Cutaneous Allodynia in Migraine

Pakistan Journal of Neurological Sciences (PJNS)

Volume 15 Issue 1 Article 8

3-2020

Cutaneous allodynia in migraine

Dr. Ghulam Shabbir Pakistan Institute of Medical Sciences Islamabad

Dr. Haris Majid Rajput Pakistan Institute of Medical Sciences Islamabad

Dr. Zakir Jan Pakistan Institute of Medical Sciences Islamabad

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Recommended Citation Shabbir, Dr. Ghulam; Majid Rajput, Dr. Haris; and Jan, Dr. Zakir (2020) "Cutaneous allodynia in migraine," Pakistan Journal of Neurological Sciences (PJNS): Vol. 15 : Iss. 1 , Article 8. Available at: https://ecommons.aku.edu/pjns/vol15/iss1/8 ORIGINAL ARTICLE

The aim of our research was to find out the relation Cutaneous allodynia severity was defined according to The proposed reason for allodynia is the sensitization of of signs and symptoms of cutaneous allodynia. CUTANEOUS ALLODYNIA IN MIGRAINE between migraine and cutaneous allodynia. For score i.e No allodynia if score was 0-2, mild allodynia if the nociceptive neurons in central pain pathway. As In another study by Ashkenazi et al 20 on which they allodynia we used Cutaneous Allodynia Checklist (ASC), score was 3-5, moderate allodynia if score was 6-8 and disease progresses and its duration increases the found the prevalence of allodynia in migraine patients Dr. Ghulam Shabbir1, Dr. Haris Majid Rajput2, Dr. Zakir Jan3 table-17 to describe the frequency and characteristics severe allodynia with a score of 9 or more. The data frequency of allodynia also increases. All patients were up to 80%. Usually the patients become sensitive to 1Resident Neurologist , 2 Assistant Professor Neurology, 3Assistant Professor Neurology Pakistan Institute of Medical Sciences Islamabad of cutaneous allodynia in migraine population. was entered on a standard performa and analyzed by examined and interviews directly and by the authors pain even during attack free periods of migraine but as using SPSS version 17. Mean and standard deviations themselves. By using the 12-items Allodynia Symptoms far as the allodynia is concerned when patients were Correspondence to: Dr. Ghulam Shabbir Email: [email protected] Table-1: were calculated for numerical variables. Frequencies Checklist, we found the frequency percentage of enquired about abnormal dermal response they denied Date of submission: October 17, 2019 Date of revision: December 22, 2019 Date of acceptance: January 3,2020 12‐item Allodynia Symptom Checklist (ASC‐12) and percentages were calculated categorical variables. cutaneous allodynia in migraine sufferers was up to 56 any symptoms of cutaneous allodynia during headache percent with varying degrees of symptoms of allodynia free periods suggesting its reversible nature. RESULTS: ranging from mild to severe depending upon ASC-12 ABSTRACT: items score. Our study is consistent with the findings of LIMITATIONS A total of 200 patients were enrolled in this study. The an international study by Lipton et al 17 that showed a mean age of the patient was 33 years. Out of 200 It is a single centre study. Frequency in non-migraine OBJECTIVE: Objective of this study is to find out the presence and severity of cutaneous allodynia in migraine presence of cutaneous allodynia up to 63% among patients 142 (71 %) were females and 58 (29 %) were patients is not checked in this study. Associations of sufferers. migraineurs with severe allodynia present in 20.3% of males as shown in table 2. Out of 200 patients 111 cutaneous allodynea especially with duration and migraineurs. Presence and severity of allodynia BACKGROUND: Cutaneous allodynia is the perception of pain in response to non noxious stimuli. It occurs due to (55.5 %) had some symptoms of cutaneous allodynia severity of migraine as well as its impact on activities of indicates the migraine severity actually indicating repeated stimulations that lead to sensitization and abnormal skin response. while 89 patients (44.5 %) didn’t show any symptoms daily living was not exercised. Validated scales for CA prompt treatment as the increased frequency of of cutaneous allodynia as shown in table-3. Out of 111 assessment not available in other languages. MATERIALS AND METHODS: It was a descriptive case study and conducted at Neurology department Pakistan allodynia indicates the long term disease activity. Just patients who were positive for cutaneous allodynia 51 Institute of Medical Sciences from June 2017 to May 2018. All patients of both genders above age 13 years of age like migraine headache that has many aggravated patients (45.9%) showed mild degree of cutaneous CONCLUSION: with migraine diagnosed as having “Migraine without aura” or “Migraine with aura” according to the International factors, cutaneous allodynia after sensitization involving allodynia, 38 patients (34.2%) showed moderate and Headache society criteria, ICHD-3 beta, were enrolled in this study. Cutaneous allodynia was evaluated by using the central process responds to even the trivial stimuli This study shows the presence and severity of allodynia 22 patients (19.8%) showed severe degree of Allodynia Symptom Checklist that consisted of 12-items. Cutaneous allodynia severity was defined according to score from inside as well as outside the brain. Young WB et al in migraine population. Increased skin sensitivity can cutaneous allodynia as shown in table-4. i.e No allodynia if score was 0-2, mild allodynia if score was 3-5, moderate allodynia if score was 6-8 and severe 18 showed in their study that frequent migraine be determined by simple and relevant questioning allodynia with a score of 9 or more. headache attacks are responsible for occurrence about activities such as brushing hair, touching the Table-2: Gender distribution allodynia that favours the concept of sensitization scalp, shaving, and wearing glasses, contact lenses, RESULTS: A total of 200 patients were enrolled in study with a mean age of 33 years. 142 patients (71%) were leading to abnormal and enhanced dermal response to earrings, or wearing tight clothes hurt patients during females and 58 patients (29%) were males. 111 patients (55.5%) showed signs and symptoms of cutaneous non irritating stimuli even. Prolonged duration of migraine attacks. allodynia while 89 patients (44.5%) were negative for cutaneous allodynia symptoms. Out of 111 patients who were disorder and chronicity are related to higher positive for cutaneous allodynia 51 patients (45.9%) showed mild degree of cutaneous allodynia, 38 patients percentages of derangements and alteration in (34.2%)showed moderate and 22 patients (19.8%) showed severe degree of cutaneous allodynia processing of sensory stimuli in the cerebral cortex 19. CONCLUSION: This study shows the presence and severity of allodynia in migraine population. Increased skin So the proposed structural changes in Table-3: Cutaneous Allodynia positive and negative sensitivity can be determined by simple and relevant questioning about activities such as brushing hair, touching the trigeminovascular excitability pathway as well as some patients. scalp, shaving, and wearing glasses, contact lenses, earrings, or wearing tight clothes hurt patients during migraine other pain-modulating systems in the brainstem are attacks. also thought to be involved in the process of happening Key words: Migraine, Allodynia

INTRODUCTION: Migraine is a chronic debilitating system as well as sensitization producing altered skin MATERIALS AND METHODS: disorder having many complications including allodynia sensations, a condition named as cutaneous that affect the quality of life. Cutaneous allodynia (CA) allodynia.6 A lot of studies done before suggest the This was a descriptive case study conducted in Table-4: Severity of Cutaneous Allodynia. refers to the comprehension of pain or discomfort in prevalence of cutaneous allodynia up to 80% in department of neurology, Pakistan Institute of Medical response to non-noxious stimuli applied to skin.1 When patients with migraine especially during acute Sciences for a period of 1 year from June 2017 to May a stimulus is repeated again and again it causes exacerbation.7 Those migraineurs who have more 2018 after taking permission from ethical committee of sensitization. This process leads to early frequents attacks are more prone to have allodynia8, the hospital. A total of 200 patients were enrolled using responsiveness by neurons.2 In facial cutaneous prevalence is more if the duration of migraine is non probability consecutive sampling. Sample size was allodynia there is involvement of trigeminal nucleus prolong.9 Studies showed the presence of abnormal calculated using WHO sample size calculator. An caudalis. It has nociceptive neurons and receives cutaneous sensations for sometimes even after the informed written consent was taken from all the patients. All patients of both genders above age 13 afferent from meninges especially the dura, facial skin, migraine attack has been aborted, these findings DISCUSSION: mucosa, teeth, tongue and jaw.3,4 These neurons after strengthen the mechanism of involvement of trigeminal years of age with migraine diagnosed as having receiving input from areas inside as well as outside the pain pathway and central sensitization.10 This theory is “Migraine without aura” or “Migraine with aura” Cutaneous allodynia is the feeling of discomfort and brain produce different responses leading to headache also supported by the presence of symptoms in according to the International Headache society pain to the stimuli that usually do no cause pain. It is and abnormal cutaneous sensations.5 All these transformed migraine.11-13 There are three categories of criteria, ICHD-3 beta, were enrolled in this study16. one of the several complications of migraine that processes lead to change or alteration of normal cutaneous allodynia including thermal, dynamic Cutaneous allodynia was evaluated by using Allodynia develop due to chronicity as the disease progresses electrophysiological functions of central nervous mechanical and static mechanical.14,15 Symptom Checklist that consisted of 12-items. and affect the outcome measures in disease course.

PAKISTAN JOURNAL OF NEUROLOGICAL SCIENCES 05 VOL. 15 (1) JAN-MARCH 2020 The aim of our research was to find out the relation Cutaneous allodynia severity was defined according to The proposed reason for allodynia is the sensitization of of signs and symptoms of cutaneous allodynia. between migraine and cutaneous allodynia. For score i.e No allodynia if score was 0-2, mild allodynia if the nociceptive neurons in central pain pathway. As In another study by Ashkenazi et al 20 on which they allodynia we used Cutaneous Allodynia Checklist (ASC), score was 3-5, moderate allodynia if score was 6-8 and disease progresses and its duration increases the found the prevalence of allodynia in migraine patients table-17 to describe the frequency and characteristics severe allodynia with a score of 9 or more. The data frequency of allodynia also increases. All patients were up to 80%. Usually the patients become sensitive to of cutaneous allodynia in migraine population. was entered on a standard performa and analyzed by examined and interviews directly and by the authors pain even during attack free periods of migraine but as using SPSS version 17. Mean and standard deviations themselves. By using the 12-items Allodynia Symptoms far as the allodynia is concerned when patients were Table-1: were calculated for numerical variables. Frequencies Checklist, we found the frequency percentage of enquired about abnormal dermal response they denied 12‐item Allodynia Symptom Checklist (ASC‐12) and percentages were calculated categorical variables. cutaneous allodynia in migraine sufferers was up to 56 any symptoms of cutaneous allodynia during headache percent with varying degrees of symptoms of allodynia free periods suggesting its reversible nature. Question: How often do you Does not Never Rarely Less than Half of RESULTS: ranging from mild to severe depending upon ASC-12 experience increased pain or apply to half of the items score. Our study is consistent with the findings of LIMITATIONS an unpleasant sensation on me the time or A total of 200 patients were enrolled in this study. The an international study by Lipton et al 17 that showed a your skin during your most time more mean age of the patient was 33 years. Out of 200 It is a single centre study. Frequency in non-migraine severe type of headache presence of cutaneous allodynia up to 63% among patients 142 (71 %) were females and 58 (29 %) were patients is not checked in this study. Associations of when you engage each of the migraineurs with severe allodynia present in 20.3% of males as shown in table 2. Out of 200 patients 111 cutaneous allodynea especially with duration and following? migraineurs. Presence and severity of allodynia Score: 0 Score: 0 Score: 0 Score: 1 Score: 2 (55.5 %) had some symptoms of cutaneous allodynia severity of migraine as well as its impact on activities of indicates the migraine severity actually indicating Wearing a necklace while 89 patients (44.5 %) didn’t show any symptoms daily living was not exercised. Validated scales for CA prompt treatment as the increased frequency of Wearing earrings of cutaneous allodynia as shown in table-3. Out of 111 assessment not available in other languages. allodynia indicates the long term disease activity. Just Wearing glasses patients who were positive for cutaneous allodynia 51 Wearing tight clothes like migraine headache that has many aggravated patients (45.9%) showed mild degree of cutaneous CONCLUSION: Wearing a pony tail factors, cutaneous allodynia after sensitization involving allodynia, 38 patients (34.2%) showed moderate and Wearing contact lenses the central process responds to even the trivial stimuli This study shows the presence and severity of allodynia 22 patients (19.8%) showed severe degree of Shaving the face from inside as well as outside the brain. Young WB et al in migraine population. Increased skin sensitivity can Taking a shower cutaneous allodynia as shown in table-4. 18 Combing the hair showed in their study that frequent migraine be determined by simple and relevant questioning headache attacks are responsible for occurrence about activities such as brushing hair, touching the Resting the head on a pillow Table-2: Gender distribution Exposure to cold allodynia that favours the concept of sensitization scalp, shaving, and wearing glasses, contact lenses, Exposure to heat Frequency Percent % leading to abnormal and enhanced dermal response to earrings, or wearing tight clothes hurt patients during Total score: Valid Male 58 29 non irritating stimuli even. Prolonged duration of migraine attacks. Sum of score: Female 142 71 disorder and chronicity are related to higher Total 200 100.0 percentages of derangements and alteration in Allodynia ASC range processing of sensory stimuli in the cerebral cortex 19. None 0-2 So the proposed structural changes in Table-3: Cutaneous Allodynia positive and negative Mild trigeminovascular excitability pathway as well as some 3-5 patients. Moderate 6-8 other pain-modulating systems in the brainstem are also thought to be involved in the process of happening Severe 9 or more Frequency Percent % Valid Positive 111 55.5 Negative 89 44.5 Total 200 100.0 MATERIALS AND METHODS: This was a descriptive case study conducted in Table-4: Severity of Cutaneous Allodynia. department of neurology, Pakistan Institute of Medical Sciences for a period of 1 year from June 2017 to May CA Frequency Percent % 2018 after taking permission from ethical committee of Negative 89 44.5 Mild 51 25.5 the hospital. A total of 200 patients were enrolled using Moderate 38 19.0 non probability consecutive sampling. Sample size was Severe 22 11.0 calculated using WHO sample size calculator. An Total 200 100.0 informed written consent was taken from all the patients. All patients of both genders above age 13 DISCUSSION: years of age with migraine diagnosed as having “Migraine without aura” or “Migraine with aura” Cutaneous allodynia is the feeling of discomfort and according to the International Headache society pain to the stimuli that usually do no cause pain. It is criteria, ICHD-3 beta, were enrolled in this study16. one of the several complications of migraine that Cutaneous allodynia was evaluated by using Allodynia develop due to chronicity as the disease progresses Symptom Checklist that consisted of 12-items. and affect the outcome measures in disease course.

PAKISTAN JOURNAL OF NEUROLOGICAL SCIENCES 06 VOL. 15 (1) JAN-MARCH 2020 The aim of our research was to find out the relation Cutaneous allodynia severity was defined according to The proposed reason for allodynia is the sensitization of of signs and symptoms of cutaneous allodynia. disorders. J Electromyogr Kinesiol. 2004;14:87-93. 2006;26:852-856. between migraine and cutaneous allodynia. For score i.e No allodynia if score was 0-2, mild allodynia if the nociceptive neurons in central pain pathway. As In another study by Ashkenazi et al 20 on which they 7. Jakubowski M, Silberstein S, Ashkenazi A, Burstein 14. Woolf CJ, Wall PD. Relative effectiveness of C allodynia we used Cutaneous Allodynia Checklist (ASC), score was 3-5, moderate allodynia if score was 6-8 and disease progresses and its duration increases the found the prevalence of allodynia in migraine patients R. Can allodynic migraine patients be identified primary afferent fibers of different origins in evoking a table-17 to describe the frequency and characteristics severe allodynia with a score of 9 or more. The data frequency of allodynia also increases. All patients were up to 80%. Usually the patients become sensitive to interictally using a questionnaire? Neurology. prolonged facilitation of the flexor reflex in the rat. J of cutaneous allodynia in migraine population. was entered on a standard performa and analyzed by examined and interviews directly and by the authors pain even during attack free periods of migraine but as 2005;65:1419-1422. Neurosci 1986;6:1433–1442. using SPSS version 17. Mean and standard deviations themselves. By using the 12-items Allodynia Symptoms far as the allodynia is concerned when patients were Table-1: were calculated for numerical variables. Frequencies Checklist, we found the frequency percentage of enquired about abnormal dermal response they denied 8. Lipton RB, Bigal ME, Ashina S, et al. Cutaneous 15. Jakubowski M, Silberstein S, Ashkenazi A, 12‐item Allodynia Symptom Checklist (ASC‐12) and percentages were calculated categorical variables. cutaneous allodynia in migraine sufferers was up to 56 any symptoms of cutaneous allodynia during headache allodynia in the migraine population. Ann Neurol. Burstein R. Can allodynic migraine patients be percent with varying degrees of symptoms of allodynia free periods suggesting its reversible nature. 2008;63:148-158. identified interictally using a questionnaire? RESULTS: ranging from mild to severe depending upon ASC-12 Neurology 2005;65:1419 –1422. items score. Our study is consistent with the findings of LIMITATIONS 9. Mathew NT, Kailasam J, Seifert T. Clinical A total of 200 patients were enrolled in this study. The an international study by Lipton et al 17 that showed a recognition of allodynia in migraine. Neurology. 16. Headache Classification Committee of the mean age of the patient was 33 years. Out of 200 It is a single centre study. Frequency in non-migraine presence of cutaneous allodynia up to 63% among 2004;63: 848-852. International Headache Society (2013) The patients 142 (71 %) were females and 58 (29 %) were patients is not checked in this study. Associations of migraineurs with severe allodynia present in 20.3% of International Classification of Headache Disorders, males as shown in table 2. Out of 200 patients 111 cutaneous allodynea especially with duration and migraineurs. Presence and severity of allodynia 10. Weissman-Fogel I, Sprecher E, Granovsky Y, 3rd edition (beta version). Cephalalgia 33: 629–808. (55.5 %) had some symptoms of cutaneous allodynia severity of migraine as well as its impact on activities of indicates the migraine severity actually indicating Yarnitsky D. Repeated noxious stimulation of the skin while 89 patients (44.5 %) didn’t show any symptoms daily living was not exercised. Validated scales for CA prompt treatment as the increased frequency of enhances cutaneous pain perception of migraine 17. Lipton RB, Bigal ME, Ashina S, et al. Cutaneous of cutaneous allodynia as shown in table-3. Out of 111 assessment not available in other languages. allodynia indicates the long term disease activity. Just patients in-between attacks: Clinical evidence for allodynia in the migraine population. Ann Neurol. patients who were positive for cutaneous allodynia 51 like migraine headache that has many aggravated continuous sub-threshold increase in membrane 2008;63:148-158. ))))) USE IN DISCUSSION.. patients (45.9%) showed mild degree of cutaneous CONCLUSION: factors, cutaneous allodynia after sensitization involving excitability of central trigeminovascular neurons. Pain. BOTH OF AVBOVE allodynia, 38 patients (34.2%) showed moderate and the central process responds to even the trivial stimuli This study shows the presence and severity of allodynia 2003;104:693-700. 22 patients (19.8%) showed severe degree of from inside as well as outside the brain. Young WB et al in migraine population. Increased skin sensitivity can 18. Young WB, Richardson ES, Shukla P. Brush cutaneous allodynia as shown in table-4. 18 showed in their study that frequent migraine be determined by simple and relevant questioning 11. BigalME,Ashina S,Burstein R,et al. Prevalence allodynia in hospitalized headache patients. headache attacks are responsible for occurrence about activities such as brushing hair, touching the and characteristics of allodynia in headache Headache 2005;45:999 –1003. Table-2: Gender distribution allodynia that favours the concept of sensitization scalp, shaving, and wearing glasses, contact lenses, sufferers:A population study. Neurology. leading to abnormal and enhanced dermal response to earrings, or wearing tight clothes hurt patients during 2008;70:1525-1533. 19. Aurora SK. Spectrum of illness: Understanding non irritating stimuli even. Prolonged duration of migraine attacks. biological patterns and relationships in chronic disorder and chronicity are related to higher 12. Cooke L, Eliasziw M, Becker WJ. Cutaneous migraine. Neurology. 2009;72:8–13. percentages of derangements and alteration in allodynia in transformed migraine patients. processing of sensory stimuli in the cerebral cortex 19. Headache. 2007;47:531-539. 20. Ashkenazi A, Silberstein S, Jakubowski M, So the proposed structural changes in Burstein R. Improved identification of allodynic Table-3: Cutaneous Allodynia positive and negative trigeminovascular excitability pathway as well as some 13. LoPinto C, Young WB, Ashkenazi A. Comparison migraine patients using a questionnaire. Cephalalgia. patients. other pain-modulating systems in the brainstem are of dynamic (brush) and static (pressure) mechanical 2007;27: 325-329. also thought to be involved in the process of happening allodynia in migraine. Cephalalgia.

MATERIALS AND METHODS: References: This was a descriptive case study conducted in Table-4: Severity of Cutaneous Allodynia. department of neurology, Pakistan Institute of Medical 1. Burstein R, Yarnitsky D, Goor-Aryeh I, Ransil BJ, 4. Sessle BJ, Hu JW, Amano N, Zhong G. Convergence Sciences for a period of 1 year from June 2017 to May Bajwa ZH. An association between migraine and of cutaneous, tooth pulp, visceral, neck and muscle 2018 after taking permission from ethical committee of cutaneous allodynia. Ann Neurol. 2000;47:614-624. afferents onto nociceptive and non-nociceptive the hospital. A total of 200 patients were enrolled using 1342 October 2009 neurones in trigeminal subnucleus caudalis (medullary non probability consecutive sampling. Sample size was dorsal horn) and its implications for referred pain. Pain calculated using WHO sample size calculator. An 2. Baranauskas G, Nistri A. Sensitization of pain 1986;27:219 –235. informed written consent was taken from all the pathways in the spinal cord: Cellular mechanisms. Prog patients. All patients of both genders above age 13 Neurobiol. 1998;54:349-365. 5. Woolf CJ. Central sensitization: Implications for the DISCUSSION: years of age with migraine diagnosed as having diagnosis and treatment of pain. Pain. “Migraine without aura” or “Migraine with aura” Cutaneous allodynia is the feeling of discomfort and 3. Burstein R, Cutrer MF, Yarnitsky D. The development 2011;152:S2–S15. according to the International Headache society pain to the stimuli that usually do no cause pain. It is of cutaneous allodynia during a migraine attack: clinical criteria, ICHD-3 beta, were enrolled in this study16. one of the several complications of migraine that evidence for the sequential recruitment of spinal and 6. Winkelstein BA. Mechanisms of central sensitization, Cutaneous allodynia was evaluated by using Allodynia develop due to chronicity as the disease progresses supraspinal nociceptive neurons in migraine. Brain neuroimmunology and injury biomechanics in Symptom Checklist that consisted of 12-items. and affect the outcome measures in disease course. 2000;123:1703–1709. persistent pain: Implications for musculoskeletal

PAKISTAN JOURNAL OF NEUROLOGICAL SCIENCES 07 VOL. 15 (1) JAN-MARCH 2020 disorders. J Electromyogr Kinesiol. 2004;14:87-93. 2006;26:852-856. 7. Jakubowski M, Silberstein S, Ashkenazi A, Burstein 14. Woolf CJ, Wall PD. Relative effectiveness of C R. Can allodynic migraine patients be identified primary afferent fibers of different origins in evoking a interictally using a questionnaire? Neurology. prolonged facilitation of the flexor reflex in the rat. J 2005;65:1419-1422. Neurosci 1986;6:1433–1442.

8. Lipton RB, Bigal ME, Ashina S, et al. Cutaneous 15. Jakubowski M, Silberstein S, Ashkenazi A, allodynia in the migraine population. Ann Neurol. Burstein R. Can allodynic migraine patients be 2008;63:148-158. identified interictally using a questionnaire? Neurology 2005;65:1419 –1422. 9. Mathew NT, Kailasam J, Seifert T. Clinical recognition of allodynia in migraine. Neurology. 16. Headache Classification Committee of the 2004;63: 848-852. International Headache Society (2013) The International Classification of Headache Disorders, 10. Weissman-Fogel I, Sprecher E, Granovsky Y, 3rd edition (beta version). Cephalalgia 33: 629–808. Yarnitsky D. Repeated noxious stimulation of the skin enhances cutaneous pain perception of migraine 17. Lipton RB, Bigal ME, Ashina S, et al. Cutaneous patients in-between attacks: Clinical evidence for allodynia in the migraine population. Ann Neurol. continuous sub-threshold increase in membrane 2008;63:148-158. ))))) USE IN DISCUSSION.. excitability of central trigeminovascular neurons. Pain. BOTH OF AVBOVE 2003;104:693-700. 18. Young WB, Richardson ES, Shukla P. Brush 11. BigalME,Ashina S,Burstein R,et al. Prevalence allodynia in hospitalized headache patients. and characteristics of allodynia in headache Headache 2005;45:999 –1003. sufferers:A population study. Neurology. 2008;70:1525-1533. 19. Aurora SK. Spectrum of illness: Understanding biological patterns and relationships in chronic 12. Cooke L, Eliasziw M, Becker WJ. Cutaneous migraine. Neurology. 2009;72:8–13. allodynia in transformed migraine patients. Headache. 2007;47:531-539. 20. Ashkenazi A, Silberstein S, Jakubowski M, Burstein R. Improved identification of allodynic 13. LoPinto C, Young WB, Ashkenazi A. Comparison migraine patients using a questionnaire. Cephalalgia. of dynamic (brush) and static (pressure) mechanical 2007;27: 325-329. allodynia in migraine. Cephalalgia.

References:

1. Burstein R, Yarnitsky D, Goor-Aryeh I, Ransil BJ, 4. Sessle BJ, Hu JW, Amano N, Zhong G. Convergence Bajwa ZH. An association between migraine and of cutaneous, tooth pulp, visceral, neck and muscle cutaneous allodynia. Ann Neurol. 2000;47:614-624. afferents onto nociceptive and non-nociceptive 1342 October 2009 neurones in trigeminal subnucleus caudalis (medullary dorsal horn) and its implications for referred pain. Pain 2. Baranauskas G, Nistri A. Sensitization of pain 1986;27:219 –235. pathways in the spinal cord: Cellular mechanisms. Prog Neurobiol. 1998;54:349-365. 5. Woolf CJ. Central sensitization: Implications for the Conflict of interest: There is no conflict of interest.. diagnosis and treatment of pain. Pain. Funding disclosure: Nil 3. Burstein R, Cutrer MF, Yarnitsky D. The development 2011;152:S2–S15. Author’s contribution: of cutaneous allodynia during a migraine attack: clinical Ghulam Shabbir; data analysis, manuscript writing, manuscript review evidence for the sequential recruitment of spinal and 6. Winkelstein BA. Mechanisms of central sensitization, Haris Majid Rajput; data collection, data analysis, manuscript writing, manuscript review supraspinal nociceptive neurons in migraine. Brain neuroimmunology and injury biomechanics in Zakir Jan; data analysis, manuscript writing, manuscript review 2000;123:1703–1709. persistent pain: Implications for musculoskeletal

PAKISTAN JOURNAL OF NEUROLOGICAL SCIENCES 08 VOL. 15 (1) JAN-MARCH 2020