Triple Contrast Research Articles

A pilot trial of combination therapy with mitoxantrone and interferon beta-1b using monthly gadolinium-enhanced magnetic resonance imaging

To examine the safety of combination therapy with mitoxantrone (MITX) and interferon beta-1b (IFNbeta-1b) in patients with multiple sclerosis (MS) and a high on-therapy relapse rate and enhancing lesions on baseline magnetic resonance imaging (MRI) scan. Ten patients with worsening relapsing remitting or secondary progressive MS were studied using monthly MRI with triple-dose gadolinium contrast. All patients must have been on IFNbeta-1b for at least six months, have at least one enhancing lesion on a screening MRI, at least one relapse on IFNbeta-1b in the six months prior to study entry and be neutralizing antibody negative. Monthly MRI scans using triple dose contrast and a 30-minute delay between contrast administration and scanning were carried out three times over two months to obtain baseline numbers of enhancing lesions each month. At the end of the baseline phase, MITX was administered at 12 mg/m2 (month 3), and 5 mg/m2 at months 4 and 5. Dosing was continued at 5 mg/m2 every third month. Monthly MRI scanning was continued throughout the duration of MITX dosing. The primary outcome measure was the frequency of new enhancing lesions. Secondary outcome measures included relapse rate, and T1 hypointense and T2 lesion burden. Following the addition of MITX to IFNbeta-1b mean enhancing lesion frequency decreased 90% at month 7 (P = 0.008) and enhancing lesion volume decreased by 96% (P = 0.01). Relapse rates decreased 64% (P = 0.004). T2 lesion burden and T1 hypointense lesion burden increased slightly during the baseline phase and decreased following MITX but the difference did not reach statistical significance. There were no serious adverse events on combination therapy and no drop-outs due to toxicity. Total white blood cell count was reduced at 14 days post-MITX infusion but returned to normal levels by day 21. There were no neutropenic fevers and there was no clinically significant elevation of liver function tests. While the number of patients in this study was small, the results suggest that the combination is safe and well tolerated. Disease activity was substantially reduced following the addition of MITX to IFNbeta-1b.

Treatment of Isolated Penetrating Flank Trauma

We present our experience during the past 5 years with isolated penetrating flank trauma. We examined the evaluation process, treatment plan, length of stay, outcome, and complications of patients with isolated penetrating injuries to the flank. There were four patient groups: 1) laparotomy (n = 5); 2) local wound exploration (n = 1); 3) laparoscopy (n = 8); and 4) observation and triple contrast CT scan (n = 9). All patients were male. The mean length of stay was 15 days for group 1, one day for group 2, two days in group 3, and 1.5 days in group 4. Three patients had diaphragmatic injuries, which were repaired laparoscopically. One patient with local wound exploration re-presented with a diaphragm hernia. A negative triple contrast CT scan resulted in no subsequent intervention. There were no missed injuries or complications from CT scan + observation or from diagnostic laparoscopy. We believe that laparoscopy may emerge as a useful adjunct in the treatment of patients with flank trauma. We present an algorithm for the management of penetrating flank trauma.

Triple contrast technique for black blood imaging with double inversion preparation

This work reports on the development of a pulse sequence to simultaneously acquire proton density, T(1), and T(2) weighted images in a single magnetization prepared fast spin echo acquisition. The technique is based upon the application of a magnetization preparation consisting of a global inversion followed by slice-selective 180 degrees and 90 degrees pulses to prepare the signal of specific slices. Slices are acquired in an interleaved manner with time delays appropriate for the desired image contrasts. Data acquisition is repeated for all combinations of slice interleaving covering the region of interest until images from all slice locations have been acquired with all desired image contrasts. The multiple image contrasts obtained with this technique should be useful in applications where discrimination between different types of tissue components is desired, such as in the analysis of plaque in cervical carotid artery disease.

Gunshot wounds of abdomen: evaluation of stable patients with triple-contrast helical CT.

To assess helical computed tomography (CT) with contrast material administered intravenously, orally, and rectally (triple contrast helical CT)) in the prospective evaluation of stable patients with abdominal gunshot wounds in whom there is no clinical indication for immediate exploratory laparotomy. The study was conducted for 19 months. All patients met the following inclusion criteria: age of 16 years or older, hemodynamic stability, no clinical signs of peritoneal irritation, and signed consent to participate. Patients with obvious indications for laparotomy, such as gastrointestinal bleeding or evisceration, were excluded from the study. Forty-seven patients fulfilled the criteria and underwent abdominal triple-contrast helical CT. CT findings were evaluated by one of four radiologists for evidence of peritoneal penetration and injury to solid organs or hollow viscera. Patients were followed up clinically for 13 weeks. CT findings were compared with those at surgery and/or clinical follow-up. CT demonstrated abnormalities in 27 (57%) patients. Laparotomy was performed in 11 (23%) patients; 10 procedures were therapeutic and one was nontherapeutic. The remaining 20 patients had a negative CT scan. These patients were treated conservatively. One injury was missed at CT. For prediction of the need for laparotomy, sensitivity of CT was 96%; specificity, 95%; positive predictive value, 96%; negative predictive value, 95%; and accuracy, 96%. In stable patients with gunshot wounds to the abdomen in whom there is no indication for immediate surgery, triple-contrast helical CT can help reduce the number of cases of unnecessary or nontherapeutic laparotomy (negative laparotomy) and can help identify patients with injuries that may be safely treated without surgery.

Superior mesenteric vein thrombosis following uncomplicated appendectomy

A 20-year-old man presented to the Emergency Department (ED) with a history and physical examination consistent with acute appendicitis. On exploration, a mildy inflamed but unperforated appendix was removed; the adjacent bowel was unremarkable and no other abnormalities were found. The patient was discharged on postoperative day two with minimal incisional and no other abdominal pain. On postoperative day five, he returned to the ED after rapid onset of severe, diffuse, constant abdominal pain. Pain was significantly out of proportion to the examination, suggesting a diagnosis of bowel ischemia or infarction. A triple (oral, rectal, and intravenous) contrast computed tomography (CT) scan was performed (Figure 1). This revealed near-total thrombosis of the superior mesenteric vein (SMV). The small bowel wall was not significantly thickened, suggesting that there was no bowel infarction. No intraabdominal abscess or free fluid was present. The patient was placed on intravenous heparin, antibiotics, and pain medications. The abdominal pain gradually resolved over 3 days and he was advanced to a regular diet and discharged on warfarin therapy. At 3 months follow-up, a repeat CT scan showed no evidence of residual thrombus. Prior to initiation of heparin therapy, blood was drawn for hypercoagulability studies. No abnormalities were found in levels of protein C, protein S, antithrombin III, factor V Leiden, or homocysteine. Complete blood count with manual differential revealed no erythrocytosis, thrombocytosis, significant leukocytosis, or RBC fragmentation consistent with underlying hematologic disease. Studies repeated after cessation of warfarin were also normal. Previous abdominal surgery and hypercoagulable states are the most common conditions associated with superior mesenteric venous thrombosis (1). Portal or SMV thrombosis occurs in 3% of cases of perforated appendicitis but has been described only as sporadic case reports after uncomplicated appendicitis (2). Treatment is that of other causes of mesenteric ischemia, i.e., immediate operation in the presence of peritonitis or intestinal infarction, or fluid resuscitation and anticoagulation if non-operative management is possible (1). This article was written by LCDR Zsolt T. Stockinger, MC, USNR while a fellow at Tulane University training in Trauma Surgery and Surgical Critical Care. The views expressed in this article are those of the author and do not reflect the official policy or position of the Department of the Navy, Department of Defense, nor the U.S. Government.

A pitfall in triple contrast CT of penetrating trauma of the flank

This brief report describes the case of a 20-year-old man who was stabbed in the left flank. He underwent triple contrast helical CT of the abdomen and pelvis that showed a hyperdense focus in the area of the stab wound. This structure was a chip fracture of pelvis, but was misinterpreted as contrast extravasation, and the patient underwent negative exploratory laparotomy.

Bimonthly cranial MRI activity following an isolated monosymptomatic demyelinating syndrome: potential outcome measures for future multiple sclerosis 'prevention' trials.

Patients with characteristic white matter lesions on MR imaging are at increased risk for the subsequent development of clinically definite MS (CDMS) following an isolated, monosymptomatic demyelinating syndrome (IMDS). These MR positive first-onset patients are thus candidates for MS prevention trials. Seven consecutive patients with IMDS and two or more periventricular and/or oval lesions on MR imaging were enrolled into a prospective trial based on serial T2-weighted and enhanced MR imaging at two month intervals for 12 - 15 months. Forty-seven new enhancing lesions were detected with triple dose MR contrast compared to 31 lesions using the standard dose. Four of the seven patients accounted for 98% of all enhancing lesions in this study, while the remaining three patients showed little MRI or clinical disease activity. New T2 lesion counts correlated strongly with enhanced lesion counts (r=0.82 - 0.98). We detected 49 new T2-hyperintense (T2) lesions based on short-interval (2 monthly) follow-up, and 31 new T2-lesions comparing exit and entry examinations. These results suggest several potential MR-based strategies for evaluating first onset patients in a phase III MS prevention trial. Since these patients have a small average T2-lesion load, it is quite easy to visually detect new T2 lesions. As a result, at a bimonthly study interval, T2-weighted lesion analysis is an effective measure of cumulative disease activity, provided high-resolution T2-weighted imaging studies are acquired to quantitate new T2-lesions. Enhanced lesion activity remains an important measure of blood - brain - barrier breakdown and may predict short term MRI and clinical disease activity in IMDS patients.

Role of abdominal computed tomography in the evaluation and management of stab wounds to the back and flank

The purpose of this study was to examine the role of abdominal computed tomography (CT) in the evaluation and management of stab wounds to the back and flank. We retrospectively studied 62 patients with nonsuperficial stab wounds to the back and flank who presented without signs of peritonitis or hemodynamic instability. Twenty-seven patients had conventional CT with oral and intravenous contrast medium administration. Twenty-seven patients had CT with oral, intravenous, and rectal contrast medium, which is called “triple contrast CT” (TCCT). Eight patients had CT with oral and intravenous contrast medium with the addition of air insufflated rectally. Patients with no CT evidence of intra-abdominal injury or with evidence of visceral injury that was considered minor were initially treated with observation. Patients with CT evidence of surgically significant injury received immediate celiotomy. The results of laparotomy and/or patient follow-up were used to determine the sensitivity and specificity of CT for classification of patients into operative or nonoperative categories. For proper classification of patients into operative or nonoperative categories, conventional CT and CT with rectal contrast demonstrated nearly identical sensitivities of 100%, specificities of 96%, and accuracies of 96%. The results were similar for the group that received rectal air. Combining all patients, CT demonstrated a sensitivity of 100%, a specificity of 96%, and an accuracy of 97%. The negative predictive value was 100%, and only 2 of the 62 patients (3.2%) received nontherapeutic laparotomies. CT is useful in the routine management of hemodynamically stable patients with nonsuperficial stab wounds to the back and flank.

Neutron scattering in the ribosome structure

Thermal neutron scattering has become a powerful instrument for studying the ribosome and its components. The application of neutron scattering allowed to establish some principal features of the ribosome structure: non-homogeneous distribution of the RNA and protein within ribosomal particles, the RNA role as a framework in the arrangement and maintenance of the structure of ribosomal particles, and the globular character of ribosomal proteins. The use of selective deuteration of separate ribosomal proteins in combination with the triangulation method revealed mutual spatial arrangement (the 3D-map) of all the ribosomal proteins within the small particle and in the most part of the large ribosomal particle. An essential impact has been made in the structural studies of ribosomes with the development of novel experimental approaches: triple isotopic substitution and spin contrast variation. These approaches with direct interpretation of spherical harmonics provide new possibilities for constructing models of ribosomal particles, opening principally new perspectives for joint use of X-ray synchrotron diffraction in crystals and small-angle neutron scattering in solution.

Diagnosis of injuries after stab wounds to the back and flank.

Historically, patients with deep posterior wounds underwent a formal celiotomy to rule out injury. Currently, we use a policy of selective management. The purpose of this review is to evaluate our experience with selective management to identify potential areas of further improvement. This study includes 203 patients over a 10-year period. By changing from a policy of mandatory exploration to selective management the total celiotomy rate decreased from 100 to 24% and the therapeutic celiotomy rate increased from 15 to 80%. In stable patients, a diagnostic peritoneal lavage should be performed as the initial diagnostic study. When diagnostic peritoneal lavage is negative, triple contrast computed tomography should be performed to evaluate the remaining retroperitoneal structures. Any suggestion of pericolonic extravasation of contrast or air, edema, or hemorrhage must be interpreted as a positive study and prompt consideration for operative exploration.

Laparoscopic-ultrasonographic combined technique for the creation of a neovagina in Mayer-Rokitansky-Kuster-Hauser syndrome

To create a neovagina using a combined laparoscopic and ultrasonographic technique in Mayer-Rokitansky-Kuster-Hauser syndrome by modification of Vecchietti's operation. Case report. Division of Physiopathology of Reproduction, University of Palermo, Palermo, Italy. The advancement of the needle from the pseudohymen, through the vesicorectal space using a triple contrast ultrasonographic technique. The ultrasonographic scanning guides the accurate transit from external genitalia to the peritoneal cavity. This original approach allowed a safe and rapid creation of a neovagina in a case of Mayer-Rokitansky-Kuster-Hauser syndrome.

Is triple contrast computed tomographic scanning useful in the selective management of stab wounds to the back?: McAllister E, Perez M, Albrink MH et al. J Trauma. 1994; 37:401-3

Is triple contrast computed tomographic scanning useful in the selective management of stab wounds to the back?: McAllister E, Perez M, Albrink MH et al. J Trauma. 1994; 37:401-3

Is triple contrast computed tomographic scanning useful in the selective management of stab wounds to the back?

We devised a protocol to prospectively manage stab wounds to the back with the hypothesis that the triple contrast computed tomographic (CT) scan is an effective means of detecting occult injury in these patients. All wounds to the back in hemodynamically stable adults were locally explored. All patients with muscular fascial penetration underwent triple contrast CT scanning utilizing oral, rectal, and IV contrast. Patients did not undergo surgical exploration if their CT scan was interpreted as negative or if the CT scan demonstrated injuries not requiring surgical intervention. Fifty-three patients were entered into the protocol. The time to complete the triple contrast CT scan ranged from 3 to 6 hours at a cost of $1050 for each scan. In 51 patients (96%), the CT scan either had negative findings (n = 31) or showed injuries not requiring exploration (n = 20). These patients did well with nonsurgical management. Two CT scans documented significant injury and led to surgical exploration and therapeutic celiotomies. Although triple contrast CT scanning was able to detect occult injury in patients with stab wounds to the back it did so at considerable cost and the results rarely altered clinical care. Therefore, its routine use in these patients is not recommended.

Simultaneous acquisition of proton density, T1, and T2 images with triple contrast RARE sequence.

A fast multislice sequence that gives proton density (PD)-, T1-, and T2-weighted images simultaneously has been developed. The triple contrast RARE (TCRARE) is based on RARE and uses two interleaved TR intervals to obtain PD-, T1-, and T2-weighted images without spatial misregistration or RF gain mismatch within 2 min. By adding a fat suppression pulse before one of two excitation pulses, it is also possible to obtain an image set with and without fat suppression in a single acquisition.

Proton MR chemical shift imaging using double and triple phase contrast acquisition methods.

Conventional chemical shift magnetic resonance (MR) imaging with the phase contrast technique has a number of limitations with respect to quantitative accuracy. The hypothesis of this study is that the accuracy of phase contrast chemical shift MR may be improved by increasing the number of basis images from two to three. Water and fat images were obtained from phantoms and volunteers with a 1.5 T MR system using double and triple acquisition phase contrast chemical shift methods. Longitudinal relaxation time and relative water and fat content were calculated from these basis images. The T1 relaxation times of the aqueous component of composite phantoms were determined more accurately using the triple acquisition method than with the double acquisition method. In vivo studies demonstrate that the triple acquisition method separated fat and water signals more accurately and showed less field inhomogeneity dependence than the modified double acquisition method. The new method also provided a map of static field magnetic inhomogeneity and tissue magnetic susceptibility. The triple acquisition phase contrast chemical shift imaging technique should improve the prospect for quantitative tissue characterization in clinical MR.

Triple contrast percutaneous nephrocystography and analysis of cyst aspirate

Accumulated experience with triple contrast percutaneous nephrocystography (water-soluble contrast, iophendylate [Pantopaque], and air) in 42 patients with avascular lesions is presented. Diagnostic studies were accomplished in 40 with surgical correlation in 11. Of the 35 patients with intracystic iophendylate, progressive cyst shrinkage was observed in the 29 with adequate x-ray follow up. The reduction in cyst size was attributed to a marked reactive inflammatory proliferative response with fibrosis of the cyst wall which was found in 6 patients after introduction of iophendylate when compared with a control group of 13 others with surgically proved cysts. Intracystic iophendylate may be especially therapeutic in the nonsurgical management of renal cysts associated with pain, calyceal obstruction, and hypertension. The cyst aspirate was analyzed for appearance, culture, cytology, fat content, and multichannel chemistries (SMA). The index accuracy of these combined tests is high although instances of false positives and negatives for tumor are stressed. The nonsurgical diagnosis of renal cystic lesions is incomplete without percutaneous cyst puncture, contrast study, and analysis of cyst aspirate.

Anomalous X-Ray Images of Imperfections in Boron-Diffused Silicon

In X-ray topographs of boron-diffused silicon, an anomalous triple image contrast is observed for straight imperfections along the three direction in (111) wafer. The contast is different from that of dislocation image observed by Borrmann effect of extinction effect. It is found that the imperfections are not simple 60° dislocations but the dislocations accompanied by imperfection of another type and have long range strained region besides the strain due to dislocation. It is concluded that the anomalous contrast is attributed to the dynamical diffraction effect in the strain field composed by the both imperfections.

Pitfalls in Clinical Staging of Bladder Tumors

Errors in clinical staging of bladder carcinoma occur in about 50 per cent of patients. Sources of error include (1) a variable assortment of diagnostic studies performed, (2) inexactitudes inherent in the diagnostic measures employed, (3) insufficient corroboration by surgical and pathologic staging, (4) the lack of a satisfactory means for detecting micrometastases, and (5) a generalized confusion regarding the multiple classifications available for clinical staging. More precise clinical staging will be influential in treatment decision-making and in prognosis. Minimum requirements for clinical staging of the primary tumor currently include complete examination, excretory urography, cystoscopy, bimanual examination under anesthesia, and transurethral resection or biopsy. Polycystography, triple contrast cystograpy and arteriography may be helpful occasionally to document muscle invasion. Pedal lymphangiography and lymphography can in selected cases be helpful in detecting otherwise silent nodal involvement in spite of its inability to demonstrate many primary or regional lymph nodes. Familiarity with the above diagnostic options and the advantages and limitations of each is essential for each physician caring for a patient with bladder carcinoma. Conversion to TNM classification for bladder carcinoma that is similar to that of the UICC seems appropriate (1) because of its more rational approach to extent of involement by primary tumor, lymph node and distant sites, and (2) in order for our western hemisphere urologists to communicate better with our colleagues from around the globe. Such a system is now under consideration by a subcommittee of the American Joint Committee on Staging and End Result Reporting.

Evaluation of triple contrast cyst aspiration in the management of renal masses.

Evaluation of triple contrast cyst aspiration in the management of renal masses.

Study and Diagnosis of Bladder Tumors by Triple Contrast Cystography

Study and Diagnosis of Bladder Tumors by Triple Contrast Cystography