Use of Temporary Percutaneous Peripheral Nerve Stimulation in an Oncologic Population: A Retrospective Review.

OBJECTIVES: Patients with an underlying cancer diagnosis may experience pain from many sources. Temporary, percutaneous peripheral nerve stimulation (PNS) is a minimally invasive procedure that can control pain in those who have failed conservative management. The purpose of this retrospective review is to show the use of PNS in managing pain in the oncologic setting. MATERIALS AND METHODS: Temporary, percutaneous PNS was placed under fluoroscopic or ultrasound guidance for 15 patients at a cancer pain facility. Cases were grouped by subtypes of cancer pain (ie, tumor-related, treatment-related, cancer-associated conditions, and cancer-independent). Before PNS, patients were refractory to medical management or previous interventional treatments. Patients were observed with routine clinic visits to monitor pain levels via visual analog scale (VAS) and quality-of-life measures. PNS was removed after the indicated 60-day treatment period. RESULTS: This retrospective review presents ten successful cases of oncologic-related pain treated with PNS. Patients with subtypes of pain that were tumor related, from cancer-associated conditions, and cancer independent all experienced a similar degree of pain relief. However, patients with cancer-treatment-related pain experienced the least analgesia from PNS. We also present six cases in which PNS did not provide adequate pain relief. CONCLUSION: PNS is an emerging technology in neuromodulation that may be useful in managing pain, especially in the oncologic population. Patients with cancer-related and non-cancer-related pain localized to a specific nerve distribution should be considered appropriate candidates for PNS. Further research is needed to optimize patient selection and indications for PNS in the population with cancer.

Dorsal root ganglion stimulation for chemotherapy-induced peripheral neuropathy.

BACKGROUND: Chemotherapy-induced peripheral neuropathy (CIPN) is a common consequence of cancer treatment that can be persistent and difficult to manage. Dorsal root ganglion stimulation (DRG-S) is a recently introduced but understudied treatment modality. This study explored the effect of DRG-S on pain and symptom burden associated with CIPN. METHODS: Patients with CIPN who underwent a DRG-S trial between January 2017 and August 2022 were identified through chart review after IRB approval was obtained. Demographic data, procedure details, pre-and postoperative scores, including the Numerical Rating Scale (NRS) and Edmonton Symptom Assessment System (ESAS), and duration of follow-up were recorded. Statistical analysis included descriptive statistics and paired t-tests to compare pre-and postoperative scores. RESULTS: Nine patients with an even mix of solid and hematologic malignancies underwent DRG-S trial and had a statistically significant decrease in NRS scores, with a mean reduction of 2.3 in their average pain (p = 0.014), 2.6 in worst pain (p = 0.023), and 2.1 in least pain (p = 0.018). Eight patients (88.9%) underwent permanent DRG-S implantation. Mean NRS scores remained lower than preoperative baselines through the first year of follow-up. Statistically significant reductions were noted at 3 months in average (2.1, p = 0.006) and least pain scores (1.9, p = 0.045), which further decreased after 6-12 months (average: 3.6, p = 0.049; least: 3.4, p = 0.023). Only the pain component of ESAS scores showed a significant reduction with DRG-S (2.0, p = 0.021). All patients endorsed improved sensation, 75% decreased their pain medication usage, and 37.5% reported complete pain relief by 2 years. CONCLUSION: Dorsal root ganglion stimulation can be an effective treatment for pain related to CIPN and deserves further investigation.

Peripheral Nerve Stimulation for Back Pain in Patients With Multiple Myeloma as Bridge Therapy to Radiation Treatment: A Case Series.

OBJECTIVES: Patients with spinal lesions or vertebral compression fractures from multiple myeloma often present with back pain that restricts their ability to lie flat and prevents them from undergoing cancer treatment. Temporary, percutaneous peripheral nerve stimulation (PNS) has been described for cancer pain secondary to oncologic surgery or neuropathy/radiculopathy from tumor invasion. The purpose of this case series is to show the use of PNS as an analgesic bridge therapy to treat myeloma-related back pain and allow patients to complete their course of radiation. MATERIALS AND METHODS: Temporary, percutaneous PNS was placed under fluoroscopic guidance for four patients with unremitting low back pain secondary to myelomatous spinal lesions. Before PNS, the patients had pain refractory to medical management and were unable to tolerate radiation mapping and treatment owing to low back pain while supine. Patients were followed with routine clinic visits to monitor pain and progression through cancer therapy. PNS was removed after approximately 60 days or after completion of radiation. RESULTS: This case series presents four successful cases of PNS to treat low back pain from myelomatous spinal lesions and associated vertebral compression fractures. PNS targeted the medial branch nerves to treat both nociceptive and neuropathic low back pain. All four patients successfully completed radiation therapy with PNS in place. CONCLUSIONS: PNS can effectively treat low back pain secondary to myeloma-related spinal lesions as a bridge therapy to radiation. The use of PNS is a promising option for back pain from other primary or metastatic tumors. Further research is needed into the use of PNS for cancer-related back pain.

Watchman Device Dislodgement Creating a Left Ventricular Outflow Tract Obstruction Requiring Emergency Cardiopulmonary Bypass.

Left atrial appendage (LAA) occlusion device implantation is becoming a more common alternative for stroke prophylaxis in patients with nonvalvular atrial fibrillation (AF) who are not able to tolerate long-term anticoagulation. Studies suggest the procedure has a 98.5% successful deployment rate (Boersma et al., 2016). We present a case where a rare but known complication involving dislodgement and migration of an implanted Watchman LAA occlusion device led to functional stenosis of the aortic valve creating a left ventricular outflow tract (LVOT) obstruction necessitating emergency cardiopulmonary bypass in the electrophysiology lab to safely retrieve the device.

Case report: Use of peripheral nerve stimulation for treatment of pain from vertebral plana fracture.

Vertebral plana fractures are a severe form of compression fractures that can cause significant morbidity due to incapacitating pain. Due to the flattening of the vertebrae in a plana fracture, accessing the vertebral body transpedicularly can be difficult, making traditional vertebral augmentation treatment dangerous. These injuries also typically occur in elderly patients with contraindications to invasive procedures. Peripheral nerve stimulation is a relatively new and minimally invasive treatment that uses electrical stimulation to inhibit pain signals from reaching the somatosensory cortex. Our case describes an 80 Year old female with multiple comorbidities and refractory pain due to a vertebral planar fracture successfully treated with a 60 day course of peripheral nerve stimulation as evidenced by over 50% reduction in symptoms and discontinuation of opioid pain medication use.

Palliative Nerve Block for Penile Calciphylaxis: A Case Report on Ultrasound-Guided Phenol Neurolysis.

A 78-year-old man with uncontrolled diabetes, heart failure, and hemodialysis-dependent end-stage renal disease presented with intractable penile pain secondary to calciphylaxis and necrosis of his glans penis. Given pain refractory to pharmacologic management and refusal of surgery, treatment entailed an ultrasound-guided dorsal penile nerve block with 5 mL of aqueous 4% phenol bilaterally. The patient reported immediate relief and died pain-free 3 months later. While phenol nerve blocks are increasingly uncommon due to local tissue toxicity, the precision of ultrasound leverages phenol's denaturing and axonal demyelinating properties to facilitate long-term targeted neurolysis to palliate chronic nonmalignant pain.

Microperimetry in age-related macular degeneration: association with macular morphology assessed by optical coherence tomography.

BACKGROUND/AIMS: Microperimetry is a technique that is increasingly used to assess visual function in age-related macular degeneration (AMD). In this study, we aimed to evaluate the relationship between retinal sensitivity measured with macular integrity assessment (MAIA) microperimetry and optical coherence tomography (OCT)-based macular morphology in AMD. METHODS: Prospective, cross-sectional study. All participants were imaged with colour fundus photographs used for AMD staging (Age-Related Eye Disease Study scale), spectral-domain OCT (Spectralis, Heidelberg, Germany) and swept-source OCT (Topcon, Japan). Threshold retinal sensitivity of the central 10° diameter circle was assessed with the full-threshold, 37-point protocol of the MAIA microperimetry device (Centervue, Italy). Univariable and multivariable multilevel mixed-effect linear regression models were used for analysis. RESULTS: We included 102 eyes with AMD and 46 control eyes. Multivariable analysis revealed that older age (p<0.0001), advanced AMD stage (p<0.0001) and reduced retinal thickness (p<0.0001) were associated with decreased mean retinal sensitivity. No associations were found between choroidal thickness and retinal sensitivity within the macula. Within the 10° diameter circle of the macula, the presence of ellipsoid disruption, subretinal fluid, atrophy and fibrosis, and outer retinal tubulation on OCT images was also associated with decreased retinal sensitivity (all p<0.05). CONCLUSIONS: There is an association between TRS as determined by MAIA microperimetry and several OCT structural parameters across various stages of AMD. This study highlights the relevance of microperimetry as a functional outcome measure for AMD.

Peripheral Changes Associated With Delayed Dark Adaptation in Age-related Macular Degeneration.

PURPOSE: To study the association between peripheral changes in age-related macular degeneration (AMD) and dark adaptation (DA). DESIGN: Prospective, cross-sectional study. METHODS: We recruited patients with AMD and a control group (>50 years) without any vitreoretinal disease. Ultra-widefield (UWF) pseudocolor and fundus autofluorescence (FAF) were obtained, and were assessed by 2 graders for the presence of several peripheral changes in perimacular, midperipheral, and far-peripheral zones. All participants were also imaged with 7-field color fundus photographs used for AMD staging (Age-Related Eye Disease Study classification system). Both eyes of study participants were tested with a dark adaptation (DA) extended protocol (20 minutes). Multilevel mixed-effect models (accounting for correlated outcomes between 2 eyes) were used for analyses. RESULTS: We included 128 eyes (n = 72 patients), 75% with AMD and the remainder controls. The presence of reticular pigmentary changes in the midperipheral (ß = 4.3, P = .012) and far-peripheral zones (ß = 8.4, P < .001) was associated with delayed rod-intercept times (RITs), even after adjusting for confounding factors. The presence, number, and extent of peripheral classic drusen did not show a similar association (P ≥ .148). The presence of a mottled decreased FAF pattern in the midperipheral zone was also associated with prolonged RITs (ß = 4.4, P = .031). CONCLUSION: Our results suggest an association between DA and the presence of peripheral reticular pigmentary changes, as well as the presence of a peripheral mottled decreased FAF pattern. This provides new insights on the clinical significance of peripheral changes in AMD, and their contribution to impairments on DA.

HEALTH CONDITIONS LINKED TO AGE-RELATED MACULAR DEGENERATION ASSOCIATED WITH DARK ADAPTATION.

PURPOSE: To determine the association between dark adaption (DA) and different health conditions linked with age-related macular degeneration (AMD). METHODS: Cross-sectional study, including patients with AMD and a control group. Age-related macular degeneration was graded according to the Age-Related Eye Disease Study (AREDS) classification. We obtained data on medical history, medications, and lifestyle. Dark adaption was assessed with the extended protocol (20 minutes) of AdaptDx (MacuLogix). For analyses, the right eye or the eye with more advanced AMD was selected. Multivariate linear and logistic regressions were performed, accounting for age and AMD stage. RESULTS: Seventy-eight subjects (75.6% AMD; 24.4% controls) were included. Multivariate assessments revealed that body mass index (BMI; ß = 0.30, P = 0.045), taking AREDS vitamins (ß = 5.51, P < 0.001), and family history of AMD (ß = 2.68, P = 0.039) were significantly associated with worse rod intercept times. Abnormal DA (rod intercept time ≥ 6.5 minutes) was significantly associated with family history of AMD (ß = 1.84, P = 0.006), taking AREDS supplements (ß = 1.67, P = 0.021) and alcohol intake (ß = 0.07, P = 0.017). CONCLUSION: Besides age and AMD stage, a higher body mass index, higher alcohol intake, and a family history of AMD seem to impair DA. In this cohort, the use of AREDS vitamins was also statistically linked with impaired DA, most likely because of an increased severity of disease in subjects taking them.

Novel grid combined with peripheral distortion correction for ultra-widefield image grading of age-related macular degeneration.

Purpose: Eyes with age-related macular degeneration (AMD) often harbor pathological changes in the retinal periphery and perimacular region. These extramacular changes have not been well classified, but may be phenotypically and functionally relevant. The purpose of this study was to demonstrate a novel grid to systematically study peripheral retinal abnormalities in AMD using geometric distortion-corrected ultra-widefield (UWF) imaging. Methods: This is a cross-sectional observational case series. Consecutive patients with AMD without any other coexisting vitreoretinal disease and control patients over age 50 without AMD or any other vitreoretinal disease were imaged using Optos 200 Tx. Captured 200° UWF images were corrected for peripheral geometric distortion using Optos transformation software. A newly developed grid to study perimacular and peripheral abnormalities in AMD was then projected onto the images. Results: Peripheral and perimacular changes such as drusen, retinal pigment epithelium changes and atrophy were found in patients with AMD. The presented grid in conjunction with geometric distortion-corrected UWF images allowed for systematic study of these peripheral changes in AMD. Conclusion: We present a novel grid to study peripheral and posterior pole changes in AMD. The grid is unique in that it adds a perimacular zone, which may be important in characterizing certain phenotypes in AMD. Our UWF images were corrected for geometric peripheral distortion to accurately reflect the anatomical dimensions of the retina. This grid offers a reliable and reproducible foundation for the exploration of peripheral retinal pathology associated with AMD.

Choroidal Changes Associated With Subretinal Drusenoid Deposits in Age-related Macular Degeneration Using Swept-source Optical Coherence Tomography.

PURPOSE: To compare choroidal vascular features of eyes with and without subretinal drusenoid deposits (SDD), using swept-source optical coherence tomography (SS OCT). DESIGN: Multicenter, cross-sectional study. METHODS: We prospectively recruited patients with intermediate age-related macular degeneration (AMD), without other vitreoretinal pathology. All participants underwent complete ophthalmic examination, color fundus photography (used for AMD staging), and spectral-domain OCT (to evaluate the presence of SDD). SS OCT was used to obtain automatic macular choroidal thickness (CT) maps, according to the Early Treatment Diabetic Retinopathy Study (ETDRS) sectors. For data analysis, we considered mean choroidal thickness as the arithmetic mean value of the 9 ETDRS sectors. SS OCT en face images of choroidal vasculature were also captured and converted to binary images. Choroidal vascular density (CVD) was calculated as a percent area occupied by choroidal vessels in a 6-mm-diameter submacular circular. Choroidal vessel volume was calculated by multiplying the average CVD by macular area and CT. Multilevel mixed linear models (to account for the inclusion of 2 eyes of same subject) were performed for analysis. RESULTS: We included 186 eyes (n = 118 subjects), 94 (50.5%) presenting SDD. Multiple regression analysis revealed that, controlling for age, eyes with SDD presented a statistically thinner mean CT (ß = -21.9, P = .006) and CT in all the individual ETDRS fields (ß ≤ -18.79, P ≤ .026). Mean choroidal vessel volume was also significantly reduced in eyes with SDD (ß = -0.003, P = .007). No significant associations were observed with mean CVD. CONCLUSION: In subjects with intermediate AMD, choroidal thickness and vessel volume are reduced in the presence of subretinal drusenoid deposits.