Laryngeal varices: an atypical cause of globus

Laryngeal varices are rare and are usually associated with vocal cord trauma secondary to excessive use of voice. This report is the first documented case of laryngeal varices secondary to thyroid goitre. This is a report of an 83-year-old woman with a known retrosternal goitre chiefly with symptoms of globus. Retrosternal goitre was found to be compressing the pharyngeal venous plexus causing laryngeal venous structures bilaterally to be engorged along the aryepiglottic folds, arytenoids, posterior commissure and extending in to the postcricoid region. The presence of laryngeal varices carries a significant increased risk of haemorrhage. This case presents an atypical presentation of globus and the first reported case in the literature of laryngeal varices secondary to a thyroid goitre.

Understanding Parinaud’s Syndrome

Parinaud’s syndrome involves dysfunction of the structures of the dorsal midbrain. We investigated the pathophysiology related to the signs and symptoms to better understand the symptoms of Parinaud’s syndrome: diplopia, blurred vision, visual field defects, ptosis, squint, and ataxia, and Parinaud’s main signs of upward gaze paralysis, upper eyelid retraction, convergence retraction nystagmus (CRN), and pseudo-Argyll Robertson pupils. In upward gaze palsy, three structures are disrupted: the rostral interstitial nucleus of the medial longitudinal fasciculus (riMLF), interstitial nucleus of Cajal (iNC), and the posterior commissure. In CRN, there is a continuous discharge of the medial rectus muscle because of the lack of inhibition of supranuclear fibers. In Collier’s sign, the posterior commissure and the iNC are mainly involved. In the vicinity of the iNC, there are two essential groups of cells, the M-group cells and central caudal nuclear (CCN) group cells, which are important for vertical gaze, and eyelid control. Overstimulation of the M group of cells and increased firing rate of the CCN group causing eyelid retraction. External compression of the posterior commissure, and pretectal area causes pseudo-Argyll Robertson pupils. Pseudo-Argyll Robertson pupils constrict to accommodation and have a slight response to light (miosis) as opposed to Argyll Robertson pupils were there is no response to a light stimulus. In Parinaud’s syndrome patients conserve a slight response to light because an additional pathway to a pupillary light response that involves attention to a conscious bright/dark stimulus. Diplopia is mainly due to involvement of the trochlear nerve (IVth cranial nerve. Blurry vision is related to accommodation problems, while the visual field defects are a consequence of chronic papilledema that causes optic neuropathy. Ptosis in Parinaud’s syndrome is caused by damage to the oculomotor nerve, mainly the levator palpebrae portion. We did not find a reasonable explanation for squint. Finally, ataxia is caused by compression of the superior cerebellar peduncle.

Brainstem and Cranial Nerves: Midbrain

The midbrain (or mesencephalon) is the uppermost segment of the brainstem. This chapter reviews the important structures in the midbrain, including cranial nerves III and IV. The midbrain extends from the level of the trochlear nucleus to an imaginary line between the mammillary bodies and the posterior commissure. Important structures at this level include the cerebral peduncles, superior and inferior colliculi, red nucleus, substantia nigra, decussation of the middle cerebellar peduncle, and cranial nerves III and IV.

Baska Mask Failure: Culprit Resides at the Posterior Commissure

The article's abstract is not available.

A rapidly growing cardiac calcified amorphous tumour diagnosed after coronary artery bypass graft surgery: a case report

Background A cardiac calcified amorphous tumour (CAT) is a non-neoplastic intracavitary cardiac mass. The most serious complication is systemic embolism. Cardiac CATs tend to be surgically resected immediately after detection; therefore, its progress of growth is rarely reported. Case summary An 83-year-old Japanese woman received on-pump beating coronary artery bypass graft surgery (CABG) for angina pectoris. Transthoracic echocardiography (TTE) performed preoperatively and 1 month postoperatively revealed the presence of mitral annular calcification, with no other abnormal findings. However, follow-up TTE performed 5 months after CABG revealed a mobile nodular mass (5.0 × 8.2 mm) in the left ventricular outflow tract. At 1 month after detection, the mass had enlarged to 5.0 × 13.0 mm. Transoesophageal echocardiography revealed that the pedunculated high-echoic mass was adhered to the posterior commissure of the mitral valve and was dynamically swinging towards the non-coronary cusp in the systolic phase. As the mass had grown rapidly in less than 6 months, it was surgically resected to prevent systemic embolism. The histological specimen consisted mainly of fibrin, including calcification and hemosiderin deposition, which lead to a diagnosis of cardiac CAT. The patient had an uneventful postoperative course during her hospital stay and had no evidence of recurrence for 1 year after discharge. Discussion This was a rare case in which a rapidly growing cardiac CAT was detected following on-pump CABG. Cardiac CATs may grow very rapidly and therefore early surgery should be considered after initial diagnosis.

Direct Targeting of the Anterior Nucleus of the Thalamus via 3 T Quantitative Susceptibility Mapping

Objective: Deep brain stimulation (DBS) of the anterior nucleus of the thalamus (ANT) is a potentially effective, minimally invasive, and reversible method for treating epilepsy. The goal of this study was to explore whether 3 T quantitative susceptibility mapping (QSM) could delineate the ANT from surrounding structures, which is important for the direct targeting of DBS surgery.Methods: We obtained 3 T QSM, T1-weighted (T1w), and T2-weighted (T2w) images from 11 patients with Parkinson’s disease or dystonia who received subthalamic nucleus (STN) or globus pallidus interna (GPi) DBS surgery in our center. The ANT and its surrounding white matter structures on QSM were compared with available atlases. The contrast-to-noise ratios (CNRs) of ANT relative to the external medullary lamina (eml) were compared across the three imaging modalities. Additionally, the morphology and location of the ANT were depicted in the anterior commissure (AC)-posterior commissure (PC)-based system.Results: ANT can be clearly distinguished from the surrounding white matter laminas and appeared hyperintense on QSM. The CNRs of the ANT-eml on QSM, T1w, and T2w images were 10.20 ± 4.23, 1.71 ± 1.03, and 1.35 ± 0.70, respectively. One-way analysis of variance (ANOVA) indicated significant differences in CNRs among QSM, T1w, and T2w imaging modalities [F(2) = 85.28, p < 0.0001]. In addition, both the morphology and location of the ANT were highly variable between patients in the AC–PC-based system.Conclusion: The potential utility of QSM for the visualization of ANTs in clinical imaging is promising and may be suitable for targeting the ANT for DBS to treat epilepsy.

DeepNavNet: Automated Landmark Localization for Neuronavigation

Functional neurosurgery requires neuroimaging technologies that enable precise navigation to targeted structures. Insufficient image resolution of deep brain structures necessitates alignment to a brain atlas to indirectly locate targets within preoperative magnetic resonance imaging (MRI) scans. Indirect targeting through atlas-image registration is innately imprecise, increases preoperative planning time, and requires manual identification of anterior and posterior commissure (AC and PC) reference landmarks which is subject to human error. As such, we created a deep learning-based pipeline that consistently and automatically locates, with submillimeter accuracy, the AC and PC anatomical landmarks within MRI volumes without the need for an atlas. Our novel deep learning pipeline (DeepNavNet) regresses from MRI scans to heatmap volumes centered on AC and PC anatomical landmarks to extract their three-dimensional coordinates with submillimeter accuracy. We collated and manually labeled the location of AC and PC points in 1128 publicly available MRI volumes used for training, validation, and inference experiments. Instantiations of our DeepNavNet architecture, as well as a baseline model for reference, were evaluated based on the average 3D localization errors for the AC and PC points across 311 MRI volumes. Our DeepNavNet model significantly outperformed a baseline and achieved a mean 3D localization error of 0.79 ± 0.33 mm and 0.78 ± 0.33 mm between the ground truth and the detected AC and PC points, respectively. In conclusion, the DeepNavNet model pipeline provides submillimeter accuracy for localizing AC and PC anatomical landmarks in MRI volumes, enabling improved surgical efficiency and accuracy.

A clinical study on laryngotracheal injuries following endotracheal intubation

<p class="abstract"><strong>Background:</strong> Despite major advances in the design of endotracheal tubes and developments in the management of difficult airways, endotracheal intubation remains by far the most common cause of laryngotracheal injuries (LTI). These LTI are challenging to manage and are associated with significant morbidity and mortality. Hence, the present study was done to find out the incidence, types of LTI and to study the factors affecting the same.</p><p class="abstract"><strong>Methods:</strong> A prospective study was conducted on patients who were intubated for more than 48 hours and admitted in medical intensive care units in a tertiary referral hospital, for a period of 1 year. All patients following extubation were evaluated for LTI by x-ray neck (antero-posterior and lateral view), rigid endoscopy and flexible naso-pharyngo-laryngoscopy. </p><p class="abstract"><strong>Results:</strong> Thirty patients were included in the study. Majority of the patients (56.6%) were found normal while 43.2% patients were having LTI following extubation in the form of bilateral vocal cord fixation, subglottic stenosis, granulation tissue in the posterior commissure and in the trachea. Majority of these patients were aged less than 45 years, with duration of intubation for more than 10 days, with tube size more than 7 mm. Organo-phosphourous (OP) poisoning was the etiology for LTI in 69.2% cases.</p><p class="abstract"><strong>Conclusions:</strong> A high incidence of LTI especially in cases of OP poisoning warrants one to be cautious in managing these intubated patients. Those patients requiring prolonged intubation should be considered for other alternative airway managements like tracheostomy in addition to using low pressure, high volume cuffed tubes. Adequate training of the emergency personnel in the intubation technique and its subsequent care is important especially in a tertiary referral center.</p>

Syndrome of one and middle of the vertical look: possible clinical entity associated with percheron artery ischemia: semiological and neuroanatomic aspects

Context: The acute paralysis of the vertical gaze is usually caused by a mesencephalic lesion because the control of the vertical conjugated gaze is found there; there are three main structures: the rostral interstitial nucleus of the medial longitudinal fascicle (riFLM), the Cajal interstitial nucleus and the posterior commissure (CP). The riFLM, contains burst neurons responsible for the saccades, projecting to the subnuclei of the upper rectum and inferior oblique to look upwards and subnuclei of the lower rectum and superior oblique to look downwards. The projections for the elevators appear to be bilateral, with axons probably crossing within the oculomotor nuclear complex and apparently not via CP; depressors, on the other hand, are ipsilateral. Case report: Female, 78 years old, hypertensive and diabetic, suddenly started with vertical diplopia and vertigo. Examination: Bilateral hypoactive photomotor reflex, bilateral paralysis of the vertical gaze upward, monocular paralysis downward and torsional nystagmus in the left eye. Resonance with restriction the diffusion of water molecules in both thalamus and in the right rostral midbrain. Conclusions: riFLM is vascularized by the posterior thalamus-subthalamic paramedian artery. A single artery, Percheron’s, provides both riFLM in 20% of the population and allows bilateral lesions from a single infarction. Unilateral infarction can also cause saccadic paralysis of the bilateral vertical gaze. The disjunctive disorders of the vertical gaze have two variants of the one and a half syndrome. One consists of bilateral paralysis of the gaze upwards and monocular paresis of the gaze downwards with an ipsilateral or contralateral lesion, described in thalamomesencephalic lesions, explanation for the exposed case. The other is due to bilateral mesodiencephalic infarctions. It is difficult to understand the relationship between topography and the vertical gaze circuit, showing that it is more complex than we imagine. It is probably an association of topographies, little described, but of paramount importance to be discussed and researched.

Dr. М. Probst. Experimental investigations on the end of the loop, the hood tracks, the dorsal longitudinal bundle and the posterior commissure Arch. F. Psychiatry and Nervous Diseases, Vol. 33, Issue. 1, 1900

The author dulit his work into 4 sections: T. About the end of the loop, II. On the running and ending of some tire systems (Haubenbndel), III. About fibers of the posterior longitudinal fascicle, IV. To learn about the posterior spike. The work was carried out on cats and dogs in the laboratory des Landes-Irren-Anstalt in Wien; the brains of the operated animals were processed by the Marchi method.