Associations between HbA1c and continuous glucose monitoring-derived glycaemic variables.

AIMS: To identify clinically useful associations between HbA1c levels and various continuous glucose monitoring-derived metrics. METHODS: We retrospectively analysed end-of-study HbA1c levels and >2 weeks of continuous glucose monitoring data collected from 530 adults with Type 1 diabetes or insulin-requiring Type 2 diabetes during four randomized trials. Each trial lasted ≥24 weeks and provided central laboratory end-of-study HbA1c levels and continuous glucose monitoring data from the preceding 3 months. Participants were assigned to groups based on either HbA1c levels or continuous glucose monitoring-derived glucose values. RESULTS: HbA1c was strongly correlated with mean glucose value (r=0.80), time spent with glucose values in the 3.9-10.0 mmol/l range (time in range; r=-0.75) and percentage of glucose values >13.9 mmol/l (r=0.72), but was weakly correlated with the percentage of glucose values <3.9 mmol/l (r=-0.39) or <3.0 mmol/l (r=-0.21). The median percentage of glucose values <3.0 mmol/l was <1.2% (<20 min/day) for all HbA1c -based groups, but the median percentage of values >13.9 mmol/l varied from 2.5% (0.6 h/day) to 27.8% (6.7 h/day) in the lowest and highest HbA1c groups, respectively. More than 90% of participants with either <2% of glucose values >13.9 mmol/l, mean glucose <7.8 mmol/l, or time in range >80% had HbA1c levels ≤53 mmol/mol (≤7.0%). For participants with HbA1c ≥64 mmol/mol (≥8.0%), the median time in range was 44%, with 90% of participants having a time in range of <59%. CONCLUSIONS: The associations shown in the present study suggest that continuous glucose monitoring-derived metrics may help guide diabetes therapy intensification efforts in an HbA1c -independent manner.

Safety, efficacy and glucose turnover of reduced prandial boluses during closed-loop therapy in adolescents with type 1 diabetes: a randomized clinical trial.

AIMS: To evaluate safety, efficacy and glucose turnover during closed-loop with meal announcement using reduced prandial insulin boluses in adolescents with type 1 diabetes (T1D). METHODS: We conducted a randomized crossover study comparing closed-loop therapy with standard prandial insulin boluses versus closed-loop therapy with prandial boluses reduced by 25%. Eight adolescents with T1D [3 males; mean (standard deviation) age 15.9 (1.5) years, glycated haemoglobin 74 (17) mmol/mol; median (interquartile range) total daily dose 0.9 (0.7, 1.1) IU/kg/day] were studied on two 36-h-long visits. In random order, subjects received closed-loop therapy with either standard or reduced insulin boluses administered with main meals (50-80 g carbohydrates) but not with snacks (15-30 g carbohydrates). Stable-label tracer dilution methodology measured total glucose appearance (Ra_total) and glucose disposal (Rd). RESULTS: The median (interquartile range) time spent in target (3.9-10 mmol/l) was similar between the two interventions [74 (66, 84)% vs 80 (65, 96)%; p = 0.87] as was time spent above 10 mmol/l [21.8 (16.3, 33.5)% vs 18.0 (4.1, 34.2)%; p = 0.87] and below 3.9 mmol/l [0 (0, 1.5)% vs 0 (0, 1.8)%; p = 0.88]. Mean plasma glucose was identical during the two interventions [8.4 (0.9) mmol/l; p = 0.98]. Hypoglycaemia occurred once 1.5 h post-meal during closed-loop therapy with standard bolus. Overall insulin delivery was lower with reduced prandial boluses [61.9 (55.2, 75.0) vs 72.5 (63.6, 80.3) IU; p = 0.01] and resulted in lower mean plasma insulin concentration [186 (171, 260) vs 252 (198, 336) pmol/l; p = 0.002]. Lower plasma insulin was also documented overnight [160 (136, 192) vs 191 (133, 252) pmol/l; p = 0.01, pooled nights]. Ra_total was similar [26.3 (21.9, 28.0) vs 25.4 (21.0, 29.2) µmol/kg/min; p = 0.19] during the two interventions as was Rd [25.8 (21.0, 26.9) vs 25.2 (21.2, 28.8) µmol/kg/min; p = 0.46]. CONCLUSIONS: A 25% reduction in prandial boluses during closed-loop therapy maintains similar glucose control in adolescents with T1D whilst lowering overall plasma insulin levels. It remains unclear whether closed-loop therapy with a 25% reduction in prandial boluses would prevent postprandial hypoglycaemia.

Safety of closed-loop therapy during reduction or omission of meal boluses in adolescents with type 1 diabetes: a randomized clinical trial.

We evaluated the safety and efficacy of closed-loop therapy with meal announcement during reduction and omission of meal insulin boluses in adolescents with type 1 diabetes (T1D). Twelve adolescents with T1D [six male; mean (s.d.) age 15.9 (1.8) years; mean (s.d.) glycated haemoglobin (HbA1c) 77 (27) mmol/mol] were studied in a randomized crossover study comparing closed-loop therapy with meal announcement with conventional pump therapy over two 24-h stays at a clinical research facility. Identical meals were given on both occasions. The evening meal insulin bolus was calculated to cover half of the carbohydrate content of the meal and no bolus was delivered for lunch. Plasma glucose levels were in the target range of 3.9-10 mmol/l for a median [interquartile range (IQR)] of 74 (55,86)% of the time during closed-loop therapy with meal announcement and for 62 (49,75)% of the time during conventional therapy (p = 0.26). Median (IQR) time spent with plasma glucose levels > 10 mmol/l [23 (13,39) vs. 27 (10,50)%; p = 0.88] or < 3.9 mmol/l [1(0,4) vs. 5 (1,10)%; p = 0.24] and mean [standard deviation (SD)] glucose levels [8.0 (7.6,9.3) vs. 7.7 (6.6,10.1) mmol/l, p = 0.79] were also similar. In conclusion, these results assist home testing of closed-loop delivery with meal announcement in adolescents with poorly controlled T1D who miscalculate or miss meal insulin boluses.

Smoking in help-seeking veterans with PTSD returning from Afghanistan and Iraq.

Past research has shown that veterans and individuals with posttraumatic stress disorder (PTSD) have increased rates of smoking. However, the rates of smoking in younger help-seeking veterans returning from Afghanistan and Iraq, and possible correlates of smoking among this population are unknown. In this study, we evaluated the rate of lifetime and current smoking among a sample of 90 returning male veterans diagnosed with PTSD. Fifty-nine percent reported a lifetime history of smoking including 32% that were current smokers. Current smokers were significantly younger than non-smokers. Current smokers (mean age=31) reported a mean age of smoking onset as 15.86 with a pack year history of 8.89. These smokers reported on average five previous quit attempts. According to a stages of change model, one-half of the smokers were in the contemplation phase of stopping smoking (50%), 29% were in the pre-contemplation phase and 21% were in the preparation phase. The results are placed in the context of non-psychiatric and psychiatric smokers.

Comorbid posttraumatic stress disorder is associated with suicidality in male veterans with schizophrenia or schizoaffective disorder.

The purpose of this study was to determine if patients with schizophrenia or schizoaffective disorders and comorbid posttraumatic stress disorder (PTSD) are at higher risk for suicidality than patients without comorbid PTSD. Participants were 165 male veterans with primary diagnoses of schizophrenia or schizoaffective disorder. Those with comorbid PTSD reported higher rates of suicidal ideation and suicidal behaviors compared to those without comorbid PTSD. These findings suggest that patients with comorbid PTSD are at higher risk for suicidality. Enhanced screening and targeted interventions may be warranted to address comorbid PTSD and increased suicide risk in this population.

The relationship between hostility and behavioral risk factors for poor health in women veterans.

BACKGROUND: While previous research has generally supported a relationship between hostility and health risk behaviors, the majority of this research has been conducted in predominately male, highly educated, Caucasian samples. The current study was designed to further examine the relationship between hostility and health risk behaviors in a sample of women. METHODS: Measures of health risk behavior and scores from the Cook-Medley hostility scale were obtained from 409 women veterans. Linear and logistic regression analyses were used to examine the relationship between hostility and health behaviors including tobacco smoking, alcohol use, body-mass index, caffeine use, and level of physical activity, after sociodemographic factors were accounted for. RESULTS: In a cohort of women veterans using VA health care, ages 35-81, hostility was significantly associated with tobacco smoking (OR = 2.10; 95% CI = 1.34 to 3.30), caffeine use (OR = 2.12; 95% CI = 1.16 to 3.85), and the number of alcoholic beverages consumed by women who drink alcohol. Hostility was not associated with body mass index (OR = 1.15; 95% CI = 0.77 to 1.72) or a lack of physical exercise (OR = 0.89; 95% CI = 0.55 to 1.43). CONCLUSIONS: Results are generally consistent with previous research and support the relationship between hostility and health risk behaviors. Awareness that hostility contributes to risk behaviors and disease may help in the design of interventions aimed at risk reduction.

Drug use and validity of substance use self-reports in veterans seeking help for posttraumatic stress disorder.

The present study assessed drug use and the validity of self-reports of substance use among help-seeking veterans referred to a specialty clinic for the assessment of posttraumatic stress disorder (PTSD). Patients (n = 341) were asked to provide a urine sample for use in drug screening as part of an evaluation of PTSD. Self-reports of substance use were compared with same-day supervised urine samples for 317 patients who volunteered to participate in a drug screening. Results suggested that self-reports were generally quite valid. Only 8% of the cases involved patients not reporting substance use detected by urine screens. A total of 42% of the participants were identified as using drugs of abuse (excluding alcohol) through self-report and urine drug screens. Among participants using drugs, PTSD diagnosis was significantly associated with greater marijuana and depressant use as compared with stimulant (cocaine and amphetamines) use.

Feigning combat-related posttraumatic stress disorder on the personality assessment inventory.

This study examined whether individuals who were instructed on the Diagnostic and Statistical Manual of Mental Disorders (4th ed. [DSM-IV]; American Psychiatric Association, 1994) criteria for posttraumatic stress disorder (PTSD) could feign PTSD on the Personality Assessment Inventory (PAI; Morey, 1991). The study also investigated whether PAI indexes of symptom exaggeration, the Negative Impression Management (NIM) scale and the Malingering index, could identify individuals feigning PTSD. The diagnostic rule for PTSD (Morey, 1991, 1996) was applied to the profiles of a group of 23 veterans with combat-related PTSD and 23 male undergraduates instructed to malinger PTSD. Seventy percent of the student malingerers produced profiles that received diagnostic consideration for PTSD. The NIM cutting score (> or = 8) was highly effective in detecting simulation of PTSD but resulted in the misclassification of a large number of true PTSD cases. There were no significant differences in the overall efficiency of the test with various validity criteria. We discuss the implications of these findings for the use of the PAI in the diagnosis of combat-related PTSD.

Three-dimensional volume rendering of spiral CT data: theory and method.

Three-dimensional (3D) medical images of computed tomographic (CT) data sets can be generated with a variety of computer algorithms. The three most commonly used techniques are shaded surface display, maximum intensity projection, and, more recently, 3D volume rendering. Implementation of 3D volume rendering involves volume data management, which relates to operations including acquisition, resampling, and editing of the data set; rendering parameters including window width and level, opacity, brightness, and percentage classification; and image display, which comprises techniques such as "fly-through" and "fly-around," multiple-view display, obscured structure and shading depth cues, and kinetic and stereo depth cues. An understanding of both the theory and method of 3D volume rendering is essential for accurate evaluation of the resulting images. Three-dimensional volume rendering is useful in a wide variety of applications but is just now being incorporated into commercially available software packages for medical imaging. Although further research is needed to determine the efficacy of 3D volume rendering in clinical applications, with wider availability and improved cost-to-performance ratios in computing, 3D volume rendering is likely to enjoy widespread acceptance in the medical community.

Tracheal extubation of deeply anesthetized pediatric patients: a comparison of isoflurane and sevoflurane.

UNLABELLED: We studied the emergence characteristics of unpremedicated children tracheally extubated while deeply anesthetized ("deep extubation") with isoflurane or sevoflurane. Forty children were assigned to one of two groups, Group I or Group S. At the end of the operation, Group I patients were extubated while breathing 1.5 times the minimum alveolar anesthetic concentration (MAC) of isoflurane. Group S patients were tracheally extubated while breathing 1.5 times the MAC of sevoflurane. Recovery characteristics and complications were noted. Group S patients were arousable sooner than Group I patients (10.1 + 6.5 vs 16.3 + 9.9 min). Later arousal scores and times to discharge were the same. There were no serious complications in either group. Breath-holding was more common in Group I. We conclude that the overall incidence of airway problems and desaturation episodes was similar between groups. Emergency delirium was common in both groups (32% overall: 40% for Group I, 25% for Group S). IMPLICATIONS: Deep extubation of children can be safely performed with either isoflurane or sevoflurane. After deep tracheal extubation, airway problems occur but are easily managed. Return to an arousable state occurred more quickly with sevoflurane, although time to meeting discharge criteria was not different between the two groups. Emergence delirium occurs frequently with either technique.

Interactive three-dimensional volume rendering of spiral CT data: current applications in the thorax.

Spiral computed tomographic (CT) data sets coupled with a real-time volume-rendering technique allow creation of accurate three-dimensional (3D) images that can be used for a wide range of clinical applications. The image contrast of and relative pixel attenuations in the final image can be interactively modified by the user in real time by manipulating trapezoidal transfer functions. Although 3D images are not required for diagnosis, they aid both radiologists and referring clinicians by demonstrating anatomic relationships and the extent of disease, particularly for vessels oriented in the z axis. Three-dimensional imaging of the vasculature and airway structures has many advantages, including the potential to obviate invasive procedures such as angiography and bronchoscopy. Clinical applications of volume rendering of spiral CT data include cardiovascular imaging (aorta, pulmonary vasculature, and venous abnormalities), staging of thoracic neoplasms (mediastinal and pulmonary masses), tracheobronchial imaging, and imaging of chest wall disease.

Developing a computer-assisted instruction program: a process overview for the radiologist.

Recent advances in computer technology have led to the creation and development of computer-assisted instruction (CAI) programs, which are rapidly assuming a prominent role in both medical and nonmedical education. The development process includes defining objectives, identifying the target audience, assembling the design team, selecting compatible hardware and software, optimizing image quality, designing a palette, structuring information, and evaluating the program through user feedback. Although the individual radiologist is unlikely to possess all the skills necessary for developing a CAI program, even a basic knowledge of the computer environment is sufficient to enable him or her to become integrally involved in the process. The radiologist as "content expert" can and should participate actively throughout the process to integrate medical content with CAI program design. Indirect involvement might include participation in creative brainstorming sessions; direct involvement might help ensure image quality. A comprehensive understanding of the development process will enable the radiologist to communicate effectively as an educator in the new medium of CAI.

An interactive computer-based tool for teaching the segmental anatomy of the liver: usefulness in the education of residents and fellows.

OBJECTIVE: The purpose of this study was to develop an interactive computer-based tool for teaching hepatic segment anatomy and to evaluate its usefulness for radiology education. CONCLUSION: An interactive computer-based teaching tool has been developed that effectively teaches the segmental anatomy of the liver to radiology residents and fellows who have a wide range of baseline knowledge of hepatic anatomy.

The GI Project: a prototype electronic textbook for high school biology.

A prototype electronic science textbook for secondary education was developed to help bridge the gap between state-of-the-art medical technology and the basic science classroom. The prototype combines the latest in radiologic imaging techniques with a user-friendly multimedia computer program to teach the anatomy, physiology, and diseases of the gastrointestinal (GI) tract. The program includes original text, illustrations, photographs, animations, images from upper GI studies, plain radiographs, computed tomographic images, and three-dimensional reconstructions. These features are intended to create a stimulus-rich environment in which the high school science student can enjoy a variety of interactive experiences that will facilitate the learning process. The computer-based book is a new educational tool that promises to play a prominent role in the coming years. Current research suggests that computer-based books are valuable as an alternative educational medium. Although it is not yet clear what form textbooks will take in the future, computer-based books are already proving valuable as an alternative educational medium. For beginning students, they reinforce the material found in traditional textbooks and class presentations; for advanced students, they provide motivation to learn outside the traditional classroom.

Imaging of intrahepatic cholangiocarcinoma: 1. Peripheral cholangiocarcinoma.

Cholangiocarcinoma is the second most common primary hepatic malignant tumor after hepatocellular carcinoma, accounting for 5-30% of all primary hepatic malignant tumors [1]. Intrahepatic cholangiocarcinomas can be classified as peripheral cholangiocarcinoma, which originates from an interlobular biliary duct, or as hilar cholangiocarcinoma, which originates from a main hepatic duct or from the bifurcation of the common hepatic duct. Intrahepatic cholangiocarcinomas account for only about half of cholangiocarcinomas, and this pictorial essay focuses only on the peripheral form of the disease. Clinically, therapeutically, and radiologically, these two types of cholangiocarcinomas differ. Features suggestive of the diagnosis of peripheral cholangiocarcinoma can be shown by sonography, CT, and MR imaging. Cholangiography and angiography have a limited role in evaluating this neoplasm that manifests as a focal mass. This essay reviews the appearances of peripheral cholangiocarcinoma and discusses the various imaging techniques that can be used to evaluate this unusual tumor that is often resectable and potentially curable.

Imaging of intrahepatic cholangiocarcinoma: 2. Hilar cholangiocarcinoma.

Hilar cholangiocarcinoma (also called Klatskin's tumor) is more common than peripheral cholangiocarcinoma. Sonography, CT, MR imaging, angiography, and cholangiography can suggest the diagnosis, but the major issue of imaging with this tumor is to determine whether the tumor is resectable. The anatomic location of hilar cholangiocarcinoma makes resection difficult, so that surgical exploration of patients with this condition should be undertaken only when preoperative evaluation has shown a potential for curative resection. Preoperative assessment of resectability of hilar cholangiocarcinoma is often extensive, requiring several types of imaging. This pictorial essay reviews the imaging features of hilar cholangiocarcinoma. The role of imaging in the preoperative planning, with specific emphasis on staging extent of disease, including hepatic and vascular involvement, is discussed and illustrated.

CT of the esophagus: spectrum of disease with emphasis on esophageal carcinoma.

The esophagus is involved by a wide range of pathologic processes that can be detected, defined, and staged with computed tomography (CT). These processes include esophageal carcinoma; benign esophageal tumors; inflammatory and infectious diseases; miscellaneous conditions such as Barrett esophagus, achalasia, and varices; and trauma and perforation. CT is usually performed to clarify findings seen with other imaging modalities or to stage a pathologic condition; however, it may be the primary imaging modality in some cases. Because of the critical location of the esophagus, it can be involved secondarily by other disease processes or as part of a systemic process. By being aware of the appearances of the various entities that affect the esophagus, the radiologist can play an important role in detecting and staging esophageal disease. Although the role of CT in the evaluation of esophageal disease has been controversial, recent developments such as spiral CT have the potential to renew interest in this application.

Three-dimensional spiral CT during arterial portography: comparison of three rendering techniques.

The three most common techniques for three-dimensional reconstruction are surface rendering, maximum-intensity projection (MIP), and volume rendering. Surface-rendering algorithms model objects as collections of geometric primitives that are displayed with surface shading. The MIP algorithm renders an image by selecting the voxel with the maximum intensity signal along a line extended from the viewer's eye through the data volume. Volume-rendering algorithms sum the weighted contributions of all voxels along the line. Each technique has advantages and shortcomings that must be considered during selection of one for a specific clinical problem and during interpretation of the resulting images. With surface rendering, sharp-edged, clear three-dimensional reconstruction can be completed on modest computer systems; however, overlapping structures cannot be visualized and artifacts are a problem. MIP is computationally a fast technique, but it does not allow depiction of overlapping structures, and its images are three-dimensionally ambiguous unless depth cues are provided. Both surface rendering and MIP use less than 10% of the image data. In contrast, volume rendering uses nearly all of the data, allows demonstration of overlapping structures, and engenders few artifacts, but it requires substantially more computer power than the other techniques.

Spiral CT during arterial portography: technique and applications.

Spiral computed tomography during arterial portography (CTAP) combines rapid scanning with selective imaging during the portal phase of enhancement of the liver, resulting in an effective method for evaluation of liver neoplasms prior to partial hepatic resection. Compared with dynamic incremental CTAP, spiral CTAP results in improved quality of three-dimensional and multiplanar reconstructions, facilitating presurgical planning. Accurate volumetric analysis of the tumor can be performed, and subsegmental tumor localization is facilitated by the high levels of hepatic and portal venous enhancement. Additional advantages of spiral CTAP include small reconstruction intervals for improved lesion detection. However, the specificity of spiral CTAP is low because both benign and malignant tumors appear as hypoattenuating perfusion defects. In addition, both focal and geographic nontumorous perfusion defects may be seen more frequently with spiral CTAP than with dynamic CTAP. Knowledge of common diagnostic pitfalls is necessary for accurate interpretation of spiral CTAP images.

Comparison of laparoscopic and minilap cholecystectomy for acute cholecystitis.

The charts of all patients with acute cholecystitis undergoing either laparoscopic or minilap cholecystectomy at the Chinle Comprehensive Health Care Facility between October 1, 1991, and August 15, 1993, were retrospectively reviewed. During that period, 54 patients underwent laparoscopic cholecystectomy and 45 patients had minilap procedures. The two groups had similar mean age, sex distribution, temperature, leukocyte count, gallbladder wall thickness, and duration of preoperative symptoms. While laparoscopic cholecystectomy took an average of 16 min longer to perform than minilap cholecystectomy, patients who had laparoscopic cholecystectomy had less blood loss, reduced postoperative narcotic needs, and shorter hospital stays.