document: little is understood about this condition 's mechanism , exacerbating factor , and definite treatment . 
   hyperhidrosis generally occurs in the axillae , the palms , plantar surface of the feet , and the face . 
   it is estimated to affect 0.6 to 1.0% of the population , generally young adults . 
   the principal characteristics of this condition include intense discomfort experienced by the patients , affecting their social , affective , and professional lives . 
   primary hyperhidrosis generally manifests in childhood and early adolescence , does not occur during sleep , and can be exacerbated by emotional stress . 
   excessive sweating of the palms and axillae can cause utmost embarrassment in professional and social interaction . 
   the fact that such sweating is not socially accepted , and the discomfort , odor , and stained clothes caused by constant wetness significantly decrease quality of life ( qol ) . 
   although various treatment options are available , including topical and systemic therapies , iontophoresis , regional nerve block , and botulinum toxin injection , have their limitations . 
   video - assisted thoracoscopic sympathetic surgery has been accepted globally as a form of treatment for primary palmar hyperhidrosis . in the literature , different methods , including resection ( sympathectomy ) , transection ( sympathicotomy ) , and clipping 
   much effort to reduce compensatory hyperhidrosis and determine its contributory factors has been attempted during surgical procedures . 
   it has been used to reduce severe compensatory hyperhidrosis related to the procedural level of the sympathetic chain . 
   procedures that involve r3 or / and r4 sympathetic ganglions are widely accepted in many treatment centers , and the results have been favorable . however , some patients still present with postoperative compensatory sweating or overly dry hands . 
   the aim of this study was to compare two simplified methods for the treatment of palmar and axillary hyperhidrosis , in which the sympathetic chain was transected in merely one segment at the level of either the third or fourth rib , respectively referred to as r3 or r4 sympathicotomy . 
   emphasis was placed on comparing the impact of sympathicotomy at r3 and r4 , and to evaluate the efficacy and adverse effects of palmar and axillary hyperhidrosis by surgery . 
   between january of 1999 and april of 2009 , 133 patients with primary hyperhidrosis underwent video - assisted thoracic sympathicotomy . there were 62 males and 71 females , with a mean age of 22.56.5 years . 
   the most common clinical manifestation of hyperhidrosis was palmer and axillary sweating ( in 39.9% ) , followed by palmer sweating alone ( in 33.8% ) , and axillary sweating alone ( in 26.3% ) . 
   the severity of palmar sweating , sweating in other parts of the body , other concomitant symptoms and past medical history were recorded . 
   chest radiography , electrocardiogram ( ecg ) and routine blood examination were performed before surgery . 
   severe primary palmar hyperhidrosis that significantly interfered with daily life , including work , was the common primary indication for surgery . 
   secondary hyperhidrosis caused by hyperthyroidism or neurotic anxiety , and patients with bradycardia ( heart rate < 60/min ) were excluded from surgery . 
   patients were randomized into two therapeutic groups ( table 1 ) . patients were placed under single lumen intubation general anesthesia in the semi - fowler 's position ( dorsal decubitus position with back lifted 45 degrees from horizontal , and abduction of both arms ) . 
   a 2 mm trocar was introduced into the pleural cavity through the fourth intercostals space of the mid - axillary line . 
   after thoracoscope insertion , an initial panoramic view of the upper pleural cavity and mediastinal structures was obtained . 
   another operating channel ( 2 mm ) was made through the fourth intercostal space of the anterior axillary line . 
   after identification of the thoracic sympathetic ganglion , the t3 or t4 sympathetic chains were then destroyed by electric cautery . the anesthesiologist re - inflated the lung . 
   following lung re - expansion by positive inflation with a 6 fr feeding catheter , the trocar was then removed . 
   the patients were asked simple questions related to symptom resolution , surgical outcome satisfaction , and occurrence / intensity of reflex sweating . 
   compensatory sweating in the other regions of the body was graded as " none " when compensatory sweating was not noticeable and did not interfere with daily activities , " mild " when it was tolerable but sometimes interfered with daily activities , " moderate " when it was barely tolerable and frequently interfered with daily activities , and " severe " when it was intolerable and always interfered with daily activities . 
   the degree of satisfaction in each patient was recorded as " satisfied " or " dissatisfied " . 
   self - reported satisfaction , recurrence , and improvement of sweating after intervention constituted the three recorded aspects of the patients ' subjective experience with sweat - triggering situations . 
   recurrence was defined as severe discomfort experienced by patients similar to that experienced before surgery , despite improvement in sweating . statistical analysis of comparisons between the 2 groups was conducted using the student 's unpaired t test and chi - square test with spss 13.0 ( spss , inc , chicago , il ) . 
   all operations were successfully performed using video - assisted thoracoscopy without associated severe morbidity and mortality . no life - threatening event or death occurred and 
   other complications , such as horner syndrome , hemothorax , intercostal neuralgia , pulmonary edema and atelectasis were not observed . 
   mild subcutaneous emphysema and residual pneumothorax on follow - up chest radiograph resolved spontaneously , and no further therapy was required . 
   there was no significant difference between the 2 groups in terms of age , sex , and positive family history ( table 1 ) . 
   in addition , there was no significant difference between the 2 groups in the rate of satisfaction and recurrence . 
   the incidence of " moderate " to " severe " compensatory sweating was higher in the r3 ( 71.8% ) group than r4 ( 33% , p=0.02)(table 2 ) . 
   no patient requested reoperation in either group , and no patient expressed regret after surgery . 
   the dominating indication for sympathetic surgery is hyperhidrosis of the upper limb . when conservative and medical treatment fails , endoscopic thoracic surgery is performed . 
   the first sympathectomy for the treatment of hyperhidrosis was performed in 1920 , in which anterior cervical access was used . in 1942 , 
   great advance in surgical technique was made , which rendered it unnecessary to sacrifice the stellate ganglion in order to denervate the upper limb . 
   as such , one of the most feared complications in thoracic sympathectomy - claude bernard - horner syndrome - was eliminated . in this study , patients were informed about the possible side effects of sympathicotomy , including compensatory sweating , prior to the procedure . 
   chou et al . asserted that reflex response in the sweating center of the hypothalamus could cause the underlying mechanism of compensatory sweating . 
   according to previous studies , various factors , such as the location of hyperhidrosis , sympathicotomy level , and surgical procedures including clamp , cut and resect can induce compensatory sweating . 
   also , the severity of compensatory sweating is influenced by patient condition , such as obesity , primary complaint severity and t2 sympathetic ganglion resection . 
   therefore , more selective sympathicotomy was proposed to minimize side effects , by lowering the level to preserve sympathetic tone in place of upper t2 sympathicotomy or multilevel sympathicotomy . 
   selective sympathicotomy is an effective surgical method to eliminate compensatory sweating in the treatment of hyperhidrosis . 
   although compensatory sweating remains the main secondary effect , numerous studies have reported that sympathicotomy is a safe and effective procedure for the management of hyperhidrosis and reduction of compensatory sweating . 
   the frequency and severity of compensatory sweating were reduced , with less interruption of sympathetic trunk in group t4 compared to group t3 ( table 2 ) . 
   this explains the differences at the other levels in sympathicotomy at palmar sweating and compensatory sweating are still controversial topic . 
   lin et al . suggested that postoperative results including compensatory sweating is influenced by changes in the sympathetic tone and disturbance of the reflex arc in the hypothalamus secondary to the procedures of the upper thoracic sympathetic system . 
   furthermore , anatomical variation , a mistake at the level of interruption , and incomplete resection of the sympathetic trunk may also cause compensatory sweating . the high personal expectations of patients could be the reason of dissatisfaction despite the development of minor complications . 
   difference in surgical technique , such as sympathicotomy level and surgical procedure ( clamp , cut and resect ) , and classification of the extent of compensatory sweating could impact on the complication rate . 
   many authors felt that the more sympathetic segments excised , particularly including t2 , the greater the incidence of severe compensatory symptoms . 
   dewey et al .   limited the extent of resection for hyperhidrosis to a single level , and found reduction in the incidence of severe compensatory symptoms . 
   however , until now , no prospective study has been performed to compare r3 and r4 single level sympathicotomy for the treatment of palmar and axillary hyperhidrosis . in this study , patients did not experience discomfort in their daily activities . 
   these results suggest that , compared to r3 sympathicotomy , r4 sympathicotomy decreases the extent of side effects but does not compromise efficacy . as such , it should be the method of choice for the treatment of palmar and axillary hyperhidrosis . 
   r3 and r4 have similar success rates in the treatment of palmar and axillary hyperhidrosis .
summary: backgroundvideo - assisted thoracic sympathicotomy plays an important for the treatment of essential hyperhidrosis . 
   patients are usually satisfied with the surgical outcome at the early post - operative period , but suffer recurrence and compensatory sweating in the late post - operative period . 
   there are many sympathicotomy methods to minimize recurrence and compensatory sweating . 
   we compared the outcome of sympathicotomy methods above the third rib ( r3 ) and the fourth rib ( r4 ) with regards to symptoms , satisfaction , recurrence , and compensatory palmar and axillary hyperhydrosis.materials and methodsfrom january 1999 to april 2009 , 39 cases of thoracoscopic sympathicotomy at the third rib ( r3 ) , and 94 cases of thoracoscopic sympathicotomy at the fourth rib ( r4 ) for palmar and axillary hyperhidrosis were compared for early and late post - operative satisfaction , compensatory sweating and recurrence.resultsthere was no sex or age difference between groups . 
   early satisfaction was 94.9% and 98.9% in the r3 group and r4 group , respectively . 
   there was no difference in early satisfaction ( 94.9% in r3 and 98.9% in r4 ) , late satisfaction ( 84.6% in r3 and 89.4% in r4 ) , or recurrence ( 17.9% in r3 and 17.0% in r4 ) between groups . 
   there was significant difference in compensatory sweating ( 71.8% in r3 and 33% in r4 , p=0.002).conclusionr4 sympathicotomy demonstrated superior efficacy in the treatment of compensatory sweating compared to r3 in palmar and/or axillary hyperhidrosis .