Laparoscopic management of insulinomas

BACKGROUND

Conventional surgical management of insulinomas involves an open technique. The laparoscopic approach has advantages in terms of improved postoperative pain and recovery time. This retrospective study evaluated the laparoscopic management of pancreatic insulinomas.

METHODS

Between December 2000 and March 2007, 23 patients were referred for consideration of laparoscopic insulinoma resection. Two patients were not deemed appropriate for the laparoscopic approach and were managed with open surgery. All surgery was performed by one experienced pancreatic surgeon. Laparoscopic intraoperative ultrasonography was not available for the first six procedures, but was used thereafter.

RESULTS

Twenty-one patients (five men and 16 women, median age 46 (range 22-70) years) had a successful resection. All had single tumours, five in the head, nine in the body and seven in the tail of the pancreas. One conversion to open operation was performed in a patient with an insulinoma in the head of the pancreas who had dense adhesions resulting from pancreatitis. Three patients developed a postoperative pancreatic fistula. There has been no recurrence of symptoms in any patient.

CONCLUSION

Laparoscopic management of insulinomas is feasible and safe. Laparoscopic intraoperative ultrasonography is a promising adjunct to the procedure, even after accurate preoperative localization.

Estimates of maternal risks of pregnancy for women with hereditary haemorrhagic telangiectasia (Osler-Weber-Rendu syndrome): suggested approach for obstetric services

OBJECTIVES

Hereditary haemorrhagic telangiectasia (HHT) affects 1 in 5-8000 individuals. Pregnancy outcomes are rarely reported. The major reason is that most women do not have their HHT diagnosed prior to pregnancy. Using a large well-characterised series, we studied all pregnancies known to have occurred in HHT-affected women, whether or not their diagnosis was known at the time of pregnancy. Our aim was to estimate rates and types of major complications of HHT in pregnancy, to guide management decisions.

DESIGN

Cohort study, with prospective, retrospective and familial components.

SETTING/POPULATION

Tertiary referral centre population.

METHODS

All 262 pregnancies in the 111 women with HHT and pulmonary arteriovenous malformations (PAVMs) reviewed between 1999 and 2005 were studied. Eighty-two women (74%) did not have a diagnosis of HHT/PAVM at the time of pregnancy. 222 pregnancies in their 86 HHT-affected relatives were also studied.

MAIN OUTCOME MEASURES

PAVM bleed, stroke and maternal death.

RESULTS

Thirteen women experienced life-threatening events during pregnancy: 1.0% (95% CI 0.1-1.9) of pregnancies resulted in a major PAVM bleed; 1.2% (0.3-2.2%) in stroke (not all were HHT related); and 1.0% (0.13-1.9%) in maternal death. All deaths occurred in women previously considered well. In women experiencing a life-threatening event, prior awareness of HHT or PAVM diagnosis was associated with improved survival (P = 0.041, Fisher's exact test).

CONCLUSIONS

Most HHT pregnancies proceed normally. Rare major complications, and improved survival outcome following prior recognition, means that pregnancy in a woman with HHT should be considered high risk. Recommendations for pregnancy management are provided.

Embolisation of pulmonary arteriovenous malformations: no consistent effect on pulmonary artery pressure

Increasing evidence supports the use of embolisation to treat pulmonary arteriovenous malformations (AVMs). Most pulmonary AVM patients have hereditary haemorrhagic telangiectasia (HHT), a condition that may be associated with pulmonary hypertension. The current authors tested whether pulmonary AVM embolisation increases pulmonary artery pressure (P(pa)) in patients without baseline severe pulmonary hypertension. P(pa) was measured at the time of pulmonary AVM embolisation in 143 individuals, 131 (92%) of whom had underlying HHT. Angiography/embolisation was not performed in four individuals with severe pulmonary hypertension, whose systemic arterial oxygen saturation exceeded levels usually associated with dyspnoea in pulmonary AVM patients. In 143 patients undergoing pulmonary AVM embolisation, P(pa) was significantly correlated with age, with the most significant increase occurring in the upper quartile (aged >58 yrs). In 43 patients with repeated measurements, there was no significant increase in P(pa) as a result of embolisation. In half, embolisation led to a fall in P(pa). The maximum rise in mean P(pa) was 8 mmHg: balloon test occlusion was performed in one of these individuals, and did not predict the subsequent rise in P(pa) following definitive embolisation of the pulmonary AVMs. In the present series of patients, which excluded those with severe pulmonary hypertension, pulmonary artery pressure was not increased significantly by pulmonary arteriovenous malformation embolisation.

Primary determinants of ischaemic stroke/brain abscess risks are independent of severity of pulmonary arteriovenous malformations in hereditary haemorrhagic telangiectasia

BACKGROUND

Brain abscesses and ischaemic strokes complicate pulmonary arteriovenous malformations (PAVMs). At risk individuals are poorly recognised. Stroke/abscess risk factors have not been defined.

METHODS

A cohort study of 323 consecutive individuals with PAVMs (n = 219) and/or the commonly associated condition hereditary haemorrhagic telangiectasia (HHT, n = 305) was performed. Most of the 201 individuals with PAVMs and HHT had no respiratory symptoms, and were unaware they had HHT. Anderson-Gill models assessed constant and time dependent potential predictive variables for stroke/abscess, and rate reduction by PAVM embolisation.

RESULTS

57 individuals with PAVMs and HHT experienced brain abscess or ischaemic stroke, usually prior to the diagnosis of underlying PAVMs/HHT. The primary determinants of stroke and abscess risks were unrelated to severity of PAVMs. Males had higher brain abscess rates (hazard ratio 3.61 (95% CI 1.58, 8.25), p = 0.0024); interventional histories and bacteriological isolates suggested dental sources. Once adjusted for gender, there was a marginal association between brain abscess and low oxygen saturation. For ischaemic stroke, there was no association with any marker of PAVM severity, or with conventional neurovascular risk factors. Surprisingly, low mean pulmonary artery pressure was strongly associated with ischaemic stroke (hazard ratio 0.89 (95% CI 0.83, 0.95) per mm Hg increase; p = 6.2x10(-5)). PAVM embolisation significantly reduced ischaemic stroke rate (p = 0.028); no strokes/abscesses occurred following obliteration of all angiographically visible PAVMs. The mean PAVM diagnosis-treatment interval was longer, however, when neurological risks were unrecognised.

CONCLUSIONS

Ischaemic strokes and brain abscesses occur commonly in undiagnosed HHT patients with PAVMs. Risk reduction could be improved.

Mid-trimester dilation and evacuation with laminaria does not increase the risk for severe subsequent pregnancy complications

OBJECTIVE

To evaluate subsequent pregnancy outcomes in women with a previous mid-trimester (12-24 weeks) pregnancy termination by dilation and evacuation (D&E) as compared to women without a previous D&E.

METHOD

Medical records for women who underwent a D&E between 1995 and 2003 were identified and reviewed. Women with subsequent pregnancies were compared on a 1:2 basis with women in a control group who had viable pregnancies and no previous mid-trimester DE. Outcomes of interest included preterm labor, placental abnormalities, and a composite complication outcome.

RESULTS

Of the 317 women who underwent a D&E, 85 had viable subsequent pregnancies. These women delivered slightly earlier than the 170 controls (38.9 versus 39.5 weeks, p=0.001), although there was no statistically significant difference between the two groups with regard to birth weights, spontaneous preterm delivery, abnormal placentation, and overall complication rate.

CONCLUSIONS

Mid-trimester termination by D&E does not increase the rate of clinically significant subsequent pregnancy complications.

Problem drinking: rural and urban trends in America, 1995/1997 to 2003

OBJECTIVE

Studies examining trends in problem alcohol use for U.S. adults residing in rural locations are lacking. This study examines recent trends in heavy and binge drinking in urban counties and three types of rural counties.

METHODS

Random-digit telephone survey of adults aged 18 years or older residing in states participating in the Behavioral Risk Factor Surveillance System, in the years 1995/1997 (n = 247,255), 1999/2001 (n = 362,077) and 2003 (n = 257,659). Analyses were performed in 2006.

RESULTS

Metropolitan counties experienced higher prevalence of heavy and binge drinking than rural counties in all years, and all geographic areas showed upward trends in both drinking behaviors. Trends in heavy drinking were sharper in rural counties (3.8% to 5.4% compared with 4.9% to 6.0% in metro counties). Metropolitan and rural counties overall saw similar increases in binge drinking, however, the greatest increase occurred in remote micropolitan counties (12.7% to 15.7%).

CONCLUSION

Heavy and binge drinking are problems that continue to increase in rural areas nationwide. Because of the difficulties inherent in accessing and administering substance abuse treatment in rural areas, special attention should be given to tailoring alcohol abuse interventions to the needs of rural residents.

Prevalence and trends in smoking: a national rural study

CONTEXT

Cigarette smoking is the leading preventable cause of death in the United States.

PURPOSE

To estimate the prevalence of and recent trends in smoking among adults by type of rural location and by state.

METHODS

Random-digit telephone survey of adults aged 18 years or older who participated in the Behavioral Risk Factor Surveillance System in 1994-1996 (n = 342,055) and 2000-2001 (n = 385,384). The main outcome measure was current cigarette smoking, defined as persons who smoke every day or some days, while nonsmokers were those who smoke not at all or reported never having smoked as many as 100 cigarettes.

FINDINGS

The prevalence of smoking changed little from the mid-1990s; in 2000-2001, it was 22.0% in urban areas, 24.9% in rural adjacent areas, 24.0% in large rural nonadjacent areas, and 24.9% in small rural nonadjacent areas. For rural locations combined, smoking prevalence was not below the 12% goal of Healthy People 2010 for any state, although the 12.5% prevalence in rural Utah approached this target. Prevalence was > or = 28% for rural residents of Kentucky, Ohio, and Indiana. Since the mid-1990s, the prevalence of smoking for rural respondents decreased by more than 2 percentage points in 6 states: California, Connecticut, Maryland, North Carolina, Tennessee, and Utah. However, it increased by 2 percentage points or more in 10 states: Alabama, Delaware, Georgia, Massachusetts, Michigan, Mississippi, New Hampshire, Oklahoma, South Carolina, and Texas.

CONCLUSIONS

Smoking remains a refractory public health problem. Better ways to curb smoking in rural America are needed.

Reliability of Group Health Cooperative automated pharmacy data by drug benefit status

PURPOSE

Evaluate the reliability of health plan pharmacy records in determining medication use among seniors with and without a drug benefit.

METHODS

Subjects included 3610 seniors, enrolled in Group Health Cooperative's Medicare (GHC) + Choice program during 1998-1999, receiving care in an integrated group practice (IGP), and diagnosed with one or more of four chronic conditions (hypertension, diabetes, congestive heart failure, and coronary artery disease). We compared pharmacy records to self-reported medication use for antidepressant, antihypertensive, acid suppressant, cardiac, diabetic, hormone, and lipid lowering drugs.

RESULTS

Agreement between pharmacy records and self-report was substantial to almost perfect (prevalence-adjusted and bias-adjusted kappa (PABAK) range: 0.69 for antihypertensives to 0.95 for cardiac agents) among seniors with a drug benefit. Agreement was slightly less for seniors without a drug benefit (PABAK range: 0.51 for antihypertensives to 0.92 for cardiac agents) and differences varied by drug class. Among seniors without a benefit, the prevalence of medication use was lower when based on pharmacy records than when based on self-report for all medication classes of interest.

CONCLUSIONS

While GHC may not be representative of all health plans, our study indicates that health plan pharmacy records are a reliable source of data for seniors receiving care within an IGP. However, the reliability of pharmacy records appears better among seniors with a drug benefit. Researchers should consider factors such as drug benefit status when conducting studies using pharmacy data. More studies are needed in different populations and delivery systems, as well as over varied types of drug benefits.

Pulmonary artery-to-pulmonary artery anastomoses: angiographic demonstration in patients with chronic thromboembolic pulmonary hypertension

AIM

To describe direct pulmonary artery-to-pulmonary artery anastomoses seen at pulmonary angiography in patients with chronic thromboembolic pulmonary hypertension and discuss their possible significance.

MATERIALS AND METHODS

Between 1 August 2000 and 31 July 2004 43 patients (male-to-female ratio 25:18) with a diagnosis of chronic thromboembolic pulmonary hypertension (CTEPH) underwent selective pulmonary angiography to assess the extent of disease and suitability for surgical pulmonary endarterectomy. The mean pulmonary artery pressure ranged from 27-84 mmHg (average of 51 mmHg). Selective bilateral digital subtraction pulmonary angiograms performed in all individuals were reviewed for the presence of intrapulmonary collaterals.

RESULTS

In 15 of the 43 patients (male-to-female ratio =7:8) definite (n = 12) or probable (n = 3) pulmonary artery-to-pulmonary artery anastomoses were demonstrated. Of the remaining 28 patients in whom intrapulmonary collaterals were not seen it was felt that in 16 the angiograms were of insufficient diagnostic quality (grades 4-5) to exclude their presence. Twelve patients, eight of whom had angiograms of sufficient diagnostic quality (grades 1-3), demonstrated one or more areas of luxury perfusion but intrapulmonary collaterals were not seen.

CONCLUSION

Direct pulmonary artery-to-pulmonary artery anastomoses were demonstrated in patients with chronic thromboembolic pulmonary hypertension, which to our knowledge have not been previously described. The importance of these collateral vessels is unclear but they may play a role in the maintenance of pulmonary parenchymal viability in patients with chronic pulmonary embolic disease. The rate of development of these collaterals and their prognostic significance in patients with chronic thromboembolic pulmonary hypertension are areas worthy of further study.

Trends in professional advice to lose weight among obese adults, 1994 to 2000

CONTEXT

Obesity is a fast-growing threat to public health in the U.S., but information on trends in professional advice to lose weight is limited.

OBJECTIVE

We studied whether rising obesity prevalence in the U.S. was accompanied by an increasing trend in professional advice to lose weight among obese adults.

DESIGN AND PARTICIPANTS

We used the Behavioral Risk Factor Surveillance System, a cross-sectional prevalence study, from 1994 (n = 10,705), 1996 (n = 13,800), 1998 (n = 18,816), and 2000 (n = 26,454) to examine changes in advice reported by obese adults seen for primary care.

MEASUREMENTS

Self-reported advice from a health care professional to lose weight.

RESULTS

From 1994 to 2000, the proportion of obese persons receiving advice to lose weight fell from 44.0% to 40.0%. Among obese persons not graduating from high school, advice declined from 41.4% to 31.8%; and for those with annual household incomes below 25,000 dollars, advice dropped from 44.3% to 38.1%. In contrast, the prevalence of advice among obese persons with a college degree or in the highest income group remained relatively stable and high (> 45%) over the study period.

CONCLUSIONS

Disparities in professional advice to lose weight associated with income and educational attainment increased from 1994 to 2000. There is a need for mechanisms that allow health care professionals to devote sufficient attention to weight control and to link with evidence-based weight loss interventions, especially those that target groups most at risk for obesity.

A national study of obesity prevalence and trends by type of rural county

CONTEXT

Obesity is epidemic in the United States, but information on this trend by type of rural locale is limited.

PURPOSE

To estimate the prevalence of and recent trends in obesity among US adults residing in rural locations.

METHODS

Analysis of data from the Behavioral Risk Factor Surveillance System (BRFSS) for the years 1994-1996 (n = 342,055) and 2000-2001 (n = 385,384). The main outcome measure was obesity (body mass index [BMI] > or = 30), as determined by calculating BMI from respondents' self-reported height and weight.

RESULTS

In 2000-2001, the prevalence of obesity was 23.0% (95% confidence interval [CI] 22.6%-23.4%) for rural adults and 20.5% (95% CI 20.2%-20.7%) for their urban counterparts, representing increases of 4.8% (95% CI 4.2%-5.3%) and 5.5% (95% CI 5.1%-5.9%), respectively, since 1994-1996. The highest obesity prevalence occurred in rural counties in Louisiana, Mississippi, and Texas; obesity prevalence increased for rural residents in all states but Florida over the study period. African Americans had the highest obesity prevalence of any group, up to 31.4% (95% CI 29.1%-33.6) in rural counties adjacent to urban counties. The largest difference in obesity prevalence between those with a college education compared with those without a high school diploma occurred in urban areas (18.4% [95% CI 17.9%-18.9%] vs 23.5% [95% CI 22.5%-24.5%], respectively); the smallest difference occurred in small, remote rural counties (20.3% [95% CI 18.7%-21.9%] versus 22.3% [95% CI 20.7%-24.0%], respectively).

CONCLUSIONS

The prevalence of obesity is higher in rural counties than in urban counties; obesity affects some residents of rural counties disproportionately.

Prescription Drug Coverage, Health, and Medication Acquisition Among Seniors With One or More Chronic Conditions

BACKGROUND

The unabated rise in medication costs particularly affects older persons with chronic conditions that require long-term medication use, but how prescription benefits affect medication adherence for such persons has received limited study.

OBJECTIVE

We sought to study the relationship among prescription benefit status, health, and medication acquisition in a sample of elderly HMO enrollees with 1 or more common, chronic conditions.

RESEARCH DESIGN

We implemented a cross-sectional cohort study using primary survey data collected in 2000 and administrative data from the previous 2 years.

SUBJECTS

Subjects were aged 67 years of age and older, continuously enrolled in a Medicare + Choice program for at least 2 years, and diagnosed with 1 or more of hypertension, diabetes, congestive heart failure, and coronary artery disease (n = 3073).

MEASURES

Outcomes were the mean daily number of essential therapeutic drug classes and refill adherence.

RESULTS

In multivariate models, persons without a prescription benefit acquired medications in 0.15 fewer therapeutic classes daily and experienced lower refill adherence (approximately 7 fewer days of necessary medications during the course of 2 years) than those with a prescription benefit. A significant interaction revealed that, among those without a benefit, persons in poor health acquired medications in 0.73 more therapeutic classes daily than persons in excellent health; health status did not significantly influence medication acquisition for those with a benefit.

CONCLUSIONS

Coverage of prescription drugs is important for improving access to essential medications for persons with the studied chronic conditions. A Medicare drug benefit that provides unimpeded access to medications needed to treat such conditions may improve medication acquisition and, ultimately, health.

Age-related disparities in cancer screening: analysis of 2001 Behavioral Risk Factor Surveillance System data

PURPOSE

Although few studies have explored age-related health care disparities, some researchers have asserted such disparities uniformly disfavor the elderly and are largely attributable to ageism in the health care system. We compared age-related patterns of screening for colorectal cancer with those for breast and prostate cancer in persons aged 50 years and older.

METHODS

We analyzed data for all adults aged 50 years and older (N = 88,213) in the 2001 Behavioral Risk Factor Surveillance System (BRFSS), a nationally representative, telephone-administered survey of personal health behaviors. Main outcome measures were adjusted prevalence by 5-year age-groups of colorectal cancer screening using fecal occult blood testing, flexible sigmoidoscopy, or colonoscopy for men and women; rates of mammography screening for women; and rates of prostate-specific antigen (PSA) screening for men.

RESULTS

After adjustment for race/ethnicity, education level, income, health insurance, and self-rated health, predicted reported colorectal cancer screening (all modalities) increased significantly from when patients reached age 50 years until 70 to 74 years (66.0%, standard error [SE] 0.8%), remained constant until age 80 years, and then declined. The age-related gain in colorectal cancer screening was confined to whites among patients older than 60 years. Reported PSA screening increased until age 75 to 79 years (79.3%, SE 1.1%) and then declined, whereas reported mammography screening peaked at age 55 to 59 years (83.3%, SE 1.2%) and then declined.

CONCLUSIONS

Significant age-related disparities appear to exist for both evidence-based and non-evidence-based cancer-screening interventions. The issue of age-related disparities in cancer screening is complex, with the direction of disparity favoring the elderly for some services yet disfavoring them for others.

Seniors with chronic health conditions and prescription drugs: benefits, wealth, and health

OBJECTIVES

The objectives of this study were to examine the relationship between prescription benefit status and access to medications among Medicare beneficiaries with hypertension, congestive heart failure, coronary artery disease, and diabetes and to determine how income, wealth, and health status influence this relationship.

METHODS

We analyzed survey and administrative data for 4492 Medicare + Choice enrollees aged 67 and above enrolled in a predominantly group-model health maintenance organization in 2000. Outcome measures included difficulty affording medications, methods of coping with medication costs including obtaining medicines from another country, using free samples, and stretching out medications to make them last longer. Independent variables included prescription benefit status, income, wealth measures, health status, and out-of-pocket prescription drug spending.

RESULTS

Lacking a prescription benefit was independently associated with difficulty affording medications (25% of those without a benefit vs. 17% with a benefit) and coping methods such as stretching out medications. Lower income, lower assets, and worse health status also independently predicted greater difficulty as measured by these outcomes; there was no effect modification between these factors and benefit status. Relative to national figures, out-of-pocket spending in this setting was quite low, with only 0.2 and 13% of those with and without a benefit, respectively, spending over 100 dollars per month. Higher out-of-pocket spending predicted greater difficulty affording medications but not stretching out medications.

CONCLUSIONS

Efforts to improve medication accessibility for older Americans with chronic conditions need to address not only insurance coverage but also barriers related to socioeconomic status and health status.

Spontaneous rupture of a true uterine artery aneurysm: a cause of retroperitoneal haematoma

We report the first case of spontaneous rupture of a true uterine artery aneurysm in a 69-year-old woman presenting with severe abdominal pain, a left iliac fossa mass, anaemia and a retroperitoneal haematoma on CT scanning. In this patient, the aneurysm was successfully embolised using microcoils. The different imaging modalities used for diagnosis and the treatment options are discussed.

Pathogen inactivation of platelet concentrates and fresh frozen plasma

Transfusion of blood products carries the risk of pathogen transmission, despite careful donor selection and screening tests. This is due to viral transmission from window-period donations, the emergence of new pathogens such as variant Creutzfeldt-Jakob disease, for which routine screening tests are not yet available, and to bacterial contamination. Techniques have been developed to inactivate pathogens in both fresh frozen plasma and platelet concentrates. The relative benefits to the recipient, and the ease of incorporation into blood component processing are considered for the technologies currently available.

Should asymptomatic patients with hereditary haemorrhagic telangiectasia (HHT) be screened for cerebral vascular malformations? Data from 22,061 years of HHT patient life

BACKGROUND

The frequency of haemorrhage in individuals with hereditary haemorrhagic telangiectasia (HHT), 10% of whom will have cerebral arteriovenous (AV) malformations, could be high enough to justify screening. This would allow presymptomatic treatment to prevent early onset stroke in a condition that affects at least 1 in 8000 individuals. This is an important issue in view of the contrast between transatlantic management approaches, the worldwide dissemination of patient information, and the ethical implications of the diagnosis for the untreated patient.

OBJECTIVES

To define the annual incidence of haemorrhagic stroke in individuals with HHT.

METHODS

Retrospective study on stroke incidence in individuals with HHT and their immediate families (n = 674; 22,061 HHT patient years), specifically analysing patients under 46 years of age (17,515 patient years). The results were compared with stroke risk in the general population.

RESULTS

In the majority of cases, the haemorrhage was the first significant neurological event. Overcorrecting for any bias towards overestimation that would be introduced in excluding non-penetrant family members, cerebral haemorrhages were more than 20 times more common in male HHT subjects under the age of 45 years than in the general population (standardised ratio 22.99; 95% confidence interval, 13.14 to 37.33). Haemorrhages were also six times more common in female HHT subjects (6.18; 2.27 to 13.45). The incidence ratio of cerebral haemorrhage in male patients (1.84; 1.05 to 2.99) yielded a haemorrhage rate in individuals with cerebral AV malformations of 1.4-2.0% per annum, comparable to figures in the non-HHT cerebral AV malformation population.

CONCLUSIONS

These data contradict accepted wisdom in many countries that asymptomatic HHT patients are at a low (and acceptable) risk of haemorrhage. The data justify a more aggressive screening approach to identify small causative lesions amenable to treatment.

Localization of gastrinomas by selective intra-arterial calcium injection

BACKGROUND

Preoperative localisation is important for successful surgical treatment of gastrinomas. However, a satisfactory method that achieves this has not been defined, and at present somatostatin receptor scintigraphy and selective intra-arterial stimulation testing with secretin have the greatest sensitivities. As secretin is now difficult to obtain, we decided to explore the use of calcium gluconate as a secretagogue. High extracellular calcium concentrations cause degranulation of neuroendocrine cells and subsequent release of hormone.

METHODS

Two patients with biochemically proven gastrinomas were investigated pre-operatively. Under angiographic control calcium gluconate was injected into the arteries supplying the pancreas and duodenum, gastrin levels were then determined in hepatic vein samples obtained before and 30, 60, 90, 120 and 180 seconds after each injection. One of the patients had also previously undergone selective intra-arterial stimulation testing with secretin.

RESULTS

Calcium gluconate produced sharp peaks of gastrin which unequivocally localised the tumour to a specific vascular territory in each case. Furthermore, surgery confirmed the localisations of the gastrinomas. Calcium injection, unlike secretin, into vascular territories without gastrinomas caused no rise in gastrin, thereby demonstrating calcium's greater specificity.

CONCLUSIONS

Calcium gluconate is a highly sensitive and specific alternative secretagogue to secretin for localisation of pancreatic and duodenal gastrinomas. Furthermore calcium gluconate was found to demonstrate the territory of the tumour more accurately than secretin.

Haemosuccus pancreaticus: treatment by arterial embolization

AIM

Haemosuccus pancreaticus is bleeding into the pancreatic duct from a peripancreatic artery. This condition most commonly follows pseudoaneurysm formation secondary to acute or chronic pancreatitis. It is a rare disorder, challenging in both diagnosis and therapy. We present an eight-year experience of managing these patients using endovascular embolization as the primary therapy.

MATERIALS AND METHODS

We retrospectively reviewed the imaging, laboratory results and clinical notes of the five patients who presented to this institution between 1991-1999 with gastrointestinal bleeding subsequently found to be haemosuccus pancreaticus.

RESULTS

There were four men and one women aged 38-75 years. All had a history of gastrointestinal haemorrhage and had acute (n=1) or chronic pancreatitis with a complicating pseudoaneurysm. All underwent embolization as the primary therapy for the pseudoaneurysm. There was immediate technical success in all cases without major complication. No patient required operative surgery for the pseudoaneurysm. Follow-up ranged from 18 months to 7 years. One patient died four years after embolization due to hepatic failure but the other four remain well without further gastrointestinal bleeding.

CONCLUSION

Endovascular embolization is an effective and safe treatment for haemosuccus pancreaticus.

Pulmonary arteriovenous malformations: effect of embolization on right-to-left shunt, hypoxemia, and exercise tolerance in 66 patients

OBJECTIVE

This study assessed the effect and safety of percutaneous transcatheter coil embolization of pulmonary arteriovenous malformations.

MATERIALS AND METHODS

In 58 (88%) of 66 patients, all malformations with feeding vessels greater than or equal to 3 mm in diameter were embolized with steel coils. Arterial oxygen saturation at rest and exercise, intrapulmonary right-to-left anatomic shunt fraction ((99m)Tc-macroaggregate injection), maximum exercise capacity (incremental work rate test), and pulmonary function were measured before and after embolization. Complications were analyzed.

RESULTS

Three categories of patients were identified. Patients in group 1 (27%) had complete occlusion of all angiographically visible pulmonary arteriovenous malformations; patients in group 2 (61%) had complete occlusion of all malformations with feeding vessels greater than or equal to 3 mm in diameter, but with smaller lesions persisting; and patients in group 3 (12%) had incomplete embolization, with feeding vessels greater than or equal to 3 mm in diameter remaining. The mean right-to-left shunt after embolization was least in group 1 (7%), intermediate in group 2 (10%), and greatest in group 3 (19%). Arterial oxygen saturation and right-to-left shunt fraction returned to normal levels (>96% and <3.5%, respectively) in 33% of patients. A significant improvement occurred after embolization in carbon monoxide diffusing capacity per unit of alveolar volume and in exercise capacity in 16 and 10 patients, respectively. In 93 procedures, 12 complications (13%) occurred.

CONCLUSION

Coil embolization of pulmonary arteriovenous malformations is effective in reducing right-to-left anatomic shunt fraction and in improving arterial oxygenation. Coil embolization of pulmonary arteriovenous malformations is well tolerated and has a low complication rate.

Investigation of vertebral "end plate sclerosis"

OBJECTIVE

To evaluate the association between vertebral "end plate sclerosis" and neck pain.

DESIGN

A retrospective study was carried out of lateral cervical spine radiographs with a Picture Archive and Communication System (PACS).

PATIENTS

Two hundred patients' files were randomly assessed, comprising four equal groups, A to D. The mean ages of the patients were 62+/-7.4 years, 61+/-7.5 years, 40+/-5.6 years and 23+/-5.6 years respectively. In group A, all patients had symptoms of neck pain and a radiographic diagnosis of "end plate sclerosis" of the cervical spine. In groups B to D, asymptomatic patients were recruited and their age groups were 50-69, 30-49 and 10-29 years respectively. Using the PACS, the radiographic density and the sagittal diameter, thickness and area of the end plates at the C5 level were measured.

RESULTS AND CONCLUSIONS

No significant differences were found in the radiographic density of the end plates either between the symptomatic and asymptomatic groups (groups A and B), or between different age groups (groups B, C and D). A significant increase in end plate area and thickness was found, however, in both group B (P<0.005) and group C (P<0.01) in comparison with group D. This indicates that the extent of end plate sclerosis increases with age. Our results suggest that the radiographic density of cervical vertebral end plates correlates neither with neck pain nor with increasing age. The radiological sign of "end plate sclerosis" may be over-reported, further limiting its value in the assessment of patients with cervical spondylosis.

Building blocks for molecule-based magnets: a theoretical study of triplet-singlet gaps in the dianion of rhodizonic acid 1,4-dimethide and its derivatives

Reduction of 1,4-dimethylenecyclohexane-2,3,5,6-tetrone forms the title dianion 1(2-), which may also be formulated as the 1,4-dimethide of deprotonated rhodizonic acid. Substituted versions of this species, designed as a charged electronic analogue of dimethylenecyclobutadiene, are proposed as building blocks for assembly of molecule-based magnets. A possible mode of self-organization of their metal salts into 2-D structures with intermolecular ferromagnetic coupling is outlined. Full pi space CAS(14,12)/6-31+G//CAS(14,12)/ 6-31G calculations were performed to probe the ground spin state (singlet vs triplet) of 1(2-) as a function of substituent variations. This study has found that a triplet ground state preference as high as 4.5 kcal/mol may be achieved for the symmetrically coordinated dianion.