Pseudocyst of the auricle: diagnosis and management with a punch biopsy

A case of pseudocyst of the ear diagnosed and treated with a punch biopsy is reported. Pseudocyst of the ear is considered to be a benign, asymptomatic condition seen infrequently in clinical practice. Our patient is a 45-year-old white man who presented with a 5-month history of a painless nodule on his left auricle without any preceding history of trauma. Although many treatments have been reported, none appear satisfactory, and many surgical treatment modalities are cumbersome. This is the first report, to our knowledge, of a case of a pseudocyst of the ear confirmed and treated with a 3-mm punch biopsy of the inferior border of the pseudocyst, followed by a pressure bolster.

Natural history of severe decompression sickness after rapid ascent from air saturation in a porcine model

We developed a swine model to describe the untreated natural history of severe decompression sickness (DCS) after direct ascent from saturation conditions. In a recompression chamber, neutered male Yorkshire swine were pressurized to a predetermined depth from 50-150 feet of seawater [fsw; 2.52-5.55 atmospheres absolute (ATA)]. After 22 h, they returned to the surface (1 ATA) at 30 fsw/min (0.91 ATA/min) without decompression stops and were observed. Depth was the primary predictor of DCS incidence (R = 0.52, P < 0.0001) and death (R = 0.54, P < 0.0001). Severe DCS, defined as neurological or cardiopulmonary impairment, occurred in 78 of 128 animals, and 42 of 51 animals with cardiopulmonary DCS died within 1 h after surfacing. Within 24 h, 29 of 30 survivors with neurological DCS completely resolved their deficits without intervention. Pretrial Monte Carlo analysis decreased subject requirement without sacrificing power. This model provides a useful platform for investigating the pathophysiology of severe DCS and testing therapeutic interventions. The results raise important questions about present models of human responses to similar decompressive insults.

Cutaneous lesions in swine after decompression: histopathology and ultrastructure

A detailed histopathologic description of skin lesions from a porcine model of decompression sickness (DCS) is presented. Pigs were dived in a dry chamber on a variety of profiles over an 11-mo period, with a 0.1-0.6 (10-60%) incidence of cutaneous lesions. The clinical appearance of the lesions evolved from irregular, sharply demarcated areas of erythema to violaceous and, eventually, darkly mottled macules. The lesions were biopsied under deep, sedative anesthesia. Histologic abnormalities were found in 91% (20/22) of the biopsies from clinically apparent cutaneous lesions. Vascular congestion was the most common finding. Focal areas of vasculitis were noted in 45% (10/22) of the lesions. Perivascular neutrophil infiltrates, edema, and occasionally, hemorrhage were also noted. Ultrastructural abnormalities were found in all of the lesions studied. Acute inflammation affecting the dermal vasculature was the most common finding. Platelets were rarely observed aggregating within vessels. The clinical and histologic features of cutaneous lesions in pigs after decompression are compared with previous accounts in humans. The model provides a useful tool for the study of cutaneous lesions in DCS and may be a means of exploring interventions in the disease.