Phantosmia
This hallucination is intrinsically suspicious as the formal evaluation and detection of relatively low levels of odour particles is itself a very tricky task in air epistemology.
It can result from neurological conditions such as migraines, head injuries, strokes, Parkinson's disease, seizures, or brain tumors.
[4] If the problem persists or causes significant discomfort, a doctor might recommend nasal saline drops, antidepressant or anticonvulsant medications, anesthesia to parts of the nose, or in very rare circumstances, surgical procedures to remove the olfactory nerves or bulbs.
The occurrence of depression resulted from the severe symptoms of phantosmia as everything even food smelled spoilt, rotten and burnt for these patients.
[11] In 2011 Coleman, Grosberg and Robbins did a case study on patients with olfactory hallucinations and other primary headache disorders.
[14] The central explanation is that active or incorrectly functioning cells of the brain cause the perception of the disturbing odor.
[15] Other studies on phantosmia patients have found that the perception of the odor initiates with a sneeze, thus they avoid any nasal activity.
[3] Several patients who have received surgical treatment have stated that they have a feeling or intuition that the phantom odor is about to occur, however it does not.
This sensation has been supported by positron emission tomography, and it has been found that these patients have a high level of activity in their contralateral frontal, insular and temporal regions.
In both cases, instances of olfactory delusions are more common, especially in Alzheimer's, where it is exceedingly difficult to convince the patient that these are in fact hallucinations and not real.
As evidenced in trauma and seizures, phantosmia is strongly associated with this area; leading to its appearance in some Alzheimer's patients.
[16] Neuroblastoma is a rare form of a malignant cancer which can start in the olfactory nerve, which is responsible for smell sensation.
[17] The complaints of phantosmia involving the perception of unpleasant odors most commonly include "burnt", "foul", "rotten", "sewage", "metallic" or "chemical".
The most challenging task for the examiner is to determine and obtain the correct symptoms and associate them with one of the olfactory disorders, as there are several of them and they are related to each other.
After determining the nature of the disorder, and confirming phantosmia, the examiner must then have the patient describe their perception of the phantom odor.
[14] Although these may be events that have resulted in the phantom odor, studies conducted by Zilstrof have found that the majority of phantosmia patients have no previous history of head trauma and upper respiratory infections.
Also, due to being a poorly understood disorder, and having analogies to some psychiatric conditions, some patients are told that they have a mental illness.
[21][22] But a counter-argument by Leopold, Loehrl and Schwob (2002) has stated that this ablation process results in a bilateral permanent anosmia and includes risks associated with a craniotomy.
(Duncan and Seidan, 1995) A case involving long term phantosmia has been treated with the use of an anti depressive medication by the common name Venlafaxine (Effexor).
The most commonly used treatment method is the removal of the olfactory epithelium or the bulb by means of surgery to alleviate the patient from the symptoms.
[3] Another treatment option is the topical solution of cocaine HCl which also provides relief for a short time period by acting as an anesthetic and desensitizing the nasal neurons.
This topical solution can have several side effects as it has been found that some patients with troposmia started to show symptoms of phantosmia after its use.
The olfactory hallucination reported by the woman was an unpleasant mixture of vinegar, fecal material, and rotten eggs.
She was prescribed medications including nasal steroid sprays and other drugs, but they would not relieve her of her headaches and phantosmia symptoms.
[citation needed] The patient was successfully treated with a surgical procedure involving permanent disruption of the olfactory epithelium.
This excision was meant to sever all the fila olfactoria entering the central nervous system from her left nostril.
Five weeks after surgery, the woman reported a complete absence of her phantosmia symptoms, and her olfactory ability was maintained (Hornung et al.
When her family doctor prescribed her the antidepressant venlafaxine, she noticed that the drug resulted in the complete elimination of her phantosmia symptoms.
While the patient was treated for her tremors with pramipexole, amantadine hydrochloride, levodopa, carbidopa and entacapone, the phantosmia symptoms disappeared completely.
She later began to experience the typical symptoms of phantosmia and would smell things that she could recognize in the absence of any odor producing molecules.
