|An Online Compendium of News & Science||September 18, 2014|
Disorders of Odor Perception offers links to the latest science and news about olfactory dysfunction. It is updated frequently. Newest items are at the top of each column.
Anosmia & Hyposmia
Odor identification deficits correlated with multisystem neurodegeneration in Parkinson's disease. Read more.
Damage to orbitofrontal cortex reduces odor identification and discrimination but not detection in a 40-year-old female. Read more.
Mutations in FEZF1 gene may be responsible for Kallmann syndrome and its associated anosmia. Read more.
Chemotherapy for childhood leukemia has no effect on odor perception or size of olfactory bulbs. Read more.
X-linked mutation in olfactory cyclic nucleotide gated channel subunit CNGA2 found in brothers with congenital anosmia. Read more.
Smell function but not quality of life tracks disease severity in rhinosinusitis. Read more.
Odors activate brain areas associated with fear response in patients with panic disorder. Read more.
Study provides normative values for an olfactory test battery in Turkey. Read more.
In older adults with mild cognitive impairment, better visual and verbal memory is linked to reduced likelihood of severe hyposmia. Read more.
Hyposmia and two other symptoms can help identify Parkinson's disease in its prediagnostic phase. Read more.
Intact olfaction in patients with longstanding parkinsonism may indicate a non-idiopathic Parkinsons's disease pathology. Read more.
No effect of MAO-B inhibitor rasagiline on olfactory function in Parkinson's disease. Read more.
Case reports of unusual transient anosmia during acute phase electroconvulsive therapy. Read more.
MRI and SPECT imaging have high sensitivity and specificity in diagnosis of olfactory dysfunction in head trauma; even better when combined. Read more.
Smell and taste function impaired in patients with inflammatory bowel disease. Read more.
Beta-amyloid deposition in olfactory system is potential molecular marker for early diagnosis of Alzheimer's disease. Read more.
Hyperbaric conditions increase olfactory thresholds but have no effect on odor discrimination or identification. Read more.
Patients with Bardet-Biedl syndrome score in microsmic range on test of odor identification. Read more.
Impaired odor identification in schizophrenia not likely the result of semantic processing deficits. Read more.
Congenital anosmics have thicker cortex in higher order olfactory processing areas of the brain. Read more.
Olfactory deficits in mild cognitive impairment predict conversion to Alzheimer's dementia. Read more.
Severity of colonic Lewy neuropathology is independent of odor identification impairment in Parkinson's disease. Read more.
Sensory and electrophysiological measures of olfaction may predict transition to psychosis in clinical high-risk individuals. Read more.
Pilot study finds intranasal theophylline treatment safer and more effective than oral delivery for treatment of hyposmia. Read more.
Chemical analysis validates gas-phase odor concentrations in scented pens used for olfactory identification. Read more.
Odor identification impairment in obsessive-compulsive disorder correlates with impaired motor implusivity. Read more.
MRI study of Parkinson's disease finds microstructual damage to olfactory tracts. Read more.
Screening of 12 odorants recommends four for inclusion in UK-specific odor identification test. Read more.
Odor valence but not intensity influences olfactory identification ability in patients with, and at risk for, schizophrenia. Read more.
Odor identification lower in Parkinson's disease patients than controls but not correlated to olfactory bulb size. Read more.
Multicenter study shows benefits of training with high concentration odors in recovery from post-infectious smell loss. Read more.
Large study of schizophrenic patients links poorer olfactory performance to symptom severity. Read more.
Impaired olfactory function associated with poorer cognitive function in middle-aged people. Read more.
Olfactory and other non-motor symptoms more common in old-age onset Parkinson's disease patients. Read more.
Carriers of a TRPA1 ion channel variant show increased sensitivity to both smells and pain. Read more.
MRI study reveals gray matter loss in olfactory processing areas of a congenitally anosmic boy. Read more.
Smell training may reduce olfactory deterioration in older people. Read more.
Cisplatin chemotherapy reduces pleasantness of food odors in bronchial cancer patients. Read more.
Series of 100 cases finds no significant change in olfactory status following rhinoplasty. Read more.
Sodium channel mutations that increase nociception also increase odor sensitivity. Read more.
Swimming exercise improves olfactory rehabilitation in laryngectomy patients. Read more.
Smell training improves odor perception in patients with post-traumatic and post infectious olfactory dysfunction. Read more.
Utility of a brief smell test in a multi-ethnic bilingual cohort. Read more.
Routine MRI for isolated idiopathic olfactory loss may be unwarranted due to very low diagnostic yield. Read more.
Reduced olfactory function in patients with bulimia and anorexia. Read more.
Anosmia may be a symptom of superficial siderosis in post-traumatic brain injury. Read more.
Sniffin' Sticks reveal effect of educational level on olfaction in Turkish population. Read more.
Pathological attitudes toward eating predict reduced odor sensitivity. Read more.
Combined course of oral and nasal corticosteroids improves smell in severe sino-nasal polyposis. Read more.
Atrophy of gray and white matter in olfactory brain areas corresponds to duration of anosmia. Read more.
Preserving smell after endoscopic sinus surgery via medialization of the middle nasal turbinate. Read more.
Regular exercise may reduce risk of olfactory impairment in older adults. Read more.
Factors affecting post-operative smell function in surgery for olfactory groove meningioma. Read more.
Comparison of odor identification tests in evaluation of Parkinson's disease patients in India. Read more.
Smell identification ability tracks cognitive and behavioral symptoms of Alzheimer's disease. Read more.
Case report of anosmia following exposure to a pyrethrin-based insecticide. Read more.
Decreased smell and taste function confirmed in series of patients with total laryngectomy. Read more.
Olfactory dysfunction more severe and prevalent in eosinophilic than noneosinophilic chronic rhinosinusitis. Read more.
Olfactory outcomes after endoscopic sinus surgery in patients with eosinophilic vs noneosinophilic chronic rhinosinusitis. Read more.
Olfactory deficits in depressed women return to normal following psychotherapy. Read more.
Perception of odor intensity is intact in schizophrenic patients, but hedonic judgements show increased range during acute episodes. Read more.
Spinal anesthesia does not appear to alter performance on a brief test of smell identification. Read more.
Positive link between olfactory improvement and quality of life following treatment for chronic sinusitis and allergic rhinitis. Read more.
Russian study examines olfactory dysfunction in sinusitis patients, pregnant women and schizophrenic patients. Read more.
Study of 201 healthy Dutch children extends normative data for Sniffin' Sticks screening test to pediatric ENT population. Read more.
Survey of patients in a geriatric day hospital finds olfactory function not linked to nutritional status. Read more.
Olfactory dysfunction associated with anxiety, depression and reduced quality of life in rhinitis patients. Read more.
Korean national health survey finds olfactory dysfunction in 4.5% of population; identifies several risk factors. Read more.
Study confirms diagnostic value of smell testing in Parkinson's disease; find three odors that separate patients from controls. Read more.
Radiation therapy for head and neck cancer reduces odor sensitivity and identification ability. Read more.
Case presentation of a patient with anosmia and bilateral polypoid masses in the olfactory clefts. Read more.
Severe hyposmia predicts dementia in patients with Parkinson's disease. Read more.
Olfactory training improves odor discrimination, identification and sensitivity in Parkinson's disease patients. Read more.
Decreased olfaction part of a characteristic neurobehavioral profile in Bardet-Biedl syndrome. Read more.
Smell loss in normal aging is associated with diffuse degenerative changes in brain structure. Read more.
Heavy prenatal alcohol exposure associated with impaired odor identification ability in children. Read more.
Blood chemistry measures associated with performance on Barcelona Smell-Taste Test-24 in adult diabetes patients. Read more.
Upper respiratory tract infections leading cause of olfactory dysfunction in series of 140 Chinese ENT patients. Read more.
Naturally cycling women more sensitive to musk-type odors near ovulation than are women taking oral contraceptives. Read more.
Case report of craniofacial fibrous dysplasia presenting initially as olfactory dysfunction. Read more.
Impaired olfactory function and reduced olfactory bulb volume in patients with temporal lobe epilepsy. Read more.
Interleukin 6 is elevated in patients with hyposmia. Read more.
Olfactory dysfunction found in patients with idiopathic intracranial hypertension. Read more.
Unilateral odor sensitivity and discrimination correlate positively with unilateral olfactory bulb volume. Read more.
Childhood maltreatment associated with reduced olfactory function and olfactory bulb volume in depressed adults. Read more.
Odor detection and identification abilities are reduced in patients with multiple sclerosis. Read more.
Anosmia associated with weaker executive function in traumatic brain injury. Read more.
Parkinson disease deficits on new Japanese smell test correlate with Hoehn and Yahr stages. Read more.
Olfactory impairment reduces migration of thallium-201 from nasal epithelium to olfactory bulb. Read more.
Semi-structured interviews with traumatic brain injury patients show smell loss impacts a range of activities and social roles. Read more.
Sensory testing fails to confirm self-reported enhanced smell acuity in fibromyalgia patients. Read more.
Male congenital anosmics have fewer sexual relationships; females experience reduced security about their partner. Read more.
A majority of cytis fibrosis patients exhibit smell loss, with sensitivity affected more than odor identification. Read more.
New odor discrimination test differentiates anosmics from malingerers. Read more.
Analysis of 3,400 patients reveals that age and sex patterns of olfactory loss vary according to the cause. Read more.
Trauma as a cause of nasal issues including smell loss in athletes. Read more.
Improved olfactory function after nasal sinus surgery but not after nasal septum surgery. Read more.
Reduced odor recognition ability in Japanese patients with Parkinson's disease, Alzheimer's disease and myotonic dystrophy. Read more.
Reduced odor identification ability associated with disease severity and weight loss in Parkinson's disease patients. Read more.
Hyposmia in Parkinson's disease is associated with pupillary and cardiovascular parasympathetic dysfunction. Read more.
Olfactory impairment in patients with posterior cortical atrophy resembles that seen in Alzheimer's disease. Read more.
African Americans more likely to suffer from presbyosmia even after potential confounding variables are taken into account. Read more.
Temporal lobe resection in patients with temperal lobe epilepsy results in impaired olfactory function. Read more.
An olfactomotor task reveals implicit olfactory processing in traumatic brain injury patients with anosmia. Read more.
Odor identification deficits observed in fragile X tremor ataxia syndrome (FMR1 premutation carriers). Read more.
ERP brain activation measure shows functional olfactory decline in Alzheimer's disease much earlier than previously observed. Read more.
Nasal nitric oxide levels do not differ between various etiologies of smell loss. Read more.
Profound olfactory dysfunction reported in patients with myasthenia gravis. Read more.
Hyposmia and other nonmotor symptoms may differentiate Parkinson's disease from drug-induced parkinsonism. Read more.
Olfactory bulb volume measured by MRI may predict recovery from post-infectious and post-traumatic smell loss. Read more.
Odor identification ability in multiple sclerosis patients is negatively correlated with severity of white matter lesions. Read more.
Chinese Parkinson's disease patients score lower on smell identification test than do healthy controls. Read more.
Retrospective study of 425 patients with olfactory dysfunction suggests some benefit from systemic corticosteroids. Read more.
Decreased smell function in seasonal allergic rhinitis may be due to inflammation of the epithelium more than the airway obstruction caused by the inflammation. Read more.
Odor identification deficits observed in adolescents chronically exposed to ferro-manganese emissions. Read more.
Ovarian cancer patients undergoing platinum-containing chemotherapy may experience transient olfactory impairment. Read more.
Mild hyposmia observed in familial ataxias may be due to cognitive deficits rather than specifically olfactory impairment. Read more.
Pilot study finds differences in the time course of food appreciation between congenital anosmics and normal controls. Read more.
Daily Vitamin A therapy failed to improve recovery in patients with postinfectious and posttraumamtic smell loss. Read more.
Daily odor training plus topical corticosteroid treatment improves olfactory performance in a range of smell dysfunctions. Read more.
Levels of cAMP and cGMP in patients' parotid saliva vary with etiology of smell and taste disorder. Read more.
Self-assessed olfactory ability is reliable in smell-impaired patients but not in healthy controls. Read more.
Patients with traumatic brain injury are more likely to have deficits in empathy and affect recognition if they also have impaired olfaction. Read more.
By recording intrinsic optical signals from the olfactory epithelium, researchers detect neural response to odor in some functionally anosmic patients. Read more.
A large-scale population study finds olfactory impairment in 0.6% of those under 35 and in 13.9% of those 65 or older. Read more.
In mice with experimentally-induced nasal inflammation, mucus shows elevated K+ and lowered Na+. Nasal irrigation with similar ion concentrations reduces olfactory sensitivity in humans. Read more.
A 57-year-old woman develops anosmia and hypogeusia after abdominal surgery under general anesthesia. Recovers fully in 6 months. Read more.
Sense of smell improves in patients with persistent allergic rhinitis after treatment with levocetirizine. Read more.
A 3-year study finds that severe hyposmia is a significant risk factor for subsequent dementia in Parkinson's disease patients. Read more.
A long-term study of patients with posttraumatic olfactory disorders finds improved function as much as 74 months after trauma. Read more.
Case report: brain surgery to remove a temporoinsular glioma spared the olfactory tracts but resulted in permanent anosmia. Read more.
ER docs at New York's Bellevue Hospital present a case of coup and contrecoup head injury resulting in anosmia. Read more.
Compared to age-matched controls, 32 congenital anosmics showed enhanced social insecurity and increased risk of depressive symptoms and household accidents. Read more.
An electronic nose can detect degredation over time in odors used to test patients for anosmia and hyposmia. Read more.
A patient with extensive bilateral damage to the limbic system shows profound impairments in odor identification and recognition. Read more.
A French team has developed the Lyon Clinical Olfactory Test. It differentiates between anosmia and hyposmia, perception and identification deficits, and Alzheimer's and hyposmic patients. Read more.
Monell Center researchers have developed a scratch-and-sniff smell test using pictures which is suitable for children as young as three years of age. Read more.
A study of 413 patients in Taiwan with olfactory dysfunction examined quality of life issues and emotional coping. The impact of smell loss was greatest in younger patients. Read more.
A study using a brief smell test examined 283 African American aged 55-87. Age and sex predicted scores on the smell test, but education and chronic illness status did not. Read more.
Compared to matched controls, alchoholics showed deficits in odor identification, as well as abnormalities in brain wave response to smells. Read more.
An Individual Importance of Olfaction Questionnaire was given to 235 anosmic or hyposmic patients, and 235 people with normal smell function. Results showed lower scores for anosmics vs. hyposmics, and for smell disorder patients vs. normosmics. Read more.
Norwegian researchers examined odor perception in 240 middle-aged and elderly people. Unawareness of olfactory dysfunction was high in both groups and associated with poorer cognitive performance. Read more.
Australian researchers find that olfactory impairment in people 70 years and older is associated with an elevated odds ratio for depressive symptoms. Read more.
German researchers discover that a misfunctioning gene encoding a voltage-gated sodium channel is responsible for the inability to feel pain as well as for congenital anosmia. Experiments with genetically altered mice confirm the result. Read more.
Parosmia, Dysosmia, Cacosmia & Phantosmia
Parosmia and phantosmia are enhanced in patients with severe depression. Read more.
Significant prevalence of olfactory hallucinations in Parkinson's disease. Read more.
No long-term benefit to topical cocainization as a treatment for phantosmia. Read more.
Patient complaining of bad body odor suffering from olfactory delusional syndrome rather than phantosmia. Read more.
Odor source localization less accurate in schizophrenic patients with olfactory hallucinations. Read more.
Case study of cacosmia associated with fungal dacryocystitis. Read more.
Halitosis-like phantosmia experienced by two young patients undergoing radiation therapy for brain tumors. Read more.
Case report of unilateral cacosmia associated with maxillary sinus fungal infection. Read more.
Case report of complex olfactory hallucinations during a migraine attack in a 17-year-old patient. Read more.
Despite expense, MRI imaging is cost-effective in the workup of idiopathic dysosmia. Read more.
Schizophrenic patients have altered hedonic responses to the smell of amyl acetate. Read more.
Changes in odor perception during major depressive episode persist after clinical improvement of depression. Read more.
Osmophobia is common in Taiwanese migaineurs and linked to higher anxiety and depression scores. Read more.
Olfactory reference syndrome in a patient with Parkinson's disease. Read more.
A study links olfactory hallucinations in schizophrenia to specific neuropsychological impairments. Read more.
A case report of Olfactory Reference Syndrome discusses proposed changes to the DSM-V classification. Read more.
Olfactory hallucinations may be a significant non-motor symptom in Parkinson's disease. Read more.
Schizophrenic patients with olfactory hallucinations more likely to have olfactory habituation deficits and past episodes of brief unconsciousness. Read more.
Case report of subacute combined degeneration of the spinal cord and a novel dysosmia. Read more.
An unusual case of migraine headache associated with olfactory hallucinations in a patient with post-traumatic anosmia. Read more.
Activation of subdural electrodes implanted near the olfactory bulb in epileptic children produce olfactory hallucinations. Read more.
A case report of long lasting phantosmia that disappeared under anti-depressive treatment with venlafaxine. Read more.
Case report of headaches in a migraine patient induced by a Valsalva manoeuvre she used to relieve persistent cacosmia. Read more.
Large Chinese study characterizes olfactory and trigeminal event-related potentials in hyposmic and anosmic patients. Read more.
Olfactory hallucinations in headache typically last 5 to 60 minutes, occur shortly before or with the onset of head pain, and consist of a highly specific unpleasant odor. Read more.
A review of the current clinical understanding of olfactory distortions and how to evaluate them. Read more.
A case report from Ceylon of a soldier in his early thirties diagnosed with Olfactory Reference Syndrome, on the basis of an imagined smell of urine in the absence of actual urinary incontinence. Read more.
Australian psychologist R.J. Stevenson examines the evidence for olfactory illusions and the reasons they may escape awareness. Read more.
The body locations that most frequently preoccupy patients with Olfactory Reference Syndrome are mouth (75%), armpits (60%) and genitals (35%). Read more.
A review of all 84 case studies of Olfactory Reference Syndrome published since 1891 reveals that a majority of patients are male with an age of onset <20 years. Read more.
Brain areas involved in odor quality discrimination and odor memory are reduced in size in parosmic patients. Read more.
Progress reported on structured clinical questions that differentiate parosmics from healthy persons and patients with phantosmia. Read more.
Two surgeons draw attention to cases of parosmia after laparoscopic gastric bypass and gastric banding. Read more.
News & Reviews
How variation in olfactory receptor genes contributes to individual differences in odor perception. Read more.
A review of olfactory deficits and other features of different hypogonadotropic hypogonadal syndromes. Read more.
A review of olfactory neuropathology in Alzheimer's disease. Read more.
Interdisciplinary team speculates about olfactory measures to diagnose and treat infant malnutrition. Read more.
A smell and taste clinic reviews findings from 5,183 patients examined over a 40-year span. Read more.
A review of Machado-Joseph disease notes olfactory dysfunction as one of its nonmotor, extracerebellar features. Read more.
A first-person account of congenital anosmia by a philosopher is included in a special smell issue of The Anatomical Record. Read more.
Humans can discriminate as many as one trillion odors, far more than previously thought. Read more.
A comprehensive review suggests links between smell function and autoimmune disease. Read more.
A systematic review of chemosensation in myasthenia gravis recommends olfactory testing in this disorder. Read more.
A literature review places olfactory dysfunction among the non-cognitive symptoms of Alzheimer's disease. Read more.
A review of smell and taste disorders for the primary care physician. Read more.
A review of olfactory and taste function in autism spectrum disorders. Read more.
A review of olfactory disorders for the clinical rhinologist covers quality of life issues and pathophysiology processes. Read more.
Review of 26 articles finds that osteitis in chronic rhinosinusitis is associated with reduced olfaction. Read more.
Yale study examines possible mechanisms underlying effects of aging on the olfactory system, suggests new research directions. Read more.
Systematic review of 22 studies of smell and taste alterations in chemotherapy patients draws no firm conclusions. Read more.
Literature reviews finds that olfactory dysfunction is an early sign of neurodegenerative disease. Read more.
Revised Portuguese language version of widely used smell test validated in Brazilian population sample. Read more.
Review of olfaction in physiology and disease finds olfactory dysfunction to be clinically significant and likely to grow in prevalence. Read more.
Large-scale review of scientific literature finds olfaction key to human evolution and quality of life. Read more.
A review of plasticity and neurogenesis in the human olfactory system, focusing on the olfactory bulb. Read more.
Subjective and objective effects on quality of life assessed in 1,000 patients with olfactory dysfunction. Read more.
A review of the genetics, diagnosis, and treatment of Kallmann syndrome in women. Read more.
Literature review of olfaction in affective and anxiety disorders reveals mixed results. Read more.
A review of olfaction in child and adolescent psychiatric disorders finds changes in function in disorders with dopaminergic pathology. Read more.
Canadian researchers review the decline in smell and taste in Alzheimer's disease and stroke with attention to its nutritional consequences. Read more.
Italian researchers review neurological diseases preceded or accompanied by olfactory dysfunction. Read more.
The Wall Street Journal's Ellen Byron describes ways to fight age-related decline in the sense of smell. Read more.
Filmmaker and congenital anosmic Jacob LaMendola creates a short film featuring people with acquired and congenital anosmia. View it here.
Two otolaryngologists review for plastic surgeons the importance of conducting pre-operative baseline smell testing. Read more.
A brief review of the olfactory system and its disorders by a leading smell researcher. Intended for a neurological audience. Read more.
A review of findings that olfactory loss and conditions such as parosmia are associated with a reduction in olfactory bulb volume. Read more.
Richard Doty reviews the neurobiology of smell loss in Parkinson's disease. Read more.
Two researchers at the VCU School of Medicine review the possibility of olfactory epithelial transplantation as a means of restoring smell. Read more.
Disorders of Odor Perception is updated frequently. Items are entered chronologically with newest items at the top of each column.
Disorders of Odor Perception offers links to the latest science and news about olfactory dysfunction. It does not endorse the material on the linked sites, nor does it offer medical advice. For medical advice about disorders of smell, consult your physician.
Copyright 2014 by Synesthetics, Inc.