Tzu-Ming Yang

The value of serial plasma nuclear and mitochondrial DNA levels in patients with acute ischemic stroke

BACKGROUND Elevated circulating cell-free DNA in plasma is reported in several critical diseases. This study hypothesized that since plasma nuclear and mitochondrial DNA substantially increase after acute ischemic stroke and decrease thereafter, their levels can predict treatment outcomes. METHODS Plasma nuclear and mitochondrial DNA levels were serially examined in 50 acute ischemic stroke patients and in 50 at risk control subjects during the study period. RESULTS Levels of plasma nuclear and mitochondrial DNA in patients with acute ischemic stroke were significantly higher than those in the controls (p<0.05). Elevated circulating nuclear DNA in plasma persisted until one month after the acute stroke. Levels of plasma nuclear DNA positively correlated to the clinical severity of stroke as reflected by the National Institutes of Health Stroke Scale. CONCLUSION Levels of plasma nuclear and mitochondrial DNA reflect the severity of cerebral damage after acute cerebral infarction. Assay of plasma DNA levels can be considered a neuro-pathologic marker of patients with acute ischemic stroke.

Factors predictive of outcome in posttraumatic seizures.

BACKGROUND Seizures are important neurologic complications of traumatic brain injury (TBI). There is a need for better delineation of potential prognostic factors and outcomes in patients with posttraumatic seizures (PTS) who could receive treatment when brought to the hospital. METHODS In this 10-year retrospective study, 170 adult patients with PTS were enrolled in this study. The degree of seizure control was analyzed using a Seizure Frequency Scoring System, which classified them into excellent and nonexcellent outcomes. RESULTS There were 170 patients with acute symptomatic seizure enrolled in this study, 106 of whom had early PTS, whereas 64 had late PTS. Of the 106 early PTS, 58% (61 of 106) occurred within 24 hours of trauma. Risk factors for developing nonexcellent outcome included patients who undergo surgical intervention and presence of late-provoked seizures during the acute phase of TBI. CONCLUSIONS Seizures are an important neurologic complication of TBI. Regarding the potentially side effects of antiepileptic drugs, antiepileptic therapy should be carefully administrated in those nonexcellent outcome patients.

Predictors and outcome of seizures after spontaneous intracerebral hemorrhage. Clinical article.

OBJECT Seizures are an important neurological complication of spontaneous intracerebral hemorrhage (ICH). A better understanding of the risk factors of seizures following ICH is needed to predict which patients will require treatment. METHODS Two hundred and forty-three adult patients were enrolled in this 1-year retrospective study. Multiple logistic regression was used to evaluate the relationship between baseline clinical factors and the presence or absence of seizure during the study period. RESULTS Seizures occurred in 20 patients with ICH, including acute symptomatic seizures in 9 and unprovoked seizures in 11. None progressed to status epilepticus during hospitalization. After a minimum 3-year follow-up period, the mean Glasgow Outcome Scale score was 3.8+/-1.1 for patients who had had seizures and 3.5+/-1.3 for those who had not. The multiple logistic regression model demonstrated that the mean ICH volume was independently associated with seizures, and any increase of 1 mm3 in ICH volume increased the seizure rate by 2.7%. CONCLUSIONS Higher mean ICH volumes at presentation were predictive of seizure, and the presence of late seizures was predictive of developing epilepsy. Most seizures occurred within 2 years of spontaneous ICH over a minimum of 3 years of follow-up.

Predictors and outcomes of shunt-dependent hydrocephalus in patients with aneurysmal sub-arachnoid hemorrhage

BackgroundHydrocephalus following spontaneous aneurysmal sub-arachnoid hemorrhage (SAH) is often associated with unfavorable outcome. This study aimed to determine the potential risk factors and outcomes of shunt-dependent hydrocephalus in aneurysmal SAH patients but without hydrocephalus upon arrival at the hospital.MethodsOne hundred and sixty-eight aneurysmal SAH patients were evaluated. Using functional scores, those without hydrocephalus upon arrival at the hospital were compared to those already with hydrocephalus on admission, those who developed it during hospitalization, and those who did not develop it throughout their hospital stay. The Glasgow Coma Score, modified Fisher SAH grade, and World Federation of Neurosurgical Societies grade were determined at the emergency room. Therapeutic outcomes immediately after discharge and 18 months after were assessed using the Glasgow Outcome Score.ResultsHydrocephalus accounted for 61.9% (104/168) of all episodes, including 82 with initial hydrocephalus on admission and 22 with subsequent hydrocephalus. Both the presence of intra-ventricular hemorrhage on admission and post-operative intra-cerebral hemorrhage were independently associated with shunt-dependent hydrocephalus in patients without hydrocephalus on admission. After a minimum 1.5 years of follow-up, the mean Glasgow outcome score was 3.33 ± 1.40 for patients with shunt-dependent hydrocephalus and 4.21 ± 1.19 for those without.ConclusionsThe presence of intra-ventricular hemorrhage, lower mean Glasgow Coma Scale score, and higher mean scores of the modified Fisher SAH and World Federation of Neurosurgical grading on admission imply risk of shunt-dependent hydrocephalus in patients without initial hydrocephalus. These patients have worse short- and long-term outcomes and longer hospitalization.

Acute autologous bone flap infection after cranioplasty for postinjury decompressive craniectomy

BACKGROUND Acute bone flap infection is a devastating complication after cranioplasty for postinjury decompressive craniectomy. We aim to identify the risk factors of autologous bone flap infection. METHODS We enrolled 151 patients undergoing 153 cranioplasties in the 4-year retrospective study. Autologous bones stored at -75°C were used in the cranioplasties. Acute bone flap infection was defined as the onset of infection ≤14 days after cranioplasty. The epidemiological data of patients and details of the cranioplasty procedure were recorded. RESULTS Acute bone flap infection was identified in five of the 153 cranioplasties, accounting for 3.3% of all episodes. Three of the 5 infected patients and five of 143 uninfected patients presented with dysfunction of subgaleal drainage comparatively, which was significantly different (p=0.001). Statistical analysis of the cranioplasty procedures and subsequent results of the two patient groups revealed the following significant findings: the duration of operation (p=0.03) and the length of hospital stay after cranioplasty (p<0.001). CONCLUSIONS Dysfunction of subgaleal drainage and long operative duration of cranioplasty are risk factors of acute autologous bone flap infection. Regarding the prolonged hospital stay in complicated patients, better surgical techniques should be implemented in order to eliminate the risks of infection.

Computer-assisted pedicle screw placement for thoracolumbar spine fracture with separate spinal reference clamp placement and registration

BACKGROUND The objective of the study was to improve the accuracy of computer-assisted pedicle screw installation in the spine. This study evaluates the accuracy of computer-assisted pedicle screw placement with separate spinal reference clamp placement and registration on each instrumented vertebra for thoracolumbar spine fractures. METHODS Postoperative radiographs and CT scans assessed the accuracy of pedicle screw placement in 21 adult patients on each instrumented vertebra. Screw placements were graded as good if the screws were placed in the central core of the pedicle and the cancellous portion of the body. Screw placements were graded as fair if the screws were placed slightly eccentrically, causing erosion of the pedicular cortex, and with less than a 2-mm perforation of the pedicular cortex. Screw placements were graded as poor if screws were placed eccentrically with a large portion of the screw extending outside the cortical margin of the pedicle and with more than a 2-mm perforation of the pedicular cortex. RESULTS A total of 140 image-guided pedicle screws were placed in 21 patients: 78 in the thoracic and 62 in the lumbar spine. Of the 140 pedicle screw placements, 96.4% (135/140) were categorized as good; 3.6% (5/140), fair; and 0% were poor. All 5 fair placement screws were placed in the thoracic spine without any mobility. CONCLUSION Separate registration increases accuracy of screw placement in thoracolumbar pedicle instrumentation. Separate spinal reference clamp placement in the instrumented vertebra provides real-time virtual imaging that decreases the possibility of downward displacement during manual installation of the screw.

The value of serial plasma and cerebrospinal fluid nuclear and mitochondrial deoxyribonucleic acid levels in aneurysmal subarachnoid hemorrhage.

OBJECT Increased plasma nuclear and mitochondrial DNA levels have been reported in critically ill patients, and extracellular DNA may originate from damaged tissues having undergone necrosis. This study tested the hypothesis that nuclear and mitochondrial DNA levels in CSF and plasma are substantially increased in patients with acute spontaneous aneurysmal subarachnoid hemorrhage (SAH) and decrease thereafter, such that nuclear and mitochondrial DNA levels may be predictive of treatment outcomes. METHODS Serial nuclear and mitochondrial DNA levels in CSF and plasma from 21 adult patients with spontaneous aneurysmal SAH and 39 healthy volunteers who received myelography examinations during the study period were evaluated. RESULTS Data showed that circulating plasma nuclear DNA concentrations and both nuclear and mitochondrial DNA levels in CSF significantly increased in patients with aneurysmal SAH on admission compared with the volunteers. In patients with poor outcome, the CSF nuclear and mitochondrial DNA levels were significantly higher on Days 1 and 4, and plasma nuclear DNA levels were significantly higher from Day 8 to Day 14. Higher CSF nuclear (> 85.1 ng/ml) and mitochondrial DNA levels (> 31.4 ng/ml) on presentation were associated with worse outcome in patients with aneurysmal SAH. CONCLUSIONS Higher CSF DNA levels on presentation, rather than plasma DNA levels, are associated with worse outcomes in patients with acute spontaneous aneurysmal SAH. More prospective multicenter investigations are needed to confirm the predictive value of CSF and plasma DNA levels on outcome.

Clinical characteristics of post-neurosurgical Klebsiella pneumoniae meningitis in adults and a clinical comparison to the spontaneous form in a Taiwanese population

A total of 46 patients (nine post-neurosurgical, 37 spontaneous) with adult bacterial meningitis (ABM) caused by Klebsiellapneumoniae infection were included in this study. The nine patients in the post-neurosurgical K. pneumoniae ABM group (seven male, two female) had a mean age of 48.9 years. Two patients in this group also had diabetes mellitus (DM) and one had liver disease. The most common presentation of patients in post-neurosurgical K. pneumoniae ABM group was fever (nine patients), followed by altered consciousness (seven patients) and hydrocephalus (six patients). With medical and/or surgical treatment, a mortality of 22.2% (2/9) occurred. Compared to patients who had spontaneous K. pneumoniae ABM, those with the post-neurosurgical form had a lower incidence of community-acquired infection, seizure and DM, but had a higher incidence of leukocytosis, hydrocephalus, cerebrospinal fluid leak and bacterial strains with extended-spectrum beta-lactamase. Univariate analysis found these clinical differences to be statistically significant, however they were not significant on multivariate analysis. This study reveals that there are clinical differences between the post-neurosurgical and spontaneous presentations of K. pneumoniae ABM.

Statin pre-treatment is associated with lower platelet activity and favorable outcome in patients with acute non-cardio-embolic ischemic stroke

IntroductionStatins reportedly have anti-inflammatory and anti-thrombotic effects aside from cholesterol-lowering. This study aimed to evaluate the effect of pre-existing statin use on platelet activation markers and clinical outcome in acute ischemic stroke patients.MethodsThis prospective study evaluated 172 patients with acute ischemic stroke divided in two groups: patients with pre-existing statin (n = 43) and without pre-existing statin (66 cases with statins initiated post-stroke and 63 without statin treatment). Platelet activation markers (CD62P and CD63) were measured by flow cytometry at different time points after stroke and analyzed with clinical outcome.ResultsThe CD62P and CD63 expressions on platelets were significantly lower in the patients with pre-existing statin use compared to the patients without pre-existing statin use on Day 1 post-stroke (p < 0.05). The CD62P expression was significantly lower in the patients with pre-existing statin use on 90 days after the acute stroke (p < 0.05). Patients with pre-existing statin use had lower incidences of early neurologic deterioration (END) than those without treatment (p < 0.05). Among several baseline clinical variables, admission NIHSS score, history of coronary artery disease, and pre-existing statin use were independent predictions of good clinical outcome at three months.ConclusionsPre-existing statin use is associated with decreased platelet activity as well as improved clinical outcome and reduced END in patients with acute ischemic stroke.

The Association Between Symptomatic Delayed Cerebral Infarction and Serum Adhesion Molecules in Aneurysmal Subarachnoid Hemorrhage

BACKGROUND:Serum concentrations of adhesion molecules may be connected to the pathogenesis of delayed cerebral infarction (DCI) after aneurysmal subarachnoid hemorrhage (SAH). OBJECTIVE:To test the hypothesis that levels of adhesion molecules are substantially increased after DCI and decreased thereafter and that these levels can predict treatment outcomes. METHODS:Serial circulating markers of adhesion molecules were examined in 21 consecutive SAH patients and 2 risk control subjects. All underwent cerebral angiography and magnetic resonance imaging to confirm the DCI. The timing of magnetic resonance imaging was fixed in the acute phase and before hospital discharge. RESULTS:Symptomatic DCI developed in 33% of the patients (7 of 21). Statistical analysis of levels of adhesion molecules between patients with and those without DCI revealed that soluble (s) L-selectin, sP-selectin, and sE-selectin concentrations significantly increased after symptomatic DCI (P = .003, .013, and .043, respectively). Only higher sL-selectin level on presentation (cutoff value > 636 ng/mL) was significantly associated with poor outcome after 6 months of follow-up. CONCLUSION:Increased sL-selectin, sP-selectin, and sE-selectin levels imply risks of symptomatic DCI after aneurysmal SAH. The high frequency of symptomatic DCI and higher sL-selectin level on presentation may be associated with worse outcomes.