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Brain Tumor Research and Treatment Apr 2024Giant cell tumors (GCTs) are locally aggressive primary bone tumors of osteoclast-like cells. Most GCTs occur within the long bones, and primary GCTs involving the...
Giant cell tumors (GCTs) are locally aggressive primary bone tumors of osteoclast-like cells. Most GCTs occur within the long bones, and primary GCTs involving the clivus are extremely rare. We present the case of an 18-year-old boy with binocular horizontal diplopia with an insidious onset who was found to have a hypointense enhancing mass involving the clivus and left side dorsum sellae on magnetic resonance images. The tumor was completely resected via an endoscopic endonasal transclival approach, and histopathologic examination via immunohistochemistry indicated a GCT. The patient's left abducens nerve palsy improved slightly after surgery. Because of the rarity of GCTs, there is no consensus about the definitive treatment protocol. However, we suggest that gross total resection is the treatment of choice, and denosumab plays a critical role in patients with subtotal resection.
PubMed: 38742263
DOI: 10.14791/btrt.2024.0010 -
Endoscopic transsphenoidal resection of parasellar abducens nerve schwannoma: A video demonstration.Surgical Neurology International 2024The abducens nerve schwannoma (ANS) in the sellar and parasellar region are extremely rare. Only around two dozen of ANS have been described in the world literature....
BACKGROUND
The abducens nerve schwannoma (ANS) in the sellar and parasellar region are extremely rare. Only around two dozen of ANS have been described in the world literature. These cases were, however, operated through the transcranial approach. We demonstrate, with the help of an edited video, that ANS located in the sellar and parasellar region can be safely and effectively operated through a transsphenoidal approach under endoscopic visualization.
CASE DESCRIPTION
Here, we present a case of a 30-year-old male who presented with a nine-month history of diplopia, weight gain, and loss of sexual functions. On neuro-opthalmological examination, a mild abducens palsy on the left side. Other cranial nerves were intact. On endocrinological testing, mild hypopituitarism on gonadal and thyroid axes. Magnetic resonance imaging (MRI) scan showed a contrast-enhanced cystic lesion in the sellar and parasellar region extending into the left temporal fossa. The patient underwent endonasal transsphenoidal endoscopic resection. A binostril standard approach was used, the left middle concha resected, and the nasoseptal flap was raised [Video 1]. The tumor was relatively soft and avascular yet invasive and could be removed with straight and curved suctions and gentle curettage. Subcapsular dissection was the key to saving the sixth nerve. Only minimal remnant posterior to the left internal carotid artery was assumed to be left behind. No cerebrospinal fluid (CSF) leakage was noted during the surgery. The skull base defect was reconstructed with the left-sided nasoseptal flap [Video 1]. Postoperatively, no new cranial nerve deficits. Diplopia is preoperative. Endocrine functions were unchanged. No CSF leak was observed. Postoperative MRI scan showed a near total resection. There was no operation-relevant complication. Diplopia resolved completely in a follow-up period of 6 months.
CONCLUSION
The endoscopic transsphenoidal route is safe and effective for the resection of parasellar ANS. Subcapsular dissection is key to keep the sixth nerve intact.
PubMed: 38741979
DOI: 10.25259/SNI_609_2023 -
Frontiers in Neuroanatomy 2024The topographic anatomy of the abducens nerve has been the subject of research for more than 150 years. Although its vulnerability was initially attributed to its...
The topographic anatomy of the abducens nerve has been the subject of research for more than 150 years. Although its vulnerability was initially attributed to its length, this hypothesis has largely lost prominence. Instead, attention has shifted toward its intricate anatomical relations along the cranial base. Contrary to the extensive anatomical and neurosurgical literature on abducens nerve anatomy in humans, its complex anatomy in other species has received less emphasis. The main question addressed here is why the human abducens nerve is predisposed to injury. Specifically, we aim to perform a comparative analysis of the basicranial pathway of the abducens nerve in mammals and primates. Our hypothesis links its vulnerability to cranial base flexion, particularly around the sphenooccipital synchondrosis. We examined the abducens nerve pathway in various mammals, including primates, humans ( = 40; 60% males; 40% females), and human fetuses ( = 5; 60% males; 40% females). The findings are presented at both the macroscopic and histological levels. To associate our findings with basicranial flexion, we measured the cranial base angles in the species included in this study and compared them to data in the available literature. Our findings show that the primitive state of the abducens nerve pathway follows a nearly flat (unflexed) cranial base from the pontomedullary sulcus to the superior orbital fissure. Only the gulfar segment, where the nerve passes through Dorello's canal, demonstrates some degree of variation. We present evidence indicating that the derived state of the abducens pathway, which is most pronounced in humans from an early stage of development, is characterized by following the significantly more flexed basicranium. Overall, the present study elucidates the evolutionary basis for the vulnerability of the abducens nerve, especially within its gulfar and cavernous segments, which are situated at the main synchondroses between the anterior, middle, and posterior cranial fossae-a unique anatomical relation exclusive to the abducens nerve. The principal differences between the pathways of this nerve and those of other cranial nerves are discussed. The findings suggest that the highly flexed human cranial base plays a pivotal role in the intricate anatomical relations and resulting vulnerability of the abducens nerve.
PubMed: 38741761
DOI: 10.3389/fnana.2024.1383126 -
Diagnostics (Basel, Switzerland) Apr 2024A 77-year-old-man with arterial hypertension, diabetes mellitus type II presented at our clinic for a routine ophthalmological exam. He complained of intermittent double...
A 77-year-old-man with arterial hypertension, diabetes mellitus type II presented at our clinic for a routine ophthalmological exam. He complained of intermittent double vision. The ophthalmic examination revealed paralysis of III (n. oculomotorius) and VI (n. abducens) cranial nerves with ptosis, deficit in elevation and abduction of the left eye. The patient underwent urgent MRI imaging of the brain/orbits and paranasal sinuses, and urgent neurological assessment. MRI revealed a volume-occupying process, starting from the posterior wall of the left maxillary sinus with perineural diffusion and involvement of the homolateral trigeminal nerve, intracranial spread in the medial cranial fossa and involvement of the cavernous, sphenoidal sinuses and the orbital apex on the left side. Biopsy was performed, and the histology resulted in sinonasal squamous cell carcinoma with intracranial spread.
PubMed: 38732347
DOI: 10.3390/diagnostics14090932 -
Journal of Neurosurgery. Case Lessons May 2024Unilateral cranial nerve (CN) VI, or abducens nerve, palsy is rare in children and has not been reported in association with Chiari malformation type 1 (CM1) in the...
BACKGROUND
Unilateral cranial nerve (CN) VI, or abducens nerve, palsy is rare in children and has not been reported in association with Chiari malformation type 1 (CM1) in the absence of other classic CM1 symptoms.
OBSERVATIONS
A 3-year-old male presented with acute incomitant esotropia consistent with a unilateral, left CN VI palsy and no additional neurological symptoms. Imaging demonstrated CM1 without hydrocephalus or papilledema, as well as an anterior inferior cerebellar artery (AICA) vessel loop in the immediate vicinity of the left abducens nerve. Given the high risk of a skull base approach for direct microvascular decompression of the abducens nerve and the absence of other classic Chiari symptoms, the patient was initially observed. However, as his palsy progressed, he underwent posterior fossa decompression with duraplasty (PFDD), with the aim of restoring global cerebrospinal fluid dynamics and decreasing possible AICA compression of the left abducens nerve. Postoperatively, his symptoms completely resolved.
LESSONS
In this first reported case of CM1 presenting as a unilateral abducens palsy in a young child, possibly caused by neurovascular compression, the patient's symptoms resolved after indirect surgical decompression via PFDD.
PubMed: 38710112
DOI: 10.3171/CASE23539 -
Cureus Apr 2024Herpes zoster ophthalmicus (HZO) is a condition resulting from the reactivation of dormant varicella zoster virus within the sensory nerve ganglion in the ophthalmic...
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.
PubMed: 38707108
DOI: 10.7759/cureus.57506 -
Cureus Apr 2024Myasthenia gravis is an autoimmune disease of the neuromuscular junction caused by autoantibodies directed against the acetylcholine receptors. It presents with...
Myasthenia gravis is an autoimmune disease of the neuromuscular junction caused by autoantibodies directed against the acetylcholine receptors. It presents with skeletal muscle weakness, often initially presenting with ocular symptoms such as ptosis and diplopia. When myasthenia gravis is isolated to only ocular symptoms, it is referred to as ocular myasthenia gravis (OMG). Here, we present an atypical initial presentation of OMG in a 68-year-old male patient presenting with isolated abducens nerve palsy at the initial onset. With this case report, we highlight the importance of a thorough history and clinical assessment necessary for a timely diagnosis of OMG in patients who present with isolated abducens nerve palsy.
PubMed: 38707069
DOI: 10.7759/cureus.57501 -
Brain & Spine 2024Hydrocephalus, altering cerebrospinal fluid (CSF) dynamics, affects 175 per 100,000 adults worldwide. Ventriculoperitoneal shunts (VPS) manage symptomatic hydrocephalus,...
INTRODUCTION
Hydrocephalus, altering cerebrospinal fluid (CSF) dynamics, affects 175 per 100,000 adults worldwide. Ventriculoperitoneal shunts (VPS) manage symptomatic hydrocephalus, with 125,000 cases annually. Despite efficacy, VPS face complications, necessitating interventions.
RESEARCH QUESTION
"What are the mechanisms and risk factors for bilateral VIth and VIIth lower motor neuron palsies in hydrocephalus patients with a fourth ventriculoperitoneal shunt?"
MATERIAL AND METHODS
This study details a 36-year-old female with a neonatal meningitis history, multiple shunt replacements, admitted for abdominal pain secondary to pelvic inflammatory disease. An abdominal shunt catheter removal and external ventricular drain placement occurred after consultation with a general surgeon. A cardiac atrial approach and subsequent laparoscopic abdominal approach were performed without complications.
RESULTS
After one month, the patient showed neurological complications, including decreased facial expression, gait instability, and bilateral VIth and VIIth lower motor neuron palsies, specifically upgazed and convergence restriction.
DISCUSSION
The complication's pathophysiology is discussed, attributing it to potential brainstem herniation from over-drainage of CSF. Literature suggests flexible endoscopic treatments like aqueductoplasty/transaqueductal approaches into the fourth ventricle.
CONCLUSIONS
This study underscores the need for increased awareness in monitoring neurological outcomes after the fourth ventriculoperitoneal shunt, particularly in cases with laparoscopic-assisted abdominal catheter placement. The rarity of bilateral abducens and facial nerve palsies emphasizes the importance of ongoing research to understand pathophysiology and develop preventive and therapeutic strategies for this unique complication.
PubMed: 38706799
DOI: 10.1016/j.bas.2024.102824 -
The Journal of Craniofacial Surgery May 2024In recent years, endoscopy has become an increasingly common tool used during neurosurgical procedures. However, its application in treating cerebellopontine angle (CPA)...
In recent years, endoscopy has become an increasingly common tool used during neurosurgical procedures. However, its application in treating cerebellopontine angle (CPA) lesions has not progressed as rapidly. In this study, the authors present their initial experience with surgically treating CPA lesions using a fully endoscopic keyhole retrosigmoid approach. They conducted a retrospective analysis of clinical data from patients who underwent endoscopic keyhole CPA surgery at their center between May 2017 and April 2022. They provide a comprehensive explanation of this method and an overview of the strategies that have been developed to achieve better clinical outcomes. The study included 107 patients, consisting of 10 cases of vestibular schwannoma, 21 cases of epidermoid cyst, 32 cases of trigeminal neuralgia, and 44 cases of hemifacial spasm. The authors analyzed the clinicodemographic details of the patients. Among the 31 tumor cases, gross total resection was achieved in 25 patients (80.6%), while near-total resection was performed in 6 patients (19.4%). In patients with trigeminal neuralgia, facial pain resolved in 31 out of 32 patients (96.9%). Similarly, facial convulsions disappeared or were relieved in all 44 patients (100%) with hemifacial spasms after the operation. Postoperative complications included facial nerve paresis (n=9, 8.4%), with improvement observed in 6 cases during follow-up, transient facial hypoesthesia (n=3, 2.8%), cerebrospinal fluid rhinorrhea (n=3, 2.8%), transient abducens paresis (n=1, 0.9%), and postoperative hemorrhage (n=1, 0.9%). Endoscopy provides improved deep illumination and, combined with close-up observation, enhances the visualization of structures within the CPA region. The fully endoscopic keyhole technique is a safe and effective method for managing CPA lesions.
PubMed: 38688021
DOI: 10.1097/SCS.0000000000010141 -
Operative Neurosurgery (Hagerstown, Md.) Apr 2024Basal encephaloceles are the result of a concomitant cranial and dural defect that allows for inferior displacement of cerebral tissue, meninges, and cerebrospinal fluid...
BACKGROUND AND IMPORTANCE
Basal encephaloceles are the result of a concomitant cranial and dural defect that allows for inferior displacement of cerebral tissue, meninges, and cerebrospinal fluid into the paranasal sinuses and outside the cranial vault. This work illustrates a step-by-step surgical approach of a successful single-stage, endoscopic repair of a congenital basal encephalocele in a 10-year-old child, using a free mucosal middle turbinate graft that provided effective results without utilization of traditional open reconstructive techniques or vascularized flaps.
CLINICAL PRESENTATION
A previously healthy 10-year-old male with a history of unilateral clear rhinorrhea was admitted as an inpatient because of an acute episode of nausea, vomiting, and confusion, accompanied by fever, diplopia, and bilateral abducens nerve palsies. Preoperative imaging revealed a 2-cm right-sided intranasal mass accompanied by a subcentimeter skull base defect spanning the lateral lamella. After completing a course of intravenous antibiotic therapy for 1 week after a negative lumbar puncture to ensure clearance of intracranial infection, the decision was made to proceed with definitive endoscopic skull base repair to obviate recurrent bacterial meningitis episodes and potential neurological complications.
CONCLUSION
This study demonstrates technical feasibility of a single-stage endoscopic endonasal approach for pediatric basal encephalocele resection and repair which minimizes craniofacial morbidity associated with traditional open approaches and sinonasal morbidity associated with local pedicle-based flaps for small cranial base defects in this unique patient population.
PubMed: 38687037
DOI: 10.1227/ons.0000000000001194