Shiraz University of Medical Sciences, Shiraz
Medical Imaging Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
Carpal Tunnel Syndrome (CTS) is the most common upper extremity impingement neuropathy caused by median nerve compression within the carpal tunnel due to various conditions such as bone abnormalities, inflammation, trauma, neoplastic lesions and endocrinopathies.
Increase in carpal tunnel pressure of more than 20 to 30 mmHg blocks the epineural blood flow, so the nerve function is damaged.
CTS is primarily a clinical diagnosis that is supported by electrodiagnostic studies, in recent years different imaging modalities, including MRI and ultrasound, have been suggested for diagnosis of CTS.
Materials and Methods:
During November 2011 till May 2013, 84 patients who were clinically suspicious for CTS were enrolled in our study (age of patients ranging from 19 to 66 years old with the average of 43years and sex ratio of female to male was 2.7: 1) .All of the patients underwent ecterodiagnostic tests (EDT) as the gold standard diagnostic modality and results of color Doppler sonography (CDS) were compared with electerodiagnostic findings.
According to the EDT, patients with positive results of CTS were divided into three groups of severity including; mild CTS with 9 patients(11%), moderate with14 cases (17%) and severe CTS with 18 patients (21%of total cases).Sensitivity of CDS for diagnosis of CTS was almost 83%, 71% and 55% in severe, moderate and mild cases of CTS respectively. Specificity of this imaging modality was determined near to 80% in three groups of the patients.
In addition to ecterodiagnostic tests, which are considered as the modality of choice for diagnosis of CTS, Doppler ultrasound can be a non-invasive imaging procedure for evaluation of patients that are clinically suspicious to this condition. Considering three groups of CTS based on severity of electerodiagnostic signs, results of CDS is more reliable in severe patients.