A comparison of sonographic examinations for trauma performed by surgeons and radiologists

BACKGROUND: It has been demonstrated that surgeons and surgery residents, trained in the focused abdominal sonographic examination, are able to accurately and reliably evaluate trauma patients. Despite this, radiologists have objected to surgeon-performed sonography for several reasons. We set out to compare the accuracy of sonographic examinations performed by surgery residents and radiologists. METHODS: A retrospective review of medical records of all trauma patients who received focused ultrasound examinations from January 1, 1995, through June 30, 1996, at one of two American College of Surgeons-verified Level I trauma centers in the same city was undertaken. Ultrasound examinations were performed by surgery residents at trauma center A (TCA) and by radiologists or radiology residents at trauma center B (TCB). Findings for each patient were compared with the results of computed tomography, diagnostic peritoneal lavage, operative exploration, or observation. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were calculated for each group of patients. Comparison of patient charges for the trauma ultrasound examinations at each of the trauma centers was also made. RESULTS: Patient populations at the two centers were similar except that the mean Injury Severity Score at TCB was higher than at TCA (11.74 vs. 9.6). Sensitivity, specificity, accuracy, or negative predictive value were not significantly different between the two cohorts. A significantly lower positive predictive value for examinations performed by surgery residents was noted and attributed to a lower threshold of the surgery residents to confirm their findings by computed tomography. Billing data revealed that the average charge for trauma sonography by radiologists (TCB) was $406.30. At TCA, trauma sonography did not generate a specific charge; however, a $20.00 sum was added to the trauma activation fee to cover ultrasound machine maintenance and supplies. CONCLUSION: Focused ultrasound examination in the trauma suite can be as safely and accurately performed by surgery residents as by radiologists and radiology residents and should be a routine part of the initial trauma evaluation process.     

Salt-sensitive hypertension induced by sensory denervation: introduction of a new model

OBJECTIVE: To determine whether surgeons and residents with minimal training can evaluate accurately emergency ultrasound (US) examinations compared with radiologists for blunt abdominal trauma. METHODS: Over 7 months, we conducted a prospective study comparing the evaluation of emergency US for blunt abdominal trauma by surgeons and attending radiologists. US readings from the surgical team and the radiologists were correlated with outcome. RESULTS: One hundred-twelve patients were included in the study. Ninety-two patients had an US read as negative by the surgical and radiology services with no subsequent injuries identified. Eighteen patients had an US deemed positive by the surgical service and radiologists. Injuries were confirmed in this group by operation or computed tomography. One patient had an US deemed positive by the surgical team and subsequently negative by the radiologist. A diagnostic peritoneal lavage was performed which was negative. Another patient had an US interpreted as negative by the surgical evaluator and positive by the radiologist. Exploratory laparotomy was negative for intraabdominal hemorrhage or organ injury. Overall results reveal an accuracy on US reading of 99% for the surgical team and 99% for the attending radiologists. CONCLUSION: Surgeons and surgical residents at different levels of training can accurately interpret emergency ultrasound examinations for blunt trauma from the real-time images, at a level comparable to attending radiologists.     

An audit of a radiographer based ultrasound service

A general ultrasound service has evolved over several years. Radiographers undertake the general ultrasound lists, and show the request card and the hard copy films to a radiologist prior to the patient leaving the department. Whilst it is generally accepted for radiographers to carry the burden of obstetric scanning, this is less so for general work. This audit is of a sample of 100 patients out of the general ultrasound lists. These patients underwent the standard service examination by a radiographer and subsequent report by the radiologist. They also had a separate examination and report by an independent radiologist. 42 patients were agreed to have normal findings. 75 diagnoses or observations were made in the remaining 58 patients. Discrepancies arose between the two limbs of the audit in 20 of the observations. Review of the hard copy films and repeat scanning of patients where necessary identified one relevant error by the auditing radiologist and three relevant errors by the standard service. Whilst errors are made both by radiologists and radiographers, it is concluded that the existing radiographer based ultrasound service provides a satisfactory level of accuracy.     

Added copper filtration in digital paediatric double-contrast colon examinations: effects on radiation dose and image quality

Paediatric double-contrast barium enema examinations are usually performed at high tube voltage, 102-105 kV. The aim of this study was to investigate how much the effective dose to the child could be reduced by increasing the X-ray energy further by adding copper filter in the beam, and if this dose reduction could be achieved without endangering image quality. Organ doses to an anthropomorphic phantom simulating a 1-year-old child was measured using thermoluminescence dosimetry for assessment of the effective dose and this value was compared with the energy imparted which was obtained from kerma-area product measurements. To verify that the image quality achieved with this added filtration was still diagnostically acceptable, the study included 15 patient examinations. Since the increased X-ray energy will most probably affect low-contrast objects, image quality was also evaluated with two different phantoms containing low-contrast objects. Effective dose for a complete examination can be decreased 44 % and energy imparted 77 % when a 0.3-mm copper filter is inserted in the beam at tube voltage 102 kV. The patient study did not show any significant deterioration of image quality, whereas phantom measurements of contrast-detail resolution and signal-to-noise ratio was marginally impaired by the added copper filtration. This technique is now in clinical practice for paediatric colon examinations.     

The misdiagnosis of epilepsy: findings of a population study

The aim of the study was to evaluate reasons for anti-HIV testing among persons admitted to Outpatient Counseling Unit. Serum examination for antibodies against HIV were performed in 389 persons during 8 years of the Unit activity. The most frequently it was analysed in intravenous drug users. However there are still many persons who are urged for this analysis before invasive medical procedures. Knowledge on HIV/AIDS in Poland seems to remain on the very low level in public as well as in medical staff.     

Pelvic and perineal complications of Crohn's disease: assessment using magnetic resonance imaging

This study evaluated the role of magnetic resonance imaging (MRI) in the demonstration of the pelvic and perianal complications of Crohn's disease. Twenty five patients with active Crohn's disease were studied (12 male; mean age 41.1 years). MRI examinations were performed using a 1.5 Tesla system, within 14 days after clinical assessment. T1 and T2 weighted fast spin echo sequences in two or three orthogonal planes were performed, with fat suppression in some cases. The MRI results were correlated with surgical and clinical findings. In 16 patients, cutaneous, deep perineal or enterovesical fistulas or abscesses were diagnosed at MRI which showed close correlation with findings at examination under anaesthetic. In eight patients no fistulas or abscesses were seen at MRI nor was there any evidence of complications on clinical examination and flexible sigmoidoscopy. There was one false negative examination in a patient who had a colovesical fistula. In conclusion, MRI can accurately show the pelvic and perineal complications of Crohn's disease and may render examination under anaesthetic unnecessary.     

Utility of daily head ultrasonography for infants on extracorporeal membrane oxygenation

BACKGROUND/PURPOSE: Intracranial hemorrhage (ICH) is a major concern during extracorporeal membrane oxygenation (ECMO). Daily cranial ultrasonography has been used by many ECMO centers as a diagnostic tool for both detecting and following ICH while infants are on bypass. The purpose of this patient review was to look at the usefulness of performing daily cranial ultrasonography (HUS) in infants on ECMO in detecting intraventricular hemorrhage of a magnitude sufficient to alter patient treatment. METHODS: The authors reviewed retrospectively all of the records of all neonates treated with ECMO at the Hermann Children's Hospital, Wilford Hall USAF Medical Center, Cincinnati Children's Hospital, The University of Texas Medical Branch at Galveston, and Texas Children's Hospital between February 1986 to March 1995. Two hundred ninety-eight patients were placed on ECMO during this period. All patients had HUS before, and daily while on ECMO, and all were reviewed by the staff radiologists. A total of 2,518 HUS examinations were performed. RESULTS: Fifty-two of 298 patients (17.5%) had an intraventricular hemorrhage seen on ultrasound scan. Nine of 52 patients (17.3%) had an ICH seen on the initial HUS examination before ECMO, all of which were grade I, and 43 of 52 patients (82.7%) had ICH while on ECMO. Of these ICH, 15 were grade I, 10 were grade II, 10 were grade III, and eight were grade IV. Forty of these ICH (93%) were diagnosed by HUS during the first 5 days of the ECMO course. Seven hundred eighty-six HUS were performed after day 5, at an estimated cost of $300,000 to $450,000 (charges), demonstrating three new intraventricular hemorrhages, one grade I, and one grade IV on day 7 and one grade I on day 8. Eight patients were taken off ECMO because of ICH diagnosed within the first 5 days. One patient was taken off ECMO because of ICH diagnosed after 5 days. This patient had clinical symptoms suggestive of ICH. CONCLUSIONS: Almost all ICH occur during the first 5 days of an ECMO course. Unless there is a clinical suspicion, it is not cost effective to perform HUS after the fifth day on ECMO, because subsequent HUS examinations are unlikely to yield information significant enough to alter management.     

Adolescent outcomes of childhood disorders: the consequences of severity and impairment

The clinical use of positron emission tomography (PET) is expanding rapidly in most European countries. It is likely therefore that patients receiving the tracer fluorine-18 fluorodeoxyglucose (18FDG) will be discharged to come into contact with family members, members of the public and ward staff. There are few direct measurements on which to base any recommendations with regard to radiation protection, and so we have measured the dose rates from patients undergoing clinical PET examinations in our centre. Seventy-five patients who underwent whole-body and brain 18FDG PET examinations were studied. Dose rates were measured at 0.1, 0.5, 1.0 and 2.0 m from the mid thorax on leaving the department. The median administered activity was 323 MBq with a 95th percentile value of 360 MBq. The median dose rates measured at the four distances were 90.0, 35.0, 14.0 and 5.0 microSv h-1 (the median dose rates per unit administered activity at 2 h post injection were 0.31, 0.11, 0.04 and 0.02 microSv h-1 MBq-1). The corresponding 95th percentile values were 174.0, 69.0, 29.0 and 7.5 microSv h-1 (0.43, 0.2, 0.08 and 0.03 microSv h-1 MBq-1). A number of social situations were modelled and an annual dose limit of 1 mSv was used to determine whether restrictive behavioural advice was required. In the case of nursing staff on wards a value of 6 mSv was regarded as the annual limit, which translates to a daily limit of approximately 24 microSv. There is no need for restrictive advice for patients travelling by public or private transport when they leave the department 2 h after the administration of 18FDG. Similarly, there is no need for restrictive advice with regard to their contact with partners, work colleagues or children of any age, although it should be stressed that children should not accompany the patient to the scanning department. The only possible area of concern is in an oncology ward, where patients may be regularly referred for PET investigations and other high activity radionuclide studies and are partially helpless. Even in this area, however, it is unlikely that a nurse would receive a daily dose of more than 24 microSv. We conclude that there is no need for restrictive advice for patients undergoing 18FDG PET studies given the current administered activities.     

Estimation of effective dose from CT examination

Tissue or organ doses related to radiological risk were determined for four different types of CT scanners with a spiral scan function. Dose measurements were performed using a Rando phantom and two types of thermoluminescent dosimeters. The effective doses recommended by the International Commission on Radiological Protection in 1990 were evaluated using the tissue or organ doses determined with the phantom measurement. The resultant effective dose per CT examination ranged from 4.6 to 10.8 mSv for chest examination and from 6.7 to 13.3 mSv for upper abdominal examination. It should be noted that the effective dose from CT examination will be increased by increasing in the frequency of CT examinations and technical development of CT scanners.     

Diagnosis and treatment of lymphomas. Retrospective quality assessment of a 10-year material

We have performed a quality assessment of staging and treatment of 64 patients with non-Hodgkin's lymphoma treated at the Department of Internal Medicine, Nordland Central Hospital from 1982 to 1991. The assessment was based on defined quality criteria. Journal records of patient history, physical examination and stage were unsatisfactory. Histological examinations, use of laboratory tests and X-ray examinations were appropriate. The choice of chemotherapy for high grade malignancy was adequate, average relative dose-intensity was low. Low utilization of radiotherapy could be explained in most cases by individual patient factors. 5-years disease-specific survival was 54% for all patients and 70% for those presenting with localized disease.     

Impact of gowning on visit length and physical examinations

We evaluated the effect of a randomized trial of gowning on length of visit and number of physical examinations performed in an outpatient clinic. Nineteen senior internal medicine trainees saw 110 patients without gowns and 113 patients with gowns. Patients without gowns were with the trainees 25.2 +/- 11.9 (mean +/- SD) minutes versus 24.2 +/- 10.3 minutes for gowned patients (p = .51). Ungowned patients were in the examination room a total of 38.5 +/- 15.9 minutes versus 42.9 +/- 17.6 minutes for gowned patients (p = .06). The number of patients that underwent physical examinations was the same (89) for gowned and ungowned groups, and the distribution of the number of examinations by patient group differed only slightly (p = .88). Gowning did not significantly decrease the length of visit or increase the number of physical examinations performed.     

Patient dose reduction by audit of grid usage in barium enemas

Patient dose reduction may be achieved by removal of the antiscatter grid during fluoroscopy when fine detail is not required, such as during the filling phase of barium enemas. A questionnaire revealed that none of 22 trainee radiologists routinely removed the grid for the filling phase of adult barium enemas. Following this, 100 consecutive barium enemas were observed, with assessment of patient radiation dose by means of a dose-area product meter. The grid was removed in only six examinations. Phantom measurements implied a possible 46% reduction in dose for the filling phase by correct grid usage. These data were presented at a local clinical audit meeting, resulting in a change in departmental policy to recommend routine removal of the grid for the filling phase of barium enemas. In a follow-up audit the grid was removed in 96 of 100 consecutive enemas, resulting in a significant 46.5% dose reduction for the filling phase (95% confidence interval 38-61%). Further re-audit has demonstrated continued good practice.     

Radiological assessment of a new bone densitometer--the Lunar EXPERT

Dual energy X-ray absorptiometry (DXA) is one of the most widely used techniques in the management of osteoporosis and other skeletal diseases. Although patient doses from DXA are generally low, it is still necessary to measure them to assess the risk of radiation injury. We report on a study to estimate the effective dose (ED) to patients and staff from a new DXA scanner--the Lunar EXPERT, and make a comparison with a similar study carried out on a Lunar DPX-L. The entrance surface doses were measured to be 895 microGy and 10.25 microGy for the EXPERT and DPX-L, respectively. The EXPERT maximum EDs were calculated to be 74.7 microSv and 44.9 microSv for the anteroposterior (AP) lumbar spine and the proximal femur, respectively. More than 50% reduction in ED could be achieved by using a smaller scanning width. The maximum EDs for the DPX-L were calculated to be 0.21 microSv and 0.15 microSv for the AP lumbar spine and the proximal femur, respectively. The scattered dose rates (ambient dose equivalent) were measured to be less than 2 and less than 1 microSv h-1 at 50 cm and 100 cm, respectively, for the DPX-L, and the equivalent values for the EXPERT were 240 and 64 microSv h-1. Although both the patient dose and scattered dose rates are quite low relative to other radiological examinations, good practice aimed at dose reduction should still be implemented. Whilst protection for the operator is not needed for the DPX-L system, it may be (depending on the size of the room) for the EXPERT system.     

The size of acoustic neuromas: CT and MRI

The growth rate of acoustic neuromas is very variable: some tumours grow rapidly, some do not grow and some even get smaller. When making treatment decisions, it may be important to have an idea of the growth rate of the individual tumour, and this is only possible when there are comparable examinations. We performed both CT and MRI on 15 patients. Two radiologists estimated the size of their acoustic neuromas. There was a significant difference between the two examiners' calculations of tumour volumes on CT and between the first examiner's CT and MRI volume calculations. No difference was found between the two MRI volume estimations or the second examiner's estimation of volumes on CT and MRI. Measurements of the maximal tumour diameter along the pyramid showed good concordance. We conclude that measurement the size of acoustic neuromas is reproducible with MRI and the measurement of the maximal tumour diameter is in practice a better parameter for comparison than calculation of real volume.     

Predictive value of clinical examination, transrectal ultrasound and magnetic resonance imaging prior to radiotherapy in carcinoma of the cervix

The objectives of this study were to compare tumour staging and volume assessment by examination under anaesthesia (EUA), transrectal ultrasound (TRU) and magnetic resonance imaging (MRI) in patients with invasive carcinoma of the cervix, and to correlate findings with long-term outcome following treatment by radiotherapy. Tumour staging was performed on 60 patients immediately before starting radiotherapy. Clinicians and radiologists performing EUA, TRU or MRI were blinded to the results of other investigations. Tumour stage and dimensions were recorded prospectively for each technique, and analysed for concordance. The relationship between pre-treatment stage, size of tumour and patient outcome after radiotherapy was assessed, using clinical status 5 years after treatment as the truth measure. EUA, TRU and MRI assigned the same tumour stage in only 30% of patients and EUA and MRI agreed tumour stage in a further 27%. In cases of disagreement, the MRI stage correlated better with outcome than the TRU or EUA stage. There was a significant difference between tumour volume obtained from measurements made on MRI and those from TRU. 62% of patients with enlarged lymph nodes on pre-treatment MRI either died, or developed tumour recurrence or metastases. The ability of MRI to assess the full extent of bulky tumours and the presence of lymph node enlargement was an advantage over both EUA and TRU in identifying patients with a poor prognosis.     

The relationship of obesity to the frequency of pelvic examinations: do physician and patient attitudes make a difference?

Obese women are at higher risk for the development of both endometrial and ovarian carcinoma. Biochemical mechanisms represent documented causal factors but the role of psycho-social attitudes has received limited attention. This study examined the difference in the frequency of pelvic screening examinations between obese and non-obese women and the effect of physician and patient attitudes toward obesity on examination frequency. A total of 291 women subjects and 1316 physician subjects participated in this study. Data reported in this paper suggest that attitudes and behaviors are negatively influenced by weight. As subjects' weight went up, negative opinions about their appearance and reluctance to obtain pelvic examinations also increased while the likelihood of having annual pelvic examinations decreased. A substantial minority (17%) and an overwhelming majority (83%) of physicians indicated they were reluctant to perform pelvic examinations on obese and reluctant patients respectively. If physicians are more reluctant to perform pelvic examinations on obese and reluctant women and obese women are more reluctant to be examined, there may be a critical delay in detecting adenocarcinomas of the female genital tract.     

Medical malpractice involving radiologic colon examinations: a review of 38 recent cases

OBJECTIVE: Our purposes were to determine the causes of malpractice claims against radiologists performing contrast examinations of the colon and to design strategies to reduce litigation and diminish patient morbidity. MATERIALS AND METHODS: Reports of malpractice claims were collected from legal journals and databases between 1985 and 1994. For this period, 38 plaintiffs raised 52 allegations of malpractice that involved radiologists performing barium or Hypaque (meglumine diatrizoate; Winthrop Pharmaceuticals, New York, NY) colon examinations. For the 38 cases, 18 plaintiffs for decedents alleged that failure to diagnose colorectal cancer by barium enema examination caused delay in treatment and the patient's death. Eighteen plaintiffs alleged that improper performance of barium (17 cases) or meglumine diatrizoate (one case) colon examinations caused perforation of the colon, resulting in significant morbidity (15 cases) or death (three cases). Miscellaneous causes for malpractice claims were recorded in two cases. RESULTS: In 18 cases of failure to diagnose colorectal cancer, the initial radiographs were interpreted as follows: normal findings in 14 cases, diverticulosis in one case, and spastic bowel in two cases; in the remaining case, colon cancer was missed because of nonopacification of the cecum. In retrospect, 17 of 18 colorectal cancers were visualized. The delay in the diagnosis of colorectal cancer ranged from 5 to 72 months. Missed colorectal cancers occurred in the cecum (two cases), transverse colon (two cases), rectosigmoid area (nine cases), or unspecified area (five cases). In 18 cases of colon perforation, the site was the cecum (one case), transverse colon (one case), extraperitoneal rectum (seven cases), rectosigmoid area (one case), colostomy stoma (two cases), or unspecified area (six cases). One patient experienced anaphylactic shock that required hospitalization. One underwent unnecessary surgery because barium enema films showing colon cancer were mislabeled with her name. CONCLUSION: On the basis of our analyses of malpractice claims, we suggest strategies to prevent medicolegal litigation. Strategies include communicating with the patient about the type and indications of the barium enema examination, performing digital rectal examinations on all patients to detect distal rectal lesions or strictures, recognizing colon perforation, and obtaining immediate surgical consultation if colon perforation occurs. The number of missed colon cancers may be reduced by reading twice or reviewing at a later time all barium enema examinations.     

Coding mammograms using the classification "probably benign finding--short interval follow-up suggested"

OBJECTIVE: Many benign breast lesions revealed by mammography show features indicating that the lesions have a high, but not complete, likelihood of being benign. The Breast Imaging Reporting and Data System (BI-RADS) allows radiologists to classify these mammograms as "probably benign finding-short interval follow-up suggested" (category 3). We explored whether certain factors are associated with the use of category 3 in a national cancer detection program. MATERIALS AND METHODS: We analyzed data from the National Breast and Cervical Cancer Early Detection Program, a comprehensive nationwide program that provides cancer screening for low-income and medically underserved women. The study population included all women at least 40 years old who had undergone mammography on or before September 30, 1996 (n = 372,760). RESULTS: Of the 372,760 mammograms, 7.7% were classified as category 3. The probability of receiving a category 3 classification decreased as patients' ages increased. Women who were symptomatic were nearly twice as likely as women who were asymptomatic to receive a category 3 classification, and women whose clinical breast examinations had abnormal findings were more than twice as likely as women with examinations having normal findings to receive a category 3 classification. The percentage of mammograms classified as category 3 by state or tribal organization ranged from 1.4% to 14.0%. CONCLUSION: Several patient variables, including patient symptomatology, were associated with the probability of having a mammogram classified as category 3. One of the most important determinants was where the patient underwent mammography, which suggests that variability exists among radiologists themselves in using this BI-RADS code for "probably benign" mammographic lesions.     

Doses to patients in routine X-ray examinations in Malaysia

A collaborative national survey initiated by the University of Malaya and the Ministry of Health was conducted from 1993 to 1995 to establish baseline patient dose data for seven common types (12 projections) of X-ray examinations in Malaysia. A total of 12 randomly selected public hospitals and 867 patients were included in this survey. The entrance surface doses (ESD) received by the patients were measured using thermoluminescent dosemeters (TLDs) attached to the patient's skin. Histograms are presented showing wide, positively skewed distributions of measured entrance surface doses for each examination. Mean, median, first and third quartile values of ESD and median effective dose are reported. Survey results are generally comparable with those reported in the UK, USA and by the International Atomic Energy Agency (IAEA). The results also provide information on dose level for a lower weight population (mean weight 60 kg) compared with the international reference dose values based on a 70 kg standard. The findings support the importance of the on-going national quality assurance programme to ensure doses are kept to a level consistent with optimum image quality. The data will also be useful for the formulation of national guidance levels as recommended by the IAEA. Furthermore, this study provides patient dosimetry information on healthcare level II countries.     

Radiology in the neonatal intensive care unit: dose reduction and image quality

This paper describes a prospective study of the diagnostic radiation doses received in a neonatal intensive care unit (NICU) for a representative radiological technique used at our institution for a number of years and a "low dose" technique similar to that recommended by the Commission of the European Communities (CEC). A 400 speed film-screen combination was used in both techniques. A total of 363 anteroposterior (AP) chest and abdominal films of 77 neonates were accrued. For each radiograph, the entrance skin dose (FSD), energy imparted (EI) and mean whole body dose were determined. For a neonatal AP chest, there was an 18% reduction in the mean ESD per radiograph from 20.0 muGy for the representative technique to 16.4 muGy for the low dose technique (p < 0.0005). The reduction in the mean EI per radiograph values for the two techniques from 7.9 muJ to 7.1 muJ (10%) was statistically significant at the p < 0.017 level, after compensating for the difference in mean field dimensions between the two patient cohorts. The mean whole body dose per radiograph reduction from 4.4 to 3.5 muGy (20%) was statistically significant at the p < 0.0028 level. It was determined that the ESD and EI could be fitted by an exponential function in the equivalent patient diameter, a single parameter indicative of neonate size. Absolute excess childhood cancer mortality risk per film was estimated using risk factors derived for fetal exposures. A "worst case" absolute excess mortality risk per chest radiograph was estimated to be 1.40 x 10(-7) for the conventional technique and was further reduced to 1.11 x 10(-7) for the low dose technique. A blind comparison of patient-matched film pairs for each technique was performed by three radiologists using criteria similar to those specified by the CEC. No statistically significant difference in clinical image quality was found between the two techniques.