Proteomic Characterization of the Olfactory Molecular Imbalance in Dementia with Lewy Bodies.

Olfactory dysfunction is one of the prodromal symptoms in dementia with Lewy bodies (DLB). However, the molecular pathogenesis associated with decreased smell function remains largely undeciphered. We generated quantitative proteome maps to detect molecular alterations in olfactory bulbs (OB) derived from DLB subjects compared to neurologically intact controls. A total of 3214 olfactory proteins were quantified, and 99 proteins showed significant alterations in DLB cases. Protein interaction networks disrupted in DLB indicated an imbalance in translation and the synaptic vesicle cycle. These alterations were accompanied by alterations in AKT/MAPK/SEK1/p38 MAPK signaling pathways that showed a distinct expression profile across the OB-olfactory tract (OT) axis. Taken together, our data partially reflect the missing links in the biochemical understanding of olfactory dysfunction in DLB.

El COVID-19 también Afecta el Sistema Nervioso por una de sus Compuertas: El Órgano Vascular de la Lámina Terminal y el Nervio Olfatorio. Alerta Neurológica, Prueba de Disosmia o Anosmia Puede Ayudar a Un Diagnóstico Rápido / COVID-19 also Affects the Nervous System by One of its Gates: The Vascular Organ of Lamina Terminalis and the Olfactory Nerve. Neurological Alert, Dysosmia or Anosmia Test Can Help to A Quick Diagnosis

Se presenta una breve revisión de órgano vascular de la lámina terminal (organum vasculosum laminae terminalis) y el nervio olfatorio, el primero un elemento neuroanatómico hipotalámico relacionado con la producción de hormona antidiurética y su asociación como una vía potencial de invasión del COVID-19 al sistema nervioso central, afectando la regulación fisiológica de liberación de hormonas relacionadas con la homeostásis del sodio. También se vincula el neurotropismo de este virus al asociarse con el nervio olfatorio, una evaginación del cerebro en la que se altera su funcionalidad por generación de disosmia entre otras características neurosemiológicas. Se plantea la necesidad de advertir a los profesionales de la salud en general y a los neurólogos en especial, sobre las potenciales alteraciones neurológicas relacionadas con esta pandemia antes y después del contagio de este virus e implementar una prueba olfatoria rápida con ácido acético, incluso antes de otras valoraciones como hipertérmia, tos y cefalalgia.

First recognized n-butanol concentration may be simple and useful index for assessing olfactory dysfunction in geriatric patients.

The KVSSII is widely used to evaluate olfactory function in the Korean population. We evaluated the usefulness of the first recognized n-butanol concentration, which is obtained at the beginning part of KVSS II, in predicting olfactory dysfunction. Three hundred seventy two subjects were enrolled in our study. The results of KVSS II and the demographic characteristics were statistically analyzed. The first recognized n-butanol concentration was positively correlated with the result of KVSS II. The mean value of first recognized n-butanol concentration was 5.59 ± 1.42 in normosmia, 4.10 ± 1.40 in hyposmia, and 0.84 ± 1.68 in the anosmia group. By ROC curve, cut-off value of 2.5 showed sensitivity of 85.9% and specificity of 90.6% for anosmia, and cut-off value of 4.5 showed sensitivity of 77.6% and specificity of 69.8% for hyposmia. Consequently, we suggest that it may be useful in assessing olfactory function, in geriatric patients who are not able to tolerate conventional KVSS II.

[Diagnosis of olfactory disorders]. / Diagnostik bei Riechstörungen.

Alongside a structured case history, the measurement of olfactory function and diagnosis of olfactory dysfunction is of great clinical importance. Validated and established methods have been developed to this aim. The "Sniffin' Sticks" test battery is an easy-to-use tool for assessing olfactory function. Recording of olfactory event-related potentials is a more objective approach, which is particularly important in medicolegal cases. Imaging techniques such as MRI and CT provide additional information in the diagnosis of olfactory disorders. The latter techniques enable the anatomical structures of the skull and brain with the areas relevant to olfactory function to be evaluated.

The olfactory system.

Any dysfunction in olfaction requires a radiological exploration comprising the nasal cavity, the anterior base of the skull, in particular the frontal and temporal lobes. MRI is the reference examination, due to the frontal plane and the T1, T2 volume maps. In the child, aplasia of the olfactory bulbs falls within a polymalformation (CHARGE) or endocrine (Kallman) context. In the adult, rhino sinus disease and meningiomas are the most common etiologies. Frontal or temporal impairment: tumoral or vascular and neurodegenerative disorders (Parkinson's disease) may accompany a loss of olfaction.

[Olfactory ensheathing cell tumour: case report and literature review]. / Tumor de las células envolventes del olfatorio: caso clínico y revisión de la literatura.

Olfactory ensheathing cells are glial cells located in the olfactory bulb and nerve. Microscopically, both olfactory ensheathing cells and Schwann cells have similar morphological and immunohistochemical features. However, olfactory ensheathing cells are negative for Leu-7(CD-57), whereas Schwann cells are positive. We present the case of a 49 year-old male with a history of visual impairment and hyposmia. Radiological CT and MRI studies showed a subfrontal cystic extra-axial mass, which eroded the right cribriform plate, with heterogeneous contrast enhancement. Total excision of the tumour was performed by bifrontal craniotomy. Histological examination initially suggested a schwannoma, with immunohistochemical staining being positive for S-100 protein and negative for epithelial membrane antigen (EMA). However, the tumour was negative for Leu-7. Accordingly, the final diagnosis was olfactory ensheathing cell tumour. Herein, we describe the sixth case of intracranial olfactory ensheathing cell tumour and stress the important role of immunohistochemical techniques in obtaining a definitive diagnosis.

Distorted olfactory perception: a systematic review.

The sense of smell provides people with valuable input from the chemical environment around them. The human sense of smell generally fails in three ways; one is an intensity reduction and the other two are the quality of changes. Smell disorders can be classified into central or peripheral depending on their origin. Central causes can be related to an area of hyper-functioning brain cells generating this odor perception, thus olfactory distortions have also been observed with epilepsy and migraine. In this paper, we present a review of the current clinical understanding of olfactory distortions and discuss how they can be evaluated and therapies to treat this debilitating condition.

Imaging the olfactory tract (cranial nerve #1).

This review paper browses pros and cons of the different radiological modalities for imaging the olfactory tract and highlights the potential benefits and limitation of more recent advances in MR and CT technology. A systematic pictorial overview of pathological conditions affecting olfactory sense is given. Techniques for collecting quantitative data on olfactory bulb volume and on olfactory sulcus depth are described. At last, insights into functional imaging of olfactory sense are shown.

Development of guideline for rating the physical impairment of otolaryngologic field.

We develop a guideline for rating the physical impairment of otolaryngologic fields. Assessment of hearing disturbance and tinnitus required physical examination, pure tone audiometry, speech audiometry, impedance audiometry, brainstem evoked response audiometry, Bekesy audiometry, otoacoustic emission test, and imaging examination. History taking, physical examination, and radiological examination for the vestibular organ and brain, righting reflex test, electronystagmography, and caloric test are taken for evaluation of balance disorder. Olfactory function tests include University of Pennsylvania Smell Identification test, Connecticut Chemosensory Clinical Research Center test, T and T olfactometry and Korean Version of Sniffin's Sticks test. Medical history and physical examination is mandatory to evaluatezseverity of respiration difficulty. Examinations include flexible fiberoptic nasopharyngoscope, bronchoscopy, simple soft-tissue radiography films of upper airway and high resolution computed tomography. Evaluation of mastication and swallowing are history taking, physical examination, examination for upper jaw, lower jaw, and temporomandibular joint, dental examination and radiological studies. Endoscopy and esophagography are also needed. Voice disorder is evaluated based on physical examination, oral pharynx and larynx endoscopy, larynx stroboscopy, hearing assessment, laryngeal electromyography, sound analysis test, aerodynamic test, electroglottography, and radiologic examination. Articulation disorder is assessed by picture consonant articulation test. These are position articulation test, Lee-Kim Korean articulation picture and speech intelligibility assessment.

[Diagnosis of olfactory disorders--clinical standards and research]. / Diagnostik von Riechstörungen--Standards und Forschung.

Olfactory dysfunction has been reported to affect about 79,000 patients who were treated annually in German ORL-hospitals. The incidence of olfactory dysfunctions emphasizes the need for diagnostic strategies. This article features on the dysfunction of human olfaction including neurodegenerative diseases. Standard procedures for the psychophysical and objective assessment of olfactory function are presented. Current diagnostic imaging techniques for routine use and scientific approaches are discussed.

Olfactory schwannoma.

We report a case of olfactory schwannoma with calcification. Intraoperative findings indicated that the tumour originated from the olfactory groove. Intraoperative findings of previous studies have not indicated a clear relationship between subfrontal schwannoma and the olfactory nerve, which seems strange, given the association between tumours and cranial nerves at other sites. We suggest this observation has not been reported because the growing olfactory schwannoma changes the local morphology, affecting the appearance of the olfactory nerve.

[Olfactory groove schwannoma: case report]. / Schwannoma da goteira olfatória: relato de caso.

Intracranial schwannoma not related to cranial nerves are unusual and rarely found in the subfrontal region. We report a case of olfactory groove schwannoma in a 27-year-old male, who presented with anosmia and headache initiated one year ago. At admission, bilateral papilledema was noted with absense of motor deficits or cranial nerves abnormalities. Cranial computed tomography (CT) revealed a bifrontal multicystic isodense enhancing mass lesion causing a frontal ventricular horn compression. Radiological features resembled that of a cystic olfactory groove meningioma. Decompressive bifrontal craniotomy was done. One month later, CT demonstrated a homogeneously contrast-enhancing mass in the olfactory groove region who extended into the left nasal cavity. Magnetic resonance imaging did not add more informations. A second surgical procedure was done through a nasoethmoidal approach with incomplete resection of the lesion. The complete tumor resection was only possible in a third surgery through another bifrontal approach. The hystopathological diagnosis of schwannoma was performed by conventional methods and confirmed by immunohistoquemical staining for S-100 protein. The rarity of this tumor and his clinical, radiological and histological aspects justify this publication.

Olfactory neuroepithelioma arising from the olfactory placode.

The patient was a 54-year-old man, who had lost his sense of smell 6 years previously and had started to become forgetful about 6 months prior to presenting at hospital. MRI admission showed a large multicystic tumor with Gd-DTPA enhancement extending from the anterior cranial fossa through the sphenoid sinus and into the nasal cavity. Histopathological examination revealed extensive proliferation of small round cells that were divided by connective tissue septae. The tumor cells occasionally formed tubular structures, although no basement membranes were present. On immunostaining, round tumor cells were positive for neuron-specific enolase, synaptophysin, and chromogranin A, while cells forming tubules were positive for AE 1 and CAM 5.2. Almost all of the tumor cells were positive for Ber-EP4, and some of the epithelioid cells surrounding the tubular structures were also positive for luteinizing hormone-releasing hormone (LH-RH). Electron microscopy demonstrated sporadic intercellular junctions, many microtubules in the tumor cell processes, and clear- and dense-cored vesicles in the cytoplasm. Based on the results, this case appears to be the first documented neuroepithelioma with Ber-EP4- and LH-RH-positive cells arising from the olfactory placode.

A mobile high-field magnetic resonance system for neurosurgery.

OBJECT: The authors' goal was to place a mobile, 1.5-tesla magnetic resonance (MR) imaging system into a neurosurgical operating room without adversely affecting established neurosurgical management. The system would help to plan accurate surgical corridors, confirm the accomplishment of operative objectives, and detect acute complications such as hemorrhage or ischemia. METHODS: The authors used an actively shielded 1.5-tesla magnet, together with 15 mtesla/m gradients, MR console computers, gradient amplifiers, a titanium, hydraulic-controlled operating table, and a radiofrequency coil that can be disassembled. The magnet is moved to and from the surgical field by using overhead crane technology. To date, the system has provided unfettered access in 46 neurosurgical patients. In all patients, high-definition T1- and/or T2-weighted images were rapidly and reproducibly acquired at various stages of the surgical procedures. Eleven patients underwent craniotomy that was optimized after preincision imaging. In four patients who harbored subtotally resected tumor, intraoperative MR imaging aided the surgeon in removing the remaining tumor. Interestingly, the intraoperative administration of gadolinium demonstrated a dynamic expansion of enhancement beyond the preoperative contrast contour in patients with malignant glioma. These zones of new enhancement proved, on examination of biopsy samples, to be tumor. CONCLUSIONS: The authors have demonstrated that high-quality MR images can be obtained in the operating room within reasonable time constraints. Procedures can be conducted without compromising or altering traditional neurosurgical, nursing, or anesthetic techniques. It is feasible that within the next decade intraoperative MR imaging may become the standard of care in neurosurgery.