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Anesthesiology Jun 2023The authors hypothesized that both perineural and systemic dexamethasone as adjuncts to bupivacaine increase the duration of an ulnar nerve block compared with... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
The authors hypothesized that both perineural and systemic dexamethasone as adjuncts to bupivacaine increase the duration of an ulnar nerve block compared with bupivacaine alone, and that systemic dexamethasone is noninferior to perineural dexamethasone.
METHODS
The authors performed bilateral ulnar nerve blocks with 3 ml bupivacaine 5 mg/ml in 16 healthy volunteers on two trial days. According to randomization, subjects received adjunct treatment with 1 ml dexamethasone 4 mg/ml + 1 ml of saline (perineural condition) in one arm and 2 ml saline in the other arm (systemic condition, through absorption and redistribution of the contralaterally administered perineural dexamethasone) on one trial day; and 2 ml saline in one arm (placebo condition) and 2 ml of lidocaine in the other arm (lidocaine condition) on the other trial day. The primary outcome was the duration of the sensory nerve block assessed by temperature discrimination.
RESULTS
Mean sensory block duration was 706 ± 94 min for the perineural condition, 677 ± 112 min for the systemic condition, and 640 ± 121 min for the placebo condition. The duration of the sensory nerve block was greater with perineural dexamethasone versus placebo (mean difference 66 min (95% CI, 23 to 108). Block duration was similar between systemic dexamethasone and placebo (mean difference 36 min; 95% CI, -30 to 103).
CONCLUSIONS
Perineural dexamethasone as an adjunct to bupivacaine in healthy volunteers resulted in a greater duration of an ulnar nerve block when compared with placebo. Systemic dexamethasone resulted in a similar duration as placebo.
Topics: Humans; Dexamethasone; Anesthetics, Local; Healthy Volunteers; Bupivacaine; Nerve Block; Lidocaine; Pain, Postoperative; Double-Blind Method
PubMed: 36912613
DOI: 10.1097/ALN.0000000000004557 -
Current Opinion in Anaesthesiology Oct 2023Moderate-to-severe pain is common and remains a significant problem. Compared with opioid analgesia alone, single-shot peripheral nerve blockade has been associated with... (Review)
Review
PURPOSE OF REVIEW
Moderate-to-severe pain is common and remains a significant problem. Compared with opioid analgesia alone, single-shot peripheral nerve blockade has been associated with improved pain relief and the potential of decreased side effects. Single-shot nerve blockade, however, is limited by its relatively short duration of action. In this review, we aim to summarize the evidence related to local anaesthetic adjuncts for peripheral nerve blockade.
RECENT FINDINGS
Dexamethasone and dexmedetomidine exhibit characteristics that most closely resemble the ideal local anaesthetic adjunct. In upper limb block, dexamethasone has been demonstrated to be superior to dexmedetomidine regardless of administration route for the duration of sensory and motor blockade as well as the duration of analgesia. No clinically significant differences between intravenous and perineural dexamethasone were found. Perineural and intravenous dexamethasone have the potential to prolong sensory blockade to a greater extent than motor blockade. The evidence indicates that the mechanism of action of perineural dexamethasone in upper limb block is systemic in nature. Unlike perineural dexmedetomidine, intravenous dexmedetomidine has not been shown to result in differences in the characteristics of regional blockade compared with local anaesthetic alone.
SUMMARY
Intravenous dexamethasone is the local anaesthetic adjunct of choice, increasing the duration of sensory and motor blockade as well as the duration of analgesia by 477, 289 and 478 min, respectively. In view of this, we recommend consideration of the intravenous administration of dexamethasone at a dose of 0.1-0.2 mg/kg for all patients undergoing surgery whatever the level of postoperative pain, mild, moderate or severe. Further research should focus on the potential synergism of action between intravenous dexamethasone and perineural dexmedetomidine.
Topics: Humans; Anesthetics, Local; Dexamethasone; Dexmedetomidine; Pain, Postoperative; Peripheral Nerves
PubMed: 37314172
DOI: 10.1097/ACO.0000000000001272 -
Eye (London, England) Apr 2023Perineural invasion (PNI) in cutaneous squamous cell carcinoma (SCC) of the periocular region is a prognostic marker of adverse tumour outcomes. PNI carries a... (Review)
Review
Perineural invasion (PNI) in cutaneous squamous cell carcinoma (SCC) of the periocular region is a prognostic marker of adverse tumour outcomes. PNI carries a well-established risk of tumour recurrence, regional metastasis and higher likelihood of mortality. This review will explore and stratify the risks conferred by histological PNI parameters. The radiological features of perineural spread (PNS) and the imaging sequences that delineate these findings will also be highlighted. Surgical excision with en face margin control is the preferred technique for achieving histological clearance. Adjuvant radiotherapy improves treatment outcomes in the setting of concomitant high-risk features. For locally advanced or metastatic cutaneous SCC, immunotherapy represents a novel treatment alternative. This review will provide an algorithm for the diagnosis and management of periocular SCC with PNI and PNS.
Topics: Humans; Carcinoma, Squamous Cell; Skin Neoplasms; Neoplasm Recurrence, Local; Treatment Outcome; Radiotherapy, Adjuvant; Neoplasm Invasiveness; Prognosis; Retrospective Studies
PubMed: 36400852
DOI: 10.1038/s41433-022-02306-w -
The British Journal of Radiology Aug 2022Acetabular paralabral cysts are common and are almost always associated with labral tears. Uncommonly, they extend into the periacetabular soft tissues or may propagate...
OBJECTIVE
Acetabular paralabral cysts are common and are almost always associated with labral tears. Uncommonly, they extend into the periacetabular soft tissues or may propagate along peripheral nerves causing pain and hip dysfunction. The aim was to evaluate the clinical and MRI presentations of such cases including perineural propagation.
METHODS
Retrospective cross-sectional study with a search of electronic health records for cases of acetabular paralabral cysts demonstrating perineural propagation was performed. Clinical and MR imaging features were tabulated after re-review by experienced musculoskeletal radiologists, and available outcomes were recorded. Descriptive statistics were performed.
RESULTS
14 cases were recorded. The mean age was 56.9 years (range = 30-79 years) and female:male ratio was 1:2.6. The commonest presenting complaint was hip pain (10/14, 71.4%). Other complaints included groin pain, perineal pain and hip dysfunction. No symptoms were attributed to the acetabular paralabral cyst in 3/14 patients (21.4%). None had foot drop. The cysts were multilocular in all cases and were homogenously T2 hyperintense in 13/14 (92.9%). Labral tears were identified in 11/14 cases (78.6%). The sciatic nerve was most commonly involved in 5/14 cases (35.7%) with the obturator, medial femoral cutaneous nerve, femoral nerve, superior and inferior gluteal nerves also affected.No intervention was undertaken in 9/14 cases (64.3%). 5/14 (35.7%) underwent image guided aspiration and corticosteroid injection. 4/5 such patients reported reduced pain following the procedure.
CONCLUSION
Paralabral cysts demonstrating perineural propagation are uncommon and exhibit varied presentations. Most patients who underwent image-guided or surgical interventions reported an improvement in symptoms.
ADVANCES IN KNOWLEDGE.
This is the first description of a series of patients with acetabular paralabral cysts demonstrating perineural propagation in the literature. A comprehensive description of their clinical and imaging characteristics and interventions/outcomes where relevant is provided.
Topics: Acetabulum; Adult; Aged; Arthralgia; Arthroscopy; Cross-Sectional Studies; Cysts; Female; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Retrospective Studies
PubMed: 35762342
DOI: 10.1259/bjr.20211306 -
American Journal of Clinical Dermatology Sep 2021Perineural invasion is an infiltrative process of peripheral nerves by the primary neoplasm within the immediate vicinity. Aggressive forms of keratinocyte carcinomas,... (Review)
Review
Perineural invasion is an infiltrative process of peripheral nerves by the primary neoplasm within the immediate vicinity. Aggressive forms of keratinocyte carcinomas, such as basal cell and squamous cell carcinomas, may feature perineural invasion, which is often associated with tumor recurrence and poorer prognosis. Diagnosis requires a high clinical suspicion. Imaging and histopathology are used to assess for extent of disease while surgical excision with complete circumferential peripheral and margin assessment is the treatment goal. However, there is still significant uncertainty about adjuvant chemotherapy and definitive management guidelines. Here, we summarize the current understanding of this complex pathogenic process, the clinical presentation, and the significance of perineural inflammation. We also discuss the recommendations about staging, prognosis, adjuvant radiotherapy, and general guidelines for managing keratinocyte carcinomas with perineural invasion. A better understanding of perineural invasion is essential to improve diagnosis, tailor interventions, and mitigate patient morbidity and mortality.
Topics: Carcinoma, Squamous Cell; Humans; Keratinocytes; Neoplasm Invasiveness; Neoplasm Recurrence, Local; Peripheral Nervous System Neoplasms
PubMed: 34105084
DOI: 10.1007/s40257-021-00615-6 -
Frontiers in Genetics 2022Carcinomas of the oral cavity and oropharynx belong among the ten most common malignancies in the human population. The prognosis of head and neck squamous cell... (Review)
Review
Carcinomas of the oral cavity and oropharynx belong among the ten most common malignancies in the human population. The prognosis of head and neck squamous cell carcinoma (HNSCC) is determined by the degree of invasiveness of the primary tumor and by the extent of metastatic spread into regional and distant lymph nodes. Moreover, the level of the perineural invasion itself associates with tumor localization, invasion's extent, and the presence of nodal metastases. Here, we summarize the current knowledge about different aspects of epigenetic changes, which can be associated with HNSCC while focusing on perineural invasion (PNI). We review epigenetic modifications of the genes involved in the PNI process in HNSCC from the omics perspective and specific epigenetic modifications in OSCC or other neurotropic cancers associated with perineural invasion. Moreover, we summarize DNA methylation status of tumor-suppressor genes, methylation and demethylation enzymes and histone post-translational modifications associated with PNI. The influence of other epigenetic factors on the HNSCC incidence and perineural invasion such as tobacco, alcohol and oral microbiome is overviewed and HPV infection is discussed as an epigenetic factor associated with OSCC and related perineural invasion. Understanding epigenetic regulations of axon growth that lead to tumorous spread or uncovering the molecular control of axon interaction with cancer tissue can help to discover new therapeutic targets for these tumors.
PubMed: 35571032
DOI: 10.3389/fgene.2022.848557 -
Cell & Bioscience Jun 2021The perineural invasion (PNI), which refers to tumor cells encroaching on nerve, is a clinical feature frequently occurred in various malignant tumors, and responsible... (Review)
Review
The perineural invasion (PNI), which refers to tumor cells encroaching on nerve, is a clinical feature frequently occurred in various malignant tumors, and responsible for postoperative recurrence, metastasis and decreased survival. The pathogenesis of PNI switches from 'low-resistance channel' hypothesis to 'mutual attraction' theory between peripheral nerves and tumor cells in perineural niche. Among various molecules in perineural niche, microRNA (miRNA) as an emerging modulator of PNI through generating RNA-induced silencing complex (RISC) to orchestrate oncogene and anti-oncogene has aroused a wide attention. This article systematically reviewed the role of microRNA in PNI, promising to identify new biomarkers and offer cancer therapeutic targets.
PubMed: 34187567
DOI: 10.1186/s13578-021-00630-4 -
FASEB BioAdvances Oct 2021The density of nerves in cancer is emerging as a relevant clinical parameter for patient survival. Nerves in the tumor microenvironment have been associated with poor... (Review)
Review
The density of nerves in cancer is emerging as a relevant clinical parameter for patient survival. Nerves in the tumor microenvironment have been associated with poor survival and recurrence, particularly if involved in perineural invasion. However, usually only a few nerves inside a tumor are affected by perineural invasion, while most nerves are not. Mechanistic studies have shown nerve-secreted factors promote tumor growth and invasion thereby making tumors more aggressive. Therefore, the overall number of nerves in the tumor microenvironment should be more representative of the nerve-tumor biological interaction than perineural invasion. This review summarizes the available clinical information about nerve density as a measure of clinical outcome in cancer and explores the mechanisms underlying nerve density in cancer, specifically, neurogenesis, axonogenesis, and neurotropism.
PubMed: 34632313
DOI: 10.1096/fba.2021-00046 -
The Laryngoscope Jun 2022To describe outcomes of advanced head and neck cutaneous squamous cell carcinoma (cSCC) with clinical perineural invasion (cPNI) treated with immune checkpoint inhibitor...
OBJECTIVES/HYPOTHESIS
To describe outcomes of advanced head and neck cutaneous squamous cell carcinoma (cSCC) with clinical perineural invasion (cPNI) treated with immune checkpoint inhibitor (ICI) therapy, and to describe post-treatment radiographic findings in the context of clinical response to treatment using a new grading system.
STUDY DESIGN
Retrospective chart review.
METHODS
Retrospective chart review was performed for 11 patients treated with ICI for head and neck cSCC with cPNI of large named nerves. The primary outcome was response to treatment as defined by radiographic and clinical evidence. Clinical responses were defined as improvement in symptoms of neuropathic pain, hypoesthesia, nerve weakness, or decrease in visible tumor. Imaging studies were graded based on a new classification system for perineural invasion and reviewed by two neuroradiologists since RECISTv1.1 is inadequate to adjudicate response in these patients.
RESULTS
Nine (82%) patients had radiographic perineural disease control on ICI. Eight patients had improved radiographic perineural disease and one had stable disease. Of these, complete resolution of radiographic evidence of perineural disease was seen in only one patient. Seven (64%) patients had clinical responses, with either improved or stable radiographic disease.
CONCLUSIONS
ICI therapy is a viable treatment option for head and neck cSCC with cPNI. Radiographic and clinical evidence of response correlate well, with improvement in neuropathic pain being the most sensitive clinical marker of response. Even with favorable findings on repeat imaging and stable clinical course, complete resolution of perineural thickening and enhancement is rare. A grading system for classifying changes in perineural disease over time is proposed.
LEVEL OF EVIDENCE
4 Laryngoscope, 132:1213-1218, 2022.
Topics: Carcinoma, Squamous Cell; Head and Neck Neoplasms; Humans; Immunotherapy; Neoplasm Invasiveness; Neuralgia; Retrospective Studies; Skin Neoplasms; Squamous Cell Carcinoma of Head and Neck
PubMed: 34797598
DOI: 10.1002/lary.29953 -
Pathology, Research and Practice Mar 2024Perineuriomatous melanocytic nevi are rare and this may indicate the similar embryological source of melanocytes and peripheral nerves in the neural crest. Neurotized...
BACKGROUND
Perineuriomatous melanocytic nevi are rare and this may indicate the similar embryological source of melanocytes and peripheral nerves in the neural crest. Neurotized melanocytic nevi may resemble nerve sheath tumors histologically, and show schwannian differentiation. However, literature on whether neurotized nevi differentiate into perineural cells is controversial. We examined our cases of neurotized nevi for evidence of perineural differentiation.
MATERIALS AND METHODS
A total of 100 benign nevi with large neurotized component (microscopically involved a low power field 4.2 mm in diameter) were prospectively evaluated in excisional biopsy samples. Immunohistochemical stainings for EMA, Claudin1, Glut1 and neurofilament were performed.
RESULTS
Perineural differentiation was immunohistochemically detected in the neurotized component of the nevi in 61% of the cases with EMA and in all the cases with Glut1 and Claudin1. Axonal differentiation was not detected with neurofilament. The expression pattern, especially with Glut1, was usually in form of partial or complete staining surrounding the Meissner's corpuscle-like structure (MCLS). Also, a linear/curvilinear staining pattern was observed particularly with Claudin1. A diffuse staining pattern with EMA, Glut1 and Claudin1 was detected in a case with a microscopically distinct whorl structure, and in which spindle cells are separated from the superficial epithelioid melanocytes with an abrupt transition histologically. These findings of the case are compatible with previous reports of perineuromatous nevus.
CONCLUSION
Perineural differentiation is not uncommon and immunohistochemically observed in all nevi with a relatively large component of neurotization. To prevent misdiagnosing desmoplastic melanoma and overtreating patients, it is crucial to be aware of perineuromatous nevi.
Topics: Humans; Skin Neoplasms; Glucose Transporter Type 1; Immunohistochemistry; Nevus; Nevus, Pigmented; Melanocytes
PubMed: 38324967
DOI: 10.1016/j.prp.2024.155184