Burst or Conventional Peripheral Nerve Field Stimulation for Treatment of Neuropathic Facial Pain.

BACKGROUND: Trigeminal Neuropathic Pain (TNP) is a chronic facial pain syndrome caused by a lesion or disease affecting one or more branches of the trigeminal nerve. It may, for example, result from accidental injury to a branch of the trigeminal nerve by trauma or during surgery; it may also be idiopathic. TNP is typically constant, in contrast to most cases of the commoner trigeminal neuralgia. In some cases, pain may be refractory to pharmacological treatment. Peripheral nerve field stimulation is recognized as an effective minimally invasive surgical treatment option for this debilitating condition. To date, stimulation has used conventional tonic waveforms, which generate paraesthesia in the stimulated area. This is the first report of the use of paraesthesia-free burst pattern stimulation for TNP. METHODS: Seven patients were treated at the John Radcliffe Hospital for TNP from 2016 to 2018. Mean duration of preoperative symptoms was five years. All patients had exhausted pharmacological measures to limited effect. The initial three patients had tonic stimulation with the subsequent four having burst stimulation. Outcome was assessed using the numeric pain rating scale preoperatively and postoperatively at three and six months and one year. Side-effects and complications were also assessed as well as reduction in analgesic medication use. RESULTS: All patients achieved pain reduction of at least 50% at 6 months (range 50-100%, mean 81%, p = 0.0082). Those in the burst stimulation group were paraesthesia free. One patient developed a postoperative infection for which the system had to be removed and is awaiting reimplantation. There were no other complications in either group. CONCLUSION: Burst stimulation conferred similar pain control to tonic stimulation in our small cohort, and there were similar reductions in pain medication use. An additional benefit of burst stimulation is freedom from paraesthesia. Larger scale studies are needed to further evaluate burst stimulation and compare its efficacy with that of tonic stimulation.

Sphenopalatine Neuralgia: An Independent Neuralgia Entity. Pooled Analysis of a Case Series and Literature Review.

BACKGROUND: Structural damage or demyelization of the sphenopalatine ganglion may cause sphenopalatine neuralgia (SN). The current International Classification of Headache Disorders, third edition (ICHD-3) regards SN as a phenotype of cluster headache. Whether SN is an independent neuralgia entity has been debated for years. METHODS: This article presents a case series of SN, a review of all published cases, and a pooled data analysis of the identified cases. RESULTS: Seven patients were identified, with a median age at symptom onset of 59 years. Six cases were secondary to structural lesions surrounding the ipsilateral sphenopalatine ganglion, and all of them experienced significant clinical improvements after removing the primary causes. In the seventh patient, no evidence of underlying disease was found. The literature review showed that SN affected patients spanning a wide range of ages and both sexes. The clinical characteristics of SN might mimic cluster headache with the exception of cluster pattern and treatment response to oxygen. The typical duration of pain episodes in SN was several hours to several days; and in some cases, pain was persistent. Sixty-seven percent (59/88) of patients with SN had structural lesions around the sphenopalatine ganglion. CONCLUSION: SN could possibly be regarded as a different clinical entity from cluster headache. Based on our patients and literature review, SN can be categorized as idiopathic SN and secondary SN. Craniofacial structural lesions should be highly rating and taken into account when SN is suspected.

Fluoroscopic C-Arm and CT-Guided Selective Radiofrequency Ablation for Trigeminal and Glossopharyngeal Facial Pain Syndromes.

Objectives: Percutaneous radiofrequency ablation (RFA) of the gasserian ganglion through the foramen ovale and the glossopharyngeal nerve at the jugular foramen is a classical approach to treating trigeminal neuralgia (TN) and glossopharyngeal neuralgia (GPN), respectively. However, it can be technically challenging with serious complications. We have thus developed a novel technique utilizing C-arm and computerized tomography (CT) guidance to block TN and GPN. Our goals were to describe a three-dimensional image-based technique to improve patient comfort and to decrease procedural time associated with needle guidance. Study design: Consecutive procedures were reviewed. Setting: Academic hospital. Methods: Three patients with classical TN and GPN and 15 patients with atypical facial pain (AFP) were treated. Numeric rating scale (NRS) scores for pain at pretreatment and at one, three, and 12 months post-treatment were recorded. The primary clinical outcome (50% or more reduction in NRS) and secondary adverse clinical outcome (hematoma, facial numbness, etc.) were monitored. Results: We had a 100% technical success with respect to appropriate needle positioning. All three classical TN/GPN patients had both immediate and sustained pain relief. Complications were minimal. The 15 AFP patients, however, showed more variable results, with only five (33%) having sustained pain relief, while in the other 10 (67%) patients, we observed suboptimal response. Conclusions: We present a novel method and single-center experience with C-arm and CT-guided RFA of facial pain. Quick and accurate needle placement will help future advancements in the RFA algorithm so that more durable and consistent effects can be attained, reducing uncertainty with respect to needle placement as a confounder. The RFA procedure in our study had a satisfying effect for classical TN/GPN patients but was less successful for AFP patients, though it did mirror the results from previous studies. Limitations: This study is limited by its small sample size and nonrandomized design.

Diagnostic role of magnetic resonance imaging in assessing orofacial pain and paresthesia.

The aim of this study was to compare the efficacy of CT and MRI in evaluating orofacial pain and paresthesia. A total of 96 patients with orofacial pain and/or paresthesia were included in this study. The patients who underwent CT and/or MRI examinations were assessed, and the efficacy of CT and/or MRI examinations in detecting the causative disease of the orofacial pain and paresthesia was evaluated. Seventy (72.9%) of 96 patients underwent CT and/or MRI examinations. Whereas CT examinations detected 2 diseases (4.5%) in 44 tests, 13 diseases (37.1%) were detected in 35 MRI examinations. Seven (53.8%) of 13 diseases, which were detected by MRI, were found in elderly patients. A high percentage of patients, who claimed orofacial pain and paresthesia, have other diseases in their brain, especially in elderly patients, and MRI is more useful than CT for evaluating these patients.

Ultrasound-guided stellate ganglion block: safety and efficacy.

Cervical sympathetic and stellate ganglion blocks (SGB) provide a valuable diagnostic and therapeutic benefit to sympathetically maintained pain syndromes in the head, neck, and upper extremity. With the ongoing efforts to improve the safety of the procedure, the techniques for SGB have evolved over time, from the use of the standard blind technique, to fluoroscopy, and recently to the ultrasound (US)-guided approach. Over the past few years, there has been a growing interest in the ultrasound-guided technique and the many advantages that it might offer. Fluoroscopy is a reliable method for identifying bony surfaces, which facilitates identifying the C6 and C7 transverse processes. However, this is only a surrogate marker for the cervical sympathetic trunk. The ideal placement of the needle tip should be anterolateral to the longus colli muscle, deep to the prevertebral fascia (to avoid spread along the carotid sheath) but superficial to the fascia investing the longus colli muscle (to avoid injecting into the muscle substance). Identifying the correct fascial plane can be achieved with ultrasound guidance, thus facilitating the caudal spread of the injectate to reach the stellate ganglion at C7-T1 level, even if the needle is placed at C6 level. This allows for a more effective and precise sympathetic block with the use of a small injectate volume. Ultrasound-guided SGB may also improve the safety of the procedure by direct visualization of vascular structures (inferior thyroidal, cervical, vertebral, and carotid arteries) and soft tissue structures (thyroid, esophagus, and nerve roots). Accordingly, the risk of vascular and soft tissue injury may be minimized.

Ultrasound imaging of embedded shrapnel facilitates diagnosis and management of myofascial pain syndrome.

Trigger points can result from a variety of inciting events including muscle overuse, trauma, mechanical overload, and psychological stress. When the myofascial trigger points occur in cervical musculature, they have been known to cause headaches. Ultrasound imaging is being increasingly used for the diagnosis and interventional management of various painful conditions. A veteran was referred to the pain clinic for management of his severe headache following a gunshot wound to the neck with shrapnel embedded in the neck muscles a few years prior to presentation. He had no other comorbid conditions. Physical examination revealed a taut band in the neck. An ultrasound imaging of the neck over the taut band revealed the deformed shrapnel located within the levator scapulae muscle along with an associated trigger point in the same muscle. Ultrasound guided trigger point injection, followed by physical therapy resolved his symptoms. This is a unique report of embedded shrapnel and coexisting myofascial pain syndrome revealed by ultrasound imaging. The association between shrapnel and myofascial pain syndrome requires further investigation.

Two- and three-dimensional ultrasound imaging to facilitate detection and targeting of taut bands in myofascial pain syndrome.

INTRODUCTION: Ultrasound imaging has gained acceptance in pain management interventions. Features of myofascial pain syndrome have been explored using ultrasound imaging and elastography. There is a paucity of reports showing the benefit clinically. This report provides three-dimensional features of taut bands and highlights the advantages of using two-dimensional ultrasound imaging to improve targeting of taut bands in deeper locations. CASE REPORT: Fifty-eight-year-old man with pain and decreased range of motion of the right shoulder was referred for further management of pain above the scapula after having failed conservative management for myofascial pain syndrome. Three-dimensional ultrasound images provided evidence of aberrancy in the architecture of the muscle fascicles around the taut bands compared to the adjacent normal muscle tissue during serial sectioning of the accrued image. On two-dimensional ultrasound imaging over the palpated taut band, areas of hyperechogenicity were visualized in the trapezius and supraspinatus muscles. Subsequently, the patient received ultrasound-guided real-time lidocaine injections to the trigger points with successful resolution of symptoms. CONCLUSIONS: This is a successful demonstration of utility of ultrasound imaging of taut bands in the management of myofascial pain syndrome. Utility of this imaging modality in myofascial pain syndrome requires further clinical validation.

Length of the styloid process and anatomical implications for Eagle's syndrome.

The styloid process is a bony projection, located just anterior to the stylomastoid foramen, the normal length of which is approximately 20-25 mm. Elongation of the process may cause various clinical symptoms such as neck and cervicofacial pain, described as Eagle's syndrome. The present study aimed to determine the mean length of the styloid process on cadavers, panoramic radiographs, and dry skulls, and to investigate the incidence of the elongated styloid process, while assessing the elongation in relation to Eagle's syndrome. When the measurements from the panoramic radiographs were assessed, the mean length of the styloid processes in males and females on the right and left sides were found to be the following: 25.78 + or - 5.68 mm; 22.69 + or - 3.68 mm, 25.80 + or - 5.75 mm; and 22.75 + or - 3.65 mm, respectively. The males had greater styloid process lengths than the females, and the differences in length on both the right and left sides were statistically significant. Descriptive statistics and comparison results according to age groups were determined. There was no statistically significant difference between right or left styloid process lengths according to age groups. The mean length of the styloid process of the cadavers and dry bones was 22.54 + or - 4.24, and there was no significant difference between the right and left sides of the cadavers and dry bones. The incidence of the elongated styloid process was determined as 3.3%, and the elongations revealed a female dominance. The average length of the elongated styloid process was 36.06 + or - 6.12 mm, while the mean length of the styloid processes of the subjects reporting Eagle's syndrome was 40 + or - 4.72 mm. The results of this morphological study will assist clinicians in the diagnosis of Eagle's syndrome.

[Eagle syndrome: diagnostic imaging and therapy]. / Eagle Syndrom-- Bildgebende Diagnostik und Therapie.

In the case of clinical symptoms such as dysphagia, foreign-body sensation and chronic neck or facial pain close to the ear, an Eagle syndrome should be considered in the differential diagnosis. Rational diagnostics and therapy are elucidated on the basis of four case reports. Four patients presented in the outpatients clinic with chronic complaints on chewing and a foreign-body sensation in the tonsil region. Upon specific palpation below the mandibular angle, pain radiating into the ear region intensified. In all patients, local anaesthesia with lidocaine only led to a temporary remission of symptoms. Imaging diagnostics then performed initially included cranial survey radiograms according to Clementschitsch as well as in the lateral ray path and an OPTG. An axial spiral-CT was then performed using the thin-layer technique with subsequent 3-D reconstruction. Therapy consisted of elective resection with a lateral external incision from the retromandibular. From a symptomatic point of view, the cranial survey radiograms and the OPTG revealed hypertrophic styloid processes. The geometrically corrected addition of the axial CT images produced an absolute length of 51-58 mm. The 3-D reconstruction made it possible to visualise the exact spatial orientation of the styloid processes. An ossification of the stylohyoid ligament could definitely be ruled out on the basis of the imaging procedures. After resection of the megastyloid, the patients were completely free of symptoms. Spiral-CT with subsequent 3-D reconstruction is the method of choice for exact determination of the localisation and size of a megastyloid, while cranial survey radiograms according to Clementschitsch and in the lateral ray path or an OPTG can provide initial information. The therapy of choice is considered to be resection of the megastyloid, whereby an external lateral incision has proved effective.

Trigeminal neuralgia and other neuropathic pain syndromes of the head and face.

Trigeminal neuralgia is the most common craniofacial pain syndrome of neuropathic origin. Although the diagnosis remains based exclusively on history and symptomatology, modern diagnostic techniques, particularly high-resolution magnetic resonance imaging, provides valuable new insight into the pathophysiology of these cases with additional implications for therapeutic strategies. Other neuropathic syndromes affect the trigeminal nerve and warrant different treatments with varied rates of success. Rarely, neuralgias of other cranial nerves mimic trigeminal neuralgia. Finally, it is imperative to distinguish atypical facial pains from these neuropathic syndromes to avoid unsuccessful therapies.

Obliteration of fat planes by perineural spread of squamous cell carcinoma along the inferior alveolar nerve.

Squamous cell carcinoma showed perineural spread along the inferior alveolar nerve. Key CT features of this spread were foramen enlargement, resurfacing of tumor, and asymmetry of fat spaces.

[Study of facial neuralgia]. / Exploration d'une névralgie faciale.

So-called idiopathic, essential trigeminal neuralgia is characterised by typical severe pain in the territory of the trigeminal nerve or one of its divisions. This entity remains a diagnosis of exclusion after investigation by computerized tomography and/or magnetic resonance imaging of the path of the trigeminal nerve and its branches, to exclude any neoplastic, inflammatory, infectious or vascular process. Nevertheless, surgical exploration and now medical imaging have revealed in a large number of cases of "idiopathic" essential trigeminal neuralgia, compression of the trigeminal nerve as it emerges from the brainstem by a vascular loop.

Lower cranial nerve palsy produced by internal carotid artery dilatation. Report of two cases.

We report two cases of lower cranial nerve palsies (XII in case 1, IX-X-XII in case 2) associated with abnormalities of the internal carotid artery at the base of the skull. In case 1 a limited dissection of the carotid wall produced both paresis of the hypoglossal nerve and Horners syndrome by compression of the nerve trunk against the base of the skull and stretching of the periarterial sympathetic fibres respectively. In case 2 we speculate that a narrow angled kinking of the internal carotid artery may have damaged cranial nerves IX, X and XII by interfering with the blood supply to the nerve trunks. In both cases the outcome was favorable with almost complete regression of the initial symptoms. We conclude that the association between lower cranial nerve disturbances and internal carotid artery abnormalities is probably more common than was thought. We suggest that the pathogenesis of the damage to the cranial nerves may differ from one case to the next.

Etiology and treatment of idiopathic trigeminal and atypical facial neuralgias.

In a series of sixteen patients with idiopathic trigeminal neuralgia and twenty-one patients with atypical facial neuralgia, it was found that the painful phenomena associated with both disorders were, in nearly all instances, closely related to the presence of maxillary or mandibular bone cavities at previous tooth extraction sites. Standard oral surgical procedures for curettage of the cavities, together with administration of antibiotics, were employed in the successful treatment of both the trigeminal and atypical facial neuralgias, with complete pain remissions for periods varying from 2 months (for most recently treated cases) up to 9 years. The observations and results of this study suggest that dental and oral disorders may play a role in the genesis of trigeminal and atypical facial neuralgias.

The nasal arteries.

Thorough knowledge of the normal gross and radiographic anatomy of the nasal fossa is a prerequisite for correct interpretation of external carotid angiograms in patients with lesions in or adjacent to the nasal cavity. This report describes in detail the normal gross and angiographic vascular anatomy of the nasal fossa. The appearance of the sphenopalatine artery and nasal branches of the ethmoidal arteries in a variety of lesions that affect the nasal cavity, nasopharynx, and adjacent structures is also discussed. Typical changes in acute rhinitis, sinusitis, sphenopalatine neuralgia, vascular malformations, neoplasms, and benign bulky nasal masses are illustrated.

Routine tomography of the temporomandibular joint.

Routine lateral tomography of the temporomandibular joint has resulted in a three-fold increase in the detection of positive findings. The technique is easily accomplished, eliminates the problem of superimposition of unwanted structures, permits a true lateral view of the condyle and condylar fossa, and allows small articular surface abnormalities to be identified. Although the entrance skin dose to the patient's face in the beam is about two times greater per exposure than that for our previous conventional open and closed lateral views, we believe that the increased dose is reasonable and the resulting improved diagnostic accuracy outweighs this disadvantage.