Drug-related physician continuing medical education requirements, 2010-2020

INTRODUCTION

The crisis of drug-related harm in the United States continues to worsen. While prescription-related overdoses have fallen dramatically, they are still far above pre-2010 levels. Physicians can reduce the risk of overdose and other drug-related harms by improving opioid prescribing practices and ensuring that patients are able to easily access medications for substance use disorder treatment. Most physicians received little or no training in those subjects in medical school. It is possible that continuing medical education can improve physician knowledge of appropriate prescribing and substance use disorder treatment and patient outcomes.

METHODS

Descriptive legal review. Laws in all 50 states and the District of Columbia were searched for provisions that require all or most physicians to receive either one-time or continuing medical education regarding controlled substance prescribing, pain management, or substance use disorder treatment.

RESULTS

There has been a rapid increase in the number of states with relevant requirements, from three states at the end of 2010 to 42 at the end of 2020. The frequency and duration of required education varied substantially across states. In all states, the number of hours required in relevant topics is a small fraction of overall required continuing education, an average of 1 h per year. Despite recent shifts in the substances driving overdose, most requirements remain focused on opioids.

CONCLUSION

While most states have now adopted continuing education requirements regarding controlled substance prescribing, pain management, or substance use disorder treatment, these requirements comprise a small component of the required post-training education requirements. Research is needed to determine whether this training translates into reductions in drug-related harm.

Legal Authority for Emergency Medical Services to Increase Access to Buprenorphine Treatment for Opioid Use Disorder

Treatment with buprenorphine significantly reduces both all-cause and overdose mortality among individuals with opioid use disorder. Offering buprenorphine treatment to individuals who experience a nonfatal opioid overdose represents an opportunity to reduce opioid overdose fatalities. Although some emergency departments (EDs) initiate buprenorphine treatment, many individuals who experience an overdose either refuse transport to the ED or are transported to an ED that does not offer buprenorphine. Emergency medical services (EMS) professionals can help address this treatment gap. In this Concepts article, we describe the federal legal landscape that governs the ability of EMS professionals to administer buprenorphine treatment, and discuss state and local regulatory considerations relevant to this promising and emerging practice.

Paraphernalia Laws, Criminalizing Possession and Distribution of Items Used to Consume Illicit Drugs, and Injection-Related Harm

The United States remains in the grip of an unprecedented epidemic of drug-related harm. Infections of HIV, hepatitis C, and endocarditis related to lack of access to new syringes and subsequent syringe sharing among people who inject drugs have increased alongside a surge in opioid overdose deaths.Overwhelming evidence shows that using a new syringe with every injection prevents injection-related blood-borne disease transmission. Additionally, there is promising research suggesting that the distribution of fentanyl test strips to people who inject drugs changes individuals' injection decisions, which enables safer drug use and reduces the risk of fatal overdose. However, laws prohibiting the possession of syringes and fentanyl test strips persist in nearly every state.The full and immediate repeal of state paraphernalia laws is both warranted and needed to reduce opioid overdose death and related harms. Such repeal would improve the health of people who inject drugs and those with whom they interact, reducing the spread of blood-borne disease and fatal overdose associated with infiltration of illicitly manufactured fentanyl into the illicit drug supply. It would also free up scarce public resources that could be redirected toward evidence-based approaches to reducing drug-related harm.

Kinin Activation as a Predictive Assay for Adverse Reactions to Radiographic Contrast Medium

The rate of conversion in vitro, of prekallikrein to kallikrein has been measured in 74 reactors to contrast medium and 70 controls. The conversion rate is significantly more rapid in reactors than controls. There was no difference in C1-esterase inhibitor and factor XII levels between reactors and controls. This retrospective investigation suggests that prekallikrein/kallikrein conversion rate may form the basis of a test for differentiating between reactors and non-reactors.

Bronchoscopic lung volume reduction with endobronchial valves for patients with heterogeneous emphysema and intact interlobar fissures (the BeLieVeR-HIFi trial): study design and rationale

Although lung volume reduction surgery improves survival in selected patients with emphysema, there has been ongoing interest in developing and evaluating bronchoscopic approaches to try to reduce lung volumes with less morbidity and mortality. The placement of endobronchial valves is one such technique, and although some patients have had a significant improvement, responses have been inconsistent because collateral ventilation prevents lobar atelectasis. We describe the protocol of a trial (ISRCTN04761234) aimed to show that a responder phenotype, patients with heterogeneous emphysema and intact interlobar fissures on CT scanning, can be identified prospectively, leading to a consistent benefit in clinical practice.

Airway hypersensitivity induced byAscaris suumextract in New Zealand Romney sheep

Sheep from local farms with and without previous exposure to pigs were tested for their skin and airway responses to a commercial Ascaris suum antigen. There was an immediate reaction to intradermal injection of the antigen in 90% of 101 sheep. A bronchial provocation test by aerosol of the same antigen was undertaken on 43 of the sheep with a positive skin reaction. About 70% of sheep showed an immediate airway response to the antigen as an aerosol, reflected as a significant increase in airway resistance and/or decrease of dynamic lung compliance. The mean peak airway resistance and mean lowest dynamic lung compliance were 165% above and 61% below their baselines, respectively. No significant changes were recorded when the same animals were given an aerosol of phosphate buffered saline. Similarly, no correlation was found between the degree of skin reaction and the magnitude of bronchoconstriction (p>0.05). The sheep with previous exposure to pigs showed no significant differences in airway responses to antigen challenge, although they showed significantly greater skin reactions than those without exposure to pigs. These results indicate that the majority of Romney sheep in the Manawatu have a natural skin and airway sensitivity to A. suum antigen and may therefore be used as an animal model to study human airway hypersensitivity. The origin of this sensitivity has yet to be determined.

Capsaicin cough sensitivity in bronchiectasis

BACKGROUND

Bronchiectasis is a suppurative airway disease characterised by persistent cough and sputum production associated with bronchial dilatation. A study was undertaken to determine whether cough sensitivity is increased in bronchiectatic patients.

METHODS

Twenty two patients with bronchiectasis and 20 healthy non-smoking controls matched for age and sex were recruited into the study. Quality of life (Leicester Cough Questionnaire score), total cough symptom score, and extent of bronchiectasis on HRCT scans were recorded. Cough sensitivity was assessed using incremental inhalation of capsaicin concentrations; the concentration at which 5 or more coughs occurred (C5) was recorded.

RESULTS

Patients with bronchiectasis had increased sensitivity to capsaicin compared with controls (mean (SE) log10 C5 1.22 (0.20) v 1.89 (0.21); p<0.03). Capsaicin sensitivity correlated positively with the Leicester Cough Questionnaire score (r = 0.64; p = 0.005) and inversely with the total cough symptom score (r = -0.58; p = 0.004), but not with the extent of the disease. It also correlated with forced expiratory volume in 1 second (FEV1) in litres (r = 0.58; p = 0.005) but not with FEV1 % predicted. Capsaicin sensitivity was not related to the presence of infected sputum or to corticosteroid or bronchodilator use.

CONCLUSIONS

: Patients with bronchiectasis have a sensitive cough reflex which reflects the severity of cough symptoms. A measure of cough severity could be part of health assessment for patients with bronchiectasis.

Peripheral airways obstruction on high-resolution computed tomography in chronic severe asthma

Long-standing chronic severe asthma may be associated with structural changes of both proximal and distal airways. To assess these changes, high-resolution computed tomography (CT) using an Imatron Ultrafast CT scanner with 3 mm thick sections at 10 min intervals was performed at full inspiration. A limited set of CT sections was also obtained on full expiration. Twenty-four chronic severe asthmatic patients (age, 47.0 +/- 2.4 years; FEV1, 56.5% +/- 4.1% of predicted) were studied. The scans were assessed independently by two radiologists. While concomitant dilatation and thickening of intrapulmonary airways were observed in 12 patients, air trapping as assessed by areas of increased lucency on expiratory scans was noted in 20. The mean expiratory-to-inspiratory cross-sectional area (Exp/Ins) was 75.9% +/- 2.0%, compared with 44.6% +/- 1.0% in historical non-asthmatic subjects. FEV1 (% predicted) correlated with Exp/Ins and with CT features of air trapping (both rs = 0.60; P < 0.001) but not with airway dilatation or thickening. Our data indicate the presence of peripheral airways obstruction in chronic severe asthma, which may be one of the underlying reasons for increased severity of asthma.

Non-breath-hold lung magnetic resonance imaging with real-time navigation

Magnetic resonance imaging (MRI) with navigating techniques based on consecutive breath-holds demand a level of respiratory control that is often beyond the capability of patients with lung disease. The objectives of this investigation were to develop and evaluate a navigating technique for lung MRI that does not rely on patient cooperation. Navigating techniques were implemented at 0.5 T using conventional imaging techniques of short echo-time and imaging during normal breathing in the diastolic phase of the cardiac cycle. A column of spins, orthogonal to the diaphragm, was excited both immediately before and after the imaging segment. These signals were processed in real time to provide the position of the lung-diaphragm interface. An imaging segment was considered correctly acquired only when the interface position was within the acceptance window both before and after the acquisition of the segment. A distribution of lung-diaphragm interface positions obtained during normal respiration was employed to define the acceptance window. In the case of multislice techniques, the position of the lung-diaphragm interface immediately before the imaging segment was also employed to decide which phase-encoding step to acquire next, therefore reducing the apparent frequency of the respiratory motion. A distribution of interface positions, updated in real time, served as a reference for the allocation of phase-encoding steps according to diaphragm position. The lung images obtained represent a significant advance in image quality, improving further the ability of MR to detect and monitor pulmonary disease. Motion artifacts were reduced, and images reliably demonstrated smaller vessels, which are not normally visible without navigation.

Accuracy of CT in predicting the cause of bronchiectasis

There are many reports that state that the distribution and pattern of bronchiectasis may be sufficiently characteristic for a specific cause to be suggested. The aim of this study was to determine whether experienced chest radiologists could confidently and accurately diagnose various aetiologies of bronchiectasis from the computed tomography (CT) pattern of disease alone. CT scans of 108 patients with bronchiectasis of various causes (67 with idiopathic bronchiectasis, 10 with allergic bronchopulmonary aspergillosis, 12 with syndromes of impaired mucociliary clearance, 12 with hypogammaglobulinaemia and seven with adult cystic fibrosis) were assessed by three chest radiologists without knowledge of clinical data. Each observer listed the three most likely diagnoses in order of probability. In addition, a level of confidence on a 3-point scale was assigned to the first choice diagnosis. A correct first-choice diagnosis was made in 45% of readings. A high confidence level was given in only 9% of the first choice readings. Of these, a correct diagnosis was reached in 35%. There was poor interobserver agreement (mean kappa = 0.20). In conclusion, we found that the causes of bronchiectasis cannot be reliably diagnosed on the basis of CT appearances alone.

CT findings in bronchiectasis: limited value in distinguishing between idiopathic and specific types

OBJECTIVE

The purpose of this study was to determine whether the pattern and distribution of bronchiectasis shown on CT scans can be used to discriminate between idiopathic cases and those with an identifiable cause.

MATERIALS AND METHODS

The CT scans of 168 patients with chronic purulent sputum production and who were suspected of having bronchiectasis were analyzed (117 patients with idiopathic bronchiectasis, 15 with allergic bronchopulmonary aspergillosis, 15 with hypogammaglobulinemia, 15 with impaired mucociliary clearance, and seven with cystic fibrosis diagnosed in adult life). The scans were analyzed in random order by two observers. The extent, site, type, and lobar distribution of bronchiectasis and the severity of bronchial dilatation and bronchial wall thickening were scored. The frequency of these features in the known-cause groups was compared with that in the idiopathic group to identify any significant differences.

RESULTS

Compared with idiopathic bronchiectasis, no significant lobar predominance was seen in any of the known-cause groups, apart from a higher frequency of lower lobe involvement in the patients with syndromes of impaired mucociliary clearance (p < .02). The bronchiectasis of allergic bronchopulmonary aspergillosis and adult cystic fibrosis was more often widespread (five or six lobes involved (p < .001 and p < .01, respectively) than idiopathic bronchiectasis. Central bronchiectasis was more common in allergic bronchopulmonary aspergillosis (p < .005), although the sensitivity when this was used as a diagnostic feature was only 37%. In all groups, cylindrical bronchiectasis was the most common type, with varicose and cystic bronchiectasis occurring more frequently in allergic bronchopulmonary aspergillosis (p < .01). On multiple regression analysis, allergic bronchopulmonary aspergillosis and adult cystic fibrosis showed more extensive disease than idiopathic bronchiectasis (p < .0005 and p < .001, respectively), independent of other CT features. In hypogammaglobulinemia, dilatation of the bronchial lumen was less than in idiopathic bronchiectasis (p < .02) independent of disease extent and bronchial wall thickness.

CONCLUSION

Although differences in distribution and morphology of bronchiectasis may be seen on CT scans in groups of patients with bronchiectasis of different causes, CT findings applied to individual patients are of limited value in discriminating between idiopathic bronchiectasis and bronchiectasis of various known causes.

Magnetic resonance scanning in cystic fibrosis: comparison with computed tomography

Comparison has been made between two different spin-echo sequence MR scans and CT scans of the lungs in 17 patients with cystic fibrosis. Scans were assessed for bronchial dilation, bronchial wall thickening and mucus plugging. The resolution of MR does not, at present, compare with CT. TE7 ms matched with CT for demonstrating the extent of bronchiectasis whereas TE30 ms scans were inferior to CT. Stronger background lung signal and less artefact was seen on TE7 ms scans compared with TE30 ms scans. MR is a developing technology that does not involve ionizing radiation which, with further refinement, may prove to be useful in imaging lung pathology in cystic fibrosis.

Low tissue gastrin content in the ovine distal duodenum is associated with increased percentage of G34

1. In adult sheep and in lambs, over 95% of gastrin in the abomasal antrum was G17 with small amounts of G34 and lesser amounts of Component I. 2. Low gastrin concentration in the proximal duodenum was associated with a reduced percentage of G17. 3. The proportion of G34 increased progressively down the duodenum from a mean of 7% proximally to 47% in the most distal segment, and correlated negatively in any segment with the gastrin content. 4. In both the antrum and proximal duodenum, 60-70% of the G17 was in the sulphated form. 5. The gastroepiploic venous serum contained less G17 and more G34 than the tissues and up to 19% G14.

Role of right heart receptors in the control of renin, vasopressin, and cortisol secretion in dogs

We have reported that increased left heart pressure inhibits increases in plasma renin activity (PRA), arginine vasopressin (AVP), and cortisol during arterial hypotension. The goal of this study was to determine whether increases in right heart pressure also inhibited hormonal responses to hypotension. Seven dogs were chronically instrumented with inflatable cuffs around the ascending aorta (AA), the pulmonary artery (PA), and the thoracic inferior vena cava (IVC), as well as with catheters in both atria, the abdominal aorta, and vena cava. The IVC, the PA, and the AA cuffs were inflated on different days to cause step reductions in mean arterial pressure (MAP) of 5, 10, 20, and 30% below control MAP. Graded constriction of the AA caused large increases in left atrial pressure and plasma atrial natriuretic peptide (ANP), but had no effect on plasma AVP or cortisol and caused only a small increase in PRA at the maximal reduction of MAP. Constriction of the IVC reduced both atrial pressures and plasma ANP, but stimulated increases in PRA, AVP, and cortisol. Constriction of the PA increased right atrial pressure and plasma ANP and caused increases in plasma AVP and cortisol that were similar to responses during IVC constriction, but the PRA response was only half (P < 0.05). These results indicate that increasing pressure on the right side of the heart can attenuate the PRA response to hypotension, and suggest that the inhibition is mediated by the rise in plasma ANP.

Advanced multiple beam equalization radiography (AMBER) in the detection of diffuse lung disease

To evaluate the effects of scanning equalization radiography (SER) on the detection of diffuse lung disease a clinical comparison between an Advanced Multiple Beam Equalization Radiography (AMBER) unit and conventional chest radiography was performed. Even though the overall detection of focal pulmonary lesions with the AMBER unit has been shown to be significantly higher than with conventional radiography because of the improved demonstration of the costophrenic and retrocardiac regions, the utility of AMBER in the demonstration of diffuse lung disease has not been established. Twenty-one patients with diffuse lung disease (fibrosing alveolitis or sarcoidosis) and six patients with no pulmonary disease had high kVp frontal and lateral chest radiographs on both an AMBER unit and a conventional chest stand. The pooled results of five observers using Receiver Operating Characteristic (ROC) analysis indicate that there is a slight improvement but no statistically significant difference in observer performance between AMBER (Area under the ROC curve AZ = 0.934) and conventional radiography (AZ = 0.868) in the task of detecting diffuse lung disease.

Abnormal regional distribution of ventilation in middle-aged smokers: comparison of changes in 81Krm ventilation scans and computed tomography of the lung

In 1980 we found that abnormalities in regional distribution of ventilation, as assessed by 81Krm lung scans, were common in middle-aged smokers with normal chest radiographs and mild impairment of overall lung function. In 1984 we repeated 81Krm scans in 16 continuing smokers then aged 50-64 years and with mean forced expiratory volume in one second 93% (20 SD) of predicted values who had previous 81Krm scans performed in 1980. To assess the role of disease of the peripheral airspaces in causing abnormal regional ventilation, we also obtained computed tomograms (CT) of the lungs and measured carbon monoxide transfer of the lungs in these men. Krypton scans in seven men who had normal or minor focal defects of ventilation in 1980 were unchanged in 1984. Scans in seven of the nine men who had abnormal scans in 1980 remained abnormal in 1984 but there was no overall deterioration in the abnormality of ventilation in these men; in men with similar grading in 1980 and 1984 some of the peripheral defects present in 1980 had resolved and some new abnormal areas had appeared. Minor localised abnormalities of CT scans, as assessed visually, were present in eight of the 16 men and were associated with lower values of carbon monoxide transfer coefficient (mean 78% vs 98% predicted in men with normal scans, P less than 0.01) and lung density (mean -894 vs -869 HU in men with normal scans, P less than 0.054) suggesting the CT changes were due to alveolar destruction. Abnormality of the krypton scan was not significantly associated with abnormality of the CT scan or with a reduction in carbon monoxide transfer. The results of the krypton lung scans confirm that non-uniformity of regional ventilation is often present in asymptomatic middle-aged smokers and suggest that this non-uniformity is in part due to temporary occlusion of airways. Abnormality in regional ventilation was not associated with the anatomical changes shown by the CT scan, suggesting that airway narrowing was more important than alveolar destruction in causing regional abnormalities of ventilation in these men.

Computed tomography of folded lung

Computed tomography (CT) scans of 22 examples of folded lung in nine patients were reviewed. The most important CT criteria of folded lung are the presence of vessels and bronchi running in a smooth curvilinear fashion towards a peripheral mass with an ill defined central edge associated with pleural thickening. These features were seen in all 22 examples. The lesions are frequently multiple (eight out of nine patients). When these features are present the diagnosis can be made without recourse to biopsy or thoracotomy. Enhancement with intravenous contrast medium is unnecessary and does not provide any extra useful information. Various other previously described criteria such as air bronchograms are not necessary for the diagnosis.

Computed tomography appearances of pulmonary alveolar proteinosis

The computed tomography appearances of six patients with pulmonary alveolar proteinosis are reported. In all patients the appearances are similar and are unlike pulmonary opacities in any other disease; in one patient they suggested the diagnosis. The CT appearances correlate well with histology and demonstrate septal thickening within lung involved by the disease.

Ultrasound, CT, and MRI comparison in primary and secondary tumors of the liver

Thirty-five patients with surgically removed or percutaneous biopsy-proven tumors were examined by ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI). This retrospective study describes the appearance of the primary tumors and metastases and compares the sensitivity and specificity of the 3 imaging methods. Ultrasound, CT, and MRI examinations as well as clinical, operative, and/or histologic data were available for all 35 patients. Paramagnetic contrast agent gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA) was used in 23 patients and a short TI inversion recovery MRI sequence was used in 23 patients, in addition to various spin echo MRI sequences. Thirteen patients were examined using both Gd-DTPA and the short TI inversion recovery sequence. Our comparative study--based on the following criteria: detection, size, location of the tumor, and portal vein involvement and bile duct dilatation--demonstrated an advantage of MRI over ultrasound in 16 of 35 cases, equal results in 17 of 35 cases and a disadvantage of MRI compared to ultrasound in 2 of 35 cases. With the identical criteria, MRI proved to be more informative than CT in 10 of 35 cases, equal in 21 of 35 cases, and less informative in 4 of 35 cases.

Long term follow-up of patients with Cushing's disease treated by interstitial irradiation

The first 86 patients with Cushing's disease treated with interstitial irradiation (by needle implantation) as the sole therapy were reviewed. In the 82 patients who were reassessed 1 yr after treatment 63 (77%) achieved remission. This study comprises the outcome and complications in the 54 patients who had a remission and whom we were able to follow. The follow-up period ranged from 3-26 yr (mean, 10.5) from the time of remission. No instance of clinical or radiological relapse has occurred. Of these 54 patients, yttrium-90 alone was used in 32, of whom 12 (37%) required corticosteroid or T4 replacement therapy in a mean time of 3.5 months; in 7 of these 12 we elected to give an ablative dose. Gold-198 alone was used in 15 patients, of whom 7 (47%) developed hypopituitarism in a mean time of 76 months. Both isotopes were used in 7 patients. A diurnal serum cortisol rhythm was found in 28 of the 31 patients who were not receiving corticosteroid therapy. In 5 of the 7 patients with an initially abnormal pituitary fossa, serial radiological studies revealed remodelling in 3. There have been no complications in the last 17 years. Pituitary implantation with yttrium-90 is an effective alternative to transsphenoidal hypophysectomy, with a high remission rate, no recurrence (as yet), no operative complications, and avoidance of hormone replacement in the majority.

The afferent innervation of the face of sheep and goats

The sensory innervation of the maxillary hairy skin and buccal mucous membrane was studied in anaesthetised sheep and goats. An electrophysiological technique isolated 47 single afferent units from the infraorbital nerve under chloralose or halothane anaesthesia. Mechanoreceptors of hairy skin were located in association with the following features: sinus hairs (n = 9); central primary hairs (n = 18); clear marginal hairs (n = 7) and skin-not-hair (n = 3). Units responded to hair tip displacement of 35 to 50 microm. Afferent units were also located in the mucous membrane of the cheek either associated with conical papillae (n = 8), or unassociated with papillae (n = 1). Receptor responses associated with hairs were classified as rapidly adapting (n = 18) and slowly adapting (n = 18) mechanoreceptor responses during sustained hair deflection. Seven mechanoreceptors of hairy skin and mucous membrane were excited by a fall in surface temperature. Two specific cold thermoreceptors were found: one in hairy skin and one in the mucous membrane. These units had phasic discharges during abrupt thermal depression and static discharges at constant surface temperatures. All afferent units had myelinated axons as indicated by their conduction velocities (range 20 to 57 m sec-1, mean 34 m sec-1). It is concluded that the mechanoreceptors identified had similarities with those of other mammalian species and some distinct differences. An interesting feature of mechanoreceptors in the buccal mucosa was their cold sensitivity. They therefore shared characteristics with mechanoreceptors in the penile mucosa of the ram and tongue of the sheep.

Neurophysiologic maps of cutaneous innervation of the external genitalia of the ram

The area of skin innervated by the afferent fibers in a peripheral nerve is called the cutaneous area (CA) of that nerve. Mapping of those areas that were responsive to movement of wool/hairs in the genital region of 18 anesthetized rams, combined with subsequent identification of spinal nerves and dissection of the pudendal nerve plexus, indicated considerable differences in the extent of the CA and the origins of cutaneous branches from the pudendal plexus. The CA of the proximal and distal cutaneous branches of the pudendal nerve (or plexus) overlapped craniocaudally by approximately one-half, and the latter included most of the skin of the ipsilateral half of the scrotum. The CA of the deep perineal and caudal rectal nerves lay immediately adjacent to the anus. The CA of the scrotal branches of the pudendal nerve were restricted primarily to the scrotum. Fascicles in the dorsal nerve of the penis irregularly supplied CA along the length of the prepuce and consistently supplied the cranial free end of the prepuce. The CA of the ventral cutaneous branches of the caudal thoracic spinal nerves, the first 2 or 3 lumbar spinal nerves, and the genitofemoral nerve extended to the midline of the prepuce. Overlapping of CA was extensive, especially on the prepuce.

Effective long-term treatment of acromegaly with a long-acting somatostatin analogue (SMS 201-995)

Nine acromegalic patients, six previously untreated, were studied before and after 3-15 months of treatment with a long-acting somatostatin analogue (SMS 201-995; 100 micrograms injected s.c. three times daily). During treatment, the mean (+/- SEM) 24-h GH concentration fell from 82 +/- 22 mIU/l to 33 +/- 7 mIU/l (P less than 0.001), and eight of the 9 patients showed a reduction of at least 50% in GH levels in the fasting state and/or during a glucose tolerance test. There was a significant 30% fall in serum concentrations of insulin-like growth factor (IGF-1) with SMS. All patients showed rapid clinical improvement, with diminished sweating and headaches, and reduction in skinfold thickness, hand volumes and finger size. Computer tomographic scanning of the pituitary in eight patients showed no change in the size of the pituitary tumour during treatment. The only side-effects of SMS noted were transient abdominal discomfort and loose stools in two patients on initiating therapy. Although fasting plasma glucose concentration did not change during treatment (5.4 +/- 0.3 vs 5.5 +/- 0.3 mmol/l), mean 24-h plasma glucose concentration was higher with SMS (6.6 +/- 0.5 mmol/l vs 6.0 +/- 0.4 mmol/l; P less than 0.02). Mean 24-h plasma insulin concentration fell from 87 +/- 11 mIU/l before treatment to 39 +/- 6 mIU/l during treatment (P less than 0.005). No change in other anterior pituitary hormones was observed. SMS appears to be a safe, rapidly effective, long-term treatment for certain patients with acromegaly.

The radiology of fibrolamellar hepatoma

Seven patients with fibrolamellar hepatoma were examined with computed tomography (CT), ultrasonography and angiography. On CT the tumours were large, of low attenuation, had a well-defined edge and some contained areas of calcification or necrosis. Ultrasonography revealed well-defined masses of mixed echogenicity, occasionally involving the portal vein. In one patient there was dilatation of the intrahepatic biliary tree. Arteriography showed vascular tumours with involvement of the portal vein in five cases and compression of the inferior vena cava in five cases. CT and ultrasonography are the most useful radiological investigations for suggesting the diagnosis of fibrolamellar hepatoma which should be considered in the case of any large solitary well-defined hepatic tumour in the noncirrhotic liver of a young person.

Gadolinium-DTPA in the assessment of liver tumours by magnetic resonance imaging

The effect of gadolinium-DTPA (Gd-DTPA, Schering AG) as a magnetic resonance imaging (MRI) contrast agent was studied in 15 patients with liver tumours. A dose of 0.1 mmol/kg was used. An analysis of the time-course of enhancement, a comparison of four different pulse sequences, and a dose-comparison study were carried out with monitoring of haematological and biochemical parameters before and after injection of Gd-DTPA. Maximum enhancement, that is, increase in signal intensity, was noted on IR1400/400/13 between 10 and 20 min after injection while on SE580/40 and SE580/80 maximum enhancement was noted 30 min after injection. In some cases enhancement was noted up to 120 minutes after injection. SR1000/13f sequences showed very little enhancement. On comparison with contrast-enhanced X-ray computed tomography (CT), enhancement was greater on MRI in seven cases, equal in six and less in two, as assessed subjectively. Additional lesions were shown in one case using Gd-DTPA compared to precontrast enhanced MRI scans. However, no additional lesions were seen on contrast-enhanced MRI scans compared to contrast-enhanced CT scans. Gd-DTPA is capable of enhancing liver tumours on MRI and may have a place in the assessment of the operability of such lesions.

Bile duct obstruction: radiologic evaluation of level, cause, and tumor resectability

In a prospective study of 65 patients with bile duct obstruction, various radiologic modalities were compared for their capability to demonstrate the level and cause of obstruction and to indicate accurately tumor resectability. Ultrasound (US) was performed in 65 patients, computed tomography (CT) in 51, direct cholangiography (DC) in 57, and angiography in 35. The level of obstruction was correctly indicated by US in 95% of patients and by CT in 90%, and the cause was correctly indicated by US in 88%, by CT in 63%, and by DC in 89%. In predicting tumor resectability, US was correct in 71% of patients, compared with 42% for CT, 58% for DC, and 25% for angiography. US therefore appears to be the single most useful modality in the evaluation bile duct obstruction.

Reactions to radiographic contrast media: an attempt to detect specific anti-contrast medium antibodies in the sera of reactor patients

A radioimmunoassay was used in an attempt to detect specific anti-contrast medium antibodies in the sera of a group of 68 patients who reacted to radiographic contrast media and a group of 30 age-, sex- and disease-matched control patients who did not react. No evidence of specific antibodies of the IgG or IgE classes was demonstrated in these two groups. The results suggest the lack of an antibody-mediated aetiology for reactions to radiographic contrast media.

Remission of symptoms during long term treatment of metastatic pancreatic endocrine tumours with long acting somatostatin analogue

Five patients with metastatic pancreatic endocrine tumours injected a long acting somatostatin analogue (SMS 201-995) 50 micrograms subcutaneously every 12 hours and were followed up for three to six months. Treatment aimed at controlling excess secretion of hormone by the tumours thereby bringing symptomatic relief. Four patients showed a significant reduction in tumour related hormone concentrations but in none did values return to normal. All five patients, however, noted definite symptomatic improvement and in one this was dramatic (disappearance of life threatening diarrhoea and correction of metabolic acidosis and hypokalaemia within 48 hours). Mild worsening of symptoms and increasing fasting tumour related hormone concentrations after three to six months of treatment were reversed by doubling the 12 hourly dose. The treatment was well tolerated and had no deleterious effect on fasting blood glucose concentrations. This somatostatin analogue seems a promising non-invasive treatment for metastatic pancreatic endocrine tumours.

Paramagnetic contrast media for magnetic resonance imaging of the mediastinum and lungs

The use of paramagnetic contrast agents in magnetic resonance imaging (MRI) of the lungs and mediastinum has been the subject of preliminary investigation. Gadolinium-DTPA (Gd3+-DTPA) is a suitable intravenous paramagnetic contrast agent for imaging cerebral tumors and liver tumors. Its use in the thorax is more speculative, but early animal experimental data suggest that contrast-enhanced MRI may have a place in the assessment of pulmonary edema and lung parenchymal damage.

Pneumocystis carinii pneumonia in renal transplant recipients--clinical and radiographic features, diagnosis and complications of treatment

Six episodes of Pneumocystis carinii pneumonia in five renal transplant patients on low dose maintenance prednisolone are described. The infection was rare, occurring in 3 per cent of the recipients transplanted between 1978 and 1984. Diagnosis and treatment were not straightforward. Fever was the earliest evidence of illness, and in three episodes the chest radiograph was normal at presentation. At diagnosis, two to 16 days later, all had pulmonary infiltrates and severe hypoxia. Diagnosis was confirmed by cytological examination of bronchial lavage (two), transbronchial biopsy (one), open lung biopsy (one), and for two episodes clinically, from the rapid and complete resolution of fever, pulmonary infiltrates and hypoxia following a therapeutic trial of high dose cotrimoxazole. Pneumocystis antibody titres were low during the illness and in convalescence and did not contribute to diagnosis. Three patients had serological evidence of recent cytomegalovirus infection. All episodes responded to treatment with high dose cotrimoxazole. All the patients survived the illness but one died a year after recovery. The major complications of treatment were thrombocytopenia (three cases) and neutropenia (two cases) which did not respond to folinic acid.

Contrast agents in magnetic resonance imaging

With the advent of magnetic resonance imaging (MRI) it has become apparent that paramagnetic contrast agents may have a place in clinical practice. The mechanism of action, development, techniques of use and initial animal and clinical results are reviewed. Gadolinium diethylene triamine penta acetic acid (Gd3+-DTPA) has proved an effective paramagnetic contrast agent in experimental animals and clinical trials with this agent commenced in November-December 1983. Gd3+-DTPA will cross a damaged blood-brain barrier, is excreted mainly by glomerular filtration and is distributed mainly in the extracellular space. No short-term toxicity has been detected. Long-term toxicity is, as yet, unknown. Optimum dose, pulse sequences and timing of imaging remain to be determined by further studies but Gd3+-DTPA shows promise as a useful addition to MRI.

Percutaneous catheter nephrostomy drainage--results of 70 procedures

Percutaneous nephrostomy (PCN) was performed 70 times in 46 patients. In the majority of cases the procedure was carried out as an emergency to relieve urinary obstruction. 20 of the patients had subsequent elective surgery, in others PCN allowed time for other forms of treatment to become effective. The technique carries a low mortality and morbidity, can be performed using either fluoroscopic or ultrasound imaging and should be available in all radiology departments.

Comparison of barium and diatrizoate bowel labelling agents in computed tomography

A new suspension of barium sulphate, E-Z-CAT, for use as a bowel labelling agent in computed tomography (CT) of the abdomen and pelvis, has been compared with diatrizoate (Gastrografin) in 111 patients. The E-Z-CAT labelled the duodenum more efficiently and patients preferred its taste. Both substances are satisfactory bowel-labelling agents.

Gadolinium-DTPA as a contrast agent in MR imaging--theoretical projections and practical observations

The theoretical basis for the use of paramagnetic agents to enhance proton relaxation is described. Factors of importance in the design of contrast agents are considered. Measurements of changes in T1 and T2 in vitro due to Gd3+-diethylenetriamine pentaacetic acid (DTPA) are used to predict changes in the intensity of transverse magnetisation seen with different sequences in magnetic resonance imaging. The use of Gd3+-DTPA in clinical cases is illustrated.

The role of CT in the diagnosis of primary lymphedema of the lower limb

Twelve patients with primary lymphedema of the lower limb were examined with computed tomography (CT). A characteristic "honeycomb" pattern of the subcutaneous compartment was seen in 10 of these patients. CT scans in nine other patients with swollen leg secondary to chronic venous disease or lipedema did not show this characteristic pattern. CT may be helpful in the differential diagnosis of a swollen leg, thus obviating venography or lymphangiography.

Long-term treatment of a VIPoma with somatostatin analogue resulting in remission of symptoms and possible shrinkage of metastases

A 43-yr-old-man with metastatic VIPoma in whom the conventional measures of surgery, chemotheraphy, and hepatic artery embolization ultimately failed to control his severe diarrhea, resulting from vasoactive intestinal polypeptide hypersecretion, was treated with a new long-acting somatostatin analogue, SMS 201-995, for 14 mo. SMS 201-995 not only controlled the diarrhea without side effects but appeared to have possibly induced a reduction in metastatic tumor size.

Gadolinium-DTPA as a contrast agent in MRI: initial clinical experience in 20 patients

Magnetic resonance imaging (MRI) was performed in 20 patients before and after intravenous administration of gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA) in a dose of 0.1 mmol/kg. Twelve of the patients had clinical and histologic diagnoses of cerebral tumor, six had hepatic tumors, one had hepatic cysts, and one had transitional cell carcinoma of the bladder. Contrast enhancement was seen with all tumors, but not with the hepatic cysts. The degree of enhancement was greater than that seen with computed tomography (CT) in 13 cases, equal to it in six, and less in one. Contrast enhancement was detectable as long as 18 hr after injection of Gd-DTPA in one case of cerebral tumor. The margin between cerebral tumor and peritumoral edema could be delineated with contrast-enhanced MRI to the degree possible with contrast-enhanced CT. In the liver isointense enhancement was seen with saturation-recovery (SR), inversion-recovery (IR), and spin-echo (SE) sequences although not with all three sequences simultaneously. In general IR sequences were most sensitive for display of the contrast agent, but the enhancement often decreased the difference between abnormal and normal tissue. No short-term side effects were encountered and no significant change was seen in urea, creatinine, electrolytes, liver function tests, blood coagulation, or urine testing after injection of Gd-DTPA. Although much more work will be required to evaluate this contrast agent, these initial experiences are very promising.

Computed tomography of sellar and parasellar lesions

The findings in 50 patients examined by computed tomography (CT) of the pituitary fossa are described. The appearances in 43 were judged to be abnormal, four were normal and three were 'doubtful'. Abnormal features included deviation of the pituitary stalk (seven), localised increased enhancement after intravenous injection of contrast medium (18) and extrasellar extension of tumour (11). The CT scans enabled diagnoses of pituitary microadenoma, empty sella and combinations of the two to be made. Modern CT scanners (third or fourth generation) provide detailed information enabling the optimum assessment and treatment of sellar and parasellar lesions.

The regulation of parotid and submandibular salivary secretion in sheep

During eating the parotid and submandibular salivary glands of sheep are stimulated via parasympathetic and sympathetic pathways. The response of the glands depends on the nature of the diet and the duration of a meal. In anaesthetized animals a continual activity in the parasympathetic nerve supply to the parotid gland reflects the excitatory effects of rumino-reticular (gastric) distension and contraction. This activity is reduced by high levels of rumino-reticular distension and increased osmolality of venous blood. It is argued that in conscious sheep these factors are important in determining the volume of saliva that is normally produced. Mechanoreceptors in the parotid glands of sheep are also a source of considerable afferent activity. Some of these receptors are active during naturally stimulated secretion and it is suggested they may also have a role in regulating salivary gland function.

Contrast media reactions: experimental evidence against the allergy theory

In order to clarify whether adverse reactions to radiographic contrast media may be allergic in nature, it is essential to show that contrast media can act as haptens and induce antibody formation in vivo. Experiments in Hooded Lister rats have been carried out using techniques specifically designed to produce favourable conditions for the production of antibodies. No evidence of any antibody formation was found in any of the experiments. These experiments suggest that radiographic contrast media in their native form do not act as haptens, contrary to previously published data, and it therefore seems unlikely that the majority of adverse reactions to radiographic contrast media are allergic in nature.

Iron and gadolinium chelates as contrast agents in NMR imaging: preliminary studies

Iron (Fe2+) and gadolinium (Gd3+) chelated to ethylenediaminetetraacetic acid and Gd3+ chelated to diethylenetriamine pentaacetic acid have been used as contrast agents in nuclear magnetic resonance imaging of the normal kidney and cerebral infarction in rabbits. All three agents produced observable changes with inversion-recovery images and marked changes in T1.

Visibility of the renal fascia at intravenous urography

Contrary to the accepted understanding that visibility of the perirenal fascia at urography is a rare finding and when seen is usually associated with renal pathology, a recent report has suggested that it is a fairly common, normal finding. In a retrospective study, 261 unselected intravenous urograms performed over a 3-month period were analysed. The findings indicate a low incidence of perirenal fascia visualisation and, when present, an association with renal pathology.