Intravenous Administration Of Gadolinium Research Articles

T1 contrast versus fluid-attenuated inversion recovery contrast technique for evaluation of cerebral tuberculosis

Objectives: T2-weighted (T2W) fluid-attenuated inversion recovery (FLAIR), a traditional magnetic resonance imaging (MRI) technique, is regarded as one of the most effective methods for examining brain disorders. The identification of brain pathologies can be significantly aided by T2 FLAIR and T1 post-contrast imaging. However, lesion enhancement is occasionally inconspicuous on T1-weighted image. Hence, for the evaluation of brain disorders, a MRI approach known as FLAIR contrast would combine the benefits of T2W FLAIR with contrast-enhancement on a single picture. Material and Methods: After obtaining clearance from the Institution’s Ethics Committee, contrast-enhanced MRI (CE-MRI) brain of 20 patients was taken for the study. CE-MRI was performed using 1.5 Tesla Intera PHILIPS with intravenous administration of gadolinium at approximately 0.1 mL/kg/body at a rate of 10 mL/15 s. Results: This study showed a better appreciation of lesion conspicuity when compared to prior T1 contrast images. However, there was no significant difference in the number of lesions, lesion extension, and degree of contrast-enhancement on comparison with T1 contrast images. Conclusion: T1 FLAIR contrast shows a better appreciation of lesion conspicuity when compared to T1 contrast images. Post-contrast FLAIR imaging is a valuable adjunct to post-contrast T1W imaging and effectively delineates cerebral tubercular pathologies. However, T1 FLAIR cannot be used as a replacement for conventional T1 fat saturated post-contrast imaging.

Abstract TP89: Ldl Levels May Correlate With Intracranial Atherosclerotic Plaque Enhancement

Introduction: The enhancement of atherosclerotic plaques after the intravenous administration of gadolinium (Gd) has been correlated with the presence of culprit plaques in patients with acute strokes due to underlying intracranial atherosclerosis (ICAS). A new method to objectively quantify Gd-enhancement was used to monitor plaques over time after an acute stroke. Currently there is no imaging method to accurately monitor atherosclerotic activity. Methods: Patients with stroke or transient ischemic attack caused by ICAS were included. Every patient was started on high-dose statins after ictus. 7T MRI images were obtained at baseline and after at least 6 months. LDL levels were obtained at the time of the event and at follow-up. Culprit plaques were identified based on degree of stenosis, presence of positive remodeling and Gd-enhancement. Arterial 3D enhancement maps in the territory of the culprit plaque were generated. Orthogonal signal intensity (SI) probes were expanded into the plaque and parent vessel to generate 3D enhancement color maps. Arterial segment variance (ASV) (SD 2 Arterial segment Baseline T1+Gd - SD 2 Arterial segment Follow up T1+Gd ) was used to compare the plaque and parent vessel enhancement. Results: Five patients underwent baseline and follow-up imaging. The median time between scans was 13.3 (IQR=13.3) months. ASV was strongly correlated with changes in LDL (Rho=0.9, p=0.037). Additionally, Gd-enhancement and plaque burden correlated with levels of LDL (Figure): Gd uptake (Rho=0.7, p=0.22) and plaque burden (Rho=0.67, p=0.22). Conclusion: This pilot study demonstrates that high-resolution imaging can be used in determining the response to statins in patients with high atherosclerotic burden. Gd-enhancement and plaque burden correlated with serum values of LDL. 3D enhancement maps and histogram analysis of atherosclerotic plaques are promising tools for evaluating disease activity and response to medical therapy.

Longitudinal variation of endolymphatic hydrops in patients with Ménière's disease.

The relationships of endolymphatic hydrops (EH) and perilymphatic enhancement (PE) with Ménière's disease (MD) remains unclear. This study aimed to describe the dynamic variation of EH and PE for MD patients over 2 hospitalizations by applying magnetic resonance imaging (MRI) to further clarify the relationships of EH and PE with MD. A total of 77 MD patients who underwent inner ear MRI after intravenous administration of gadolinium and pure-tone average (PTA) testing during a first and second hospitalization were included. The degree of EH and PE were evaluated via MRI, and the duration and frequency of vertigo attacks and PTA were collected and recorded. The PTA, EH, and PE for the 2 hospitalizations were compared, and the relationships of EH and cochlear PE with the MD stage were investigated. There was no difference between the 2 hospitalizations for duration of vertigo attacks or frequency of vertigo attacks. However, there were significant differences in PTA (Z=-3.02, P=0.003). Additionally, the cochlear and vestibular EH in the asymptomatic ear at the second hospitalization was significantly worse than that of the first hospitalization (Z=-2.33 and -2.49, P=0.020 and 0.013, respectively), while there were no differences in EH and PE in the affected ear (all P>0.05). Moreover, the degree of cochlear and vestibular EH was correlated with MD stage (both P<0.01). Although EH and PE in the affected ear were unchanged over 2 hospitalizations, an underlying EH in the asymptomatic ear and hearing loss in the affected ear for MD patients developed longitudinally with the duration of disease, and EH varied with the natural course of MD whereas PE did not. Therefore, EH instead of PE is necessary but insufficient to cause the clinical symptoms of MD.

3D CRANI, a novel MR neurography sequence, can reliable visualise the extraforaminal cranial and occipital nerves

ObjectivesWe aim to validate 3D CRANI, a novel high-field STIR TSE, MR neurography sequence in the visualisation of the extraforaminal cranial and occipital nerve branches on a 3-T system. Furthermore, we wish to evaluate the role of gadolinium administration and calculate nerve benchmark values for future reference.MethodsEleven consecutive patients underwent MR imaging including the 3D CRANI sequence before and immediately after intravenous gadolinium administration. Two observers rated suppression quality and nerve visualisation using Likert scales before and after contrast administration. Extraforaminal cranial and occipital nerves were assessed. Nerve calibers and signal intensities were measured at predefined anatomical landmarks, and apparent signal intensity ratios were calculated.ResultsThe assessed segments of the cranial and occipital nerves could be identified in most cases. The overall intrarater agreement was 79.2% and interrater agreement was 82.7% (intrarater κ = .561, p < .0001; interrater κ = .642, p < .0001). After contrast administration, this significantly improved to an intrarater agreement of 92.7% and interrater agreement of 93.6% (intrarater κ = .688, p < .0001; interrater κ = .727, p < .0001).Contrast administration improved suppression quality and significant changes in nerve caliber and signal intensity measurements. Nerve diameter and signal intensity benchmarking values were obtained.Conclusion3D CRANI is reliable for the visualization of the extraforaminal cranial and occipital nerves. Intravenous gadolinium significantly improves MR neurography when applying this sequence. Benchmarking data are published to allow future assessment of the 3D CRANI sequence in patients with pathology of the extraforaminal cranial and occipital nerves.Key Points• MR neurography using the 3D CRANI sequence is a reliable method to evaluate the extraforaminal cranial and occipital nerves.• Gadolinium contrast administration significantly improves suppression quality and nerve visualisation.• Benchmarking values including apparent signal intensity ratios and nerve calibers depend on contrast administration and might play an important role in future studies evaluating extraforaminal cranial and occipital neuropathies.

Comparison of an optimized 3D-real IR and a 3D-FLAIR with a constant flip angle in the evaluation of endolymphatic hydrops

PurposeTo evaluate an optimized 3D-real IR sequence with a longer TR (16,000 ms) based on the modulated flip angle technique in refocused imaging with extended echo train (MATRIX) for the endolymphatic hydrops (EH) after intravenous (IV) single-dose gadolinium (Gd) administration, and compare it with a heavily T2-weighted 3D-FLAIR sequence with a constant flip angle. MethodThe 3D-FLAIR and 3D-real IR sequences were performed in forty patients with definite Meniere’s disease (MD) four hours after IV Gd administration. Image qualities of the two sequences were rated and compared. Contrast-to-noise ratios (CNRs) and signal-to-noise ratios (SNRs) of the two sequences were measured for quantitative comparison. EH was graded on the images of the two sequences by two radiologists. ResultsScores and CNRs of the 3D-real IR were significantly higher than those of the 3D-FLAIR (P < 0.05). SNRs of the two sequences were comparable between the two groups. 3D-real IR had a higher inter- and intra-observer reliability for the grading of cochlear and vestibular EH than 3D-FLAIR. Using 3D-real IR sequence, the detection rate of EH of the whole labyrinth was higher than using 3D-FLAIR (86.6 % vs 73.3 %, p = 0.031). In the patients with unilateral MD, SNRs in the affected sides were significantly higher than the unaffected sides (P < 0.05). ConclusionsThe optimized 3D-real IR with a longer TR is a robust sequence with an improved depiction of EH after IV administration of single-dose Gd. Compared with 3D-FLAIR, it may allow a more precise evaluation and grading of EH.

Cardiac magnetic resonance imaging and the myocardium : Differentiation between vital and nonvital tissue

Cardiac magnetic resonance (cMR), awell-established imaging tool, is indispensable in the diagnosis and management of cardiovascular disease. Given its high spatial resolution and ability to characterize tissue, cMR represents the gold standard in determining myocardial viability. Gadolinium-based contrast-enhanced cMR can accurately identify myocardial scars and fibrosis in the ventricle and the atria, and differentiate it from normal myocardium. Gadolinium is an extracellular molecule which has been shown to be safe and beneficial in magnetic resonance imaging (MRI). Due to the larger extracellular space in myocardial scars, there is more uptake (wash-in) and slower elimination (wash-out) of gadolinium in those areas as opposed to normal myocardium. When imaged several minutes after intravenous administration of gadolinium, nonviable myocardial areas appear brighter than viable myocardium. The use of late-gadolinium enhancement (LGE) technique in assessing myocardial viability has been shown to highly correlate with histological examinations. Furthermore, this technique is highly reproducible and has very high intra- and interobserver agreement. Extent of LGE after myocardial infarction predicts the occurrence of adverse cardiovascular events. Moreover, LGE is highly accurate in predicting functional recovery of dysfunctional myocardial segments in patients undergoing revascularization and consequently has akey role in guiding revascularization procedures. In addition, use of LGE in the identification of myocardial fibrosis or myocardial damage in inflammatory myocardial disease helps to differentiate the type of cardiomyopathy and to predict sudden cardiac death among patients with heart failure. The role of LGE-MRI in the field of electrophysiology through recognition of different substrate for arrythmias and guiding the ablation therapy is steadily increasing and has fundamentally changed our understanding of atrial myopathy.

Endolymphatic hydrops in the unaffected ear of patients with unilateral Ménière’s disease

PurposeCurrent studies show that frequency tuning modification is a good marker for the detection of endolymphatic hydrops (EH) employing magnetic resonance imaging (MRI) in patients with Ménière’s disease (MD). The purpose of the present study is to analyze the auditory and vestibular function with audiometric and vestibular-evoked myogenic potentials (VEMP) responses, respectively, in both the affected and unaffected ears of patients with unilateral MD using MRI as diagnostic support for the degree of EH.MethodsWe retrospectively reviewed the medical records of 76 consecutive patients with unilateral definite MD (age 55 (28–75); 39 women, 37 men). MRI was used through intravenous gadolinium administration, audiometry, and VEMPs. Functional tests were performed up to a week after the MRI. All were followed up one year after imaging utilizing clinical, auditory, and vestibular testing to rule out bilateral involvement.ResultsIn the unaffected ear, the mean pure-tone average is normal even in cases with hydrops and, for a similar severity of hydrops is significantly lower than in the affected ear. Significant differences for the amplitude of the response at 0.5 kHz, at 1 kHz between the affected and unaffected ears were found to be lower in the affected ears. The relative amplitude ratio (1 Kz–0.5 kHz) was significantly lower in the affected ear and in the case of the oVEMP response depends on the degree of EH. The response in the unaffected ear was not modified by the presence or the degree of hydrops.ConclusionIn the unaffected ear, hydrops is not associated with hearing deterioration. For a similar degree of hydrops, hearing loss is significantly greater in the affected ear. The endolymphatic hydrops in the vestibule induces a frequency bias in the VEMP response only in the affected ear and not in the unaffected ear. Because of these findings we consider that hydrops does not represent an active disorder in the unaffected ear.

Imaging Analysis of Patients With Meniere's Disease Treated With Endolymphatic Sac-Mastoid Shunt Surgery.

Objective: Endolymphatic sac surgery is effective in treating intractable Meniere's disease (MD), but the underlying mechanism is still unknown. Our study investigated the mechanism by which endolymphatic sac-mastoid shunt (EMS) surgery is effective in treating MD by means of imaging.Methods: The experiment included 19 patients with intractable MD who underwent 3D-fluid-attenuated inversion recovery (FLAIR) MRI with a 3-Tesla unit 6 h after intravenous administration of gadolinium, before EMS, and 2 years after the surgery. The enhanced perilymphatic space in the bilateral cochlea, vestibule, and canals was visualized and compared with that in the endolymphatic space by quantitatively scoring the scala vestibuli of the cochlea and by measuring the developing area of the vestibules quantitatively.Results: Gadolinium was present in the perilymph of the inner ear in the cochlea, vestibules, and canals of all patients. At the 2-year follow-up, 14 (73.68%) patients had vertigo control. Both before and 2 years after surgery, significant differences were observed in the scala vestibuli scores and the area of vestibular perilymph between the affected and healthy sides. The scala vestibuli scores and the area of vestibular perilymph, however, did not differ when comparing them before and after surgery.Conclusions: According to our results, endolymphatic hydrops was not significantly reduced by surgery. The mechanism by which EMS controls vertigo might be unrelated to the improvement in hydrops.

3D Real IR MR Findings in Acoustic Neuromas: Altered Perilymph Metabolism.

This study aimed to investigate the perilymph metabolism by analyzing the 3D real IR MR findings in acoustic neuroma (AN) after intravenous administration of gadolinium (Gd). Eleven patients (6 men and 5 women) diagnosed with AN were included, and 3D real IR MRI was performed 4hours after intravenous Gd injection. The signal intensity and details of inner ear, tumor, and internal auditory canal (IAC) by MRI were analyzed. Four patients had tumors confined to the IAC, and 5 had tumors that extended to the cerebellopontine angle cistern. The signal intensity of the cochlea, vestibule, and IAC fundus was conspicuously enhanced in 3D real IR images than the control side. One patient had a tumor in the cochlea, in which the signal intensity of the semicircular canal and vestibule was increased. One patient had an intravestibular tumor in which the signal intensity of the semicircular canal was increased and the cochlea had endolymphatic hydrops in the affected ear. The synchronously increased signal intensity in the inner ear and IAC may indicate that IAC may serve as a channel for removal of the perilymph in the inner ear; the blockage by the tumor may have changed the hydrodynamics of the perilymph to cause a longer retention of Gd in the inner ear.

Correlation Among 3-Dimensional Magnetic Resonance Cholangiography, Intraoperative Cholangiography, and Intraoperative Findings in Right Liver Donors.

A correct preoperative definition of the hepatic duct confluence anatomy of right liver living donors is pivotal in determining their candidacy for donation and planning surgery during liver transplant. Here, we evaluated the accuracy of 3-dimensional magnetic resonance cholangiography compared with intraoperative cholangiography in assessing biliary anatomy and aimed to identify imaging characteristics that may help to predict the yield of hepatic duct orifices in the right liver graft. All consecutive living hepa-tectomy donors for adult liver transplant included in this study (N = 110) were evaluated with preoperative 3-dimensional magnetic resonance cholangiography, which was performed before and after intravenous administration of gadolinium (20-40 cm³). For intraoperative cholangiography, a 4F catheter was advanced through the cystic duct, and contrast matter (5-10 mL) was injected into the biliary tree via the catheter. The number of right hepatic ducts in explanted graft was determined on the back table. Of 110 donors, 71 had type 1 (normal) biliary anatomy based on both 3-dimensional magnetic resonance and intraoperative cholangiography and 39 had abnormal biliary anatomy, with 2 having type 3 (abnormal) biliary anatomy. Normal biliary anatomy was found in back-table examination, and abnormal biliary anatomy (type 2) was found with intraoperative cholangiography. Sensitivity, specificity, and predic-tive values of 3-dimensional magnetic resonance cholangiography in revealing the biliary anatomy and anomalies were compared with intraoperative cholangiography findings. Observed final hepatic duct outcomes were also assessed. Use of 3-dimensional magnetic resonance cholangiography accurately predicted the biliary anatomy in 97 of 110 cases. Sensitivity was 80.4%, positive predictive value was 94.4%, specificity was 96.9%, and negative predictive value was 87.3%. Three-dimensional magnetic resonance cholangiography reliably represented normal biliary anatomy; the presence of anatomic variations decreased its sensitivity, making intraoperative cholangiography or duct probing necessary tools to accurately perform right hepatic duct transection.

99mTc-antitumor necrosis factor-alpha scintigraphy for the detection of inflammatory activity in rheumatoid arthritis.

Tumor necrosis factor-alpha (TNF-α) is an important inflammatory cytokine. 99mTc-anti-TNF-α antibody scintigraphy has proven to be a viable alternative to MRI in specific cases. The objective of this study was to evaluate the performance of scintigraphy with 99mTc-anti-TNF-α in the identification of inflammatory foci in individuals diagnosed with rheumatoid arthritis using MRI as the gold standard. This cross-sectional, descriptive and analytical-qualitative clinical study compared the performance of 99mTc-anti-TNF-α scintigraphy with that of MRI with intravenous administration of gadolinium (used as the gold standard) and a clinical examination (Disease Activity Score 28) in 220 joints of 20 patients with a diagnosis of rheumatoid arthritis and one healthy control. The concordance of scintigraphy with MRI in individuals with a diagnosis of rheumatoid arthritis was 79%. The accuracy, sensitivity and specificity of scintigraphy for distinguishing between inflammatory and noninflammatory sites were 92, 89, and 93%, respectively. No adverse reactions to the examinations were reported. Scintigraphy with 99mTc-anti-TNF-α was well-tolerated and had a good ability to distinguish between inflammatory and noninflammatory lesions in patients with rheumatoid arthritis.

Inner Ear Enhancement With Delayed 3D-FLAIR MRI Imaging in Vestibular Schwannoma.

To evaluate blood-labyrinth barrier permeability using delayed gadolinium enhanced three-dimensional fluid-attenuated inversion recovery (3D-FLAIR) in patients with untreated sporadic vestibular schwannoma (VS) to interrogate the etiopathogenesis of progressive sensorineural hearing loss. Prospective case series. Single institution tertiary care center. Patients with previously untreated small to medium-sized unilateral VS undergoing 3D-FLAIR imaging 10 minutes (immediate) and 5 to 8 hours (delayed) after administration of intravenous gadolinium. Comparison of cochlear and vestibular signal intensity ratios (SIRs) across immediate and delayed images and across the tumor and nontumor ear. Six of eight (75%) patients demonstrated asymmetric enhancement of inner ear structures on delayed contrast-enhanced imaging. Delayed mean cochlea and vestibule SIRs were significantly greater than immediate SIRs (cochlea: 1.91 versus 1.21 [p = 0.02]; vestibule 1.74 versus 1.15 [p = 0.02]). A higher vestibule SIR was statistically significantly associated with poorer pure-tone average and word recognition scores (p = 0.001). Ears with VS exhibited increased enhancement on delayed 3D FLAIR imaging. These findings suggest that alterations in blood-labyrinth barrier permeability may explain progressive sensorineural hearing loss in a subset of patients with untreated VS.

Endolymphatic hydrops mimicking obstructive Eustachian tube dysfunction: preliminary experience and literature review.

Aural fullness is a common symptom of middle ear diseases, most importantly Eustachian tube dysfunction (ETD). Yet, aural fullness may also be caused by inner ear disorders, such as hydropic ear diseases. Here, we report our experience with endolymphatic hydrops (EH) mimicking ETD. Furthermore, we review the literature related to (i) EH as a differential diagnosis of symptoms suggesting ETD and (ii) the pathophysiology and treatment of aural fullness due to inner ear disorders. We retrospectively included adult patients with aural fullness as chief complaint and radiographically diagnosed EH. Hearing and Eustachian tube function were assessed using audiometry, tympanometry, and tubomanometry. Primarily suspected ETD was treated by balloon dilatation of the Eustachian tube (BDET). The endolymphatic space of the inner ear was imaged using gadolinium-enhanced MRI (Gd-MRI) including a 3D-real inversion-recovery sequence after intravenous gadolinium administration. We report three affected ears of two patients (two females, age 42 and age 51) with aural fullness as chief complaint. Audiometry of main speech frequencies was normal in all affected ears. In one ear, there was a type A tympanogram and in two ears, there was a type B tympanogram. In both patients, medical treatment for ETD and BDET were unsuccessful. Gd-MRI of the inner ears revealed cochlear EH in 3/3 ears affected by aural fullness, but not in the unaffected ear. EH may underlay cases with aural fullness and could in these cases explain unsuccessful treatment for ETD. As ETD is often treated by invasive procedures, distinguishing ETD from EH as the underlying cause of aural fullness is important. Our findings raise the question whether Gd-MRI to rule out EH is indicated in patients with unexplained aural fullness, in particular after unsuccessful interventional treatment for ETD.

Relationship between video head impulse test, ocular and cervical vestibular evoked myogenic potentials, and compartmental magnetic resonance imaging classification in menière's disease.

Currently, it is possible to assess in vivo the morphology of each compartment of the endolymphatic spaces 4 hours after an intravenous administration of gadolinium on magnetic resonance imaging (MRI). The aim of this study was to assess the correlation between otolithic and ampullar functions (cervical vestibular evoked myogenic potential [cVEMP], ocular vestibular evoked myogenic potential [oVEMP], video head impulse test [VHIT]) and delayed inner ear MRI based on a compartmental, anatomically based classification that included the cochlea, the saccule, the utricle, and the ampullas. Retrospective case-control study. In this retrospective study, we performed three-dimensional fluid-attenuated inversion recovery sequences with delayed acquisition in 26 healthy subjects and 31 definite Menière's disease (MD) patients. Each subject was then graded on MRI on the basis on cochlear, saccular, utricular, and ampullar hydrops in MD patients. All patients underwent pure-tone audiometry, VHIT, cVEMP, and oVEMP testing. Cochlear, saccular, utricular, and ampullar hydrops were found on MRI in 88%, 91%, 50%, and 8.5% respectively. We found no significant correlation between the presence of saccular hydrops versus cVEMP, utricular hydrops versus oVEMP, and ampullar hydrops versus VHIT. However, the severity of endolymphatic hydrops on MRI was correlated to the degree of hearing loss. We proposed a compartmental, anatomically based classification for endolymphatic hydrops on MRI, which included the whole vestibular compartment. Using this classification, we observed increasing morphological changes as the disease evolved, affecting first the saccule, then the utricle, and finally the ampullas. The severity of vestibular endolymphatic hydrops is only correlated to hearing loss severity. 3 Laryngoscope, 130:E444-E452, 2020.

PO 18120 - Eccrine poroma associated with a poroid hidradenoma in a large single lesion over the foot

Introduction: Eccrine poroma (EP) and poroid hidradenoma (PH) are rare benign neoplasms derived from eccrine sweat glands of the epithelium. Both are variants of poroid neoplasms and rarely become malignant. This report describes the clinical presentation, radiographic and pathological features as well as the treatment of a rare association of EP and PH in a large single lesion over the foot. Case Report: We present a 55-year-old male patient with a large soft tissue mass over the midfoot (approximately 7 cm in length and 4 cm width). It started as a hyperchromic black spot on the skin and has slowly grown over the last eight years. One year prior, pain increased significantly. There was no history of trauma, infection or other tumor in this part of the foot. In the physical exam, the tumor had well-defined edges, fibroelastic consistency and was not adherent to the surrounding soft tissue. Preoperative planning included radiographic exams: X-ray and magnetic resonance imaging (MRI). On the MRI, the tumor showed a low signal intensity on T1-weighted images, with heterogeneous high and low signal intensities on T2-weighted images. Strong contrast enhancement was observed after intravenous gadolinium administration in the base portion. The peripheral portion showed a low signal intensity without enhancement. We decided on total resection, and the procedure was performed in January of 2017. The surgical approach was a longitudinal dorsomedial incision over the first ray starting from the ankle joint to the distal third of the first metatarsal. The entire tumor was excised with clean margins and sent for anatomopathological analysis and histopathological examination. Histopathologic examination showed that the tumor was a poroid neoplasm consisting of both dermis (poroid hidradenoma) and epidermis (eccrine poroma) components. There were no features of malignancy. After 20 months of surgery, patient remains asymptomatic with no signs of recurrence of the tumor. Conclusion: Skin tumors must be born in mind in the differential diagnosis of a chronic mass in the foot. Surgical treatment for this type of tumor is curative and prevents recurrence and malignant change.

Endolymphatic Hydrops, Evaluated Using 3T MRI in Patients with Clinically Confirmed Meniere Disease

Ménière’s disease (MD) is characterized by intermittent episodes of vertigo with fluctuating sensorineural hearing loss, tinnitus, and aural fullness. Despite numerous studies, the etiology of this disorder remains poorly understood and thus diagnostic criteria are mainly clinical. Development and progress in magnetic resonance imaging (MRI) techniques, in 2007, has enabled visualization of endolymphatic hydrops, which was the milestone achievement. We present two cases of patients with clinically confirmed MD with a set of audiological, otoneurological examinations and MRI performed. Structures of the inner ear were visualized using contrast-enhanced MR imaging after a 4-hour delayed intravenous gadolinium administration. The cochlea and vestibule were evaluated separately and classified using Barath grading scale. Endolymphatic hydrops in the clinically affected ears was confirmed using MRI. Due to disabling and intractable MD, a decision about vestibular neurectomy was made.

Usefulness of dynamic contrast-enhanced magnetic resonance images for distinguishing between pyogenic spondylitis and tuberculous spondylitis.

Dynamic contrast-enhanced (DCE)-MRI is used for examining the features of malignant tumours in radiology, and we can obtain more information in terms of the diffusion of the media over the course of time. The purpose of this study was to clarify the usefulness of DCE-MRI for distinguishing pyogenic spondylitis (PS) and tuberculous spondylitis (TB). Forty-five consecutive patients diagnosed with PS (68.6 ± 11.1years old, males 30 and females 15) and 14 with TB (73.9 ± 9.1years old, males 6 and females 8) were involved. DCE-MRI consisted of serial six sagittal images which were taken every 20s after intravenous gadolinium administration. Degree of enhancement, presence of epidural abscess, presence of necrosis in vertebra, presence of enhancement in disc lesion, pattern of diffusion, and maximum contrast index were examined and compared between PS and TB. Degree of enhancement, percentage of epidural abscess, and percentage of necrosis in vertebra were 2.1 ± 0.5 and 1.8 ± 0.8, 60.7% and 100%, 50.0% and 66.7% for PS and TB, respectively, without statistical difference. Maximum contrast index, percentage of the diffusion pattern from the disc, and percentage of enhanced disc were 108.1 ± 22.3 and 78.2 ± 35.6s, 89.3% and 0%, and 53.6% and 0% for PS and TB, respectively, with statistical significance. This study indicated that longer maximum contrast index, higher likelihood of diffusion pattern from the disc, and higher likelihood of enhanced disc are more specific to PS than TB. This less invasive imaging technique is useful for more accurate diagnosis of PS and TB. These slides can be retrieved under Electronic Supplementary Material.

Comprehensive comparison of MR image quality between intratympanic and intravenous gadolinium injection using 3D real IR sequences

Background: Intratympanic and intravenous gadolinium administration is used to visualise endolymphatic hydrops.Aims/objectives: The goal of this study was to compare the image quality between intratympanic (IT-method) and intravenous (IV-method) gadolinium administration using three-dimensional inversion recovery with real reconstruction (3D real IR) sequences.Materials and methods: A number of 152 patients with Meniere’s disease were included. The 3D real IR sequence was performed 24 h after IT administration or 4 h after IV administration. The detection rate of endolymphatic hydrops, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) of the two methods were compared. Specifically, the average image scores of the two methods were evaluated by two radiologists.Results: The SNRROI and CNRs of the IT-method were higher than those of the IV-method, whereas no significant difference between the IT-method and IV-method with regard to the SNRB was found. The average image scores were 3.49 ± 0.12 and 3.30 ± 0.12 for the IT-method and IV-method, respectively (p = .229). No statistically significant difference was found between two methods in terms of the detection rate of endolymphatic hydrops.Conclusions and significance: IT-method images can display endolymphatic hydrops more precisely than IV-method images. The IV-method can be used as an alternative to the IT-method in clinical applications to some extent.

Imaging of Ménière Disease.

Visualization of the morphologic substrate of Ménière disease, the endolymphatic hydrops, can be performed using noncontrast or contrast-enhanced MR imaging techniques. Noncontrast MR imaging uses a heavily T2-weighted sequence; however, its reproducibility remains to be confirmed. Contrast-enhanced MR imaging techniques mainly use a 3-dimensional fluid-attenuated inversion recovery sequence after intratympanic gadolinium administration or after a 4-hour delayed intravenous gadolinium administration. The latter technique is most frequently used and is able to detect and grade Ménière disease. It is a reliable technique with a high diagnostic accuracy, enabling visualization of endolymphatic hydrops.

Quantitative evaluation of endolymphatic hydrops with MRI through intravenous gadolinium administration and VEMP in unilateral definite Meniere's disease.

To help clinicians to further understand the significance of vestibular-evoked myogenic potential (VEMP) examinations to diagnose MD and the quantitative relationship between VEMP and MRI in assessing the location and degree of endolymphatic hydrops (EH) in definite Meniere's disease (MD) patients. Fifty-six patients with unilateral definite MD participated in this study, which used MRIs through intravenous gadolinium administration (IV-Gd), audiometry, caloric tests and VEMP tests. The VEMP results of 26 healthy volunteers were used as a normal reference value. The participants were found through MRI to have differing degrees of vestibular and cochlear EH. Quantitative comparison of MRI and VEMP results found that the response rates of oVEMP decreased with cochlear EH increasing; the asymmetry ratio (AR) of oVEMP can be used to find whether cochlear EH or not, and the P1-N1 amplitude was lower in the extreme cochlear EH group (P < 0.01). The AR of cVEMP was larger in severe vestibular EH group than that of the mild or no vestibular EH group (P < 0.01). The correlation between the degree of cochlear EH and the mean PTA threshold was statistically significant (P < 0.05). The duration of MD correlated positively with vestibular EH (P < 0.05). The abnormal rate of caloric tests was higher in severe vestibular EH group than that of the mild or no vestibular EH group (P < 0.05). The advantages of MRIs by IV-Gd administration were obvious in assessing the location and degree of EH. oVEMP and PTA can be indirectly used to evaluate the extent of cochlear EH, cVEMP and caloric tests can be used to assess the extent of vestibular EH on the condition of absent MRIs.