Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0012833 (dizziness)
 9,689 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A short review is given of the pharmacokinetic characteristics and side effects of the nitroimidazoles: metronidazole, tinidazole and ornidazole. The drugs are well absorbed from the gastrointestinal tract, maximum plasma levels generally being obtained 1 to 4 h after oral intake. Metronidazole has been shown to be absorbed after rectal administration; vaginal absorption is documented for all three drugs. The nitroimidazoles are widely distributed in the body, cross the placenta and appear in breast milk. Therapeutically effective concentrations of e.g. metronidazole have been demonstrated in e.g. the central nervous system, middle ear discharges, bile, peritoneal fluid, and fluids and tissues of the female genital tract. The binding to plasma proteins is less than 20%. Available data suggest that the elimination half-lives of these drugs differ, being 7-8 h for metronidazole, about 12 h for tinidazole and 14-15 h for ornidazole. Both metronidazole and ornidazole, but not tinidazole, seem to be extensively metabolized before elimination. The nature and frequency of adverse reactions to this drug include encephalopathy in a few patients treated with doses between 5 and 10 g daily as an adjunct to radiotherapy, and peripheral neuropathy observed in patients treated for prolonged periods with high doses. Among the common side effects of the nitroimidazoles are symptoms from the gastrointestinal tract such as nausea, anorexia, vomiting and metallic or bitter taste. Dizziness, ataxia and headache have been reported. When given together with alcohol, a disulfiram-like intolerance reaction can be obtained.
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PMID:Pharmacokinetics of nitroimidazoles. Spectrum of adverse reactions. 694 57

A growing body of evidence supports the idea that dizziness that persists for months and even years can be caused by an unsuspected perilymphatic fistula. Perilymphatic fistulas are abnormal ruptures that allow perilymph to leak out of the inner ear into the middle ear space. Most commonly, these ruptures occur secondary to a traumatic event. The term postconcussive syndrome has been used to describe a myriad of symptoms following head trauma. Some of these symptoms, such as cognitive changes, tinnitus, neck stiffness, and dizziness, are also commonly caused by active perilymphatic fistulas. This article discusses the typical history and diagnostic tests for patients with perilymphatic fistula. Common diagnostic tests include audiograms, electronystagmograms, electrocochleograms, and subjective and platform fistula tests. Also, the surgical treatment for the perilymphatic fistula (ie, repair of the oval and round windows) is reviewed, along with the results produced by this relatively minor ear operation. Suggestions are made to help the medical professionals involved in rehabilitative care to be aware of perilymphatic fistulas and seek proper consultations from inner ear specialists if they suspect the existence of this easily cured disorder.
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PMID:Persistent dizziness following head trauma and perilymphatic fistula. 748 49

When divers are exposed to extreme atmospheric pressures they may exhibit symptoms of the high pressure nervous syndrome (HPNS). Although clinical HPNS symptoms are well described, little is known about the underlying pathophysiologic mechanisms. Special HPNS signs like vertigo and tremor suggested sensory-motor hyperexcitability resulting from brainstem dysfunction. We therefore studied brainstem auditory evoked potential (BAEP) repeatedly in four divers during an experimental deep helium-oxygen saturation dive to 450 meters of seawater (msw). Wave I (auditory nerve response) latency decreased whereas interpeak latencies (IPLs) I-III and I-V, which indicate respective cochleo-pontine and cochleo-mesencephalic transmission time, prolonged during the dive. IPLs III-V also prolonged the dive, but with greater variability among divers. Two divers showed a marked reversal of the normal attenuation effect of increased stimulus presentation rates on IV and V amplitudes during compression, an effect that subsided during the stay at bottom depth. This finding might indicate a relative enhancement of synaptic excitability and is presumed to be a feature of HPNS. Wave I latency reduction might at least partly be caused by accelerated sound conduction in dense helium. Additionally, an upward shift of middle ear resonance frequencies in helium can induce a basal shift of the main cochlear portion responding to the wide band clicks. This effect may reduce wave I latency due to greater relative input from the basal high frequency-short latency-cochlear neurons. Pressure-induced decrease of nerve conduction velocity, delay of synaptic transmission, and inhibitory modulation of midbrain auditory afferents possibly contributed to observed interpeak latency prolongations. Clinical HPNS signs, such as tiredness, dizziness, postural and intentional hand tremor, ataxia, and opsoclonus, were noted in three divers after reaching 300 msw and continued throughout the 37-h stay at bottom depth.
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PMID:Brainstem auditory evoked potentials during a helium-oxygen saturation dive to 450 meters of seawater. 758 Jul 64

Perilymph fistula is caused by changes of cerebrospinal fluid pressure and/or middle ear pressure. For diagnosis, history taking is extremely important in regard to whether the occurrence of symptoms is related to physical exertion, such as straining, nose blowing, sneezing etc. A variety of symptoms are due to pathologic changes of the membranous labyrinth. Exploratory tympanotomy is needed to verify the occurrence of leakage. However, perilymph fistula cannot be excluded, even if leakage is not observed. Management consists of absolute rest and closure of the fistula. If dizziness or vertigo is intractable and long-lasting, destruction of vestibular function should be considered.
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PMID:Perilymph fistula: concept, diagnosis and management. 807 86

Anatomically, the top portion of the jugular bulb lies just below the floor of the hypotympanum. In rare instances, it can protrude upward and elevate the floor of the hypotympanum thus placing it in the middle ear. Such a case is called high jugular bulb. This anatomical variation has been found in 3.5% to 6% of the temporal bones studied in several reports. But, clinically, only 43 cases have been reported, because in most cases they are asymptomatic. A 17-year-old female was hospitalized with right hearing disturbance and dizziness. Neurootological examination revealed sensory neuronal hearing disturbance. A caloric test was scaled out. Axial bone window CT scan demonstrated an enlarged jugular bulb and an extended upward projecting hypotympanum. MRI indicated flow void in the same region. Retrograde jugulography has been the most useful method for diagnosis but we were able to diagnose it by noninvasive MR angiography. High jugular bulb is an unfamiliar disease entity for neurosurgeons, but we should remember that it is one of the differential diagnosis for c-p angle regions or jugular foramen regions.
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PMID:["High jugular bulb": clinical feature, radiographical findings and differential diagnosis, a case report]. 874 12

Cholesterol granulomas of the head are relatively rare. Isolated lesions of the cerebellopontine angle are even more uncommon. In this report, 17 cases of petrous apex cholesterol granulomas are presented and management is discussed. Symptoms at presentation included dizziness (14 patients), pressure (nine patients), tinnitus (eight patients), hearing loss (eight patients), otalgia (six patients), headache (six patients), nausea (three patients), drainage from ear (two patients), facial pain (two patients), seizure (two patients), lightheadedness (one patient), hemifacial spasm (one patient), and facial numbness (one patient). Six cases were managed without surgery and 11 patients underwent operative procedures. The approaches used included the infralabyrinthine (eight patients), transcanal-infracochlear (two patients), and translabyrinthine (one patient). The mean follow-up period for all cases was 29.5 months. Of those patients managed without surgery, symptoms improved in all except one, whose tinnitus was slightly worse. Of surgically treated patients, symptoms improved or remained the same except in one with worsened dizziness. There were nine patients with hearing present presurgery and seven whose hearing was preserved postsurgery. The authors present a case that was managed at another center where an attempt at surgical resection through a subtemporal middle fossa approach was unsuccessful. This lesion was successfully treated using an infralabyrinthine approach with drainage into the mastoid cavity. Cholesterol granulomas of the petrous apex can be managed without surgery when symptoms are stable or improve. Otherwise, a transmastoid extradural approach with simple drainage into the mastoid sinus or middle ear produces symptomatic improvement with low morbidity. Resection of petrous apex cholesterol granulomas is not necessary.
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PMID:Cholesterol granulomas of the petrous apex: combined neurosurgical and otological management. 881 66

In recent years in the literature on stapes surgery several changes have been proposed concerning the adoption either of new technologies (Laser) or of surgical techniques preserving middle ear functional structures (stapedoplasty). The Authors carried out a personal case-report on 30 patients suffering from otospongiotic disease, in order to clarify the real advantages and possible applications of the latest developments in small fenestra stapedectomy. Twenty subjects underwent platinotomy with preservation of the stapedial tendon (stapedoplasty), while a simple stapedotomy was performed in the remaining 10 cases, with or without inversion of surgical times (a "rigid system" technique was adopted in 7 patients). CO2 Laser was used on 10 of these patients (33%) in order to carry out certain surgical steps; in particular it was used on 7 subjects who underwent stapedotomy with stapedoplasty (35%) and in 3 cases of traditional stapedotomy (100%). An audiometric examination was conducted on all subjects 1 and 6 months after the operation, in order to evaluate functional recovery; the post-operative stapedial reflex was also studied in patients who underwent stapedoplasty. This research points out the advantages that CO2 Laser gives in the execution of stapes surgery, whatever the type of technique adopted; in particular, the advantages of using this instrument are: -an easier and bloodless performance of the operation, particularly in the case of the preservation of the stapedial tendon; -a greater regularity and precision of the footplate hole than that obtained by drilling, especially in subjects whose stapes are thin, floating, fractured or even obliterated; -less mechanical traumatism on the labyrinth during either the fracturing of the crura or the footplate fenestration, resulting in the reduction of both perceptive hearing loss an dizziness; -a higher incidence of air-bone gap closure mostly in the case of stapedial tendon preservation. On the other hand, the use of inadequate lasers or the lack of reference to exact parameters (beam power and frequence, time of exposure and defocalization), could cause the heating of labyrinthine liquids and so damage the receptorial structures of the inner ear.
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PMID:[Evolution of the operative technique. CO2 laser stapedotomy and stapedoplasty]. 892 68

The use of local anaesthesia for middle ear surgery is long established and has many advantages. However, it is only performed by a small number of UK otolaryngologists (20%). This lack of enthusiasm is due to concerns that patients may not tolerate the discomfort during the operation. Therefore, a survey was conducted on patients who had middle ear operations: stapedotomy, myringoplasty, ossiculoplasty and mastoidectomy. The intense sensation of noise during the operation (29.6% of patients) and anxiety (24%) were the most common discomforts, followed by dizziness (14.8%), backache (13.9%), claustrophobia (9.3%) and earache (1.9%). In spite of these discomforts, 89% of patients still preferred local anaesthesia to general anaesthesia for a similar procedure. The author suggests that good patient selection, pre-operative explanation and the use of appropriate sedation are the important factors for local anaesthesia ear procedures to be acceptable to patients.
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PMID:Local anaesthesia in middle ear surgery: survey of patients and surgeons. 893 43

Vertigo and dizziness are not common complaints in childhood, but probably present more often than has been thought. These symptoms, caused mainly by otitis media (OM) and middle ear effusion (MEE), are 2 of the most common diseases in children, and until recently had long been neglected in the literature and in practice. We determined objectively the incidence of balance-related symptoms in children with long-lasting MEE, and resolution following insertion of ventilation tubes (VT). 36 children, aged 4-9 years, were studied using electronystagmography (ENG) and the Bruininks-Oseretsky tests for motor proficiency, before and after ventilation of the middle ear. Results were compared to those in 74 healthy children with no history of middle ear disease. Abnormal ENG findings were found in 58%, and 71% had low Bruininks-Oseretsky (BO) test scores. The ENG was abnormal in only 3 of the controls, 1 of whom also had low BO test scores. The symptoms and signs of balance disturbances resolved in 96% following VT insertion. These results indicate that balance-related symptoms often encountered in young children may result from chronic MEE, and that they resolve following evacuation of the effusion and ventilation of the middle ear.
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PMID:[Balance disturbances in children with middle ear effusions]. 945 89

Vertigo and dizziness are not common in childhood, but are probably present more often than was formerly thought. These symptoms caused mainly by o700is media and middle ear effusion, two of the most common diseases in children, have been neglected for a long time, both in the literature and in practice, until recently. The purpose of this study was to determine objectively the incidence of balance-related symptoms in children with long-lasting middle ear effusion and to discover whether these symptoms resolve after the insertion of ventilation tubes. One hundred thirty-six children, ages 4 to 9 years, were given electronystagmographic tests and the Bruininks-Oseretsky tests for motor proficiency before and after tube ventilation of the middle ear. The results were compared with those in 74 healthy children with no history of middle ear diseases. Pathologic findings were found in 58% of the children with chronic middle ear effusion, as compared with only 4% of the control group. The symptoms and signs of balance disturbances resolved in 96% of the children after ventilation tube insertion. The results of this study indicate that balance-related symptoms often encountered in young children may result from chronic middle ear effusion and that these symptoms will resolve after evacuation of the effusion and ventilation of the middle ear.
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PMID:Simple, new device for needle aspiration biopsy. 985 52


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