STUDY DESIGN: Case report OBJECTIVES: We report a case of surgically proven tophaceous gout of the lumbar spine at the L5-S1 level in a 43-year-old man that mimicked infectious spondylodiscitis and epidural abscess on magnetic resonance (MR) images. SUMMARY OF LITERATURE REVIEW: Some patients have chronic back pain with an epidural mass. Among the many causes of epidural masses, tophaceous gout of the lumbar spine is very rare. MATERIALS AND METHODS: A 43-year-old man presented with fever and chronic back pain with radiating pain. In an MR image of L4-5, an abnormal subcutaneous mass was found in the posterior epidural space. The subcutaneous mass was isointense on T1-weighted images compared with the intervertebral disc, and focally and strongly hyperintense and heterogeneous on T2-weighted images. After the intravenous administration of gadolinium contrast, the mass was fairly homogenous, with a low signal intensity and without enhancement. With the diagnosis of infective spondylitis with epidural abscess, we performed a decompressive mass resection. RESULTS: The pathologic examination revealed multinuclear giant cells and amorphous crystalline fibrous tissue. The lesion was diagnosed as tophaceous gout. CONCLUSIONS: This case underscores the importance of considering tophaceous gout in the differential diagnosis of an epidural mass in a patient with chronic back pain.
Administration, Intravenous ; Adult ; Back Pain ; Crystallins ; Diagnosis ; Diagnosis, Differential ; Discitis ; Epidural Abscess ; Epidural Space ; Fever ; Gadolinium ; Giant Cells ; Gout ; Humans ; Intervertebral Disc ; Magnetic Resonance Imaging ; Spine ; Spondylitis

The purpose of the study was to observe changes in endolymphatic hydrops by using intratympanic injection of gadolinium and magnetic resonance imaging (MRI) before and after endolymphatic sac surgery in patients with unilateral Meniere's disease. Thirteen patients with unilateral Meniere's disease undergoing endolymphatic sac surgery were retrospectively and prospectively analyzed. Three-dimensional fluid-attenuated inversion recovery or three-dimensional real inversion recovery MRI was performed 24 h after an intratympanic injection of gadolinium to grade the presence of endolymphatic hydrops. Among the 13 patients with hydrops confirmed by preoperative MRI, vestibular hydrops had no significant change in all patients; cochlear hydrops became negative in 2 patients, and remained unchanged in the other 11 patients after surgery. Definite vertigo attacks were substantially controlled in one patient and completely controlled in 12 patients during a follow-up period of 8-34 months after surgery. The hearing levels were improved in 3 patients, remained unchanged in 7 patients, and decreased in 3 patients. In conclusion, endolymphatic sac surgery does not always alleviate endolymphatic hydrops in patients with Meniere's disease. Relief from vertigo cannot always be attributed to the remission of hydrops. A change in hearing levels cannot be explained by hydrops status alone.
Adult ; Aged ; Contrast Media ; administration & dosage ; Endolymphatic Hydrops ; diagnostic imaging ; pathology ; surgery ; Endolymphatic Sac ; diagnostic imaging ; pathology ; surgery ; Female ; Gadolinium ; administration & dosage ; Humans ; Imaging, Three-Dimensional ; Magnetic Resonance Imaging ; Male ; Meniere Disease ; diagnostic imaging ; pathology ; surgery ; Middle Aged

Acute respiratory distress syndrome (ARDS) is a medical emergency that threatens life. To this day, ARDS is very rarely reported by iodine contrast media, and there is no reported case of ARDS induced by gadolinium contrast media. Here, we present a case with ARDS after the use of gadobutrol (Gadovist) as a magnetic resonance imaging (MRI) contrast medium. A 26 years old female without any medical history, including allergic diseases and without current use of drugs, visited the emergency room for abdominal pain. Her abdominopelvic computed tomography with iodine contrast media showed a right ovarian cyst and possible infective colitis. Eighty-three hours later, she underwent pelvis MRI after injection of 7.5 mL (0.1 mL/kg body weight) of gadobutrol (Gadovist) to evaluate the ovarian cyst. She soon presented respiratory difficulty, edema of the lips, nausea, and vomiting, and we could hear wheezing upon auscultation. She was treated with dexamethasone, epinephrine, and norepinephrine. Her chest X-ray showed bilateral central bat-wing consolidative appearance. Managed with mechanical ventilation, she was extubated 3 days later and discharged without complications.
Adult ; Animals ; Contrast Media/administration & dosage/*adverse effects ; Female ; Gadolinium ; Humans ; Magnetic Resonance Imaging/*methods ; *Organometallic Compounds/adverse effects ; Respiratory Distress Syndrome, Adult/*chemically induced ; Tomography, X-Ray Computed

OBJECTIVETo discuss the necessity of MRI as a routine examination for diagnosis of glomus tumor.

METHODSFrom Nov. 2013 to July 2014, 7 cases of glomus tumor were treated in our department. All patients had typical clinical symptoms of glomus tumor and received preoperative X-ray and/or MRI examination. The diagnosis was confirmed by postoperative histopathologic examination. All the patients were retrospectively analyzed by reviewing the preoperative examination results and PubMed search results.

RESULTS2 cases underwent only X-ray examination before operation with no positive results. 3 cases underwent both X-ray and MRI. No positive finding happened in X-ray, while MRI showed glomus tumor characteristic on T1- and T2-weighted images which demonstreated a more intense signal after injection of gadolinium. The last 2 cases underwent only MRI examination, which revealed positive images of glomus tumor.

CONCLUSIONSMRI plays an important role in diagnosis of glomus tumor and should be adopted as a routine examination.

BACKGROUND/AIMS: The therapeutic effect of transarterial chemoembolization (TACE) against hepatocellular carcinoma (HCC) is usually assessed using multidetector computed tomography (MDCT). However, dense lipiodol depositions can mask the enhancement of viable HCC tissue in MDCT. Contrast-enhanced ultrasonography (CEUS) could be effective in detecting small areas of viability and patency in vessels. We investigated whether arterial enhancement in CEUS after treatment with TACE can be used to detect HCC viability earlier than when using MDCT. METHODS: Twelve patients received CEUS, MDCT, and gadoxetic-acid-enhanced dynamic magnetic resonance imaging (MRI) at baseline and 4 and 12 weeks after TACE. The definition of viable HCC was defined as MRI positivity after 4 or 12 weeks. RESULTS: Eight of the 12 patients showed MRI positivity at 4 or 12 weeks. All patients with positive CEUS findings at 4 weeks (n=8) showed MRI positivity and residual viable HCC at 4 or 12 weeks. Five of the eight patients with positive CEUS findings at 4 weeks had negative results on the 4-week MDCT scan. Four (50%) of these eight patients did not have MRI positivity at 4 weeks and were ultimately confirmed as having residual HCC tissue at the 12-week MRI. Kappa statistics revealed near-perfect agreement between CEUS and MRI (kappa=1.00) and substantial agreement between MDCT and MRI (kappa=0.67). CONCLUSIONS: In the assessment of the response to TACE, CEUS at 4 weeks showed excellent results for detecting residual viable HCC, which suggests that CEUS can be used as an early additive diagnosis tool when deciding early additional treatment with TACE.
Aged ; Aged, 80 and over ; Antineoplastic Agents/administration & dosage ; Carcinoma, Hepatocellular/pathology/therapy/*ultrasonography ; Chemoembolization, Therapeutic ; Contrast Media/*chemistry ; Female ; Gadolinium DTPA/chemistry ; Humans ; Liver Neoplasms/pathology/therapy/*ultrasonography ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Pilot Projects ; Tomography, X-Ray Computed ; Treatment Outcome

OBJECTIVE: To compare gadoxetic acid injection rates of 0.5 mL/s and 1 mL/s for hepatic arterial-phase magnetic resonance (MR) imaging. MATERIALS AND METHODS: In this prospective study, 101 consecutive patients with suspected focal liver lesions were included and randomly divided into two groups. Each group underwent dynamic liver MR imaging using a 3.0-T scanner after an intravenous injection of gadoxetic acid at rates of either 0.5 mL/s (n = 50) or 1 mL/s (n = 51). Arterial phase images were analyzed after blinding the injection rates. The signal-to-noise ratios (SNRs) of the liver, aorta, portal vein, hepatic vein, spleen, and pancreas were measured. The contrast-to-noise ratios (CNRs) of the hepatocellular carcinomas (HCC) were calculated. Finally, two experienced radiologists were independently asked to identify, if any, HCCs in the liver on the images and score the image quality in terms of the presence of artifacts and the proper enhancement of the liver, aorta, portal vein, hepatic vein, hepatic artery, spleen, pancreas, and kidney. RESULTS: The SNRs were not significantly different between the groups (p = 0.233-0.965). The CNRs of the HCCs were not significantly different (p = 0.597). The sensitivity for HCC detection and the image quality scores were not significantly different between the two injection rates (p = 0.082-1.000). CONCLUSION: Image quality and sensitivity for hepatic HCCs of arterial-phase gadoxetic acid-enhanced MR were not significantly improved by reducing the contrast injection rate to 0.5 mL/s compared with 1 mL/s.
Adult ; Aged ; Aged, 80 and over ; Artifacts ; Carcinoma, Hepatocellular/*radiography ; Contrast Media/*administration & dosage/*diagnostic use ; Dose-Response Relationship, Drug ; Female ; Gadolinium DTPA/*administration & dosage/*diagnostic use ; Hepatic Artery ; Humans ; Liver Neoplasms/*radiography ; *Magnetic Resonance Imaging ; Male ; Middle Aged ; Prospective Studies ; Sensitivity and Specificity ; Signal-To-Noise Ratio

PURPOSE: Single dose gadolinium (Gd) enhanced fluid-attenuated inversion recovery (FLAIR) is helpful for visualizing superficial parenchymal metastases. However, the usefulness of FLAIR with a higher dose of Gd is uncertain. The aim of our study was two-folds: first, to prove that the signal to noise ratio (SNR) of small brain metastases is higher than large brain metastases on double-dose (DD) enhanced FLAIR and, second, to explore the added value of DD Gd enhanced FLAIR in relation to T1 GRE for evaluating small brain metastases. MATERIALS AND METHODS: For the first purpose, 50 pairs of small (2 mm5 mm) were included. The difference in the SNR and contrast ratio (CR) between small and large metastases on DD Gd-enhanced 3D T2 FLAIR was compared by Wilcoxon signed-rank tests. For the second purpose, a total of 404 small metastases were included. The diagnostic sensitivities between 3D T1 gradient echo (GRE) alone and combined results of 3D T1 GRE and 3D T2 FLAIR were compared with McNemar test. RESULTS: The SNR and CR of small brain metastases were significantly higher than those of large brain metastases (p<0.001). In qualitative analysis, the diagnostic sensitivities for small brain metastases were significantly higher for 3D T1 GRE plus 3D T2 FLAIR than 3D T1 GRE alone regardless of scan time (p<0.001). CONCLUSION: Small brain metastases showed higher signal intensity than large brain metastases on the DD Gd enhanced 3D T2 FLAIR images. DD Gd enhanced 3D T2 FLAIR imaging may have a complementary role to 3D T1 GRE for evaluating small brain metastases.
Adult ; Aged ; Brain Neoplasms/*pathology ; Contrast Media/administration & dosage/*diagnostic use ; Female ; Gadolinium/administration & dosage/*diagnostic use ; Humans ; Imaging, Three-Dimensional ; Magnetic Resonance Imaging/*methods ; Male ; Middle Aged ; Retrospective Studies ; Signal-To-Noise Ratio

PURPOSE: To investigate the blood pharmacokinetics and bio-distribution of DTPA-bis-amide (L3) Gd(III) complexes. MATERIALS AND METHODS: The pharmacokinetics and bio-distribution of Gd (L3)(H2O).nH2O were investigated in Sprague-Dawley rats after intravenous administration at a dose of 0.1 mmol Gd/kg. The Gd content in the blood, various tissues, and organs was determined by ICP-AES. Blood pharmacokinetic parameters were calculated using a two-compartment model. RESULTS: The half-lives of alphaphase and betaphase Gd (L3)(H2O).nH2O were 2.286+/-0.11 min and 146.1+/-7.5 min, respectively. The bio-distribution properties reveal that the complex is mainly excreted by the renal pathway, and possibly excreted by the hepatobiliary route. The concentration ratio of Gd (III) was significantly higher in the liver and spleen than in other organs, and small amounts of Gd (III) ion were detected in the blood or other tissues of rats only after 7 days of intravenous administration. CONCLUSION: The MRI contrast agent Gd (L3)(H2O).nH2O provides prolonged blood pool retention in the circulation and then clears rapidly with minimal accumulation of Gd(III) ions. The synthesis of gadolinium complexes with well-balanced lipophilicity and hydrophilicity shows promise for their further development as blood pool MRI contrast agents.
Administration, Intravenous ; Animals ; Contrast Media ; Gadolinium ; Hydrophobic and Hydrophilic Interactions ; Ions ; Liver ; Magnetic Resonance Imaging ; Models, Animal* ; Pharmacokinetics* ; Rats* ; Rats, Sprague-Dawley ; Spleen

A 10-year-old female patient presented with a rapidly growing nodular mass lesion on her right frontal area. On skull radiography and computed tomography (CT) imaging, this mass had a well-demarcated punch-out lesion with a transdiploic, exophytic soft tissue mass nodule on the frontal scalp. Magnetic resonance (MR) imaging revealed the presence of a 1.5x1.2x1 cm sized calvarial lesion. This lesion was hypointense on T1 and heterogenous hyperintense on T2 weighted MR images, and exhibited heterogeneous enhancement of the soft tissue filling the punch-out lesion after intravenous administration of gadolinium. En block removal of the tumor with resection of the rim of the normal bone was performed. The pathological diagnosis was intravascular papillary endothelial hyperplasia (IPEH). After surgery, no recurrence was found for 8 months. IPEH is a rare and benign reactive lesion usually found in thrombosed subcutaneous blood vessels. Involvement of skull bone is rare. In this article, we present a case of IPEH involving the calvarium, in a 10-year-old woman.
Administration, Intravenous ; Blood Vessels ; Child ; Female ; Gadolinium ; Humans ; Hyperplasia ; Magnetic Resonance Spectroscopy ; Recurrence ; Scalp ; Skull

BACKGROUND: Dexmedetomidine is a highly selective alpha2-adrenoceptor agonist that is widely used for sedation and analgesia during the perioperative period. Intravenous administration of dexmedetomidine induces transient hypertension due to vasoconstriction via the activation of the alpha2-adrenoceptor on vascular smooth muscle. The goal of this in vitro study is to investigate the calcium-dependent mechanism underlying dexmedetomidine-induced contraction of isolated endothelium-denuded rat aorta. METHODS: Isolated endothelium-denuded rat thoracic aortic rings were suspended for isometric tension recording. Cumulative dexmedetomidine concentration-response curves were generated in the presence or absence of the following inhibitors: alpha2-adrenoceptor inhibitor rauwolscine; voltage-operated calcium channel blocker verapamil (5 x 10(-7), 10(-6) and 5 x 10(-5) M); purported inositol 1,4,5-trisphosphate receptor blocker 2-aminoethoxydiphenylborate (5 x 10(-6), 10(-5) and 5 x 10(-5) M); phospholipase C inhibitor U-73122 (10(-6) and 3 x 10(-6) M); and store-operated calcium channel inhibitor gadolinium chloride hexahydrate (Gd3+; 5 x 10(-6) M). Dexmedetomidine concentration-response curves were also generated in low calcium concentrations (1 mM) and calcium-free Krebs solution. RESULTS: Rauwolscine, verapamil, and 2-aminoethoxydiphenylborate attenuated dexmedetomidine-induced contraction in a concentration-dependent manner. Low calcium concentrations attenuated dexmedetomidine-induced contraction, and calcium-free Krebs solution nearly abolished dexmedetomidine-induced contraction. However, U-73122 and Gd3+ had no effect on dexmedetomidine-induced contraction. CONCLUSIONS: Taken together, these results suggest that dexmedetomidine-induced contraction is primarily dependent on extracellular calcium concentrations that contribute to calcium influx via voltage-operated calcium channels of isolated rat aortic smooth muscle. Dexmedetomidine-induced contraction is mediated by alpha2-adrenoceptor stimulation. Dexmedetomidine-induced contraction appears to be partially mediated by calcium release from the sarcoplasmic reticulum.
Administration, Intravenous ; Analgesia ; Animals ; Aorta ; Calcium ; Calcium Channels ; Contracts ; Dexmedetomidine ; Estrenes ; Gadolinium ; Hypertension ; Inositol 1,4,5-Trisphosphate ; Isotonic Solutions ; Muscle, Smooth ; Muscle, Smooth, Vascular ; Perioperative Period ; Pyrrolidinones ; Rats ; Sarcoplasmic Reticulum ; Type C Phospholipases ; Vasoconstriction ; Verapamil ; Yohimbine