Crackles are the clicking, rattling, or crackling noises that may be made by one or both lungs of a human with a respiratory disease during inhalation. They are usually heard only with a stethoscope ("on auscultation"). Pulmonary crackles are abnormal breath sounds that were formerly referred to as rales.Bilateral crackles refers to the presence of crackles in both lungs. Basal crackles are crackles apparently originating in or near the base of the lung. Bibasal crackles refer to crackles at the bases of both the left and right lungs. Bilateral basal crackles also refers to the presence of basal crackles in both lungs. Crackles are caused by the "popping open" of small airways and alveoli collapsed by fluid, exudate, or lack of aeration during expiration. Crackles can be heard in patients with pneumonia, atelectasis, pulmonary fibrosis, acute bronchitis, bronchiectasis, acute respiratory distress syndrome (ARDS), interstitial lung disease or post thoracotomy or metastasis ablation. Pulmonary edema secondary to left-sided congestive heart failure can also cause crackles. Terminology
René Laennec adopted the existing word râles (which has been translated as "rattles", groans" and otherwise) to describe the added breath sounds that are now referred to as "crackles".
While virtually all cases of NF and variants have had excellent prognoses, the two cases of individuals with an USP6-PPP6R3 fusion gene in their NF tumor cells had less favorable prognoses: their tumors were locally invasive, repeatedly relapsed after surgical removal, and grew progressively larger over 2 and 10 years of observations. Treatment
Some cases of NF have regressed after being partially biopsied suggesting that a watchful waiting approach may be appropriate after biopsy in some cases of these tumors. In all events, the most common and generally accepted first-line treatment for most cases of NF, craniofacial fasciitis, and intravascular fasciitis tumors is surgical removal. In almost all cases this removal is curative, i.e. tumor recurrences are uncommon, even in cases where the tumor is only partially removed. Furthermore, tumor recurrences are typically cured by simple re-excisions. NF cases have also been successfully treated with corticosteroid drugs (e.g. triamcinolone) injected directly into the tumor; this treatment has been most often used for patients with recurrent tumors. Some studies, however, have suggested reevaluating the diagnosis in recurrent NF tumors to ensure the diagnosis is correct. Surgical and corticosteroid interventions may need to be performed promptly in order to avoid expansion of a cranial tumor into the skulls interior or an intravascular fasciitis tumor from compromising blood flood flow. Prognosis
Two cases of NF in which their tumor cells expressed a USP6-PPP6R3 fusion gene had highly aggressive, locally invasive, repeatedly recurrent (after surgical removal), and progressively enlarging tumors over 2 and ten years. One case developed multiple metastases (i.e.