Osteoid osteoma of the second metatarsal bone diagnosed on MRI: A case report and literature review

Osteoid osteoma is a relatively common benign bone tumor that is most frequently seen on the appendicular skeleton in adolescents and young adults. Here we present the case of a 14-year-old boy presenting with a 10 month history of pain in his left foot which had been misdiagnosed as stress fracture due to its unusual clinical presentation. Magnetic resonance imaging of the left foot revealed a bone lesion with typical features of the osteoid osteoma on the distal part of the second metatarsal bone. The lesion was surgically removed and the diagnosis of osteoid osteoma was confirmed by post-surgical histopathologic examination of the resected section. The patient reported a substantial relief in his pain 4 weeks following the surgical operation.

Application of knee MRI in forensic age estimation: A retrospective cohort

INTRODUCTION

Forensic age estimation is performed via clinical examination and utilizing various imaging modalities. Currently, radiography and CT are used. In this study we aim to evaluate if magnetic resonance imaging (MRI) can be used to determine stages of fusion in the epiphysis of the tibia and femur, and if these stages are significantly different regarding the mean age of subjects classified in each one.

METHODS

A total of 193 subjects were included in the study. Knee MR imaging was performed on all of the patients, and the patients were categorized based on imaging findings of the tibial and femoral epiphysis. Tukey multiple comparison test and analysis of variance were used to assess if the difference in the mean age of the groups were significantly different.

RESULTS

Analysis of variance revealed that the mean of the five groups, both in tibia and femur imaging were significantly different. Analysis of variance showed that in most of the cases, the groups mean age significantly differed from the other groups. Tukey multiple comparison tests showed that although the differences between stages I-III could not be regarded as significant, MR imaging was suitable in distinguishing stages IV-V from stages I-III.

CONCLUSION

MR imaging of the knee may be a suitable imaging modality to assess an individual's age, does not involve ionizing radiation, and that with imaging a single anatomical location, at least two epiphyses could be used to determine the age.

IMPLICATIONS FOR PRACTICE

Utilization of knee MRI by clinicians as a safe and practical age estimation method.

Clinical and histopathological outcome of cervical and chest MRI involving non-MRI-conditional cardiac pacemakers: a study using sheep models

AIM

To examine the clinical and histopathological consequences of MRI in sheep implanted with non-MRI-conditional cardiac pacemakers.

MATERIALS AND METHODS

Under general anesthesia, active fixation leads of two dual-chamber, non-MRI-conditional cardiac pacemakers (St. Jude Medical and Medtronic) were implanted either at the right ventricular apex or at the right atrium of two male sheep and connected to the V and A channels of the pacemakers, respectively. The generators were placed in cervical subcutaneous pockets. On day 5, both sheep underwent 1.5 T cervical and chest MRI with continuous electrocardiogram monitoring. Obtained sequences were T1-weighted (T1W), T2-weighted (T2W), T2-gradient echo and diffusion weighted (DW). The employed modes were OVO, VOO and VVI for one sheep and OAO, AOO and AAI for the other (unipolar and bipolar configuration of pacing and sensing for both). Battery impedance, pacing lead impedance, intrinsic amplitude and capture thresholds were checked at baseline and after each sequence, as well as 48 h after imaging. Histopathological examination of the cardiac tissue around the lead tip was performed 4 weeks post-imaging.

RESULTS

No significant changes in device position or configuration were observed during or after MRI. Clinical outcome was uneventful in both sheep. Minor inflammatory and necrotic changes were reported after histopathological examination of the cardiac tissue around the lead tip.

CONCLUSION

1.5 T MRI of two implanted non-MRI-conditional pacemakers was found safe in terms of device configuration and stability, clinical outcome and cardiac tissue histopathological findings.

Diffusion-weighted magnetic resonance imaging in differentiating acute infectious spondylitis from degenerative Modic type 1 change; the role of b-value, apparent diffusion coefficient, claw sign and amorphous increased signal

OBJECTIVE

To examine the effect of using different b-values on the utility of diffusion-weighted (DW) MRI in differentiating acute infectious spondylitis from Modic type 1 and the discriminative accuracy of related apparent diffusion coefficient (ADC), claw-sign and amorphous increased signal.

METHODS

43 patients with equivocal diagnosis of acute infectious spondylitis/Modic type 1 by using MR images were prospectively studied. The discriminative accuracy of DW MRI using three b-values of 50, 400, 800 s mm(-2), ADC, claw sign and amorphous increased signal was examined.

RESULTS

DW MRI differentiated infectious spondylitis from Modic type 1 change most accurately when a b-value of 800 s mm(-2) was chosen [sensitivity, 91.7%; specificity, 96.8%; positive-predictive value (PPV), 91.7%; negative-predictive value (NPV), 96.8%; and accuracy, 95.3%]. The optimal cut-off ADC value was 1.52 × 10(-3) mm(2) s(-1) (sensitivity, 91.7%; specificity, 100%; PPV, 100%; NPV, 96.9%; and accuracy, 97.7%). Best visualized at a b-value of 50 s mm(-2), claw sign (for degeneration) and amorphous increased signal (for infection) were 100% accurate.

CONCLUSION

Should DW MRI be used in differentiating acute infectious spondylitis from degeneration, large b-values are required. With low b-values, however, claw sign and amorphous increased signal are very accurate in this regard.

ADVANCES IN KNOWLEDGE

DW MRI using large b-values could be used in differentiating acute infectious spondylitis from Modic type I.

Assessment of Diagnostic Value of Sonography for Cryptorchidism

Cryptorchidism refers to the condition in which the testicle is not positioned in the base of the scrotum. The most important goal of diagnosing and managing the undescended testis is to place the testis in the scrotum to maximize its potential for spermatogenesis. This article provides a comprehensive concept of cryptorchidism, its diagnosis, and complications. This prospective study was performed to assess the value of sonography in the diagnosis of undescended testes. This prospective study was performed to evaluate 124 cases of cryptorchidism. In the authors’ survey, the sensitivity of sonography for determining cryptorchidism was 91%. The most common site of undescended testis was the inguinal canal, and the right undescended testis was localized more than the left undescended testis. The results were compatible with other studies. It was concluded that sonography is the safest, most noninvasive, and most valuable method of detection for undescended testes.

Association of the type of trauma, occurrence of bone bruise, fracture and joint effusion with the injury to the menisci and ligaments in MRI of knee trauma

BACKGROUND

magnetic resonance imaging (MRI) as a noninvasive diagnostic tool may help clinicians in the evaluation of injuries to menisci and ligaments.

PURPOSE

this study assessed the associations between type of trauma to knee joint, bone bruise, fracture and pathological joint effusion with injuries to menisci and ligaments of knee joint.

METHODS

we reviewed knee joint MRI of 175 patients aged less than 45 years old who were referred to MRI center of our University.

RESULTS

statistical analysis showed that tearing of medial meniscus (MM) is significantly more common in sport related trauma (p= 0.045) but tearing of medial collateral ligament (MCL) is significantly more common in non-sport related trauma (p= 0.005). Existence of bone bruise in knee MRI is negatively associated with tearing of medial meniscus (MM) (p=0.004) and positively associated with tearing of anterior cruciate ligament (ACL) (p=0.00047) and medial collateral ligament (MCL) (p = 0.0001). Existence of fracture is associated with decreased risk of the tearing of ACL and MM (p=0.04, p=0.001 respectively). Pathologic joint effusion is significantly more common in ACL and MCL tearing (p=0.0001, p=0.004 respectively).

CONCLUSIONS

as diagnostic clues, bone bruise, fracture and joint effusion may help radiologists for better assessment of injury to menisci and ligaments in MRI of patients with knee trauma.

Orientation of the facet joints in degenerative rotatory lumbar scoliosis: an MR study on 52 patients

BACKGROUND

Because of a degenerative component, degenerative rotatory scoliosis seems different from congenital and idiopathic subtypes of the disease. This study aims to examine the orientation of facet joints, as a known cause of degeneration, in patients with degenerative rotatory scoliosis.

METHODS

Lumbar magnetic resonance (MR) images and plain radiographs of 52 symptomatic patients (mean age, 50.17 years) with degenerative rotatory lumbar scoliosis (mean curve, 19.22 degrees) and 50 healthy individuals were reviewed. Facet joint angles in rotated segments and the minimum neural foramen width at all lumbar levels were measured by three observers and the average was recorded.

RESULTS

The maximum vertebral rotation was most frequent at L4-L5 (75 %), and the majority was of type I (84.6 %) according to the Nash-Moe classification. At all lumbar spinal levels the mean facet joint angles were significantly higher on the side of rotation (L2-L3, 57.92 degrees; L3-L4, 45.00 degrees; L4-L5, 43.88 degrees) compared to those on the contralateral side (L2-L3, 20.42 degrees; L3-L4, 15.48 degrees; L4-L5, 13.12 degrees) and in controls (L2-L3, 30.21 degrees; L3-L4, 40.81 degrees; L4-L5, 45.20 degrees) (p < 0.001 for all comparisons). The mean facet joint angle increased significantly from L4-L5 to L2-L3 in cases and reversely in controls. The mean minimum neural foramen width was 1.29 ± 0.85 mm on the side of rotation, 5.50 ± 1.09 mm on the contralateral side, and 6.78 ± 1.75 mm in controls (p < 0.001).

CONCLUSIONS

Substantial asymmetries and abnormal orientations in facet joints were documented in patients with degenerative rotatory lumbar scoliosis. Such asymmetries may adversely affect neural foramen width.

Fetal Nasal Bone Status In Iranian Women Undergoing First-Trimester Screening For Trisomy 21: A Review and an Observational Study

Background:

Failed visualization of the fetal nasal bone (NB) by ultrasound at 11 - 14 weeks of gestation is strongly associated with chromosomal abnormalities. Meanwhile, the incidence of the absent fetal NB in normal fetuses in the first trimester in mothers of different ethnic origins differs significantly. It is, therefore, important to assess ethnic variations in the first-trimester visualization of the fetal NB before introducing this marker into routine screening programs for aneuploidy.

Objectives:

The objectives of this study were to determine the NB length and the prevalence of the NB absence as well as calculating the likelihood ratio (LR) for the absence of the NB in normal fetuses of Iranian women undergoing first-trimester screening for trisomy 21.

Patients and Methods:

In 767 normal fetuses, the fetal profile was examined by ultrasound for the absence/presence of the NB. The NB length was also measured, and the LR for the NB absence was also determined.

Results:

The NB was absent in 2/767 (0.26%) of the fetuses. The mean length of the NB was 3.6 ± 0.69 mm for the fetuses of 11 - 14 weeks gestational age. The LR value of the absent NB was equal to 250 in the normal fetuses of the Iranian population living in the North-West provinces.

Conclusion:

The low prevalence of the NB absence in normal fetuses in the present study is compatible with the larger size of the NB in Iranian people compared to other communities. Meanwhile, the reference range of the NB length in normal Iranian fetuses was established so that basic data could be recorded for further studies regarding the absence or presence of the NB in screening for chromosomal abnormalities (Down syndrome) within the Iranian population.

Supine spinal magnetic resonance imaging with straightened lower extremities in spondylolisthesis: a comparison with the conventional technique

OBJECTIVES

To compare the degree of slip in spondylolisthesis on supine magnetic resonance (MR) images obtained with flexed and straightened lower extremities.

METHODS

Supine spinal MR studies were performed in 100 cases of symptomatic spondylolisthesis with flexed and then straightened lower extremities. The angle of lumbar lordosis (by Cobb's method) and the degree of slip (by Taillard's method) were compared between the two sets of images.

RESULTS

The mean angle of lumbar lordosis increased from 51.65±8.57° on MR images with flexed lower limbs to 57.39±9.05° on MR images with straightened lower limbs (p<0.001; mean percent increase: 11.51%). Similar change was also observed for the mean degree of slip (from 25.80±7.74% to 28.68±7.93%, p<0.001; mean percent increase: 12.60%). After MR imaging with straightened lower extremities 22 out of 54 initially grade I cases had grade II disease (p<0.001).

CONCLUSIONS

Supine magnetic resonance imaging with straightened lower extremities detects higher degree of slippage in symptomatic patients with spondylolisthesis compared to conventional MRI with flexed lower extremities.

Magnetic resonance imaging of Whipple's disease confined to the CNS presenting with multiple intracerebral mass lesions

We report a patient diagnosed with Whipple's disease (WD) who presented only with neurological symptoms. Neuroimaging (MRI) showed lesions with marked mass effect similar to infiltrative tumors, which were hypersignal on long TR and hyposignal on short TR images, located in several areas of the brain. In serial controls, lesions resolved with gliosis and atrophic changes as well as migration of active infiltrative-like lesions to new areas. MR findings of the brain WD are discussed, which confirmed by stereotactic brain biopsy. Familiarity with the range of possible MR imaging appearances of WD enables the radiologist to place WD more effectively on the differential diagnosis which motivates the clinician to consider both the diagnosis and early initiation of treatment; so, this may significantly impact outcome. Moreover, repeated MR investigations may serve as a valuable method to evaluate efficacy of treatment and long term follow-up of WD involving the CNS.

Visibility of different foreign bodies in the maxillofacial region using plain radiography, CT, MRI and ultrasonography: an in vitro study

OBJECTIVES

To compare the usefulness of four imaging modalities in visualizing various foreign bodies of different sizes.

METHODS

Foreign bodies of four sizes (0.5, 1, 2 and 3 mm) including metal, tooth, wood, plastic, stone, glass and graphite were embedded in six fresh sheep heads on bone surface between the corpus mandible and muscle, and inside the tongue muscle. A human dry skull served as an air-filled space. Plain radiography, CT, MRI and ultrasonography were used, and four skilled radiologists rated the findings individually.

RESULTS

All embedded foreign bodies except wood were best visualized using CT. Wood could only be detected using ultrasonography, and then only when fragments were >0.5 mm in size. Plain radiography and CT were almost equally accurate in visualizing metal and graphite. MRI was the least useful imaging technique.

CONCLUSIONS

In cases with suspected foreign bodies in the maxillofacial region, CT seems to be the optimal initial imaging study. Wood, however, could only be detected using ultrasonography.

Bilateral primary breast lymphoma in a teenage girl with multi-organ involvement

We present 16 years old girl with primary breast lymphoma involving the both breasts simultaneously and co-incidence of central nervous system (CNS) involvement which originated from the breast, in addition to evidence of lymphoma in multi-organ such as skin, mediastinum and some abdominal viscera. Bilaterality has been observed in some series, but reports are few and series are often very small. Radiologic features may be indistinguishable from those of the other breast malignancies, but it can be concluded that primary involvement of the breast with lymphoma should be considered when breast mass or inflammatory changes occur in a patient without any previously diagnosed lymphoma. The clinical behavior, imaging and therapeutic procedures are discussed. The findings of this report may have clinical impact on oncologists or that may alter the disease concept of bilateral breast lymphoma.

Association between obstetric conjugate diameter measured by transabdominal ultrasonography during pregnancy and the type of delivery

Background

Normal morphological features of the maternal pelvis are an important prerequisite to vaginal delivery.

Objectives

We aimed to evaluate the association between obstetric conjugate diameter (OCD) measured by ultrasonography and the type of delivery, vaginally (V) or by cesarean (C) section.

Patients and Methods

Pelvimetry was performed in 200 primigravid women for fetal cephalic presentation. The OCD was measured twice by transabdominal ultrasonography during 25-30 weeks and 30-35 weeks of pregnancy.

Results

The mean OCD of both sonographies in groups V and C was 125.51± 8.35 mm (105-144.5) and 112.99 ± 8.53 mm (96-134.5), respectively, which was significantly lower in group C (P<0.001). The values of OCD between the first and second measurements were not different significantly (P=0.065). C-section was indicated in 65 (32.5%) mothers. The optimal cut-off point for the OCD in the prediction of vaginal delivery was ≥ 119.75 mm, with a sensitivity and specificity of 80% and 78.5%, respectively.

Conclusion

The US measurement of OCD might be an accurate method that almost always remains constant during late pregnancy; it is easy to measure and might be confidentially employed for predicting C-section, but needs more precise studies to be used widely.

Comparison of maximum signal intensity of contrast agent on t1-weighted images using spin echo, fast spin echo and inversion recovery sequences

Background

MRI is not able to directly measure the concentration of contrast agent. It is measured indirectly from the signal intensity (SI). It is very important to know how much contrast agent should be injected to receive a maximum SI in the region of interest (ROI).

Objectives

The aim of this study was to investigate the maximum relationship between contrast concentration and signal intensity (SI) on T1-weighted images using spin echo (SE), fast spin echo (FSE) and inversion recovery (IR) sequences.

Materials and Methods

To assess the relationship between SI and concentration, a water-filled phantom containing vials of different concentrations of gadolinium DTPA (Gd-DTPA) (0 to 19.77 mmol/L) or a constant concentration (1.2 mmol/L) of contrast agent was used. The vials of constant concentration were used to measure coil nonuniformity. The mean SI was obtained in the ROI using T1-weighted images. All studies were carried out using a 0.3 T clinical MR scanner with a standard head coil.

Results

This study shows that maximum SI will appear at different ranges in different sequences. The maximum SI can be seen at concentrations of 5.95, 4.96 and 3.98mmol/L for SE, FSE and IR, respectively.

Conclusion

Using standard imaging parameters, each MRI sequence reaches its maximum SI in a specific contrast concentration, which is highest in SE and least in IR in a comparison between SE, FSE and IR sequences.

Extramedullary plasmacytoma presenting as a solitary mass in the intracranial posterior fossa

A patient with a 3-month history of headache refractory to pain medication was admitted. The CT scan and MRI showed evidence of a posterior fossa mass. This was pathologically confirmed as an extra medullary plasmacytoma (EMP). He had a pathologic fracture of the left humerus 7 years ago while the radiologist was unaware at the time of diagnosis. A solitary bone plasmacytoma (SBP) was the cause of the pathologic fracture. This report includes the first description of MRI findings in a patient with a rare-incidence intracranial solitary extra medullary plasmacytoma (SEP) in Iran. There is a striking similarity between the features of intracranial SEP and meningiomas. Intracranial SEP, although rare, should be included in the differential diagnosis of brain tumors in areas where meningiomas commonly arise. The MRI findings and differential diagnosis of plasmacytoma are reviewed. Before this case report, only few cases have been reported in the literature. Nonetheless, this is the first report of posterior fossa EMP from Iran.

Diagnostic value of ultrasonography and magnetic resonance imaging in ulnar neuropathy at the elbow

Aim. To evaluate the diagnostic value of ultrasonography and magnetic resonance imaging (MRI) in patients with ulnar neuropathy at the elbow (UNE). Methods. We prospectively performed electrodiagnostic, ultrasonographic, and MRI studies in UNE patients and healthy controls. Three cross-sectional area (CSA) measurements of the ulnar nerve at multiple levels along the arm and maximum CSA(-max) were recorded. Results. The ulnar nerve CSA measurements were different between the UNE severity grades (P < 0.05). CSA-max had the greatest sensitivity (93%) and specificity (68%). Moreover, CSA-max ≥10 mm² defined the severe UNE cases (sensitivity/specificity: 82%/72%). In MRI, ulnar nerve hyperintensity had the greatest sensitivity (90%) and specificity (80%). Conclusion. Ultrasonography using CSA-max is sensitive and specific in UNE diagnosis and discriminating the severe UNE cases. Furthermore, MRI particularly targeting at increased signal of the ulnar nerve can be a useful diagnostic test of UNE.

Thrombolytic therapy for cerebral vein thrombosis in antiphospholipid syndrome secondary to systemic lupus erythematosus

A 20-year-old woman was admitted to a Gynecology Hospital in her 6(th) month of pregnancy for high blood pressure and tonic-clonic seizure. Primary diagnosis was eclampsia, and for that reason she underwent cesarean section. She also had headache on frontal and parietal areas without nausea or vomiting. There was not a focal neurological sign. Rheumatology consultation was requested. Systemic lupus erythematosus and secondary antiphospholipid (APS) was confirmed. The patient had headache that continued several days after cesarean section, therefore, brain magnetic resonance imaging (MRI) and magnetic resonance venography (MRV) were performed, and cerebral vein thrombosis was documented. Distal segment of right lateral sinus and sigmoid sinus were not appeared in brain MRV. Abnormal hypersignal intensity of right lateral sinus/coronal T2 was detected. Thrombolytic therapy with 20 mg tissue plasminogen activator on right sigmoid and transverse sinus was performed by an interventional neurologist. After this procedure, the patient(')s headache healed and she was discharged in a good condition.

Intracranial physiological calcifications in adults on computed tomography in Tabriz, Iran

Intracranial physiological calcifications are unaccompanied by any evidence of disease and have no demonstrable pathological cause. They are often due to calcium and sometimes iron deposition in the blood vessels of different structures of the brain. Computed tomography (CT) is the most sensitive means of detection of these calcifications. The aim of this study was the assessment of intracranial physiological calcifications in adults. We studied 1569 cases ranging in age from 15 to 85 in Tabriz Imam Khomeini Hospital, Iran. These patients had a history of head trauma and their CT scan did not show any evidence of pathological findings. The structures evaluated consisted of (A) the pineal gland, (B) the choroid plexus, (C) the habenula, (D) the basal ganglia, (E) the tentorium cerebelli, sagittal sinus and falx cerebri, (F) vessels and (G) lens and other structures which could be calcified. Of the 1569 subjects, 71.0% had pineal calcification, 66.2% had choroid plexus calcification, 20.1% had habenular calcification, 7.3% had tentorium cerebelli, sagittal sinus or falx cerebri calcifications, 6.6% had vascular calcification, 0.8% had basal ganglia calcification and 0.9% had lens and other non-defined calcifications. In general, the frequency of intracranial physiological calcifications was greater in men than in women. All types of calcification increased at older ages except for lens and other non-defined calcifications. We evaluated all the cranial structures and determined percentages for all types of intracranial physiological calcification. These statistics can be used for comparing physiological and pathological intracranial calcifications. Moreover, these statistics may be of interest from the clinical perspective and are potentially of clinical use.