***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: OBJECTIVE To compare two surgical techniques ( denervation levels ) for sympathectomy using video-assisted thoracoscopy to treat palmar hyperhidrosis in the long-term . METHODS From May 2003 to June 2006 , 60 patients with palmar hyperhidrosis were prospect ively r and omized for video-assisted thoracoscopic sympathectomy at the T2 or T3 ganglion level . They were followed for a mean of 20 months and were evaluated regarding their degree of improvement of palmar hyperhidrosis , incidence and severity of compensatory hyperhidrosis and its evolution over time , and quality of life . RESULTS Fifty-nine cases presented resolution of the palmar hyperhidrosis . One case of therapeutic failure occurred in the T3 group . Most of the patients presented an improvement in palmar hyperhidrosis , without any difference between the groups . Twenty months later , all patients in both groups presented some degree of compensatory hyperhidrosis but with less severity in the T3 group ( p = 0.007 ) . Compensatory hyperhidrosis developed in most patients during the first month after the operation , with incidence and severity that remained stable over time . An improvement in quality of life was seen starting from the first postoperative evaluation but without any difference between the groups . This improvement was maintained until the end of the follow-up . CONCLUSION Both techniques were effective for treating palmar hyperhidrosis . The most frequent complication was compensatory hyperhidrosis , which presented stable incidence and severity over the study period . Sympathectomy at the T3 level presented compensatory hyperhidrosis with less severity . Nevertheless , the improvement in quality of life was similar between the groups BACKGROUND Compensatory sweating ( CS ) is one of the most common postoperative complications after thoracic sympathectomy , sympathicotomy or endoscopic sympathetic block ( ESB ) for palmar hyperhidrosis . This study was conducted to examine the relevance between CS and the sympathetic segment being transected in the surgical treatment of palmar hyperhidrosis , and thus to detect the potential mechanism of the occurrence of CS . METHODS Between October 2004 and June 2006 , 163 patients with primary hyperhidrosis were r and omly divided into two groups , T(3 ) sympathicotomy ( 78 patients ) and T(4 ) sympathicotomy ( 85 ) , who were operated upon under general anesthesia via single lumen intubation and intercostal video-mediastinoscopy ( VM ) . RESULTS No morbidity or mortality occurred . Palmar hyperhidrosis was cured in all patients . Follow-up ( mean ( 13.8 + /- 6.2 ) months ) showed no recurrence of palmar hyperhidrosis . The difference of rates of mild CS in groups T(3 ) and T(4 ) was of no statistical significance . The rate of moderate CS was significantly lower in group T(4 ) than in group T(3 ) . No severe CS occurred . CONCLUSION The rates of occurrence and severity of CS are lowered with the lower sympathetic chain being transected BACKGROUND Compensatory sweating is a major and troublesome complication noted frequently after sympathectomy in patients with primary palmar hyperhidrosis . This r and omized clinical trial was projected to measure the impact of limited denervation on compensatory sweating while performing endoscopic thoracic sympthectomy . METHODS Two hundred thirty-two patients with primary palmar hyperhidrosis were r and omly allocated to either a T3 sympathectomy treatment , called group T3 , or a T2 - 4 sympathetic treatment , called group T2 - 4 . The patients underwent bilateral sympathetic ablation at corresponding levels . All patients were followed up and evaluated for comparison of symptom resolution , postoperative complication , levels of satisfaction , and severity of compensatory sweating between the two groups . RESULTS Sex , age , family history , and distribution of sweating were similar in both groups . The postoperative complications were minor , and Horner 's syndrome was not detected in either group . The frequency of mild and moderate compensatory sweating was not significantly different between the two groups , but the incidence of severe compensatory sweating was significantly lower after T3 sympathectomy ( 3 % versus 10 % ) . As for satisfaction rate , group T3 was superior to group T2 - 4 ( 96.6 % versus 89.6 % ) . The rate of symptom resolution was 100 % , and no recurrence was found in either group . CONCLUSIONS The single-level sympathetic denervation under thoracoscopy is a safe and effective procedure to treat primary palmar hyperhidrosis . This method reduces the incidence of severe compensatory sweating postoperatively without compromising the patient 's satisfaction Background In this study , patients treated by thoracoscopic sympathicolysis for palmar hyperhidrosis were evaluated to determine the number and response of sweat gl and s to intradermal acetylcholine stimulus . Methods A total of 30 patients were included in the study . Group A consisted of 10 patients with palmar hyperhidrosis who underwent thoracoscopic sympathicolysis in October 2005 , and group B consisted of 20 patients who underwent surgery during the years 1999 , 2000 , and 2001 . The study procedure involved applying iodine alcohol to the palm and then intradermally injecting 0.1 ml 1 % acetylcholine . This activated the sweat gl and s , which were then photographed and counted . The study procedure was performed prospect ively over different periods in group A and retrospectively in group B. Results In group A , the mean number of gl and s activated 1 , 3 , 6 , and 12 months after surgery were 41 , 174.20 , 522.8 , and 747.2 , respectively ; this gradual increase was statistically significant over the first 6 months ( p = 0.004 ) but not between months 6 and 12 ( p = 0.255 ) . The trend towards an increasing number of active gl and s occurred in both groups , with a mean of 1369.8 active gl and s in group B compared to 747.2 ( p = 0.095 ) in group A after 12 months . Conclusion It is well-known that Cannon ’s law of denervation ( 1939 ) is not applicable to the sweat gl and s , that is , there is no hyperactivation following intradermal acetylcholine stimulation . However , some response , which increased over the first 6 months following surgery , was observed in our study . Nevertheless , this activation is subsequently self-limiting , result ing in no gl and atrophy , and reinnervation occurs without patient awareness This study compares the results obtained of video-assisted sympathectomy performed on two distinct ganglion levels ( third vs. fourth thoracic ganglion ) in the treatment of palmar hyperhidrosis ( PH ) , through a blind r and omized clinical trial . All participants were r and omized into two groups of 20 patients ( G3 and G4 ) and underwent the operation , and were followed for 12 months . We used an objective method for measuring sweat , checking the transepidermal water loss ( TEWL ) , and evaluated the quality -of-life ( QoL ) before and after the operation . All patients ( n=40 ) ceased suffering from PH after surgery , with statistical difference when we compared the values of TEWL palmar preoperatively with their respective values at one week , one month , six months and 12 months . The main side effect observed was compensatory hyperhidrosis ( CH ) , which was most frequent in G3 after 12 months of follow-up . There was an improvement in QoL since the first evaluation of the postoperative period with no difference between groups . Both techniques were effective in the treatment of PH , generating objective reduction of TEWL regardless of the ganglion operated . Sympathectomy G3 had a higher incidence of CH , yet the improvement in QoL was similar in both groups BACKGROUND Thoracoscopic sympathicotomy is highly effective in treating disabling palmar hyperhidrosis . The ideal level to maximize efficacy and minimize the side effect of compensatory hyperhidrosis ( CH ) is controversial . This study compared sympathicotomy over the second ( R2 ) vs third ( R3 ) costal head relative to these variables in patients with massive palmar hyperhidrosis . METHODS This prospect i ve , r and omized study enrolled 121 patients with disabling palmoplantar hyperhidrosis assigned to bilateral sympathicotomy ( sympathetic transection ) , which was done over R2 in 61 ( n = 122 extremities ) or R3 in 60 ( n = 120 extremities ) . Patients were question ed at 6 months and at 1 year or more to assess efficacy , side effects , and satisfaction with the procedure . RESULTS Sympathicotomy at R2 failed to cure palmar hyperhidrosis in 5 of 122 ( 4.1 % ) extremities , but only 2 ( 1.6 % ) were to a truly profound dripping level of recurrence .  Sympathicotomy at R3 failed to cure palmar hyperhidrosis in 5 of 120 extremities ( 4.2 % ) , and all were dramatic failures with dripping recurrent sweating . The patients whose palmar hyperhidrosis was not completely cured were aged 19.7 ± 2.5 vs 26.4 ± 8.0 years ( p = 0.04 ) . Two R3 patients with failure underwent three redo R2 sympathicotomies , with curative results . R2 patients showed a trend toward a higher level of CH vs R3 patients at 6 months and after 1 year . The CH severity scale was 4.7 ± 2.7 ( n = 38 ) for R2 vs 3.8 ± 2.8 ( n = 36 ) for R3 ( p = NS ) at 6 months and 4.7 ± 2.5 ( n = 43 ) for R2 vs 3.7 ± 2.8 ( n = 37 ) for R3 ( p = NS ) after 1 year . Younger age , male sex , and higher levels of preoperative and postoperative plantar sweating were predictors of failed sympathicotomy . Increased age was associated with increased CH . CONCLUSIONS R2 and R3 sympathicotomy for massive palmoplantar hyperhidrosis are highly effective , with low recurrence and incidences of severe CH . R2 tends to have a higher level of CH vs R3 , and a higher incidence of dramatic failures is suggested in R3 patients , for which reoperation at the R2 level will likely be curative OBJECTIVE Endoscopic thoracic sympathetic surgery was effective for palmar hyperhidrosis ( PH ) , but side effects such as compensatory sweating and over dry h and s were common . A multiple centers prospect i ve r and omized study was design ed to compare the efficiency and side effects of T3 and T4 sympathicotomy in the treatment of PH . METHODS From September 2004 to February 2006 , 141 consecutive patients with PH were r and omized into two therapeutic groups : group T3 underwent T3 sympathicotomy ( n=68 ) and group T4 underwent T4 sympathicotomy ( n=73 ) . Improvement of h and sweating , side effects like compensatory sweating or over dry h and s , and satisfactory rate of the patients were recorded . RESULTS There were 78 males and 63 females . The median age was 26.9 years . The two groups were comparable in gender , age , severity of sweating and average period of follow-up . All operations were successful with no severe complications or perioperative mortality . A 17.8+/-7.9 month follow-up showed that palmar sweating improved in all patients and the effective rate was 100 % . Mild moist h and s occurred more frequent in group T4 than in group T3 ( 59.4 % vs 25.8 % , p<0.0001 ) . Most involved patients were ' very satisfied ' with this result except for four patients ( 5.8 % ) in group T4 ; incidences of compensatory sweating and over dry h and s were both lower in group T4 than in group T3 ( 56.5 % vs 77.4 % , p=0.011 and 1.4 % vs 12.9 % , p=0.013 , respectively ) . Moderate compensatory sweating ( CS ) occurred in 14.5 % in group T3 and 2.9 % in group T4 ( p=0.017 ) . ' Very satisfied ' rate was higher in group T4 than in group T3 ( p<0.0001 ) while ' partially satisfied ' rate was comparable between the two groups . CONCLUSION T3 and T4 sympathicotomies are both effective for the treatment of PH . T4 sympathicotomy , decreases the side effects but do not compromise the therapeutic effects , and should be the method of choice 
    Output:
    
No significant differences were found in symptom resolution and recurrence .
T4 TS appears to be more useful than T3 or T2 TS for PH