Effect of internal maxillary arterial occlusion on nasal blood flow in swine.

OBJECTIVES: The precise effects of therapeutic occlusion of the internal maxillary artery (IMA) on distal nasal mucosal perfusion are unknown. A better understanding of these effects has important implications regarding the rationale and expected efficacy of certain therapeutic interventions for epistaxis management. The authors developed an animal model to assess these issues. STUDY DESIGN: The effects of "proximal" and progressively more "distal" occlusions of the IMA on nasal mucosal blood flow (NBF) were assessed in anesthetized swine using continuous laser Doppler flowmetry. The levels of arterial occlusion were selected to simulate clinical therapeutic occlusions used for the management of epistaxis. METHODS: Nineteen swine were entered into one of four experimental groupings: proximal IMA occlusion using platinum micro-coils (n = 6), mid-grade distal IMA occlusion with polyvinyl alcohol particulate (PVA) suspensions (300 to 500 microns, n = 5), high-grade distal IMA occlusion with polyvinyl alcohol particulate suspensions (50 to 150 microns, n = 5), and sham control (n = 2). RESULTS: All embolizations resulted in acute decreases in average NBF from 120 mL/min per 100 g to 40 mL/min per 100 g (P < .05 for all groups). NBF returned to baseline in all three treated groups within 2 to 8 days after therapeutic embolization, depending on the level of occlusion (coils, 2 d; mid-grade PVA, 2-3 d; high-grade PVA, 8 d). Follow-up angiography showed recanalization and collateralization as possible methods of reestablishing NBF. CONCLUSIONS: This study supports the rationale for performing distal IMA occlusion with transarterial particulate embolization, in order to provide a longer period of time of diminished NBF. This theoretically should promote hemostasis within an injured portion of the nasal mucosa by decreasing perfusion pressure within the capillary bed. However, the benefits of distal IMA embolization must be balanced against potential ischemic complications, as may be more commonly seen with high-grade particulate embolization.

Intrapancreatic ciliated enteric duplication cyst presenting with biliary obstruction.

A 46-yr-old man presenting with biliary obstruction from an intrapancreatic tumor underwent pancreaticoduodenectomy. The pathology report showed the tumor to be an enteric duplication cyst. Diagnostic imaging features and operative management are discussed.

True malignant mixed tumor (carcinosarcoma) of tonsillar minor salivary gland origin: diagnostic imaging and endovascular therapeutic embolization.

We report a case of carcinosarcoma of the minor salivary glands of the left palatine tonsil, an especially rare location. Imaging characteristics assessed at CT, MR imaging, and angiography are presented. In addition, we describe our experience with preoperative therapeutic endovascular embolization of this hypervascular tumor.

Occult spontaneous lateral temporal meningoencephalocele: MR findings of a rare developmental anomaly.

We describe a case of an occult lateral temporal meningoencephalocele discovered in a 14-year-old boy during a work-up for minor head trauma. This spontaneous encephalocele resulted from a closure defect at the former sphenoidal fontanelle. Preoperative MR images are presented.

Large haemangiopericytoma of the posterior cervical space. The role of imaging and therapeutic embolisation in the management of an unsuspected hypervascular head and neck neoplasm.

SUMMARY: We report a case of a 39-year old woman who upon developing a rapidly enlarging posterior cervical space tumour, underwent incisional biopsy prior to diagnostic imaging that resulted in nearly catastrophic haemorrhage. Subsequently, MR imaging showed evidence of marked hypervascularity, prompting diagnostic angiography and endovascular microembolization prior to surgical resection. The tumour turned out to be a large haemangiopericytoma arising from the paravertebral musculature. The case is instructive by highlighting the need for considering rare locations of hypervascular tumours in the head and neck region before attempting biopsy, which can be predicted by cross-sectional imaging studies, and the benefits of pre-operative devascularization with modern superselective microembolisation techniques.