Abducens nerve palsy is the most common ocular motor nerve palsy, and its possible aetiologies are numerous and diverse. Primary malignancy rarely occurs in the middle ear, with most cases associated with long-standing ear discharge and peak age of presentation in the sixties. We report a rare case of a 64-year-old male who presented with right abducens nerve palsy, which led to the diagnosis of primary squamous cell carcinoma of the right middle ear, and to our knowledge, this has not been reported previously in English literature.

UNASSIGNED: We report a case of cerebral venous sinus thrombosis (CVST) that presented with bilateral optic disc swelling and diplopia in the absence of headaches.
UNASSIGNED: A 54-year-old woman with no relevant medical history presented with a 2-week history of diplopia and no loss of visual acuity in each eye. Eye movements revealed bilateral abduction deficits, and fundoscopic examination revealed bilateral optic disc swelling. Non-contrast computed tomography of the head showed no abnormalities. Magnetic resonance venography revealed the absence of flow in the superior sagittal and left transverse sinuses as a consequence of thrombosis. The patient was diagnosed with intracranial hypertension associated with abducens nerve palsies secondary to CVST and was initiated on anticoagulant therapy. CVST can lead to stroke even in younger individuals.
UNASSIGNED: CVST should be considered in differential diagnosis when bilateral papilledema and abducens nerve palsies are present, even in the absence of headache or other neurological findings.

Numerous neurological manifestations associated with COVID-19 have been reported. However, abducens nerve palsy (ANP) associated with COVID-19 is very rare and mostly related to accompanying respiratory symptoms. Here we present a 29-year-old woman with unilateral ANP manifesting with diplopia and positive SARS-CoV-2 S antibodies, which were checked later. On admission, she had signs of viral pneumonia in thorax CT without any respiratory symptoms. Her cranial neuroimaging revealed no abnormality. Following treatment with favipiravir 2x1600 mg loading dose and then 2x600mg daily maintenance, dexamethasone 8 mg/day and enoxaparin 6000 IU/day, her CT findings recovered completely whereas her ANP only partially resolved. One week after the end of COVID-19 treatment, she also developed Herpes simplex keratitis which was successfully treated with valacyclovir. It should be kept in mind that isolated abducens nerve palsy may be the only finding of COVID-19 cases without any respiratory symptoms.

Herpes zoster ophthalmicus (HZO) is a condition resulting from the reactivation of dormant varicella zoster virus within the sensory nerve ganglion in the ophthalmic branch of the trigeminal nerve. The tell-tale rash along one side of the nerve tract accompanied by pain, a burning sensation, and itching alerts health practitioners on the right path to diagnosis. Conversely, HZO can present with other rarer complications such as intraocular and extraocular manifestations. This case report deals with a seemingly healthy 45-year-old female who developed left abducens nerve palsy within one week of developing a vesicular rash on the same side. Curiously, those afflicted are usually of an advanced age or suffer from an immunocompromised state; this patient however suffered from no other comorbidities nor did she report having been in contact with anyone of a similar affliction. In this case, the classical treatment regime of antivirals and corticosteroids resulted in the complete resolution of the infection and the return of full ocular function. Being able to recognize and appreciate these typical and atypical signs and symptoms of HZO can aid in the further propagation of good outcomes and timely resolutions.

Gradenigo\'s syndrome (GS) is a rare entity characterized by otitis media, pain in the trigeminal nerve distribution and abducens nerve palsy. The classic triad is uncommon, making the diagnostic workup challenging. Specifically, the diagnostic approach includes medical history, a complete otorhinolaryngological examination, a pure-tone audiogram and radiological investigation such as contrast-enhanced computed tomography scan and magnetic resonance imaging of head and neck. Broad-spectrum antibiotics are the first-line treatment, such as intravenous (IV) ceftriaxone and IV metronidazole. Here, we present the case of a 71-year-old man with a previous history of otitis media and poorly controlled type 2 diabetes mellitus. He presented to our attention with facial pain, left hemilarynx paralysis, dysphagia and otorrhea. The patient was treated with broad-spectrum antibiotics without any clinical improvement. Imaging evaluations demonstrated the presence of wide and poorly defined pathological material with epicenter in the masticatory space, involving all nearby structures. The patient underwent multiple biopsies without obtaining a definitive tissue diagnosis of neoplasia. After 2 months, the patient developed delayed VI cranial nerve palsy, providing evidence of GS. Although incomplete, GS has been described in the literature; however, none of the cases exhibited a latent abducent deficit. To the best of our knowledge, this is the only case with a delayed onset of abducens nerve palsy.

The three classic symptoms of carotid cavernous fistula (CCF) are pulsating exophthalmos, bruit and conjunctival chemosis. Here, we present a clinical case of isolated abducens nerve palsy due to a high-flow CCF in an 84-year-old woman, without the typical congestive orbito-ocular features. It was a diagnostic challenge because, for patients older than 50 years with cardiovascular risk factors, ischaemic mononeuropathy is the most frequent aetiology. This case illustrates the least common type of CCF that can be easily misdiagnosed. Physicians should consider fistula as a possible diagnosis in a patient with isolated abducens nerve palsy even without the classic triad.

We report the case of a male in his 50s with a history of smoking admitted to our hospital for three transient recurrent episodes of less than 60 min of cheiro-oral paresthesias and binocular horizontal diplopia with convergent strabismus. On admission, his neurological examination was normal. Cerebral magnetic resonance imaging showed no cerebral lesion. Computed tomography angiography showed a sub-occlusive right carotid bulb atherosclerotic stenosis, the absence of abnormality of the subclavian arteries and the origin of the vertebral arteries, and no stenosis of the basilar artery or posterior cerebral arteries. Routine blood tests were normal with glycated hemoglobin of 6.5%. The patient underwent right carotid endarterectomy. One year after carotid endarterectomy, the patient has had no other cerebrovascular events.

This case report details the occurrence of bilateral sequential abducens nerve palsy in a previously healthy 42-year-old woman two days after receiving her first dose of the Pfizer-BioNTech COVID-19 vaccine (BNT162b2). Despite the widespread global administration of COVID-19 vaccines, instances of abducens palsy following vaccination are limited in the available literature. Considering the temporal association between vaccination and symptom onset, the absence of underlying medical conditions predisposing to such neurological manifestations, normal brain imaging results, the occurrence of other cranial palsies post-vaccination, and analogous occurrences after different vaccinations, we propose a plausible connection between the patient\'s abducens palsy and the COVID-19 vaccination. Our findings contribute to the growing body of evidence regarding the side effects and safety profile of COVID-19 vaccines. Importantly, the resolution of symptoms with conservative management and the uneventful administration of the second vaccine dose suggest that the observed abducens palsy may be a transient and isolated reaction.

Mycoplasma pneumoniae is a self-propagating microorganism that commonly causes respiratory tract infections. It can also cause a variety of extrapulmonary symptoms with or independently of respiratory symptoms, such as skin lesions, arthralgia, myalgia, hemolysis, cardiac lesions, gastrointestinal symptoms, and central nervous system lesions, which are rare manifestations reported in approximately 0.1% of cases. In this study, we present a unique case of Mycoplasma-related abducens nerve palsy, polyarthritis, and erythema multiforme without respiratory disease. The patient was a 69-year-old woman who presented to our hospital with a skin rash, fever, arthralgia, and diplopia without respiratory symptoms. Brain magnetic resonance imaging showed optic neuritis on the right side, suggesting the diplopia was caused by right abducens nerve palsy. However, the etiologies of abducens nerve palsy were not revealed by the physical examination, blood biochemistry tests, or bacteriological examinations, including the cerebrospinal fluid examination obtained at admission. Mycoplasma infection was suspected from erythema multiforme revealed by a skin biopsy and polyarthralgia, and it was finally diagnosed according to elevated Mycoplasma particle agglutination (PA) antibodies in paired serum. Though minocycline did not improve her diplopia, the daily administration of 30 mg of prednisolone gradually improved her symptoms, and the Mycoplasma PA antibody titer, which was regularly measured in the clinical course, also decreased, suggesting a relationship between Mycoplasma infection and abducens nerve palsy. This is the first case of isolated abducens nerve palsy, which was reported as the only central neurological symptom in an adult patient with Mycoplasma infection. The mechanism or pathogenesis of CNS manifestations caused by Mycoplasma pneumoniae remains to be elucidated, and further investigation is needed. Hence, Mycoplasma infection is a common disease. Clinicians should be aware of the diverse manifestations, including abducens nerve palsy, of Mycoplasma infection and should consider Mycoplasma infection even in the absence of typical respiratory symptoms.

Cranial nerve palsies can be presenting signs of intracranial aneurysms. There is a classic pairing between an aneurysmal vessel and adjacent nerves leading to cranial neuropathy. Isolated abducens nerve palsy can be a localizing sign of an unruptured vertebrobasilar circulation aneurysm. Aneurysms involving Anterior Inferior Cerebellar Artery (AICA) and Posterior Inferior Cerebellar Artery (PICA) have been reported to be associated with abducens nerve palsy. The symptoms in unruptured aneurysms are due to the mass effect on adjacent neurovascular structures. Most of the abducens nerve palsy resolves following microsurgical clipping. Here, we present a rare case of an unruptured Posterior Cerebral Artery (PCA) aneurysm presenting with abducens nerve palsy and diplopia associated with contralateral hemianopsia which markedly improved following endovascular coil embolization.