Temporal artery ultrasonography for the diagnosis of giant cell arteritis: a case report.

Orofacial pain is a worldwide pain problem, with many patients unable to find appropriate diagnosis and treatment. Orofacial pain includes pain arising from the odontogenic and nonodontogenic structures in the head and neck region. Dental clinicians need to have a thorough knowledge and skill to diagnose, manage, and treat patients with odontogenic pain or refer patients for treatment of nonodontogenic pain to specialists such as orofacial pain specialists, neurologists, otolaryngologists, and rheumatologists. More often, dental practitioners diagnose patients with a temporomandibular disorder (TMD), and when treatment is ineffective, term it "atypical facial pain." The first requirement for effective treatment is an accurate diagnosis. Dental clinicians must be aware of giant cell arteritis (GCA), a chronic large-vessel vasculitis, primarily affecting adults over the age of 50 years, as it frequently mimics and is misdiagnosed as TMD. GCA is associated with loss of vision, and stroke and can be a life-threatening disorder. Therefore, diagnostic testing for GCA and differential diagnosis should be common knowledge in the armamentarium of all dental clinicians. Historically, temporal artery biopsy was considered the definitive diagnostic test for GCA. Temporal artery ultrasound (TAUSG), a safe and noninvasive imaging modality, has replaced the previous diagnostic gold standard for GCA, the temporal artery biopsy, owing to its enhanced diagnostic capabilities and safety profile. The present case report describes a patient with GCA, and the role TAUSG played in the diagnosis. Case report: A 72-year-old woman presented with left-sided facial pain, jaw claudication, dysesthesia of the tongue, and episodic loss of vision of 2 years' duration. She was diagnosed with and treated for a myriad of dental conditions including endodontia and temporomandibular joint therapy with no benefit. A thorough history and physical examination, combined with serologic analysis, led to the diagnosis of GCA and TAUSG, which confirmed the diagnosis. Conclusion: This report underscores the responsibility of differential diagnosis and early recognition of GCA facilitated by TAUSG in optimizing treatment outcomes as a viable, noninvasive diagnostic tool. (Quintessence Int 2024;55:336-343; doi: 10.3290/j.qi.b4938419).

Ultrasound-Guided Percutaneous Peripheral Nerve Stimulation of C2 Dorsal Root Ganglion for the Treatment of Refractory Atypical Facial Pain: A Technical Report and Case Series.

BACKGROUND: Chronic craniofacial pain can be difficult to manage clinically. This technical report documents the peripheral nerve stimulation of the C2 dorsal root ganglion as an effective modality to treat refractory atypical facial pain. MATERIALS AND METHODS: In this case series, three patients with chronic refractory atypical facial pain and p >50% pain relief following diagnostic C2 dorsal root ganglion blockade underwent ultrasound-guided percutaneous placement of a peripheral nerve stimulator adjacent to the C2 dorsal root ganglion. Patients were then observed clinically and monitored for improvement in symptoms and adverse events. RESULTS: Three patients underwent peripheral nerve stimulator placement. At follow-up, there were no reported adverse events, and all patients reported satisfactory improvement in pain. CONCLUSION: The neuromodulation of C2 dorsal root ganglion via ultrasound-guided percutaneously implanted peripheral nerve stimulator is a novel and potentially effective approach for the management of chronic refractory craniofacial pain.

Neuroimaging and artificial intelligence for assessment of chronic painful temporomandibular disorders-a comprehensive review.

Chronic Painful Temporomandibular Disorders (TMD) are challenging to diagnose and manage due to their complexity and lack of understanding of brain mechanism. In the past few decades' neural mechanisms of pain regulation and perception have been clarified by neuroimaging research. Advances in the neuroimaging have bridged the gap between brain activity and the subjective experience of pain. Neuroimaging has also made strides toward separating the neural mechanisms underlying the chronic painful TMD. Recently, Artificial Intelligence (AI) is transforming various sectors by automating tasks that previously required humans' intelligence to complete. AI has started to contribute to the recognition, assessment, and understanding of painful TMD. The application of AI and neuroimaging in understanding the pathophysiology and diagnosis of chronic painful TMD are still in its early stages. The objective of the present review is to identify the contemporary neuroimaging approaches such as structural, functional, and molecular techniques that have been used to investigate the brain of chronic painful TMD individuals. Furthermore, this review guides practitioners on relevant aspects of AI and how AI and neuroimaging methods can revolutionize our understanding on the mechanisms of painful TMD and aid in both diagnosis and management to enhance patient outcomes.

Assessing thickness and stiffness of superficial/deep masticatory muscles in orofacial pain: an ultrasound and shear wave elastography study.

INTRODUCTION: Sonoelastography has been increasingly used for non-invasive evaluation of the mechanical features of human tissues. The interplay between orofacial pain and regional muscle activity appears clinically paramount, although only few imaging studies have investigated this association. Using shear wave sonoelastography (SWS), this study ascertained whether orofacial pain induced alterations in the stiffness of superficial and deep masticatory muscles. METHODS: All participants were systematically evaluated for oral/facial-related conditions, including the area and intensity of pain. SWS was applied to measure the stiffness of the bilateral masseter, temporalis, and lateral pterygoid muscles. The association between orofacial pain and muscle stiffness/thickness was investigated using a generalized estimating equation for adjusting the influence of age, sex, laterality, and body mass index on muscle thickness/stiffness. RESULTS: A total of 98 participants were included in the present study: 48 asymptomatic controls, 13 patients with unilateral pain, and 37 patients with bilateral orofacial pain. The reliability, quantified by the intraclass correlation coefficient for muscle stiffness measurement, ranged from 0.745 to 0.893. Orofacial pain at the individual muscle level was significantly associated with masseter muscle stiffness. A trend of increased stiffness (p = 0.06) was also observed in relation to the painful side of the temporalis muscle. No significant correlation was identified between the numeric rating scales for pain and stiffness measurements. CONCLUSIONS: SWS provides reliable stiffness measurements for the superficial and deep masticatory muscles. The ipsilateral masseter and temporalis muscles might be stiffer than those on the side without orofacial pain. Future studies using the present sonoelasotography protocol can be designed to investigate the stiffness changes in the target muscles after interventions.

Shear wave sonoelastography (SWS) can reliably assess the stiffness of masticatory muscles.Orofacial pain, particularly affecting the ipsilateral masseter muscles, exhibited increased stiffness, with a similar trend observed in the temporalis muscle as revealed by SWS. However, the stiffness of the lateral pterygoid muscle appeared to remain unaffected.These findings establish a foundational framework for the objective and quantitative assessment of orofacial pain and indicate the potential utility of SWS as a tool for evaluating treatment outcomes.

Brain imaging signatures of neuropathic facial pain derived by artificial intelligence.

Advances in neuroimaging have permitted the non-invasive examination of the human brain in pain. However, a persisting challenge is in the objective differentiation of neuropathic facial pain subtypes, as diagnosis is based on patients' symptom descriptions. We use artificial intelligence (AI) models with neuroimaging data to distinguish subtypes of neuropathic facial pain and differentiate them from healthy controls. We conducted a retrospective analysis of diffusion tensor and T1-weighted imaging data using random forest and logistic regression AI models on 371 adults with trigeminal pain (265 classical trigeminal neuralgia (CTN), 106 trigeminal neuropathic pain (TNP)) and 108 healthy controls (HC). These models distinguished CTN from HC with up to 95% accuracy, and TNP from HC with up to 91% accuracy. Both classifiers identified gray and white matter-based predictive metrics (gray matter thickness, surface area, and volume; white matter diffusivity metrics) that significantly differed across groups. Classification of TNP and CTN did not show significant accuracy (51%) but highlighted two structures that differed between pain groups-the insula and orbitofrontal cortex. Our work demonstrates that AI models with brain imaging data alone can differentiate neuropathic facial pain subtypes from healthy data and identify regional structural indicates of pain.

Neuroimaging meta-analysis of brain mechanisms of the association between orofacial pain and mastication.

BACKGROUND: Temporomandibular disorders (TMD) are characterized by pain and impaired masticatory functions. The Integrated Pain Adaptation Model (IPAM) predicts that alterations in motor activity may be associated with increased pain in some individuals. The IPAM highlights the diversity of patients' responses to orofacial pain and suggests that such diversity is related to the sensorimotor network of the brain. It remains unclear whether the pattern of brain activation reflects the diversity of patients' responses underlying the association between mastication and orofacial pain. OBJECTIVE: This meta-analysis aims to compare the spatial pattern of brain activation, as the primary outcome of neuroimaging studies, between studies of mastication (i.e. Study 1: mastication of healthy adults) and studies of orofacial pain (i.e. Study 2: muscle pain in healthy adults and Study 3: noxious stimulation of the masticatory system in TMD patients). METHODS: Neuroimaging meta-analyses were conducted for two groups of studies: (a) mastication of healthy adults (Study 1, 10 studies) and (b) orofacial pain (7 studies), including muscle pain in healthy adults (Study 2) and noxious stimulation of the masticatory system in TMD patients (Study 3). Consistent loci of brain activation were synthesized using Activation Likelihood Estimation (ALE) with an initial cluster-forming threshold (p < .05) and a threshold of cluster size (p < .05, familywise error-corrected). RESULTS: The orofacial pain studies have shown consistent activation in pain-related regions, including the anterior cingulate cortex and the anterior insula (AIns). A conjunctional analysis of mastication and orofacial pain studies showed joint activation at the left AIns, the left primary motor cortex and the right primary somatosensory cortex. CONCLUSION: The meta-analytical evidence suggests that the AIns, as a key region in pain, interoception and salience processing, contributes to the pain-mastication association. These findings reveal an additional neural mechanism of the diversity of patients' responses underlying the association between mastication and orofacial pain.

Recommendations for Imaging of the Temporomandibular Joint. Position Statement from the American Academy of Oral and Maxillofacial Radiology and the American Academy of Orofacial Pain.

This position statement was developed by an ad hoc committee of the American Academy of Oral and Maxillofacial Radiology and the American Academy of Orofacial Pain. The committee reviewed the pertinent literature and drafted recommendations for imaging. This joint statement provides evidence-based recommendations and clinical guidance for applying appropriate diagnostic imaging to evaluate the temporomandibular joint (TMJ). This manuscript guides the design of TMJ imaging examinations, addresses in-office CBCT imaging, and provides timely evidence-based recommendations to evaluate the TMJ bony components, also addressing the use of MRI and other modalities to evaluate TMJ involvement in different pathologic conditions.

Functional MRI-Guided Motor Cortex and Deep Brain Stimulation for Intractable Facial Pain: A Novel, Personalized Approach in 1 Patient.

BACKGROUND: Facial neuropathic pain syndromes such as trigeminal neuralgia are debilitating disorders commonly managed by medications, vascular decompression, and/or ablative procedures. In trigeminal neuralgia cases unresponsive to these interventions, trigeminal deafferentation pain syndrome (TDPS) can emerge and remain refractory to any further attempts at these conventional therapies. Deep brain stimulation (DBS) and motor cortex stimulation are 2 neuromodulatory treatments that have demonstrated efficacy in small case series of TDPS yet remain largely underutilized. In addition, functional MRI (fMRI) is a tool that can help localize central processing of evoked stimuli such as mechanically triggered facial pain. In this study, we present a case report and operative technique in a patient with TDPS who underwent fMRI to guide the operative management and placement of dual targets in the sensory thalamus and motor cortex. OBJECTIVE: To evaluate the safety, efficacy, and outcome of a novel surgical approach for TDPS in a single patient. METHODS: The fMRI and operative technique of unilateral DBS targeting the ventroposteromedial nucleus of the thalamus and facial motor cortex stimulator placement through a single burr hole is illustrated as well as the patient's clinical outcome. RESULTS: In less than 1 year, the patient had near complete resolution of his facial pain with no postoperative complications. CONCLUSION: We present the first published case of successful treatment of TDPS using simultaneous DBS of the ventroposteromedial and motor cortex stimulation. fMRI can be used as an effective imaging modality to guide neuromodulation in this complex disorder.

Recommendations for imaging of the temporomandibular joint. Position statement from the American Academy of Oral and Maxillofacial Radiology and the American Academy of Orofacial Pain.

This position statement was developed by an ad hoc committee of the American Academy of Oral and Maxillofacial Radiology and the American Academy of Orofacial Pain. The committee reviewed pertinent literature and drafted recommendations for imaging. The statement provides evidence-based recommendations and clinical guidance to apply appropriate diagnostic imaging to evaluate the temporomandibular joint.

Temporomandibular joint involvement in children with juvenile idiopathic arthritis-Symptoms, clinical signs and radiographic findings.

BACKGROUND: Although many children with juvenile idiopathic arthritis (JIA) develop arthritis and deformity of the temporomandibular joint (TMJ), many go undetected. OBJECTIVE: This study investigates whether findings from patient history and clinical examination using the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) can be used to diagnose TMJ involvement. METHODS: As a part of the screening program, 59 consecutive JIA patients age 7-14 years underwent a clinical examination according to RDC/TMD including self-reported orofacial pain and pain related to jaw function, and cone beam computer tomography (CBCT). Data were obtained from the patient's medical charts. Patients were divided into two groups based on the presence or absence of TMJ deformities on CBCT. RESULTS: Self-reported TMJ symptoms before inclusion were reported by 52% of children with and 18% of children without TMJ deformities on CBCT (p = .020). On a group level, the maximum unassisted (mouth) opening (MUO) with and without pain was within the normal range, but children with TMJ deformities showed a significantly smaller MUO with pain (p = .035). A diagnosis of osteoarthritis and osteoarthrosis was more prevalent in children with TMJ deformities. CONCLUSION: Although there were few differences between children with and without radiographic TMJ deformities, self-reported previous TMJ symptoms and reduced MUO with pain could indicate the presence of TMJ involvement. However, radiographic examinations are needed to confirm TMJ involvement. Thus, this study indicates that the RDC/TMD protocol is a blunt tool when targeting TMJ involvement in JIA.

Imaging of Trigeminal Neuralgia and Other Facial Pain.

We review and illustrate the radiology of facial pain, emphasizing trigeminal neuralgia, relevant anatomy, current classification, concepts about etiology, and the role of imaging and its influence on the choice of treatment. We discuss glossopharyngeal neuralgia, other neuropathic causes of facial pain, postinflammatory and neoplastic causes, and nociceptive (end-organ) causes of facial pain, as well as referred otalgia. Other conditions that may present with facial pain, including trigeminal autonomic cephalgias and giant cell arteritis, are reviewed briefly. We discuss the elements of a comprehensive MR imaging protocol to enable detection of these diverse causes of facial pain.

Decompression of the Greater Occipital Nerve for Persistent Headache Attributed to Whiplash Accompanying Referred Facial Trigeminal Pain.

OBJECTIVE: Persistent headache attributed to whiplash (PHAW) is defined as a headache that occurs for the first time in close temporal relation to whiplash lasting more than 3 months. We investigated the results of decompression of the greater occipital nerve (GON) in patients with PHAW who presented with referred trigeminal facial pain caused by sensitization of the trigeminocervical complex) along with occipital headache. METHODS: A 1-year follow-up study of GON decompression was conducted in 7 patients with PHAW manifesting referred facial trigeminal pain. The degree of pain reduction was analyzed using the numeric rating scale (NRS-11) and percent pain relief before and 1 year after surgery. Success was defined by at least 50% reduction in pain measured via NRS-11. To assess the degree of subjective satisfaction, a 10-point Likert scale was used. Clinical characteristics of headache and facial pain and surgical findings were studied. RESULTS: GON decompression was effective in all 7 patients with PHAW manifesting referred trigeminal pain, with a percent pain relief of 83.06 ± 17.30. The pain had disappeared in 3 of 7 patients (42.9%) within 6 months and no further treatment was needed. Patients' assessment of subjective improvement based on a 10-point Likert scale was 7.23 ± 1.25. It was effective in both occipital and facial pain. CONCLUSIONS: Although chronic GON entrapment itself is an individual constitutional issue, postwhiplash inflammatory changes seem to trigger chronic occipital headaches in GON distribution and unexplained referred trigeminal pain caused by sensitization of the trigeminocervical complex.

Altered trigeminal pain processing on brainstem level in persistent idiopathic facial pain.

ABSTRACT: Persistent idiopathic facial pain (PIFP) is a poorly understood chronic pain syndrome of the face, formerly known as atypical facial pain. It is characterized by a constant painful sensation without neurological abnormalities and without clinically objectifiable cause. Similarities to neuropathic pain conditions have been discussed and are currently thought to be relevant for the pathophysiology of this disease. In this study, we aim to characterize the trigeminal pain processing in PIFP using functional magnetic resonance imaging of the brainstem. Twenty-five patients suffering from PIFP and 25 healthy controls underwent a standardized and well-established paradigm of painful stimulation of the trigeminal nerve using gaseous ammonia. Functional images were acquired within a 3T magnetic resonance imaging scanner using an optimized protocol for high-resolution echo planar brainstem imaging. Patients with PIFP show exclusively a stronger activation to painful stimulation in the spinal trigeminal nucleus when contrasted against healthy controls. Our data suggest that abnormal central pain processing plays a role in the pathophysiology of PIFP. An integration of these findings into neuropathic pain models might help to gain a better general understanding of the pathophysiology of PIFP.

A comparative clinical and radiographic study on patients with chronic facial pain with and without temporomandibular disorder presenting to an otolaryngology clinic.

Objective: Facial pain associated with temporomandibular disorder (TMD) is considered a component of Costen's syndrome. However, prior to the current study, no previous clinical and radiographic studies have addressed facial pain in patients with TMD. Methods: The study included 212 patients with chronic facial pain examined in an otolaryngology clinic. These were stratified into 132 patients with TMD and 80 patients without TMD. Clinical and radiographic findings were documented in both groups. Results: Forty-eight patients in the TMD group had normal endoscopic findings and clear CT scans and had their facial pain directly attributable to TMD. Conclusion: In patients presenting with facial pain, where nasal endoscopy reveals no abnormality, TMD should be specifically addressed, especially if CT scans of the paranasal sinuses are clear.

Trigeminal Neuralgia Secondary to Intracranial Neoplastic Lesions: a Case Series and Comprehensive Review.

It is known that intracranial tumors may trigger trigeminal neuralgia (TN) in some patients although the exact prevalence and occurrence is not completely defined yet. In the present study, we present a case series of patients with brain tumor and a clinical diagnosis of TN as the first and main manifestation of the disease. A retrospective analysis was performed involving patients diagnosed with brain tumor whose exclusive clinical feature our department focused on was TN. In addition, a review of all published cases was performed. From January 2017 to November 2018, 718 patients with brain tumor were admitted to our department, 17 of which suffered of TN, of which 8 patients presented with at least another neurologic symptom and 9 patients presented with TN alone, with typical symptoms of stubbing electric pain in 6 cases. In our series, we found that 2.3% of patients admitted for brain tumors had TN. In 0.8% of cases, TN was the main clinical symptom. The prevalence of tumor lesion in patients with facial neuropathic pain is not defined, but it is a well-known recognized initial symptom; however, early cerebral magnetic resonance imaging (MRI) is not yet strongly recommended in patients with newly diagnosed trigeminal neuralgia. The purpose of this article is, especially in unusual cases, to show that the application of such MR techniques and preoperative evaluation may contribute to diagnosis, indication, and surgery planning.

Comparison between Conventional Blind Injections and Ultrasound-Guided Injections of Botulinum Toxin Type A into the Masseter: A Clinical Trial.

The aim of the study was to propose a more efficient and safer botulinum toxin type A (BoNT-A) injection method for the masseter by comparing the conventional blind injection and a novel ultrasonography (US)-guided injection technique in a clinical trial. The 40 masseters from 20 healthy young Korean volunteers (10 males and 10 females with a mean age of 25.6 years) were included in this prospective clinical trial. The BoNT-A (24 U) was injected into the masseter of each volunteer using the conventional blind and US-guided injection techniques on the left and right sides, respectively, and analyzed by US and three-dimensional (3D) facial scanning. One case of PMB (paradoxical masseteric bulging) was observed on the side where a conventional blind injection was performed, which disappeared after the compensational injection. The reduction in the thickness of the masseter in the resting state differed significantly at 1 month after the injection between the conventional blind injection group and the US-guided injection group by 12.38 ± 7.59% and 17.98 ± 9.65%, respectively (t(19) = 3.059, p = 0.007). The reduction in the facial contour also differed significantly at 1 month after the injection between the conventional blind injection group and the US-guided injection group by 1.95 ± 0.74 mm and 2.22 ± 0.84 mm, respectively (t(19) = 2.908, p = 0.009). The results of the study showed that the US-guided injection method that considers the deep inferior tendon by visualizing the masseter can prevent the PMB that can occur during a blind injection, and is also more effective.

CT-Guided Percutaneous Trigeminal Tractotomy-Nucleotomy for Intractable Craniofacial Pain.

OBJECT: In this report, we aimed to analyze the outcome results of our patients who underwent percutaneous trigeminal tractotomy (TR) and nucleotomy (NC) procedures, which are defined as destructive procedures targeting the descending trigeminal tractus and nucleus caudalis of the spinal trigeminal nucleus, respectively, for intractable craniofacial pain. METHODS: The medical records of a total of 12 patients who underwent a total of 14 computed tomography (CT)-guided TR-NC procedures at our clinics between 2005 and 2017 were retrospectively reviewed. RESULTS: A significant increase in patients' performance status (p = 0.015) as well as a significant decrease in the VAS score (p < 0.001) were achieved. Grade I pain relief (VAS = 0, no pain) was established in 66.7% of the patients, whereas grade II pain relief was observed in the remaining patients. Two of the patients suffered from recurrent pain after the initial procedure. Both patients underwent a second trigeminal TR-NC procedure, and grade I pain relief was re-established. The mean VAS score at 3-month follow-up was 1.4 ± 1.1, whereas this score at 6-month follow-up was 2 ± 1.3. The trigeminal TR-NC procedure resulted in a significant decrease in patients' VAS scores at 3- and 6-month follow-up visits compared with preoperative VAS scores (p < 0.001). Transient ataxia was noted in only one patient (8.3%) early after the procedure. CONCLUSIONS: The results presented in the current study support the efficacy of the percutaneous CT-guided trigeminal TR-NC procedure in the management of intractable facial pain in selected patients. The use of CT guidance allows direct visualization of the target area, thereby enhancing the safety and success of the procedure.

The neuro-pathophysiology of temporomandibular disorders-related pain: a systematic review of structural and functional MRI studies.

Chronic pain surrounding the temporomandibular joints and masticatory muscles is often the primary chief complaint of patients with temporomandibular disorders (TMD) seeking treatment. Yet, the neuro-pathophysiological basis underlying it remains to be clarified. Neuroimaging techniques have provided a deeper understanding of what happens to brain structure and function in TMD patients with chronic pain. Therefore, we performed a systematic review of magnetic resonance imaging (MRI) studies investigating structural and functional brain alterations in TMD patients to further unravel the neurobiological underpinnings of TMD-related pain. Online databases (PubMed, EMBASE, and Web of Science) were searched up to August 3, 2019, as complemented by a hand search in reference lists. A total of 622 papers were initially identified after duplicates removed and 25 studies met inclusion criteria for this review. Notably, the variations of MRI techniques used and study design among included studies preclude a meta-analysis and we discussed the findings qualitatively according to the specific neural system or network the brain regions were involved in. Brain changes were found in pathways responsible for abnormal pain perception, including the classic trigemino-thalamo-cortical system and the lateral and medial pain systems. Dysfunction and maladaptive changes were also identified in the default mode network, the top-down antinociceptive periaqueductal gray-raphe magnus pathway, as well as the motor system. TMD patients displayed altered brain activations in response to both innocuous and painful stimuli compared with healthy controls. Additionally, evidence indicates that splint therapy can alleviate TMD-related symptoms by inducing functional brain changes. In summary, MRI research provides important novel insights into the altered neural manifestations underlying chronic pain in TMD.