MR Imaging Features of Middle Cranial Fossa Encephaloceles and Their Associations with Epilepsy.

BACKGROUND AND PURPOSE: Middle cranial fossa encephaloceles are an increasingly recognized cause of epilepsy; however, they are also often encountered on neuroimaging in patients with no history of seizure. We characterized the MR imaging features of middle cranial fossa encephaloceles in seizure and nonseizure groups with the hope of uncovering features predictive of epileptogenicity. MATERIALS AND METHODS: Seventy-seven patients with middle cranial fossa encephaloceles were prospectively identified during routine clinical practice of neuroradiology at a tertiary care hospital during an 18-month period. Thirty-five of 77 (45%) had a history of seizure, 20/77 (26%) had temporal lobe epilepsy, and 42/77 (55%) had no history of seizures. Middle cranial fossa encephalocele features on MR imaging were characterized, including depth, area, number, location, presence of adjacent encephalomalacia, and degree of associated parenchymal morphologic distortion. MR imaging features were compared between the seizure and nonseizure groups. RESULTS: No significant difference in MR imaging features of middle cranial fossa encephaloceles was seen when comparing the seizure and nonseizure groups. Comparison of just those patients with temporal lobe epilepsy (n = 20) with those with no history of seizure (n = 42) also found no significant difference in MR imaging features. CONCLUSIONS: Anatomic MR imaging features of middle cranial fossa encephaloceles such as size, number, adjacent encephalomalacia, and the degree of adjacent parenchymal morphologic distortion may not be useful in predicting likelihood of epileptogenicity.

Temporal lobe magnetic resonance spectroscopic imaging following selective amygdalohippocampectomy for treatment-resistant epilepsy.

OBJECTIVES: Magnetic resonance spectroscopic imaging (MRSI) may show circumscribed or extensive decreased brain N-acetyl aspartate (NAA)/creatine and phosphocreatine (Cr) in epilepsy patients. We compared temporal lobe MRSI in patients seizure-free (SzF) or with persistent seizures (PSz) following selective amygdalohippocampectomy (SAH) for medically intractable mesial temporal lobe epilepsy (mTLE). We hypothesized that PSz patients had more extensive temporal lobe metabolite abnormalities than SzF patients. MATERIALS AND METHODS: MRSI was used to study six regions of interest (ROI) in the bilateral medial and lateral temporal lobes in 14 mTLE patients following SAH and 11 controls. RESULTS: PSz patients had more temporal lobe ROI with abnormally low NAA/Cr than SzF patients, including the unoperated hippocampus and ipsilateral lateral temporal lobe. CONCLUSION: Postoperative temporal lobe MRSI abnormalities are more extensive if surgical outcome following SAH is poor. MRSI may be a useful tool to improve selection of appropriate candidates for SAH by identifying patients requiring more intensive investigation prior to epilepsy surgery. Future prospective studies are needed to evaluate the utility of MRSI, a predictor of successful outcome following SAH.

Effects of topiramate and gabapentin on cognitive abilities in healthy volunteers.

OBJECTIVE: To evaluate the cognitive effects of topiramate (TPM) and gabapentin (GBP). METHODS: Forty healthy volunteers were randomized to a 12-week course of TPM, GBP, or placebo. Doses were gradually escalated over 10 weeks to a maximum of 400 mg/day of TPM or 3,600 mg/day of GBP or to the highest tolerated dose. Subjects were interviewed and examined biweekly. Cognitive testing was performed prior to initiating the drug and again 12 weeks later, at least 2 weeks after achieving plateau dosing. For each subject and cognitive measure, test-retest Z scores were calculated based on regression equations derived from 73 healthy volunteers. Group comparisons utilized the Wilcoxon test. RESULTS: There were significant TPM vs GBP and TPM vs placebo differences in test-retest Z scores for four of six target cognitive measures (Digit Symbol, Story Recall, Selective Reminding, Controlled Oral Word Association), always indicating worse retest performance for subjects receiving TPM. Overall, 12 of 24 cognitive measures were similarly affected. TPM effects were large, and several target measures averaged >2 SD of negative change. One measure was significantly affected by GBP. CONCLUSIONS: Topiramate (TPM) impaired cognitive test performance, whereas gabapentin had minimal effects. The effects of TPM were of sufficient magnitude potentially to affect daily and occupational function.

Effects of oxcarbazepine and phenytoin on the EEG and cognition in healthy volunteers.

We studied the EEG and cognitive effects of oxcarbazepine (OXC) and phenytoin (PHT) using a double-blind, randomized, parallel-group design. Thirty-two healthy volunteers received a maximum of 1200 mg of OXC or 360 mg of PHT. EEG and cognitive testing were performed at baseline and after 12 weeks of treatment. For each subject and measure, test-retest Z scores were calculated from regression equations derived from 73 healthy controls. Twenty-six subjects completed the study. Both the OXC and PHT groups had significant slowing of the EEG peak frequency and increased relative theta and delta power. Differences between AEDs (antiepileptic drugs) were not significant. Significant cognitive effects were seen on 5 of 20 measures, primarily measures of motor speed and reaction time. Again, there were no significant differences between AEDs. The only significant difference between AEDs was for the POMS-Vigor scale, favoring OXC. The small sample size may have contributed to the lack of significant differences between AEDs.

February 2000: Dementia with motor dysfunction in a patient with liver disease.

Acquired (non-Wilsonian) hepatocerebral degeneration (AHCD) is an irreversible neurological condition characterized by dementia, dysarthria, and motor disturbances. It has been described in patients with severe liver disease of many causes, and notably in patients with surgically or spontaneously created porto-systemic shunts. We report a case of AHCD in a patient with end-stage liver disease due to alcohol abuse and hepatitis C. In addition, this patient showed pathologic evidence of the less commonly reported "shunt myelopathy" in the absence of a surgically created porto-systemic shunt. The myelopathy was associated with a dramatic vacuolation involving especially the deep motor cortex. Electron microscopy suggested that the vacuolation was due mainly to disruption of abnormal astrocytes.

The role of the intracarotid amobarbital procedure in evaluation of patients for epilepsy surgery.

PURPOSE: To examine the role of the intracarotid amobarbital procedure (IAP) in the presurgical evaluation of patients with medically refractory localization-related epilepsy. METHODS: We retrospectively studied 111 patients who underwent cortical resective surgery at our center between 1991 and 1996. In patients with mesial temporal lobe epilepsy (mTLE), a presurgical determination of the epileptogenic zone was compared with localization based on IAP memory asymmetry scores, and with ultimate localization after resective surgery. In patients with neocortical or mesial frontal epilepsy, the IAP was evaluated for evidence of unilateral or bilateral poor memory performance. RESULTS: Of 68 patients with mTLE localized by noninvasive tests, 60 had concordant lateralized memory deficits on IAP. Eight patients had lateralized memory deficits on IAP that were discordant with noninvasive tests and with localization as determined by surgical outcome. All 11 mTLE patients requiring invasive EEG monitoring were correctly lateralized by IAP, including one patient in whom the noninvasive evaluation otherwise provided false lateralization. Of 32 patients with neocortical or mesial frontal lobe epilepsy, 21 displayed memory deficits on IAP. Of 10 patients with bilateral deficits, five had mesial frontal lobe epilepsy. In 13 patients with lateralized memory deficits, seven underwent electrode implantation in the mesial temporal lobe, and four ultimately underwent resection of an epileptogenic mesial temporal lobe in addition to a neocortical resection. CONCLUSIONS: In patients with mTLE, lateralized memory deficits on IAP usually confirm localization provided by noninvasive tests. However, in mTLE not well lateralized by the noninvasive evaluation, and in neocortical or mesial frontal epilepsy, the IAP may provide information regarding localization that ultimately alters surgical management.

The long-term outcome of patients with IgA nephropathy treated with fish oil in a controlled trial. Mayo Nephrology Collaborative Group.

It was reported previously that dietary fish oil supplementation retarded the progression of renal disease in patients with IgA nephropathy in a multicenter, placebo-controlled, randomized, 2-yr clinical trial. The aim of this study was to determine the long-term influence of fish oil treatment on renal progression in observations on the study cohort of 106 patients extending beyond the 2-yr trial. Renal function was assessed by serial serum creatinine and 24-h urine protein measurements. Vital, end-stage renal disease (ESRD), and BP status and treatment beyond completion of the 2-yr trial were determined. As in the trial, the primary end point was an increase of 50% or more in the serum creatinine, and the secondary end point was ESRD. After a mean follow-up of 6.4 yr, 46 patients-17 in the fish oil group versus 29 in the placebo group-reached the primary end point (P = 0.002), and 27 patients-eight in the fish oil group versus 19 in the placebo group-developed ESRD (P = 0.009). At the end of the 2-yr trial, 75 patients (45 fish oil, 30 placebo) remained at risk for the primary end point. This is also when the double-blind part of the trial ended, allowing physicians to stop supplements, switch original placebo-assigned patients to fish oil, and continue fish oil in original fish oil-assigned patients. A significantly greater number of nonsupplemented placebo patients developed the primary end point (P = 0.02) and ESRD (P = 0.003) compared with long-term supplemented fish oil patients. Conversely, more fish oil-supplemented patients had stable renal function than nonsupplemented patients (P = 0.02). By intention, BP control, primarily treated with angiotensin-converting enzyme inhibition, was equal in the fish oil and placebo groups. Proteinuria was modestly reduced in both groups. It is concluded that early and prolonged treatment with fish oil slows renal progression for high-risk patients with IgA nephropathy.

Clinical trials of interactive computerized patient education: implications for family practice.

A systematic review of randomized clinical trials was conducted to evaluate the acceptability and usefulness of computerized patient education interventions. The Columbia Registry, MEDLINE, Health, BIOSIS, and CINAHL bibliographic databases were searched. Selection was based on the following criteria: (1) randomized controlled clinical trials, (2) educational patient-computer interaction, and (3) effect measured on the process or outcome of care. Twenty-two studies met the selection criteria. Of these, 13 (59%) used instructional programs for educational intervention. Five studies (22.7%) tested information support networks, and four (18%) evaluated systems for health assessment and history-taking. The most frequently targeted clinical application area was diabetes mellitus (n = 7). All studies, except one on the treatment of alcoholism, reported positive results for interactive educational intervention. All diabetes education studies, in particular, reported decreased blood glucose levels among patients exposed to this intervention. Computerized educational interventions can lead to improved health status in several major areas of care, and appear not to be a substitute for, but a valuable supplement to, face-to-face time with physicians.

Development of an HIV clinical and research database for South Africa.

Health service restructuring in South Africa provides an opportunity to introduce appropriate Health Information System (HIS) technology. This is particularly relevant given the emerging HIV epidemic and the need to capture, translate and disseminate new experiences in HIV/AIDS care, support and clinical research. In 1994, a number of clinicians and health-care providers working in South Africa had begun to establish basic computerized databases to assist in research on HIV, but no standardized nomenclature or framework for collaboration was created. This paper describes a clinical and research database that could be used as an example for a standardized system by clinicians working in South Africa. The authors, with assistance from the National AIDS Research Programme of the Medical Research Council, created a prototype relational database using Microsoft Access. To test the prototype, 1057 HIV-positive patients from the infectious Disease Clinic at Johannesburg General Hospital were entered.

PIP: The restructuring of health services in South Africa presents an opportunity to introduce appropriate Health Information System technology to assist in research on HIV and AIDS. In 1994, a group of clinicians and health care providers, with assistance from the National AIDS Research Program of the Medical Research Council, initiated collaboration to establish basic computerized databases. The group proposed that data entered into the database should be captured as close to the point of care as possible, with connectivity to laboratory computers and assurance of confidentiality. The prototype relational database was designed using Microsoft Access. It includes tables on demographics, medical history, primary and secondary HIV indicators, medications, performance indicators, radiology results, laboratory findings, and vital statistics. To test the prototype, data on 1057 HIV-positive patients from the Infectious Disease Clinic at Johannesburg General Hospital were entered into the system. Among the data generated were a listing of the top 10 opportunistic infections, the average absolute CD4 count within a given time of the diagnosis of such an infection, and patient referral sources. If further field testing is successful, translation into a full database system, integration of restricted vocabulary coding, and distribution onto a client-server network are planned.

Investigation of tick-borne viruses as pathogens of humans in South Africa and evidence of Dugbe virus infection in a patient with prolonged thrombocytopenia.

In the course of investigating suspected cases of viral haemorrhagic fever in South Africa patients were encountered who had been bitten by ticks, but who lacked evidence of infection with Crimean-Congo haemorrhagic fever (CCHF) virus or non-viral tick-borne agents. Cattle sera were tested by enzyme-linked immunoassay to determine whether tick-borne viruses other than CCHF occur in the country. The prevalence of antibody in cattle sera was 905/2116 (42.8%) for CCHF virus, 70/1358 (5.2%) for Dugbe, 21/1358 (1.5%) for louping ill, 6/450 (1.3%) for West Nile, 7/1358 (0.5%) for Nairobi sheep disease, 3/625 (0.5%) for Kadam and 2/450 (0.4%) for Chenuda. No reactions were recorded with Hazara, Bahig, Bhanja, Thogoto and Dhori viruses. The CCHF findings confirmed previous observations that the virus is widely prevalent within the distribution range of ticks of the genus Hyalomma, while antibody activity to Dugbe antigen was detected only within the distribution range of the tick Amblyomma hebraeum. Cross-reactivity for the nairoviruses, Hazara, Nairobi sheep disease and Dugbe, was detected in serum samples from 3/72 human patients with confirmed CCHF infection, and serum from 1/162 other patients reacted monospecifically with Dugbe antigen. The latter patient suffered from febrile illness with prolonged thrombocytopenia.

An expert system for performance-based direct delivery of published clinical evidence.

OBJECTIVE: To develop a system for clinical performance improvement through rule-based analysis of medical practice patterns and individualized distribution of published scientific evidence. METHODS: The Quality Feedback Expert System (QFES) was developed by applying a Level-5 expert system shell to generate clinical direct reports for performance improvement. The system comprises three data and knowledge bases: 1) a knowledge base of measurable clinical practice parameters; 2) a practice pattern database of provider-specific numbers of patients and clinical activities; and 3) a management rule base comprising "redline rules" that identify providers whose practice styles vary significantly. Clinical direct reports consist of a table of practice data highlighting individual utilization vs recommendation and selected pertinent statements from medical literature. RESULTS: The QFES supports integration of recommendations from several guidelines into a comprehensive and measurable quality improvement plan, analysis of actual practice patterns and comparison with accepted recommendations, and generation of a confidential individualized direct report to those who significantly deviate from clinical recommendations. The feasibility of the practice pattern analysis by the QFES was demonstrated in a sample of 182 urinary tract infection cases from a primary care clinic. In a set of clinical activities, four questions/procedures were associated with significant (p < 0.001) and unexplained variation. CONCLUSION: The QFES provides a flexible tool for the implementation of clinical practice guidelines in diverse and changing clinical areas without the need for special program development. Preliminary studies indicate utility in the analysis of clinical practice variation and deviations. Using data obtained through a retrospective chart audit, the QFES was able to detect overutilization, and to identify nonrandom differences in practice patterns.

Assessing the quality of primary care: the use and importance of reimbursement data.

Although inpatient quality assessment efforts have advanced greatly in recent years, similar growth has not yet been experienced in ambulatory care. However, given the growth of primary care and its role in managed care systems, the need for quality assessment innovations is great and the future looks promising. The authors describe their experience in developing such an innovation in an ambulatory care setting. The goal of this article is to identify and describe how secondary data--in particular, data from reimbursement systems--may be used to develop a primary care quality of care assessment system. This investigation highlights the importance of reimbursement data in developing clinically meaningful and practical models for quality assessment.

A controlled trial of fish oil in IgA nephropathy. Mayo Nephrology Collaborative Group.

BACKGROUND: The n-3 fatty acids in fish oil affect eicosanoid and cytokine production and therefore have the potential to alter renal hemodynamics and inflammation. The effects of fish oil could prevent immunologic renal injury in patients with IgA nephropathy. METHODS: In a multicenter, placebo-controlled, randomized trial we tested the efficacy of fish oil in patients with IgA nephropathy who had persistent proteinuria. The daily dose of fish oil was 12 g; the placebo was a similar dose of olive oil. Serum creatinine concentrations, elevated in 68 percent of the patients at base line, and creatinine clearance were measured for two years. The primary end point was an increase of 50 percent or more in the serum creatinine concentration at the end of the study. RESULTS: Fifty-five patients were assigned to receive fish oil, and 51 to receive placebo. According to Kaplan-Meier estimation, 3 patients (6 percent) in the fish-oil group and 14 (33 percent) in the placebo group had increases of 50 percent or more in their serum creatinine concentrations during treatment (P = 0.002). The annual median changes in the serum creatinine concentrations were 0.03 mg per deciliter (2.7 mumol per liter) in the fish-oil group and 0.14 mg per deciliter (12.4 mumol per liter) in the placebo group. Proteinuria was slightly reduced and hypertension was controlled to a comparable degree in both groups. The cumulative percentage of patients who died or had end-stage renal disease was 40 percent in the placebo group after four years and 10 percent in the fish-oil group (P = 0.006). No patient discontinued fish-oil treatment because of adverse effects. CONCLUSIONS: In patients with IgA nephropathy, treatment with fish oil for two years retards the rate at which renal function is lost.

Essential fatty acid deficiency profiles in idiopathic immunoglobulin A nephropathy.

The profiles of fatty acids (FAs) of plasma phospholipids (the compartment reflecting the essential FA status of tissue lipids), nonesterified FAs (the precursor pool for autacoid synthesis), urine protein excretion, and glomerular filtration rate were measured before and after supplementation with fish oil in 15 patients with immunoglobulin A nephropathy. In the FA profiles, there was deficient 18:3 omega 3 (alpha-linolenic acid), the parent compound of omega 3 polyunsaturated FA, and deficient chain elongation products of both omega 3 and omega 6 polyunsaturated FAs with replacement by saturated and monounsaturated short-chain, odd-chain, and branched-chain FAs, producing significant loss of omega 3 FA. These alterations indicate nutritional or functional (omega 3) and metabolic (omega 6) deficiencies. Additionally, the mean melting point of the FAs was significantly increased, implying an inherent decrease in cell membrane fluidity. Enhancement of 20: 5 omega 3 (eicosapentaenoic acid) and 22:6 omega 3 (docosahexaenoic acid) and suppression of 20:4 omega 6 (arachidonate) after supplementation with fish oil were accompanied by important decreases in proteinuria and improved glomerular filtration rate. Omega-3 polyunsaturated FAs may favorably influence immunoglobulin A nephropathy through a modulation of the pathologic actions of the omega 6 eicosanoids and other diverse actions on various mediators produced by an initial immune injury.

Clinical and histopathologic associations with impaired renal function in IgA nephropathy. Mayo Nephrology Collaborative Group.

A multicenter, double-blind, placebo-controlled, randomized trial of fish oil in proteinuric patients with IgA nephropathy is being conducted by the Mayo Nephrology Collaborative Group. We completed enrollment of 106 patients into the trial in December 1991. The treatment period is for two years. Hypertension is being managed in all patients with enalapril maleate (Vasotec). We evaluated the associations between a variety of clinical and renal morphologic features and renal function at the entry of all enrolled patients. Among 78 males and 28 females [age(mean +/- SD) 36 +/- 14 years], older age at treatment randomization, hypertension, at disease discovery as well as at study entry, increased fractional excretion of albumin, increased serum triglyceride levels, and more severe tubulointerstitial, vascular, and combined glomerular and tubulointerstitial histologic lesions were all univariately associated (p < or = 0.01) with poorer renal function measured by reciprocal serum creatinine and creatinine clearance levels. In a multiple regression analysis used to predict baseline reciprocal creatinine, the best final model (R2 = 0.48) included male sex (p < .001), hypertension at treatment randomization (p = .001), decreased peripheral blood erythrocytes (p = .001), increased tubulointerstitial score (p = .004), and increased fractional excretion of albumin (p = .025) as independent predictors of decreased kidney function. These associations are similar to those seen in the high-risk subset of patients with IgA nephropathy who develop end-stage renal disease. In the eventual outcome analysis of the clinical trial, we will examine the effects of treatment on the two potentially modifiable risk factors, hypertension and proteinuria, on renal function.