Anxiety in patients undergoing MR imaging

To determine and quantify the major sources of anxiety for patients undergoing magnetic resonance (MR) imaging and to suggest means by which to eliminate or diminish their negative effects, the authors studied anxiety in 46 subjects. Of these, 20 randomly selected subjects who successfully completed the examination participated in exit interviews. Six subjects who terminated the examination before completion also completed exit interviews. Pre-imaging and postimaging questionnaires (state-trait anxiety inventory) were administered to measure anxiety in the 20 other subjects. Anxiety was associated with the constrictive dimensions of the magnet bore, examination duration, coil noise, and temperature within the bore. Preparation at the point of referral was consistently absent, incomplete, or misleading. Patients used identifiable strategies to cope with the examination: blinding, breathing relaxation techniques, visualization of pleasant images, and performance of mental exercises.     

Ghosal syndrome – genetics unveiled

Thromboxane synthase mutations in an increased bone density disorder (Ghosal syndrome)
Geneviève et al. (2008)
Nature Genetics 40(3):284–286     

Occult cerebral vascular malformations: high-field MR imaging

Occult cerebral vascular malformations (OCVMs) have characteristic appearances on high-field magnetic resonance (MR) images. These consist of circumscribed regions of low intensity, most prominent on T2-weighted images and representing hemosiderin deposits. Interspersed within most of these lesions are multiple areas of various signal intensity patterns, which correspond to hematomas in different stages of evolution and to fibrous regions containing calcium as well as hemosiderin. Forty-six lesions were found in 19 patients (34 supratentorial and 12 infratentorial). The supratentorial lesions tended to be subcortical or periventricular. Computed tomography depicted 24 of the 46 lesions demonstrated by high-field MR. Comparison of images obtained with both low-field MR (0.12 T and 0.35 T) and high-field MR (1.5 T) revealed that high-field MR imaging was superior in depicting OCVMs. High-field MR appears to be both sensitive and specific for OCVMs and may obviate the need for possible biopsy of these lesions.     

Effacement of the fetal cisterna magna in association with myelomeningocele

The cisterna magna is effaced in association with myelomeningocele. The authors retrospectively investigated the size of the fetal cisterna magna as a predictor of fetal myelomeningocele in 67 pregnant women (17-38 menstrual weeks) referred for prenatal sonography because of an elevated serum alpha-fetoprotein level (n = 61) or a suspicion of fetal ventriculomegaly on previously obtained sonograms (n = 6). Twenty fetuses had myelomeningocele, 14 had isolated ventriculomegaly, and 33 were normal. A normal-sized cisterna magna (range, 4-9 mm in depth) was present in all normal fetuses. In 19 of 20 fetuses with myelomeningocele, the views of the posterior fossa were adequate, and in each of these the cisterna magna was effaced (n = 18) or very small (n = 1). The cisterna magna was effaced in five of 13 (38%) fetuses with isolated ventriculomegaly in whom the posterior fossa was adequately imaged. Although effacement of the cisterna magna is a nonspecific finding, the high negative predictive value of this sign is useful during routine screening of the fetal neural axis.     

Cytomegalovirus-seronegative blood components for the prevention of primary cytomegalovirus infection after marrow transplantation. Considerations for blood banks

The authors report 2.5 years' experience with the use of cytomegalovirus (CMV)-seronegative blood components for the prevention of primary CMV infection after allogeneic marrow transplantation from seronegative marrow donors to 104 CMV-seronegative patients. Patients and blood donors were screened for CMV-seronegativity by a combination of passive latex agglutination, complement fixation, and indirect hemagglutination CMV antibody screening methods. Changes in blood banking procedures necessary to provide CMV-seronegative components are detailed. Providing CMV-seronegative components was a considerable undertaking; a mean, per patient, of 19 units of red cells and 105 units of platelets was required. Twenty percent of the platelet support was provided by family members and 80 percent by volunteer donors. CMV-infection was eliminated in all but one patient not considered infected at the time of transplantation. The capability to provide CMV-seronegative components depends on an adequate supply of seronegative donors, a sensitive and practical screening method for CMV antibody, a major commitment by the blood bank, and close communication between the blood bank and the patients' physicians.     

Monitoring for undertransfusion

BACKGROUND: Most published reviews and audits of blood and blood component transfusion have focused on the issue of overtransfusion and on the inappropriate use of red cell components. There is growing concern that efforts to curb unnecessary transfusions may result in a trend toward undertransfusion of patients. There is little published information that addresses this issue or the magnitude of this practice. STUDY DESIGN AND METHODS: Undertransfusion was evaluated by examining the transfusion records from a 3-month period for 55 patients who met the study criteria of having either a hemoglobin level < 7 g per dL or a platelet count of < 10 × 10(9) per L. If the identified patient did not receive a transfusion within 24 hours of the reported hemoglobin level or platelet count, the medical record was reviewed by a resident physician. RESULTS: A total of 213 individual hemoglobin levels and platelet counts, representing the 55 patients, met our transfusion criteria. All except 8 of the identified patients received red cells and/or platelet transfusions. Reasons for not transfusing red cells included the patient's response to nutritional support and iron supplementation, refusal of blood, and noncompliance. Reasons for not transfusing platelets included falsely low platelet count because of platelet clumping in vitro, contraindication based on clinical diagnosis (e.g., immune thrombocytopenic purpura), and the patient's death before transfusion. CONCLUSION: Red cell and platelet transfusions were appropriately ordered for all patients who met the transfusion criteria. Undertransfusion is not a problem at this institution according to the criteria established. It is recommended that other institutions expand their blood utilization audits to include investigation for evidence of undertransfusion. Further research regarding the issue of undertransfusion is warranted and could be expanded to include other components.     

Informed Consent for Medical Research: Common Discrepancies and Readability

Objective: To identify common discrepancies and average reading grade levels for informed consent forms (ICFs) us submitted to institutional review boards (IRBs) by medical researchers.
Methods: A retrospective evaluation of ICFs as submitted to IRBs of 3 university-affiliated hospitals during a I-year period. ICF content was evaluated using a checklist of 23 requirements specified in the federal regulations governing human research. Documents then were computer-analyzed to determine the readability scores using 2 common indexes of comprehension. A discrepancy was defined as any instance in which an ICF did not address an applicable requirement in the Code of Federal Regulations.
Results: Eighty-two ICFs representing 16 medical specialties were evaluated; 8 (10%) were from emergency medicine. Eighteen ICFs (22%) were conspicuously incomplete, lacking 29 federal requirements. The mean number of discrepancies was 4.7 (95% CI, 3.9–5.5) Common omissions included: a statement about who is doing the research, number of subjects in the study, circumstances when a subject's participation may be terminated, disclosure of alternative procedures, and notice to subjects regarding new findings. The mean Flesch grade level required to read all ICFs was 13.8 (95% CI, 13.5–14.2), implying that the majority of the U.S. adult population would be unable to comprehend these forms.
Conclusion: Designing a consent form to meet all of the federal requirements while maintaining a level of reading comprehension suitable for the general population is a difficult task for investigators.     

The Importance of Early Carotid Endarterectomy in Symptomatic Patients

INTRODUCTION

Early carotid endarterectomy (CEA) in symptomatic patients may prevent repeat cerebral events. This study investigates the relationship between waiting time for CEA and the incidence of repeat cerebral events prior to surgery in symptomatic patients.

PATIENTS AND METHODS

A prospective database of consecutive patients undergoing CEA between January 2002 and December 2006 was reviewed. Repeat event rates prior to surgery were calculated using Kaplan–Meier analysis and predictive factors identified using Cox regression analysis.

RESULTS

A total of 118 patients underwent CEA for non-disabling stroke, TIA and amaurosis fugax. Repeat cerebral events occurred in 34 of 118 (29%) patients at a median 51 days (range, 2–360 days) after the first event. The estimated risk of repeat events was 2% at 7 days and 9% at 1 month after first event (Kaplan–Meier survival analysis). Age (HR 1.059; 95% CI 1.014–1.106; P = 0.009] was identified as a predictor of repeat events. Patients underwent surgery at median 97 days (range, 7–621 days) after the first event. Eleven of 60 (18%) patients waiting ≤?97 days for surgery and 23 of 58 (40%) patients waiting >?97 days had repeat events. (P = 0.011, chi-squared test).

CONCLUSIONS

Delays in surgery should be reduced in order to minimise repeat cerebral events in patients with symptomatic carotid stenosis, particularly in the elderly population.