Detection of colorectal carcinoma on double contrast barium enema when double reporting is routinely performed: an audit of current practice

PURPOSE

To determine the sensitivity of double contrast barium enema (DCBE) in the detection of colorectal carcinoma (CRC) when double reporting is routinely performed.

METHOD AND MATERIALS

Over a 1-year period all patients with a diagnosis of CRC within a large teaching hospital were identified. Using computer records, any patient with CRC who had had a DCBE within 5 years of diagnosis was identified. During this time period all DCBE were double reported by the radiographer or radiology trainee who performed the enema and by a consultant radiologist specializing in gastrointestinal radiology.

RESULTS

Over the 1-year period 169 patients were identified with a diagnosis of CRC. Seventy patients had had a DCBE within the preceding 5 years. Sixty-four patients had had CRC diagnosed on the DCBE. One patient had a sessile polyp diagnosed, which was removed at colonoscopy and found to be an invasive adenocarcinoma. In five cases (7%) the CRC was not diagnosed on DCBE. In three cases the lesions could be seen retrospectively, in one case the lesion could not be seen and in one case the examination had been incomplete.

CONCLUSION

In our series the miss-rate for CRC was 7%. Previous studies have shown miss-rates of 15-24%. These studies have not routinely employed double reporting. Our results suggest that double reporting of DCBE significantly reduces the miss-rate and that this reduction is due to fewer perceptive errors.

Who should be performing routine abdominal ultrasound? A prospective double-blind study comparing the accuracy of radiologist and radiographer

AIM

To compare the accuracy of radiographers and radiologists in routine abdominal ultrasound.

MATERIALS AND METHODS

One hundred consecutive patients attending for routine abdominal ultrasound were included. Each patient was examined by both a radiographer and radiologist. Both operators noted their findings and wrote a concluding report without conferring. Reports were compared. Where there was disagreement the patient was either re-examined by another radiologist or had further investigation.

RESULTS

Of 100 patients, 52 were men and 48 were women. The age range was 19-88 years (median 52 years). Thirty-seven patients had renal tract ultrasound, one had an aortic ultrasound and 62 had general upper abdominal ultrasound. In 44 cases both operators reported the examination as normal. In 49 cases both operators reported the examinations as abnormal and there was complete agreement between the operators. In seven cases there was not complete agreement between operators. Three of these disagreements were considered minor and four major. In three of the seven cases the radiographer was correct, and in four the radiologist was correct.

CONCLUSION

Experienced radiographers and radiologists are highly accurate in performing and interpreting routine abdominal sonography. Both operators missed a small minority of abnormalities. There was no statistically significant difference in the accuracy of radiographers and radiologist.

Plexiform neurofibroma of the small bowel infiltrated with metastatic adenocarcinoma

Neurofibromatosis Type 1 (NF1) is not classically associated with gastrointestinal manifestations although these patients are at increased risk of several GI complications. We describe the ultrasound, CT and barium findings in a patient with NF1 who had a huge benign plexiform neurofibroma of the ileum that was infiltrated with metastatic adenocarcinoma.

Air versus carbon dioxide insufflation in double contrast barium enemas: the role of active gaseous drainage

Air has been traditionally used as the negative contrast agent in double contrast barium enema (DCBE) examinations, but causes abdominal pain in the 24 h following the procedure. The frequency of post-procedural pain is less when carbon dioxide (CO2) is used as the negative contrast agent. We evaluated patients following DCBE examinations (using either air or CO2) by means of a questionnaire, to determine whether active drainage of gas altered the post-procedural pain. There was no difference in the pain experienced in the groups receiving CO2 with either active or passive drainage, or in the group receiving air with active drainage. Compared with the other groups there was a significantly higher incidence and severity of pain in the group receiving air and passive drainage. We conclude that active drainage of air following a DCBE examination is as effective as using CO2 in reducing post-procedural pain and swelling.

The effect of size and shape of tablets on their esophageal transit

The esophageal transit times of small- and medium-sized barium sulfate tablets were measured using x-ray fluoroscopy in 50 patients after swallowing while in both erect and supine positions with a 15-mL drink, and the esophageal transit times of large round and oval barium sulfate tablets were similarly measured in 25 patients. When tablets were swallowed by subjects who were standing, no difference was found between the transit times of small and medium tablets, but large oval tablets had significantly shorter times than did large round tablets (P less than .04). The transit times of both small and medium tablets were significantly shorter than those of oval (P less than .05) and large round tablets (P less than .02). Retention of large oval and round tablets in the esophagus occurred in 20% of patients after swallowing while in the standing position. No medium-sized tablet was retained, but in 4% of patients, a small tablet remained in the esophagus. Tablets that were retained in the esophagus remained there for five minutes, when they were washed down by a further drink. When tablets were swallowed in the lying position, no significant differences in transit times were found between any of the four tablets. Retention of tablets within the esophagus occurred in over 60% of patients with all four tablets after ingestion while in the supine position. Tablets stuck mainly in the lower esophagus above the lower esophageal sphincter, but after swallowing in the standing position, a significant proportion (33% [P less than .01]) stuck in the upper esophagus.(ABSTRACT TRUNCATED AT 250 WORDS)

Oesophageal function tests: are they of value?

Oesophageal function was assessed in 15 unselected control patients, eight patients with systemic sclerosis, 10 diabetics with autonomic neuropathy and 24 diabetic controls, by water bolus transit time derived from oesophageal scintigraphy, barium swallow and by timing the transit of a barium sulphate-filled capsule through the oesophagus. Water transit times and capsule transit times were significantly prolonged in patients with systemic sclerosis and diabetics with autonomic neuropathy, compared with controls. Barium swallow was abnormal in seven of eight patients with systemic sclerosis, whereas water transit time was abnormal in all eight and capsule transit time was abnormal in six of seven. Nine of 10 patients with diabetic autonomic neuropathy had abnormal barium swallows and water transit times but all 10 had prolonged capsule transit times. Eleven of 24 diabetic controls had abnormal barium swallows and water transit times, but 21 had abnormally prolonged capsule transit times. Six of 15 controls had abnormal barium swallows, four had abnormal water transit times and 12 had abnormal capsule transit times. In conclusion, water and capsule transit times are sensitive tests of oesophageal function and are as effective as barium swallow in detecting oesophageal motility disorders associated with systemic sclerosis and diabetic autonomic neuropathy. Capsule transit time is cheaper, involves a smaller radiation exposure than oesophageal scintigraphy and may be more sensitive.

Oesophageal function in diabetes mellitus and its association with autonomic neuropathy

We have evaluated oesophageal function in 34 diabetics and in 16 non-diabetic controls by a timed bolus transit method derived from dynamic oesophageal scintiscans (water transit time: WTT) and barium swallow. The diabetics were screened for autonomic neuropathy using standard cardiovascular responses and 10 patients were classified as abnormal. WTT was significantly prolonged in autonomic neuropaths compared with other diabetics (p less than 0.01) and controls (p less than 0.001). Abnormal peristalsis on barium swallow was seen more frequently in autonomic neuropaths (9/10) than in other diabetics (11/24, p less than 0.002). WTTs from all diabetic patients correlated with abnormal heart rate responses at rest (Rs = - 0.49, p less than 0.005), on deep inspiration (Rs = -0.48, p less than 0.005), and on standing (Rs = -0.39, p less than 0.025) but not with the Valsalva manoeuvre. A weaker correlation was found between the postural fall in blood pressure (Rs = 0.3, p less than 0.05). Diabetics with autonomic neuropathy frequently have asymptomatic oesophageal dysfunction which may result from a vagal neuropathy in view of its association with abnormalities of vagally mediated cardiovascular responses.

The effect of formulation on oesophageal transit

The oesophageal transit of barium sulphate in small or large, heavy or light capsules or film coated and plain oval tablets was measured during fluoroscopy in five separate studies involving 175 subjects. Transit of large, but not small capsules was significantly faster than plain oval tablets in both erect and supine subjects (P less than 0.05). Heavy large capsules entered the stomach in all subjects within 20 s, whereas in all other studies some subjects retained dosage forms in the oesophagus for over 5 min. The transit of heavy capsules was significantly faster than light capsules in erect subjects (P less than 0.0005). Light capsules tended to have faster transit times than heavy capsules in the supine position. Film coating significantly enhanced oval tablet transit in erect (P less than 0.00003) and supine subjects (P less than 0.05). When large capsules of equal weight but less dense than film coated oval tablets were directly compared, the tablet transit was significantly superior in the erect subjects (P less than 0.0001). In supine subjects the transit of the light capsule was significantly faster (P less than 0.005). It is concluded that different drug formulations can have significant effects on oesophageal transit, and hence on the development of drug induced oesophageal ulceration.

Effect of left atrial size on the oesophageal transit of capsules

The oesophageal transit time of barium sulphate capsules was measured using X ray fluoroscopy in 20 patients with mitral valve disease and 12 control patients in the erect and supine positions when swallowed with both 15 ml and 60 ml of water. An erect barium swallow was performed, and from a lateral radiograph the area of indentation of the oesophagus caused by the cardiac impression was measured. Left atrial diameter was derived from M mode echocardiography. In 19 patients with mitral valve disease one or more capsules remained in the oesophagus for five minutes and disintegrated there, whereas this occurred in only six control patients. Capsule transit time was significantly slower in the study patients than in the control patients in the supine position with 15 ml water. There was a significant correlation between the area of indentation and mean capsule transit time and supine 15 ml transit time. The area of indentation closely correlated with the left atrial diameter. When capsules were delayed in the oesophagus, this occurred mainly at the level of the left atrial impression in the study patients and at the lower oesophageal sphincter in the control patients. Patients with mitral valve disease are more likely than control patients to have delayed oesophageal transit of capsules because of the anatomical deformity caused by enlargement of the left atrium.

The effect of glucagon on the swallowing of capsules

Glucagon (0.3 mg) given intravenously to 45 patients with normal oesophageal motility significantly reduced oesophageal transit of hard gelatin capsules when swallowed in the supine position with 15 ml water, compared to an age/sex matched group. This is taken to represent an effect on oesophageal peristalsis which has not previously been recognised.

Strictures and other late complications of neonatal necrotising enterocolitis

Eighty infants have been treated for neonatal necrotising enterocolitis within a period of five years. Twenty-five per cent developed strictures of the small or large intestine. Four cases of atresia including two with multiple cyst formation were seen. Four patients developed severe malabsorption requiring hyperalimentation with slow recovery of small bowel function in two survivors. The radiological features of these complications is illustrated and the role of radiology in the management of these patients is discussed.