Teflon Granuloma Research Articles

Revisiting the Efficacy of Redo Microvascular Decompression for Trigeminal Neuralgia

BACKGROUNDMicrovascular decompression (MVD) is an effective non-destructive neurosurgical procedure for trigeminal neuralgia (TN). However, some patients may undergo surgery failure or experience pain recurrence, sparking debates on the need for reoperation. METHODSWe conducted a retrospective analysis of 103 cases of patients with primary TN who underwent re-do MVD at our center between January 2020 and December 2022. Comparative prognostic assessments were performed by comparing these cases against a cohort of 348 patients who underwent primary MVD during the same study period. RESULTSDuring the redo MVD cases, adhesions of arachnoid membranes (80.6%) and Teflon granuloma (86.4%) as well as remaining vascular compression (36.9%) were observed. After the reoperation, an immediate relief rate of 94.2% was observed. During a mean follow-up period of 17.4±4.4 months, a long-term relief rate of 89.3% was achieved. Postoperative complications included 3 cases of persistent paraesthesia, one case each of hearing loss, cerebrospinal fluid leak and facial palsy. Ten cases without evident compression received nerve combing (NC) and all experienced immediate complete relief, with only one patient experiencing recurrence 9 months after surgery. Compared to the primary MVD group, the reoperation group had a higher average age, longer disease duration and operating time (P<0.05). However, there were no significant differences in immediate relief rate, long-term relief rate, or complications between the two groups. The main cause of persistent symptom was inadequate decompression, such as missing the offending vessel; while the recurrent was primarily due to Teflon adhesion or granuloma formation. CONCLUSIONThe redo MVD for TN is equally efficacious and safe compared to the primary procedure, with an emphasis on meticulous dissection and thorough decompression. Additionally, NC proves to be an effective supplementary option for patients without obvious compression.

Repeat Microvascular Decompression for Recurrent Trigeminal Neuralgia.

To review our experience with patients presenting with recurrent trigeminal neuralgia (TN) and who have undergone repeat microvascular decompression surgery (rMVD). This retrospective observational study was conducted at the Department of Neurosurgery at a university hospital. Patients who initially experienced complete pain relief after the first MVD but later had a recurrence of TN symptoms which required an rMVD were included in the study. Pain control outcomes were evaluated based on the Barrow Neurological Institute (BNI) scale score. Of the 375 patients who underwent MVD for TN over a 20-year period, 19 patients (6 females and 13 males) with a mean age of 57.68 ± 9.78 years developed symptom recurrence which necessitated an rMVD (5.06%). The average duration of the symptoms before the rMVD was 16.1 ± 19.36 months. The mean BNI score of the patients before the rMVD was 4.5 ± 0.5. Recurrence was primarily attributed to compression by a new offending vessel (n=9, 47.4%) or a Teflon granuloma (n=8, 42.1%). Two patients (10.5%) did not have any identifiable compression. During a follow-up period of 106.3 ± 58.3 months, excellent pain relief (BNI-I) was achieved in 10 patients (52.6%). Eight patients (42.1%) experienced a good outcome (BNI-III), and one patient (5.3%) experienced a poor outcome (BNI-IV). Recurrence of TN symptoms can occur even after an initially successful MVD. Subsequent MVDs should be considered as the primary treatment option for recurrent TN, as it significantly controls pain with low morbidity.

Microsurgical posterior fossa re-exploration for recurrent trigeminal neuralgia after previous microvascular decompression: common grounds—scarring, deformation, and the “piston effect”

ObjectiveMicrovascular decompression (MVD) is a well-accepted treatment modality for trigeminal neuralgia (TN) with high initial success rates. The causes for recurrence of TN after previously successful MVD have not been fully clarified, and its treatment is still a matter of debate. Here, we present the surgical findings and the clinical outcome of patients with recurrent TN after MVD who underwent posterior fossa re-exploration.MethodsMicrosurgical posterior fossa re-exploration was performed in 26 patients with recurrent TN (mean age 59.1 years) who underwent MVD over a period of 10 years. The trigeminal nerve was exposed, and possible factors for recurrent TN were identified. Arachnoid scars and Teflon granulomas were dissected meticulously without manipulating the trigeminal nerve. Outcome of posterior fossa re-exploration was graded according to the Barrow Neurological Institute (BNI) pain intensity score. Follow-up was analyzed postoperatively at 3, 12, and 24 months and at the latest available time point for long-term outcome.ResultsThe mean duration of recurrent TN after the first MVD was 20 months. Pain relief was achieved in all patients with recurrent TN on the first postoperative day. Intraoperative findings were as follows: arachnoid scar tissue in 22/26 (84.6%) patients, arterial compression in 1/26 (3.8%), venous contact in 8/26 (30.8%), Teflon granuloma in 14/26 (53.8%), compression by an electrode in Meckel’s cave used for treatment of neuropathic pain in 1/26 (3.8%), evidence of pulsations transmitted to the trigeminal nerve through the Teflon inserted previously/scar tissue (“piston effect”) in 15/26 (57.7%), and combination of findings in 18/26 (69.2%). At long-term follow-up (mean 79.5 months; range, 29–184 months), 21/26 (80.8%) patients had favorable outcome (BNI I-IIIa). New hypaesthesia secondary to microsurgical posterior fossa re-exploration occurred in 5/26 (19.2%) patients.ConclusionsPosterior fossa re-exploration avoiding manipulation to the trigeminal nerve, such as pinching or combing, may be a useful treatment option for recurrent TN after previously successful MVD providing pain relief in the majority of patients with a low rate of new hypaesthesia.

Teflon Granuloma: A Common Cause of Recurrent Trigeminal Neuralgia

Trigeminal neuralgia (TN) is a common pain syndrome of the nervous system,. Although about 90% patients who were refractory to medications could be free from pain after microvascular decompression (MVD), some patients did experience recurrence. The study aimed to analyze clinical characteristics of patients with recurrent TN, recurrence factors of TN, and prognosis after re-do MVD. Clinical data and at least 12 months follow-up of patients with recurrent TN who underwent re-do MVD in our hospital from 2005 to 2020 were collected and analyzed. A total of 14 patients with recurrent TN were enrolled eventually; adhesive arachnoid membranes were found in all patients. Teflon granuloma was found in 10 patients, new neurovascular compression (NVC) in 3 patients, and vascular displacement in 1 patient. Pain disappeared in 12 patients and relieved in 2 patients, but 4 patients experienced mild facial numbness and 1 patient suffered from incision infection after re-do MVC. No serious surgery-related complications and pain recurrences were recorded. Teflon granuloma was the most common cause of TN recurrence in current study, new NVC was also saw in some patients. Patients with recurrent TN could get satisfactory results from re-do MVD.

Long-Term Retrospective Analysis of Re-do Microvascular Decompression in Patients With Hemifacial Spasm.

Objective: To explore the clinical characteristics of patients with persistent or recurrent hemifacial spasm (HFS) and the experience of microvascular decompression (MVD) in the treatment of such patients to accumulate additional clinical evidence for optimal treatment protocols.Methods: We retrospectively analyzed the clinical data, surgical methods and treatment efficacies of 176 patients with persistent or recurrent HFS from January 2009 to January 2018.Results: Missing compression zones was the main reason for symptom persistence (87.50%) or recurrence (71.50%) after MVD treatment of HFS. We divided the surgical area into three zones. Most persistent or recurrent cases had decompression only in the root exit zone (REZ) (Zone 1) but missed the ventrolateral pons-involved area (Zone 2) or the bulbopontine sulcus-involved area (Zone 3) in the first MVD. Too much use of Teflon (12.50%), arachnoid adhesions (5.60%) and Teflon granulomas (10.40%) can also cause a recurrence. The difference between preoperative and postoperative Cohen scores was statistically significant in persistent or recurrent HFS patients (p<0.05). The postoperative follow-up time ranged from 36 to 108 months (71.75 ± 22.77).Conclusions: MVD should be performed in the compression site, which is mostly located at the brainstem/facial REZ. Intraoperative exploration should be conducted in accordance with the abovementioned zones to effectively avoid missing offending vessels. Re-do MVD is effective in patients with persistent or recurrent HFS.

Mechanism underlying cranial nerve rhizopathy

The cranial nerve rhizophathy, commonly presented with trigeminal neuralgia (TN) or hemifacial spasm (HFS), is a sort of hyperexcitability disorders with higher incidence in senior Asian. In this paper, a novel hypothesis on the pathogenesis is proposed and with which some clinical phenomena are explained.In those with crowded cerebellopontine angle in anatomy, the cranial nerve root and surrounding vessel are getting closer and closer to each other with aging and finally the neurovascular conflict happens. As the interfacial friction associated with pulse, the nerve incurs demyelination. Since this pathological change develops to a certain degree, some transmembrane proteins emerge from the nerve due to a series of signaling pathway mediated by inflammatory cytokines. Among them, voltage-gated (Nav1.3) and mechanosensitive (Piezo2) ion channels may play the important role. With pulsatile compressions, the Piezo2 drives the resting potential toward depolarization forming a state of subthreshold membrane potential oscillation. Under this condition, just an appropriate pressure can make the membrane potential easy to reach threshold and activate the sodium channel, eventually generating conductible action potentials from the axon. When these ectopic action potentials propagate to the central nerve system, an illusion of sharp pain is perceived; while to the nerve-muscle junctions, an attack of irregular muscle constriction occurs.This hypothesis can well explain the symptomatic manifestation of paroxysmal attacks aroused by emotions. When we get nervous or excited, our heart rate and blood pressure alter correspondingly, which may give rise to “a just right pressure” – with specific frequency, amplitude and angle – impacting the suffered nerve to reach the threshold of impulse ignition. After a successful microvascular decompression surgery, the trigger is gone (there is no compression anymore) and the symptom is alleviated. While the postoperative recurrence could be attributable to Teflon granuloma development if had been placed improperly – for this nerve root has been susceptible no matter to arteries or to neoplasms. Besides, it may illustrate the clinical phenomenon that secondary TN or HFS cases are seldom caused by schwannoma: with a proliferative sheath, the nerve root is actually insulated. By contrast, not all neurovascular contacts can lead to the onset: it demands an exclusive extent of demyelination firstly.

Polytetrafluoroethylene granuloma-associated facial palsy following microvascular decompression.

Microvascular decompression (MVD) may be employed in the management of hemifacial spasm (HFS), wherein a pledget of polytetrafluoroethylene (i.e., Teflon, Chemours, Wilmington DE) is sometimes introduced to separate an offending vessel from the cisternal segment of facial nerve. Rarely, Teflon may cause a granulomatous reaction resulting in nerve palsy. We here present the first case series of facial palsy thought to be secondary to Teflon granuloma following MVD for HFS. A data repository of 1,312 patients with facial palsy was reviewed to identify individuals who had previously undergone MVD for HFS. Data collected include age at time of MVD, age at onset of facial weakness and at presentation, House-Brackmann scores, clinician-graded facial function using the Electronic Facial Paralysis Assessment scale, imaging findings, and therapeutic interventions and outcomes. Six patients meeting criteria were identified. Average time between MVD with Teflon placement and onset of facial weakness was 16.1 (±4.9) years (range 9.3-23.3 years). Initial House-Brackmann scores were as follows: four patients with V/VI and one each with III/VI and IV/VI. Interventions included eyelid weight placement (n = 3), chemodenervation (n = 2), static suspension with tensor fascia latae (n = 2), dynamic reanimation with cranial nerves V to VII transfer (n = 1), and temporalis muscle transfer (n = 1). Teflon granuloma should be considered in the differential diagnosis for patients presenting with new onset facial weakness with a previous history of MVD for HFS. It remains unknown whether early granuloma extirpation is effective. Prompt diagnosis allows consideration of time-sensitive nerve transfer procedures to reanimate facial function. 4 Laryngoscope, 130:1422-1427, 2020.

Intracranial foreign material granulomas after cranial surgery.

Various synthetic materials are used in neurosurgery and left in place intentionally during surgery for several purposes such as hemostasis, dural closure, or cranioplasty. Although leaving such substances in surgical sites is considered safe, in general, foreign body granuloma may occur months or years after intracranial surgery. Thus, far relatively little is known about treatment and outcome of such lesions. A systematic review of 3466 histopathological examinations after cranial surgeries achieved over a 13-year period was performed. After excluding patients with Teflon granulomas or infection, a total of 12 patients with foreign body granulomas induced by synthetic material used in a prior surgery were identified. Patient records, imaging studies, and histopathological data were analyzed. Furthermore, postoperative outcome was assessed. Mean age at the second surgery was 51years (range, 11-68years). The median time between the primary and the secondary surgery was 13months (range, 1-545months). Eight patients (75%) presented with signs and symptoms related to the foreign body granulomas. Total resection of the foreign body granulomas was performed in all patients. The granulomas were induced by oxidized cellulose polymer (n = 6), suture material (n = 3), Gelfoam (n = 1), methylmethacrylate (n = 1), and bone wax (n = 1). The mean postoperative follow-up time was 54months (range 1-137months). There was symptomatic improvement in all instances. Imaging studies did not demonstrate any recurrence. Despite its rarity, foreign body granuloma should be taken into consideration in the differential diagnosis of intracranial mass lesions especially in cases of suspected tumor recurrence after prior surgery. The pathogenesis of foreign body granuloma still needs further clarification. Our study demonstrates that they have good prognosis after surgical removal.

Navigation-Linked Heads-Up Display in Intracranial Surgery: Early Experience.

BACKGROUNDThe use of intraoperative navigation during microscope cases can be limited when attention needs to be divided between the operative field and the navigation screens. Heads-up display (HUD), also referred to as augmented reality, permits visualization of navigation information during surgery workflow.OBJECTIVETo detail our initial experience with HUD.METHODSWe retrospectively reviewed patients who underwent HUD-assisted surgery from April 2016 through April 2017. All lesions were assessed for accuracy and those from the latter half of the study were assessed for utility.RESULTSSeventy-nine patients with 84 pathologies were included. Pathologies included aneurysms (14), arteriovenous malformations (6), cavernous malformations (5), intracranial stenosis (3), meningiomas (27), metastasis (4), craniopharygniomas (4), gliomas (4), schwannomas (3), epidermoid/dermoids (3), pituitary adenomas (2) hemangioblastoma (2), choroid plexus papilloma (1), lymphoma (1), osteoblastoma (1), clival chordoma (1), cerebrospinal fluid leak (1), abscess (1), and a cerebellopontine angle Teflon granuloma (1). Fifty-nine lesions were deep and 25 were superficial. Structures identified included the lesion (81), vessels (48), and nerves/brain tissue (31). Accuracy was deemed excellent (71.4%), good (20.2%), or poor (8.3%). Deep lesions were less likely to have excellent accuracy (P = .029). HUD was used during bed/head positioning (50.0%), skin incision (17.3%), craniotomy (23.1%), dural opening (26.9%), corticectomy (13.5%), arachnoid opening (36.5%), and intracranial drilling (13.5%). HUD was deactivated at some point during the surgery in 59.6% of cases. There were no complications related to HUD use.CONCLUSIONHUD can be safely used for a wide variety of vascular and oncologic intracranial pathologies and can be utilized during multiple stages of surgery.

Effects of Microvascular Decompression Plus Longitudinal Nerve Sectioning on Recurrent Trigeminal Neuralgia and Investigations of Postoperative Recurrence Causes.

To investigate the causes of recurrent trigeminal neuralgia (RTN) and to evaluate the efficacy of microvascular decompression (MVD) plus longitudinal nerve sectioning (LNS) or LNS only for RTN patients who have undergone multiple procedures. Twenty one patients underwent MVD plus LNS or LNS only at our institute from June 2008 to December 2014. The patients were retrospectively reviewed and analyzed. The following data were collected: age, sex , treatment before surgery, pain severity and distribution, findings during surgery, immediate postoperative BNI (Barrow Neurological Institute score system), final follow-up BNI, complications and associated comorbidities. Vascular compression, arachnoid adhesion and Teflon granulomas were the primary causes of RTN. After MVD plus LNS or LNS only treatments, almost all patients (19/21, 90.5%) reported pain relief after 36.1 months. Of these patients, 15 patients (71.4%) reported being pain-free (BNI score I) and 4 patients (19.1%) reported pain relief (BNI II-III). Two patients reported a pain level of BNI IV. However, almost all patients were left with some degree of numbness. This study certified that vascular compression, arachnoid adhesion and Teflon granulomas were the reasons for RTN. MVD plus LNS or LNS only were both feasible therapeutic options, with good probabilities of success, especially after multiple neurodestructive procedures.

Teflon granulomas mimicking cerebellopontine angle tumors following microvascular decompression

To report two patients with a history of microvascular decompression (MVD) for hemifacial spasm who presented with Teflon granulomas (TG) mimicking cerebellopontine angle (CPA) tumors and to perform a systematic review of the English-language literature. Case series at a single tertiary academic referral center and systematic review. Retrospective chart review with analysis of clinical, radiological, and histopathological findings. Systematic review using PubMed, Embase, MEDLINE, and Web of Science databases. Two patients with large skull base TGs mimicking CPA tumors clinically and radiographically were managed at the authors' institution. The first presented 4 years after MVD with asymmetrical sensorineural hearing loss, multiple progressive cranial neuropathies, and brainstem edema due to a growing TG. Reoperation with resection of the granuloma confirmed a foreign-body reaction consisting of multinucleated giant cells containing intracytoplasmic Teflon particles. The second patient presented 11 years after MVD with asymmetrical sensorineural hearing loss and recurrent hemifacial spasm. No growth was noted over 2 years, and the patient has been managed expectantly. Only one prior case of TG after MVD for hemifacial spasm has been reported in the English literature. TG is a rare complication of MVD for hemifacial spasm. The diagnosis should be suspected in patients presenting with a new-onset enhancing mass of the CPA after MVD, even when performed decades earlier. A thorough clinical and surgical history is critical toward establishing an accurate diagnosis to guide management and prevent unnecessary morbidity. Surgical intervention is not required unless progressive neurologic complications ensue. 4 Laryngoscope, 127:715-719, 2017.

Trigeminal Teflon Granuloma: A Case Report with Operative Nuances

Teflon granuloma is a rare complication of microvascular decompression, and is often misdiagnosed by neurosurgeons. Its etiology is not well understood, although bleeding into the Teflon implant might be a plausible reason. Herein, we present a case report, wherein, previous Teflon implant had migrated forward along the superior aspect of the trigeminal nerve into the Meckel’s cave, causing constant hemi facial pain. Approaching Meckel’s cave from posterior fossa for resection of the Teflon granuloma along with supplementary video, with focus on operative nuances is discussed.

MR Imaging of Teflon Induced Granuloma as a Cause of Recurrent Trigeminal Neuralgia Following Microvascular Decompression

Teflon is an inert material used for microvascular decompression and placed between the trigeminal nerve and offending vessel. Teflon granuloma is considered a less known cause for recurrent facial pain after MVD. Here we report our experience with Teflon ganuloma and its treatment.

A False-Positive FDG Uptake in Teflon Granuloma: A Case Report

Positron emmision tomography (PET) is successfully used to monitor malignancies. Unfortunately it is not tumor specific. We present a case with history of rectum cancer and lentigo maligna who underwent PET-CT which revealed an increased uptake in the larynx. What was first considered as a third primary turned out to be a Teflon granuloma.

Submucosal neoplasms of the laryngeal introitus

The differential diagnosis of endolaryngeal mesenchymal neoplasms includes a wide spectrum of benign and malignant pathologies, which have been rarely photo-documented and assessed as a group. Non-epithelial neoplasms of the endolarynx seen at our centre from 2002 to 2011 (n = 38; 36 treated at our institution) were retrospectively reviewed, with attention to clinical presentation, radiographic imaging, operative management, histology, and pre- and post-operative endoscopy. Submucosal squamous cell carcinomas, mucosal cysts, amyloid and Teflon granulomas were excluded. Twenty-three of a total of 36 patients underwent definitive endoscopic surgical treatment. Supraglottic pathologies included lymphoma, lipoma, neuroendocrine carcinoma, lymphangioma, oncocytoma, haemangioma, synovial cell sarcoma and benign spindle cell neoplasm. Transglottic pathologies included synovial cell sarcoma and granular cell tumour. Glottic pathologies included granular cell tumour, osteoma, rhabdomyoma, rhabdomycosarcoma and myofibroblastic sarcoma. Subglottic pathologies included chondrosarcoma, neurofibroma, adenoid cystic carcinoma and vascular malformation. The site of origin, degree of malignant behaviour and sensitivity to adjuvant treatment determined the course of surgical management, i.e. endolaryngeal versus transcervical, and limited removal versus wider resection.

Coblation removal of laryngeal Teflon granulomas

AbstractLaryngoscope, 2010

Treatment of recurrent trigeminal neuralgia due to Teflon granuloma

Recurrent trigeminal neuralgia after microvascular decompression (MVD) may be due to insufficient decompression, dislocation of the implant to pad the neurovascular contact, or the development of granuloma. Here, we report on our experience with Teflon granuloma including its treatment and histopathological examination. In a series of 200 patients with trigeminal neuralgia MVD was performed with Teflon felt according to Jannetta’s technique. In three patients with recurrent facial pain Teflon granuloma was found to be the cause for recurrence. In each instance, the granuloma was removed for histopathological examination. Mean age at the first procedure was 62.3 years and at the second procedure 66.3 years. Recurrence of pain occurred between 1 and 8.5 years after the first procedure. MRI scans demonstrated local gadolineum enhancement in the cerebellopontine angle, and CT scans showed local calcification. Intraoperatively dense fibrous tissue was found at the site of the Teflon granuloma. Histopathological examination revealed foreign body granuloma with multinuclear giant cells, collagen-rich hyalinized scar tissue, focal hemosiderin depositions, and microcalcifications. The Teflon granuloma was completely removed, and a new Teflon felt was used for re-decompression. Patients were free of pain after the second procedure at a mean of 40.3 months of follow-up. Teflon granuloma is a rare cause for recurrent facial pain after MVD. Small bleeding into the Teflon felt at surgery might trigger its development. A feasible treatment option is surgical re-exploration, nerve preserving removal of the granuloma, and repeat MVD.

Radiologic appearance of chronic parapharyngeal Teflon granuloma

Although Teflon has been used for almost 5 decades to provide tissue augmentation in various surgical indications, including head and neck surgery, its use has significantly declined in the last 2 decades, primarily because of its implication in granuloma formation. Teflon granulomas have been shown to cause false positives on positron emission tomography imaging and have been reported to have a characteristic magnetic resonance imaging (MRI) appearance. We report a patient with a large chronic Teflon granuloma of the parapharyngeal space that caused significant bony erosion of the atlas vertebra. The lesion's MRI signal characteristics were indistinguishable from those of surrounding tissues, while it showed characteristic hyperdensity on computed tomography due to the presence of fluorine atoms within Teflon. As MRI may supersede or replace computed tomography for a number of indications, and as Teflon has been used in large numbers of patients whose records may not always be available, knowledge of these findings has clinical relevance.

An Unusual Presentation of Teflon Granuloma: Case Report and Discussion

For more than 25 years, Teflon was the most commonly used material for injection laryngoplasty. However, the incidence of Teflon granuloma and the consequent deterioration of glottic function ultimately led to the development of other injectable materials, and as a result, Teflon granulomas are no longer frequently encountered. We present a case of Teflon granuloma that was unusual in that (1) a long period of time had elapsed between the injection and the granuloma formation and (2) there was no change in the patient's glottic function.

Teflon laryngeal granuloma presenting as laryngeal cancer on combined positron emission tomography and computed tomography scanning

Positron emission tomography with 18F-fluorodeoxyglucose (18FDG) has been increasingly used in the diagnostic investigation of patients with neoplasms of the head and neck. Positron emission tomography and computed tomography have also proven useful for surveillance of thyroid cancers that no longer concentrate radioiodine. However, certain benign or inflammatory lesions can also accumulate 18F-fluorodeoxyglucose and lead to misdiagnosis. We review and discuss the pitfalls of using positron emission tomography and computed tomography for surveillance of thyroid cancer. We present the case of a 48-year-old woman who was diagnosed with a laryngeal neoplasm on integrated positron emission tomography and computed tomography scanning, after a routine ultrasound demonstrated an enlarged thyroid nodule. On physical examination, she had a laryngeal mass overlying an immobile vocal fold. The mass was biopsied and found to harbour a Teflon granuloma. Positron emission tomography positive Teflon granulomas have previously been reported in the nasopharynx and vocal folds, and should be considered in the differential diagnosis of patients who have undergone prior surgery involving Teflon injection. It is important for otolaryngologists and radiologists to recognise potential causes of false positive positron emission tomography and computed tomography findings, including Teflon granulomas.