OPTIC NERVE SHEATH SONOGRAPHY IS A PROMISING TOOL FOR ASSESSMENT OF RAISED INTRACRANIAL PRESSURE IN PATIENTS ADMITTED TO NEUROLOGICAL INTENSIVE CARE UNIT.

Optic nerve sheath diameter (ONSD) enlargement is detectable in traumatic brain injury patients with raised intracranial pressure (ICP). The aim was to assess its value in neurological patients suspected to have increased ICP. Patient clinical imaging data and hospitalization outcome were analyzed. Patients were divided into groups according to brain pathology and level of consciousness with Glasgow Coma Score (GCS). Poor hospitalization outcome was assessed by modified Rankin scale (mRS) >3. Data obtained by ocular sonography performed in acute setting were compared with data of 100 control subjects. Data were expressed as mean ± SD. Intergroup comparison was performed by Student's t-test. Data of 34 patients (63+16 years) were suitable for analysis, including 8 primary intracerebral hemorrhage (PICH), 8 subarachnoid hemorrhage (SAH), 12 PICH or SAH and intraventricular hemorrhage (IVH), 4 tumors and 2 ischemic strokes. The mean ONSD was 5.86+0.69 mm in patients versus 4.38+0.41 mm in controls (p<0.01). ONSD was 6.28+0.61 mm in patients with GCS <8 and 5.77+0.55 mm in other patients (p<0.05). ONSD was 5.72+0.59 mm in PICH versus 6.20+0.65 mm in PICH/SAH with IVH (p=0.1). ONSD was 5.73+0.38 mm in SAH in comparison to PICH/SAH with IVH (p=0.05). There was no statistically significant difference in optic nerve diameter between patients and controls (2.48+0.28 mm vs. 2.39+0.33 mm; p>0.05). Pronounced enlargement of ONSD was observed in patients with ICH or SAH with IVH, and in patients with GCS <8. Enlarged ONSD was associated with poor neurological outcome (mRS >3).

Revisiting the Epworth sleepiness scale : Is excessive daytime sleepiness still a valid screening tool for obstructive sleep apnea in a population at risk?

OBJECTIVE: Obstructive sleep apnea (OSA) is a common medical problem with numerous comorbidities and high costs. Since the introduction of the Epworth sleepiness scale (ESS), excessive daytime sleepiness (EDS) has been considered the most common and prominent symptom of OSA. Aim of this study was to re-evaluate the ESS for detection of OSA in a population at risk compared to the gold standard overnight polysomnography (PSG). METHODS: A total of 266 patients (mean age 57.9 ± 11.6 years; 189 men and 77 women), referred to our sleep laboratory for probable OSA, were given ESS followed by an overnight PSG. The ESS values were compared to PSG apnea hypopnea index (AHI) with sensitivity (SE), specificity (SP), positive predictive value (PPV), negative predictive value (NPV) and diagnostic accuracy (DA) calculated for ESS. The positive cut-off value for ESS was ≥ 10 and for AHI ≥ 5. RESULTS: Only 92 (34.6%) subjects had a positive ESS. An OSA was diagnosed by PSG in 213 (80.1%) subjects: 46 having mild, 37 moderate and 130 severe apnea. Most subjects with positive ESS (88.0%) were found to have OSA but most subjects with a negative ESS (75.9%) were also positive for OSA (42% with AHI ≥ 30). The area under the receiver operating characteristic (ROC) curve for ESS was 0.60 (95% confidence interval, CI 0.54-0.66; p = 0.020) with SE 38.0%, SP 79.3%, PPV 88.0%, NPV 24.1% and DA 46.2%. CONCLUSION: It was found that excessive daytime sleepiness, measured by ESS, is not a valuable screening tool for OSA, especially when the test is negative. Other screening tests that involve additional parameters, beside daytime sleepiness alone, should be considered.

The characterization of blood flow changes in mouse tumor during Photofrin-based photodynamic therapy by using the color Doppler ultrasonography.

Changes in blood flow velocity through the tumors can induce damage of tumor microcirculation and thus may contribute to the final destruction of tumor masses after photodynamic therapy (PDT). The aim of this study was to evaluate the blood flow changes in a SCCVII mouse carcinoma during Photofrin-based photodynamic therapy by analyzing several quantitative spectral Doppler parameters [maximum systolic flow velocity (Vmax), end diastolic velocity (Vmin), resistance index (RI) and pulsatile index (PI)] by using the color Doppler ultrasonography. Blood flow velocities were recorded immediately prior to tumor illumination (0 h) and then 2 and 24 h after the illumination. Statistically significant increase in diastolic blood velocity (Vmin) with a corresponding decline in RI and PI was recorded in tumors of the Photofrin-injected mice prior to tumor illumination. However, 2 h after the illumination a pronounced decrease in both Vmin and Vmax was obtained. There were no changes of these parameters in controls at different times during determination. The observed changes of spectral Doppler parameters in tumors from the PDT group point to the transition of tumor blood vessels from the relaxation state recorded before tumor illumination into a state of increased contraction after the activation of Photofrin by light. Pronounced changes in tumor blood vessel tone might be an additional stress for such vessels leading to their ultimate destruction.

Visual evoked response in patients with severe carotid disease--functional transcranial doppler study of posterior circulation.

The goal of this study was to evaluate the visual evoked response in posterior cerebral artery (PCA) by means of functional transcranial doppler in patients with severe carotid disease and to determine the hemodynamic effect of severe carotid disease on posterior circulation. Measurements were performed successively in the dark and during the white light stimulation in 49 patients with high-grade (70-99%) internal carotid artery (ICA) stenosis or occlusion and compared with 30 healthy age and sex matched subjects. Mean blood flow velocities (MBFV) (cm/s +/- 2SD) and mean reaction time (MRT) (s +/- 2SD) during three consecutive repetitive periods of 1 minute each were analyzed. MBFV in PCA during the white light stimulation and in the dark between the two groups didn't differ. MRT in patients showed a significantly prolonged visual evoked response in both affected (light: patients 29.36 +/- 14.46, controls 19.67 +/- 11.25, respectively, p < 0.046; dark: patients 35.25 +/- 11.9 controls 21.89 +/- 10.31, respectively, p < 0.002 and unaffected side (dark: patients 33.13 +/- 11.12, controls 23.89 +/- 11.23, respectively, p < 0.032) of ICA. This data showed that MRT is the principal restrictive factor in the case of carotid stenosis suggesting the independence of cerebral vascular reserve capacity of the posterior part of Willis circle that is necessary to be considered separately.

Bilateral Vertebral Artery Dissection - Multiple Artery Affection or Early Recurrence?

In a certain percentage of patients with craniocervical artery dissection, dissections affect multiple arteries. Some investigators consider that the dissections diagnosed as multiple might have occurred sequentially within a short time frame. We describe an oligosymptomatic patient with bilateral progressive vertebral artery dissection. Careful history taking added new data on transient left arm weakens two months earlier, as a possibility of the earlier disease onset.

Hemispheric asymmetry of visual cortical response by means of functional transcranial Doppler.

We assessed the visual evoked response and investigated side-to-side differences in mean blood flow velocities (MBFVs) by means of functional transcranial Doppler (fTCD) in 49 right-handed patients with severe internal carotid artery (ICA) stenosis and 30 healthy volunteers, simultaneously in both posterior cerebral arteries (PCAs) using 2 MHz probes, successively in the dark and during the white light stimulation. Statistically significant correlation (P = 0.001) was shown in healthy and in patients (P < 0.05) between MBFV in right PCA in physiological conditions and MBFV in right PCA during the white light stimulation and in the dark. The correlation between MBVF in right PCA and contralateral left PCA was not statistically significant (P > 0.05). The correlation between ipsilateral left PCA was significantly higher than the one with contralateral right PCA (P < 0.05). There is a clear trend towards the lateralisation of the visual evoked response in the right PCA.

Cerebrovascular evoked response to repetitive visual stimulation in severe carotid disease--functional transcranial Doppler study.

Hemodynamic features of the posterior circulation were evaluated by assessing visual evoked response in posterior cerebral artery (PCA) by means of functional transcranial Doppler (fTCD) in 49 patients with high-grade (70%-99%) internal carotid artery (ICA) stenosis or occlusion and 30 healthy subjects. Mean blood flow velocities (MBFV) and mean reaction time (time to peak velocities) (MRT) in each PCA were measured in the dark (closed eyes) and during white light stimulation (opened eyes, looking at the electric bulb), during three consecutive repetitive periods of 1 minute each. In the group of severe carotid disease patients, there was no difference in MRT in PCA during the white light stimulation (P=0.1), whereas in the dark MRT values showed a statistically significantly prolonged visual evoked response (P=0.02), but with no clinical relevance. MBFV values did not differ significantly during white light stimulation (P=0.1), whereas in the dark the difference was also statistically significant (P=0.03), but with no clinical relevance. On the contrary, in the group of healthy subjects, MRT values differed significantly both during white light stimulation (P=0.0005) and in the dark (P=0.00054), showing a significantly prolonged visual evoked response. During white light stimulation, MBFV showed significant decrease and prolonged vasoreactive response (P=0.004). Prolonged vasoreactive response in PCA in healthy subjects during repetitive measurements may indicate exhaustion of the vasoreactive mechanisms. In carotid disease patients, stable vasoreactive response may indicate that the compensatory mechanisms of the posterior circulation are always maximally engaged to compensate for carotid insufficiency.

The art: neuroscientific approach.

Scientists have for centuries tried to localize and define artistic talent. Modern diagnostic techniques that enable visualization and measurement of brain morphology and function are positron emission tomography (PET), magnetic resonance imaging (MRI), functional transcranial Doppler (fTCD) and some biochemical methods. In the majority of people, the left hemisphere is dominant, but the right hemisphere is considered to be creative, visual, imaginative and intuitive. Right hemisphere is associated with musical skills and good three-dimensional orientation. It is also associated with good coordination and athletic skills. Creative people have less marked hemispheric dominance. Using the functional (fMRI) technique, the activation of visual cortex while watching different kinds of compositions was visible; the specific pattern of cortical activation was identified for looking at the landscapes, portraits, abstract compositions or different combination of colors. For music perception, the interplay of activity on both sides of the brain is necessary. In the right side, the centers for perceiving pitch, certain aspects of melody, harmony, timbre and rhythm are placed, and in the left side the processes of rapid changes in frequency and intensity, both in music and words are taking place. Adaptation of the brain, i.e. brain plasticity can arise upon listening or performing music. It is possible to use music, painting and dancing as an aid in the treatment of somatic, neurologic or psychiatric disorders.

Post-stroke depression.

Depression following a stroke, also referred to as post-stroke depression (PSD), has long been recognized as one of the most common complications of stroke. PSD has significant adverse consequences on the recovery of motor and cognitive deficits, as well as on the risk of mortality associated with stroke. The prevalence of PSD varies over time with an apparent peak 3-6 months after stroke and subsequent decline reaching about 50% of the initial rates at one year. The natural course of major depression after stroke has spontaneous remission typically 1 to 2 years after stroke. However, it has also been observed that depression becomes chronic and may persist for more than 3 years following stroke. On the other hand, minor depression appears to be more variable, with both short-term and long-term depression occurring in these patients. Early recognition of PSD symptoms and introduction of pharmacological treatment is of great importance in the reduction of stroke complications and stroke mortality as well as for better functional outcome.

The efficacy of gabapentin in migraine prophylaxis: an observational open label study.

Migraine is often a chronic and disabling disorder. The objective of our study was to assess the efficacy and safety of gabapentin in the prophylaxis of migraine in patients refractory to other prophylactic treatments. The study included 67 migraine patients, 55 women and 12 men; 52 patients completed this prospective, open-label study. Patients were given 900-1800 mg of gabapentin in 3 doses; the mean duration of treatment was 7.2 months. Reduction in the number of days with headache, pain intensity and number of acute medications was assessed through patient diary. The mean number of migraine days/4 weeks was reduced from 15.8 to 8.6, yielding a reduction of 7.2 migraine days/4 weeks (P=0.001). Pain intensity was reduced by 25% in 14 (26.9%), by 50% in 29 (55.7%) and by 75% in three (5.7%) patients, whereas no improvement was reported by six (11.5%) patients at the end of follow up. A significant reduction was recorded in acute medication use (P=0.001). Adverse events were reported by 32/67 (47.8%) patients, in 15 (22.4%) of them causing discontinuation of the drug. The most frequently reported adverse events were drowsiness, dizziness and slowness. Prophylactic treatment with gabapentin was found to be associated with a significant reduction in the number of days with headache, use of acute medications and pain intensity.

The association of obesity and cerebrovascular disease in young adults--a pilot study.

Obesity has been recognized as an isolated risk factor for stroke. In obese patients, other risk factors for stroke such as hypertension, hyperlipidemia, ischemic heart disease and obstructive sleep apnea are more frequently present. The aim of this study was to assess the presence of obesity among other risk factors for stroke in younger adult patients with ischemic stroke. It was a pilot study performed in ischemic stroke patients aged 18-55. In addition to the routine diagnostic work-up, body height, weight and waist circumference were measured in study patients. The study included 50 patients, 23 female and 27 male. The mean age of male patients was 39.8 +/- 10.5 and of female patients 41.6 +/- 7.7 years. In control group The mean waist circumference was 94.9 +/- 5.8 cm in the control group and 102.6 +/- 9.8 cm in the male stroke group. There was no significant difference in waist circumference between the control and patient female groups and in body mass index among all groups. In younger males, waist circumference could be considered as an important risk factor for stroke.

Neuropathic pain.

Neuropathic pain refers to pain that originates from pathology of the nervous system. Common causes of neuropathic pain are diabetes mellitus, reactivation of herpes zoster, nerve compression or radiculopathy, alcohol, chemotherapy or abuse of some drugs, and trigeminal neuralgia. Specific symptoms of neuropathic pain are mechanical allodynia and cold hyperalgesia. Drugs to treat neuropathic pain can be divided into adjuvant analgesics (antidepressants and anticonvulsants), opioids and topical agents. The use of multiple drug therapies is common in practice. Despite considerable increase in the number of randomized placebo-controlled trials in neuropathic pain in the last few years, the medical treatment of neuropathic pain is still far from being satisfactory, with less than half of patients achieving significant benefit with any pharmacological drug.

Recommendations for neuropathic pain treatment.

Damage to the somatosensory nervous system poses a risk for the development of neuropathic pain. Such an injury to the nervous system results in a series of neurobiological events resulting in sensitization of both the peripheral and central nervous system. The symptoms include continuous background pain (often burning or crushing in nature) and spasmodic pain (shooting, stabbing or "electrical"). The diagnosis of neuropathic pain is based primarily on the history and physical examination finding. Although monotherapy is the ideal approach, rational polypharmacy is often pragmatically used. Several classes of drugs are moderately effective, but complete or near-complete relief is unlikely. Antidepressants and anticonvulsants are most commonly used. Opioid analgesics can provide some relief but are less effective than for nociceptive pain; adverse effects may prevent adequate analgesia. Topical drugs and a lidocaine-containing patch may be effective for peripheral syndromes. Sympathetic blockade is usually ineffective except for some patients with complex regional pain syndrome.