[An unusual cause of sinusitis]. / Een ongewone oorzaak van sinusitis.

BACKGROUND: Larvae of the sheep botfly (Oestrus ovis) normally have sheep or goats as host. In humans the larvae can survive for a short time in the nose or under the eyelids, after which they die or are sneezed out. CASE DESCRIPTION: We describe a 47-year-old woman who during a stay in the Cape Verde Islands developed symptoms of sneezing, a swollen face and an itchy feeling in her nose. These symptoms were due to an infestation of three fully-developed larvae of the O. ovis species in her sinus maxillaries which were later evacuated by endoscopy. CONCLUSION: In exceptional cases larvae of the O. ovis species can fully mature in a healthy person after a visit to an endemic area. Development into the mature stage has only been described in patients with a poor mucosal immune response.

Intrinsic and extrinsic forces determine the distortion of the split cricoid ring.

OBJECTIVE: An anterior cricoid split (ACS) causes an immediate distortion of the cricoid cartilage resulting in an anterior gap due to retraction of the cut ends. The objective of this animal study is to investigate: (1) to what extent the distortion after ACS is influenced by non-cartilaginous structures like tunica elastica, membranes, ligaments and muscles, which are connected to the cricoid; (2) how distortion is changing with further development; (3) in what way the distortion is affected by scoring of the internal surface of the cricoid; and (4) whether an immediate or late injury-induced distortion is related to age. METHODS: Surgical interventions were performed in 20 young (8 weeks of age, 1300-1600 g) and 5 adult (28 weeks of age, 3500-4000 g) New Zealand White rabbits. The immediate effects were measured, and then the animals were followed for 20 weeks to study the long-term effects of the various procedures. RESULTS: (1) The gap, immediately following an ACS, increased after additional transection of the cricothyroid ligament and the cricotracheal membrane, and even more when the cricovocal membrane was elevated from the inner surface of the cricoid arch. (2) The degree of distortion after various interventions in young animals appeared to increase substantially during further growth. (3) When the above-mentioned successive surgical steps were combined with scoring of the internal surface of the cricoid arch, a marked malformation of the split cricoid did develop with warping of the cut ends in lateral direction and a latero-cephalic rotation, the latter due to the action of the cricothyroid muscles. (4) The immediate distortion appeared to be similar in young and adult animals. During a follow-up of 20 weeks, a progressive distortion of the split cricoid ring was observed in the young growing rabbits. In adult animals, no significant progression of the distortion was found. CONCLUSIONS: The immediate and long-term distortion of the split cricoid is determined by the release of intrinsic forces of the cartilage, and extrinsic forces from non-cartilaginous structures like ligaments, muscles, membranes and tunica elastica.

Controlling incision-induced distortion of nasal septal cartilage: a model to predict the effect of scoring of rabbit septa.

Cartilage can be shaped by scoring. In an exploratory study in living adult animals, this phenomenon was demonstrated in cartilage of the nasal septum. Bending was observed immediately after superficial scoring of the cartilage surface, and the cartilage always warped in the direction away from the scored side. The scored piece of cartilage still showed its initially distorted shape 10 weeks after primary surgery. In ex vivo experiments, a clear relation between incision depth and bending of septal cartilage was observed. Under these controlled conditions, the variation between different septa was small. Deformation of the septal specimens was increased by introducing single superficial incisions deepening to half the thickness of the cartilage. A positive correlation between incision depth and bending was demonstrated. A model was used to accurately predict the degree of bending of the cartilage after making an incision of a particular depth. Hence, the effect of cartilage scoring can be predicted. Because the results of this controlled study showed excellent reproducibility for different septa, it is expected that this model can be extrapolated to human nasal septum cartilage. This would enable the surgeon to better predict the result of cartilage scoring, either preoperatively or perioperatively.