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Heli Forssell

Publications and source records attributed to Heli Forssell.

13 recordsLinked to original sources
PubMed2005

Neurophysiologic and quantitative sensory testing in the diagnosis of trigeminal neuropathy and neuropathic pain.

This study investigated the utility of neurophysiologic examination and thermal quantitative sensory testing (QST) in the diagnosis of trigeminal neuropathy and neuropathic pain. Fifty-eight patients (14 men), 34 with sensory deficit within the inferior alveolar nerve (IAN) and 24 within the lingual nerve (LN) distribution, were included. Twenty-six patients (45%) reported neuropathic pain. Patients underwent blink reflex (BR) test and thermal QST; sensory neurography was done to the IAN patients. Results of clinical sensory testing were available from the charts of 48 patients revealing abnormal findings in 77% of the IAN and in 94% of the LN patients. The BR test was abnormal in 41%, neurography in 96%, and QST in 91% of the IAN patients. In the LN group, BR was abnormal in 33%, and QST in 100% of the patients tested. Neurophysiologic tests and QST verified the subjective sensory alteration in all but 2 IAN patients, both with old injuries, and 4 LN patients who did not undergo QST. When abnormal, thermal QST showed elevation of warm and cold detection thresholds (hypo/anesthesia), hypoalgesia was less marked, and heat allodynia was only occasionally present. Contralateral thermal hypoesthesia after unilateral injury was found in 14 patients. It was associated with the occurrence of neuropathic pain (P=0.016). Axonal Abeta afferent damage was less severe in the IAN patients with pain than in those without pain (P=0.012). Neurophysiologic tests and thermal QST provide sensitive tools for accurate diagnosis of trigeminal neuropathy and study of pathophysiological features characteristic to human neuropathic pain.

Adult↗
PubMed2005

Searching for an assessment instrument to determine temporomandibular disorder pain profiles for the purposes of primary health care.

The objective was to study the utility of the graded chronic pain (GCP) scale of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) for the purpose of recognizing TMD pain profiles in primary health care. The GCP scale was used to gather data from 93 consecutive TMD patients seeking treatment in a primary health care setting. The GCP data were compared with pain profiles assessed by scales similar to the more complicated multidimensional pain inventory (MPI). The scales used were able to produce the similar 'dysfunctional profiles' in the TMD patients as the original MPI scale in the sample of chronic pain patients. Also, the original MPI profiles of 'adaptive copers' and 'interpersonally distressed' were produced with distinctive features. The GCP grades distributed almost identically among the subgroups produced by the pain profiles. Most grade I patients were classified as adaptive copers (82--86%), most grade II patients were interpersonally distressed (59%) and all except one of the grade III patients were classified as dysfunctional (83%). The results seem to support the main assumption of our study that the GCP scale is a simple screening tool suitable for identifying primary care TMD patients with various types of pain profiles.

Adaptation, Psychological↗
PubMed2004

Striatal dopamine D2 receptors in modulation of pain in humans: a review.

We review evidence indicating that the striatum and striatal dopamine D2 receptors are involved in the regulation of pain in humans. Painful stimulation produces an increase in regional cerebral blood flow in the human striatum. Pain is a common symptom in patients with nigrostriatal dopaminergic hypofunction. Positron emission tomography findings show that a low dopamine D2 receptor availability in the striatum of healthy subjects (indicating either a low density of dopamine D2 receptors or a high synaptic concentration of dopamine) is associated with a high cold pain threshold and a low capacity to recruit central pain inhibition by conditioning stimulation. Patients with chronic orofacial pain have higher dopamine D2 receptor availability than their age-matched controls. We propose that the striatal dopamine D2 receptor may be an important target for the diagnosis and treatment of chronic pain.

Animals↗
PubMed2004

Application of principles of evidence-based medicine to occlusal treatment for temporomandibular disorders: are there lessons to be learned?

Critical evaluation of treatment methods has become an important part of health care and will certainly have a major influence on decisions about acceptable treatment methods in the future. Evidence-based medicine (EBM) means the systematic, explicit, and judicious implementation of the best evidence in patient care. The most reliable sources of evidence are high-quality systematic reviews and randomized controlled trials (RCTs). A systematic EBM approach could be particularly useful in the treatment of temporomandibular disorders (TMD), where controversial and conflicting ideas about management are common. In this field, concerns about the lack of evidence are often expressed. This article aims to elucidate and discuss the application of EBM to the treatment of TMD, using the most controversial treatments (i.e., occlusal treatments) as an example. By applying the principles of EBM to TMD treatments, we wish to highlight some of the important issues that form the basis for high-quality care in this field. A systematic review of occlusal treatments (occlusal splints and occlusal adjustment) updated to January 2003 revealed 16 RCTs of occlusal splints and 4 of occlusal adjustment. The overall quality of the trials was fairly low. Recently, however, some high-quality RCTs of occlusal splints have been published. The most obvious methodologic shortcomings in published trials included problems in defining the patient population, inadequacies in performing randomization and blinding, problems in defining the therapies or appropriate control treatments, short follow-ups, and problems in monitoring patient compliance. Occlusal splint studies yielded equivocal results. Even in the most studied area, stabilization splints for myofascial face pain, the results do not justify definite conclusions about the efficacy of splint therapy. Their clinical effectiveness to relieve pain also seems modest when compared with pain treatment methods in general. None of the occlusal adjustment studies provided evidence supporting the use of this treatment method. The clinical implications of the findings and future perspectives are discussed.

Dentistry↗
PubMed2004

Venlafaxine in the treatment of atypical facial pain: a randomized controlled trial.

AIMS: To study in a randomized placebo-controlled design the efficacy of the antidepressant venlafaxine, a serotonin and a weak noradrenaline reuptake inhibitor, in the treatment of atypical facial pain (AFP). METHODS: The study was a randomized, double-blind, crossover comparison of venlafaxine and a placebo. It consisted of 2 treatment periods, each of 4 weeks' duration, separated by a 2-week washout period. Thirty patients suffering from chronic pain who had been diagnosed with AFP after a thorough clinical examination were recruited. Pain intensity and pain relief were registered at 6 visits. Anxiety, depression, and adverse effects were recorded. Venous blood samples were collected at the end of each treatment period for the determination of serum levels of venlafaxine and its metabolites. RESULTS: Twenty patients completed the trial. Eight patients discontinued because of adverse effects and 2 patients were excluded because of noncompliance. Two patients completed the trial but were excluded from the analysis because they experienced no pain at the baseline visit. There was no significant difference in pain intensity reduction between the maximum tolerated dose of venlafaxine (75 mg in most cases) and the placebo. Pain relief was significantly greater with venlafaxine than with the placebo treatment. Significantly more escape medication was consumed during the placebo period compared with the venlafaxine period. No significant correlation was found between the serum concentration of the drug and the response to treatment. Anxiety and depression scores did not differ between venlafaxine and placebo treatment. Adverse effects were equally common during both treatments. CONCLUSION: Venlafaxine was only modestly effective in the treatment of AFP.

Adult↗
PubMed2003

Striatal dopamine D1 and D2 receptors in burning mouth syndrome.

Animal studies have indicated that the nigrostriatal dopaminergic system is involved in central pain modulation. In a recent positron emission tomography (PET) study, we demonstrated presynaptic dysfunction of the nigrostriatal dopaminergic pathway in burning mouth syndrome, which is a chronic pain state. The objective of the present study was to examine striatal dopamine D1 and D2 receptors in these patients. We used 11C-NNC 756 and 11C-raclopride to study D1 and D2 receptor binding in a PET study in ten burning mouth patients and 11 healthy controls. Patients underwent a structured psychiatric evaluation and an electrophysiological test for the excitability of the blink reflex. The striatal uptake of 11C-NNC 756 did not differ between patients and controls. In a voxel-level analysis, the uptake of 11C-raclopride was statistically significantly higher in the left putamen in burning mouth patients (corrected P-value 0.038 at cluster-level). In the region of interest analysis, the D1/D2 ratio was 7.7% lower in the right putamen (0.64+/-0.04 vs. 0.69+/-0.04, P=0.01) and 6.4 % lower in the left putamen (0.65+/-0.05 vs. 0.70+/-0.05, P=0.05) when compared to controls. Increased 11C-raclopride uptake and the subsequent decrease in the D1/D2 ratio may indicate a decline in endogenous dopamine levels in the putamen in burning mouth patients.

Adult↗
PubMed2003

Altered dopamine D2 receptor binding in atypical facial pain.

Animal studies suggest that the dopaminergic system plays a role in central pain modulation. We have previously demonstrated with positron emission tomography (PET) that striatal dopaminergic hypofunction may be involved in the burning mouth syndrome. The aim of the present study was to evaluate the nigrostriatal dopaminergic system in patients with atypical facial pain using PET. In seven patients with atypical facial pain, striatal presynaptic dopaminergic function was assessed with [18F]FDOPA and dopamine D1 and D2 receptor availabilities with [11C]NNC 756 and [11C]raclopride, respectively. The results were compared with those of healthy controls. A quantitative region-of-interest analysis showed that the uptakes of [18F]FDOPA and [11C]NNC 756 did not differ between patients and controls. There was a tendency of increased D2 receptor availability in the left putamen (P=0.056), and the D1/D2 ratio in the putamen was decreased bilaterally by 7.7% (P=0.002) in patients when compared to controls. In a voxel-based analysis, the uptake of [11C]raclopride was increased in the left putamen (P=0.025). In conclusion, the increase in D2 receptor availability in the left putamen and the decrease in D1/D2 ratio imply that alterations in the striatal dopaminergic system as evaluated by PET may be involved in chronic orofacial pain conditions.

Aged↗
PubMed2003

Interventions for the treatment of burning mouth syndrome: a systematic review.

AIMS: To carry out a systematic review of previous studies to determine the effectiveness of any intervention vs placebo for relief of symptoms and improvement in quality of life of patients with burning mouth syndrome (BMS) and to assess the quality of the studies. METHODS: Electronic databases, conference proceedings, and bibliographies of identified publications were searched (up to September 2001) to identify relevant literature, irrespective of language of publication. Randomized controlled trials and controlled clinical trials of interventions used for the treatment of BMS in comparison to a placebo were included. The primary outcome was relief of burning/discomfort. The screening of studies, validity assessment, and data extraction were undertaken independently and in duplicate. Since statistical pooling of data was inappropriate, a qualitative assessment was undertaken. RESULTS: Seven trials, evaluating antidepressants, cognitive behavioral therapy, analgesics, hormone replacement therapy, and vitamin complexes, met the inclusion criteria. None of the trials was able to provide conclusive evidence of effectiveness. However, cognitive behavioral therapy may be beneficial in reducing the intensity of the symptoms. CONCLUSION: Given that the research evidence is, as yet, unable to provide clear, conclusive evidence of an effective intervention, clinicians need to provide support and understanding when dealing with BMS sufferers. Psychological interventions that help patients to cope with symptoms may be of some use, but promising and new approaches to treatment still need to be evaluated in good-quality randomized controlled trials.

Analgesics, Non-Narcotic↗
PubMed2002

Sensory dysfunction in burning mouth syndrome.

Our preliminary observations on a small group of burning mouth syndrome (BMS) patients indicated a change in the non-nociceptive, tactile sensory function in BMS and provided evidence for the hypothesis of a neuropathic etiology of BMS. In the present clinical study on a group of 52 BMS patients, we used quantitative sensory tests (QST) in addition to the blink reflex (BR) recordings in order to gain further insight into the neural mechanisms of BMS pain. Based on electrophysiologic findings, the BMS patients could be grouped into four different categories: (1) The results of the BR were suggestive of brainstem pathology or peripheral trigeminal neuropathy in ten (19%) patients. In most of the cases, the abnormalities in the BR seemed to represent subclinical changes of the trigeminal system. (2) Increased excitability of the BR was found in the form of deficient habituation of the R2 component of the BR in 11 (21%) of the patients. Two of these patients also showed signs of warm allodynia in QST. (3) One or more of the sensory thresholds were abnormal indicating thin fiber dysfunction in altogether 35 patients (76%) out of the 46 tested with QST. Thirty-three of these patients showed signs of hypoesthesia. (4) There were only five patients with normal findings in both tests. The present findings with strong evidence for neuropathic background in BMS will hopefully provide insights for new therapeutic strategies.

Adult↗
PubMed2001

Role of the dopaminergic system in chronic pain -- a fluorodopa-PET study.

Recent data from animal experiments suggest an important role for the basal ganglia in the processing and sensorimotor gating of nociceptive information. However, very little is known about their possible participation in human pain. Because of our previous finding of increased excitability of the blink reflex (a brainstem reflex under dopaminergic inhibitory control) in some burning mouth syndrome (BMS) patients, we have studied the dopaminergic function of the striatum (putamen and caudatus) of BMS patients with positron emission tomography (PET). 6-[(18)F]fluorodopa (FDOPA) PET scans were done on ten BMS patients and 14 healthy control subjects. The presynaptic dopaminergic function was significantly decreased in the right putamen (20%, P=0.04) of the BMS patients compared to control subjects. On the left side, the FDOPA uptake was decreased by 17% (P=0.08). The mean FDOPA uptake was not significantly changed in the caudate nucleus of the patients. The finding of decreased striatal FDOPA uptake in the putamen supports our previous neurophysiological observations indicating decreased dopaminergic inhibition in BMS patients. The present result provides direct evidence of the involvement of the nigrostriatal dopaminergic system in pain for the first time in a clinical pain condition.

Adult↗
PubMed1999

Occlusal treatments in temporomandibular disorders: a qualitative systematic review of randomized controlled trials.

Occlusal treatments (occlusal splints and occlusal adjustment) are controversial but widely used treatment methods for temporomandibular disorders (TMD). To investigate whether studies are in agreement with current clinical practices, a systematic review of randomized controlled trials (RCTs) of occlusal treatment studies from the period 1966 to March 1999 was undertaken. Eighteen studies met the inclusion criteria, 14 on splint therapy, and 4 on occlusal adjustment. The trials were scored using the quality scale presented by Antczak et al., 1986a (A.A. Antczak, J. Tang, T.C. Chalmers, Quality assessment of randomized control trials in dental research. I. Methods, J. Periodontal Res. 1986a;21:305-314). The overall quality of the trials was fairly low, the mean quality score was 0.43/1.00 (range 0.12-0.78). The most obvious methodological shortcomings were inadequate blinding, small sample sizes, short follow-up times, great diversity of outcome measures and numerous control treatments, some of unknown effectiveness. Splint therapy was found superior to 3, and comparable to 12 control treatments, and superior or comparable to 4 passive controls, respectively. Occlusal adjustment was found comparable to 2 and inferior to one control treatment and comparable to passive control in one study. Because of the methodological problems, only suggestive conclusions can be drawn. The use of occlusal splints may be of some benefit in the treatment of TMD. Evidence for the use of occlusal adjustment is lacking. There is an obvious need for well designed controlled studies to analyse the current clinical practices.

Humans↗
PubMed1997

Abnormalities of the blink reflex in burning mouth syndrome.

To our knowledge, this is the first report on pain-related abnormalities of the eye blink reflex (BR) in a clinical pain patient population. The objective of this study was to evaluate the possible neuropathic mechanisms underlying the burning mouth syndrome (BMS), by means of objective electrophysiological examination of the trigemino-facial system. We studied the BR with stimulation of the supraorbital nerve (SON) with particular emphasis on the occurrence of the pain-related ultralate R3 components, and the habituation response of the R2 components. The subjects consisted of eleven BMS patients and 10 healthy control subjects. All patients underwent thorough clinical oral and neurological examinations. The motor function of the trigeminal nerve was assessed with a jaw reflex recording, and a needle-EMG examination of the facial and masticatory muscles was performed in the patients with abnormalities in the BR recordings. The jaw reflexes, the latencies of the BR components, and the needle-EMG examinations were normal in all patients. As a group, the BMS patients had statistically significantly higher stimulus thresholds for the tactile R 1 components of the BR compared with the control subjects. With non-noxious stimulation, the BMS patients showed more frequently pain-related R3 components (11/22 SONs) compared with the controls (3/20 SONs). In addition, four BMS patients had abnormal habituation of the R2 components. In two of these patients, the findings were segmental (i.e., unilateral), coinciding with the side of the subjective BM symptoms. The abnormalities of the BR tests appeared to be related to longer disease duration. Our results suggest a possible pathologic involvement of the nervous system in chronic BMS.

Aged↗