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  Background & Objectives: Cerebrovascular diseases are the most common disabiling neurologic disorders and the third cause of death in the population over 45 years of age. Most of the strokes in adults are ischemic and almost one-fifth of them are due to intra- or extracranial internal carotid artery stenosis. Ultrasonography is a noninvasive, cost-effective and safe technique for evaluation of intra or extracranial vessels that is available in two methods: TCD and carotid Duplex. The present research is an attempt to investigate the appropriatens and comprehensiveness of TCD in diagnosing symptomatic significant carotid stenosis.

  Methods : This descriptive-analytical study was conducted on fifty patients admitted to the neurology ward of Imam Hospital who underwent both carotid duplex and TCD examination. Variables of blood flow velocities, collateral flow evidences and degree of carotid stenosis were assessed with both methods. The data were analyzed by SPSS (ver.11.5) using T.test, Chi-square and Fisher test.

  Results : 34 patieuts were. Male mean age of the patients was 66.70% of the subjects were above 65 and 68% of them had a history of hypertension. No statistically significant difference was seen between systolic and diatolic blood flow velocity in internal carotid artery and pulsatile index obtnined from reported by TCD and carotid Duplex. There was no statistically significant difference between the percentage of stenosis TCD finding of the patients with carotid stenosis showed collateral flow in 78.57% of the cases.

  Conclusion: Acceptable correlation of the flow velocity parameters and the percentage of carotid stenosis between TCD and Carotid Duplex results showed that the primary performance of TCD to diagnose significant carotid stenosis (that causes hemodynamic disorder) and screen ischemic cerebrovascular accident is a reliable and effective method, but for precise determination of stenosis, plaque typing and for diagnosing stenisis below 50% the performance of carotid duplex study is also necessary and to complemantory TCD.

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Background & objectives: 10 year survival rates for thyroid cancer is about 90%, but papillary thyroid cancer often spread to regional lymph nodes resulting in survival rate falls below 90%. In patients with thyroid cancer, cervical lymph node metastasis risk is about 20 to 50 percent. The aim of this study was to evaluate the association between ultrasound results and the involvement of lymph nodes before thyroidectomy and compare it with the pathologic response after thyroidectomy in patients with non-medullary thyroid cancer.
Methods: 60 patients with thyroid cancer were randomly selected and entered into the study. Ultrasonographic examination of cervical lymph nodes was performed by two radiologists using an ultrasound machine in all patients diagnosed with thyroid cancer. Patients underwent total thyroidectomy and neck lymph node dissection by surgeon.
Results: In papillary thyroid cancer, there was a significant relationship between ultrasonographic results and pathologic outcomes in determining the presence of cervical lymph node metastasis before thyroidectomy. And also, there was a significant relationship between the results of ultrasonography and pathologic findings in determining the location of affected lymph nodes.
Conclusion: Compared to histological examination, ultrasonography can be a useful tool in determining the location of affected cervical lymph node in thyroid cancers before surgery.