Case Description—A 5-month-old 1.9-kg (4.2-lb) spayed female Siamese cat was evaluated because of a history of decreased appetite, regurgitation, vomiting, and lack of weight gain.
Clinical Findings—Radiographic findings included a fluid- and gas-distended stomach with a small accumulation of mineral opacities. Ultrasonographic examination confirmed severe fluid distention of the stomach with multiple hyperechoic structures present and revealed protrusion of the thickened pylorus into the gastric lumen, with normal pylorogastric serosal continuity. Endoscopy of the upper gastrointestinal tract revealed an abnormally shortened pyloric antrum and stenotic pyloric outflow orifice. Pyloric stenosis resulting in pyloric outflow obstruction was diagnosed.
Treatment and Outcome—A pylorectomy with end-to-end gastroduodenostomy (Billroth I procedure) was successfully performed, and a temporary gastrostomy tube was placed. Six days after surgery, the cat was eating and drinking normally, with the tube only used for administration of medications. The gastrostomy tube was removed 12 days after surgery. Results of follow-up examination by the referring veterinarian 3 weeks after surgery were normal. Occasional vomiting approximately 2 months after surgery was managed medically. Fifteen months after surgery, the owners reported that the cat seemed completely normal in appearance and behavior.
Clinical Relevance—Pyloric stenosis should be considered a differential diagnosis for young cats with pyloric outflow obstruction. The cat of this report was treated successfully with a Billroth I procedure. Histologic examination and immunohistochemical analysis of the excised tissue showed the stenosis to be associated with hypertrophy of the tunica muscularis.
OBJECTIVE To determine brain region affinity for and retention of gadolinium in dogs after administration of gadodiamide and whether formalin fixation affects quantification.
ANIMALS 14 healthy dogs.
PROCEDURES 13 dogs received gadodiamide (range, 0.006 to 0.1 mmol/kg, IV); 1 control dog received a placebo. Dogs received gadodiamide 3 to 7 days (n = 8) or 9 hours (5) before euthanasia and sample collection. Brain regions were analyzed with inductively coupled mass spectrometry (ICP-MS) and transmission electron microscopy. Associations between dose, time to euthanasia, and gadolinium retention quantities (before and after fixation in 5 dogs) were evaluated.
RESULTS Gadolinium retention was seen in all brain regions at all doses, except for the control dog. Exposure 3 to 7 days before euthanasia resulted in 1.7 to 162.5 ng of gadolinium/g of brain tissue (dose-dependent effect), with cerebellum, parietal lobe, and brainstem affinity. Exposure 9 hours before euthanasia resulted in 67.3 to 1,216.4 ng of gadolinium/g of brain tissue without dose dependency. Transmission electron microscopy revealed gadolinium in examined tissues. Fixation did not affect quantification in samples immersed for up to 69 days.
CONCLUSIONS AND CLINICAL RELEVANCE Gadodiamide exposure resulted in gadolinium retention in the brain of healthy dogs. Cerebellum, parietal lobe, and brainstem affinity was detected with dose dependency only in dogs exposed 3 to 7 days before euthanasia. Fixation had no effect on quantification when tissues were immersed for up to 69 days. Physiologic mechanisms for gadolinium retention remained unclear. The importance of gadolinium retention requires further investigation.