What Should Be Considered to Cause the Early Post-Craniotomy Seizure: Antibiotics (Cefazolin) Irrigation

Objective

Post-craniotomy seizure (PCS) is reported only rarely. However, our department noted a 433% increase in PCS for a year beginning September 2010, especially after cerebrovascular surgery. Our goal was to identify the cause of our unusual outbreak of PCS.

Methods

For almost one year after September 2010, cases of PCS increased significantly in our department. We analyzed 973 patients who had received a major craniotomy between January 2009 and November 2011. We included seizures that occurred only in the first 24 postoperative hours, which we defined as early PCS. After verifying the presence of PCS, we analyzed multiple seizure-provoking factors and their relation to the duration and character of seizure activity.

Results

Overall PCS incidence was 7.2% (70/973). Cefazolin (2 g/L saline) was the antibiotic drug used for intraoperative irrigation in 88.4% of the operations, and no PCS occurred without intraoperative cefazolin irrigation. When analyzed by operation type, clipping surgery for unruptured aneurysms was the most frequently associated with PCS (80%). Using logistic regression, only 2 g cefazolin intraoperative irrigation (p=0.024) and unruptured aneurysm clipping surgery (p<0.001) were associated with early PCS. The seizure rate of unruptured aneurysm clipping surgery using 2 g cefazolin intraoperative irrigation was 32.9%.

Conclusion

Intraoperative cefazolin irrigation must be avoided in patients undergoing craniotomy, especially for clipping of unruptured aneurysms, because of the increased risk of early PCS.     

The International SSRI Pharmacogenomics Consortium (ISPC): a genome-wide association study of antidepressant treatment response

Response to treatment with selective serotonin reuptake inhibitors (SSRIs) varies considerably between patients. The International SSRI Pharmacogenomics Consortium (ISPC) was formed with the primary goal of identifying genetic variation that may contribute to response to SSRI treatment of major depressive disorder. A genome-wide association study of 4-week treatment outcomes, measured using the 17-item Hamilton Rating Scale for Depression (HRSD-17), was performed using data from 865 subjects from seven sites. The primary outcomes were percent change in HRSD-17 score and response, defined as at least 50% reduction in HRSD-17. Data from two prior studies, the Pharmacogenomics Research Network Antidepressant Medication Pharmacogenomics Study (PGRN-AMPS) and the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study, were used for replication, and a meta-analysis of the three studies was performed (N=2394). Although many top association signals in the ISPC analysis map to interesting candidate genes, none were significant at the genome-wide level and the associations were not replicated using PGRN-AMPS and STAR*D data. Top association results in the meta-analysis of response included single-nucleotide polymorphisms (SNPs) in the HPRTP4 (hypoxanthine phosphoribosyltransferase pseudogene 4)/VSTM5 (V-set and transmembrane domain containing 5) region, which approached genome-wide significance (P=5.03E−08) and SNPs 5'' upstream of the neuregulin-1 gene, NRG1 (P=1.20E−06). NRG1 is involved in many aspects of brain development, including neuronal maturation and variations in this gene have been shown to be associated with increased risk for mental disorders, particularly schizophrenia. Replication and functional studies of these findings are warranted.     

Delayed hippocampal neuronal death in young gerbil following transient global cerebral ischemia is related to higher and longer-term expression of p63 in the ischemic hippocampus

The tumor suppressor p63 is one of p53 family members and plays a vital role as a regulator of neuronal apoptosis in the development of the nervous system. However, the role of p63 in mature neuronal death has not been addressed yet. In this study, we first compared ischemia-induced effects on p63 expression in the hippocampal regions (CA1–3) between the young and adult gerbils subjected to 5 minutes of transient global cerebral ischemia. Neuronal death in the hippocampal CA1 region of young gerbils was significantly slow compared with that in the adult gerbils after transient global cerebral ischemia. p63 immunoreactivity in the hippocampal CA1 pyramidal neurons in the sham-operated young group was significantly low compared with that in the sham-operated adult group. p63 immunoreactivity was apparently changed in ischemic hippocampal CA1 pyramidal neurons in both ischemia-operated young and adult groups. In the ischemia-operated adult groups, p63 immunoreactivity in the hippocampal CA1 pyramidal neurons was significantly decreased at 4 days post-ischemia; however, p63 immunoreactivity in the ischemia-operated young group was significantly higher than that in the ischemia-operated adult group. At 7 days post-ischemia, p63 immunoreactivity was decreased in the hippocampal CA1 pyramidal neurons in both ischemia-operated young and adult groups. Change patterns of p63 level in the hippocampal CA1 region of adult and young gerbils after ischemic damage were similar to those observed in the immunohistochemical results. These findings indicate that higher and longer-term expression of p63 in the hippocampal CA1 region of the young gerbils after ischemia/reperfusion may be related to more delayed neuronal death compared to that in the adults.     

The Need for a Coagulation Assay after Initiation of New Oral Anticoagulants in Patients with Renal Dysfunction: A Case Report

Background

Dabigatran etexilate, a new oral anticoagulant, was recently approved as an efficacious alternative to warfarin for the prevention of first and recurrent stroke in patients with nonvalvular atrial fibrillation. Limited data are available for dabigatran use in patients with a creatinine clearance rate (CrCL) of 15-30 mL/min. Furthermore, current guidelines do not recommend frequent blood monitoring after dabigatran use. We report herein a patient with severe renal dysfunction who exhibited profound coagulopathy after 2 days of dabigatran use.

Case Report

An 87-year-old woman was admitted for altered mental status and left-side weakness. She was diagnosed with right middle cerebral artery infarction. The baseline assessment revealed a serum creatinine concentration of 1.29 mg/dL and a CrCL of 27.2 mL/min. Dabigatran therapy was started 5 weeks after admission at a dosage of 110 mg twice daily. After 2 days of dabigatran use, the patient developed multiple bruises and evidence of upper-gastrointestinal bleeding. Laboratory tests demonstrated a severe coagulopathy, with a prothrombin time of 85.9 sec, an international normalized ratio of 11.36, an activated partial thromboplastin time of 119.2 sec, and a thrombin time of 230.8 sec. Serial assessment of the patient''s renal function revealed substantial fluctuation of the CrCL (range, 17.9-26.5 mL/min).

Conclusions

The present case emphasizes the need for frequent checking of renal function and assessment using coagulation assays after commencing dabigatran therapy in patients with moderate-to-severe renal impairment.     

Neural indicators of emotion regulation via acceptance vs reappraisal in remitted major depressive disorder

Mood disorders are characterized by impaired emotion regulation abilities, reflected in alterations in frontolimbic brain functioning during regulation. However, little is known about differences in brain function when comparing regulatory strategies. Reappraisal and emotional acceptance are effective in downregulating negative affect, and are components of effective depression psychotherapies. Investigating neural mechanisms of reappraisal vs emotional acceptance in remitted major depressive disorder (rMDD) may yield novel mechanistic insights into depression risk and prevention. Thirty-seven individuals (18 rMDD, 19 controls) were assessed during a functional magnetic resonance imaging task requiring reappraisal, emotional acceptance or no explicit regulation while viewing sad images. Lower negative affect was reported following reappraisal than acceptance, and was lower following acceptance than no explicit regulation. In controls, the acceptance > reappraisal contrast revealed greater activation in left insular cortex and right prefrontal gyrus, and less activation in several other prefrontal regions. Compared with controls, the rMDD group had greater paracingulate and right midfrontal gyrus (BA 8) activation during reappraisal relative to acceptance. Compared with reappraisal, acceptance is associated with activation in regions linked to somatic and emotion awareness, although this activation is associated with less reduction in negative affect. Additionally, a history of MDD moderated these effects.     

Posterior Cerebral Artery Insufficiency in Pediatric Moyamoya Disease

The majority of clinical studies on moyamoya disease (MMD) have focused on anterior circulation. The disease involvement of posterior circulation in MMD, mainly in the posterior cerebral artery (PCA), has been mentioned since the early 1980s, and it has been repeatedly emphasized as one of the most important factors related to poor prognosis in MMD. However, its clinical features and outcome have only been elucidated during the last few years. In this review, the angiographic definition of PCA stenosis is summarized. The clinical features are elucidated as being either early-onset or delayed-onset, according to the time of PCA stenosis diagnosis in reference to the anterior circulation revascularization surgeries. The surgical strategy and hypothesis on the mechanism of PCA stenosis is also briefly mentioned. It appears that some MMD patients may show PCA stenosis during the early or late course of the disease and that the presenting symptoms may vary. Because the hemodynamic compromise caused by PCA stenosis may respond well to surgical treatment, clinicians should be aware of the condition, especially during follow-up of MMD patients.     

Brain Activation Evoked by Sensory Stimulation in Patients with Spinal Cord Injury : Functional Magnetic Resonance Imaging Correlations with Clinical Features

Objective

The purpose of this study is to determine whether the changes of contralateral sensorimotor cortical activation on functional magnetic resonance imaging (fMRI) can predict the neurological outcome among spinal cord injury (SCI) patients when the great toes are stimulated without notice.

Methods

This study enrolled a total of 49 patients with SCI and investigated each patient''s preoperative fMRI, postoperative fMRI, American Spinal Injury Association (ASIA) score, and neuropathic pain occurrence. Patients were classified into 3 groups according to the change of blood oxygenation level dependent (BOLD) response on perioperative fMRI during proprioceptive stimulation with repetitive passive toe movements : 1) patients with a response of contralateral sensorimotor cortical activation in fMRI were categorized; 2) patients with a response in other regions; and 3) patients with no response. Correlation between the result of fMRI and each parameter was analyzed.

Results

In fMRI data, ASIA score was likely to show greater improvement in patients in group A compared to those belonging to group B or C (p<0.001). No statistical significance was observed between the result of fMRI and neuropathic pain (p=0.709). However, increase in neuropathic pain in response to the signal change of the ipsilateral frontal lobe on fMRI was statistically significant (p=0.030).

Conclusion

When there was change of BOLD response at the contralateral sensorimotor cortex on perioperative fMRI after surgery, relief of neurological symptoms was highly likely for traumatic SCI patients. In addition, development of neuropathic pain was likely to occur when there was change of BOLD response at ipsilateral frontal lobe.