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Chulhyoung Lyoo - One of the best experts on this subject based on the ideXlab platform.
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striatal dopamine loss and discriminative Sensory Dysfunction in parkinson s disease
Acta Neurologica Scandinavica, 2012Co-Authors: Chulhyoung LyooAbstract:Objectives Patients with Parkinson's disease (PD) have higher-order discriminative Sensory Dysfunction including prolonged somesthetic temporal discrimination threshold (sTDT). We studied the effect of striatal dopamine loss on the prolongation of sTDT and also studied the impact of prolonged sTDT values on the various parkinsonian motor deficits. Materials and Methods In 30 patients with PD, the severity of parkinsonian motor deficits was evaluated using the Unified Parkinson's Disease Rating Scale (UPDRS) motor scores during levodopa off and on periods. The UPDRS motor subscores were calculated, representing bradykinesia, rigidity, tremor, and axial motor deficits. During levodopa off and on periods, the sTDT value of each index finger was studied. Using [18F]-N-3-fluoropropyl-2-beta-carboxymethoxy-3-beta-(4-iodophenyl) nortropane (FPCIT) positron emission tomography studies, caudate and putaminal dopamine transporter uptake levels were measured. Multiple regression analysis covariated with age was used for statistical analysis. Results During the off period, the striatal FPCIT uptake levels had an impact on the sTDT values (P < 0.01). The sTDT values had an impact on the UPDRS subscores for axial motor deficits (P < 0.05), but had no impact on those for bradykinesia, rigidity, and tremor. The sTDT values as well as UPDRS total motor scores and all UPDRS subscores were improved by a single oral levodopa treatment. Conclusions Striatal dopamine deficiency and consequent basal ganglia Dysfunction may prolong sTDT, and higher-order discriminative Sensory Dysfunction seems to contribute in part to the development of axial motor deficits in patients with PD.
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Striatal dopamine loss and discriminative Sensory Dysfunction in Parkinson's disease.
Acta Neurologica Scandinavica, 2012Co-Authors: Chulhyoung LyooAbstract:Objectives Patients with Parkinson's disease (PD) have higher-order discriminative Sensory Dysfunction including prolonged somesthetic temporal discrimination threshold (sTDT). We studied the effect of striatal dopamine loss on the prolongation of sTDT and also studied the impact of prolonged sTDT values on the various parkinsonian motor deficits. Materials and Methods In 30 patients with PD, the severity of parkinsonian motor deficits was evaluated using the Unified Parkinson's Disease Rating Scale (UPDRS) motor scores during levodopa off and on periods. The UPDRS motor subscores were calculated, representing bradykinesia, rigidity, tremor, and axial motor deficits. During levodopa off and on periods, the sTDT value of each index finger was studied. Using [18F]-N-3-fluoropropyl-2-beta-carboxymethoxy-3-beta-(4-iodophenyl) nortropane (FPCIT) positron emission tomography studies, caudate and putaminal dopamine transporter uptake levels were measured. Multiple regression analysis covariated with age was used for statistical analysis. Results During the off period, the striatal FPCIT uptake levels had an impact on the sTDT values (P
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impaired finger dexterity in patients with parkinson s disease correlates with discriminative cutaneous Sensory Dysfunction
Movement Disorders, 2010Co-Authors: Chulhyoung Lyoo, Yun Ho ChoiAbstract:To study the influence of discriminative cutaneous Sensory Dysfunction on impaired finger dexterity in Parkinson's disease (PD), we evaluated 48 right-handed PD patients during a practically defined off-medication period and 24 healthy age-matched controls. With visual deprivation, a finger tapping task (FTT) was performed to assess the speed of simple repetitive finger movements and a coin rotation task (CRT) was used to assess finger dexterity. The tasks were performed with the right hand. We measured the somesthetic temporal discrimination threshold (sTDT) in the right index finger. The mean ± SD FTT score of the patient group was lower than that of the control group (24.0 ± 8.0 vs. 29.8 ± 7.8; P < 0.01). The patient group performed worse on the CRT than the control group (8.5 ± 3.5 vs. 12.6 ± 1.7; P < 0.001). The mean sTDT value of the patient group was longer than that of the control group (124.0 ± 44.8 vs. 78.1 ± 26.2 ms; P < 0.001). The CRT scores correlated with the sTDT values (Pearson's correlation coefficient = −0.43; P < 0.01), but not with the Unified Parkinson's Disease Rating Scale (UPDRS) finger bradykinesia scores or FTT scores. Multiple regression analysis showed that the sTDT values (parameter estimate = −0.03, SE = 0.01; P < 0.01), but not patient age, UPDRS finger bradykinesia score, or FTT score, affected the CRT score. Slowness of simple repetitive finger movements did not have a strong impact on the impaired manual dexterity of PD. Discriminative Sensory Dysfunction and consequent abnormal sensorimotor integration seem to be involved in the impaired finger dexterity of PD. © 2010 Movement Disorder Society.
Daniel C Javitt - One of the best experts on this subject based on the ideXlab platform.
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Auditory Sensory Dysfunction in Schizophrenia
2020Co-Authors: Esther F Rabinowicz, Gail Silipo, Robert S Goldman, Daniel C JavittAbstract:tractors were significantly elevated in patients in longterm residential care relative to all other groups (P,.001). The effect size (d) of the difference relative to controls was extremely large (SD, 1.95). Schizophrenic patients, even those with elevated tone-matching thresholds, showed no increased susceptibility to auditory distraction (P=.42). Deficits in tone-matching performance in subjects with chronic illness could not be attributed to medication status or level of symptoms. Conclusions: These findings suggest that Sensory processing Dysfunction in schizophrenia is particularly severe in a subgroup of patients who can be considered pooroutcome based on their need for long-term residential treatment. Furthermore, the absence of increased auditory distractibility argues against prefrontal Dysfunction as an origin for auditory Sensory imprecision in schizophrenia.
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a new dimension of Sensory Dysfunction stereopsis deficits in schizophrenia
Biological Psychiatry, 2006Co-Authors: Isaac Schechter, Daniel C Javitt, Pamela D Butler, Maria Jalbrzikowski, Roey Pasternak, Alice M SapersteinAbstract:Background Schizophrenia is a neurocognitive disorder with a wide range of cognitive and Sensory impairments. Early visual processing has been shown to be especially impaired. This article investigates the integrity of binocular depth perception (stereopsis) in schizophrenia. Methods Seventeen schizophrenia patients and 19 healthy control subjects were compared on the Graded Circles Stereo Test. Results of stereoacuity were compared between patients and control subjects using t test. Results Schizophrenia patients demonstrated significantly ( p = .006) reduced stereoacuity (mean = 142 arcseconds) versus control subjects (mean = 55 arcseconds). At the normative level for adults, patients performed below chance. Conclusions These findings demonstrate an impairment of binocular depth perception and further confirm deficits of early visual processing in schizophrenia. Findings are discussed in context of magnocellular/dorsal stream processing with implications for visual processing and cognitive deficits.
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auditory Sensory Dysfunction in schizophrenia imprecision or distractibility
Archives of General Psychiatry, 2000Co-Authors: Esther F Rabinowicz, Gail Silipo, Robert S Goldman, Daniel C JavittAbstract:Background Schizophrenia is associated with large effect-size deficits in auditory Sensory processing, as reflected in impaired delayed-tone matching performance. The deficit may reflect either impaired Sensory precision, which would be indicative of neural Dysfunction within auditory Sensory (temporal) regions, or of increased distractibility, which would be indicative of impaired prefrontal function. The present study evaluates susceptibility of schizophrenic subjects to same-modality distraction to determine whether patients fit a "bitemporal" or "prefrontal" model of Sensory Dysfunction. Methods Tone-matching ability was evaluated in 15 first-episode patients, 18 outpatients with chronic illness, and 21 patients in long-term residential care, relative to 32 nonpsychiatric controls of a similar age. A staircase procedure determined individual thresholds for attaining criterion level correct performance. Results Tone-matching thresholds in the absence of distractors were significantly elevated in patients in long-term residential care relative to all other groups ( P (d) of the difference relative to controls was extremely large (SD, 1.95). Schizophrenic patients, even those with elevated tone-matching thresholds, showed no increased susceptibility to auditory distraction ( P = .42). Deficits in tone-matching performance in subjects with chronic illness could not be attributed to medication status or level of symptoms. Conclusions These findings suggest that Sensory processing Dysfunction in schizophrenia is particularly severe in a subgroup of patients who can be considered poor-outcome based on their need for long-term residential treatment. Furthermore, the absence of increased auditory distractibility argues against prefrontal Dysfunction as an origin for auditory Sensory imprecision in schizophrenia.
Per Hansson - One of the best experts on this subject based on the ideXlab platform.
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painful traumatic peripheral partial nerve injury Sensory Dysfunction profiles comparing outcomes of bedside examination and quantitative Sensory testing
European Journal of Pain, 2008Co-Authors: Annsofie Leffler, Per HanssonAbstract:The primary aim of this retrospective study was to focusing on the relationship between individual outcomes of bedside examination (BE) and quantitative testing of somatoSensory functions (QST) in 32 patients with painful traumatic partial nerve injury. In addition, the potential presence of common Sensory Dysfunction denominators has been probed. Patients with a history of traumatic partial nerve injury and ongoing pain were included if pain was confined to the entire or part of the innervation territory of the severed nerve and a bedside titration of the neuronanatomical borders confirmed Sensory aberrations. An in-depth BE and QST was then performed in the most painful area. Categorization of normal and pathological outcome for both BE and QST was based on time honoured clinical decision-making using the healthy contralateral corresponding area as control. In patients with normal outcome or quantitative aberrations (i.e. hypo- or hyperesthesia) at BE and QST, the same individual outcome of touch sensation was reported by 48% of the patients, for cold in 54% and for warmth in 58%. The most common Dysfunction found at both BE and QST was hypoesthesia, however with no common denominators in somatoSensory Dysfunction. In conclusion, this study demonstrated that not infrequently the individual outcome of BE and the corresponding QST measure differed, most frequently for touch sensibility. This finding is of outmost importance when QST outcomes are used to corroborate results from BE in the diagnostic situation.
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Sensory Dysfunction in fibromyalgia patients with implications for pathogenic mechanisms
Pain, 1996Co-Authors: Eva Kosek, J Ekholm, Per HanssonAbstract:This study, addressing etiologic and pathogenic aspects of fibromyalgia (FM), aimed at examining whether Sensory abnormalities in FM patients are generalized or confined to areas with spontaneous pain. Ten female FM patients and 10 healthy, age-matched females participated. The patients were asked to rate the intensity of ongoing pain using a visual analogue scale (VAS) at the site of maximal pain, the homologous contralateral site and two homologous sites with no or minimal pain. Quantitative Sensory testing was performed for assessment of perception thresholds in these four sites. Von Frey filaments were used to test low-threshold mechanoreceptive function. Pressure pain sensitivity was assessed with a pressure algometer and thermal sensitivity with a Thermotest®. In addition the stimulus-response curve of pain intensity as a function of graded nociceptive heat stimulation was studied at the site of maximal pain and at the homologous contralateral site. FM patients had increased sensitivity to non-painful warmth (P < 0.01) over painful sites and a tendency to increased sensitivity to non-painful cold (P < 0.06) at all sites compared to controls, but there was no difference between groups regarding tactile perception thresholds. Compared to controls, patients demonstrated increased sensitivity to pressure pain (P < 0.001), cold pain (P < 0.001) and heat pain (P < 0.02) over all tested sites. The stimulus-response curve was parallely shifted to the left of the curve obtained from controls (P < 0.003). Intragroup comparisons showed that patients had increased sensitivity to pressure pain (P < 0.01) and light touch (P < 0.05) in the site of maximal pain compared to the homologous contralateral site. These findings could be explained in terms of sensitization of primary afferent pathways or as a Dysfunction of endogenous systems modulating afferent activity. However, the generalized increase in sensitivity found in FM patients was unrelated to spontaneous pain and thus most likely due to a central nervous system (CNS) Dysfunction. The additional hyperphenomena related to spontaneous pain are probably dependent on disinhibition/facilitation of nociceptive afferent input from normal (or ischemic) muscles.
P Binfield - One of the best experts on this subject based on the ideXlab platform.
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Sensory Dysfunction in the great toe in hallux valgus
Journal of Bone and Joint Surgery-british Volume, 2004Co-Authors: M L Herron, D J Beard, P BinfieldAbstract:Injury to the dorsomedial cutaneous nerve in the foot may occur after operations for hallux valgus. Pressure neuropathy before operation is also described but remains largely unexplored. We have investigated the incidence of Sensory deficit in the great toe before operating for hallux valgus and examined to what extent any deficit was related to the degree of angulation of the joint. Forty-three patients with a total of 61 great toes with hallux valgus presenting for consideration of surgical correction had their sensation tested in pre-designated zones using a five-filament set of Semmes-Weinstein monofilaments. These allowed good inter-observer reliability with an intra-class correlation coefficient of 0.84. Sensory symptoms were noted by only 21% of the patients, a measurable reduction in sensation by one monofilament grade or more was found in an additional 44%. No relationship was found between the degree of Sensory loss and the degree of angulation. Patients with symptomatic hallux valgus may have Sensory loss in the toe without being aware of it. Normal subjective sensation does not reliably predict normal Sensory function. Given the potentially high rates of nerve damage following operations for hallux valgus, we recommend objective Sensory testing as part of routine assessment before surgery.
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PREOPERATIVE Sensory Dysfunction OF THE GREAT TOE IN HALLUX VALGUS
2003Co-Authors: M L Herron, D J Beard, P BinfieldAbstract:Injury to the dorsomedial cutaneous nerve has been identified as a potentially frequent occurrence after hallux valgus surgery. The existence of pre-operative pressure neuropathy is also described but remains largely unexplored. This study was performed to investigate the incidence of pre-operative Sensory deficit in the hallux valgus toe, and to examine to what extent any deficit was related to the degree of joint angulation. A cohort of 43 patients (61 hallux toes) presenting for consideration of surgical correction had their sensation tested in pre-designated Sensory zones using a five-filament set of Semmes-Weinstein monofilaments. These allowed good inter-observer reliability with an ICC (intra-class correlation coefficient) of 0.84 overall. Whilst Sensory symptoms were self reported in only 21% of the feet, a measurable reduction in sensation by one monofilament grade or more was found in an additional 44% of the feet. No relationship was found between the degree of Sensory loss and degree of angulation. Patients with symptomatic hallux valgus may have Sensory loss of the toe despite not being aware of the deficit. Normal subjective sensation does not reliably predict normal Sensory function. Given the potentially high rates of intra-operative nerve damage in hallux surgery we recommend objective Sensory testing as part of routine pre-operative assessment.
Henrik Kehlet - One of the best experts on this subject based on the ideXlab platform.
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association between Sensory Dysfunction and pain 1 week after breast cancer surgery a psychophysical study
Acta Anaesthesiologica Scandinavica, 2016Co-Authors: Kenneth Geving Andersen, H M Duriaud, Eske Kvanner Aasvang, Henrik KehletAbstract:Background Breast cancer patients treated with axillary lymph node dissection (ALND) have a higher risk of both acute and persistent pain than those treated with sentinel lymph node biopsy (SLNB). This could be attributed to a higher risk of nerve injury with ALND. We hypothesized that (1) pain patients have more pronounced Sensory Dysfunction than pain-free patients, (2) ALND have more Sensory Dysfunction and pain than SLNB patients and (3) patients with preserved intercostobrachial nerve (ICBN) preservation have less Sensory Dysfunction compared to a sectioned ICBN. Methods Twenty-seven patients treated with ALND and 27 with SLNB examined with a standardized Quantitative Sensory Testing (QST) protocol, including Sensory mapping, mechanical and thermal thresholds, as well as recording intraoperative ICBN handling and pain status 1 week post-operative. Results The area of cold hypoaesthesia was significantly associated with movement-related pain (P = 0.004), with a similar tendency for warmth (P = 0.018) and brush (P = 0.030) hypoaesthesia areas. 14 (26%) of the patients had moderate/severe pain at rest and 13 (24%) during movement without differences between ALND and SLNB, but ALND was associated with more Sensory Dysfunction than SLNB. Patients with sectioned ICBN reported lower pain intensity than those with preserved ICBN (P = 0.005), but without differences in Sensory Dysfunction. Conclusion Pain was increased in patients having larger areas of hypoaesthesia and reduced in patients where ICBN-section was done. Sensory Dysfunction was related to extent of axillary surgery, but not with ICBN handling. Our data suggest that acute pain after breast cancer surgery may be related to nerve injury.
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Sensory testing in patients with postthoracotomy pain syndrome: Part 1: mirror-image Sensory Dysfunction.
The Clinical Journal of Pain, 2013Co-Authors: Mads U. Werner, Thomas K. Ringsted, Henrik Kehlet, Kim WildgaardAbstract:OBJECTIVES: Mirror-image Sensory Dysfunction (MISD) has not been systematically characterized in persistent postoperative pain. METHODS: The presence of MISD was evaluated with standardized stimuli, in preoperative patients scheduled for a thoracotomy (n = 14) and in patients with postthoracotomy pain syndrome [PTPS (n = 14)]. The primary outcome was investigation of the areas of Sensory Dysfunction, evaluated twice by dynamic Sensory mapping with metal rollers and a brush. RESULTS: In PTPS patients, Sensory Dysfunction was present on the surgical side, and in 12 of 14 patients MISD was demonstrated. The total areas of Sensory Dysfunction [median (interquartile range)] were: day 1, 500 (289 to 636) cm and 60 (0 to 379) cm on the surgical and nonsurgical side (P 0.5). The agreement between test-retest assessments was fair to excellent on the surgical side but poor on the nonsurgical side. None of the PTPS patients experienced mirror pain. DISCUSSION: MISD is a common finding in PTPS patients and deserves further study involving mechanism and clinical implications.
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Mirror-image Sensory Dysfunction in the post-thoracotomy pain syndrome
Scandinavian Journal of Pain, 2012Co-Authors: Mads U. Werner, Thomas K. Ringsted, Henrik Kehlet, Kim WildgaardAbstract:Abstract Background/aims Mirror-image Sensory Dysfunction (MISD) has been described in various medical conditions, but has not been systematically characterized following major surgery. Methods The presence of MISD was evaluated with standardized thermal and mechanical stimuli, in a group of preoperative patients scheduled for thoracotomy (n = 14) and in patients with post-thoracotomy pain syndrome (PTPS = 14). The primary outcome was areas with Sensory Dysfunction evaluated by dynamic Sensory mapping with metal-rollers and a brush. The test procedures were repeated after 2 weeks in PTPS-patients. Results The preoperative patients all had normal Sensory mapping. In all PTPS-patients Sensory Dysfunction on the surgical side was observed, while in 12/14 patients MISD was demonstrated. In 5/12 patients, the spatial distribution of MISD areas corresponded to the Sensory Dysfunction on the surgical side. The total areas of Sensory Dysfunction (median, [25–75% interquartile range]) were Day 1, on the surgical side 500 cm2 (289–636) and on the non-surgical side 60cm2 (0–379 [P<0.005]), and on Day 2, 355cm2 (266–697) and 81 cm2 (0–202379 [P< 0.0002]), respectively. Area of Sensory Dysfunction on the surgical side, respectively on the non- surgical side, did not differ significantly between Day 1 and Day 2 (P >0.5). Conclusions Mirror-image Sensory Dysfunction is a prevalent finding in PTPS-patients. The Sensory Dysfunction does not seem related to the underlying lung neoplasm per se. The study demonstrated a high day-to-day variability both in Sensory Dysfunction areas in the surgical side and in MISD-areas. The pathophysiological mechanisms behind MISD in chronic post-surgery pain deserve further study.
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persistent Sensory Dysfunction in pain free herniotomy
Acta Anaesthesiologica Scandinavica, 2010Co-Authors: Eske Kvanner Aasvang, Henrik KehletAbstract:Background: Persistent post-herniotomy pain may be a neuropathic pain state based on the finding of a persistent Sensory Dysfunction. However, detailed information on the normal distribution of Sensory function in pain-free post-herniotomy patients hinders identification of exact pathogenic mechanisms. Therefore, we aimed to establish normative data on Sensory function in pain-free patients >1 year after a groin herniotomy. Methods: Sensory thresholds were assessed in 40 pain-free patients by a standardized quantitative Sensory testing (QST). Secondary endpoints included comparison of Sensory function between the operated and the naive side, and correlation between Sensory function modalities. Results: QST showed that on the operated side, thermal data were normally distributed, but mechanical pressure and pinch thresholds were normalized only after log-transformation, and cold pain and pressure tolerance could not be normalized. Comparison of QST results revealed significant (P<0.01) cutaneous hypoesthesia/hyperalgesia, but also significant pressure hyperalgesia (P<0.01) and decreased pressure tolerance (P=0.02) on the operated vs. the naive side. Wind-up was seen in 6 (15%) but with a low pain intensity. Conclusion: Persistent Sensory Dysfunction is common in pain-free post-herniotomy patients. Future studies of Sensory function in persistent post-herniotomy pain should compare the findings to the present data in order to characterize individual patients and potentially identify subgroups, which may aid in allocation of patients to pharmacological or surgical treatment.
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Persistent Sensory Dysfunction in pain‐free herniotomy
Acta Anaesthesiologica Scandinavica, 2009Co-Authors: Eske Kvanner Aasvang, Henrik KehletAbstract:Background: Persistent post-herniotomy pain may be a neuropathic pain state based on the finding of a persistent Sensory Dysfunction. However, detailed information on the normal distribution of Sensory function in pain-free post-herniotomy patients hinders identification of exact pathogenic mechanisms. Therefore, we aimed to establish normative data on Sensory function in pain-free patients >1 year after a groin herniotomy. Methods: Sensory thresholds were assessed in 40 pain-free patients by a standardized quantitative Sensory testing (QST). Secondary endpoints included comparison of Sensory function between the operated and the naive side, and correlation between Sensory function modalities. Results: QST showed that on the operated side, thermal data were normally distributed, but mechanical pressure and pinch thresholds were normalized only after log-transformation, and cold pain and pressure tolerance could not be normalized. Comparison of QST results revealed significant (P
