Ethmoid Hematoma versus Paranasal Sinus Cyst in a Horse

Two horses presented to PHD Veterinary services for the same complaint of "no air moving through one of the horse's nasal passages!" Both horses had a history of mild to moderate nasal discharge that had increased slowly over the past 6 months. On presentation, a simple evaluation of air passing through the nasal cavities revealed that there was NO air moving through the affected side on each horse however, endoscopic exam revealed a unique problem in each horse.

Figure 1

 In Figure 1, a smooth, white soft tissue mass was identified within 2 inches of the opening of the nasal cavity. This soft tissue mass was completely obstructing the nasal passage. In addition, when the scope was passed through the unaffected side, the soft tissue mass was noted to be extending into the naso-pharynx suggesting that the soft tissue mass extended through out the entire nasal passage (Figure 2). In Figure 2, the white wall of tissue noted along the right side of the image is the soft tissue mass as it extends into the naso-pharynx.The soft tissue mass is most likely consistent with a paranasal sinus cyst however surgical removal will be required to confirm the diagnosis. These types of cysts develop in young horses and grow slowly over months and years until a clinical problem develops. Surgical removal provides complete resolution of these types of cysts!!

Figure 2

Figure 3

In the second horse, a large golden-colored soft tissue mass was identified in the region of the nasal passage closest to the naso-pharynx. There was more discharge associated with this soft tissue mass and small areas of hemorrhage were noted. The soft tissue mass was completely obstructing the nasal passage and was originating from the ethmoid turbinate region which most likely classified it as a ethmoid hematoma!! These types of tumors typically present with a complaint of a unilateral bloody nasal discharge for months before they completely obstruct the nasal passage. However, they can be fast growing tumors and require an aggressive approach to eradicate. Treatment may involve either surgical removal or repeated injections of formalin. It has been my experience, having injected several horses for YEARS, that the tumors tend to return with this approach! Hence, I recommend surgical removal when first diagnosed, especially if the tumor is invading the sinus cavity or the naso-pharynx.

IIeal Hypertrophy in a Horse

A 10 year old Paso fino mare presented for recurrent colic for several months duration. The mare had a long history of being a "hard keeper" but in the past 3-4 months had begun to colic after each feeding. The mare was fed a diet of senior feed plus free-choice coastal bermuda grass hay. The mare was referred to PHD Veterinary services for a gastroscopy (stomach scope). The mare presented with a body condition score of 3 out of 9. The client reported that the mare had a good appetite yet shortly after eating, the mare would develop signs consistent with abdominal discomfort! The gastroscopy was normal therefore we opted to ultrasound the mare's abdomen.  In Figure 1 there is a cross-sectional image of a loop of intestine (black circle) that is grossly abnormal. The lumen (center) is completely filled in with soft tissue(grey area). The filled in center in Figure 1 corresponds to thickening of the small intestine which likely results in delayed passage of ingesta. Interestingly, there was only 1 very distinct area of the small intestine that scanned abnormally thick. However, there were several loops of small intestine that were dilated and had diminished peristalsis (Large black circles in Figure 2).

Figure 1

Figure 2

The ultrasound findings were consistent with a focal area of thickened small intestine and a large area of dilated small intestine. The dilated small intestine were likely "up stream" from the thickened small intestine and were as a result of partial obstruction of the thickened small intestine. Based on these findings, the mare was referred for abdominal exploratory surgery. During the abdominal exploration, a very thick region of the small intestine was identified. This region corresponded to the ileum which is the very final section of the small intestine. Approximately 12 inches of ileum were grossly thickened resulting in minimal lumen formation for passage of ingesta (Figure 3). Normally, the ileum is a wide-open tube as depicted in Figure 4!! Unfortunately, due to the severity of the condition, poor prognosis, and financial limitations, the mare was euthanized on the surgical table. Ileal hypertrophy has been reported in horses consuming coastal bermuda grass hay and it is theorized that some horses develop an "allergic" response to coastal hay resulting inflammation of the ileum and ultimately gross thickening. More commonly, colic symptoms associated with coastal hay is due to poor quality hay rather than ileal hypertrophy. However, any horse with chronic colic symptoms that is consuming coastal bermuda grass hay should be evaluated for this condition. 

Figure3

Figure4

Extensor Process Fracture in a Horse

A teen-age gelding presnted for the complaint of forelimb lameness. The gelding had been purchased approximately 6 months prior and the prepurchase exam performed did NOT include a radiographic exam. The gelding was mildly lame in a straight line however the lameness was significantly worse when lunged in a small circle. Through a series of nerve blocks it was determined that the lameness was originating from the foot and a radiographic study was performed. The radiographic images in Figure 1-3 are lateral views of the foot in question. Two abnormalities are noted by the yellow and blue arrows in Figure 2. The blue arrow corresponds to a chip fracture of the extensor process of the coffin bone and the yellow lines correspond to extensive mineralization of the cartilage of the foot (side bone).

Figure 1

Figure 2

 In Figure 3, the extensor process chip fracture is magnified. It is likely that this chip fracture was present at the time of purchase and would have been discovered had the client opted for a radiographic exam of the forelimb feet.  In my opinion, this radiographic finding would have been reason enough the FAIL the horse at the time of prepurchase exam.  In addition to the extensor chip fracture, moderate "side bone" development is evident in the lateral view and the dorsal-palmar view (Figure 4). Typically, side-bone does not present a clinical problem however does consist of an abnormal finding and in this horse the side bone is more pronounced along the inside versus the outside of the foot. The asymmetry of the side-bone may be more clinically relevant that bilateral side-bone that is symmetrical.

Figure 3

Figure 4

The horse was treated with intra-articular corticosteroid and is approximately 75% improved with respect to lameness. The long term prognosis for this horse is guarded due to fracture of the extensor process of the coffin bone. This case represents yet another example of the need for at least foot radiographs at the time of prepurchase exam.

Fractured Coffin Bone in a Horse

The radiographic images below are from a horse that presented for a 2 week history of non-weight bearing lameness in a forelimb. The horse had been treated for a suspect abscess with minimal clinical improvement. Interestingly, the horse was minimally responsive to hoof tester exam.

Figure 1

In the lateral radiograph (Figure 1) there is no obvious explanation for the lameness. However in the subsequent radiographs (Figures 2-4) the cause for the lameness is evident. A large fracture of the coffin bone is apparent. The fracture extends from the toe region all the way through the joint!

Figure 2

 In Figures 3 and 4, the fracture line appears to encompass the entire length of the coffin bone. The prognosis for future soundness depends on whether the fracture communicates with the coffin joint. If it does, the prognosis for soundness is poor due to the likelihood of developing of advanced osteoarthritis. This type of fracture will eventually heal with the correct shoeing and adequate rest. However, the prognosis for return to soundness is guarded due to the severity of this fracture!

Figure 3

Figure 4