Central Caudal Nucleus Research Articles

Case report of pediatric tuberculoma with occulomotor and trochlear nerve palsy

Introduction: Peculiar case of a tuberculoma in the midbrain, leading to superior oblique and inferior rectus palsy along with a moderate degree of ptosis of the right eye. Presenting features: 5 year-old female patient with complaints of fever, drooping of the right upper eyelid and uprolling of the right eye. 15 degree Hypertropia of the right eye with head tilt on the left side. The pupils showed sluggish reaction. Total restriction of ocular movements in the downward gaze suggesting the under action of the superior oblique and inferior rectus muscle. Moderate degree of unilateral ptosis. Vertical diplopia in downward gaze. Investigations: Cranial MRI with Intravenous contrast revealed a well-defined enhancing lesion measuring about 10 × 8 mm with small non-enhancing area noted within with significant edema in the midbrain. Presence of a tuberculoma in midbrain involving the trochlear nerve nucleus, the dorsolateral and central nucleus of the occulomotor nerve. Discussion: Partial fascicular oculomotor palsy leading to isolated inferior rectus palsy caused by midbrain infarction suggesting the possible selective involvement of an individual fascicle. Compression of the central caudal nucleus of the occulomotor nerve by the edema present around the tuberculoma gives rise to moderate ptosis in the patient. Patient received anti tubercular treatment. The improvement of the ocular symptoms after one month of anti-tubercular treatment confirmed the finding of a tuberculoma.

Isolated nuclear III nerve paresis secondary to neurocysticercosis showing spontaneous clinical improvement.

Sir, We wish to present a case of isolated nuclear IIIrd nerve paresis secondary to neurocysticercosis (NCC) showing spontaneous clinical improvement. Isolated third cranial nerve palsy is rare in NCC. A 14-year-old male child of Nepali origin presented with diplopia for 6 days in left lateral gaze and drooping of his upper eyelids in both eyes. The complaints were insidious in onset, non-progressive simultaneous in both eyes with no diurnal fluctuation. Rest of his present and past medical history was not significant. He had history of pork consumption. His general physical examination and systemic examination including neurological examination was unremarkable. His visual acuity was 6/6 OU with increased wrinkling on forehead. He had severe neurological ptosis in both eyes with poor levator palpebrae superioris (LPS) action with no Marcus Gunn phenomenon and no sign s/o fatigueability. He also had an exotropia of about 15 degree and mild paresis of elevation of eyeball in right eye maximum in lateral gaze. He had mild paresis of his right medial rectus with end gaze nystagmus in left gaze. Rest of the ophthalmological examination was unremarkable including papillary reactions. Diplopia charting showed horizontal diplopia in all gaze positions with maximum difference in left lateral gaze positions [Figure 1]. While waiting for his investigation reports his sign and symptoms showed spontaneous clinical improvement. His magnetic resonance imaging (MRI) showed a solitary ring-enhancing lesion in the pre-aqueductal region of mid brain of size 0.72 × 0.68 cm involving IIIrd nerve nucleus with peri lesional edema [Figure 2]. His lumbar puncture was done and it revealed CSF protein levels 60 and it also showed 9 white blood cells mainly lymphocytes. ADA levels in his CSF were within normal limit. His serology revealed positive IgG levels for taenia solium (1.13 U/ml) by ELISA. In the light of the above findings the patient was diagnosed as a case of nuclear third nerve paresis secondary to NCC of brainstem. After consultation with Department of Neurology the patient was put on oral albendazole and prednisolone. He was continuously followed up with no similar episodes till 1 year after. Figure 1 (a) Ptosis in both eyes. (b) Paresis of Medial rectus in right eye. (c) Paresis of elevation in right eye. (d-f) Respective improvement Figure 2 Transverse section in MRI showing solitary ring enhancing lesion in the pre-aqueductal region of mid brain of size 0.72 × 0.68 cm involving IIIrd nerve nucleus with peri lesional edema NCC is the most common parasitic infestation of the nervous system.[1] Globally, NCC is endemic in Central and South America, sub-Saharan Africa, and in some regions of the Far East, including the Indian subcontinent, Indonesia, and China, reaching an incidence of 3.6% in some regions.[1] Del Brutto et al. have suggested diagnostic criteria for NCC.[2] In our case these criteria were fulfilled for probable diagnosis of NCC. It usually presents with seizures. Other various CNS clinical manifestations include headache, hydrocephalus, chronic meningitis, focal neurological deficits, dementia and psychiatric manifestations.[3] Involvement of third nerve is rare especially due to a parenchymal lesion.[4] Fluctuation in perilesional edema was probably responsible for spontaneous clinical recovery in our patient. The lesion in such nuclear third nerve paresis involves the central caudal nucleus (CCN), which is a small subgroup of oculomotor nucleus containing subnucleus for levator palpebrae superioris.[5] Involvement of this nucleus results in complete, bilateral ptosis. We propose a more detailed evaluation of patients with fluctuating ptosis. In those patients where ptosis is restricted to ocular muscle without any other neuromuscular involvement, cranial imaging needs to be done, preferably MRI of the brain with contrast studies that may show lesions in the midbrain.

Eyelid apraxia associated with deep brain stimulation of the periaqueductal gray area

We report a patient with eyelid apraxia following deep brain stimulation of the periaqueductal gray area. Based on the position of our electrode, we argue that the phenomenon is linked to inhibition of the nearby central caudal nucleus of the oculomotor nucleus by high frequency stimulation.

Delineation of motoneuron subgroups supplying individual eye muscles in the human oculomotor nucleus

The oculomotor nucleus (nIII) contains the motoneurons of medial, inferior, and superior recti (MR, IR, and SR), inferior oblique (IO), and levator palpebrae (LP) muscles. The delineation of motoneuron subgroups for each muscle is well-known in monkey, but not in human. We studied the transmitter inputs to human nIII and the trochlear nucleus (nIV), which innervates the superior oblique muscle (SO), to outline individual motoneuron subgroups. Parallel series of sections from human brainstems were immunostained for different markers: choline acetyltransferase combined with glutamate decarboxylase (GAD), calretinin (CR) or glycine receptor. The cytoarchitecture was visualized with cresyl violet, Gallyas staining and expression of non-phosphorylated neurofilaments. Apart from nIV, seven subgroups were delineated in nIII: the central caudal nucleus (CCN), a dorsolateral (DL), dorsomedial (DM), central (CEN), and ventral (VEN) group, the nucleus of Perlia (NP) and the non-preganglionic centrally projecting Edinger–Westphal nucleus (EWcp). DL, VEN, NP, and EWcp were characterized by a strong supply of GAD-positive terminals, in contrast to DM, CEN, and nIV. CR-positive terminals and fibers were confined to CCN, CEN, and NP. Based on location and histochemistry of the motoneuron subgroups in monkey, CEN is considered as the SR and IO motoneurons, DL and VEN as the B- and A-group of MR motoneurons, respectively, and DM as IR motoneurons. A good correlation between monkey and man is seen for the CR input, which labels only motoneurons of eye muscles participating in upgaze (SR, IO, and LP). The CCN contained LP motoneurons, and nIV those of SO. This study provides a map of the individual subgroups of motoneurons in human nIII for the first time, and suggests that NP may contain upgaze motoneurons. Surprisingly, a strong GABAergic input to human MR motoneurons was discovered, which is not seen in monkey and may indicate a functional oculomotor specialization.

Transient Total Mesencephalic Locked-in Syndrome After Bilateral Ptosis Due To Basilar Artery Thrombosis

Locked-in syndrome (LIS) usually occurs as a result of pontine lesions and has been classified into various categories on the basis of neurologic conditions, of which transient total mesencephalic LIS is extremely rare. A 53-year-old man presented with bilateral ptosis followed by a total locked-in state. In the clinical course, the patient successfully recovered with only left slight hemiparesis and skew deviation remaining. Magnetic resonance imaging revealed multiple ischemic lesions caused by thrombosis at the top of basilar artery, including the bilateral cerebral peduncles, tegmentum of the midbrain, and the right cerebellar hemisphere. Antecedent bilateral ptosis before the locked-in state may be related to ischemia in the central caudal nucleus of the oculomotor nuclei. We should pay attention to this easily missed condition during the treatment of ischemic stroke involving the basilar artery.

Orexin-A inputs onto visuomotor cell groups in the monkey brainstem

Orexin-A, synthesized by neurons of the lateral hypothalamus helps to maintain wakefulness through excitatory projections to nuclei involved in arousal. Obvious changes in eye movements, eyelid position and pupil reactions seen in the transition to sleep led to the investigation of orexin-A projections to visuomotor cell groups to determine whether direct pathways exist that may modify visuomotor behaviors during the sleep-wake cycle. Histological markers were used to define these specific visuomotor cell groups in monkey brainstem sections and combined with orexin-A immunostaining. The dense supply by orexin-A boutons around adjacent neurons in the dorsal raphe nucleus served as a control standard for a strong orexin-A input. The quantitative analysis assessing various functional cell groups of the oculomotor system revealed that almost no input from orexin-A terminals reached motoneurons supplying the singly-innervated muscle fibers of the extraocular muscles in the oculomotor nucleus, the omnipause neurons in the nucleus raphe interpositus and the premotor neurons in the rostral interstitial nucleus of the medial longitudinal fasciculus. In contrast, the motoneurons supplying the multiply-innervated muscle fibers of the extraocular muscles, the motoneurons of the levator palpebrae muscle in the central caudal nucleus, and especially the preganglionic neurons supplying the ciliary ganglion received a strong orexin input. We interpret these results as evidence that orexin-A does modulate pupil size, lid position, and possibly convergence and eye alignment via the motoneurons of multiply-innervated muscle fibres. However orexin-A does not directly modulate premotor pathways for saccades or the singly-innervated muscle fibre motoneurons.

Metastasis to the unilateral oculomotor nucleus complex: case report

This article describes a 76 year old man that, after lung cancer surgery, showed left extrinsic oculomotor paralysis and contralateral paralysis of the superior rectus muscle associated with bilateral ptosis. Magnetic resonance imaging confirmed a rare situation characterized by an isolated metastasis in the region of the left third cranial nerve nucleus, probably compromising the superior rectus subnucleus and the central caudal nucleus, therefore justifying the bilateral oculomotor involvement.

Stretching of the Mueller muscle results in involuntary contraction of the levator muscle.

Since the levator muscle involuntarily and tonically contracts against the weight and elastic resistance of the upper eyelid to maintain an adequate visual field, a mechanoreceptor such as a muscle spindle or a periodontal mechanoreceptor is thought to be essential for its functioning. It was surmised that the Mueller muscle might act as a serial kind of muscle spindle of the levator muscle. The response of the bilateral levator muscles evoked by stretching the Mueller muscle of each eyelid of 87 patients with dermatochalasis or aponeurotic blepharoptosis was electromyographically and photographically recorded. Stretching of the unilateral Mueller muscle evoked contraction of the ipsilateral levator muscle in 18 and of the bilateral levator muscle in 69 of the 87 patients. The Mueller muscle can be thought of as a large, serial kind of muscle spindle, so that stretching by voluntary phasic contraction of the levator muscle for initial eye opening may evoke an afferent impulse to the mesencephalic trigeminal nucleus. Subsequently, this nucleus may stimulate the central caudal nucleus of the oculomotor nuclear complex, leading to involuntary tonic contraction of the ipsilateral or bilateral levator muscles, in the form of a continuous stretch reflex, to maintain an adequate visual field.

Intracranial Fatigable Ptosis

Two patients sought treatment for bilateral fatigable ptosis; one patient had a hematoma, and the other patient had an intracranial metastasis. Compression of the central caudal nucleus in the dorsal midbrain is proposed as the cause of this ptosis, and an alteration of central acetylcholine neurotransmission may contribute to ocular fatigability. Because symptoms that suggest fatigable ptosis can be similar to those that suggest ocular myasthenia gravis, a careful evaluation is necessary to avoid misinterpretation.

Unilateral lid retraction with contralateral oculomotor paresis

A patient is presented with acute onset of partial oculomotor paresis on one side and upper eyelid retraction on the other due to a vascular insult. An electromyographic study revealed frontalis muscle overactivity on the side of lid retraction which has never been documented before, indicating that not only was the supramotor control over the central caudal nucleus affected as previously proposed, but the inhibition of the frontalis muscle motoneurons was also disrupted. Based on these data, a premotoneuronal system is proposed that controls upper eyelid movements by affecting the frontalis muscle and orbicularis oculi muscle motoneurons in addition to the central caudal nucleus.

A retrograde double fluorescent tracing study of the levator palpebrae superioris muscle in the cynomolgus monkey.

In the cynomolgus monkey, motoneurons innervating the levator palpebrae superioris muscle form a nucleus within the oculomotor nuclei called the central caudal nucleus. After double fluorescent neuronal retrograde tracing experiments, using fast blue and diamidino yellow as tracers in the levator palpebrae superior muscles, labelled motoneurons (30%) were found in an unpaired central caudal nucleus. Approximately 2% of the labelled motoneurons were double-labelled. The labelled and double-labelled neurons were distributed randomly over the central caudal nucleus, lateralization of populations of levator motoneurons within this nucleus was not observed. The afferent innervation of the levator palpebrae superioris muscle was restricted to the ophthalmic branch area of the gasserian ganglion. Primary afferent labelled neurons were absent from the mesencephalic nucleus of the fifth nerve. Surprisingly, fast blue was also found in the ophthalmic branch area of the contralateral ganglion of Gasser, while diamidino yellow was present only ipsilaterally. About 1% of the afferent labelled neurons were double-labelled. The results reveal that in the cynomolgus monkey the central caudal nucleus is not only topographically but also functionally one nucleus. Afferent innervation of the levator palpebrae superioris muscle is probably bilaterally organized.

Bilateral Ptosis due to Mesencephalic Lesions with Relative Preservation of Ocular Motility

Three cases of bilateral ptosis with relatively normal ocular motility are presented. In two of the patients, neuroimaging demonstrated lesions in the region of the third cranial nerve subnuclei. These unusual clinical presentations are due to isolated involvement of the central caudal nucleus supplying the bilateral levator muscles, with, virtually complete sparing of other third cranial nerve structures.

Eyelid Lag Without Eyelid Retraction in Pretectal Disease

We report a patient with pretectal eyelid lag without retraction. MRI showed high signal abnormality dorsal to the right red nucleus in a region thought responsible for premotor eyelid control. The dissociation of eyelid lag from eyelid retraction in this patient would suggest that these lid signs may have separate neural mechanisms or pathways. We propose that the lesion interrupts inhibitory connections between the vertical gaze center and the central caudal nucleus.

Bilateral innervation of the musculus levator palpebrae superioris by single motoneurons in the monkey.

The location of motoneurons innervating the musculus levator palpebrae superioris (LPS) was studied in the monkey (Macaca irus) by using Fast blue (FB) and propidium iodide (PI) as retrograde neuronal tracers. In each monkey, FB was injected into the LPS of one eye and PI into the LPS of the other eye. Neuronal cell bodies labeled with FB and/or PI were seen intermixed bilaterally through the entire rostrocaudal extent of the central caudal nucleus. While single-labeled (70%) cell bodies predominated, many double-labeled (30%) cell bodies were also encountered. Each of the double-labeled neurons was concluded to supply the LPS on both sides by way of axon collaterals.

Parasympathetic nuclei

A series of experiments in monkeys using the fluorescent tracer substances Fast Blue and Nuclear yellow as well as wheat germ agglutinin-horseradish peroxidase injected into the ciliary ganglion has demonstrated labeling in 3 distinct regions of the mesencephalon: (1) anterior median nucleus; (2) Edinger-Westphal nucleus of Perlia and (3) the nucleus of Perlia. Further it was shown that the caudal extent of the Edinger-Westphal nucleus reaches the level of the central caudal nucleus of the somatic complex and that the lateral visceral column divided into a major and accessory column at the junction of the middle and posterior one-third of the somatic complex.

Internuclear ophthalmoplegia, prenuclear paresis of contralateral superior rectus, and bilateral ptosis

A patient with infarction of the paramedian part of the lower midbrain on the right side is described, in whom internuclear ophthalmoplegia and bilateral ptosis were associated with limitation of elevation of the contralateral eye from paresis of the superior rectus. Supranuclear paresis was suggested by partial dissociation between phasic and tonic components of upward gaze. It is suggested that the right-sided lesion involved the rostral median longitudinal fasciculus before it reached the oculomotor nucleus, the central caudal nucleus medially situated in the lower end of the oculomotor nucleus, and the prenuclear fibres from the posterior commissure to the ipsilateral nucleus of the contralateral superior rectus. A supranuclear lesion may be suspected when there is a complex association of dysconjugate palsy of oculomotor muscles.