Secondary headache disorders in Turkey, the Middle East, Asia, and Africa: A cross-sectional, multicenter study.

BACKGROUND: This multicenter cross-sectional study aimed to determine the frequency and characteristics of secondary headaches in different geographic regions, including Turkey, the Middle East, Asia, and Africa. METHODS: Patients were admitted to the study on a particular day each week for five consecutive weeks between 1 April and 16 May 2022. Before the study, all researchers underwent a constructed briefing about the use and code of the ICHD-3 criteria. The study was conducted in two stages. In the first stage, data on secondary headaches were compared between the regions. In the second stage, the sub-diagnoses of secondary headaches were analyzed only in Turkey. RESULTS: A total of 4144 (30.0%) of the 13,794 patients reported headaches as the main symptoms at admission. A total of 422 patients were excluded from the study. In total, 1249 (33.4%) of 3722 patients were diagnosed as having secondary headaches (Turkey [n = 1039], Middle East [n = 80], Asia [n = 51], Africa [n = 79]). The frequency of secondary headaches (Turkey 33.6%, Africa 30.1%, Middle East 35.5%, Asia 35.4%) did not differ significantly between the regions (p > 0.05). The most common subtype of secondary headaches was headache attributed to substances or their withdrawal in all the studied regions. There was a female predominance in all regions, but it was lower in Africa than in Turkey. The severity and density of headaches differed significantly between the regions, with patients from Africa reporting milder pain than patients from other regions. In Turkey, the most common sub-diagnoses of secondary headaches were medication overuse headache, idiopathic intracranial hypertension, and cervicogenic headache. CONCLUSION: In the present study, one in three patients with a headache had a secondary headache. Headache attributed to substances or their withdrawal was the most common subtype of secondary headaches in all the studied regions. The female predominance of secondary headaches was lower in Africa than in Turkey. The severity and density of headaches differed significantly between regions, with patients from Africa reporting milder pain.

Interactions between the painful disorders and the autonomic nervous system.

he autonomic nervous system (ANS) controls the heart rate, blood pressure, digestion, respiration, pupillary reactivity, sweating, urination, sexual arousal, and regulates the functions of internal organs. This system provides the homeostasis of the cells, tissues, and organs throughout the body and protects against the disturbances imposed by the external and internal stressors. The ANS has three main divisions: The sympathetic nervous system (SNS), the parasympathetic nervous system (PNS), and the enteric nervous system. In general, the SNS and PNS have opposing effects. Each region belonging to the 'pain matrix' interacts with ANS. The descending system regulates pain and creates a regulatory effect by the contribution of aminergic neurotransmitters. Hypothalamus, amygdala, and periaqueductal gray are the main structures of this regulatory system. Dysfunction of the ANS is frequently observed in pain patients. The SNS induce, facilitate, or potentiate chronic pain. Increased responsiveness of injured sensory nerves to catecholamines, increased expression of α-1 adrenoreceptors on the primary afferent nociceptors and hyperalgesic skin, central sensitization rendering Aß mechanoreceptors, enhanced discharge and sympathetic sprouting in dorsal root ganglia, central sensitization, and dysfunction of the pain modulation is proposed mechanisms. In this review, the anatomical, physiological and pathological aspects of ANS and pain, and laboratory tests to evaluate autonomic functions will be discussed. Pathophysiological role of ANS in migraine, trigeminal autonomic cephalgias, trigeminal neuralgia, peripheral nerve injuries, small fiber neuropathies, myofascial pain syndrome, fibromyalgia, painful joint diseases, visceral pain, phantom limb pain, complex regional pain syndrome, and spinal cord injury will be discussed.

Cognitive impairment and affective disorder: A rare presentation of cerebellar stroke.

The awareness of the "Cerebellar Cognitive Affective Syndrome" (CCAS) as a clinical entity is emerging. The CCAS is characterized by impaired executive functions, linguistic skills, visuospatial cognition and personality change. Here we report a 56-year-old, male teacher who developed acute psychomotor retardation, low energy level, infrequent speech, and mild cognitive decline. Two months before admission, he was initially diagnosed as depression, and later misdiagnosed as encephalitis, which misled him to receive high-dose intravenous steroids and antimicrobial drugs. The Brain MRI revealed multiple posterior cerebellar infarcts predominantly at the lobules VII and VIII. The standard neuropsychological tests were unremarkable; however, the CCAS Scale confirmed the diagnosis. The treatment of depression and secondary prevention of stroke was conducted. In cases that present with features of cognitive and affective disorders but with mild voluntary motor or without typical cerebellar features, the role of posterior cerebellar and vermian pathologies should be considered. The CCAS Scale is an appropriate screening tool to detect these patients and provides a framework for evidence-based treatment.

Small Fiber Functionality in Patients with Diabetic Neuropathic Pain.

OBJECTIVES: Diabetic neuropathic pain is associated with small fiber neuropathy. We aimed to assess the functionality of small fibers in patients with diabetes by using a practical method. DESIGN: Patients with impaired glucose tolerance (IGT), diabetic neuropathic pain (DNP), type II diabetes mellitus without neuropathic pain, and healthy control were included. Axon-reflex flare responses were induced by the intradermal application of capsaicin and histamine at the distal leg. The associated flare characteristics (flare areas and flare intensities) were recorded by using Laser Speckle Contrast Analysis (LASCA). The pain and itch responses were rated while performing LASCA. To verify the structural properties of the small fibers, proximal and distal skin biopsies were performed. RESULTS: DN4, MNSI, NRS, evoked-burning pain scores, and HbA1c levels were the highest in the DNP group. Compatible with length-dependent neuropathy, the distal skin PGP9.5-positive intraepidermal nerve fiber densities (IENFDs) were the lowest, whereas TRPV1-positive IENFDs were the highest in patients with DNP. The distal leg LASCA data showed hypo-functionality in both patients with IGT and DNP and association with disease severity. CONCLUSIONS: There is an unmet need to practically assess the functionality of small fibers in patients with pain. In this study, a practical and objective method that does not need special expertise for the measurement of the functional properties of small fibers by using axon-flare responses is presented. The LASCA method could potentially facilitate a practical, quick (within 5 minutes), and very early diagnosis of small fiber hypo-functionality in both patients with IGT and DNP.

Quantification of Trigeminovascular Hypersensitivity Using Laser Speckle Contrast Analysis in a Patient With Chronic Migraine.

BACKGROUND: Activation of peripheral and/or central trigeminovascular pain pathways are implicated in the pathogenesis of migraine. Small fibers mediate pain, thermal sensation, and autonomic functions. Axon flare response is correlated with local C-fiber activation and calcitonin gene-related peptide release. Laser speckle contrast analysis (LASCA) detects very subtle microcirculatory changes that are not visible to the naked eye. CASE: Axon flare response was elicited by 0.01 mL intradermal (i.d.) histamine introduced to the left forehead, trigeminal nerve ophthalmic branch (V1) skin area. Skin microvascular blood flow data were recorded using a LASCA real-time microcirculation imaging system. In the healthy control, prick stimulus slightly elevated focal skin microcirculation only at the stimulated focal area. However, in our patient with chronic migraine, the unilateral prick stimulation transiently (over 10 to 12 seconds) increased ipsilateral skin microcirculation at all 3 branches of the trigeminal nerve, with a slight expansion across the midline. Left V1 stimulation by i.d. histamine induced not only prominent but also long-lasting (10 to 15 minutes of recording time) axon flare response at the ipsilateral V1, V2, and V3 areas, with an expansion to the contralateral V1 area and without any report of allodynia or hyperalgesia. The treatment decreased axon flare characteristics probably by inhibiting neurogenic inflammation. DISCUSSION: The clinical characteristics and individual response to treatment vary widely across patients with pain. Here, we demonstrated the presence of transient spread of increased microcirculation at the ipsilateral trigeminal nerve, and also across the midline after prick stimulus, whereas a more prominent, widespread, and long-lasting histamine-induced axon flare response occurred in a rare subclass of patient who had chronic migraine with autonomic symptoms. The modulatory effect of the pharmacological intervention has also been objectively quantified by LASCA.

The Clinical Characteristics and Neurophysiological Assessments of the Occipital Cortex in Visual Snow Syndrome With or Without Migraine.

OBJECTIVE: Visual snow syndrome (VS) is mainly characterized by flickering, little dots in both visual fields. The recognition of the clinical entity of VS has been increasing recently. Diagnosis is based on patient reports and not better accounted for by another diagnosis. BACKGROUND: The exact pathophysiology of this syndrome is still unknown. In this study, our aim was to investigate the role of neurophysiological assessments of the occipital cortex in VS patients with (VSm ) or without migraine (VSwom ) and the healthy control (HC). METHODS: To assess the occipital cortex hyperexcitability, we conducted a prospective, observational study to investigate the habituation/potentiation response by repetitive pattern reversal visual evoked potentials (rVEP) and examined the phosphene thresholds (PT) by transcranial magnetic stimulation in VS patients with or without migraine who were admitted to our tertiary headache clinic and the healthy control. RESULTS: Twenty-nine volunteers were recruited. The VSm (n = 10), the VSwom (n = 7), and the HC group (n = 12) did not differ demographically. Flickering and floaters were reported in all VS patients and flickering in the dark was the most distressing symptomatology in both VS groups. Higher VAS scores for palinopsia (trailing), photophobia, and concentration difficulty were more frequently self-reported by VSm patients. The HC demonstrated habituation; however, there was loss of habituation response and decreased PTs in both groups of VS patients. The N1P1 VEP amplitude ratios of the 10th/1st block from right and left eye stimulation disclosed higher values (lack of habituation) in VSm (1.04 ± 0.2 and 1.06 ± 0.2) and the VSwom (1.05 ± 0.2 and 0.96 ± 0.08) patients compared to the healthy control (0.75 ± 0.1 and 0.79 ± 0.1), P = .002 from right eye and P = .003 from left eye. In the post hoc analysis the VS patients did not differ according to the presence of migraine from right or left eye stimulations (both P > .999). The left occipital cortex PTs were lower in VSm (58.00 ± 6.60) and VSwom (62.14 ± 11.53) and higher in the HC (71.33 ± 5.56) P = .009. In the post hoc analysis the VS patients did not differ according to the presence of migraine (P > .999). The right occipital cortex PTs were lower in VSm (60.30 ± 8.15) and VSwom (62.00 ± 10.95), higher in the HC (69.67 ± 8.04); however, statistically, groups did not differ (P = .087). CONCLUSIONS: The loss of habituation and lower threshold for occipital cortex excitability were demonstrated electrophysiologically in VS patients. While statistically significant loss of habituation was seen in both VS patients (with or without migraine) in the right eye, statistically significant loss of habituation in the left eye and decreased threshold of left occipital cortex excitability was seen in visual snow with migraine patients. These findings may provide new insights on "visual snow" pathophysiology and serve as an objective and quantitative assessment tool in VS patients.

Headache in challenging and special circumstances: Pregnancy and lactation.

Headache has special importance during pregnancy and postpartum period. The health-care professionals and patients report headache management as challenging during pregnancy and lactation period. Cautions are recommended in preganancy and lactation due to maternal and fetal/newborn risks. Most headaches in the first trimester are due primary headaches. Nevertheless, the incidence of secondary headaches increase in the last trimester and post-partum period. Red flags prompt early evaluation in a patient with headache. Assessment of headache patient requires a detailed history of the headache characteristics and performing appropriate examinations. Approach to headache and strategies to promote best practice in preganancy and lactation will be reviewed.

Temporal and Spatial Quantification of Pain- Related Small Fiber Functionality Assessed Using Laser Speckle Contrast Analysis.

BACKGROUND: This study aimed to establish a practical method for assessing pain symptomatology and develop criteria for quantifying small fiber functions using laser speckle contrast analysis (LASCA). METHODS: Axon flare responses, which reflect small fiber functions, were induced either by histamine or capsaicin applied to the volar surface of the skin of the left forearm. To inhibit small fiber function, local anesthetic cream was applied to the skin of right forearm. The effects on pain symptomatology (severity/timing) and axon flare responses (temporal/spatial characteristics) were measured using LASCA. To highlight the clinical relevance, this method was applied to 3 different types of patients with small fiber dysfunction. RESULTS: Forty-four forearms of 22 healthy volunteers were tested. Eutectic mixture local anesthetic cream reduced the severity and duration of pain, abolishing or prolonging the latency to reach 3-fold higher levels of basal skin microcirculation levels, and decreasing the area and intensity of flare responses. There were positive correlations between pain symptomatology and flare response characteristics in the control forearm. Similar results were confirmed in neuropathic pain patients. CONCLUSIONS: Pain-related small fiber functions and symptomatology (two-in-one method) can be assessed via histamine- or capsaicin-evoked axon flare responses in as little as 15 minutes. The reduction of small fiber functions are characterized by decrease in flare size/intensity at 5 minutes after stimulation and prolongation/abolishment of the latency to reach 3-fold higher levels of baseline skin microcirculation. LASCA may be applied in the clinic to aid early diagnosis, monitor disease progression, and objectively assess treatment efficacy in patients with neuropathic pain.

Two cases of primary leptomeningeal melanomatosis mimicking subacute meningitis.

Primary involvement of leptomeninges with melanocytic tumours is rarely seen and its diagnosis is challenging. Here we summarise two cases of primary leptomeningeal melanomatosis presenting as subacute meningitis. Both cases have pleocytosis and high protein on cerebrospinal fluid analysis, and demonstrated atypical cells on cytology. On magnetic resonance imaging, there is diffuse leptomeningal thickening and avid enhancement of intracranial and intraspinal leptomeninges. One of them demonstrates T1 shortening due to magnetic effects of melanin, the other case is amelanotic and shows hypointensity on precontrast T1-weighted images. Both cases can be diagnosed with biopsy. In conclusion, these cases highlight the importance of the correct interpretation of cytological and magnetic resonance imaging findings in patients with atypical findings.

Ocular Surface Alterations in the Context of Corneal In Vivo Confocal Microscopic Characteristics in Patients With Fibromyalgia.

PURPOSE: To quantify the morphology of corneal basal epithelium and subbasal nerves and to evaluate the ocular surface alterations in patients with fibromyalgia (FM). METHODS: Patients with FM (n = 34) and healthy controls (n = 42) were enrolled. All participants underwent ocular surface tests in the following order: corneal sensitivity, tear film breakup time, lissamine green staining, Schirmer test, and the Ocular Surface Disease Index questionnaire. Basal epithelial cells and subbasal nerves were evaluated using in vivo confocal microscopy (IVCM). Demographic characteristics, Visual Analog Scale for Pain (VAS), American College of Rheumatology 1990, the Widespread Pain Index (WPI), and the Symptom Impact Questionnaire (SIQR) scores of patients with FM were obtained. RESULTS: Corneal sensitivity was 0.4 g/mm (fiber length: 6.0 cm) in all eyes. Patients with FM had a higher Ocular Surface Disease Index (42.2 ± 18.9 vs. 1.2 ± 1.7, P < 0.001), higher lissamine green staining scores (0.5 ± 0.5 vs. 0.05 ± 0.2, P < 0.001), and lower tear breakup time scores (9.0 ± 3.6 vs. 10.3 ± 1.5, P = 0.003) than the controls. Basal epithelial cell density (2709 ± 494 vs. 4491 ± 724), total nerve density (1563 ± 620 vs. 2545 ± 973), long nerve fibers (3.4 ± 1.3 vs. 4.5 ± 1.0), and the number of nerves (5.0 ± 1.8 vs. 10.3 ± 2.1) were all lower in patients with FM compared with those of the controls (P < 0.001 for all). There was a statistically significant negative correlation between the WPI score and Schirmer test results (rho = -0.374, P = 0.03) and between WPI and total nerve density (rho = -0.334, P = 0.054). CONCLUSIONS: To the best of our knowledge, this is the first study that evaluated ocular surface alterations in the context of corneal IVCM characteristics. Patients with FM should be evaluated in terms of ocular surface diseases. IVCM may be used in FM to assess small fiber neuropathy.

Preventive drugs restore visual evoked habituation and attention in migraineurs.

Visual system pathway dysfunction has been postulated in migraineurs. We wanted to investigate if any difference exists interictally in visual attention and visual evoked habituation of frequently attacked migraineurs compared to the healthy control group. The effects of 3-month prophylactic migraine treatment on these parameters were also assessed. The migraineurs at headache-free interval (n = 52) and age, sex-matched healthy controls (n = 35) were compared by habituation response to 10 blocks of repetitive pattern-reversal visual stimuli (each block consisted 100 responses). The amplitude changes of 5th and 10th blocks were further compared with that of block 1 to assess the response of habituation (i.e., decrease) or potentiation (i.e., increase). The level of sustained visual attention was assessed by Cancellation test. Migraineurs were randomized to three different preventive treatments: propranolol 40 mg tid, flunarizine 5 mg bid, or topiramate 50 mg bid. After 3 months of preventive treatment, migraineurs data were compared with their baseline values. The groups did not differ by sex and age. In electrophysiological studies, the habituation ability observed in the healthy group was not observed in migraineurs. However, it was restored 3 months after preventive treatment. In migraineurs, compared to their baseline values, the distorted visual attention parameters also improved after treatment. All drugs were effective. The loss of habituation ability and low visual attention performance in migraineurs can be restored by migraine preventive treatment. This electrophysiological study accompanied by neuropsychological test may aid an objective and quantitative assessment tool for understanding migraine pathophysiology.

Visual Snow in Migraine With Aura: Further Characterization by Brain Imaging, Electrophysiology, and Treatment--Case Report.

OBJECTIVE: This study aims to investigate characteristics of visual snow accompanied by migraine and special interest on occipital bending, electrophysiological properties, and response to treatment. BACKGROUND: Visual snow is characterized by continuous dynamically flickering dots in the visual field. Most patients also have comorbid migraine. Cortical hyperexcitability is a feature of migraine. Recent studies indicate an association between occipital bending with psychiatric disorders such as depression. Here, we demonstrate a patient with visual snow, migraine with aura, left occipital bending, and cortical hyperexcitability. Treatment response to lamotrigine was objectively assessed by repetitive pattern reversal visual evoked potentials (rVEP). METHODS: A 25-year-old woman with a 10-year history of migraine with aura (2-3 attacks/week) admitted for 1-year history of visual snow. She reported continuous bright and colorful lights, palinopsia, floaters, nyctalopsia, and photopsia. Brain magnetic resonance imaging (MRI) was performed. Visual habituation response was assessed before and after lamotrigine treatment by rVEP. RESULTS: Brain MRI revealed left occipital bending. On rVEP study, there was potentiation response. After lamotrigine treatment, the patient had no more complaints of visual snow, was able to sleep, and the frequency of migraine decreased to 2 attacks/month. Electrophysiologically, the cortical hyperexcitability was improved. CONCLUSIONS: The visual snow and loss of habituation ability in migraine associated with occipital bending can be improved with lamotrigine treatment. This report may provide new insights on "visual snow" pathophysiology in migraine.

A Rare Association of Trigeminal Autonomic Cephalgia: Pontine Capillary Telangiectasia.

This report describes a case of pontine capillary telangiectasia in a 43-year-old woman with a clinical diagnosis of trigeminal autonomic cephalgia. The possible association with pontine capillary telangiectasia and trigeminal autonomic cephalgia is discussed.

The long-term changes in pain-related symptomatology of inguinal hernia following 2 different herniorrhaphy techniques.

BACKGROUND/AIM: To compare the changes in pain-related symptoms of inguinal hernias from initial admission to postoperative month 6 following 2 herniorrhaphy techniques. MATERIALS AND METHODS: Patients with unilateral inguinal hernias were scheduled for either Lichtenstein or self-gripping polypropylene mesh repair. Patients were preoperatively evaluated with a visual analog scale (VAS) and a Turkish version ofthe Douleur Neuropathique 4 (DN4) questionnaire and the complaints related to pain were noted. After surgery, patients were discharged without early complications. Patients were reassessed at postoperative month 6. The late-term complaints of pain as well as neurological findings were evaluated using the VAS and the Turkish version of the DN4 questionnaire. Quality of life was also assessed with the Nottingham Health Profile (NHP). RESULTS: Thirty-four patients underwent conventional Lichtenstein repair and 19 patients underwent self-gripping polypropylene mesh repair. Even though decreases in VAS intensity scores for both hernia repair techniques were noted at postoperative month 6 when compared to the preoperative period, no significant changes were found in pain, VAS, total DN4, or NHP scores between groups. CONCLUSION: Despite its ease of application and short time duration, self-gripping polypropylene mesh repair was not found to be superior to conventional Lichtenstein hernia repair in terms of reducing pain related to inguinal hernia.

Duration of migraine is associated with cardiac diastolic dysfunction.

OBJECTIVE: Migraine is a common type of headache accompanied or preceded by signs of central and autonomic nervous system dysfunction. Autonomic dysfunction has been suggested to be a potential contributor to impaired cardiac diastolic function. Cardiac diastolic dysfunction is characterized by normal left ventricular contractility but impaired ventricular relaxation. It is a growing clinical entity implicated in morbidity and mortality due to heart failure. The aim of this study was to determine if any relationship exists between migraine and diastolic dysfunction. METHODS: Migraineurs (N = 55), and age- and sex-matched healthy controls (N = 52) were evaluated by conventional and tissue Doppler echocardiography. Migraine-related disability in the previous 3 months was assessed by the Migraine Disability Assessment questionnaire. Baseline characteristics were recorded, and blood samples were collected. RESULTS: The groups did not differ in terms of sex or age. The migraine group had higher lipid levels compared with the control group. Diastolic dysfunction was significantly higher among the 30 migraineurs with a history of migraine of 10 years or more compared with the 25 migraineurs with a history of less than 10 years, (P = 0.003). In logistic regression analysis, migraine duration was shown to be an independent predictor of diastolic dysfunction (odds ratio 1.130, 95% confidence interval, P = 0.044). CONCLUSIONS: Cardiac diastolic dysfunction is associated with migraine. A long history of migraine is an independent predictor of diastolic dysfunction.

Comparing partial and total tibial-nerve axotomy: long-term effects on prevalence and location of evoked pain behaviors.

Monophasic (one-time) nerve injuries heal without clinically significant residua in most cases, but rare individuals are left with neuropathic pain, even after seemingly minor lesions. The effects of lesion size on risk for chronic pain persistence are not well understood, particularly as concerns the complex regional pain syndrome, which is defined in part by pain "disproportionate" to the severity of the causative lesion, and extending outside the autonomous territory of a single nerve. To better clarify the expected prevalence of pain behaviors after nerve injury, we compared the effects in rats of different-sized axotomies on the prevalence and location of evoked pain behaviors. To highlight clinical relevance, we also describe a patient with iatrogenic tibial-nerve injury causing similar chronic neuralgia. Adult male Sprague-Dawley rats were anesthetized and had either 1/3, 2/3 or their entire left tibial nerves tightly ligated at two sites just below the sciatic trifurcation and the interposed nerve was cut. Unoperated rats provided controls. Sensory function in the tibial and sural-innervated territories of both plantar hindpaws was assessed for as long as 6 months postoperatively. Soon after surgery, evoked pain behavior developed in the ipsilesional sural-innervated site in a subset of axotomized rats and recovery was variable. The relationship between lesion size and prevalence and severity of hyperalgesia varied for different pain behaviors, with pinprick hyperalgesia clearly more likely after larger axotomies. In summary, partial tibial-nerve injury in rats models human disease and suggests that expectations of proportionality between lesion size and development of neuropathic pain may need revision.

Alpha-synuclein aggregation induced by brief ischemia negatively impacts neuronal survival in vivo: a study in [A30P]alpha-synuclein transgenic mouse.

Alpha-synuclein oligomerization and aggregation are considered to have a role in the pathogenesis of neurodegenerative diseases. However, despite numerous in vitro studies, the impact of aggregates in the intact brain is unclear. In vitro, oxidative/nitrative stress and acidity induce α-synuclein oligomerization. These conditions favoring α-synuclein fibrillization are present in the ischemic brain, which may serve as an in vivo model to study α-synuclein aggregation. In this study, we show that 30-minute proximal middle cerebral artery (MCA) occlusion and 72 hours reperfusion induce oligomerization of wild-type α-synuclein in the ischemic mouse brain. The nonamyloidogenic isoform ß-synuclein did not form oligomers. Alpha-synuclein aggregates were confined to neurons and colocalized with ubiquitin immunoreactivity. We also found that 30 minutes proximal MCA occlusion and 24 hours reperfusion induced larger infarcts in C57BL/6(Thy1)-h[A30P]alphaSYN transgenic mice, which have an increased tendency to form synuclein fibrils. Trangenics also developed more selective neuronal necrosis when subjected to 20 minutes distal MCA occlusion and 72 hours reperfusion. Enhanced 3-nitrotyrosine immunoreactivity in transgenic mice suggests that oxidative/nitrative stress may be one of the mechanisms mediating aggregate toxicity. Thus, the increased vulnerability of transgenic mice to ischemia suggests that α-synuclein aggregates not only form during ischemia but also negatively impact neuronal survival, supporting the idea that α-synuclein misfolding may be neurotoxic.

A comparison of the DN4 and LANSS questionnaires in the assessment of neuropathic pain: validity and reliability of the Turkish version of DN4.

UNLABELLED: A screening tool that quickly and correctly differentiates neuropathic pain from non-neuropathic pain is essential. Although there are many screening tools in the assessment of neuropathic pain, many physicians still have the problem of not being able to identify their neuropathic pain patients easily. In this study, we assessed the test-retest reliability, internal consistency, and validity of the Turkish version of DN4 questionnaire. Within the same group of patients, we also compared the DN4 with the LANSS questionnaire. A total of 180 patients (n = 121 with neuropathic pain and n = 59 with non-neuropathic pain characteristics) were enrolled. In our study population, peripheral origin of neuropathic pain, mainly radiculopathies and polyneuropathies, dominated. The reliability and validity of Turkish version of DN4 were found to be high. The sensitivities of the DN4 and the LANSS were 95% and 70.2%, respectively. The specificity of both tests was 96.6%. The strengths and weaknesses of these questionnaires are discussed. PERSPECTIVE: The Turkish version of DN4 questionnaire is reliable and valid. It is also an easier, quicker, and more sensitive screening tool (1-minute test) compared with the Turkish version of LANSS questionnaire. These features of the DN4 may help clinicians to identify their neuropathic pain patients accurately in daily clinical practice and research studies.