The paranasal sinuses in horses are air-filled cavities located within the skull, connected to the nasal passages. These sinuses include the frontal, maxillary, sphenopalatine, and ethmoid sinuses, among others. They are lined with a mucous membrane and play a role in respiratory health, contributing to the conditioning of inhaled air. The sinus system in horses is complex and can be affected by various conditions such as sinusitis, cysts, and tumors. This page compiles peer-reviewed research studies and scholarly articles that explore the anatomy, function, and clinical conditions associated with the paranasal sinuses in horses, providing insights into diagnostic approaches and treatment options in equine veterinary medicine.
Kutara K, Ono T, Hisaeda K, Inoue Y, Henmi C, Sho K, Ohnishi A, Ohzawa E, Une Y, Iwata E, Shibano K, Asanuma T, Kitagawa H.Noma horses have the smallest body size among native Japanese horses and are classified as pony breeds by their size. Additionally, the Japanese horse breeds are classified into a single lineage, which includes Mongolian horses. Great intraspecific differences reportedly exist in the head shapes of domesticated horses, which have been investigated in various horse breeds. The present study aimed to evaluate the size of the nasal conchal bullae, and the paranasal sinuses of Noma horses in relation to the skull dimensions using computed tomography. Reconstructed images of the heads of five adult...
Schwieder A, Pfarrer C, Ohnesorge B, Staszyk C, Bienert-Zeit A.Horses may acquire a range of paranasal sinus diseases. Clinical studies show slight differences regarding anatomical regions and age. Histopathological examination of tissue samples could play an important role in the diagnostic process. Therefore, detailed knowledge of the histological appearance of the paranasal sinus mucosa (PSM) and the nasomaxillary aperture mucosa (NAM) is essential. The objective of this study was to determine topographic and age-related differences within the healthy equine PSM. In addition, we aimed to gain detailed knowledge of the histological appearance of the NAM...
Ostrowska J, Lindström L, Tóth T, Hansson K, Uhlhorn M, Ley CJ.Computed tomography (CT) is commonly used to investigate equine paranasal sinus disease, however, only limited information is available in the literature about the detailed CT appearance of equine paranasal sinus cysts. Objective: To investigate if paranasal sinus cysts have specific characteristics in CT images that allow differentiation from other sinus diseases. Methods: Retrospective observational study. Methods: Evaluation and comparison of CT studies of eight horses with surgically and/or histopathologically confirmed paranasal sinus cysts and 10 horses with other confirmed paranasal sin...
Pouyet M, G Bonilla A.To describe the technique, experience, and limitations of using a 2-mm flexible endoscope to perform standing minimally invasive sinoscopy. Methods: In phases 1 and 2, we used cadaveric heads (ex vivo). In phase 3, we used unaffected horses (in vivo). Methods: Five cadaveric equine skulls in phase 1 and 10 cadaveric equine skulls in phase 2. Six horses older than 5 years in phase 3. Methods: In phase 1, the specimens were used to determine the suitability of the endoscope for sinoscopy and the ideal landmarks to approach the paranasal sinuses through minisinusotomies performed with a 14 gaug...
Fenner MF, Verwilghen D, Townsend N, Simhofer H, Schwarzer J, Zani DD, Bienert-Zeit A.Paranasal sinus cysts (PSC) are a common cause of equine secondary sinusitis. The outcome and associated complications have not been frequently reported. Objective: To review the associated clinical signs, associated morbidities and outcomes of horses treated for PSC. Methods: Retrospective multicentre case series. Methods: Retrospective analysis of case records and telephone follow up survey. Results: Subjects were 37 horses 1-24 years old that were presented with nasal discharge (n = 31), facial swelling (n = 25) and epiphora (n = 19). Radiography and computed tomography allowed identificati...
de Parades V, Bouchard D, Janier M, Berger A.Pilonidal disease is a frequent suppurative condition that occurs twice as often in men as in women, usually between the ages of 15 and 30. Pilonidal disease is located beneath the skin of the sacro-coccygeal region. It presents acutely as an abscess under tension while the chronic form gives rise to intermittent discharge from pilonidal sinus(es). Diagnosis is clinical and usually straightforward. In the large majority of cases, treatment is surgical but there is no consensus as to the 'ideal' technique. Acute abscess must be evacuated and an off-midline incision seems preferable. Excision is...
Textor JA, Puchalski SM, Affolter VK, MacDonald MH, Galuppo LD, Wisner ER.To determine whether CT provides unique information about the treatment or prognosis for horses with ethmoid hematoma (EH). Methods: Retrospective case series. Methods: 16 horses with EH. Methods: Horses with a diagnosis of EH that had undergone a diagnostic CT study were included. Clinical features, treatment, outcome, radiographic and CT images, and histologic specimens were reviewed. Results: CT provided new diagnostic information that affected treatment in 10 of 16 horses. Bilateral disease occurred in 8 of 16 horses and was undetected in 5 horses prior to CT. Paranasal sinus involvement o...
Waguespack RW, Taintor J.The paranasal sinus system of horses is complex, comprising six pairs of sinuses. Disease processes that can develop in the sinuses include ethmoid hematomas, cysts, neoplasia, and bacterial and fungal infections. Horses that develop paranasal sinus disease vary widely in age. A significant number of clinical conditions involving the paranasal sinuses require a combination of diagnostic tests to determine the specific pathologic process. Because of the anatomic location of the paranasal sinuses and associated chronic conditions that affect many patients, many disease processes involving the pa...
Barakzai S, Tremaine H, Dixon P.To describe and analyze subjective and objective scintigraphic findings in horses with paranasal sinus disorders. Methods: Horses with suspected disorders of the paranasal sinuses or cheek teeth (n = 48) and control horses (n = 30). Methods: 99Technetium-methylenediphosphate (99Tc-MDP; 7500 MBq) was administered for scintigraphic examination of the skull. Abnormal patterns of increased radionuclide uptake (IRU) were identified and subjectively described. Scintigrams and radiographs were blindly assessed by 2 clinicians and the accuracy of the imaging modalities was compared. Objective analysis...
Probst A, Henninger W, Willmann M.Heads from 15 male and female horses of various breeds and ages were examined with computed tomography under general anesthesia in dorsal recumbency. The main interest was the evaluation of the entire paranasal sinus system. Special attention was paid to the location, size, and shape of the conchomaxillary, nasomaxillary, frontomaxillary, and sphenopalatinal openings. The frontomaxillary opening was the largest aperture and was found to be age-dependent in size mostly. Orientation and shape of the openings were sagittal or horizontal; the narrowest of them was the slit-like nasomaxillary apert...
Walker MA, Schumacher J, Schmitz DG, McMullen WC, Ruoff WW, Crabill MR, Hawkins JF, Hogan PM, McClure SR, Vacek JR, Edwards JF, Helman RG, Frelier PF.Three adult horses underwent aggressive treatment of squamous cell carcinoma of the nasal cavity and paranasal sinuses, using course-fractionated cobalt 60 radiotherapy. Squamous cell carcinoma of the nasal cavity and paranasal sinuses is not commonly diagnosed in horses. Historically, horses with this type of neoplasm have not been treated or have undergone some form of surgery. The prognosis for long-term survival or cure has been poor. Long-term results of cobalt 60 radiotherapy were good to excellent and exceeded those usually reported for horses treated surgically. On the basis of these r...
Schumacher J, Honnas C, Smith B.Primary paranasal sinusitis complicated by inspissated exudate within the ventral conchal sinus was diagnosed in five horses. Clinical signs included a unilateral, foul-smelling, mucopurulent nasal exudate of 2 to 7 months' duration. Two of the horses had partial nasal obstruction from distortion of the ventral concha. Radiographs of the skull showed a mass of soft tissue density dorsal to the roots of the superior third and fourth or fourth and fifth cheek teeth. Treatment included bone flap maxillary sinusotomy with exposure of the ventral nasal concha and removal of inspissated exudate. Res...
Ostrowska J, Lindström L, Tóth T, Hansson K, Uhlhorn M, Ley CJ.Computed tomography (CT) is commonly used to investigate equine paranasal sinus disease, however, only limited information is available in the literature about the detailed CT appearance of equine paranasal sinus cysts. Objective: To investigate if paranasal sinus cysts have specific characteristics in CT images that allow differentiation from other sinus diseases. Methods: Retrospective observational study. Methods: Evaluation and comparison of CT studies of eight horses with surgically and/or histopathologically confirmed paranasal sinus cysts and 10 horses with other confirmed paranasal sin...
Schumacher J, Honnas C, Smith B.Primary paranasal sinusitis complicated by inspissated exudate within the ventral conchal sinus was diagnosed in five horses. Clinical signs included a unilateral, foul-smelling, mucopurulent nasal exudate of 2 to 7 months' duration. Two of the horses had partial nasal obstruction from distortion of the ventral concha. Radiographs of the skull showed a mass of soft tissue density dorsal to the roots of the superior third and fourth or fourth and fifth cheek teeth. Treatment included bone flap maxillary sinusotomy with exposure of the ventral nasal concha and removal of inspissated exudate. Res...
Textor JA, Puchalski SM, Affolter VK, MacDonald MH, Galuppo LD, Wisner ER.To determine whether CT provides unique information about the treatment or prognosis for horses with ethmoid hematoma (EH). Methods: Retrospective case series. Methods: 16 horses with EH. Methods: Horses with a diagnosis of EH that had undergone a diagnostic CT study were included. Clinical features, treatment, outcome, radiographic and CT images, and histologic specimens were reviewed. Results: CT provided new diagnostic information that affected treatment in 10 of 16 horses. Bilateral disease occurred in 8 of 16 horses and was undetected in 5 horses prior to CT. Paranasal sinus involvement o...
Barakzai S, Tremaine H, Dixon P.To describe and analyze subjective and objective scintigraphic findings in horses with paranasal sinus disorders. Methods: Horses with suspected disorders of the paranasal sinuses or cheek teeth (n = 48) and control horses (n = 30). Methods: 99Technetium-methylenediphosphate (99Tc-MDP; 7500 MBq) was administered for scintigraphic examination of the skull. Abnormal patterns of increased radionuclide uptake (IRU) were identified and subjectively described. Scintigrams and radiographs were blindly assessed by 2 clinicians and the accuracy of the imaging modalities was compared. Objective analysis...
Walker MA, Schumacher J, Schmitz DG, McMullen WC, Ruoff WW, Crabill MR, Hawkins JF, Hogan PM, McClure SR, Vacek JR, Edwards JF, Helman RG, Frelier PF.Three adult horses underwent aggressive treatment of squamous cell carcinoma of the nasal cavity and paranasal sinuses, using course-fractionated cobalt 60 radiotherapy. Squamous cell carcinoma of the nasal cavity and paranasal sinuses is not commonly diagnosed in horses. Historically, horses with this type of neoplasm have not been treated or have undergone some form of surgery. The prognosis for long-term survival or cure has been poor. Long-term results of cobalt 60 radiotherapy were good to excellent and exceeded those usually reported for horses treated surgically. On the basis of these r...
Pouyet M, G Bonilla A.To describe the technique, experience, and limitations of using a 2-mm flexible endoscope to perform standing minimally invasive sinoscopy. Methods: In phases 1 and 2, we used cadaveric heads (ex vivo). In phase 3, we used unaffected horses (in vivo). Methods: Five cadaveric equine skulls in phase 1 and 10 cadaveric equine skulls in phase 2. Six horses older than 5 years in phase 3. Methods: In phase 1, the specimens were used to determine the suitability of the endoscope for sinoscopy and the ideal landmarks to approach the paranasal sinuses through minisinusotomies performed with a 14 gaug...
Waguespack RW, Taintor J.The paranasal sinus system of horses is complex, comprising six pairs of sinuses. Disease processes that can develop in the sinuses include ethmoid hematomas, cysts, neoplasia, and bacterial and fungal infections. Horses that develop paranasal sinus disease vary widely in age. A significant number of clinical conditions involving the paranasal sinuses require a combination of diagnostic tests to determine the specific pathologic process. Because of the anatomic location of the paranasal sinuses and associated chronic conditions that affect many patients, many disease processes involving the pa...
Kutara K, Ono T, Hisaeda K, Inoue Y, Henmi C, Sho K, Ohnishi A, Ohzawa E, Une Y, Iwata E, Shibano K, Asanuma T, Kitagawa H.Noma horses have the smallest body size among native Japanese horses and are classified as pony breeds by their size. Additionally, the Japanese horse breeds are classified into a single lineage, which includes Mongolian horses. Great intraspecific differences reportedly exist in the head shapes of domesticated horses, which have been investigated in various horse breeds. The present study aimed to evaluate the size of the nasal conchal bullae, and the paranasal sinuses of Noma horses in relation to the skull dimensions using computed tomography. Reconstructed images of the heads of five adult...
Probst A, Henninger W, Willmann M.Heads from 15 male and female horses of various breeds and ages were examined with computed tomography under general anesthesia in dorsal recumbency. The main interest was the evaluation of the entire paranasal sinus system. Special attention was paid to the location, size, and shape of the conchomaxillary, nasomaxillary, frontomaxillary, and sphenopalatinal openings. The frontomaxillary opening was the largest aperture and was found to be age-dependent in size mostly. Orientation and shape of the openings were sagittal or horizontal; the narrowest of them was the slit-like nasomaxillary apert...
Schwieder A, Pfarrer C, Ohnesorge B, Staszyk C, Bienert-Zeit A.Horses may acquire a range of paranasal sinus diseases. Clinical studies show slight differences regarding anatomical regions and age. Histopathological examination of tissue samples could play an important role in the diagnostic process. Therefore, detailed knowledge of the histological appearance of the paranasal sinus mucosa (PSM) and the nasomaxillary aperture mucosa (NAM) is essential. The objective of this study was to determine topographic and age-related differences within the healthy equine PSM. In addition, we aimed to gain detailed knowledge of the histological appearance of the NAM...
Fenner MF, Verwilghen D, Townsend N, Simhofer H, Schwarzer J, Zani DD, Bienert-Zeit A.Paranasal sinus cysts (PSC) are a common cause of equine secondary sinusitis. The outcome and associated complications have not been frequently reported. Objective: To review the associated clinical signs, associated morbidities and outcomes of horses treated for PSC. Methods: Retrospective multicentre case series. Methods: Retrospective analysis of case records and telephone follow up survey. Results: Subjects were 37 horses 1-24 years old that were presented with nasal discharge (n = 31), facial swelling (n = 25) and epiphora (n = 19). Radiography and computed tomography allowed identificati...
de Parades V, Bouchard D, Janier M, Berger A.Pilonidal disease is a frequent suppurative condition that occurs twice as often in men as in women, usually between the ages of 15 and 30. Pilonidal disease is located beneath the skin of the sacro-coccygeal region. It presents acutely as an abscess under tension while the chronic form gives rise to intermittent discharge from pilonidal sinus(es). Diagnosis is clinical and usually straightforward. In the large majority of cases, treatment is surgical but there is no consensus as to the 'ideal' technique. Acute abscess must be evacuated and an off-midline incision seems preferable. Excision is...
