Magnetic iodixanol - a novel contrast agent and its early characterization.

AIMS: Contrast-induced nephropathy is a commonly encountered problem in clinical practice. The purpose of the study was to design and develop a novel contrast agent, which could be used to prevent contrast-induced nephropathy in the future. METHODS: In total, 20-220nm magnetic nanoparticles were conjugated with iodixanol, and their radio-opacity and magnetic properties were assessed thereafter. Scanning electron microscopy pictures were acquired. Thereafter, the nanoparticles conjugate was tested in cell culture (HUVEC cells), and Quantibody® assay was studied after cell treatment in 1:5 dilutions for 48h, compared with control. RESULTS: The conjugate preparation had an adequate radio-opacity. A 4mm magnetic bubble was attached to a bar magnet and the properties were studied. The magnetic bubble maintained its structural integrity in all angles including antigravity position. Scanning electron microscopy showed magnetic nanoparticles in all pictures and the particles are of 100-400nm agglomerates with primary particle sizes of roughly 20nm. 1:5 diluted particles had no effect on secretion of IL-1a, IL-1b, IL-4, IL-10, IL-13 and TNFa. Particles increased secretion of IL-8 from 24h and 48h. Secretion of IFNg was also increased when particles were added to the cells as early as 1h. Likewise, IL-6 was strongly secreted by HUVEC treated with particles from 24h incubation time. In contrast, the secretion of MCP-1 was slightly reduced on HUVEC treated with particles. CONCLUSION: There is potential for a novel iodixanol-magnetic nanoparticle conjugate to be used in cineradiography. Further investigations need to be performed to study its performance in vitro and in vivo.

The acoustic effect of vocal tract adjustments in zebra finches.

Vocal production in songbirds requires the control of the respiratory system, the syrinx as sound source and the vocal tract as acoustic filter. Vocal tract movements consist of beak, tongue and hyoid movements, which change the volume of the oropharyngeal-esophageal cavity (OEC), glottal movements and tracheal length changes. The respective contributions of each movement to filter properties are not completely understood, but the effects of this filtering are thought to be very important for acoustic communication in birds. One of the most striking movements of the upper vocal tract during vocal behavior in songbirds involves the OEC. This study measured the acoustic effect of OEC adjustments in zebra finches by comparing resonance acoustics between an utterance with OEC expansion (calls) and a similar utterance without OEC expansion (respiratory sounds induced by a bilateral syringeal denervation). X-ray cineradiography confirmed the presence of an OEC motor pattern during song and call production, and a custom-built Hall-effect collar system confirmed that OEC expansion movements were not present during respiratory sounds. The spectral emphasis during zebra finch call production ranging between 2.5 and 5 kHz was not present during respiratory sounds, indicating strongly that it can be attributed to the OEC expansion.

[Treatment of hypopharyngeal carcinomas--an institutional analysis of the results of FAR radiochemotherapy, radical resection, and free jejunum flap reconstruction and the indication of neck dissection].

The treatment results of 65 patients with hypopharyngeal carcinomas treated at our institute between 1995 and 2000 were analyzed. In general, concurrent radiochemotherapy (RCT), consisting of intravenous 5-FU injection, intra-muscular vitamin A injection, and radiation (FAR therapy) was used as an initial treatment for advanced hypopharyngeal carcinomas and early hypopharyngeal carcinomas. Tumor responses were evaluated at the time of radiation doses of 30Gy. Patients who showed a complete response (CR) subsequently received curative radiation doses of 60 to 70Gy. Patients who did not show a CR underwent radical surgery consisting of pharyngo-laryngo-cervical esophagectomy, neck dissection for positive cervical nodes and/or the primary tumor sides, and reconstruction using a free jejunum flap. The disease-specific 5-year survival rates were 92%, 55%, 35% and 49% for stage I/II, III, IV and all cases, respectively. Eight out of 9 patients with stage I/II disease who showed a CR after receiving 30Gy of RCT survived with an intact larynx after definitive RCT. All the patients with stage II/III disease who underwent radical surgery after receiving 30Gy of RCT did not have a recurrence, whereas the 5-year survival rate of patients with stage IV disease who underwent RCT and radical surgery was 45%. Seventeen out of 19 patients with clinically negative cervical nodes on the opposite side of their primary tumors showed no nodal metastasis after RCT without neck dissection. This result suggests that elective neck dissection after RCT is not necessary. To improve the treatment results for hypopharyngeal carcinomas, early detection of this disease is prerequisite. In addition, the clinical diagnosis of highly malignant cases and new molecular-targeted therapies based on an analysis of distant metastasis mechanisms should be developed to overcome the poor prognosis of advanced hypopharyngeal carcinomas.

Effect of dietary lipase enzyme on gut morphology, gastric motility, and long-term performance of broiler chicks.

Three experiments were conducted to test a previously described anorexic effect of graded dietary supplements of Pancreatic lipase enzyme on gut structure, gastric motility, and long-term performance of broiler chicks. In Experiment 1, dietary Pancreatic enzyme was used at graded levels of 0, 0.214, 0.429, 0.643, 0.857, and 1.071% to test the effect of this enzyme on gut structure, whereas Experiment 2 was designed to test its effect at 0, 0.268, 0.536, 0.804, 1.071, and 1.339% on gastric motility. The histological examination of the small intestine and a cineradiographic study of birds fed diets supplemented with lipase enzyme failed to detect any difference in gut structure, and there was no apparent adverse effect on gastric motility. Experiment 3 was conducted to test the effect of graded supplements of Pancreatic enzyme on performance of 300 male broiler chicks raised for 6 wk to determine whether the enzyme had any long-term effect on performance characteristics, especially feed intake. Only starter diets (0 to 21 d) were supplemented with 0, 0.375, 0.750, or 1.125% enzyme, and each diet was represented by three replicate pens of 25 male chicks each. Subsequent diets did not contain any enzyme. During the first 3 wk, increased dietary concentration of lipase enzyme caused a linear reduction of feed intake and body weight gain (P < 0.01). At 21 d the percentage weight of the liver was significantly greater with 1.125% enzyme (P < 0.01). However, added enzyme had no effect on 21 to 42 d or 1 to 42 d growth or feed intake (P > 0.05) or on the size of any internal organs examined at 42 d. Pancreatic enzyme has previously been shown to improve fat digestion and increase diet AMEn for young chicks fed animal-vegetable blended fats. These positive effects, however, are associated with marked anorexia, and from the present study, it seems that this effect was not related to physical changes in gut histology or in prolonged digesta transit time.

Chronic stimulation of the left vagal nerve in children: effect on swallowing.

PURPOSE: To learn whether stimulation of the left vagal nerve would influence swallowing. METHODS: Eight children receiving intermittent left vagal nerve stimulation (VNS) for their pharmacoresistant epilepsy underwent barium swallow studies with their generators off, on, and at maximally tolerated settings. RESULTS: Laryngeal penetration of barium was present in three patients without stimulation, and was caused by VNS in one other patient. Aspiration never occurred. CONCLUSIONS: Stimulation of the left vagal nerve under conditions used to treat epilepsy does not cause aspiration.

Surgical correction of submucous cleft palate with Furlow palatoplasty.

Many surgeons have favored using the pharyngeal flap as the primary treatment for the velopharyngeal insufficiency associated with submucous cleft palate. However, the increasing number of reports of sleep apnea and airway compromise as a result pharyngeal flap surgery support the need to eliminate any unnecessary pharyngeal flap surgery. From 1988 to 1993, 35 Chinese submucous cleft palate patients with velopharyngeal insufficiency received surgery. A Furlow palatoplasty was used in 30 patients (3 to 26 years old). The follow-up duration was 9 months to 5 1/2 years. These patients were selected after a thorough study for velopharyngeal insufficiency including intraoral examination, perceptual speech assessment, videonasopharyngoscopy, and/or multiview videofluoroscopy. The criteria for selection included age, intraoral finding of an obviously anterior inserted levator palatine muscle, size of velopharyngeal gap, pattern of velopharyngeal closure, degree of lateral pharyngeal wall movement, and response to biofeedback speech therapy. In general, younger patients with circular or sagittal pattern closure, a velopharyngeal gap less than 5 mm, or good response to biofeedback speech therapy were considered to be the best candidates for a Furlow palatoplasty. The 5 patients who did not fulfill these criteria and whose velopharyngeal function failed to improve on preoperative biofeedback therapy were treated by pharyngeal flap operation. Twenty-nine patients (96.7 percent) achieved competent velopharyngeal function after the Furlow palatoplasty. The procedure corrected the velopharyngeal insufficiency in 3 patients older than 20 years with a velopharyngeal gap of less than 2 mm. The only patient with an unsatisfactory result was a 26-year old woman who had very prominent action of the musculus uvulae before the surgery. The results show that a Furlow palatoplasty can satisfactorily correct velopharyngeal insufficiency in carefully selected submucous cleft palate patients and thus avoid the serious complications of pharyngeal flap surgery.

Influence of cold stimulation on the normal pharyngeal swallow response.

We examined the potential influence of cold stimulation of the anterior tonsillar pillars, before and after topical anesthesia, on the temporal linkage between the oral and pharyngeal components of the swallow. We hypothesized that if elicitation of the pharyngeal swallow were dependent upon stimulation of faucial mucosal receptors this response would be facilitated by cold tactile stimulation and inhibited by topical anesthesia. In 14 healthy volunteers undergoing simultaneous videoradiography and manometry we measured and compared regional transit and clearance times, and the timing of hyoid motion, upper esophageal sphincter relaxation, and opening within the swallow sequence. There was a significant, volume-dependent forward shift in timings of hyoid motion, upper esophageal sphincter (UES) relaxation profile, and opening which were influenced neither by cold stimulation nor topical anesthesia. Regional transit and clearance times and UES coordination were not influenced by cold stimulation. Pharyngeal clearance time was prolonged by tonsillar pillar anesthesia due to earlier arrival of the bolus head at this region (p = 0.002). We conclude that the normal pharyngeal swallow response is neither facilitated nor inhibited by prior cold tactile stimulation or topical anesthesia to the tonsillar pillars, respectively. These observations do not support the hypothesis that elicitation of the pharyngeal swallow response is dependent upon stimulation of mucosal receptors in the tonsillar arches.

Defecography.

Defecography, a dynamic imaging modality, plays an important role in the diagnosis of functional and morphologic abnormalities of the anorectal region. We have here summarized the principle and techniques as well as observations of defecography, with special emphasis on morphologic measurements, clinical relevance, and limitations. The application of MR imaging in examination of anorectal function has also been addressed.

Patient position during cinedefecography. Influence on perineal descent and other measurements.

PURPOSE: This study was undertaken to assess the reproducibility of cinedefecography measurements and abnormal findings between the left lateral decubitus and seated positions. METHODS: Prospective patient evaluation included all patients who had lateral radiographs of the pelvis taken at rest, during squeezing, and pushing in both positions. Anorectal angle, perineal descent, and puborectalis length measurements were calculated for each set of radiographs. Pelvic floor dynamics during evacuation were measured as the changes between rest and pushing. Abnormal findings included both increased dynamic and fixed perineal descent, nonrelaxing puborectalis, and premature evacuation. RESULTS: One hundred five consecutive patients underwent cinedefecography. There were statistically significant differences between the positions with regard to anorectal angle (P < 0.0001), perineal descent (P = 0.0001), and puborectalis length (P = 0.0001). Dynamic changes of the anorectal angle, perineal descent, and puborectalis length were not significantly different (P > 0.05). However, 6 of 22 (27 percent) patients with fecal incontinence had premature evacuation severe enough to impede measurement only when seated (P = 0.05). CONCLUSION: Because of the statistically significant differences between the two positions, centers should always employ the same position for a given diagnostic group.

Early experience with dobutamine stress testing and cardiac cine-tomographic imaging in the elderly: antianginal effects of nifedipine-GITS.

OBJECTIVE: To determine the effects of nifedipine-GITS (GITS = gastrointestinal transport system) on angina and cardiovascular responses to stress-dobutamine infusion, we used ultrafast cine-computed tomography (CT) to assess regional wall motion, myocardial perfusion, and indices of ventricular filling and emptying. DESIGN: Randomized, double-blind placebo-controlled efficacy study after an open-label dose titration phase. SETTING: University of California, San Francisco. PATIENTS: Elderly patients (> 60 years; n = 9:8 male, 1 female) with coronary artery disease by history and diagnostic treadmill or coronary angiography. INTERVENTION: After a 3-week open-label dose-titration phase, eight subjects were randomized to receive either placebo or nifedipine-GITS at the highest tolerated dose for 2 weeks, followed by a crossover to the alternate therapy for 2 weeks. One declined because of singulus in the open-label period. MAIN OUTCOME MEASURES: Symptomatic angina relief (frequency and nitroglycerin consumption), dobutamine stress responses (time to ischemia during dobutamine infusions, cardiac output, cardiac ejection fraction, ventricular segmental wall motion, and perfusion as measured by ultrafast cine-CT), and reported adverse effects. RESULTS: When compared with placebo, nifedipine-GITS administration was associated with less frequent angina and nitroglycerin consumption (NS) and significantly decreased systolic blood pressure. Nifedipine-GITS administration also increased resting supine heart rates. Dobutamine infusions increased heart rate, cardiac output, cardiac ejection fraction, and stroke volume and induced angina symptoms. Neither double product at angina nor systolic indices of cardiac function in response to dobutamine differed between nifedipine-GITS and placebo, although heart rate responses were greater during nifedipine. A trend toward increased peak filling rates was seen during dobutamine stress in the nifedipine-administration period. In most subjects (6/8), perfusion and regional wall motion abnormalities were not visualized on regional wall motion abnormalities were not visualized on either rest or stress cine-CT studies. Edema without congestive heart failure occurred frequently during nifedipine-GITS administration. CONCLUSIONS: These data suggest that (1) dobutamine stress can be used to induce cardiac ischemia in elderly patients with coronary artery disease, (2) nifedipine-GITS provides symptomatic angina relief in elderly patients, (3) peripheral edema is frequent in elderly patients on nifedipine-GITS, and (4) ultrafast computed cine-tomography testing can be used to assess ventricular performance, but current methodology may not detect perfusion or wall motion abnormalities during angina.

Evaluation and treatment of chronic intractable rectal pain--a frustrating endeavor.

A study was undertaken to assess the evaluation and treatment of chronic intractable rectal pain. Sixty consecutive patients, 23 males and 37 females with a mean age of 69 (range, 29-87) years and a mean length of symptoms of 4.5 years, were evaluated by questionnaire, office examination, anal manometry, electromyography, cinedefecography, and pudendal nerve study. In all cases, organic abdominopelvic and anorectal etiologies for the pain were excluded by extensive radiologic and endoscopic evaluation. All patients had failed conservative and medical therapy. Ninety-five percent of patients had one or more associated factors: constipation or dyschezia (57 percent), prior pelvic surgery (43 percent), prior anal surgery (32 percent), prior spinal surgery (8 percent), irritable bowel syndrome (10 percent), or psychiatric disorders (depression or anxiety; 25 percent). Possible etiologies for the pain included levator spasm or anismus in 62 percent, coccygodynia in 8 percent, and pudendal neuropathy in 24 percent of patients. Therapy for pain control included electrogalvanic stimulation (EGS) in 29, biofeedback (BF) in 14, and steroid caudal block (SCB) in 11 patients. Pain control was assessed by an independent observer at a mean of 15 (range, 2-36) months after completion of therapy. Continued successful pain relief was classified by patients as good or excellent after EGS in 38 percent, after BF in 43 percent, and after SCB in 18 percent; overall success was reported by 47 percent of patients. The presence of levator spasm, coccygodynia, or pudendal neuropathy did not influence outcome. The routine use of physiologic investigation of rectal pain may not be justifiable. Moreover, more than half of the patients were refractory to all three therapeutic options used in this study.

Skeletal applications of videofluoroscopy.

The use of skeletal videofluoroscopy is spreading as new applications emerge for coupling the fluoroscope with the video cassette recorder to obtain detailed information on moving anatomy. This review compiles the findings of an extensive literature search and summarizes the current state of videofluoroscopy knowledge. It traces the development of this imaging tool, beginning with cineradiography and its early investigations into cervical spine motion in the 1950s. Videofluoroscopy is presently used to evaluate the entire spine and other areas of the skeletal system, as well as diverse systems throughout the body. Because it is the only imaging technique capable of visualizing actual joint motion in real time, it provides details on movement mechanics not available through other methods. Along with presenting current applications of videofluoroscopy, this review points to future research needs.

The functional radiographic examination of patients with low-back pain: a study of different forms of variations.

Abnormal intervertebral motion has been shown to occur frequently in patients with low-back pain. Various roentgenographic procedures have been used for evaluating normal and abnormal spinal biomechanics. The main aim of this study has been to evaluate the measurement accuracy and the sources of variation in a single-plane functional radiographic study of lumbar intervertebral motion in patients with low-back pain. Analysis of variance was made for intentional and coupled motions in the frontal and sagittal planes, showing least variation in the frontal plane sitting and in the sagittal plane standing. A quantitative reference value of the collective sources of error/variation has been established. Cine-radiographic examinations in the frontal plane were compared with lateral bending roentgenograms to evaluate intermediate stages and extremes of intervertebral motion. A pilot-study was performed indicating that specific manipulative therapy can objectively increase the intersegmental mobility of the lumbar spine.

[Cineradiological study of the activity of sorbiperan on the gallbladder and colon (author's transl)]. / Evaluation ciné-radiologique de l'activité du sorbipéran sur la vésicule biliaire et le côlon.

The activity of sorbiperan was assessed during radiological examinations of 15 patients with hypomobility of the gallbladder, associated in some cases with atonic dyspepsia, and 25 cases of spastic colon with constipation and/or diarrhea due to diverticulosis, dolichocolon, sigmoiditis, or parasitosis. Patients with gallbladder dysfunction were examined radiologically before and after oral administration of 20 to 40 ml of sorbiperan, the dose varying as a function of bodyweight. In 3 patients, the hypermobility of the gallbladder provoked by this agent was greater than that observed with all usually employed products, in 11 cases the cholagogue produced an excellent effect, while in one case there was no observed effect. Patients with colitis were administered a barium enemea, and an initial series of films were taken. These were repeated after addition of 80 ml of sorbiperan to the same enema. Total, rapid evacuation of the colon was observed in 8 cases, while in 15 cases it was of excellent quality. No effect was noted in 2 cases. Sorbiperan provokes effective contractions of the gallbladder, favours sphincter of Oddi dynamics, increases motility of all digestive tract segments, and very significantly accelerates gastro-entero-colic peristalsis. Tolerance was excellent.

Long-term intravaginal electrical stimulation in urge and stress incontinence.

Using a new device for intravaginal electrical stimulation (IVS), 24 women with pure stress incontinence, mixed urge and stress incontinence or urge incontinence due to detrusor instability, were treated. To minimize mechanical discomfort, the electrode carrier was made of flexible material and inflatable. Furthermore, this design facilitated fixed, constant positioning of the electrodes at individually tested sites to produce maximum response at voltage well tolerated by the patient. The stimulation frequency was adjusted to suit the cause of incontinence: 20 to 50 Hz in stress incontinence, 10 Hz detrusor instability. The electrode carrier was well accepted. Seven of the 9 patients with pure stress incontinence became continent during IVS. Three of them have so far remained continent for 2 to 8 months without IVS. The 15 patients with detrusor instability or mixed incontinence were all free from symptoms after IVS for more than 3 months. Two of them have remained cured for more than 3 months after they had stopped IVS.

Normal and abnormal motility of the stomach.

The analysis of gastric motility makes possible the distinction between purely anatomic changes and those of a functional nature with or without associated morphologic alterations. Hence, through evaluation of gastric and duodenal motor function contributes significantly to the radiographic examination of the upper gastrointestinal tract.