***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 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Objective To evaluate the diagnostic value of the Inlet-to-outlet median nerve area ratio ( IOR ) in patients with clinical ly and electrophysiologically confirmed carpal tunnel syndrome ( CTS ) . Methods Forty-six wrists in 46 consecutive patients with clinical and electrodiagnostic evidence of CTS and forty-four wrists in 44 healthy volunteers were examined with ultrasonography .  The cross-sectional area ( CSA ) of the median nerve was measured at the carpal tunnel inlet ( the level of scaphoid-pisiform ) and outlet ( the level of the hook of the hamate ) , and the IOR was calculated for each wrist . Ultrasonography and electrodiagnostic tests were performed under blinded conditions . Electrodiagnostic testing combined with clinical symptoms were considered to be the gold st and ard test . Receiver operating characteristic ( ROC ) curves were used to evaluate the diagnostic value between the inlet CSA and IOR . Results The study population included 16 men and 30 women ( mean age , 45.3 years ; range , 18–83 years ) . The control population included 18 men and 26 women ( mean age , 50.4 years ; range , 18–79 years ) . The mean inlet CSA was 8.7 mm2 in healthy controls and 14.6mm2 in CTS group ( P<0.001 ) . The mean IOR in healthy volunteers ( 1.0 ) was smaller than that in patients ( 1.6 , P<0.001 ) . Receiver operating characteristic analysis revealed a diagnostic advantage to using the IOR rather than the inlet CSA ( P<0.01 ) . An IOR cutoff value of ≥ 1.3 would yield 93 % specificity and 91 % sensitivity in the diagnosis of CTS . Conclusion The IOR of median nerve area promises to be an effective means in the diagnosis of CTS . A large-scale , r and omized controlled trial is required to determine how and when this parameter will be used Objective The aims of this study were to compare electrodiagnostic ( EDX ) confirmation of clinical diagnosis of carpal tunnel syndrome ( CTS ) with ultrasonography ( US ) , using a new set of normal values taking wrist circumference of subjects into account , and to determine whether EDX examination can be replaced by US to confirm CTS . Design A prospect i ve cohort of 156 patients with idiopathic CTS underwent US and EDX studies . Upper levels of normal cross-sectional area of the median nerve were established by taking wrist circumference into account and using linear regression equations . Results Of the selected patients , 83.3 % met the EDX criteria for CTS . The findings from the US were normal in 67 ( 42.9 % ) of 156 patients , and within this group , the findings from the EDX were abnormal in 44 patients ( 65.7 % ) . Of 89 patients with abnormal findings from the US , only 3 patients had normal findings from the EDX . Conclusions US can not replace EDX for confirmation of clinical diagnosis of CTS . However , an abnormal US test result has a high positive predictive value for abnormal EDX result in clinical ly defined CTS . US might reveal relevant anatomic information preoperatively that rarely has a direct influence on treatment management of patients with CTS . US testing , taking morphometric data into account , does not have the same diagnostic value as EDX does in confirming CTS Introduction . This study compares anatomical findings at wrist level in patients with known carpal tunnel syndrome ( CTS ) and controls by ultrasonography ( US ) . Material and Methods . Wrist-US investigations of 28 consecutive patients with 38 diagnosed , idiopathic CTS were compared to 49 healthy volunteers without history of CTS . Internal wrists dimensions , the presence of flexor muscle bellies in the carpal tunnel , and cross-sectional area of the median nerve were analyzed . The findings were correlated to gender , age , and BMI . Results . US demonstrated a square internal carpal tunnel configuration in CTS patients compared to controls ( P < 0.001 ) . Patients with CTS showed a trend towards the presence of flexor muscles bellies in the carpal tunnel ( odds ratio 1.77 , 95 % CI 0.337–8.33 ) . CTS was present in women with  higher BMI  ( P = 0.015 ) . Conclusion . US allowed detection of specific anatomical features at wrist level in CTS patients . This observation may enable — following confirmation in larger prospect i ve studies —risk evaluation for CTS development PURPOSE To determine whether sonography can be an alternative method to nerve conduction study ( NCS ) in the diagnosis of carpal tunnel syndrome ( CTS ) , by comparing sonography with nerve conduction study using clinical diagnosis as the reference st and ard . METHODS Forty-one wrists of 29 patients were enrolled , along with the same number of age- and gender-matched controls . All patients had sonographic measurement of the cross-sectional area ( CSA ) of the median nerve and NCS . Sensitivity and specificity were obtained and compared between sonography and NCS . RESULTS There were no significant differences in age , gender , body mass index and involved side between patients and controls ( p<.05 ) . The CSA at the tunnel inlet was significantly larger in patients than in controls ( p=.03 ) . The best cutoff value of CSA at the tunnel inlet was 10.7 mm(2 ) , which had a sensitivity of 66 % and a specificity of 63 % . NCS showed a sensitivity of 78 % and a specificity of 83 % . Sensitivity was similar between sonography and NCS ( p=0.27 ) , whereas specificity was significantly lower in sonography than in NCS ( p=0.02 ) . CONCLUSIONS Sonography is not accurate enough to replace NCS for the diagnosis of CTS . TYPE OF STUDY /LEVEL OF EVIDENCE Diagnostic III The utility of electrodiagnostic testing in the evaluation of carpal tunnel syndrome ( CTS ) has been question ed . We studied patients who met the clinical criteria for CTS and compared patients who had normal nerve conduction studies ( NCS ) with patients who had abnormal NCS . We found that 25 % of the CTS patients without confounding neurologic disorders had normal NCS with median palmar nerve stimulation .  Patients with abnormal NCS were older and heavier and had more clinical features of CTS . NCS results could not be predicted accurately from clinical features by use of logistic regression models . This was especially true in clinical ly borderline cases . NCS did not predict the outcome of conservative management . We concluded that NCS provide independent information in the evaluation of suspected CTS , especially when fewer clinical criteria are present , but that NCS are not helpful in predicting the outcome of nonsurgical management AIM The aim of study was to assess the usefulness of ultrasonographic measurements of the median nerve in the diagnosis of carpal tunnel syndrome . MATERIAL S AND METHODS Eighty-six patients with carpal tunnel syndrome confirmed by electromyography and 45 asymptomatic controls were included in the study and underwent high-resolution ultrasonography of the wrists . The cross-sectional area and flattening ratio at the level of the pisiform bone of the proximal carpal tunnel were measured . Data from the patient group and control group were compared to determine the statistical significance . The accuracy of the ultrasonographic diagnostic criteria for carpal tunnel syndrome was evaluated using receiver-operating characteristic ( ROC ) analysis . RESULTS One hundred and forty-eight wrists of 86 patients with carpal tunnel syndrome and 76 wrists of 45 control patients were examined . All measurements showed significant differences between patients and controls . Increased cross-sectional area of the median nerve was the most predictive measurement of carpal tunnel syndrome . Using the ROC curve , a cut-off value of > 10.5 mm2 at the level of pisiform bone provided a diagnostic sensitivity of 89 % and specificity of 94.7 % CONCLUSION The ultrasonographic measurement of the median nerve cross-sectional area is a sensitive , specific and useful non-invasive method for the diagnosis of carpal tunnel syndrome Keleş I , Kendi ATK , Aydın G , Zöğ ŞG , Orkun S : Diagnostic precision of ultrasonography in patients with carpal tunnel syndrome . Am J Phys Med Rehabil 2005;84:443–450 . Objective : To evaluate the diagnostic value of ultrasonography in patients with electrophysiologically confirmed carpal tunnel syndrome . Design : A prospect i ve  ultrasonographic study of 35 wrists with electrophysiologically confirmed carpal tunnel syndrome and of 40 normal wrists . Receiver-operating-characteristics curves for the ultrasonographic measurements of median nerve were plotted to identify the most optimal cutoff values . Results : The ultrasonographic measurements of median nerves were found to be increased significantly in patients with carpal tunnel syndrome when compared with controls , particularly in terms of cross-sectional area ( P < 0.001 ) and the bowing of the flexor retinaculum ( P < 0.01 ) but not in the flattening ratio ( P > 0.05 ) . According to receiver-operating-characteristics curve results , the most optimal cutoff value for the cross-sectional area of the median nerve was obtained at the level of middle carpal tunnel , which was 9.3 mm2 , with a sensitivity of 80 % and specificity of 77.5 % . The optimal cutoff value for the bowing of the flexor retinaculum was 3.7 mm , with a sensitivity of 71.4 % and specificity of 55 % . No optimum cutoff value could be identified from the receiver-operating-characteristics curves for the flattening ratio of median nerve . Conclusion : Ultrasonographic examination of the median nerve seems to be a promising method in the diagnosis of carpal tunnel syndrome , evaluating the morphologic changes of the median nerve in patients with clinical signs and symptoms . Further studies with wider series are needed to confirm our preliminary results 
    Output:
    
Conclusion There was an improved inter- and intra-rater reliability when external l and marks were used instead of sonographic l and marks