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Background and Objective: Internal derangement of knee (IDK) is a common problem following knee trauma. Magnetic resonance imaging (MRI) extensively is used to diagnose the ligamentous and meniscal injuries, but the use of ultrasonography remains controversial. Previous studies showed different results about the usefulness of sonography (IDK). This study was done to determine diagnostic accuracy of ultrasonography in comparison with magnetic resonance imaging in patients with knee trauma. Materials and Methods: This descriptive study was done on internal knee disorders of 73 patients with knee trauma who referred to MRI center of Imam Khomeini hospital in Sari, Iran during 2009-10. Three radiologists independently reported the ultrasonography and MRI of the patients. Results: The study population comprised of 61 (83.6%) men and 12 (16.4%) women, 91.9% of patients were less than 40 years old. The joint pain was the most common complaint (89%). The sensitivity, specificity, positive and negative predictive value of ultrasonography for the lateral meniscus was 100%, 97.14%, 60%, 100%, for the medial meniscus were 61.90%, 94.23% ,81.25%, 85.96%, for the anterior cruciate ligament (ACL) was 65%, 100%, 100%, 70.21% and for the medial collateral ligament (MCL) was 100%, 94.28, %42.86 and 100%. Conclusion: This study showed that the high specificity of ultrasonography as a noninvasive and inexpensive method to exclude the ACL and meniscal lesion. Ultrasonography can reasonably be applied for screening of internal derangement of knee in the absence of MRI, especially in urgent conditions. In clinical setting of highly suspicious of ACL and meniscal tear, MRI is preferred due to low sensitivity of sonography.

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Background and Objective: Since accurate and quick clinical and paraclinical diagnostic methods are not available, in some cases diagnosis of active pulmonary tuberculosis occurs after considerable time from the onset of disease. This study was designed to determine the diagnostic value of High Resolution Computed Tomographic (HRCT) scan in active pulmonary tuberculosis, in Gorgan, Golestan province, North of Iran. Materials and Methods: This diagnostic screening study was carried out on 135 (79 male and 56 female) hospitalized patients suspected with active pulmonary tuberculosis, and HRCT was used in their course of treatment as recommendation of their clinician. The patients were chosen from 5th Azar hosptial during 2009-10. Also it should be mentioned that patients were selected on avaliabity bases, and they were examined by smear, and sputum culture. The patients with negative smear and culture were set up as true healthy group (64 subjects). The lung or small nuddles in HRCT was considered as proper position of lung involvument in active lung pulmonary. The HRCT findings between the case group (71 subjects) and healthy group were compared. According to HRCT findings, the sensitivity and specifity were determined for each patient. Data were analyzed using SPSS-16 and Chi-Square test. Results: In this study, sensitivity, specificity, positive predictive value and negative predictive value of HRCT in active pulmonary tuberculosis were equal to 97.2%, 71.9%, 79.3% and 95.8% respectively. Involvement of upper and middle lobe of the right lung and upper lobe of the left lung were significantly higher than the control group (P<0.05). Conclusion: This study showed that HRCT has high sensitivity and specificity in diagnosis of active pulmonary tuberculosis and can be used as a quick diagnostic way in active pulmonary tuberculosis, especially in patients with strong clinical suspicion and negative smear.

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Background and Objective: The exposures related to the department of radiology can be considered as harmful agent for human. This study was done to assess the partial distribution of the equivalent dose in radiology waiting room in Ardabil, Iran. Materials and Methods: This descriptive analytical study was done in the radiology department and related waiting rooms of 4 teaching hospital and 3 private radiology sonography centers in Ardabil, Northwest of Iran, during 2011. The variables including type of radiography, the number and condition, staying duration in waiting room were considered for dosimetry. Data were analyzed using SPSS-18 and Chi-Square test. Results: The lowest radiation dose belong to one specialist radiology sonography center with 0.2±0.002 µS.h^-1V, but for each radiography were determined to be 0.00275±0.004 µS.h^-1V. The highest radiation dose belong to one specialist radiography sonography center with 0.4±0.045 µS.h^-1V and for each radiography was 0.016±0.0006 µS.h^-1V. Two teaching hospitals accompanied with three privates centers showed to have radiation dose-rate higher than 0.3 µS.h^-1V (P<0.05). Conclusion: This study showed that the increasing radiation-dose rate (higher than 0.3 µS.h^-1V) in teaching hospitals and private centers can be related to either the unit life or inadepuate of radiological protective shield.

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Background and Objective: The vertebra is the most common site of bone metastases. Diagnosis of metastases particularly in the early stages can improve patients’ prognosis and therapy. This study was done to compare the diagnostic value of magnetic resonance imaging and bone scan for the diagnosis of vertebral metastases. Methods: This descriptive study was done on 43 patients with any types of primary cancer. Patients underwent spinal magnetic resonance imaging and nuclear scan. Bone scan results were considered as the gold standard. The sensitivity and specificity were calculated for magnetic resonance imaging and nuclear scan. Results: The magnetic resonance imaging diagnosed 19 cases of thoracic vertebral metastases which previously diagnosed as negative by bone scan. Sensitivity and specificity of magnetic resonance imaging compared to bone scan was 90.7% and 95.6%, respectively. The magnetic resonance imaging diagnosed 4 cases of lumbar vertebral metastases which were reported negative in bone scan. Sensitivity, specificity and accuracy of magnetic resonance imaging in compare to bone scan were 97.6%, 97% and 97.2%, respectively. Conclusion: In diagnosis of vertebral metastases, the magnetic resonance imaging is more sensitive than bone scan.

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Background and Objective: Cholelithiasis have concomitant with biliary tract stones (BTS) in about 10-15% of the affected patients. This study was carried out to compare the specificity and the sensitivity of ultrasonography and computed tomography (CT scan) with the endoscopic retrograde cholangio pancreatography (ERCP) for detecting of the biliary tract stones and to evaluate the efficacy of the ERCP therapy. Methods: In this descriptive study, 135 patients suspected of BTS whom were candidate for the ERCP were gone under investigation. Ultrasonography of the gallbladder, liver, biliary tract, oral and IV contrast of abdominal CT scan and the ERCP were conducted for each patient. ERCP was considered as key critria to define BTS. The specificity and sensitivity of the ultrasonography and CT scan and the success rate of the therapeutic ERCP was estimated. Results: BTS were observed in 112 patients by ERCP method. The specificity and sensitivity of the ultrasonography was 72.3% and 73.9%, respectively. The specificity and sensitivity of the CT scan was 50.8% and 91.3%, respectively. The success rate of the therapeutic ERCP was estimated as 76.9%. Conclusion: Ultrasonography as a non-invasive, non-expensive and well sensitivity method which is recommended in patient screening of biliary tract stones in compare to ERCP and CT scan.

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Background and Objective: Thyroid nodules are common among the general population and they increase the risk of thyroid malignancies. This study was done to evaluate the correlation of findings of ultrasound based on Thyroid Imaging and Reporting Data System (TIRADS) and cytology of fine needle aspiration (FNA) based on Bethesda system to evaluate of thyroid nodules.
Methods: This descriptive-analytical study, was performed on 165 patients (152 females and 13 males) referred to the sonography center of Sayyad Shirazi Educational Hospital, Gorgan, northern Iran during 2018. Ultralosonographic features of nodules were recorded in the pre-filled checklist. According to TIRADS and endocrinologist clinical suspicion, couple of patients was eligible for FNA under the ultrasound guidance. The cytology of FNAs was reported based on the Bethesda system classification.
Results: The mean age was significantly lower in patients with malignant nodules (35.4 vs 44.8; P<0.05). Frequency of malignancy was 8 times higher among females than males (16 vs. 2). TIRADS 3 and 4 were the most common categories among the others with the prevalence of 44.4% and 32.3%, respectively. Bethesda 2 and 4 were the most prevalent categories with prevalence of 58.8% and 20.6%, respectively. The strongest agreement was observed between TIRADS 2 and Bethesda 2 that showed benign findings. Kappa index was 0.061 between TIRADS and Bethesda (P<0.05). Echogenicity, echogenic foci, shape, and margin of nodules were seen significantly more in malignancy.
Conclusion: The most accurate prediction of TIRADS belongs to benign nodules. The correlation between TIRADS and Bethesda was evaluated to be significant overall and the maximum level of correlation was at benign findings. Therefore, these two systems can efficiently be used in order to rule out malignancies and reduce the rate of invasive interventions.

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Background and Objective: Intrauterine growth restriction (IUGR) is an obstetrical complication. IUGR increases the chance of neonatal death and obstetrical complications in comparison with normal pregnancy. Timely diagnosis of this condition allows effective interventions that decrease the morbidity and mortality. This study was done to compare of superior vena cava to aorta diameter ratio in three vessel view in fetuses with intrauterine growth restriction and normal growth fetuses.
Methods: This case control study was performed on 60 mothers in 25 to 37 weeks of pregnancy who were referred to radiology department of a hospital in Iran during 2018-19. 30 patients were diagnosed with IUGR and were included as case group. 30 healthy fetuses were included as control group. Routine ultrasonography was performed for evaluating placenta, fetuse, and amniotic fluid. Also, colour Doppler sonography was performed on umbilical vessels along with superior vena cava and ascending aorta for definite diagnosis of IUGR. Demographic data regarding fetuse’s age, pregnancy status, number of parities, and age of mother were also accumulated. The superior vena cava/aorta ratio (SVC/AO) was compared in IUGR and healthy fetuses. Based on their amniotic fluid, fetuses were divided into normal and mild oligohydramnios.
Results: There was a significant difference in SVC/AO diameter index between case and control groups (P<0.05). Mean SVC/AO ratio was significantly higher in IUGR fetuses in compared to healthy fetuses. There was no significant difference between normal and oligohydramnios fetuses either in case or control groups.
Conclusion: Implementation of SVC/AO diameter index in three vessels view sonography in screening programs for pregnant women can reduce neonatal morbidity and mortality.

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Understanding maxillary sinus hypoplasia (MSH) and associated sinonasal variants is crucial for the success of diagnostic and therapeutic procedures in maxillary sinus and maxillary dental implant surgery. The aim of this study was to investigate a rare case of unilateral maxillary sinus hypoplasia associated with lower orbital floor displacement, without involving the Uncinate process. A 31-year-old woman presented to the Department of Oral and Maxillofacial Surgery at Babol Dental School for rhinoplasty without any complaints of headache or nasal congestion. She had no history of trauma, congenital or bone diseases/abnormalities. Cone Beam Computed Tomography (CBCT) images revealed left maxillary sinus hypoplasia, lower orbital floor, and increased thickening of the sinus mucosa. The patient's photograph also showed lower displacement of the orbital floor. The diagnosis of unilateral maxillary sinus hypoplasia in this study was based on clinical manifestations and coronal views of CBCT and CT scans. Symptoms of hypoplastic sinus include chronic headache, facial pain, voice problems, or may sometimes be asymptomatic. If the surgeon is not aware of the hypoplasticity of the sinus, complications during surgery may increase, including post-surgery complications such as visibility of the low orbital floor and resulting patient confusion. This study highlights the importance of using CBCT as a valuable diagnostic tool to identify anatomical variations and details of the hypoplastic sinus. This approach helps the surgeon to inform the patient and provide an appropriate treatment plan, especially in cases involving dental implants or sinus surgery.
 

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Background and Objective: Sinus extension is a physiological process that occurs in the growth cells of the paranasal sinuses and leads to increasing their volume over time, causing challenges in the dental implant process. This study was conducted to evaluate maxillary sinus morphometrics by cone-beam computed tomography (CBCT).
Methods: This descriptive-analytical study was conducted on the CBCT images of 100 people (52 male and 48 female) with a mean age of 45.32 ± 17.41 and the age range of 27 to 63 years referring to an oral and maxillofacial specialized radiology clinic in Babol, Iran during 2019. The amount of maxillary sinus extension in the panoramic-like view was recorded based on the amount of its extension in terms of the first anterior tooth and the last posterior tooth. In the new net technologies (NNT) software, in the section related to creating panoramic-like views, first, in the axial sections, the starting point of the maxillary sinus was specified from the occlusal side, and the mediolateral dimensions were measured at distances of 3 mm above and 3 mm below.
Results: The highest amount of maxillary sinus progress in the right anterior side was related to the mesial of tooth 5 (15%), and the highest amount of sinus progress in the left anterior side was related to the distal of tooth 3 (15%) and the mesial of tooth 4 (15%), which had no statistically significant differences. The most progress in the anterior area was related to the distal of the canine tooth and the mesial of the first premolar. The mean mediolateral sinus progress at 3 mm above the right nasal floor was higher in females than in males (P<0.05). Gender and age had no statistically significant relationship with maxillary sinus progress.
Conclusion: The maxillary sinus progress was almost equal in the left and right sides and also in males and females.

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Background and Objective: The infraorbital canal (IOC) is located in the floor of the orbit and terminates at the infraorbital foramen below the orbital rim. The IOC is a crucial anatomical landmark for successful anesthesia in dentistry and oral and maxillofacial surgery. This study aimed to evaluate the position and dimensions of the IOC based on cone-beam computed tomography (CBCT).
Methods: This descriptive-analytical study was conducted on CBCT images of 250 individuals (105 males and 145 females) (mean age = 36.14±17.7 years) referring to a specialized oral and maxillofacial radiology clinic in Babol, Iran, during 2021-22. Three different types of IOC pathways from the sinus roof were measured: Completely located within the maxillary sinus roof (Type 1), located below the maxillary sinus roof (Type 2), and suspended from the maxillary sinus roof within the septum or lamella of the infraorbital ethmoid cell (Type 3). Additionally, the angles between the IOC and the infraorbital groove with the maxillary sinus roof, the angles between the IOC and the infraorbital groove, the lengths of the IOC and the infraorbital groove, and the distances of the IOC from various anatomical landmarks were measured. Distances of the IOC (mm) were evaluated from other anatomical landmarks according to gender and age groups.
Results: Overall, various pathways of the IOC from the sinus roof were 39.4% in Type 1, 53% in Type 2, and 7.6% in Type 3; the mean distance of the IOC to the infraorbital rim was 8.58±1.30 mm, and to the midpoint of the canine root was 10.16±0.81 mm. The mean length of the canal was 25.89±2.47 mm, and the infraorbital groove was 5.06±0.58 mm; and the mean angle between the IOC and the infraorbital groove was 153.20±3.28 degrees. In general, the distance of the IOC to the midpoint of the canine root on both the left and right sides was greater in males than in females, which was statistically significant on the left side (P<0.05). It was found that the length of the IOC and the angle between the IOC and the infraorbital groove on the left side had statistically significant correlations with age groups (P<0.05). The mean distance from the foramen to the infraorbital rim and the length of the IOC were proportional to the degree of nerve protrusion into the maxillary sinus; however, no significant correlation was found between the types of canals (degree of nerve protrusion) and gender.
Conclusion: Type 2 was the most common pathway of the IOC from the sinus roof. Although Type 3 was less common, due to the high risk associated with this type of canal, surgeons should be fully aware of the morphology and anatomical position of the IOC during sinus and orbital surgeries to reduce probable injuries.