ABSTRACT
Background: Carotid plaques contribute a significant cause of stroke and transient ischemic attacks together with long term disability worldwide. About 20-30% of cerebral infarction has been correlated with carotid atherosclerotic plaque and artery stenosis. The characterization of carotid artery plaque presents an opportunity to quantify patients with risk of cerebrovascular events and may be used to improve the therapeutic decision-making process such as carotid endarterectomy or angioplasty or stent placement. This study attempted to evaluate the imaging characteristics of carotid plaques using ultrasonography with Magnetic Resonance Imaging correlation and predict the risk of plaque rupture based on plaque enhancement characteristics as a surrogate marker. Materials and methods: Aim of the study was to evaluate and compare morphological characteristics of carotid plaques with Doppler ultrasonography and MRI and to predict plaque enhancement characteristics on MRI as a potential surrogate marker for plaque rupture leading to recurrent strokes. The present study evaluated 113 patients (65 males and 48 females) with stroke and transient ischemic attacks with ultrasound documented carotid plaques. These cases underwent Doppler evaluation of the carotid plaques and contrast enhanced MRI on the same day. The plaque morphology was evaluated both in the longitudinal as well as the transverse axis, and the stenosis was calculated based on the pulsed- wave Doppler evaluation of blood flow velocity as well as the area and diameter of the stenosis together with the signal and enhancement characteristics of the carotid plaques on MRI. The carotid artery at the region of maximal intimal thickness was evaluated for maximal area stenosis and diameter stenosis. The area stenosis was calculated as percentage stenosis in axial sections at the site of maximal thickness of the plaque. Results: The maximum incidence of carotid plaques was noted in the 61-80 years age group. The incidence was maximal at 71-80 years of age. Out of the 113 lesions, 65 (57.5%) were in men and 48 (42.4%) were in women. 44(38.9%) lesions were in patients who presented with TIA, while 69 (61.06%) presented with Ischemic stroke. 67 (59.29%) lesions were found on the left side and 46 (40.7%) on the right side. 67(59.3 %) lesions were found in the carotid bulb. The intimal thickness ranged from 1.1 mm to 5.6 mm with a mean of 2.97 mm. The range of stenosis was from 0% to 100%. Heterogeneous plaques were associated with symptomatic lesions in 76.2 % and homogeneous plaques were seen in 23.8%. The incidence of plaque calcification was inversely proportional to symptomatic plaques. Only 47.2 % of patients showed concordance between US and MRI with regard to homogeneity of the plaque. T2 weighted MR imaging of exvivo atherosclerotic plaques aided in the detection and evaluation of fibrous caps. 39 (34.1%) patients were given a gadolinium-based contrast agents, out of which 19 (48.7 %) did not show enhancement and 20 (51.2%) showed enhancement of the carotid plaque tissue. Doppler showed abnormalities in 29 patients (61.7%), whereas in MRA it is 18 patients (38.2 %), p value = < 0.004* in cases with less than 50% stenosis (n=47). In cases with 50-69% stenosis (n=29), doppler showed abnormalities in 19 patients (65.5%) whereas in MRA it was (34.4 %); P value was 0.431, The difference was not found to be statistically significant. While as in cases with 70-90% stenosis (n=37), MRA showed abnormalities in 25 patients (67.5%) whereas Doppler showed it in 12 (32.4%); P value was 0.017. Calcification was seen in 22 patients which appeared as hypointense focus on T1, T2, and TOF images. The heterogeneous lesions were better visualized on ultrasound compared to MRI. Conclusion: Ultrasound is a more sensitive modality than MRI for plaque size < 1.5 mm and a better tool in assessing the plaque characteristics when the area of stenosis is less than 50%. Hence, ultrasound is better as a screening tool. The homogenous lesions on ultrasound appeared homogenous on MRI with the plaque content of fat. The heterogeneous plaque on ultrasound, however, did not correlate with MRI. Enhancement of carotid plaque tissue, which implies vascular wall inflammation, is a marker of vulnerable plaque. MRA has a better discriminatory power compared with duplex ultrasonography in detecting 70-90% stenosis
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Background: An accidently ingested foreign body may get lodged within the lumen of gastrointestinal tract, pass uneventfully with feces or may migrate extraluminally into the surrounding tissues in which case it may lead to suppurative or vascular complications. The aim of the endeavor was to study the spectrum of imaging findings in patients with accidental ingestion of foreign bodies with trans-gastric migration of metallic foreign bodies.Methods: Total 33 patients with history of accidental ingestion of foreign bodies were subjected to preliminary radiograph of neck, chest and abdomen followed by upper gastrointestinal endoscopy. Failure to retrieve/ localize foreign body endoscopically from upper gastrointestinal tract with check radiograph reiterating the presence of foreign body in upper abdomen were subjected to computed tomography of abdomen.Results: A total of 33 patients comprising of 27 females and 6 males with mean age of 23.76 years with history of foreign body ingestion were studied. Ingested foreign bodies were lodged in pharynx (n=7), esophagus (n=3), stomach (n=13) or duodenum (n=3). In 7 patients in whom endoscopy failed to locate and/or retrieve foreign body, computed tomography confirmed the presence of trans-gastrically migrated foreign body in the surrounding structures. The location of migrated foreign bodies was in lesser sac (n = 2), greater omentum (n = 3), lesser omentum (n = 1) and transmural (n = 1). Two patients had evidence of collection formation around the migrated foreign bodies.Conclusions: Sharp or pointed metallic foreign bodies may migrate trans-luminally with various implications. Though radiography is the preliminary workhorse for the confirmation of ingested foreign bodies, computed tomography owing to its volumetric data acquisition helps in exact localization of migrated foreign bodies and should precede any therapeutic intervention for retrieval of migrated foreign bodies.
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Background: PACS (Picture archiving and communication systems) and digital imaging (DI) has revolutionized radiology bringing about a paradigm shift in the way radiodiagnosis is perceived and practiced with a slew of benefits like elimination of the need for manual handling of films, helping in long term storage of digital images, easy transfer and retrieval of radiographic images. The objective of this study was to analyse the influence of PACS and digital imaging on the workflow in the radiology, performance of the radiographer and image storage and retrieval capabilities.Methods: It was a questionnaire-based study in which questions were asked to the radiographers working in our hospital at five different working sites. Each questionnaire was aimed to evaluate the effect of digital imaging on radiology workflow, improvement in the performance of radiographers, reduction in the work-related frustration levels due to use of digital imaging and finally the utility of digital imaging in image storage, query and retrieval.Results: Among the 50 questionnaires 41 were completed and retrieved. Among the respondents, 90.24% indicated that digital imaging has obviated the need for repeat examinations, 95.12% agreed with the fact that it resulted in the reduction of the number of reject images, 95.1% said it helped them in improving their performances, 92.6% of the respondents said they did not face any issue with its use and 95.1% of the participants agreed that the image query and retrieval could be accomplished in a hassle-free manner.Conclusions: The digital imaging technique not only improves the performance of the radiographers but also increases the workflow of the health care hospitals or clinics. The digital imaging reduces the number of rejected images thus reducing radiation exposure to the patients. Further, it is highly cost-effective and time-saving.
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Background:Radiological determination of gender relies predominantly on the skeletal radiology and assumes importance in mass natural disasters, bomb explosions, exhumations and warfare where skeletal fragmentation is common. Varied literature is present regarding the role of foramen magnum in establishing gender identification.The objective of the study wasto establish normative values of cross-sectional area of foramen magnum in both genders using NCCT and try to ascertain any significant difference in cross-sectional area in the two genders which may help in gender identification.Methods:NCCT head images of 378 subjects were analysed in individuals beyond the age of skeletal immaturity. Free ROI technique using electronic calliper tool was used. The cross-sectional area of foramen magnum was automatically obtained after tracing its whole inner circumference.Results:Mean cross-sectional area of foramen magnum in females was 806.79±106.58 mm2and was 878.33±98.42 mm2in males. Although the cross-sectional area in males was greater than females no statistically significant difference was found. The correlation coefficient was found to be weaker (R=0.0413). Conclusions: No statistically significant difference was found between the two genders. The correlation coefficient was also weak to draw any inference about the gender of the skull on CT imaging. Further studies are needed to include other parameters like the sagittal and transverse diameters of foramen magnum in a larger sample to show importance of foramen magnum, if any, in helping gender identification of skeletal remains
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Background: Ultrasonography (USG) is a cheap, easily available and painless modality for the diagnosis of carpal tunnel syndrome. However, the main sonographic criteria of cross sectional area (CSA) and flattening ratio (FR) of median nerve show a wide normal variation which warrants establishment of normal range of variability in the dimensions of median nerve in different populations. Objective: The main aim of this study was to calculate the mean cross sectional area (CSA) and flattening ratio (FR) of median nerve at wrist in asymptomatic adults. Materials and methods: This prospective observational study included asymptomatic adults visiting our tertiary care hospital for unrelated heath conditions with no symptoms to suggest carpal tunnel syndrome. Ultrasound examination of both wrists was carried out by high frequency linear array transducer with frequency of 10MHz with the arm in supine neutral position on LOGIQ P5 (GE Healthcare, Chicago, Illinois, USA) ultrasound machine. The cross-sectional area (CSA) and flattening ratio (FR) of the median nerve was measured at the level of carpal tunnel inlet and mean values with standard deviation were calculated. Results: Three hundred seventy six (376) wrists of 188 subjects were examined. 36 wrists were excluded owing to presence of anatomic variations of the median nerve in them. 340 wrists of 170 patients were included in the study. Mean cross sectional area of median nerve was 9.2 mm2 (±1.2). Arshed Hussain Parry, Abdul Haseeb Wani, Naseer Ahmad Choh, Tariq Ahmad Gojwari. High-resolution ultrasonography measurement of dimensions of median nerve at wrist in asymptomatic adults. IAIM, 2019; 6(4): 144-149. Page 145 Mean value of flattening ratio was 2.4 (±0.6). Mean CSA (9.26 ±1.2 mm2 ) and FR (2.41 ±0.6) of males was not significantly different from mean CSA (9.16 ±1.2 mm2 ) and FR (2.4±0.55) of females. However, mean CSA of right wrist (9.4 ±1.2 mm2 ) was significantly different from mean CSA of left wrist (9.10 ±1.1 mm2 ). Conclusion: We found a higher mean cross sectional area (CSA) of 9.2 mm2 of median nerve in our population. There was a significant difference in the cross sectional area of median nerve between right and left wrists. However, we did not find statistically significant difference in the CSA and FR between the males and females. Establishment of normative data for the dimensions of median nerve is essential for different populations given the wide range of variations in the dimensions of median nerve
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Background: An enormous number of artefacts are encountered in magnetic resonance imaging (MRI) which jeopardize the image quality. A comprehensive knowledge of the sources and the remedial measures needed is pivotal to enhance and optimize the image quality in magnetic resonance imaging (MRI). Objectives: The primary objectives of the study were to identify different MRI artefacts, to find the reason/cause of these artefacts and to find methods for correction of these artefacts. Materials and methods: This was a prospective study which included all the patients that were referred to our department for various MRI examinations. The study was carried at 1.5 tesla Magnetom Avanto Siemens, Germany. All the MRI examinations were performed by trained technologist in presence of an experienced radiologist. The MR images acquired were studied for the presence of any artefacts during the performance of MRI examination, the MR parameters at which the artefacts appeared and subsequently the remedial measures undertaken. Results: A total of 209 patients comprising 95 females and 114 males, referred to our department for MRI examinations of various body parts were studied. The commonest artefact observed was motion artefact in 43 (20.6%) patients followed by susceptibility artefact and aliasing artefact. Less common artefacts observed were chemical shift artefact, herring bone artefact, Gibb’s artefact, Moiré fringe artefact, zipper artefact and magic angle phenomenon. Arshed Hussain Parry, Abdul Haseeb Wani, Abdul Momin Jan, Tariq Ahmad Gojwari. Artefacts in magnetic resonance imaging (MRI) and their remedies. IAIM, 2019; 6(4): 122-130. Page 123 Conclusion: Thorough understanding of the sources of magnetic resonance imaging (MRI) artefacts and the mechanism of their production enables