Conversion disorder after implant of a spinal cord stimulator in a patient with a complex regional pain syndrome

Magnetic resonance imaging scans in patients with dorsal root ganglion stimulation

OBJECTIVE

Patients fitted with a neurostimulator face a greater need to undergo magnetic resonance imaging (MRI) scans. Given the lack of literature in this regard, this study aims to review our experience with MRI examinations on patients implanted with a dorsal root ganglion stimulation (DRG-S) system and their potential adverse events.

MATERIALS AND METHODS

We conducted a retrospective analysis of the prospective treatment documentation gathered from November 2011 to October 2020. We identified 259 MRI registrations for patients with an implanted neurostimulation system; the MRI examinations were performed using a 1.5 Tesla MRI system in accordance with a structured scheme.

RESULTS

Among the 259 MRI registrations identified in this study, 28 corresponded to patients with an implanted DRG-S system. In 2 cases, no MRI scan was performed, and thus, only 26 MRI examinations were evaluated in detail. The DRG-S device was approved for the requested MRI scans in only 2 of these 26 cases (7.7%). In addition, 2 minor adverse events (syncopal episode and connection problem) were identified, and only the second problem (3.8%) was related to neurostimulator operation.

CONCLUSIONS

Necessary MRI examinations in patients with DRG-S systems are rarely covered by the European CE/US Food and Drug Administration (CE/FDA) approval. Although the manufacturer recommendations are against the use of MRI in patients with implanted DRG-S in certain conditions, we performed these scans without causing injury to the patient or damaging the device. Given that data on safety are limited, MRIs should be conducted study related. We provide recommendations for the procedure that should be followed when an MRI is needed urgently.

New Onset Tinnitus after High-Frequency Spinal Cord Stimulator Implantation

The most common complications of spinal cord stimulation (SCS) therapy are generally related to surgical site infection and hardware malfunction. Less well understood are the adverse neurological effects of this therapy. We present the case of a patient who underwent placement of a Senza HF10 high-frequency spinal cord stimulator with subsequent development of tinnitus, vertigo, intermittent involuntary left facial twitches, and perioral numbness. These symptoms resolved following deactivation of her device. To further explore these less common neurologic complications of SCS therapy, a review of literature and a review of the U.S. Food and Drug Administration Manufacturer and User Facility Device Experience database are included. Further research and investigation in this area are needed so that clinicians and patients may have more complete knowledge and understanding of the potential treatment-limiting complications of spinal cord stimulation.

Conversion Disorder, Functional Neurological Symptom Disorder, and Chronic Pain: Comorbidity, Assessment, and Treatment

PURPOSE OF REVIEW

This paper examines the overlap of conversion disorder with chronic pain conditions, describes ways to assess for conversion disorder, and provides an overview of evidence-based treatments for conversion disorder and chronic pain, with a focus on conversion symptoms.

RECENT FINDINGS

Conversion disorder is a significant problem that warrants further study, given that there are not many well-established guidelines. Accurate and timely assessment should help move treatment in a more fruitful direction and avoid unnecessary medical interventions. Advances in neuroimaging may also help further our understanding of conversion disorder. Creating a supportive environment and a collaborative treatment relationship and improving understanding of conversion symptoms appear to help individuals diagnosed with conversion disorder engage in appropriate treatments. Novel uses of earlier treatments, such as hypnosis and psychodynamic approaches, could potentially be beneficial and require a more vigorous and systematic study. There are treatments that produce significant improvements in functioning and reduction of physical symptoms from conversion disorder even for very severe cases. Hypnotherapy, cognitive behavioral therapy, and inpatient multidisciplinary treatment with intensive physiotherapy for severe cases have the most evidence to support reduction of symptoms. Components of treatment for conversion disorder overlap with treatments for chronic pain and can be used together to produce therapeutic effects for both conditions. Treatment needs to be tailored for each individual's specific symptoms.

Complex regional pain syndrome-up-to-date

Complex regional pain syndrome (CRPS) was described for the first time in the 19th century by Silas Weir Mitchell. After the exclusion of other causes, CRPS is characterised by a typical clinical constellation of pain, sensory, autonomic, motor, or trophic symptoms which can no longer be explained by the initial trauma. These symptoms spread distally and are not limited to innervation territories. If CRPS is not improved in the acute phase and becomes chronic, the visible symptoms change throughout because of the changing pathophysiology; the pain, however, remains. The diagnosis is primarily clinical, although in complex cases further technical examination mainly for exclusion of alternative diagnoses is warranted. In the initial phase, the pathophysiology is dominated by a posttraumatic inflammatory reaction by the activation of the innate and adaptive immune system. In particular, without adequate treatment, central nociceptive sensitization, reorganisation, and implicit learning processes develop, whereas the inflammation moderates. The main symptoms then include movement disorders, alternating skin temperature, sensory loss, hyperalgesia, and body perception disturbances. Psychological factors such as posttraumatic stress or pain-related fear may impact the course and the treatability of CRPS. The treatment should be ideally adjusted to the pathophysiology. Pharmacological treatment maybe particularly effective in acute stages and includes steroids, bisphosphonates, and dimethylsulfoxide cream. Common anti-neuropathic pain drugs can be recommended empirically. Intravenous long-term ketamine administration has shown efficacy in randomised controlled trials, but its repeated application is demanding and has side effects. Important components of the treatment include physio- and occupational therapy including behavioural therapy (eg, graded exposure in vivo and graded motor imaging). If psychosocial comorbidities exist, patients should be appropriately treated and supported. Invasive methods should only be used in specialised centres and in carefully evaluated cases. Considering these fundamentals, CRPS often remains a chronic pain disorder but the devastating cases should become rare.

Spinal cord stimulator malfunction caused by radiofrequency neuroablation -A case report-

The implantation of spinal cord stimulators (SCSs) to treat chronic intractable pain is steadily increasing. And there is an increased likelihood of instances where other therapies or procedures are found to interfere with SCS function, which in turn may result in pain. Since SCS utilize electric impulses as well as magnets, special considerations need for patients with a SCS in situ who require these procedures. The present report describes a case where radiofrequency (RF) ablation of the third occipital nerve resulted in spontaneous activation of a cervical SCS device.

Streamlined classification of psychopathological hand disorders: A literature review

In the surgical hand clinic, psychopathological hand disorders can be sorted into one of the following four categories: (1) factitious wound creation and manipulation; (2) factitious edema; (3) psychopathological dystonias, and (4) psychopathological sensory abnormalities and psychopathological Complex Regional Pain Syndrome. This article introduces these four categories. Pertinent literature that includes descriptions of each category's syndromes and diseases, demographic and psychological profiles, differential diagnoses, and appropriate treatment recommendations is reviewed.