Koichi Yabunaka

Method for detection of aspiration based on B-mode video ultrasonography

In this study, we aimed to develop a new method for detection of aspiration based on B-mode video ultrasonography and to evaluate its performance. To detect aspirated boluses by B-mode video ultrasonography in patients with dysphagia, we placed a linear array transducer above the thyroid cartilage and observed the area around the vocal folds. Forty-two ultrasonographic measurements were obtained from 17 patients with dysphagia who also underwent videofluoroscopy or videoendoscopy measurements at the same time. Aspirated boluses were observed in B-mode video ultrasonographic images as hyperechoic, long, narrow objects that passed through the vocal folds beneath the anterior wall of the trachea, with movement different from that of the surrounding structure. The sensitivity of aspiration detection was 0.64, and the specificity was 0.84. This newly developed detection method will enable patients with dysphagia to receive appropriate daily swallowing care.

Ultrasonographic diagnosis of advanced colorectal cancer.

We investigated the efficacy of transabdominal ultrasonography for the diagnosis of advanced colorectal cancer. Colonic examination by colonoscopy, barium study, or surgery was carried out in our institution on 1579 patients during the past 5 years. This study focused on 1564 of these patients, 15 who has been diagnosed with colorectal cancer before ultrasound examination having been excluded. The results included 51 ultrasound-positive cases, 9 ultrasound-false-positive cases, 1476 ultrasound-negative cases, and 28 ultrasound-false-negative cases. Sensitivity was 64.6 percent and specificity was 99.6 percent. Of the 28 ultrasound-false-negative cases, the lesion was detected in the ascending colon in 2, in the transverse colon in 6, in the descending colon in 1, in the sigmoid colon in 3, and in the rectum in 16. Obstruction and dilatation suggested colorectal cancer in 3 cases, which were thus classified as ultrasound-negative when no tumors were detected. Sensitivity was investigated by site. Sensitivity was lowest at 30.4 percent in rectal cancer, but was 78.6 percent in colon cancer, exclusive of rectal cancer. Laboratory findings and clinical symptoms which were suggestive of colorectal cancer were used as information before ultrasound examination was performed. Sensitivity of examinations carried out on examinees on whom prior information was available and on those on whom there was no information did not differ significantly. Furthermore, ultrasound was thought to detect approximately 65 percent of advanced colorectal cancers when it was used aggressively to investigate the large intestine. Ultrasound was thus considered effective for detecting advanced colorectal cancer.

Using Ultrasonography for Vessel Diameter Assessment to Prevent Infiltration.

Small veins are a risk factor for infiltration. However, there are no data regarding the ideal vein diameter for preventing infiltration. Using ultrasound, vessel diameter and calculated ratios of the vessel diameter to the catheter gauge were measured. The relationship between the ratio and infiltration was assessed to establish a cutoff point. The mean ratio of the infiltration group was significantly smaller than that of the no-infiltration group (P < .01), and the ratio was an independent risk factor according to the multivariable analysis. The ratio of 3.3 was determined to be the cutoff point that enables health care professionals to identify veins appropriately.

Low-temperature infiltration identified using infrared thermography in patients with subcutaneous edema revealed ultrasonographically: A case report.

Infiltration is a frequent complication of infusion therapy. We previously demonstrated the usefulness of infrared thermography as an objective method of detecting infiltration in healthy people. However, whether thermography can detect infiltration in clinical settings remains unknown. Therefore, we report two cases where thermography was useful in detecting infiltration at puncture sites. In both cases, tissue changes were verified ultrasonographically. The patients were a 56-year-old male with cholangitis and a 76-year-old female with hepatoma. In both cases, infiltration symptoms such as swelling and erythema occurred one day after the insertion of a peripheral intravenous catheter. Thermographic images from both patients revealed low-temperature areas spreading from the puncture sites; however, these changes were not observed in other patients. The temperature difference between the low-temperature areas and their surrounding skin surface exceeded 1.0°C. Concurrently, ultrasound images revealed that tissues surrounding the vein had a cobblestone appearance, indicating edema. In both patients, subcutaneous tissue changes suggested infiltration and both had low-temperature areas spreading from the puncture sites. Thus, subcutaneous edema may indicate infusion leakage, resulting in a decrease in the temperature of the associated skin surface. These cases suggest that infrared thermography is an effective method of objectively and noninvasively detecting infiltration.

Sonographic Visualization of Fecal Loading in Adults: Comparison With Computed Tomography

The aim of this study was to compare ultrasonographic assessment of fecal loading in adults with that of computed tomography. Ultrasonography (US) was performed on 43 adult patients immediately after abdominal computed tomography images had identified fecal loading in their colons. In 18 of 43 patients (haustrations-visualized cases), fecal loading was detected as crescent-shaped acoustic shadows associated with haustrations behind the strong echoes off the colon wall. In the remaining 25 patients (haustrations-not-visualized cases), fecal loading was detected as attenuating echoes with multiple high echoic spots behind weak high echoes off the colon wall in 17 patients and similar to those seen in the haustrations-visualized cases but without haustrations in 8 patients. US can be used for qualitative assessment of fecal loading in the colon. This new technique is simple and noninvasive and can be used concomitantly with physical examination to assess severity of constipation.

Ultrasonographic follow-up of functional chronic constipation in adults: A report of two cases

Chronic constipation is a disorder frequently encountered in clinical practice. Here, we describe the use of ultrasonography as a new approach to the follow-up of adult patients with functional chronic constipation. Specifically, we report two cases of functional chronic constipation: fecal retention in the rectum and not fecal retention in the rectum. In the not fecal retention in the rectum patient, ultrasonography showed no evidence of fecal retention in the rectum, including no rectal fecaloma, whereas in the fecal retention in the rectum patient, fecal retention in the rectum was clearly recognized. Moreover, ultrasonography can guide the choice of laxative, enema, or appropriate manual maneuver to treat chronic constipation. As a simple and noninvasive method for assessing functional chronic constipation in adults, ultrasonography not only provides important clinical information but can also aid in determining the location of fecal retention.

Detecting pharyngeal post-swallow residue by ultrasound examination: a case series.

AIMS Prevention of aspiration pneumonia is a great concern in the era of global aging. The assessment of pharyngeal post-swallow residue is important because remaining food and liquid in the pharyngeal area has a possibility of flowing into the lower airway which can cause aspiration pneumonia. Ultrasound examination has been recently used to assess swallowing disorders because of its noninvasiveness. The aim of this study was to investigate the performance for detecting pharyngeal post-swallow residue using an ultrasound examination by comparing with those using a fiberoptic endoscopic evaluation of a swallowing study as a reference. MATERIAL AND METHODS A linear array transducer attached to the thyroid cartilage to visualize the vocal folds in the sagittal plane. The pharyngeal post-swallow residue in the ultrasound movie was interpreted as a misty hyperechoic area above the vocal folds that remained after swallowing. Nineteen ultrasound images simultaneously obtained with fiberoptic endoscopic evaluation of swallowing study images from nine participants (eight men) with a median age of 70 years at a dysphagia outpatient clinic were analyzed by the montage of swallowing examinations. RESULTS Misty hyperechoic areas above the vocal folds that remained after swallowing were detected in 10 ultrasound images. Eight US images out of ten correctly detected pharyngeal post-swallow residue. The sensitivity for detecting pharyngeal post-swallow residue of 19 images from nine participants by US examination was 62%, and the specificity was 67%. CONCLUSIONS The proposed detection method of pharyngeal post-swallow residue by ultrasound examination enabled the real-time assessment for swallowing of people with dysphagia. Ultrasound assessment-based daily swallowing care which detects pharyngeal residue will be useful for preventing aspiration pneumonia.

Videofluoroscopy-guided balloon dilatation for treatment of severe pharyngeal dysphagia.

Balloon dilatation is a widely accepted technique in the management of esophageal and other types of gastrointestinal strictures, but it is rarely used for the treatment of pharyngeal dysphagia. Therefore, the aim of our prospective study was to evaluate the use of videofluoroscopy-guided balloon dilatation (VGBD) for the treatment of severe pharyngeal dysphagia. The study included 32 stroke patients who had been diagnosed with oral and/or pharyngeal dysphagia. All patients underwent dilatation of the esophageal inlet using a balloon catheter under videofluoroscopic guidance during one or more sessions. Following esophageal dilatation, manual feeding was provided twice weekly. VGBD was effective in 10 out of 32 patients; however, the remaining 22 patients were unable to attempt oral food consumption because aspiration was not completely resolved on videofluoroscopy. According to this case series, VGBD may provide treatment for patients with severe pharyngeal dysphagia, who have not consumed food orally for a long period of time.

Improved detection of gastric cancer during screening by additional radiographs as judged necessary by the radiographer

PurposeThe aim of this study was to determine whether additional radiographs, as judged necessary by the radiographer, improves cancer detection during gastric cancer screening.Materials and methodsWe analyzed 144 gastric cancer cases among 137 744 individuals who underwent X-ray screening for gastric cancer. Radiographs were obtained by 17 radiographers at a screening center in Japan from April 2004 to March 2008. Additional radiographs were taken based on the radiographer’s judgment in cases of suspected cancer. During double-blind reinterpretation of the cancer case radiographs by two radiologists, we determined the number of cancer cases that were detected by standard radiographs alone. We next determined the number of cancer cases detected using both standard radiographs and additional radiographs.ResultsCompared to the number of cancer cases detected with standard radiographs alone (120 cases detected, 24 cases undetected), the number of cancer cases detected with both standard and additional radiographs (137 cases detected, 7 cases undetected) significantly increased (17 cases; P < 0.001, McNemar test).ConclusionWe found that taking additional radiographs, when judged necessary by the radiographer during radiographic gastric cancer screening, improves cancer detection.

Sonographic analysis of hyoid bone movement during swallowing

Purpose: Videofluoroscopy is generally considered a “gold standard” technique; however t technique exposes subjects to radiation. Ultrasonography is applied widely in clinical practice because of low cost, safety of the technique, and absence of radiation exposure. The aim of this study was to evaluate hyoid bone movement trajectories during swallowing in healthy subjects using ultrasonography.Subject and Methods: Data were obtained from 15 healthy volunteers (mean age: 34.9± 9.3).The subjects were divided into 3 groups: 5 subjects in their 20s, 5 subjects in their 30s and 5 subjects in their 40s. The subjects were examined while sitting in an upright position, with the back against a wall to control movement. The transducer was placed in a longitudinal scan above the larynx. The hyoid bone was identified on the scan as a high echoic area with posterior acoustic shadow. Then, the subjects swallowed 5 mL of mineral water, with a measurement frequency of 5 times. The digital-ultrasonographic recordings were viewed at 30 frames/s for 3 seconds. Results: The movement was divided into 4 phases: A, slowly ascending phase; B, rapidly ascending phase; C, temporary pause phase (position of maximum rise); D, rapid and slow descending shifts toward the resting position phase. We easily visualized the hyoid bone trajectory using ultrasonography. In all cases, ultrasonographic analysis of the hyoid bone was confirmed to have a similar trajectory as determined with videofluoroscopy. Ultrasonography can accurately determine swallowing duration and trajectory of hyoid bone movement. There was a significant difference in swallowing duration between the 20s groups and 30s groups and between the 20s groups and 40s groups (P < 0.05). However, the difference between the 30s group and 40s group was not significant (P=0.87).Conclusion: The results show that the dynamic phase image of the hyoid bone movement can be revealed by ultrasonographic visualization.