Ayca Ozkul

Oxidative stress in acute ischemic stroke

Oxidative stress plays an important role in acute ischemic stroke pathogenesis. Free radical formation and subsequent oxidative damage may be a factor in stroke severity. Serum levels of nitric oxide (NO), malondialdehyde (MDA) and glutathione (GSH) were measured within the first 48 h of stroke in 70 patients. The levels were also correlated with the clinical outcomes using Canadian Neurological Scale (CNS) scores. The results were compared with a control group consisting of 70 volunteers with similar stroke risk factors. Serum NO, MDA and GSH levels were significantly elevated in acute stroke patients. CNS score was negatively correlated with both MDA and NO levels. However, no statistically significant correlation between GSH levels and CNS scores was detected. Our results suggest deleterious effects of oxidative stress on clinical outcome in acute ischemic stroke. The elevation of GSH levels may be an adaptive mechanism during this period.

Sympathetic skin response in idiopathic and diabetic carpal tunnel syndrome

BACKGROUND In carpal tunnel syndrome (CTS), certain changes were expected in sympathetic skin response (SSR) because median nerve carries postganglionic unmyelinated fibres. PURPOSE To investigate the median and ulnar SSR in idiopathic and diabetic CTS without autonomic dysfunction in hands and to find possible relations with electrophysiological features of these diseases. PATIENTS AND METHODS SSRs were elicited by electrical stimulation on the supraorbital nerve and recorded from the median and ulnar territories in the hand from 20 diabetic patients with only CTS (29 hands), 24 idiopathic CTS patients (42 hands) and 13 normal subjects (26 hands). Hands with ulnar neuropathy at the wrist without symptoms and normal hands of unilateral CTS were excluded. In addition to classical parameters and comparative methods, SSR waveform changes and percentile method was used in finding abnormality. RESULTS Median SSRs had significant delayed latency compared to ulnar latency in both CTS patients but this was not important clinically (1.38/1.37 s for idiopatic CTS; 1.43/1.36 s for diabetic CTS). Median and ulnar SSR amplitude, area, median/ulnar latency difference, amplitude and area ratio were compared and only median/ulnar latency difference and median/ulnar latency ratio were found different between the three groups. Four idiopathic CTS hands were outside of the limits or absent (9.5%). SSR waveforms were significantly different from normal subjects in CTS patients. P type SSR replaced M type in idiopathic CTS and N type in diabetic CTS. CONCLUSIONS Findings regarding SSR parameters suggest that unmyelinated C fibers were affected in CTS. These values were not useful because they were too small. Data on SSR were not normally distributed and the percentile method seems to be more convenient for finding any abnormality in clinical practice. Also, SSR waveform analysis could give us valuable data and should add to the SSR examination parameters.

Microscopic polyangiitis presenting with medullary infarct

Microscopic polyangiitis is a small vessel vasculitis which is rarely associated with ischemic stroke. Cerebrovascular disease has rarely been reported in connection with this disease. It may cause fatal hemorrhage, hemorrhagic conversion and multiple lacunar infarcts. We report here a 55-year-old woman with left medullary oblangata infarction without any symptoms of microscopic polyangiitis. During hospitalization, retinal ischemia, mononeuritis multiplex and pulmonary infiltration developed. Sural nerve biopsy was concomitant with small vessel vasculitis. Elevated CRP and sedimentation and positive P-ANCA led to confirmation of a diagnosis of microscopic polyangiitis. Our patient is a rare case of microscopic polyangiitis presenting with medullary infarction. Although the characteristics of this disease are well-known, the first symptom can be a medullary infarction, which has not been reported in literature before.

Carpal tunnel syndrome and ulnar neuropathy at the wrist: comorbid disease or not?

Summary The aim of this study was to elucidate the possible association between carpal tunnel syndrome (CTS) and ulnar neuropathy at the wrist because of the contradictory results of previous studies. Thus, a retrospective case–control study was arranged with an electromyographic database including patients between 2003 and 2009. Patients were selected according to initial diagnosis and the examiners criteria, and data were plotted by computer. One thousand nine hundred twenty-four patients were evaluated for CTS and 1,024 patients for diabetic CTS or diabetic polyneuropathy. CTS and ulnar neuropathy co-occurrence and CTS alone at the wrist was found in 54/404, 19/50, 20/27 patients, respectively. Logistic regression analysis revealed that having CTS was associated with a doubled risk of ulnar neuropathy at the wrist in both idiopathic CTS and diabetic CTS groups but not in diabetic polyneuropathy. Being male and of advanced age were other risk factors for ulnar neuropathy at the wrist. Correlation analysis (age and sex were controlled) revealed decreased but significant correlations between median and ulnar sensory amplitudes in CTS cases in all groups.

Natural course and treatment efficacy: one-year observation in diabetic and idiopathic carpal tunnel syndrome.

Our aims were to observe the effects of rehabilitation and surgery on idiopathic and diabetic carpal tunnel syndrome (CTS) and compare them with the natural course of the disease. Forty-two patients aged 33 to 74 years with clinically diagnosed, electrophysiologically confirmed, and laboratory screened hands with CTS (46 idiopathic and 34 diabetic) were enrolled in the study. Improvement of symptom severity and functional status after treatment using the Boston questionnaire (scales), changes of nerve conduction parameters (NCPs), and correlations between NCP and Boston questionnaires were outcome measures. Follow-up periods were 3 to 5 months and 6 to 12 months. In idiopathic CTS, surgery was effective according to scales and NCP. Rehabilitation was also effective according to scales but only in the late period. Nontreatment did not improve scales at a later period. In diabetic CTS, rehabilitation was not effective according to scales. Baseline and follow-up correlations between scales and NCP were weak and limited to sensory amplitudes (baseline), sensory amplitudes-velocity, and median motor distal latency (follow-up). Regression analysis also did not reveal any associations between scales and NCP. A repeated nerve conduction study was not meaningful if the diagnosis was definite. Treatment of CTS was definitely superior to spontaneous improvements. Rehabilitation was ineffective in diabetic CTS.

The Relationship between Protein C, Protein S and Cytokines in Acute Ischemic Stroke

Objective: The role of inflammation in the pathogenesis of acute ischemic stroke is well known, but its association with the clinical picture is as yet unclear. Material and Methods: In our study, we measured the serum levels of the proinflammatory cytokines interleukin-1β (IL-1β), tumor necrosis factor α (TNFα) and interleukin-6 (IL-6) within the first 50 h of stroke in 60 acute stroke patients, and examined the association with the natural anticoagulants protein C and free protein S. We compared the results with a control group that consisted of 30 volunteers. We also correlated their levels with the clinical outcomes by using the Canadian Neurological Scale (CNS). Results: Neither stroke patients nor the control group had any elevations in IL-1β serum levels. However, the levels of serum IL-6 were significantly higher in stroke patients (13.7 ± 19.46 vs. 4.3 ± 15.88, p = 0.002). In addition, the protein S levels of patients were lower than those of the controls (84.36 ± 27.97 vs. 95.9 ± 25.64, p = 0.007). Although IL-6 showed negative correlation with protein S (r = –0.504, p = 0.000), the other studied cytokines TNFα and IL-1β did not correlate with these natural anticoagulants. Another negative correlation was found between IL-6 and CNS scores (r = –0.451, p = 0.000). In addition, both protein C and protein S positively correlated with CNS (r = 0.263, p = 0.042; r = 0.381, p = 0.003). There was also a positive correlation between protein C and protein S (r = 0.408, p = 0.001). Conclusions: Our results suggest that TNFα and IL1β serum levels are not elevated in the acute phase of stroke and have no correlation with the natural anticoagulants protein C and protein S. However, a decrease in free protein S may be related to elevated IL-6 levels. In addition, increased levels of IL-6 and reduced levels of protein C and protein S may play a role in acute ischemic stroke severity.

Hereditary Thrombophilic Factors in Stroke Due to Cerebral Infarct

Background:The stroke is the third most common cause of all deaths. In new studies, the importance of hereditary thrombophilic factors on stroke is emphasized. The aim of this study is to determine the role of hereditary thrombophilic factors including factor V Leiden A1691G (FVL), prothrombin G20210A, and methylenetetrahydrofolate reductase (MTHFR) C677T gene mutations in patients with stroke because of cerebral infarct. Methods:Twenty-four patients with stroke and 53 controls with risk factor for stroke were enrolled. Polymerase chain reaction was used to detect these mutations. Results:Heterozygote FVL mutation in 2 (8.3%) patients and MTHFR mutation in 10 (41.7%) patients were detected. In the control group, there were 2 (3.8%) patients with heterozygote FVL mutation and 15 (28.3%) patients with MTHR mutation. Both FVL and MTHFR gene mutations were detected in 1 patient and 2 controls, respectively. Prothrombin gene mutation was not found in 2 groups. There were not statistically significant differences for all 3 mutations in-between 2 groups (P > 0.05). Odds ratios were 0.431 (0.074–2.504, 95% CI) for FVL mutation and 0.553 (0.221–1.381, 95% CI) for MTHFR mutation, respectively. Conclusion:Although our study group was small, hereditary thrombophilic factors might not be risk factors for stroke because of cerebral infarct.

Proximal femoral conductions in patients with lumbosacral radiculoplexus neuropathy

OBJECTIVES Lumbosacral radiculoplexus neuropathy (DLRPN) is a rare form of neuropathy observed in diabetic and rarely non-diabetic patients. Pathophysiology and lesion location are not clearly understood. Our aim was to analyze proximal and distal femoral conductions in patients with DLRPN. METHODS Six patients with DLRPN, 14 patients with diabetic polyneuropathy and 25 healthy subjects were included in the study. We performed L3 monopolar root stimulation and femoral nerve trunk stimulation at the inguinal region and calculated lumbar plexus conduction time by subtracting the latency of compound muscle action potential (CMAP) of the vastus medialis evoked by femoral nerve stimulation from the latency of CMAP of vastus medialis evoked by L3 root stimulation. Additionally peak to peak amplitudes and areas of CMAPs were analyzed. RESULTS Electrophysiological examination showed that there was an axonal involvement in all patients with DLRPN. Prolonged lumbar plexus conduction time (in five extremities), and prolonged distal latency of the femoral nerve (in five extremities) probably due to secondary demyelination were also observed. Similar abnormalities were not observed in the diabetic polyneuropathy group. CONCLUSIONS DLRPN may affect different localizations on the peripheral nerves. L3 root stimulation may have an important role in the electrodiagnosis of DLRPN.

The relationship between insulin resistance and hypercoagulability in acute ischemic stroke.

Aim: Insulin resistance has effects on the coagulation system, which is important in the acute phase of infarct. We examined the relationships between insulin resistance, hemostatic markers and stroke severity in acute ischemic stroke patients. Methods: Protein C (PC), protein S (PS), fibrinogen, von Willebrand factor and antithrombin III (AT III) were studied in 75 acute ischemic stroke patients with and without insulin resistance. Results: The PC and PS levels of insulin-resistant patients were significantly lower than those of non-insulin-resistant patients (PC: 87 ± 19.23 vs. 97.89 ± 13.3%, p = 0.007; PS: 84.75 ± 15.72 vs. 93.21 ± 15.02%, p = 0.02), and both of the anticoagulants were correlated with the homeostasis model assessment (HOMA; r = –0.339, p = 0.003 and r = –0.481, p = 0.000, respectively). Additionally, the NIH Stroke Scale (NIHSS) score correlated negatively with PS (r = –0.329, p = 0.004) and AT III levels (r = –0.235, p = 0.04). The parameters with positive correlations with NIHSS were fibrinogen (r = 0.270, p = 0.019), fasting glucose (r = 0.358, p = 0.008) and HOMA (r = 0.286, p = 0.013). Conclusions: The significant associations between insulin resistance and hemostatic markers may be relevant to stroke severity by causing a procoagulant tendency in acute ischemic stroke.

Morphological Assessment of Cadaveric Radial, Brachial and Subclavian Arteries: A Neurointerventional Approach.

Objective The transradial catheterization (TRC) is becoming widespread, primarily for neurointerventions. Therefore, the evaluation of radial artery puncture in clinical practice and a better understanding of the anatomy are important to improve the safety of neuroendovascular surgery. Methods Ten formalin-fixed adult Korean cadavers were dissected to expose radial artery (RA), brachial artery (BrA) and subclvian artery (ScA), bilaterally. Vessel lengths and diameters were meaured using a caliper and distance between the specific point of vessels and the anatomical landmarks including the radial styloid process, the medial epicondyle of the humerus, the sternoclavicular joint, and the vertebral artery orifice were also measured. Results The average length between the radial (RAPS) and the BrA puncture sites (BrAPS) and between the vertebral artery orifice (VAO) and the BrA bifurcation (BrAB) did not differ between sides (p>0.05). The average length between the radial styloid process (RSP) and the RAPS was 13.41±2.19 mm, and the RSP was 26.85±2.47 mm from the median nerve (MN). The mean length between the medial epicondyle (ME) and the BrAPS as 44.23±5.47 mm, whereas the distance between the ME and the MN was 42.23±4.77 mm. The average VAO-ScA angle was 70.94±6.12°, and the length between the ScA junction (SCJ) and the VAO was 60.30±8.48 mm. Conclusion This study provides basic anatomical information about the radial artery and the brachial route and can help improving new techniques, selection of size and shape of catheters for TRC. This can help neurointerventionists who adopt a transradial neuroendovascular approach and offers comprehensive and safe care to their patients.