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Journal of Neurovirology Dec 2020Since COVID-19 was first reported, different neurological complications have been acknowledged, but their description is constantly evolving. We report a case of...
Since COVID-19 was first reported, different neurological complications have been acknowledged, but their description is constantly evolving. We report a case of concurrent tonic pupil and trochlear nerve palsy in this context. A 62-year-old man reported a 5-day history of binocular vertical diplopia and blurred vision in his left eye, noticing that his left pupil was dilated. He had suffered a flu-like syndrome 2 weeks before. Clinical exam showed a right trochlear nerve palsy and a left mydriatic pupil. MRI, X chest ray, and analytical results were normal. Antibodies for SARS-CoV-2 were positive (low IgM and high IgG titers). Antiganglioside antibodies were negative. A 0.125% pilocarpine test confirmed Adie's pupil diagnosis. The patient was treated with a tapered prednisone dose with resolution of his diplopia but no change in Adie's pupil. This is the first case reporting Adie's pupil as a postinfectious manifestation of COVID-19. An immune-mediated mechanism is presumed.
Topics: Anti-Inflammatory Agents; COVID-19; Diplopia; Humans; Male; Middle Aged; Prednisone; SARS-CoV-2; Tonic Pupil; Trochlear Nerve Diseases
PubMed: 32910433
DOI: 10.1007/s13365-020-00909-1 -
Journal of Clinical Imaging Science 2020The medial longitudinal fasciculus (MLF) is a paired, highly specialized, and heavily myelinated nerve bundle responsible for extraocular muscle movements, including the... (Review)
Review
The medial longitudinal fasciculus (MLF) is a paired, highly specialized, and heavily myelinated nerve bundle responsible for extraocular muscle movements, including the oculomotor reflex, saccadic eye movements an smooth pursuit, and the vestibular ocular reflex. Clinically, lesions of the MLF are classically associated with internuclear ophthalmoplegia. However, clinical manifestations of a lesion in the MLF may be more complex and variable. We provide an overview of the neuroanatomy, neurologic manifestations, and correlative examples of the imaging findings on brain MRI of MLF lesions to provide the clinician and radiologist with a more comprehensive understanding of the MLF and potential clinical manifestations for an MLF lesion.
PubMed: 33408958
DOI: 10.25259/JCIS_49_2020 -
Anatomical Record (Hoboken, N.J. : 2007) Apr 2019The surgical procedures directed to the orbit are invariably reported to be one of the most challenging procedures of the neurosurgery and it is very important to take... (Review)
Review
The surgical procedures directed to the orbit are invariably reported to be one of the most challenging procedures of the neurosurgery and it is very important to take measures to protect the ocular nerves. Many researchers have tried to identify safe approaches or safe regions in the orbit but the suggestions and results vary among published studies. The ocular motor nerves are under risk of injury during various approaches to the orbit. Simple but careful attention to potential variations in the origin and anatomical course of the ocular nerves and their relationships to the orbit may help to define "safe zones" during various approaches, thus, help to enhance clinical outcomes. The objective of this review, therefore, is to discuss the surgical anatomy of the orbit with special emphasis on oculomotor, trochlear, and abducens nerves and further emphasize their relationships with a surgical point of view during various approaches directed to the orbit. Anat Rec, 302:568-574, 2019. © 2018 Wiley Periodicals, Inc.
Topics: Cranial Nerves; Humans; Microsurgery; Oculomotor Muscles; Orbit
PubMed: 29659177
DOI: 10.1002/ar.23820 -
AJNR. American Journal of Neuroradiology May 2017The trochlear groove and trochlear cistern are anatomic landmarks closely associated with the tentorial segment of cranial nerve IV. The purposes of this study were to...
BACKGROUND AND PURPOSE
The trochlear groove and trochlear cistern are anatomic landmarks closely associated with the tentorial segment of cranial nerve IV. The purposes of this study were to describe the MR imaging appearances of the trochlear groove and trochlear cistern and to test our hypothesis that knowledge of these anatomic landmarks facilitates identification of cranial nerve IV in routine clinical practice.
MATERIALS AND METHODS
For this retrospective study, consecutive MR imaging examinations of the sinuses performed in 25 patients (50 sides) at our institution were reviewed. Patient characteristics and study indications were recorded. Three readers performed independent assessments of trochlear groove, cistern, and nerve visibility on coronal images obtained by using a T2-weighted driven equilibrium radiofrequency reset pulse sequence.
RESULTS
Interobserver agreement was 78% for visibility of the trochlear groove, 56% for the trochlear cistern, and 68% for cranial nerve IV. Following consensus review, the trochlear groove was present in 44/50 sides (88%), the trochlear cistern was present in 25/50 sides (50%), and cranial nerve IV was identified in 36/50 sides (72%). When the trochlear groove was present, cranial nerve IV was identified in 35/44 sides (80%), in contrast to 1/6 sides (17%) with no groove ( = .0013). When the trochlear cistern was present, cranial nerve IV was identified in 23/25 sides (92%), in contrast to 13/25 sides (52%) with no cistern ( = .0016).
CONCLUSIONS
The trochlear groove and trochlear cistern are anatomic landmarks that facilitate identification of cranial nerve IV in routine clinical practice.
Topics: Adult; Anatomic Landmarks; Female; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Retrospective Studies; Trochlear Nerve
PubMed: 28302606
DOI: 10.3174/ajnr.A5117 -
Journal of Neurology Apr 2022Ocular motor nerve palsies (OMNP) frequently cause patients to present in an emergency room. In the following study, we report the differential diagnosis of OMNP by use...
BACKGROUND
Ocular motor nerve palsies (OMNP) frequently cause patients to present in an emergency room. In the following study, we report the differential diagnosis of OMNP by use of magnetic resonance imaging (MRI) and CSF examination as a standard.
METHOD
We performed a data analysis of N = 502 patients who presented with oculomotor, trochlear, and/or abducens nerve palsy in the emergency room of the Department of Neurology, University of Ulm, between January 2006 and December 2019. We report clinical and MRI scan findings in all patients; furthermore, the CSF of 398 patients has been analysed.
RESULTS
Abducens nerve palsies were most common (45%), followed by palsies of the oculomotor (31%) (CNP III) and trochlear nerve (15%). Multiple OMNPs were seen in 9% of our cohort. The most common causes included inflammations (32.7%), space-occupying lesions, such as aneurysms or neoplasms (17.3%), diabetes mellitus (13.3%), and brainstem infarctions (11%). Still 23.4% of the patients could not be assigned to any specific cause after differential diagnostic procedures and were described as idiopathic. One of three patients with an inflammation and 39% of the patients with space-occupying lesions showed additional cranial nerve deficits.
CONCLUSION
Inflammation and space-occupying processes were the most frequent causes of OMNP, although brainstem infarctions also play a significant role, in particular in CNP III. The presence of additional CNPs increases the probability of an inflammatory or space-occupying cause.
Topics: Abducens Nerve Diseases; Cranial Nerve Diseases; Diagnosis, Differential; Humans; Oculomotor Nerve Diseases; Paralysis; Trochlear Nerve; Trochlear Nerve Diseases
PubMed: 34537871
DOI: 10.1007/s00415-021-10761-w -
Journal of Orthopaedic Surgery and... May 2022Patellar dislocation can cause a series of changes in the trochlear groove and patella. However, the influence of patellar dislocation on the medialis (VM) and vastus...
Electrophysiological and pathological changes in the vastus medialis and vastus lateralis muscles after early patellar reduction and nerve growth factor injection in rabbits with patellar dislocation.
BACKGROUND
Patellar dislocation can cause a series of changes in the trochlear groove and patella. However, the influence of patellar dislocation on the medialis (VM) and vastus lateralis (VL) muscles and whether nerve growth factor (NGF) is beneficial to proprioceptive rehabilitation for patellar dislocation are unknown. The purpose of this study was to investigate the effects on VM and VL after the injection of NGF and early reduction in rabbits for patellar dislocation with electrophysiological and pathological analysis.
METHODS
Sixty 2-month-old rabbits were randomly divided into four groups (15 rabbits in each group). Rabbits in Group 1, Group 2, and Group 3 underwent patellar dislocation surgery, and rabbits in Group 4 underwent sham surgery. One month later, patellar reduction was performed in Groups 1 and 2. NGF was injected into the rabbits of Group 1. The electrophysiological and pathological changes in VM and VL were analyzed at 1 month and 3 months after patellar reduction.
RESULTS
The electrophysiological and pathological indices in Groups 1 and 2 were significantly different from those in Group 3 at 1 and 3 months after patellar reduction. There were significant differences between NGF injection Group 1 and Group 2 without NGF injection. There was no significant difference between Group 1 and Group 4 at 3 months after patellar reduction.
CONCLUSIONS
Patellar dislocation can cause abnormal electrophysiological and pathological effects on VM and VL. Patellar reduction should be performed as early as possible, and NGF injection may be beneficial to the rehabilitation of proprioception.
Topics: Animals; Rabbits; Nerve Growth Factor; Patella; Patellar Dislocation; Proprioception; Quadriceps Muscle
PubMed: 35570303
DOI: 10.1186/s13018-022-03170-w -
Neurologia Medico-chirurgica Oct 2021Schwannomas of the trochlear nerve are relatively rare, and most patients present with preoperative diplopia because of trochlear nerve palsy. We describe the case of a...
Schwannomas of the trochlear nerve are relatively rare, and most patients present with preoperative diplopia because of trochlear nerve palsy. We describe the case of a 61-year-old male patient with a trochlear nerve schwannoma and no pre- and postoperative diplopia, despite his trochlear nerve being cut during the operation. We aimed to investigate the frequency of postoperative diplopia associated with intraoperative trochlear nerve disturbance by reviewing previous case reports, wherein postoperative diplopia did not occur after the trochlear nerve was cut intraoperatively. We recorded the frequency of diplopia because of intraoperative trochlear nerve disturbance, such as the trochlear nerve being cut, in cases without pre- and postoperative diplopia. We searched the PubMed, Medline, and Google Scholar databases for works published from 1976 to 2020 and followed the preferred reporting items for systematic reviews and meta-analyses guidelines. We reviewed 36 publications and found 92 cases of trochlear nerve schwannoma. Surgical resection was performed for 43 patients, of whom 40 were kept under observation and 9 were treated with radiation therapy. Of the 43 cases, 9 without preoperative diplopia underwent gross total resection. We analyzed ten cases (including ours) without preoperative diplopia to check for postoperative diplopia. In total, four cases, including ours, did not display postoperative diplopia despite the trochlear nerve being cut. This may be attributed to the preoperatively acquired motor and sensory fusion in the patient's vision because of tumor progression. Our findings may benefit neurosurgeons who treat patients with schwannomas and help them predict patients' outcomes.
Topics: Humans; Male; Middle Aged; Cranial Nerve Neoplasms; Diplopia; Neurilemmoma; Trochlear Nerve; Trochlear Nerve Diseases
PubMed: 34321383
DOI: 10.2176/nmc.oa.2021-0079 -
Neural Regeneration Research Oct 2018Objective and accurate assessment of the degree of ocular motor nerve palsy is helpful not only in the evaluation of prognosis, but also for the screening of treatment...
Objective and accurate assessment of the degree of ocular motor nerve palsy is helpful not only in the evaluation of prognosis, but also for the screening of treatment methods. However, there is currently no comprehensive measure of its severity. In this study, we designed the Ocular Motor Nerve Palsy Scale and investigated its validity and reliability. Six experts were invited to grade and evaluate the scale. The study recruited 106 patients with a definite diagnosis of unilateral isolated ocular motor nerve palsy. Three physicians evaluated the patients using the scale. One of the three physicians evaluated the patients again after 24 hours. The content validity index (CVI) and factor analysis were used to analyze the scale's construct validity. The intraclass correlation coefficient and Cronbach's alpha were used to evaluate the inter-rater and test-retest reliability and the internal consistency. The CVI results (I-CVI = 1.0, S-CVI = 0.9, P = 0.016, K = 1) indicated good content validity. Factor analysis extracted two common factors that accounted for 85.2% of the variance. Furthermore, the load value of each component was above 0.8, indicating good construct validity. The Ocular Motor Nerve Palsy Scale was found to be highly reliable, with an inter-rater reliability intraclass correlation coefficient of 0.965 (P < 0.01), a test-retest reliability intraclass correlation coefficient of 0.976 (P < 0.01), and Cronbach's alpha values of 0.63-0.70. In conclusion, the Ocular Motor Nerve Palsy Scale with good validity and reliability can be used to quantify the severity of ocular motor nerve palsy. This study was registered at Chinese Clinical Trial Registry (registration number: ChiCTR-OOC-17010702).
PubMed: 30136702
DOI: 10.4103/1673-5374.238716 -
Clinical Orthopaedics and Related... Nov 2015The median and radial nerves are at risk of iatrogenic injury when performing arthroscopic arthrolysis with anterior capsulectomy. Although prior anatomic studies have...
BACKGROUND
The median and radial nerves are at risk of iatrogenic injury when performing arthroscopic arthrolysis with anterior capsulectomy. Although prior anatomic studies have identified the position of these nerves, little is known about how elbow positioning and joint insufflation might influence nerve locations.
QUESTIONS/PURPOSES
In a cadaver model, we sought to determine whether (1) the locations of the median and radial nerves change with variation of elbow positioning; and whether (2) flexion and joint insufflation increase the distance of the median and radial nerves to osseous landmarks after correcting for differences in size of the cadaveric specimens.
METHODS
The median and radial nerves were marked with a radiopaque thread in 11 fresh-frozen elbow specimens. Three-dimensional radiographic scans were performed in extension, in 90° flexion, and after joint insufflations in neutral rotation, pronation, and supination. Trochlear and capitellar widths were analyzed. The distances of the median nerve to the medial and anterior edge of the trochlea and to the coronoid were measured. The distances of the radial nerve to the lateral and anterior edge of the capitulum and to the anterior edge of the radial head were measured. We analyzed the mediolateral nerve locations as a percentage function of the trochlear and capitellar widths to control for differences regarding the size of the specimens.
RESULTS
The mean distance of the radial nerve to the lateral edge of the capitulum as a percentage function of the capitellar width increased from 68% ± 17% in extension to 91% ± 23% in flexion (mean difference = 23%; 95% confidence interval [CI], 5%-41%; p = 0.01). With the numbers available, no such difference was observed regarding the location of the median nerve in relation to the medial border of the trochlea (mean difference = 5%; 95% CI, -13% to 22%; p = 0.309). Flexion and joint insufflation increased the distance of the nerves to osseous landmarks. The mean distance of the median nerve to the coronoid tip was 5.4 ± 1.3 mm in extension, 9.1 ± 2.3 mm in flexion (mean difference = 3.7 mm; 95% CI, 2.04-5.36 mm; p < 0.001), and 12.6 ± 3.6 mm in flexion and insufflation (mean difference = 3.5 mm; 95% CI, 0.81-6.19 mm; p = 0.008). The mean distance of the radial nerve to the anterior edge of the radial head increased from 4.7 ± 1.8 mm in extension to 7.7 ± 2.7 mm in flexion (mean difference = 3.0 mm; 95% CI, 0.96-5.04 mm; p = 0.005) and to 11.9 ± 3.0 mm in flexion with additional joint insufflation (mean difference = 4.2 mm; 95% CI, 1.66-6.74 mm; p = 0.002).
CONCLUSIONS
The radial nerve shifts medially during flexion from the lateral to the medial border of the inner third of the capitulum. The median nerve is located at the medial quarter of the joint. The distance of the median and radial nerves to osseous landmarks doubles from extension to 90° flexion and triples after joint insufflation.
CLINICAL RELEVANCE
Elbow arthroscopy with anterior capsulectomy should be performed cautiously at the medial aspect of the joint to avoid median nerve lesions. Performing arthroscopic anterior capsulectomy in flexion at the lateral aspect of the joint and in slight extension at the medial edge of the capitulum could enhance safety of this procedure.
Topics: Aged; Aged, 80 and over; Anatomic Landmarks; Arthroscopy; Biomechanical Phenomena; Cadaver; Elbow Joint; Female; Humans; Insufflation; Male; Median Nerve; Patient Positioning; Peripheral Nerve Injuries; Radial Nerve; Radiography; Range of Motion, Articular
PubMed: 26152782
DOI: 10.1007/s11999-015-4442-3 -
Investigative Ophthalmology & Visual... Apr 2017To spatially and temporally define ocular motor nerve development in the presence and absence of extraocular muscles (EOMs).
PURPOSE
To spatially and temporally define ocular motor nerve development in the presence and absence of extraocular muscles (EOMs).
METHODS
Myf5cre mice, which in the homozygous state lack EOMs, were crossed to an IslMN:GFP reporter line to fluorescently label motor neuron cell bodies and axons. Embryonic day (E) 11.5 to E15.5 wild-type and Myf5cre/cre:IslMN:GFP whole mount embryos and dissected orbits were imaged by confocal microscopy to visualize the developing oculomotor, trochlear, and abducens nerves in the presence and absence of EOMs. E11.5 and E18.5 brainstems were serially sectioned and stained for Islet1 to determine the fate of ocular motor neurons.
RESULTS
At E11.5, all three ocular motor nerves in mutant embryos approached the orbit with a trajectory similar to that of wild-type. Subsequently, while wild-type nerves send terminal branches that contact target EOMs in a stereotypical pattern, the Myf5cre/cre ocular motor nerves failed to form terminal branches, regressed, and by E18.5 two-thirds of their corresponding motor neurons died. Comparisons between mutant and wild-type embryos revealed novel aspects of trochlear and oculomotor nerve development.
CONCLUSIONS
We delineated mouse ocular motor nerve spatial and temporal development in unprecedented detail. Moreover, we found that EOMs are not necessary for initial outgrowth and guidance of ocular motor axons from the brainstem to the orbit but are required for their terminal branching and survival. These data suggest that intermediate targets in the mesenchyme provide cues necessary for appropriate targeting of ocular motor axons to the orbit, while EOM cues are responsible for terminal branching and motor neuron survival.
Topics: Animals; Axons; Eye Movements; Mice; Microscopy, Confocal; Models, Animal; Motor Neurons; Oculomotor Muscles; Oculomotor Nerve
PubMed: 28437527
DOI: 10.1167/iovs.16-21268