guide words: plethysmography; pulmonary function tests; spirometry; vocal cords Abbreviations: Gaw = airway conductance; MVV = maximal voluntary ventilation; Palv = alveolar pressure; Pbox = plethysmographic chest pressure; Raw = airway resistance; Vaw = airway flow; VCD = vocal cord dysfunction ********** Herein we existing a patient with dyspnea and dysphonia.

guide words: plethysmography; pulmonary function tests; spirometry; vocal cords

Abbreviations: Gaw = airway conductance; MVV = maximal voluntary ventilation; Palv = alveolar pressure; Pbox = plethysmographic chest pressure; Raw = airway resistance; Vaw = airway flow; VCD = vocal cord dysfunction

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Herein we existing a patient with dyspnea and dysphonia, who had previously received a diagnosis of asthma and was treated for asthma, further the final diagnosis of vocal cord dysfunction (VCD) was established, in part, with pulmonary function testing.

CASE REPORT

A 55-year-old man not awayed with a 5-year history of worsening dyspnea and associated dysphonia. His initial presentation of acute bitter choking and stridor was attributed to asthma, and symptoms resolv in days after therapy with inhaled bronchodilators. across the ensuing years, his symptoms were episodic and characterized mainly by stridor. Laryngeal polyps were noted during direct laryngoscopy 1 to 2 years later. Symptom oftenness and severity worsened 1 year prior to evaluation at our institution, at which time there was persistent dysphonia, hoarseness, and multiple daily episodes of the two inspiratory and expiratory limitation to breathing. His symptoms infrequently awoke him at night, were aggravated at emotional anxiety, and only mildly improved after therapy with low-dose lorazepam, taken 3 to 4 times a day.

The patient's medical history was significant for model II diabetes mellitus, hypertension, gastroesophageal ebb and obesity. A review of symptoms revealed no focal or generalized dystonias, change in balance, bowel, or bladder habits, or focal neurologic deficit.

The physical examination revealed the following: temperature, 372[degrees]C; BP 140/80 mm Hg; regular heart rate, 92 beats/min; and visible form [i]or[/i] frame mass index, 36.2. Tachypnea and stridorous respirations were noted with otherwise normal cardiovascular, upper and lower respiratory, and neurologic examinations. The consequence s of standard blood chemistry touchstones electrolyte measurements, urinalysis, thyroid-stimulating hormone measurement, and CT scans of the chest and neck were normal. Pulmonary function touchstones were ordered.

onward presentation to the pulmonary function laboratory, the patient's expiratory roll ons were mildly reduced during the FVC maneuver (FE[Vsub1] 282 L [78% predicted]; FVC 371 L [81% predicted]). Note that the FE[Vsub1] is reduc in proportion to the reduction in FVC implying a restrictive rather than an obstructive pattern. The maximal voluntary ventilation (MVV) was 43 L/min, which was strictly reduced (ie, 30% predicted) and was revealed of proportion to the FE[Vsub1] giving an MVV/FE[Vsub1] ratio of 15 (normal ratio, > 35) The diffusing capacity of the lung for carbon monoxide adjusted for hemoglobin (265) and oxygen saturation at peace and with exercise were normal.

The patient had difficulty performing reproducible maximal flow-volume bend s The best expiratory and inspiratory flow-volume maneuvers are shown in Figure 1 as well-as; not only-but also; not only-but; not alone-but loops are characterized by "notching" that is not attributable to cough In addition, the inspiratory loophole showed a plateau that was reproducible with repeat maneuvers. The mid-vital capacity value of the expiratory/inspiratory result ratio was > 2.

[FIGURE 1 OMITTED]

Airway resistance (Raw) studies were performed in a material part plethysmograph (1) using panting to create airway grow (Vaw) vs alveolar pressure (Palv) graph bights During normal panting maneuvers the Vaw v Palv graph revealed a dramatic plateau in the inspiratory issue (Fig 2). Raw, calculated in a linear region spanning naught flow, was significantly elevated and measured 188 em [Hsub2]O/ (405% predicted). Based forward these test findings, the diagnosis of a variable, extrathoracic, large-airway obstruction was made, and an otorhinolaryngology evaluation was obtained.

[FIGURE 2 OMITTED]

Evaluation via direct laryngoscopy revealed intermittent paradoxical motion of the vocal cords, that is, adduction of the cords during inspiration and early expiration (Fig 3 top). At peacefulness between inspiration and expiration, the two arytenoid cartilages and the supraglottic laryngeal arrangements spontaneously moved and completely occlud the glottis (Fig 3 bottom). Immediately after closure of the glottis, there was reopening, and then the proces was repeated.

[FIGURE 3 OMITTED]

As a outcome of these findings, and further neurologic evaluation, the diagnosis of idiopathic segmental dystonia, which is characterized by means of predominant laryngeal dysfunction and mild blepharospasm, was made. The patient was treated with botulinum toxin injection, 3 U into each thyroarytenoid muscle. The patient observ a certain number of mild relief of symptoms on the other hand required further injections 4 month later, again with a improvement but with no resolution of his symptoms.

DISCUSSION

VCD is a relatively exceptional disorder, but increasing numbers of publications have serv to better outline its incidence and natural history. Retrospective case series (23) have shown that VCD is diagnosed predominantly in women who are 30 to 50 years olden and who commonly have an increased visible form [i]or[/i] frame mass index and a history of psychiatric illness. As a be derived nonorganic and psychogenic causes have been propos as the predominant etiology of VCD However, a greater emphasis onward associated organic causes is now evolving and includes gastroesophageal ebb disease and neurologically based dystonias. Canine moulds (4) of gastroesophageal reflux disease have intimateed that a pH of [les than or equal to] 25 induces laryngeal spasm by the agency of vagally mediated mechanisms and the sensitization of mucosal chemoreceptors. It is hypothesized, therefore, that laryngeal hyperreponsiveness may be the underlying cause for VCD This state is deliberation to be induced by inflammatory insults and subsequently has been maintained from altered autonomic balance and repeated local stimuli. (5) In addition, neurologic dysfunction must be rul on the outside requiring specialty consultation. As this case illustrates, a thorough neurologic evaluation revealed an idiopathic segmental dystonia underlying this patient's symptomatology.

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