Introduction of Meglumine Diatrizoate into the Middle Cranial Fossa: A Rare Fatal Complication of Temporomandibular Joint Arthrography.

The authors here report a rare fatal complication of temporomandibular joint (TMJ) arthrography. A 57-year-old woman suddenly exhibited spasm and dizziness during TMJ arthrography. A multislice CT scanning of head demonstrated a defect in the roof of the glenoid fossa and unanticipated introduction of meglumine diatrizoate into the middle cranial fossa, which should account for neurotoxic symptoms of the patient and could be fatal if not appropriately treated in time. As TMJ puncture is widely performed in clinical practice and generally considered a safe technique, this case might serve as a reminder of the potential risk of the anatomical variation-a defect in the roof of the glenoid fossa-to TMJ clinical practitioners.

Oral water soluble contrast for malignant bowel obstruction.

BACKGROUND: Malignant bowel obstruction (MBO) is a common problem in patients with intra-abdominal cancer. Oral water soluble contrast (OWSC) has been shown to be useful in the management of adhesive small bowel obstruction in identifying patients who will recover with conservative management alone and also in reducing the length of hospital stay. It is not clear whether the benefits of OWSC in adhesive small bowel obstruction are also seen in patients with MBO. OBJECTIVES: To determine the reliability of OWSC media and follow-up abdominal radiographs in predicting the success of conservative treatment in resolving inoperable MBO with conservative management.To determine the efficacy and safety of OWSC media in reducing the duration of obstruction and reducing hospital stay in people with MBO. SEARCH METHODS: We identified studies from searching Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and MEDLINE in Process, Embase, CINAHL, Science Citation Index (Web of Science) and Conference Proceedings Citation Index - Science (Web of Science). We also searched registries of clinical trials and the CareSearch Grey Literature database. The date of the search was the 6 June 2017. SELECTION CRITERIA: Randomised controlled trials (RCTs), or prospective controlled studies, that evaluated the diagnostic potential of OWSC in predicting which malignant bowel obstructions will resolve with conservative treatment.RCTs, or prospective controlled studies, that assessed the therapeutic potential of OWSC in managing MBO at any level compared with placebo, no intervention or usual treatment or supportive care. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. We assessed risk of bias and assessed the evidence using GRADE and created a 'Summary of findings' table. MAIN RESULTS: We found only one RCT meeting the selection criteria for the second objective (therapeutic potential) of this review. This study recruited nine participants. It compared the use of gastrografin versus placebo in adult patients with MBO with no indication for further intervention (surgery, endoscopy) apart from standardised conservative management.The overall risk of bias for the study was high due to issues with low numbers of participants, selective reporting of outcomes and a high attrition rate for the intervention arm.Primary outcomesThe included trial was a pilot study whose primary outcome was to test the feasibility for a large study. The authors reported specifically on the number of patients screened, the number recruited and reasons for exclusion; this was not the focus of our review.Due to the low number of participants, the authors of the study decided not to report on our primary outcome of assessing the ability of OWSC to predict the likelihood of malignant small bowel obstruction resolving with conservative treatment alone (diagnostic effect). It also did not report on our primary outcome of rate of resolution of MBO in patients receiving OWSC compared with those not receiving it (therapeutic effect).The study reported that no issues regarding safety or tolerability of either gastrografin or placebo were identified. The overall quality of the evidence for the incidence of adverse events with OWSC was very low, downgraded twice for serious limitations to study quality (high risk of selective reporting and attrition bias) and downgraded once for imprecision (sparse data).Secondary outcomesThe study planned to report on this review's secondary outcome measures of length of hospital stay and time from administration of OWSC to resolution of MBO. However the authors of the study decided not to do so due to the low numbers of patients recruited. The study did not report on our secondary outcome measure of survival times from onset of inoperable MBO until death. AUTHORS' CONCLUSIONS: There is insufficient evidence from RCTs to determine the place of OWSC in predicting which patients with inoperable MBO will respond with conservative treatment alone. There is also insufficient evidence from RCTs to determine the therapeutic effects and safety of OWSC in patients with malignant small bowel obstruction.

Laxative-free CT colonography.

OBJECTIVES: The aim of this study was to determine if the introduction of faecal tagging to CT colonography (CTC) made the examination easier to tolerate or reduced the number of false-positives. METHODS: Our department changed bowel preparation for CT colonography from Picolax (Ferring Pharmaceuticals Ltd, London, UK) to Gastrografin (Bracco Diagnostics Inc, Princeton, NJ) only with a modified diet. Questionnaires were given to a subgroup of patients within these cohorts. The numbers of false-positives were compared between two cohorts before and after this change. false-positives were defined as lesions reported on CT that were not confirmed by subsequent endoscopic examination. Polyps were matched if they were in the same or adjacent segments, and were within 5 mm of the reported size. RESULTS: 412 patients were identified from the Picolax cohort, and 116 from the Gastrografin cohort. 62 patients in each group completed questionnaires. Gastrografin produced less diarrhoea; 34% had five or more bowel motions in the previous day and night, compared with 77% for Picolax (p<0.001), although more patients found drinking it unpleasant compared with Picolax (85% reported drinking Picolax as "easy" vs 61% for Gastrografin; p=0.002). Picolax produced more non-diagnostic examinations, although this difference was not statistically significant. There was not a significant reduction in the numbers of false-positives (2 out of 112 for Gastrografin group, 14 out of 389 for the Picolax group; p=0.54). CONCLUSION: Switching from Picolax to Gastrografin as a CTC preparation technique produced less diarrhoea, but did not reduce the number of false-positives.

Iodixanol versus low-osmolar contrast media for prevention of contrast induced nephropathy: meta-analysis of randomized, controlled trials.

BACKGROUND: Contrast-induced nephropathy (CIN) is associated with significant morbidity and mortality. The objective of our meta-analysis was to assess the efficacy of iodixanol compared with low-osmolar contrast media (LOCM) for prevention of CIN. METHODS AND RESULTS: We searched MEDLINE, the Cochrane Central Register of Controlled Trials, and internet sources of cardiology trial results for individual and relevant reviews of randomized, controlled trials, for the terms contrast media, contrast nephropathy, renal failure, iodixanol, Visipaque, and low-osmolar contrast media. All studies reported an incidence rate of CIN for each study group; there was no restriction on the definition of CIN. There were no restrictions on journal type or patient population. Overall, 36 trials were identified for analysis of aggregated summary data on 7166 patients; 3672 patients received iodixanol and 3494 patients received LOCM. Overall, iodixanol showed no statistically significant reduction in CIN incidence below that observed with heterogeneous comparator agents (P=0.11). Analysis of patient subgroups revealed that there was a significant benefit of iodixanol when compared with iohexol alone (odds ratio, 0.25; 95% confidence interval, 0.11 to 0.55; P<0.001) but not when compared with LOCM other than iohexol or with other ionic dimers or among patients receiving intra-arterial contrast injections or among patients undergoing coronary angiography with or without percutaneous intervention. CONCLUSIONS: Analysis of aggregated summary data from multiple randomized, controlled trials of iodixanol against diverse LOCMs for heterogeneous procedures and definitions of CIN show an iodixanol-associated reduction that is suggestive but statistically nonsignificant.

Effects of acetylcysteine and probucol on contrast medium-induced depression of intrinsic renal glutathione peroxidase activity in diabetic rats.

BACKGROUND: Antioxidants such as N-acetylcysteine and probucol have been used to protect patients from contrast media-induced nephrotoxicity. The mechanisms underlying these protective effects are not well understood. We hypothesized that acetylcysteine and probucol alter the activity of endogenous antioxidant enzyme activity. METHODS: Four weeks after induction of diabetes with streptozotocin, diabetic and nondiabetic rats were divided into three groups. Group 1 rats did not receive any antioxidant agents. Group 2 rats were treated with acetylcysteine and group 3 rats with probucol for 1 week before injection of the contrast medium diatrizoate (DTZ). RESULTS: We found that diabetic rats had higher renal glutathione peroxidase (GPx) activity than normal rats. DTZ suppressed renal GPx activity significantly in both group 1 diabetic and normal rats. Interestingly, renal GPx activity in both diabetic and normal rats pretreated with acetylcysteine or probucol was not inhibited by DTZ. Renal superoxide dismutase (SOD) increased significantly in normal rats after DTZ injection, but not in diabetic rats. Finally, acetylcysteine or probucol did not significantly influence renal SOD. CONCLUSIONS: These findings suggest that the renal protective effects of acetylcysteine and probucol against contrast-induced oxidative stress and nephrotoxicity may be mediated by altering endogenous GPx activity.

The role of theophylline in contrast-induced nephropathy: a case-control study.

BACKGROUND: Various strategies for the prevention of contrast-induced nephropathy (CN) have been studied, with conflicting results. Adenosine may play an important role in the pathogenesis of CN. This study prospectively assessed the role of oral theophylline in the prevention of CN. METHODS: We randomized into two groups 70 patients with diabetes mellitus who were undergoing coronary angiography (CAG) with high-osmolar contrast media. Group I (n=35) underwent routine CAG, and group II (n=35) received oral theophylline 200 mg b.d. 24 h before and for 48 h after CAG. Serum Na(+), K(+), blood urea nitrogen (BUN), creatinine, osmolality, glomerular filtration rate (GFR) and urinalysis were performed before and after CAG. The (99m)Tc-DTPA-clearance method was used to assess GFR. RESULTS: Following angiography, patients in the control group showed a significant rise in serum creatinine (1.19+/-0.23 vs 1.44+/-0.32 mg/dl, P=0.003) and BUN (13.95+/-2.61 vs 17.55+/-3.9 mg/dl, P=0.01) along with a fall in GFR (85.4+/-14.7 vs 66.85+/-14.8 ml/min, P=0.008). The mean percentage fall in GFR was 35.8%. There was no significant change in serum creatinine (1.16+/-0.18 vs 1.24+/-0.21 mg/dl), BUN (12.8+/-3.36 vs 14.8+/-2.5 mg/dl) and GFR (86.8+/-15.8 vs 80.3+/-16.0 ml/min) in those receiving theophylline. No patient in the theophylline group had a >25% rise in serum creatinine, compared with 7/35 in the control group (P=0.017). In the control group, 11/35 (31%) developed CN, as demonstrated by a >/=25% fall in GFR, while only one patient in the theophylline group had a fall in GFR (P=0.004). None of the pre-angiographic variables could predict the development of CN. CONCLUSIONS: Following the use of high-osmolar contrast media for routine CAG, CN may develop in 31% of diabetic patients. Patients who received prophylactic oral theophylline had a significantly lower risk of CN than those who did not.

Prevention of contrast medium-induced renal vasospasm by phosphodiesterase inhibition.

RATIONALE AND OBJECTIVES: This study investigated the involvement of cyclic adenosine monophosphate (cAMP) in contrast medium-induced renal vasomotor effects and the efficacy of selective phosphodiesterase (PDE) inhibitors influencing cAMP in preventing contrast medium-induced renal vasospasm. METHODS: Isometric contractions of rabbit renal artery rings were subjected to increasing concentrations of the ionic contrast medium sodium/meglumine diatrizoate (DIA) and the nonionic contrast media iopamidol (IOP) and iodixanol (IOD) and compared with a potassium chloride control. Subsequently increasing concentrations of the nonselective phosphodiesterase inhibitors theophylline and papaverine and the following selective phosphodiesterase inhibitors were applied: vinpocetine, trequinsin, zardaverine, rolipram, and dipyridamole (subtypes I-V) before restimulation of the arterial tissue with contrast medium. RESULTS: Diatrizoate, iopamidol, and iodixanol induced contractions up to 30%, 15%, and 3.5% of the potassium chloride control, respectively. All phosphodiesterase inhibitors markedly inhibited the contrast medium-induced contractions in a dose-dependent manner. The selective phosphodiesterase inhibitors rolipram and trequinsin attenuated these contractions significantly more (92% and 94%) than did zardaverine, dipyridamole, and vinpocetine, with an inhibitory potency of 37%, 41%, and 62%, respectively. CONCLUSIONS: Nonionic contrast media induced renal vasoconstriction less potently than ionic contrast media. Significant differences in the ability to prevent contrast medium-induced vasoconstriction were observed among the various phosphodiesterase subtypes studied. selective phosphodiesterase inhibition with inhibitor subtypes II and IV showed the most promising results in specifically preventing contrast medium-induced renal vasospasm.

Reacciones adversas por uso intravenoso de medios de contraste iónicos monómeros en tomografía computada / Adverse reactions by intravenous ion monomerics contrast media use in computarized tomography

Los medios de contraste iónicos monómeros son los de uso más frecuente en estudios contrastados intravenosos en tomografía computada. Se describen las reacciones adversas de dos productos comerciales en los cuales el átomo de hidrógeno se reemplazó exclusivamente por meglumina (sin sodio) y que se diferencian sólo en la molécula R3 (diatrizoato en uno y ioxitalamato en el otro). Del registro y análisis de dos series, de más de 600 pacientes cada una, se concluye que ambos productos son igualmente seguros (reacciones graves y medianas) pero estadísticamente diferentes (p<0.05) en la frecuencia de reacciones leves

Local reactions after injection of iodinated contrast material: detection, management, and outcome.

RATIONALE AND OBJECTIVES: The authors assessed the frequency, sequelae, and risk factors of extravasation of intravenously administered iodinated contrast media. MATERIALS AND METHODS: All patients with local reactions after intravenous injection of contrast media between November 1994 and December 1996 were studied. Comparison was made with data obtained from a control group of 100 patients with no local reactions who underwent contrast material-enhanced computed tomography (CT). RESULTS: Local reactions were reported in 56 (0.25%) of 22,254 patients who received intravenous injections of iodinated contrast media. Fifty-one patients experienced extravasation, and five patients experienced local irritation in the absence of clinically detectable extravasation. Extravasation occurred during CT (n = 46), urography (n = 4), and venography (n = 1). Contrast material was nonionic in 37 cases and conventional ionic in 14 cases of extravasation. Extravasated volumes exceeded 30 mL in 22 patients and 100 mL in six patients. Forty-five (80%) of 56 patients with local reactions had complete resolution of symptoms within 24 hours. Only four patients had symptoms for more than 48 hours. No surgery was required. Compared with the control group, patients with extravasation were significantly more likely to have been injected with small-bore catheters (21 or 22 gauge) and to have been injected at low or high rates. CONCLUSION: Symptoms of contrast medium extravasation usually resolve quickly. In patients with extravasation, injections are more likely to have been performed with techniques that vary from normal practice.

Cell damage induced by Angiovist-370 and 308nm excimer laser radiation.

BACKGROUND AND OBJECTIVE: Radiographic contrast media containing iodine-labeled organic compounds can be present in the irradiated field during laser angioplasty using 308 nm excimer laser radiation. These compounds absorb light at 308 nm and may undergo photochemical reactions that produce products that damage cells. STUDY DESIGN/MATERIALS AND METHODS: This study was undertaken to determine whether photoproducts that damage human lymphocytes in vitro are formed when Angiovist 370 (AV), a contrast medium containing triiodinated aromatic compounds, is exposed to 308 nm radiation. RESULTS: The absorption spectrum of AV developed a new peak at 360 nm that extended to wavelengths greater than 500 nm when dilute AV solutions were exposed to 308 nm radiation indicating that photoproducts were formed. Irradiating dilute AV solutions above a layer of human lymphocytes caused a dose-dependent decrease in thymidine incorporation using fluence rates between 5.2 x 10(6) and 1.0 x 10(8) W/cm2. Decreased DNA synthesis was independent of the pulse length (10 ns vs. 230 ns) but was lower, at a given dose, when the highest fluence rate was used. Incubation of lymphocytes with preirradiated AV solutions also decreased incorporation of thymidine in a radiation dose-dependent manner. The cell damaging photoproducts in preirradiated AV solutions were unstable; within 15 min, the effectiveness had decreased by approximately 85%. CONCLUSIONS: These results indicate that exposure of AV to 308 nm excimer laser radiation produces photochemical products that damage human cells in vitro.

Nonconvulsive status epilepticus after intravenous contrast medium administration.

PURPOSE: We describe a 52-year-old man with a glioblastoma multiforme who had a prolonged partial seizure immediately after undergoing a computed tomography (CT) scan of the head with intravenous contrast medium. METHODS: Earlier computed tomography (CT) had demonstrated a ring-enhancing hypodense mass. The patient was treated with a regimen of intravenous Tirapazamine and brain irradiation. After CT scan performed on the day of his second hospitalization, the patient became aphasic. EEG showed continuous high-voltage semirhythmic sharp and slow waves in the left posterior temporal and parietal regions consistent with status epilepticus (SE). Intravenous lorazepam and a loading dose of phenytoin were administered. RESULTS: On the next morning, the patient's condition had improved almost to baseline. He had no recurrent seizures. EEG at 2-month follow-up showed no epileptiform discharges. CONCLUSION: This appears to be the first reported case of contrast medium-induced status epilepticus.

[Acute kidney failure related to the use of x-ray contrast agents and indomethacin: the risk factors and mechanisms of its development]. / Ostraia pochechnaia nedostatochnost', sviazannaia s primeneniem rentgenokontrastnykh sredstv i indometatsina: faktory riska i mekhanizmy razvitiia.

7 acute renal failure (ARF) and experiments provided information on ARF induced by radio-opaque substances and indomethacin. The leading mechanism underlying renal failure is supposed to be the spasm of renal afferent arterioles secondary to hypercalcemia, prostaglandin synthesis blockade, activation of renin-angiotensin system and high activity of adenosine.

In vitro histamine release induced by magnetic resonance imaging and iodinated contrast media.

RATIONALE AND OBJECTIVES: To investigate the mechanism of anaphylactoid reactions to contrast media, in vitro histamine release induced by magnetic resonance imaging, and iodinated contrast agents was examined in a dog mastocytoma cell line. METHODS: Two gadolinium (Gd)-based magnetic resonance contrast agents, Gd diethylenetriamine pentaacetic acid (Gd-DTPA), dimeglumine, and Gd-bismorpholide, and two iodinated contrast agents, diatrizoate meglumine and iohexol, were incubated with histamine-containing canine mastocytoma cells. Release of histamine into the supernatant was determined at various contrast-medium concentrations after incubation at 37 degrees C for 30 minutes. RESULTS: Iodinated and Gd-based contrast agents caused release of histamine from mastocytoma cells at similar concentrations (50-150 mM). Mannitol, an osmotic stimulus, caused release of histamine only at concentrations greater than 1,000 mM. CONCLUSIONS: Histamine release from canine mastocytoma cells does not appear to be solely due to osmotic effects, but results from direct stimulation by contrast media. For all agents examined, the concentration at which in vitro histamine release occurs far exceeds the serum contrast media concentration expected in routine clinical application. Direct release of histamine from mast cells does not completely explain the pathogenesis of idiosyncratic anaphylactoid responses to contrast media.

Gastrografin-induced aspiration pneumonia: a lethal complication of computed tomography.

A 43-year-old man with dysphagia and a tendency to aspirate was found to have squamous cell carcinoma of the esophagus. Curative surgery was planned and preoperative computed tomography of the chest and abdomen was ordered. A ward nurse administered Gastrografin according to a "standing" order, 4 hours before the CT was to be done. The patient aspirated about 50 mL of Gastrografin, and went into cardiorespiratory arrest caused by pulmonary edema. He sustained severe brain damage and died. This is a first report of lethal aspiration of Gastrografin, given in preparation for CT. We advise alerting nurses who administer Gastrografin, especially to patients with dysphagia or impaired consciousness about the grave consequences that can result if the contrast agent is aspirated by the patient. We further advise that responsibility for using contrast agents in radiologic procedures be assumed by the radiologist and not by medical house staff.