The relationship of median nerve F-wave parameters with severity and subtypes of carpal tunnel syndrome.

PURPOSE: F-wave analysis may help affirm or disprove a compression neuropathy. In this study we have analysed the effects of focal median nerve injury on F wave in Carpal Tunnel Syndrome (CTS). METHOD: We studied 57 patients (100 hands) with clinical and electrophysiological CTS and 31 (62 hands) healthy subjects. Median nerve F-waves were evaluated following 10 supramaximal stimuli and recording from abductor pollicis brevis muscles. Minimum, maximum, and mean F-wave latencies, frequency of the F wave (Fp), chronodispersion (F_{CD}), mean F/M amplitude ratios (mF/M-amp) and F-wave conduction velocity (FwCV) were evaluated. RESULTS: The CTS patients showed prolonged F-wave latencies, decreased Fp, and an increase of the F_{CD} as compared with normative values. Absent F wave was presented in 8 of 34 hands (23.5%) with severe CTS patients. In the severe group, the FwCV was significantly slower (p< 0.001) and the mF/M-amp was significantly higher (p< 0.001) than that of mild and moderate groups, respectively. Also, the mF/M-amp was significantly greater and Fp was lower in the axonal type than in the demyelinating type. The F_{CD} was not different among groups. A strong positive correlations between mMDL with Fmin (r=0.81, p< 0.000), Fmean (r=0.80, p< 0.000) and Fmax (r=0.71, p< 0.000) were revealed. CONCLUSION: Results support the differing effects of demyelinating and axonal injury on F-waves and suggest that the mF/M-amp ratio and FwCV, which is influenced by neuronal damages in the distal segment of the median nerve, is useful in the discrimination of CTS severity.

Rapid eye movement dependent central apnea with periodic leg movements.

Central sleep apnea is a period of at least 10 s without airflow, during which no ventilatory effort is present. Most of the central apneas occur in Non-Rapid eye movement (NREM) sleep. Central apnea occuring in Rapid eye movement (REM) sleep is extremely rare. We present our patient who had a diagnosis of obstructive sleep apnea in another sleep center since 2003. His Auto Continuous Positive Airway Pressure (CPAP) machine was disrupted so he admitted to our center to renew his machine and for daytime sleepiness while using his machine. The polysomnography revealed central apneas ending with respiratory arousals and periodic leg movements in rapid eye movement (REM) stage. We found no cause for central apneas. The patient benefited from servo ventilator therapy. We present this case as an unusual form of central apnea with the review of the literatures. Even the patients diagnosed as obstructive sleep apnea should be analyzed carefully. The diagnosis and the therapeutic approach may change in the favor of the patient.

Paraoxonase 1 gene polymorphisms, paraoxonase/arylesterase activities and oxidized low-density lipoprotein levels in patients with migraine.

The vascular endothelial dysfunction has been implicated in the pathogenesis of migraine. Oxidized low-density lipoprotein (ox-LDL) may impair endothelial function. Paraoxonase-1 (PON-1) prevents oxidative modification of LDL cholesterol (LDL-C). So we investigated serum PON-1 and arylesterase (ARE) activities, PON-1 55 L/M and 192Q/R polymorphisms and the serum lipid profile in patients with migraine. Biochemical parameters and PON-1 polymorphism analyses were assessed in 104 patients with migraine and 86 healthy subjects. Ox-LDL was detected by ELISA, and polymorphisms were determined using PCR-restriction fragment length polymorphism analysis. Patients with migraine had lower PON-1 and ARE activities (p < 0·001, for both) and higher ox-LDL and LDL-C levels (p < 0·001, for both) and ox-LDL: LDL-C ratio (p < 0·005) than the controls. The genotype distribution and the allele frequencies for PON-1 55 L/M and 192Q/R polymorphisms were not different among the study populations. The results of our current study indicate that migrainous patients have decreased serum PON-1 and ARE activities and increased serum ox-LDL levels, which may have a clinical importance in the treatment of migraine.

Prognostic values of lesion volume and biochemical markers in ischemic and hemorrhagic stroke: a stereological and clinical study.

PURPOSE: Our aim was to evaluate the relationship between lesion volume, serum level of biochemical markers, and clinical situation in ischemic and hemorrhagic stroke. METHODS: MRI was obtained on 33 ischemic and 28 hemorrhagic strokes. The Cavalieri method was used to measure the volume. To evaluate neurological situation of the patients, we used the National Institutes of Health Stroke Scale (NIHSS) and Rankin Disability Scores at the first, third, seventh, and thirtieth days. We measured the level of leptin, high sensitivity C-reactive protein (hs-CRP), insulin, cortisol, fibrinogen, protein C, protein S, von Willebrand factor, D-dimer, Antitrombin III, and Factor VIII (F VIII) at the same time intervals. RESULTS: In ischemic events, cortisol level at third and seventh days, and fibrinogen level at the first day were correlated with lesion volumes (r = 0.5, p = .02; r = 0.4, p = .02; r = 0.5, p = .005, respectively). In hemorrhagic events, only fibrinogen level was correlated with lesion volumes at third day (r = 0.6, p = .04). No significant differences were found among all these biochemical parameters, neurological situation (p > .05), and lesion volumes at all times. CONCLUSION: In the prediction of stroke prognosis, lesion volume and all of the evaluated biochemical parameters are not deterministic factors.

Sensitivities of conventional and new electrophysiological techniques in carpal tunnel syndrome and their relationship to body mass index.

The purpose of this study is to evaluate prospectively the sensitivities of conventional and new electrophysiological techniques and to investigate their relationship with the body mass index (BMI) in a population of patients suspected of having carpal tunnel syndrome (CTS). In this study, 165 hands of 92 consecutive patients (81 female, 11 male) with clinical diagnosis of CTS were compared to reference population of 60 hands of 30 healthy subjects (26 female and 4 male). Extensive sensory and motor nerve conduction studies (NCSs) were performed in the diagnosis of subtle CTS patients. Also, the patients were divided into subgroups and sensitivities were determined according to BMI. The mean BMI was found to be significantly higher in the CTS than in the control group (p < 0.001). The sensitivity of the median sensory nerve latency (mSDL) and median motor distal latency (mMDL) were 75.8% and 68.5%, respectively. The most sensitive parameters of sensory and motor NCSs were the difference between median and ulnar sensory distal latencies to the fourth digit [(D4M-D4U), (77%)] and the median motor terminal latency index [(mTLI), (70.3%)], while the median-to-ulnar sensory action potential amplitude ratio (27%) and the median-thenar to ulnar-hypothenar motor action potential amplitude ratio (15%) were least sensitive tests. Sensory tests were more sensitive than motor NCSs. Combining mSDL with D4M-D4U, and mMDL with mTLI allowed for the detection of abnormalities in 150 (91%) and 132 (80%) hands, respectively. Measurements of all NCSs parameters were abnormal in obese than in non-obese patients when compared to the BMI. The newer nerve conduction techniques and combining different NCSs tests are more sensitive than single conventional NCS test for the diagnosis of suspected CTS. Meanwhile, CTS is associated with increasing BMI.