[Olfactory dysfunction : Update on diagnosis and treatment]. / Riechstörungen : Update zur Diagnostik und Therapie.

Olfactory dysfunction is a common disorder, particularly in elderly people. From the etiologic point of view, we distinguish between sinunasal and non-sinunasal causes of dysosmia. As an important early symptom of neurodegenerative disease, dysosmia is particularly relevant in the diagnosis of Parkinson's or Alzheimer's disease. In addition to complete ENT examination and olfactory testing, e.g., with "Sniffin' Sticks", modern imaging procedures, e. g. MRI, are becoming more and more important for diagnostics, prognosis, and treatment decisions. Olfactory testing in children needs to be adapted to their shorter concentration span and limited range of known olfactory stimuli. Depending on the etiology, olfactory training, antiphlogistic measures, and surgical procedures are most promising. In cases of intracranial causes of dysosmia, neurosurgeons should know and respect anatomic structures of the olfactory signal pathway, not least for long-term prognosis.

[Dysosmia : current aspects of diagnostics and therapy]. / Riechstörungen : Aktuelles zur Diagnostik und Therapie.

Olfactory dysfunction is a common disorder, especially in elderly people. From the etiological point of view a differentiation is made between sinunasal, traumatic and non-sinunasal causes of dysosmia. Olfactory disorders are often observed in neurodegenerative diseases, especially in patients with Parkinson's disease or Alzheimer's disease. Apart from an extensive medical history important diagnostic tools are a complete ear nose and throat (ENT) examination including nasal endoscopy and olfactory testing, for example, with "sniffin' sticks". For diagnostic purposes modern imaging procedures, such as magnetic resonance imaging (MRI) are becoming more and more important. For testing children, olfactory testing needs to be adapted and depending on the etiology, olfactory training, antiphlogistic and surgical procedures are the most promising therapeutic approaches. In cases of intracranial causes of dysosmia neurosurgeons should know and respect the anatomical structures of the olfactory signal pathway, not least for the long-term prognosis.

Is there a correlation between hippocampus and amygdala volume and olfactory function in healthy subjects?

Both amygdala (AG) and hippocampus (HC) are integral parts of the olfactory system. The present study, including a large number of healthy subjects, was performed to compare HC and AG volumes, measured by manual tracing, in relation to specific olfactory functions, including odor threshold, discrimination, identification, and odor memory tasks. It also aimed to provide age-related normative data about the volume of the HC and AG. A total of 117 healthy volunteers participated (age range 19-77 years, mean age 37 years; 62 women, 55 men). Using the "Sniffin' Sticks", subjects received lateralized tests for odor threshold, and odor discrimination. In addition, an odor memory and an odor identification task were performed bilaterally. A Mini-Mental-State test excluded dementia. MR scans were performed using a 1.5 T scanner for later manual volumetric measurements. Volumetric measurements exhibited a good reproducibility. The average volume for the right HC was 3.29 cm(3) (SD 0.47), for the left HC it was 3.15 cm(3) (SD 0.47). The average right AG had a volume of 1.60 cm(3) (SD 0.31), left 1.59 cm(3) (SD 0.3). Increasing age was accompanied by a decrease of HC and AG volumes, which were much more pronounced for the right compared to the left side. Only the volume of the right HC showed a small but significant correlation with odor threshold (r(117)=0.21; p=0.02). Importantly, this correlation was not mediated by age as indicated by the significant partial correlation when controlling for age (r(114)=0.18; p=0.049). In conclusion, the present data obtained in a relatively large group of subjects demonstrates a small correlation between the volume of the HC, as an integral part of the olfactory system, and smell function. In addition, these data can be used as the basis for normative values of HC and AG volumes, separately for men, women and different age groups. This is of potential interest in diseases with acute or chronic impairment of olfactory function, in metabolic or neurodegenerative diseases or in disorders with damage of areas involved in adult neurogenesis.

Expanding the clinical and neuroradiological phenotype of 6q27 microdeletion: olfactory bulb aplasia and anosmia.

Subtelomeric deletions of chromosome 6q may result in a syndrome with brain malformations, comprising hydrocephalus and hypoplasia of the corpus callosum. Aplasia of the olfactory bulbs (OB) or anosmia has not been described in this syndrome. We describe a 3-year-old girl and a 25-year-old man with subtelomere 6q deletions. Both patients had aplastic OB and hydrocephalus. Subtelomeric 6q deletions might be underdiagnosed as anosmia can be the only symptom.

Correlation between olfactory bulb volume and olfactory function in children and adolescents.

The olfactory bulb (OB) is considered to be the most important relay station in odor processing. The present study aimed to investigate the volumetric development of the human bulb and the olfactory function during childhood and youth. Furthermore, the present study aimed to investigate a possible correlation between OB volume and specific olfactory functions including odor threshold, odor discrimination and odor identification. A total of 87 subjects (46 boys, 41 girls), aged 1-17 years (mean age 8 years), participated in this study. None of them reported olfactory dysfunction or had signs of a dysfunctional sense of smell. Whenever possible, participants received a volumetric scan of the brain and lateralized olfactory tests. Volumetric measurements of the right and left OB were taken by manual segmentation of the coronal slices through the OB. Significant correlations between OB volumes and olfactory function were observed. Both, OB volumes and olfactory function increased with age, although the correlation between structure and function was not mediated by the subjects' age. In conclusion, for the first time, the present study showed a correlation between OB volume and olfactory functions in children.

Acquired sensorimotor polyneuropathy in an adolescent boy with primary intracranial sarcoma.

Acquired polyneuropathies (PN) are rare in childhood and adolescent. We report on a 15-year-old male patient who presented with progressive gait instability, ataxia, neuropathic pain, distal muscle weakness and progressive loss of ambulation. Nerve conduction studies (NCS) revealed a progressive demyelinating sensorimotor polyneuropathy predominantly of the lower limbs. Cerebrospinal fluid (CSF) analyses revealed a cytoalbuminologic dissociation. Extensive diagnostic workup for autoantibodies and inflammatory markers was inconclusive. Corticosteroids and intravenous immunoglobulins did not affect. Cranial MRI revealed leptomeningeal enhancement of the cerebellum and the brainstem. Brain biopsy of the cerebellar lesions revealed an unclassifiable sarcoma. The patient was treated according to the CWS guidance study resulting in a decrease in enhanced lesion size. After two years NCS still revealed a demyelinating sensorimotor PN. This case report describes for the first time the clinical course of a chronic PN, putative paraneoplastic, associated with isolated unclassifiable CNS-sarcoma in an adolescent patient. Paraneoplastic pathogenesis should be considered in an unusual sequence of subacute progressive neurological symptoms even in children and adolescents.

Correlation between olfactory bulb volume and olfactory function.

The olfactory bulb (OB) is considered to be the most important relay station in odor processing. Involving 125 randomly selected subjects (58 men, 67 women; age range: 19 to 79 years), the present study aimed to investigate a possible correlation between OB volume and specific olfactory functions including odor threshold, odor discrimination, and odor identification. The history of all participants was taken in great detail to exclude possible causes of smell dysfunction. All participants received an otolaryngological investigation including a volumetric scan of the brain (MRI), lateralized olfactory tests and a screen for cognitive impairment. Volumetric measurements of the right and left OB were performed by manual segmentation of the coronal slices through the OB. Significant correlations between OB volumes in relation to olfactory function were observed, independent of the subjects' age. Additionally, OB volumes decreased with age. In agreement with previous research the present study confirmed the correlation between OB volume and specific olfactory functions. Furthermore, the correlation between OB volume and olfactory function was not mediated by the subjects' age. In conclusion, the present data obtained from a relatively large group of subjects forms the basis for age-related normative values of OB volumes.

Changes of olfactory processing in childhood and adolescence.

OBJECTIVES: Olfactory event-related potentials (OERPs) are widely used to study central odor processing. Only a few studies used this method in children and adolescents. Aim of the current study therefore was to measure OERP and the possible influences of age and sex on central odor processing in this age group. METHODS: A total of 81 children between 6 and 17 years of age were included in this study. OERP in response to a rose-like odor were measured from three recording positions (Fz, Cz, Pz) according to the 10-20 system. Stimuli were presented by means of a computer-controlled olfactometer. RESULTS: Age had a significant influence on the amplitudes of the late positivity with younger children showing larger amplitudes. Although age did not significantly affect the latencies of OERP, interactions of recording positions and latencies between younger and older children and between girls and boys were found. CONCLUSIONS: OERP can be used to study central odor processing in children older than 6 years of age. Central odor processing changes from childhood to adolescents possibly reflecting maturation of the brain.

Novel frameshift mutation in the CACNA1A gene causing a mixed phenotype of episodic ataxia and familiar hemiplegic migraine.

Episodic ataxia type 2 (EA2, MIM#108500) is the most common form of EA and an autosomal-dominant inherited disorder characterized by paroxysmal episodes of ataxia. The disease causative gene CACNA1A encodes for the alpha 1A subunit of the voltage-gated P/Q-type calcium channel. We report on a family with a novel mutation in the CACNA1A gene. The clinical symptoms within the family varied from the typical clinical presentation of EA2 with dysarthria, gait ataxia and oculomotor symptoms to migraine and dystonia. A novel nonsense mutation of the CACNA1A gene was identified in all affected family members and is most likely the disease causing molecular defect. The pharmacological treatment with acetazolamide (AAA) was successful in three family members so far. Treatment with AAA led to a reduction of migraine attacks and an improvement of the dystonia. This relationship confirmed the hypothesis that this novel mutation results in a heterogeneous phenotype and confutes the coincidence with common migraine. Dystonia is potentially included as a further part of the phenotype spectrum of CACNA1A gene mutations.

Olfactory bulb ventricles as a frequent finding in magnetic resonance imaging studies of the olfactory system.

UNLABELLED: Background. In some species an embryologic cavity inside the olfactory bulb (OB) persists and is called olfactory bulb ventricle (OBV). It is generally assumed that OBVs in humans are solitary findings representing remnants of embryologic structures that were not fully regressed, although the incidence of OBVs was never examined. Using magnetic resonance imaging (MRI), the present study aimed to study the incidence of OBVs in healthy human subjects. Material and methods. A total of 122 individuals participated. Volumes of the right and left OB were determined using MRI scans and a standardized protocol for OB analysis. For comparison, OBs of 42 cadavers were collected and sectioned. Results. The main finding of this study was the high incidence of OBV-like structures in our study group. Seventy-two out of 122 (59%) participants yielded signs for an OBV whereas three out of 42 postmortem OBs contained histologically detectable OBV. DISCUSSION: This stands in disagreement with the previous assumption of complete obliteration at the time of birth. This discrepancy may be explained by the fact that our present findings are based on modern MRI techniques with much higher resolution than 10 or 20 years ago. Another possible explanation for the discrepancy between studies based on MRI and histopathology might relate to postmortem resorption of cerebrospinal fluid from OBVs. Especially with a long postmortem interval OBVs may collapse and may no longer appear as an open cavity.

[The TV head ophthalmoscope for videodocumentation of fundus changes]. / Das TV-Kopfophthalmoskop zur Videodokumentation von Fundusveränderungen.

The present paper describes the TV head ophthalmoscope, a logical further development in indirect ophthalmoscopy. It comprises a modern indirect binocular head ophthalmoscope and a micro-CCD color camera. The instrument enables all structures on the fundus to be observed as far as the periphery. Objects seen dynamically include detached retina and vitreous membranes. Practical fields of application are retinal detachment surgery and for demonstration and training in indirect ophthalmoscopy.

[Intra-arterial fluorescein angiography using ophthalmic artery catheter in an experimental model]. / Intraarterielle Fluoreszenzangiographie mittels Arteria-ophthalmica-Katheter im Modell.

BACKGROUND: For the purpose of retinal angiography sodium fluorescein can be applied oral, intravenously or, via special catheters, intraarterially. In the latter procedure the imaging is different, which will be examined in this paper. There come up aspects, which supplement the possibilities of conventional sequence- or videoangiography and contrast the experimental technique of angiography by temperature-sensitive liposomes. MATERIAL AND METHODS: Intraarterial retinal angiography was carried out on 15 rabbits through a microcatheter and fluorescein was applied in different quantities and concentrations. RESULTS: Because of the direct inflow to the retina, the resulting images had more contrast and interference due to recirculating fluorescein was nearly excluded. With increased perfusion pressure, functional tests of circulation were possible. By administering small amounts of fluorescein 10% (0.01-0.02 ml/min) via the catheter, continuous perfusion provided continuous presentation of hemodynamics, by making visible retinal pulsation. CONCLUSIONS: The intraarterial fluorescence-angiography offers a new possibility for evaluating retinal circulation under increased pressure and for analysis of the retinal pulse wave. The procedure gets a clinical perspective by combined therapeutical application.