Intracranial aneurysms and abducent nerve palsy.

Background: Cranial nerve (CN) palsy may manifest as an initial presentation of intracranial aneurysms or due to the treatment. The literature reveals a paucity of studies addressing the involvement of the 6th CN in the presentation of cerebral aneurysms. Methods: Clinical patient data, aneurysmal characteristics, and CN 6th palsy outcome were retrospectively reviewed and analyzed. Results: Out of 1311 cases analyzed, a total of 12 cases were identified as having CN 6th palsy at the presentation. Eight out of the 12 were found in the unruptured aneurysm in the cavernous segment of the internal carotid artery (ICA). The other four cases of CN 6th palsy were found in association with ruptured aneurysms located exclusively at the posterior inferior cerebellar artery (PICA). For the full functional recovery of the CN 6th palsy, there was 50% documented full recovery in the eight cases of the unruptured cavernous ICA aneurysm. On the other hand, all four patients with ruptured PICA aneurysms have a full recovery of CN 6th palsy. The duration for recovery for CN palsy ranges from 1 to 5 months. Conclusion: The association between intracranial aneurysms and CN 6th palsy at presentation may suggest distinct patterns related to aneurysmal location and size. The abducent nerve palsy can be linked to unruptured cavernous ICA and ruptured PICA aneurysms. The recovery of CN 6th palsy may be influenced by aneurysm size, rupture status, location, and treatment modality.

Acupuncture for abducens nerve palsy after radiochemotherapy: a CARE-compliant case report.

BACKGROUND: Delayed abducens nerve palsy after chemoradiotherapy for nasopharyngeal carcinoma (NPC) is often accompanied by ocular ischemia and cranial nerve damage, thereby increasing the risk of conventional strabismus surgery. Therefore, patients often prefer conservative treatment. Herein we report a case of acupuncture for delayed abducens nerve palsy after chemoradiotherapy for NPC. CASE PRESENTATION: A 39-year-old patient who previously received chemotherapy and radiotherapy for NPC developed a unilateral abducens nerve palsy with numbness in the face and stiffness in the neck muscles after six years. Based on magnetic resonance imaging (MRI), medical history, and physical examination, he was diagnosed with abducens nerve palsy after chemoradiotherapy. The acupuncture treatment regimen was mainly based on periocular electroacupuncture, supplemented with wheat grain moxibustion and warming needle moxibustion, which were performed three times a week. After one month with a total of 17 acupuncture sessions, the patient's affected eye abduction function recovered completely. Facial sensory abnormalities and neck stiffness also improved significantly. Follow-up at two months reported no recurrence. CONCLUSION: Acupuncture may be a conservative treatment option for patients with abducens nerve palsy after chemoradiotherapy.

An Unusual Case of Acute Confusion in an Elderly Man: Pituitary Apoplexy With Lateral Rectus Palsy.

Often, the provisional diagnosis for an elderly patient who arrives at the hospital with confusion is presumed to be delirium stemming from confusion usually caused by an infectious cause. The famous mnemonic PINCH ME signifies the ruling out of pain, infection (that usually has a urinary cause), constipation, dehydration, medication (particularly narcotics), and the environment (factors triggering confusion in a patient with a background of dementia). However, we report a rare case of sudden confusion in an elderly male with no previous history of cognitive impairment. This is the first ever reported case to the best of our knowledge of a patient that presented with sudden confusion, impaired extraocular mobility, and spontaneous cranial hemorrhage that was ultimately determined to be due to a hypothalamic and/or a pituitary cause. It signifies a need for prompt evaluation to arrive at an early diagnosis. Additionally, we hope this case report would serve as a guide to look beyond the current mnemonic of PINCH ME and instead to a new mnemonic of 'PINCH ME HOT' where the latter most mnemonic connotes the need to look at a hypothalamic/pituitary, ocular, or traumatic origin for the delirium.

Vertebrobasilar Dolichoectasia as a Rare Cause of Simultaneous Abducens and Vestibulocochlear Nerve Symptoms: A Case Report and Literature Review.

Vertebrobasilar dolichoectasia (VBD) can lead to cranial nerve symptoms. However, multiple cranial nerve symptoms associated with VBD in one case remain extremely rare. We here present the case of a 33-year-old male with VBD diagnosed by multimodality imaging, who developed simultaneous abducens and vestibulocochlear nerve symptoms and subsequently improved after blood pressure control treatment. To our knowledge, this is the first report of such a vascular disorder resulting in simultaneous symptoms of the abducens and vestibulocochlear nerves. This study highlights that such a vascular anomaly should be considered when cranial nerve symptom is encountered, especially when multiple cranial nerves involved. Meanwhile, radiological evalurrrrrrrrrrrrrrrrrrration of such neurovascular conflict using three-dimensional constructive interference in steady-state imaging is recommended.

Aberrant Abducent Nerve During Microvascular Decompression for Trigeminal Neuralgiass.

BACKGROUND: Microvascular decompression (MVD) is a commonly performed procedure to treat trigeminal neuralgia and hemifacial spasm. Knowledge of the variable anatomy of the cerebellopontine angle is crucial to avoid injury to cranial nerves. CASE DESCRIPTION: A 76-year-old lady with right V1 (ophthalmic division of the trigeminal nerve) and V2 (maxillary division of the trigeminal nerve) trigeminal neuralgia, refractory to medical treatment, underwent elective MVD. Intraoperatively, a distorted course of the cisternal component of the abducent nerve was noticed, caused by an ectatic anterior inferior cerebellar artery. Careful mobilization of the offending vessel to decompress the trigeminal nerve was carried out; however, abducent nerve decompression was not attempted since its function was not compromised. Facial pain resolved postoperatively without new diplopia. CONCLUSIONS: Careful review of imaging before surgery is recommended in order to preempt such unusual anatomic variations.

Surgical Treatment of Spontaneous Internal Carotid Artery Dissection with Abducent Nerve Palsy: Case Report and Review of Literature.

BACKGROUND: Sixth-nerve palsy often develops as a result of trauma, neoplasm, or vascular disease affecting the pons. Less commonly, this palsy can be caused by pathology of the internal carotid artery in the cavernous sinus region. Here, we describe a rare case of spontaneous dissection of the internal carotid artery in the cavernous sinus accompanied by acute sixth nerve palsy that was successfully treated with surgery. CASE DESCRIPTION: An 18-year-old man presented suddenly and spontaneously with isolated abducent nerve palsy. His magnetic resonance angiography identified a dissection of the right internal carotid artery in the cavernous sinus. We successfully treated it with high-flow bypass and ligation of the internal carotid artery (ICA). CONCLUSIONS: Intracavernous ICA dissection is a possible cause of sixth nerve palsy. While most cases likely result from compromised arterial blood supply to the affected nerve, compression of the cranial nerves by the expanded artery can occur in some cases. Surgical treatment is a safe and effective option for relieving nerve compression after intracavernous ICA dissection.

Magnetic resonance imaging findings of isolated abducent nerve palsy induced by vascular compression of vertebrobasilar dolichoectasia.

If the origin of isolated abducent nerve palsy cannot be found on neuroradiological examinations, diabetes mellitus is known as a probable cause; however, some cases show no potential causes of isolated abducent nerve palsy. Here, we report a 74-year-old male who suffered from diplopia due to isolated left abducent nerve palsy. Magnetic resonance angiography and fast imaging employing steady-state acquisition imaging clearly showed a dolichoectasic vertebrobasilar artery compressing the left abducent nerve upward and outward. There were no abnormal lesions in the brain stem, cavernous sinus, or orbital cavity. Laboratory data showed no abnormal findings. We concluded that neurovascular compression of the left abducent nerve might cause isolated left abducent nerve palsy. We observed him without surgical treatment considering his general condition with angina pectoris and old age. His symptom due to the left abducent nerve palsy persisted. From previous reports, conservative treatment could not improve abducent nerve palsy. Microvascular decompression should be considered for abducent nerve palsy due to vascular compression if patients are young, and their general condition is good. We also discuss interesting characteristics with a review of the literature.

Bilateral Abducent Nerve Palsy After Neck Trauma: A Case Report.

INTRODUCTION: The abducent nucleus is located in the upper part of the rhomboid fossa beneath the fourth ventricle in the caudal portion of the pons. The abducent nerve courses from its nucleus, to innervate the lateral rectus muscle. This nerve has the longest subarachnoid course of all the cranial nerves, it is the cranial nerve most vulnerable to trauma. It has been reported that 1% to 2.7% of all head injuries are followed by unilateral abducent palsy, but bilateral abducent nerve palsy is extremely rare. CASE PRESENTATION: A 65-year-old woman presented to the emergency department following a motor vehicle accident. A neurological assessment showed the patient's Glascow coma scale (GCS) to be 15. She complained of double vision, and we found lateral gaze palsy in both eyes. A hangman fracture type IIA (C2 fracture with posterior ligamentous C1 - C2 distraction) was found on the cervical CT scan. A three-month follow-up of the patient showed complete recovery of the abducent nerve. CONCLUSIONS: Conservative treatment is usually recommended for traumatic bilateral abducent nerve palsy. Our patient recovered from this condition after three months without any remaining neurological deficit, a very rare outcome in a rare case.

Bilateral Abducent Palsy in Leptospirosis- An Eye Opener to a Rare Neuro Ocular Manifestation: A Case Report.

Leptospirosis, a disease of great significance in tropical countries, presents commonly as a biphasic illness with acute febrile episode in the first phase followed by a brief afebrile period and then by the second phase of fever with or without jaundice and renal failure. However, it has varied manifestations and unusual clinical features ascribed to immunological phenomena can occur due to the additional involvement of pulmonary, cardiovascular, and neurological systems. Among the various neurological features, aseptic meningitis is the most common myeloradiculopathy, myelopathy, cerebellar dysfunction, transverse myelitis, Guillain-Barre syndrome, optic neuritis, peripheral neuropathy hare also described. Cranial neuropathy involving facial nerve is a rare, but known neurological manifestation. Sixth nerve palsy in neuroleptospirosis has so far not been reported. We hereby present the occurrence of bilateral abducent nerve palsy in a patient with leptospirosis.

Abducent nerve palsy treated by microvascular decompression: a case report and review of the literature.

Too few cases of isolated abducent nerve palsy caused by neurovascular compression syndrome have been reported. We here report on a case of abducent nerve palsy caused by neurovascular compression syndrome that was successfully treated by microvascular decompression (MVD). A 46-year-old male presented with a 6-month history of right-sided persistent abducent nerve palsy. High-resolution magnetic resonance imaging revealed a neurovascular contact of the vertebral artery with the right abducent nerve. MVD was performed via a retrosigmoid craniotomy, with remarkable improvement of the palsy. Our report suggests that MVD might be considered as an optional treatment if the symptoms progress or persist.

Detection of third and sixth cranial nerve palsies with a novel method for eye tracking while watching a short film clip.

OBJECT: Automated eye movement tracking may provide clues to nervous system function at many levels. Spatial calibration of the eye tracking device requires the subject to have relatively intact ocular motility that implies function of cranial nerves (CNs) III (oculomotor), IV (trochlear), and VI (abducent) and their associated nuclei, along with the multiple regions of the brain imparting cognition and volition. The authors have developed a technique for eye tracking that uses temporal rather than spatial calibration, enabling detection of impaired ability to move the pupil relative to normal (neurologically healthy) control volunteers. This work was performed to demonstrate that this technique may detect CN palsies related to brain compression and to provide insight into how the technique may be of value for evaluating neuropathological conditions associated with CN palsy, such as hydrocephalus or acute mass effect. METHODS: The authors recorded subjects' eye movements by using an Eyelink 1000 eye tracker sampling at 500 Hz over 200 seconds while the subject viewed a music video playing inside an aperture on a computer monitor. The aperture moved in a rectangular pattern over a fixed time period. This technique was used to assess ocular motility in 157 neurologically healthy control subjects and 12 patients with either clinical CN III or VI palsy confirmed by neuro-ophthalmological examination, or surgically treatable pathological conditions potentially impacting these nerves. The authors compared the ratio of vertical to horizontal eye movement (height/width defined as aspect ratio) in normal and test subjects. RESULTS: In 157 normal controls, the aspect ratio (height/width) for the left eye had a mean value ± SD of 1.0117 ± 0.0706. For the right eye, the aspect ratio had a mean of 1.0077 ± 0.0679 in these 157 subjects. There was no difference between sexes or ages. A patient with known CN VI palsy had a significantly increased aspect ratio (1.39), whereas 2 patients with known CN III palsy had significantly decreased ratios of 0.19 and 0.06, respectively. Three patients with surgically treatable pathological conditions impacting CN VI, such as infratentorial mass effect or hydrocephalus, had significantly increased ratios (1.84, 1.44, and 1.34, respectively) relative to normal controls, and 6 patients with supratentorial mass effect had significantly decreased ratios (0.27, 0.53, 0.62, 0.45, 0.49, and 0.41, respectively). These alterations in eye tracking all reverted to normal ranges after surgical treatment of underlying pathological conditions in these 9 neurosurgical cases. CONCLUSIONS: This proof of concept series of cases suggests that the use of eye tracking to detect CN palsy while the patient watches television or its equivalent represents a new capacity for this technology. It may provide a new tool for the assessment of multiple CNS functions that can potentially be useful in the assessment of awake patients with elevated intracranial pressure from hydrocephalus or trauma.

Anatomical restrictions in the transsphenoidal, transclival approach to the upper clival region: a cadaveric, anatomic study.

OBJECTIVE: Tumours in the clival region are difficult to remove surgically. Before the 1970s, clival tumours had very high mortality and morbidity rates. METHODS: An anatomic dissection was performed on 24 spheno-occipital bone blocks obtained from 28 adult cadavers. The internal carotid artery, paraclival carotid tubercle, sixth cranial nerve and dorsum sellae in the upper clival region were analyzed qualitatively and quantitatively. For the histological evaluation, 4 samples were decalcified and sagittal sections were cut. From the eight blocks obtained, 32 incisions were made in the axial plane, and the tissue was analyzed. RESULTS: Using microscopy, a clival recess was clearly identified in 15 of the 24 (62.5%) samples. Paraclival carotid tubercles were observed in 19 (79.16%) of the samples. In the upper clival and petroclival region, the sixth cranial nerve had directional changes at the dural porus, the petrous apex and the lateral wall of the cavernous segment of the internal carotid artery. At the dorsum sellae level, the distance between the medial surfaces of both internal carotid arteries was a mean of 15.33 ± 2.12 mm. This distance at the pharyngeal tubercle was a mean of 38.95 ± 4.67 mm. On all the histological sections, the distance of the sixth cranial nerve from the dural porus to the cavernous sinus was within the basilar plexus, along with the subarachnoid membranes around it. On the petrous apex level, the sixth cranial nerve was fixed to the petrous apex and the internal carotid artery with connective tissue formed by dense collagen fibres. The sixth cranial nerve and the internal carotid artery are tightly surrounded by dense collagen connective tissue, and the relative proximity between the carotids on the dorsum sellae level can be easily damaged during the transsphenoidal-transclival approach. Similarly, due to the ligamentous fixation on the dural porus and the petrous apex surfaces, there is a high risk of injury to the carotid artery and sixth cranial nerve. CONCLUSION: This study determines the relationship between the sixth cranial nerve and the internal carotid artery at the upper clivus and to provide morphologic details that is essential for the risks of transclival surgery.

Clivus chordoma: is it enough to image the primary site?

Chordomas are rare malignant tumors arising from embryonic remnants of the primitive notochord, around which the skull base and vertebral column develop. They are locally aggressive but metastasize rarely. To our knowledge, this is the first reported case of synchronous intraosseous chordomas. A 32-year-old man presented with intermittent double vision secondary to a right-side abducent nerve palsy. Imaging revealed a clivus chordoma and an asymptomatic synchronous second primary chordoma in the fifth lumbar vertebra. Both chordomas were surgically excised: the clivus using the endonasal, endoscopic route and the L5 vertebra by total vertebral excision and replacement with a titanium prosthesis. The patient made an uneventful and complete recovery. We have modified our departmental practice as we believe that all patients diagnosed with chordoma should have magnetic resonance imaging of their entire spinal tract to exclude a second primary chordoma.