while deciding upon a surgical intervention for pilonidal sinus patients .
purposeto study the benefits of ultrasonography for detecting the borders of pilonidal sinus tissue . 
 the correlation between physical and ultrasonographic examination was used for surgical planning.methodbetween april and december 2004 , 73 patients were recruited for this study . 
 all patients were examined , and the borders of the sinus tissue were marked on the skin according to palpation before surgery . 
 the surgeon also made a treatment plan considering the diseased tissue and marked a possible incision line . 
 patients were subsequently examined with ultrasonography . according to the ultrasonographic evaluation , 
 the margins , extensions , and openings of pilonidal sinus tissue were determined and marked on the patient in a different color by a radiologist prior to surgery . 
 the most suitable surgical treatment was decided according to the information obtained by ultrasonography.resultsthe average age was 23.03  3.05 ( range 1839 ) years . 
 we found 81 lesions in 73 patients . 
 ultrasonographic borders of sinus tissue were similar to the borders marked by the surgeon in 56 patients ( 76.7% ) . in the remaining 17 patients ( 23.3% ) , ultrasonography detected branches or borders that distinctly exceeded the planned incision line . 
 after ultrasonographic examination , the surgeon changed his incision line in 14 patients and the surgical intervention in 3 patients.conclusionpalpation and methylene blue injection do not provide appropriate information in many patients . 
 our study revealed that pre - operative ultrasonography can improve the identification of the sinus tract and its branches when compared to palpation and methylene blue injection .