Treatment of recurrent lingual nerve end-neuroma: A case report.

A neuroma is a collection of disorganized nerve sprouts emanating from an interruption of axonal continuity, forming within a collagen scar as the nerve attempts to regenerate. Lingual neuroma formation secondary to iatrogenic trauma to the tongue is likely not uncommon; however, we could not find a report in the literature of treatment of a distal tongue end-neuroma treated by resection and implantation into muscle. Here we describe a patient who experienced debilitating chronic tongue pain after excision of a benign mass. After failing conservative management, the patient was taken to the operating room where an end-neuroma of the lingual nerve was identified and successfully treated by excision and burying of the free proximal stump in the mylohyoid muscle. At 17 months postoperatively, she remains pain free without dysesthesias.

Solitary giant neurofibroma of the mental nerve: a trauma-related lesion?

Neurofibroma is a benign neoplasm derived from peripheral nerves whose etiology is still unclear. It may present as a solitary lesion or be associated with other diseases such as neurofibromatosis type I and II syndrome. This paper aims to report an extremely rare case of a solitary giant neurofibroma of the mental nerve whose etiology was related to a local trauma. A 14-year-old female patient presented an extensive left facial mass with a size of 7 × 5 × 4 cm, located between the teeth 33 and 37 in the mandible region. It has begun to grow 3 months after a local trauma. Imaging studies were suggestive of a soft-tissue lesion, with minimal bone changes and maintaining the integrity of the mandibular canal and mental foramen. Histopathological tests showed spindle cells with undulated and hyperchromatic nuclei, and sparse cytoplasm in a stroma composed of dense fibrous connective tissue. Immunohistochemistry revealed positive expression for the proteins S-100 and vimentin, confirming the diagnosis of neurofibroma. The patient underwent surgical removal of the lesion by intraoral approach and evolved with an excellent cosmetic result and no signs of recurrence after 2 years of follow up. We report a rare case of solitary giant neurofibroma whose etiology was related to a local trauma. To our knowledge, this is the first report of a mental nerve neurofibroma. Although the etiology remains unclear, we suggest the investigation of local trauma as a possible etiologic factor for solitary neurofibromas of the jaw.

Gamma knife radiosurgery for trigeminal schwannomas: A systematic review and meta-analysis.

BACKGROUND: Gamma knife radiosurgery (GKRS) has been deemed as the gold standard stereotactic radiosurgery (SRS) mode for the treatment of intracranial tumors, cerebrovascular diseases and brain functional diseases. Our study was aimed to systematically evaluate the efficacy, safety, and complications of gamma knife radiosurgery for trigeminal schwannomas. METHOD: We performed a systematic review and meta-analysis to analyze the clinical outcomes of patients with trigeminal schwannomas treated primarily or adjunctly with GKRS. We searched two databases, Pubmed and Embase, for studies published before January 1, 2021, using GKRS for trigeminal schwannomas. Studies reporting treatment of other schwannomas, or other forms of SRS such as linear accelerator and Cyberknife were excluded to reduce its heterogeneity. RESULTS: Our search achieved 351 studies, of which 35 were assessed for full-text eligibility. 19 studies were included in the meta-analysis. 456 of 504 patients (0.94, 95% CI 0.91-0.96, I2 = 3.02%, p < 0.01) from 18 studies had local control, and 278 of 489 patients (0.63, 95%CI 0.48-0.78, I2 = 88.75%, p < 0.01) from 16 studies experienced tumor regression or disappearance. 231 of 499 patients (0.50, 95% CI 0.37-0.62; I2 = 83.89%, P < 0.01) from 17 studies had clinical symptoms improved. There was no significant difference in tumor control between those treated with GKRS as either primary treatment or adjuvant to surgery(p = 0.390). CONCLUSION: GKRS is an efficacious primary and adjuvant method of treating trigeminal schwannomas, with reliable tumor control rates. Randomized controlled trials are needed to further and comprehensively evaluate the benefit-to-risk ratio of gamma knife radiosurgery.

["An Italian Court recognizes the occupational origin of a trigeminal neuroma in a mobile telephone user: a case-study of the complex relationships between science and laws"]. / Una Corte italiana riconosce l'origine professionale di un neurinoma del trigemino in un utilizzatore di telefoni mobili: un esempio concreto dei complessi rapporti tra scienza e diritto.

BACKGROUND: Scientific knowledge is essential for the resolution of disputes in law and administrative applications (such as toxic tort litigation and workers' compensation) and provides essential input for public policy decisions. There are no socially agreed-upon rules for the application of this knowledge except in the law. On a practical level, the legal system lacks the ability to assess the validity of scientific knowledge that can be used as evidence and therefore relies heavily on expert opinion. A key issue is how to ensure that professionals in any field provide judges with sound advice, based on relevant and reliable scientific evidence. The search for solutions to this problem seems particularly urgent in Italy, a country where a number of unprecedented verdicts of guilt have been pronounced in trials involving personal injuries from exposure to electromagnetic fields. OBJECTIVES AND METHODS: An Italian Court has recently recognized the occupational origin of a trigeminal neuroma in a mobile telephone user, and ordered the Italian Workers' Compensation Authority (INAIL) to award the applicant compensation for a high degree (80%) of permanent disability. We describe and discuss the salient aspects of this sentence as a case-study in the framework of the use (and misuse) of scientific evidence in toxic-tort litigations. RESULTS: Based on the motivations of the verdict, it appears that the judge relied on seriously flawed expert testimonies. The "experts" who served in this particular trial were clearly inexperienced in forensic epidemiology in general, as well as in the topic at hand. Selective overviews of scientific evidence concerning cancer risks from mobile phone use were provided, along with misleading interpretations of findings from relevant epidemiologic studies (including the dismissal of the Interphone study results on the grounds of purported bias resulting from industry funding). The necessary requirements to proceed to causal inferences at individual level were not taken into account and inappropriate methods to derive estimates of personal risk were used. CONCLUSIONS: A comprehensive strategy to improve the quality of expert witness testimonies in legal proceedings and promote just and equitable verdicts is urgently needed in Italy. Contrary to other countries, such as the United States or the United Kingdom, legal standards for expert testimony, such as preliminary assessment of scientific evidence admissibility and qualification requirements for professionals acting as experts in the courtroom, are lacking in our country. In this and similar contexts, recommendations issued by professional associations (including EBEA and BEMS) could play a role of paramount importance. As examples, we refer to the guidelines recently endorsed by the UK General Medical Council and the American Academy of Pediatrics.

Traumatic neuroma of the infraorbital nerve subsequent to inferomedial orbital decompression for Graves' orbitopathy.

PURPOSE: To present and discuss the occurrence of a traumatic neuroma subsequent to inferomedial orbital decompression surgery in Graves' orbitopathy. METHODS: Case report. RESULTS: Approximately 1 month after surgery, a patient who underwent bilateral rehabilitative inferomedial orbital decompression developed a mass with clinical and radiologic characteristics compatible with a traumatic neuroma of the left infraorbital nerve. The lesion, which was thought to be the result of unnoticed nerve trauma at the time of surgical dissection of the infraorbital canal, remained stable in shape and other imaging characteristics during the 39-month follow-up period. Symptoms of trigeminal neuralgia could be only partially controlled with medical therapy (oral pregabalin 75 mg 3 times daily). CONCLUSIONS: The second branch of the trigeminal nerve may be damaged in the course of orbital floor removal decompression for Graves' orbitopathy. This may potentially induce the formation of traumatic or amputation neuromas. Such lesions should be included in the potential complications of decompressions when counseling patients about to undergo this type of surgery, as they are difficult to treat and may cause persistent and disabling pain.

Factors predicting growth of vestibular schwannoma in neurofibromatosis type 2.

We retrospectively reviewed characteristics of patients with neurofibromatosis type 2 to identify factors predicting further growth of bilateral vestibular schwannomas. Subjects comprised 27 neurofibromatosis type 2 patients with 54 vestibular schwannomas, followed for 24-204 months (mean, 86 months). This study investigated factors predictive of vestibular schwannoma growth in neurofibromatosis type 2. Features distinguishing actively growing from quiescent VS were determined for untreated course (28 vestibular schwannomas) and posttreatment course (including either resection or radiosurgery; 33 vestibular schwannomas). A general estimation equation was used to identify factors affecting tumor growth. During the untreated course, 19 vestibular schwannomas showed growth and 9 vestibular schwannomas were stable. No factors predictive of growth were shown. During the posttreatment course (23 surgical resections, ten radiosurgeries), ten treatments were followed by growth and 23 were followed by stability, with growth showing an association with onset at an early age (p = 0.007). Multivariate analysis identified no factors predictive of growth. After treatment, close follow-up is warranted for patients with onset at an early age.

Pathology of the olfactory nerve.

The olfactory system and especially the olfactory bulb (OB) as the first relay in the olfactory system represent highly plastic structures. For example, OB volume partly reflects the degree of afferent neural activity. Research indicates that smell deficits leading to a reduced sensory input result in structural changes at the level of the OB. Reduced OB volumes also may be considered characteristic of parosmia. Apart from discussing the clinical implications of these findings, the radiologic basics for assessment of olfactory-eloquent structures are addressed in detail.

Pathology of the ocular motor nerves III, IV, and VI.

The ocular motor nerves supply motor fibers to the extraocular muscles of the globe and levator muscle of the eyelid and parasympathetic pupillomotor fibers to the ciliary ganglion. Lesions are classified according to the anatomic location at which they occur: nuclear, fascicular, cisternal, cavernous, or orbital apex. The course each nerve follows influences the sites at which it is most vulnerable to damage and the pathologies to which it is exposed. Cranial nerve palsies frequently are associated with neurologic deficits that may assist in localizing the lesion anatomically. This article provides an overview of the pathology of the ocular motor nerves.

Pathology of the trigeminal nerve.

Imaging of the trigeminal nerve requires a thorough understanding of its anatomy and function, clinical symptoms related to malfunction, and its key pathologies. Because of the nerve's long course from the brainstem nuclei to the peripheral branches, MR imaging and CT studies have to cover a large anatomic area while providing high-resolution images. Although MR imaging has almost completely replaced CT as the diagnostic modality of choice for investigating trigeminal neuropathy, CT still plays a role in the assessment of skull base foramina and facial skeleton. In this article, the clinical, radiologic, and pathologic features of the most common conditions causing trigeminal nerve dysfunction at each specific anatomic level are discussed.

Pathology of the facial nerve.

A good examination in facial nerve imaging (CT or MR imaging) depends on a good knowledge of anatomy. Two clinical situations must be considered: imaging of patients with or without facial palsy. CT and MR imaging are very useful when the symptoms are atypical or progressive: MR imaging gives very good information about the facial nerve inflammation but may also discover a schwannoma, a hemangioma, a meningioma, or a primitive or secondary cholesteatoma. In malignant tumors of the parotid gland, a study of the fallopian canal must always be performed to delineate an extension in the mastoid, tympanic, or intrameatic parts. In some rare cases, a metastasis in the temporal bone may occur, especially in the region of the geniculate ganglion. Particular attention must be paid to children with facial palsy, considering the possibility of a histiocytosis or metastasis of a neuroblastoma.

Pathology of the vestibulocochlear nerve.

Imaging of the vestibulocochlear nerve has evolved dramatically over the past few decades. The imaging specialist now is involved in the diagnosis of far more diagnostic entities than ever before. With this increased involvement comes the responsibility to increase collective knowledge regarding the pathophysiology of these diagnostic entities. This article is organized in a conventional way and covers congenital deformity of the internal auditory canal, neoplastic and pseudoneoplastic lesions, with special detailed emphasis on schwannoma of the eight cranial nerves (acoustic neuroma), nonneoplastic IAC/CPA pathology, including vascular loops, and numerous additional differential diagnostic entities, with particular emphasis on non-neoplastic meningeal disease. Lesions of the auditory pathway and an overview of cochlear implant surgery are also included in this discussion.

Traumatic neuroma of the inferior alveolar nerve: a case report.

Traumatic neuromas are rare entities which characteristically arise subsequently to surgery and are usually accompanied by pain, typically neuralgic. We present an unusual case of an intraosseous traumatic neuroma of the inferior alveolar nerve following tooth extraction. A 56-year-old man consulted for paresthesias and hyperesthesia in the left mandibular region following extraction of the left mandibular third molar (#38). The panoramic radiograph revealed a radiolucent lesion in the inferior alveolar nerve canal, and CT demonstrated the existence of a mass within the canal, producing widening of the same. Nerve-sparing excisional biopsy was performed. Histopathology and immunohistochemistry were consistent with traumatic neuroma of the left inferior alveolar nerve. After 3 years of follow-up, the patient is asymptomatic and there are no signs of recurrence.

Multiple cranial nerve schwannomas and meningiomas as a hallmark sign of neurofibromatosis type 2 in a child.

Halefoglu AM. Multiple cranial nerve schwannomas and meningiomas as a hallmark sign of neurofibromatosis type 2 in a child. Turk J Pediatr 2018; 60: 107-110. Neurofibromatosis type 2 is a rarely encountered autosomal dominant disorder manifesting with typical radiological findings. These patients have a predilection for development of benign tumors in the central nervous system. Although the presenting symptom is most commonly hearing loss due to acoustic schwannomas, symptoms emanating from other cranial tumors are not uncommon. Herein, we described a 16-year-old male patient presented with multiple meningiomas and cranial nerve schwannomas revealed by magnetic resonance imaging. He fulfilled the diagnostic criteria of neurofibromatosis type 2 and underwent treatment. We emphasized the role of radiology in the early diagnosis of this inherited disorder in order to provide a better prognosis.

Spinal accessory nerve meningioma in a paediatric patient: case report.

Accessory nerve meningiomas are exceedingly rare. We present a case of a nine-year-old patient with neurofibromatosis type 2 who had radiologic evidence of spinal cord compression from an upper cervical/foramen magnum lesion. He was asymptomatic from this lesion, but it progressed in size. The tumor was resected and histologic investigation revealed frequent tight whorls and psammoma bodies consistent with meningioma. To the authors' knowledge, this is the first reported spinal accessory nerve meningioma in a pediatric patient.

Distribution of nonvestibular cranial nerve schwannomas in neurofibromatosis 2.

OBJECTIVE: To describe the prevalence and location of cranial nerve schwannomas, other than bilateral vestibular schwannoma, in patients with neurofibromatosis 2 (NF2). The NF2 Natural History Consortium prospectively gathered cranial magnetic resonance imaging for 83 patients across 3 annual evaluations. The time between the first and last evaluation was approximately 3 years. RESULTS: Forty-two patients (51%) had nonvestibular cranial nerve schwannomas (NVSs). Of these, 25 (60%) also had cranial meningiomas. Twenty-one of those without NVS (25% of 83) had at least 1 meningioma. The average size of the NVS was 0.4 cubic centimeters. Overall, there was no significant change in NVS size from Year 1 to Year 3 or from Year 1 to Year 2. The most common locations of the NVS were occulomotor and trigeminal. A family history of NF2 did not predict NVS location or growth. CONCLUSION: Nonvestibular cranial nerve schwannoma usually affect cranial nerves III and V, as was the case in our NF2 sample. Fortunately, neuropathies associated with these tumors are rare. In contrast, lower cranial nerve schwannomas, although also rare, are associated with swallowing difficulty, aspiration, and other sequelae.

[Cell Phones and Risk of brain and acoustic nerve tumours: the French INTERPHONE case-control study]. / Téléphone mobile, risque de tumeurs cérébrales et du nerf vestibuloacoustique: l'étude cas-témoins INTERPHONE en France.

BACKGROUND: Use of cell phones has increased dramatically since 1992 when they were first introduced in France. Certain electromagnetic fields (at extremely low frequency) have been recognized as possibly carcinogenic by the International Agency for Research on Cancer. Given the use of radiofrequency technology in cell phones, the rapid increase in the number of cell phones has generated concerns about the existence of a potential health hazard. To evaluate the relationship between the use of cell phones and the development of tumors of the head, a multicentric international study (INTERPHONE), coordinated by the International Agency for Research on Cancer, was carried out in 13 countries. This publication reports the results of the French part of the INTERPHONE study. METHODS: INTERPHONE is a case-control study focused on tumors of the brain and central nervous system: gliomas, meningiomas and neuromas of cranial nerves. Eligible cases were men and women, residents of Paris or Lyon, aged 30-59, newly diagnosed with a first primary tumor between February 2001 and August 2003. The diagnoses were all either histologically confirmed or based upon unequivocal radiological images. Controls were matched for gender, age (+/-5 years) and place of residence. They were randomly drawn from electoral rolls. Detailed information was collected for all subjects during a computer-assisted face-to-face interview. Conditional logistic regression was used to estimate the odds ratio (OR) for an association between the use of cell phones and risk of each type of cancer. RESULTS: Regular cell phone use was not associated with an increased risk of neuroma (OR=0,92; 95% confidence interval=[0.53-1.59]), meningioma (OR=0,74; 95% confidence interval=[0.43-1.28]) or glioma (OR=1.15; 95% confidence interval=[0.65-2.05]). Although these results are not statistically significant, a general tendency was observed for an increased risk of glioma among the heaviest users: long-term users, heavy users, users with the largest numbers of telephones. CONCLUSION: No significant increased risk for glioma, meningioma or neuroma was observed among cell phone users participating in Interphone. The statistical power of the study is limited, however. Our results, suggesting the possibility of an increased risk among the heaviest users, therefore need to be verified in the international INTERPHONE analyses.

Combined isolated trigeminal and facial neuropathies from perineural invasion by squamous cell carcinoma: A case series and review of the literature.

Perineural invasion is a targeted cellular proliferation guided by neurotrophins, rather than a simple diffusion of tumor in a path of least resistance. Invasion of cranial nerves by squamous cell carcinoma can represent an important diagnostic dilemma. It commonly presents as a distinct clinical neurological syndrome of combined isolated trigeminal and facial neuropathies. The focal cancer source may have been overlooked or remain occult. This case series illustrates diverse clinical presentations and neuroimaging challenges in four patients with squamous cell carcinoma of the cranial nerves. Anatomical pathways linking the trigeminal and facial nerves are reviewed, with emphasis on the auriculotemporal and pterygopalatine nerves. A successful neuroimaging strategy requires a targeted multimodality analysis of specific anatomical loci at the base of the skull. Attention must be directed to subtle radiological findings, such as obliteration of fat planes and linear enhancement along nerve branches, rather than bulky tumor tissue or bony invasion. Despite advances in microsurgical dissection and targeted radiotherapy, recovery of established neuropathic deficits is not expected. The prognosis remains poor in cases of advanced disease, emphasizing the importance early diagnosis by clinical acumen and focused neuroimaging.