Subdural Spread of Local Anesthetic Mimicking Cerebrovascular Accident: A Case Report of Horner's Syndrome, Upper Limb Paresthesia, and Motor Weakness After Thoracic Epidural Analgesia.

A 53-year-old woman underwent a thoracic epidural placement for a scheduled laparotomy. Postoperatively the patient had no appreciable epidural level after multiple epidural boluses and was noted to be severely hypotensive with right upper extremity weakness and numbness. She subsequently developed right-sided Horner's syndrome with worsening right upper extremity weakness and decreased sensation from C6 to T1. She regained full motor and sensory function in her right upper extremity with epidural removal. This unusual case raises awareness of the variability in the presentation of subdural spread and provides an example of an epidural complication that can mimic a cerebrovascular accident (CVA).

Evaluation of fibromyalgia frequency and quality of life in Notalgia paresthetica patients.

Based on the presence of chronic pain and the potential use of common treatment agents in Notalgia Paresthetica (NP) and Fibromyalgia Syndrome (FMS) for improvement, we aimed to investigate the frequency of FMS symptoms in NP patients and its impact on quality of life. This study is a case control cohort study including 26 patients diagnosed with NP and a total of 26 controls matched for age and gender. The 2016 revised fibromyalgia diagnostic criteria by the American College of Rheumatology (ACR) were used to inquire about FMS diagnosis criteria in the study. According to the 2016 ACR revised FMS diagnostic criteria, the frequency of FMS was significantly higher in the patient group (n = 9, 34.6%) compared to the control group (n = 2, 7.7%) (p = 0.042). The Wide Pain Index (WPI) score in the control group was 2.00 (3.25), while in the patient group, it was 4.00 (8.00), with a statistically significant difference between them (p < 0.035). Furthermore, significant statistical differences were found between the two groups in terms of Symptom Severity Scale (SSS), Fibromyalgia Score (FS), and FIQ (p < 0.035, p < 0.001, p < 0.001, respectively). In NP patients with accompanying FMS, Dermatology Life Quality Index was significantly more affected compared to those without FMS (p = 0.025). In conclusion, we recommend that NP patients be questioned about FMS, which is characterized by generalized pain, as well as regional neuropathic symptoms. Treatment success can be enhanced by using common agents in the treatment choice for accompanying FMS.

Case report: Bilateral facial palsy with paresthesias and positive anti-GT1a antibodies.

Bilateral facial palsy with paresthesia (FDP) is a rare variant of GBS, characterized by simultaneous bilateral facial palsy and paresthesia of the distal limbs. Mounting evidence indicates that the presence of anti-GT1a IgG has a pathogenic role as an effector molecule in the development of cranial nerve palsies in certain patients with GBS, whereas anti-GT1a antibody is rarely presented positive in FDP. Here, we report the case of a 33-year-old male diagnosed with FDP presented with acute onset of bilateral facial palsy and slight paresthesias at the feet as the only neurological manifestation. An antecedent infection with no identifiable reason for the fever or skin eruptions was noted in the patient. He also exhibited cerebrospinal fluid albuminocytologic dissociation and abnormal nerve conduction studies. Notably, the testing of specific serum anti-gangliosides showed positive anti-GT1a IgG/IgM Ab. The patient responded well to intravenous immunoglobulin therapy. This case brings awareness to a rare variant of GBS, and provides the first indication that anti-GT1a antibodies play a causative role in the development of FDP. The case also suggests that prompt management with IVIG should be implemented if FDP is diagnosed.

Nitrous Oxide-induced Myeloneuropathy Due to Recreational Abuse.

BACKGROUND: The recreational use of nitrous oxide (N2O) has increased in recent years with a noticeable surge in the incidence of nitrous oxide-related myeloneuropathy. OBJECTIVES: To raise awareness of increasing myeloneuropathy due to recreational nitrous oxide misuse in Israel. METHODS: We conducted a case series documenting the clinical and investigative features of eight patients presenting with nitrous oxide-induced myeloneuropathy who were admitted to our departments. RESULTS: Paresthesia was the chief complaint in all patients, with sensory gait ataxia being a common feature, which was often accompanied by Romberg's sign and mild lower limb weakness. Vitamin B12 levels were below the normal range in seven patients, accompanied by elevated homocysteine and methylmalonic acid levels. Magnetic resonance imaging scans revealed hyperintense signals in the dorsal columns of the cervical spine. All patients improved following vitamin B12 injections. CONCLUSIONS: Enhancing awareness, prompting the use of appropriate investigations, and advocating for timely treatment are needed to overcome the risks associated with nitrous oxide misuse.

Relationships between the global symptom score and electrophysiological findings after surgical release for carpal tunnel syndrome: Indications and outcomes.

PURPOSE: Regarding surgical indications for carpal tunnel syndrome (CTS), the hypothesis that the recovery processes of subjective symptoms differ among pain, sensory, and motor symptoms and correlate with recovery in objective nerve conduction studies was examined in the present study. METHODS: The global symptom score (GSS) is a method used to assess clinical outcomes and covers subjective symptoms, including pain (pain and nocturnal awakening), sensory (numbness and paresthesia), and motor (weakness/clumsiness) symptoms. The relationships between long-term changes in GSS and recovery in nerve conduction studies were investigated. RESULTS: Forty patients (40 hands) were included (mean age 65 years; 80% female; 68% with moderate CTS: sensory nerve conduction velocity < 45 m/s and motor nerve distal latency > 4.5 ms). Pain and nocturnal awakening rapidly subsided within 1 month after surgery and did not recur in the long term (median 5.6 years). Paresthesia significantly decreased 3 months after surgery and in the long term thereafter. Weakness/clumsiness significantly decreased at 1 year. Sensory nerve distal latency, conduction velocity, and amplitude significantly improved 3 months and 1 year after surgery, and correlated with nocturnal awakening in the short term (3 months) in moderate CTS cases. The patient satisfaction rate was 91%. CONCLUSION: Rapid recovery was observed in pain and nocturnal awakening, of which nocturnal awakening correlated with the recovery of sensory nerve conduction velocity. Patients with pain symptoms due to moderate CTS may benefit from surgical release.

The role of tuning fork in the evaluation of musculoskeletal disorders and pallesthesia: A scoping review.

BACKGROUND: Musculoskeletal and neurological conditions disorders are important conditions that need to be assessed in clinical practice. The tuning fork (TF) has been proposed as a practical tool to investigate suspected fractures and for the evaluation of pallesthesia in subjects with peripheral neuropathy. OBJECTIVE: the aim of this study is to define whether the tuning fork can be useful in the clinical evaluation of patients with musculoskeletal disorders and deep somatosensory dysfunctions. METHODS: This scoping review was performed in accordance with Joanna Briggs Institute. MEDLINE, Cochrane Library, PEDro, CINAHL, Web of Science, UpToDate, Scopus Database were consulted. RESULTS: 14 studies were included in the final analysis. Nine studies regard the use of tuning fork to detect fractures. If the tuning fork was used with a stethoscope, the test reached a high sensitivity ranging between 83% and 94%. Five studies investigated the tool to evaluate pallesthesia dysfunctions among which possible differences between biceps femoris strain and simple clinical rules for detecting peripheral neuropathy. CONCLUSION: The 128 Hz tuning fork could be potentially useful to detect some type of traumatic fractures. The Rydel-Seiffer tuning fork appears to be a useful tool for assessing potential nerve conduction deficits in the evaluation of pallesthesia.

A systematic review of procedural modalities in the treatment of notalgia paresthetica.

BACKGROUND: Notalgia paresthetica (NP) is a rare condition characterized by localized pain and pruritus of the upper back, associated with a distinct area of hyperpigmentation. Given the lack of standardized treatment and the uncertain efficacy of available options, applying procedural methods is of growing interest in treating NP. AIMS: We sought to comprehensively evaluate the role of procedural treatments for NP. METHODS: We systematically searched PubMed/Medline, Ovid Embase, and Web of Science until November 14th, 2023. We also performed a citation search to detect all relevant studies. Original clinical studies published in the English language were included. RESULTS: Out of 243 articles, sixteen studies have reported various procedural modalities, with or without pharmacological components, in treating NP. Pharmacological procedures, including injections of botulinum toxin, lidocaine, and corticosteroids, led to a level of improvement in case reports and case series. However, botulinum toxin did not show acceptable results in a clinical trial. Moreover, non-pharmacological procedures were as follows: physical therapy, exercise therapy, kinesiotherapy, acupuncture and dry needling, electrical muscle stimulation, surgical decompression, and phototherapy. These treatments result in significant symptom control in refractory cases. Physical therapy can be considered a first-line choice or an alternative in refractory cases. CONCLUSION: Procedural modalities are critical in the multidisciplinary approach to NP, especially for patients who are refractory to topical and oral treatments. Procedural modalities include a spectrum of options that can be applied based on the disease's symptoms and severity.

Biophysics of Frequency-Dependent Variation in Paresthesia and Pain Relief during Spinal Cord Stimulation.

The neurophysiological effects of spinal cord stimulation (SCS) for chronic pain are poorly understood, resulting in inefficient failure-prone programming protocols and inadequate pain relief. Nonetheless, novel stimulation patterns are regularly introduced and adopted clinically. Traditionally, paresthetic sensation is considered necessary for pain relief, although novel paradigms provide analgesia without paresthesia. However, like pain relief, the neurophysiological underpinnings of SCS-induced paresthesia are unknown. Here, we paired biophysical modeling with clinical paresthesia thresholds (of both sexes) to investigate how stimulation frequency affects the neural response to SCS relevant to paresthesia and analgesia. Specifically, we modeled the dorsal column (DC) axonal response, dorsal column nucleus (DCN) synaptic transmission, conduction failure within DC fiber collaterals, and dorsal horn network output. Importantly, we found that high-frequency stimulation reduces DC fiber activation thresholds, which in turn accurately predicts clinical paresthesia perception thresholds. Furthermore, we show that high-frequency SCS produces asynchronous DC fiber spiking and ultimately asynchronous DCN output, offering a plausible biophysical basis for why high-frequency SCS is less comfortable and produces qualitatively different sensation than low-frequency stimulation. Finally, we demonstrate that the model dorsal horn network output is sensitive to SCS-inherent variations in spike timing, which could contribute to heterogeneous pain relief across patients. Importantly, we show that model DC fiber collaterals cannot reliably follow high-frequency stimulation, strongly affecting the network output and typically producing antinociceptive effects at high frequencies. Altogether, these findings clarify how SCS affects the nervous system and provide insight into the biophysics of paresthesia generation and pain relief.

Vitamin B12 deficiency and neuropsychiatric symptoms in Lebanon: A cross-sectional study of vegans, vegetarians, and omnivores.

BACKGROUND: Vitamin B12 deficiency is responsible for a variety of complications, particularly neurological/neuropsychiatric complications, including depression, irritability, paresthesia and insomnia. Since vitamin B12 is found in animal-derived products, vegans/vegetarians are at a greater risk for developing vitamin B12 deficiency. AIMS: This study aims to investigate the occurrence of vitamin B12 deficiency among a sample of adult Lebanese population, with a particular emphasis on assessing the severity of its neurological/neuropsychiatric signs and symptoms, especially among vegans/vegetarians. METHODOLOGY: A cross-sectional study was conducted among a sample of 483 Lebanese adults. Data was collected through a standardized questionnaire that included socio-demographic characteristics, the Patient Health Questionnaire-9 (PHQ-9), Generalized anxiety disorders-7 (GAD-7), and the Insomnia Severity Index (ISI) scales. RESULTS: Among the participants, 11.4% were in the vegan/vegetarian group, and about 43.1% had vitamin B12 deficiency. After analyzing the PHQ-9, GAD-7 and ISI total scores, higher scores were reported in participants with vitamin B12 deficiency, compared to individuals with normal vitamin B12 serum levels (p < 0.001). Regarding the diet type, vegans/vegetarians were more susceptible to developing depression compared to omnivores (mean scores of 11.92 vs 8.02 on the PHQ-9 scale, respectively, with p < 0.001). Of the patients with vitamin B12 deficiency, 81.1% reported having paresthesia compared to 43.7% of individuals with no vitamin B12 deficiency (p < 0.001). CONCLUSION: Vitamin B12 deficiency in Lebanon is notably high and is linked to an increased risk of developing depression, generalized anxiety disorder, insomnia, and paresthesia. Vegans/vegetarians exhibit a higher susceptibility to developing depression compared to omnivores, whereas the risk of developing insomnia, generalized anxiety disorder and paresthesia was statistically insignificant when comparing vegans/vegetarians to omnivores.

Preservation or removal of the lateral nasal wall in endoscopic management of maxillary sinus neoplasia: A comparison of approach related morbidity.

BACKGROUND: The endoscopic modified medial maxillectomy (MMM) and prelacrimal approach (PLA) are two routinely performed endoscopic approaches to the maxillary sinus when access via a middle meatal antrostomy is insufficient. However, there is no data in the literature that has compared outcomes and complication profile between the two procedures to determine which approach is superior. OBJECTIVE: To compare the approach related morbidity of PLA and MMM. METHODS: A retrospective cohort study of all consecutive adult patients undergoing either MMM or PLA from 2009 to 2023 were identified. The primary outcome was development of epistaxis, paraesthesia, lacrimal injury, iatrogenic sinus dysfunction within a minimum of 3 months post-operative follow up. RESULTS: 39 patients (44 sides) underwent PLA and 96 (96 sides) underwent MMM. There were no statistically significant differences between the rates of paraesthesia (9.1 % vs 14.6 %, p = 0.367) or prolonged paraesthesia (2.3 % vs 5.2 %, p = 0.426), iatrogenic maxillary sinus dysfunction (2.3 % vs 5.2 %, p = 0.426) or adhesions requiring removal (4.5 % vs 4.2 %, p = 0.918). No cases of epiphora or nasal cavity stenosis occurred in either arm in our study. CONCLUSIONS: According to our data, the endoscopic modified medial maxillectomy and prelacrimal approach are both equally safe approaches with their own benefits to access.

Biomechanical analysis and comparison between 'Zeta' miniplate design and conventional miniplate system for fixation of fracture segments in transition zone of parasymphysis body region of mandible - an in vitro study.

The parasymphysis area of the mandible is highly dynamic because it is subjected to both occlusal and muscular forces. As a result, the fractures in this transition zone have a special pattern, posing a challenge for surgeons whether to use one miniplate versus two miniplates, as per Champy's recommendations. The commonest complication resulting to treat this area is mental nerve paraesthesia due to the dissection and stretching of the nerve. Hence, an in vitro research study of a newly designed 'Zeta' miniplate is performed, to evaluate the biomechanical behaviour using finite element (FE) analysis and biomechanical analysis along with a comparison study with the conventional miniplate configurations. The results showed that the Zeta miniplate produces the lowest stresses 17.511 MPa and the least total structural deformation of 0.0011 mm after applying the maximum occlusal bite force. On application of torsional load, total structural deformation was 0.0004 mm and von Mises (VM) stress value was 0.24 MPa which was lowest when compared with the two miniplate system. Hence, the newly developed Zeta miniplate is superior in terms of stability. Another benefit of its design is that it helps in preventing mental nerve paraesthesia and tooth root damage while fixing and stabilising the fractured bony segments.

Perioral Paresthesia, Generalize Muscle Cramps, and Rhabdomyolysis After a Socotra Island Blue Baboon Tarantula (Monocentropus Balfouri) Bite.

BACKGROUND: Literature on systemic envenomation caused by tarantula bites, particularly from the Theraphosidae family, is relatively scarce. This case report provides a formal description of the first known instance of systemic envenomation caused by the Socotra Island Blue Baboon Tarantula (Monocentropus balfouri). CASE REPORT: In this case, a 23-year-old employee of an exotic pet shop suffered from perioral paresthesia, generalized muscle cramps, and rhabdomyolysis because of a Monocentropus balfouri bite. His symptoms were successfully relieved with oral benzodiazepines. EMERGENCY PHYSICIAN BE AWARE OF THIS?: This case highlights the potential for serious complications resulting from the bite of Monocentropus balfouri, a species gaining popularity among global exotic pet collectors.

Lazertinib as a frontline treatment in patients with EGFR-mutated advanced non-small cell lung cancer: Long-term follow-up results from LASER201.

OBJECTIVE: This analysis of the first-line cohort of LASER201 study evaluated the efficacy and safety of lazertinib 240 mg as a frontline therapy for epidermal growth factor receptor (EGFR)-mutated locally advanced or metastatic non-small cell lung cancer (NSCLC). METHODS: A total of 43 patients, with EGFR mutation-positive (Exon19Del, n = 24; L858R, n = 18; G719X, n = 1) locally advanced or metastatic NSCLC who had not previously received EGFR tyrosine kinase inhibitor (EGFR TKI) therapy, received once-daily lazertinib 240 mg. EGFR mutation status was confirmed by local or central testing. The primary endpoint was objective response rate (ORR) assessed by blinded independent central review. Secondary efficacy endpoints included duration of response (DoR), disease control rate (DCR), progression-free survival (PFS), tumor shrinkage, and overall survival (OS). RESULTS: At the primary data cut-off (DCO; January 8, 2021), the ORR was 70 % (95 % confidence interval [CI]: 56.0-83.5), DCR was 86 % (95 % CI: 75.7-96.4) and the median DoR was 23.5 (95 % CI: 12.5-not reached) months. The median PFS was 24.6 (95 % CI: 12.2-30.2) months. At the final DCO (March 30, 2023), the median OS was not estimable and the median follow-up duration for OS was 55.2 [95 % CI: 22.8-55.7] months. OS rates at 36 months and 54 months were 66 % (95 % CI: 47.5-79.3 %) and 55 % (95 % CI: 36.6-70.7 %), respectively. The most commonly reported TEAEs were rash (54 %), diarrhea (47 %), pruritus (35 %), and paresthesia (35 %). No drug-related rash or pruritus TEAEs of grade 3 or higher were reported. Diarrhea and paresthesia of grade 3 or higher were reported in 3 (7 %) and 1 (2 %) patients, respectively. CONCLUSION: This analysis demonstrated long-term clinical benefit with lazertinib 240 mg in patients with EGFR-mutated NSCLC who had not previously received EGFR TKIs. The safety profile for lazertinib was tolerable and consistent with that previously reported.

Adjunctive Effect of Photobiomodulation Therapy with Nd:YAG Laser in the Treatment of Inferior Alveolar Nerve Paresthesia.

Background: Disruption of peripheral branches of the trigeminal nerve in the field of maxillofacial surgery is a known risk due to the close connection of these branches with the bony structures of the maxilla and mandible. As a result, injuries of the lingual nerve and inferior alveolar nerve take place within routine maxillofacial surgery procedures, including local anesthetic injection, wisdom tooth surgery, and dental implant placement, resulting in paresthesia and dysesthesia. During the last three decades, low-level lasers (LLL) have been frequently used in various medical fields. Lately, this application has increased in several sectors. Methods and materials: This experiment was designed to explore the effect of low-level laser therapy (LLLT) with Nd:YAG on the paresthesia and dysesthesia of the lower lip. This ethics committee of Tbzmed, Tabriz, Iran, proved the present experiment with ethical code: IR.TBZMED.REC.1401.839. Results: After completing 10 sessions of laser therapy for the case group consisting of 25 patients with lower lip anesthesia, the visual analog scale index results revealed that following six sessions of laser therapy, a significant difference appeared in contrast to the control group. Also, according to the two-point tests, significant difference among the experimental and the control group appeared after ninth session of the laser therapy. Conclusions: Altogether, these data suggested LLLT with Nd:YAG as an effective treatment option for decreasing the anesthesia of the lower lip.

Exploring Symptom Responses to Upper Limb Neural Test Variations of the Radial Nerve in Patients With Lateral Epicondylalgia: An Observational Study.

OBJECTIVE: Clinical practice guidelines recommend the radial nerve mechanosensitivity evaluation in patients with lateral epicondylalgia. Despite different positions and sequences having been described, no research analyzed how each variation triggers symptoms associated with lateral epicondylalgia. The aim of this study was to explore the effects of different positions and sequences in the upper limb neural tension test 2b (ULNT2b) in symptom responses in patients with lateral epicondylalgia. METHODS: In this observational study, 66 patients underwent 4 test conditions: standard ULNT2b, ULNT2b proximal to distal, ULNT2B with resisted supination, and resisted supination isolated. Paresthesia sensations, symptom reproduction, pain intensity (measured using a visual analog scale), and distribution of painful symptoms data were collected. RESULTS: Significant differences in paresthesia sensations were observed between groups, with significant differences between the standard ULNT2B and other ULNT variations or resisted supination maneuvers. Symptom reproduction also differed significantly across groups, with significant differences between the standard ULNT2B and other ULNT or resisted supination tests. The positive/negative test and percentage of distribution of painful symptoms scores varied significantly across 4 conditions in both lateral and frontal views. Although pain intensity scores during tests were comparable among the tests, distribution of painful symptoms differed significantly. CONCLUSION: Variations in the ULNT2b test can affect symptom responses in patients with lateral epicondylalgia. The standard ULNT2b test appears more effective at reproducing symptoms, intensity of paresthesia, and distribution of painful symptoms compared to other ULNT variations and the resisted supination test. IMPACT: ULNT2b sequences have been shown to elicit varying responses concerning paresthesia, replication of familiar symptoms, positive/negative test results, and distribution of painful symptoms. Clinicians should consider specific test variations during the patients' radial nerve mechanosensitivity assessment to identify aggravating factors reproducing recognizable symptoms. A control group of asymptomatic participants and the role of presence of other comorbidities, psychological factors, or the duration of symptoms were not considered in this study and might play an important role influencing the results of the tests.

Oral dysaesthesia: a special focus on aetiopathogenesis, clinical diagnostics and treatment modalities.

Oral dysaesthesia is a condition characterised by persistent alteration to oral sensation, perceived by the patient to be abnormal and/or unpleasant, in the absence of any mucosal pathology. The condition can be difficult to detect and diagnose. A possible peripheral or central neuropathic aetiology has been proposed. Burning mouth syndrome (BMS) is the most common idiopathic oral dysesthesia in which long-term suffering is often reported by patients. Recent efforts from professional organisations and study groups have provided a consensus on BMS disease definition and diagnostic criteria. Large-scale epidemiological studies are required to provide an accurate estimate for prevalence and incidence of the condition. Meticulous diagnostic investigations which may require interdisciplinary teamwork are often warranted to reach an accurate diagnosis. A combination of interventional modalities, with a holistic approach, is key for successful management and improvement in patients' quality of life.

Round ligament management during minimally invasive groin hernia repair in women: a systematic review and meta-analysis.

BACKGROUND: Female sex has been associated with worse outcomes after groin hernia repair (GHR), including a higher rate of chronic pain and recurrence. Most of the studies in GHR are performed in males, and the recommendations for females extrapolate from these studies, even though females have anatomy intricacies. The round ligament of the uterus (RLU) is associated with pelvic stabilization and plays a role in sensory function. Transection of the RLU during GHR is controversial as it can allow easier mesh placement but can favor genitourinary complications and chronic pain. As no previous meta-analysis compared preserving versus transecting the RLU during minimally invasive (MIS) GHR, we aim to perform a systematic review and meta-analysis evaluating surgical outcomes comparing the approaches. METHODS: Cochrane Central, Embase, and PubMed databases were systematically searched for studies comparing transection versus preservation of the RLU in MIS groin hernia surgeries. Outcomes assessed were operative time, bleeding, surgical site events, hospital stay, chronic pain, paresthesia, recurrence rates, and genital prolapse rates. Statistical analysis was performed using RevMan 5.4.1. Heterogeneity was assessed with I2 statistics. A review protocol for this meta-analysis was registered at PROSPERO (CRD 42023467146). RESULTS: 1738 studies were screened. A total of six studies, comprising 1131 women, were included, of whom 652 (57.6%) had preservation of the RLU during MIS groin hernia repair. We found no statistical difference regarding chronic pain, paresthesia, recurrence rates, and postoperative complications. We found a longer operative time for the preservation group (MD 6.84 min; 95% CI 3.0-10.68; P = 0.0005; I2 = 74%). CONCLUSION: Transecting the RLU reduces the operative time during MIS GHR with no difference regarding postoperative complication rates. Although transection appears safe, further prospective randomized studies with long-term follow-up and patient-reported outcomes are necessary to define the optimal management of RLU during MIS GHR.

Clinical and ultrasound characteristics of deep endometriosis affecting sacral plexus.

OBJECTIVE: To describe the sonomorphological changes and appearance of deep endometriosis (DE) affecting the nervous tissue of the sacral plexus (SP). METHODS: This was a retrospective study of symptomatic patients who underwent radical resection of histologically confirmed DE affecting the SP and who had undergone preoperative transvaginal sonography (TVS) between 2019 and 2023. Lesions were described based on the terms and definitions of the International Deep Endometriosis Analysis (IDEA), International Ovarian Tumor Analysis (IOTA) and Morphological Uterus Sonographic Assessment (MUSA) groups. A diagnosis of DE affecting the SP on TVS was made when the sonographic criteria of DE were visualized in conjunction with fibers of the SP and the presence of related symptoms corresponding to sacral radiculopathy. Clinical symptoms, ultrasound features and histological confirmation were analyzed for each patient included. RESULTS: Twenty-seven patients with DE infiltrating the SP were identified in two contributing tertiary referral centers. Median age was 37 (range, 29-45) years and all patients were symptomatic and presented one or more of the following neurological symptoms: dysesthesia in the ipsilateral lower extremity (n = 17); paresthesia in the ipsilateral lower extremity (n = 10); chronic pelvic pain radiating in the ipsilateral lower extremity (n = 9); chronic pain radiating in the pudendal region (n = 8); and motor weakness in the ipsilateral lower extremities (n = 3). All DE lesions affecting the SP were purely solid tumors in the posterior parametrium in direct contact with, or infiltrating, the S1, S2, S3 and/or S4 roots of the SP. The median of the largest diameter recorded for each of the DE nodules was 35 (range, 18-50) mm. Echogenicity was non-uniform in 23 (85%) of the DE nodules, with all but one of these nodules containing hyperechogenic areas. The shape of the lesions was irregular in 24 (89%) cases. Only one lesion exhibited a lobulated form, with all other irregular lesions showing a spiculated appearance. An acoustic shadow was produced in 20 (74%) of the nodules, all of which were internal. On color or power Doppler examination, 21 (78%) of the nodules showed no signal (color score of 1). The remaining six (22%) lesions showed a minimal color content (color score of 2). According to pattern recognition, most DE nodules were purely solid, non-uniform, hypoechogenic nodules containing hyperechogenic areas, with internal shadows and irregular spiculated contours, and were poorly vascularized on color/power Doppler examination. CONCLUSION: The ultrasound finding of a parametrial, unilateral, solid, non-uniform, hypoechogenic nodule with hyperechogenic areas and possible internal shadowing, as well as irregular spiculated contours, demonstrating poor vascularization on Doppler examination in proximity to or involving the structures of the SP, indicates DE affecting the SP. © 2024 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.