The role of perfusion and diffusion MRI in the assessment of patients affected by probable idiopathic normal pressure hydrocephalus. A cohort-prospective preliminary study.

BACKGROUND: Invasive tests measuring resistance to cerebral spinal fluid (CSF) outflow and the effect of temporary drainage of CSF are used to select candidates affected by idiopathic normal pressure hydrocephalus (iNPH) for shunt surgery. Neither test, however, completely excludes patients from treatment. Perfusion and diffusion magnetic resonance imaging (MRI) are non-invasive techniques that might be of value in selecting patients for surgical treatment and understanding brain changes in iNPH patients. The aim of this study was to understand the role of perfusion and diffusion MRI in selecting candidates for shunt surgery and to investigate the relationship between cerebral perfusion and possible microstructural changes in brain tissue before and after invasive tests, and after ventricular-peritoneal (VP) shunt implantation, to better clarify pathophysiological mechanisms underlying iNPH. METHODS: Twenty-three consecutive patients with probable iNPH were included in this study. Patients underwent a clinical and neuroradiological evaluation before and after invasive tests, and after surgery. Only patients who showed a positive result in at least one of the invasive tests were submitted for VP shunt implantation. Perfusion and diffusion magnetic resonance imaging (MRI) was performed before and after invasive tests and after shunt surgery. RESULTS: Thirteen patients underwent surgery and all showed clinical improvement after VP shunt implantation and a significant increase in perfusion in both periventricular white matter (PVWM) and basal ganglia (BG) regions. The 10 patients that did not have surgery showed after invasive tests, a significant reduction in perfusion in both PVWM and BG regions. Comparing the changes in perfusion with those of diffusion in positive patients we found a significant positive correlation in BG and a significant inverse correlation in PVWM area. CONCLUSIONS: Perfusion MRI is a non-invasive technique that could be useful together with invasive tests in selecting patients for surgical treatment. Furthermore, the relationship between perfusion and diffusion data could better clarify pathophysiological mechanisms underlying iNPH. In PVWM area we suggest that interstitial edema could reduce microvascular blood flow and interfere with the blood supply to these regions. In BG regions we suggest that a chronic hypoxic insult caused by blood hypo-perfusion produces a chronic cytotoxic edema. Both in PVWM and in BG regions, pathophysiological mechanisms could be modified after VP-shunt implantation.

The prevalence of vegetative and minimally conscious states: a systematic review and methodological appraisal.

OBJECTIVES: To systematically review prevalence studies of vegetative state (VS) and minimally conscious state (MCS) in geographically defined populations, to appraise study methods and assess sources of heterogeneity. METHODS: MEDLINE, EBM Reviews, and EMBASE databases were searched using key terms. Two reviewers independently identified pertinent articles and screened the references for additional studies. Studies measuring the prevalence of VS and/or MCS in a defined population were included, and information on characteristics, methods, and results was extracted. Heterogeneity was quantified through the statistic I. RESULTS: We identified 5 cross-sectional prevalence surveys of VS and 1 of MCS. Prevalence ranged from 0.2 cases per 100,000 inhabitants to 3.4 for VS and was 1.5 per 100,000 for MCS. Relevant heterogeneity (I = 99.0%) prevented us from calculating a summary estimate. The prevalence of trauma cases varied from 21.9% to 53.8%. Variability pertaining to diagnostic criteria, definition of case, and methods of ascertainment was found. CONCLUSION: In the few prevalence studies of VS and MCS that were identified, the estimates showed high variability and could not be pooled. Future studies should consider using comparable methods for the definition, ascertainment, and confirmation of cases.

Accuracy of International Classification of Diseases, 9th Revision, Clinical Modification codes for upper gastrointestinal complications varied by position and age: a validation study in a cohort of nonsteroidal anti-inflammatory drugs users in Friuli Venezia Giulia, Italy.

PURPOSE: To validate the International Classification of Diseases, 9th Revision, Clinical Modification discharge codes used to identify cases of upper gastrointestinal complications (UGICs) in hospitals of Friuli Venezia Giulia, Italy. METHODS: Cohort study on the risk of UGIC in users of nonsteroidal anti-inflammatory drugs conducted in Friuli Venezia Giulia between 2001 and 2008. Cases were identified through primary and secondary International Classification of Diseases, 9th Revision Clinical specific codes 531 (gastric ulcer), 532 (duodenal ulcer), 533 (peptic ulcer), 534 (gastrojejunal ulcer), and nonspecific code 578 (gastrointestinal hemorrhage). Potential cases were confirmed through hospital chart review. RESULTS: The chart retrieval percentage was 98.4%.The positive predictive value (PPV) was 94.3% for primary codes 531 and 532, 79.5% for code 533, 83.1% for code 534, 40.2% for code 578. The PPV for secondary codes was 34.7% but increased to 88.9% and 79.2% when the primary code was for peritonitis or acute post-hemorrhagic anemia, respectively. Validation of secondary codes increased case ascertainment by 4.9%. Endoscopy confirmed 79.4% of cases but only 67.2% of those above age 84 years. CONCLUSIONS: The PPV was high for specific primary codes and moderate to low for nonspecific primary and secondary codes. The inclusion of confirmed cases identified by nonspecific and secondary codes can be of value in studies that need a complete ascertainment of cases occurring in the study population. In this cohort, not including these cases would underestimate the incidence of UGICs. A potential for case misclassification exists in particular in eldest ages.

The incidence of amyotrophic lateral sclerosis in Friuli Venezia Giulia, Italy, from 2002 to 2009: a retrospective population-based study.

BACKGROUND: We conducted a retrospective population-based study to estimate the incidence of amyotrophic lateral sclerosis (ALS) in Friuli Venezia Giulia, Italy, from 2001 to 2009. METHODS: Multiple sources were used for case ascertainment: Health databases, archives of the neurology departments and of the regional chapter of the Italian ALS Association. The diagnosis was validated through clinical documentation review. Crude and standardized incidence rates (IRs) per 100,000 person-years were calculated. RESULTS: We identified 262 incident ALS cases, 50.4% men, 4.2% familial. Half of the patients had spinal onset (56.8% in men) and 25.2% bulbar (29% in women). Bulbar onset had a similar frequency in women (31.7%) and men (31.5%) aged 67 or above at diagnosis. The crude IR was 2.72 (95% confidence interval, 95% CI, 2.39-3.05) and the male:female ratio 1.08. The IR peaked in the 65-74 age group, with a second increase in men 85 years and older. The IR standardized to the 2001 Italian population was 2.38 (95% CI 2.13-2.63) and to the 2000 European population 2.58 (95% CI 2.34-2.81). CONCLUSIONS: This retrospective study found IRs of ALS in the range of Italian and European prospective population-based registries, suggesting an almost complete case ascertainment.

Risk of upper gastrointestinal complications in a cohort of users of nimesulide and other nonsteroidal anti-inflammatory drugs in Friuli Venezia Giulia, Italy.

PURPOSE: Information on the risk of upper gastrointestinal complications (UGIC) in users of nimesulide, the most used nonsteroidal anti-inflammatory drug (NSAID) in Italy, is scarce. In the context of the European regulatory review on nimesulide, we estimated and compared the risk associated with nimesulide and other individual NSAIDs with the risk in nonusers. METHODS: We used 2001-2008 data from regional health databases in Friuli Venezia Giulia (FVG), Italy, to conduct a cohort and nested case-control study of users of NSAIDs. Cases were identified by specific and nonspecific hospital discharge diagnoses in primary and secondary position and validated through hospital records. Ten controls per case were selected using density-based sampling from the cohort. Conditional logistic regression was used to estimate adjusted relative risks (RRs) and 95% confidence intervals (CIs). RESULTS: The cohort included 588,827 NSAIDs users and 3031 UGIC cases. Nonspecific codes contributed to 23% of cases and secondary codes to 5%. Among current users, IR per 1000 person-years decreased from 4.45 cases in 2001 to 2.21 cases in 2008. The RR (95%CI) for current use of NSAIDs was 3.28 (2.86, 3.76). RR was <2 for rofecoxib, celecoxib, and nimesulide; 2 to <5 for naproxen, ibuprofen, diclofenac, etoricoxib, and meloxicam; and ≥ 5 for ketoprofen, piroxicam, and ketorolac. CONCLUSIONS: IRs of UGIC in FVG decreased about 50% between 2001 and 2008. Nimesulide was in the low-medium range of RR. A complete ascertainment of UGIC cases in databases may require validation of nonspecific codes, secondary codes, and additional codes such as peritonitis and acute posthemorrhagic anemia.

Prognostic power of pre- and postoperative B-type natriuretic peptide levels in patients undergoing abdominal aortic surgery.

OBJECTIVES: The first aim of the present study was to evaluate the pre- and postoperative B-type natriuretic peptide (BNP) levels in patients undergoing surgery for repair of an infrarenal abdominal aortic aneurysm (AAA) and analyze their power as a predictor of in-hospital cardiac events. The second aim was to evaluate the association among pre- and postoperative BNP levels, postoperative patient complications, and length of hospital stay. DESIGN: Prospective observational study. SETTING: A university hospital. PARTICIPANTS: Forty-five patients undergoing elective surgery for an abdominal aortic aneurysm. INTERVENTIONS: The plasma BNP level was assessed just before surgery and then on postoperative day 1. Cardiac troponin I levels were measured postoperatively on arrival to the intensive care unit (time 0) and then 12, 48, and 72 hours later. MEASUREMENTS AND MAIN RESULTS: The preoperative BNP concentration in patients who developed an acute myocardial infarction was 209 (IQR 84-346) pg/mL compared with 74 (IQR 28-142) pg/mL in those who did not. The difference between groups was statistically significant (p = 0.04). The Spearman correlation showed that postoperative BNP levels correlated significantly with preoperative BNP levels (r = 0.73, p = 0.0001), length of hospital stay (r = 0.35, p = 0.04), and troponin I concentration at 0 hour (r = 0.42, p = 0.02), 12 hours (r = 0.51, p = 0.0052), and 48 hours (r = 0.40, p = 0.033). In contrast, preoperative BNP levels correlated with troponin I at only 12 hours (r = 0.34, p = 0.02). Postoperative BNP levels were influenced significantly by transfusions (p = 0.035) and cross-clamping times (p = 0.038). CONCLUSIONS: The present results confirm the high negative predictive value of preoperative BNP levels; and postoperative BNP levels showed a better correlation with postoperative troponin levels, blood transfusion, and postoperative cardiac events.

Wake-up test decrease shunts insertion during carotid endarterectomy under general anesthesia.

OBJECTIVE: The use of locoregional anesthesia versus general anesthesia (GE) in carotid endarterectomy (CEA) has been a debatable issue in clinical studies for the past several years. In our study, GE with wake-up tests (WUTs) during carotid cross-clamping was used instead of stump pressure (SP) to directly assess the neurological status of the patient to determine whether shunting was needed. Our study assessed the percentage of patients under light sedation and mechanically ventilated needing shunting based on WUT compared to a systolic stump pressure (SPs) cutoff value of

The accuracy of discharge diagnosis coding for Amyotrophic Lateral Sclerosis in a large teaching hospital.

To evaluate the accuracy of hospital discharge data as a source of Amyotrophic Lateral Sclerosis (ALS) cases for epidemiological studies or disease registries, a validation study was performed. All records of patients discharged in 2005 and 2006 with principal or secondary International Classification of Diseases, 9th rev., Clinical Modification (ICD 9 CM) diagnosis code of ALS (335.20), other anterior horn cell disease (335), spinal cord disease (336), hereditary and idiopathic peripheral neuropathy (356), inflammatory and toxic neuropathy (357), myoneural disorders (358), muscular dystrophies and myopathies (359), were selected from the electronic archive of discharge data of the University Hospital of Udine, Friuli Venezia Giulia Region, North East Italy. Corresponding clinical documentation was reviewed to ascertain the presence of El Escorial criteria, the gold standard. Sensitivity of the ICD 9 CM discharge code 335.20 was 93% (95%CI: 82-99%) and decreased to 91% (95%CI: 77-98%) when suspect ALS was excluded. Specificity was 99% (95%CI: 97-99%). The ICD 9 CM discharge code 335.20 can identify a high percentage of hospitalizations of patients truly affected by ALS and of patients with no ALS, among selected neurological diagnostic codes. To ensure complete ALS case ascertainment, prospective population-based registries or epidemiologic studies require active prospective surveillance and use of multiple sources, among them hospital discharge archives can provide accurate information.