Objective Using olfactory event related potentials(OERP) and magnetic resonance to evaluate olfactory function in patients with posttraumatic anosmia. Methods Twenty four patients with posttraumatic anosmia were reviewed retrospectively. A thorough medical history,physical examination,nasal endoscopy,T&T olfactory testing,olfactory event-related potentials,brain computed tomography scan and magnetic resonance image of olfactory pathway were performed in all patients. Results Subjective olfactory testing indicated 20 of 24 patients were birhinal anosmia. 2 with right nostril anosmia and left impairment,2 with left anosmia and right normal. No OERP were obtained in 24(20 were birhinal,4 was monorhinal),except 4 cases with single nostril. Magnetic resonance imaging revealed the injures to the olfactory bulbs(100%),rectus gyrus(91.7%),orbital gyrus(67%),olfactory tracts(8%) and temporal lobes(8%). Conclusions OERP can objectively evaluate posttraumatic olfactory function,and magnetic resonance of olfactory pathway can precisely identify the location and extent of injures.

OBJECTIVETo report on a series of patients with congenital anosmia, and to discuss its classification and clinical characteristics.

METHODSEight patients with congenital anosmia were reviewed retrospectively. Four of eight cases were congenital anosmia with other abnormalities, including three cases with Kallmann's syndrome, one with hypoplasia of nasal cavity and nasal sinus. Four cases were isolated congenital anosmia. A thorough medical and chemosensory history, physical examination, nasal endoscopy, T&T olfactory testing, olfactory event-related potentials and sinonasal computed tomography scan were performed in all patients. Magnetic resonance image of olfactory pathway was available in seven cases, and olfactory biopsies were done in two cases.

RESULTSAll patients reported had never been able to smell anything. ENT physical examination and nasal endoscopy were normal, except one case with hypoplasia of nasal cavity. Subjective olfactory test indicated all of them were anosmia. No olfactory event-related potentials to maximum stimulus were obtained. Magnetic resonance imaging revealed the absence of olfactory bulbs and tracts in six cases, hypoplasia of bilateral olfactory bulbs and tracts in one case. Computed tomography scan indicated normal except hypoplasia of nasal cavity and sinus in one case. Three cases with Kallmann syndrome showed poor development of both primary and secondary sexual characteristics and had decreased serum luteinizing hormone, follicle-stimulating hormone, testosterone and estradiol.

CONCLUSIONSDiagnosis of congenital anosmia is established on chief complain, physical examination, nasal endoscopy, olfactory testing and olfactory imaging. Magnetic resonance imaging of olfactory pathway is indispensable.

Adolescent ; Adult ; Child ; Female ; Humans ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Olfaction Disorders ; classification ; diagnosis ; Olfactory Pathways ; pathology ; Retrospective Studies ; Tomography, X-Ray Computed ; Young Adult