Echocardiography of the normal bovine heart: technique and ultrasonographic appearance

Fifty-one clinically healthy cows were examined ultrasonographically from the third and fourth intercostal spaces on both sides of the thorax. A 3.0 MHz transducer was used and the heart was examined in the caudal long, caudal short and cranial long axes on the right side, and in the caudal and cranial long axes on the left side. In each position the optimal transducer orientation and the images of the structures were recorded. In the caudal long axis view of the heart on the right (transducer positioned at the fourth intercostal space), all four chambers were visible with the transducer positioned 8 to 10 cm dorsal to the level of the olecranon. The left ventricular outflow tract, consisting of the aortic valve and ascending aorta, were visible in the same position with the transducer rotated 10 to 40 degrees clockwise. In the caudal short axis view of the heart on the right, the left and right ventricles were visible in cross-section with the transducer held at right angles to the ribs in the fourth intercostal space, 3 to 6 cm dorsal to the olecranon and tipped slightly dorsally. In the cranial long axis view of the heart on the right, the right ventricular outflow tract, consisting of the pulmonary valve and pulmonary artery, was visible in the third intercostal space, 8 to 10 cm dorsal to the olecranon with the transducer angled craniodorsally and rotated 10 to 20 degrees clockwise. In the caudal long axis view of the heart on the left, the left and right ventricles and the left ventricular outflow tract were visible with the transducer placed in the fourth intercostal space. In the cranial long axis view on the left, the right ventricular outflow tract was visible.     

Equine thoracoscopy: normal anatomy and surgical technique

Six normal, healthy horses age 3-10 years underwent left and right thoracoscopic examination using a rigid telescope. A minimum of 30 days was allowed between procedures. Horses were restrained in stocks and sedated with a continuous detomidine infusion. After surgical preparation of the hemithorax elected for surgery, and administration of local or regional anaesthesia of the surgery sites, thoracoscopy was completed during two 15 min pneumothorax periods. During the procedures, the thoracic structures were viewed using a 57 cm, 10 mm diameter, 30 degrees rigid telescope connected to a digital camcorder to allow computer capture of digital images. The telescope was inserted into the thoracic cavity via 3 different intercostal spaces. The 8th, 10th and 12th intercostal spaces were randomly selected and used among horses. The exploration of each hemithorax started from the dorsal-caudal quadrant continued toward the cranial thorax and was completed by observing the diaphragmatic and caudal pulmonary region. Collapsed lung, aorta, oesophagus and diaphragm were viewed readily in either hemithorax. On exploration of the right hemithorax, the azygos vein, thoracic duct and pulmonary veins were also identified. Horses tolerated thoracoscopy well. Signs of discomfort, such as increased respiratory rate, coughing and decreased level of sedation, were associated with lung collapse in one horse, with pneumothorax on 2 occasions, and when the thorax was approached through the 8th intercostal space. Surgery performed via the 8th intercostal space was hindered by the rigidity of the 8th and 9th ribs, and by the presence of a greater musculature, which did not allow easy cranial and caudal movements of the telescope.     

Ultrasonographic findings in cows with right displacement of the abomasum and abomasal volvulus

Seventeen cows with right displacement of the abomasum (rda) without abomasal volvulus, nine cows with abomasal volvulus and 10 clinically healthy cows were examined ultrasonographically. A 5.0 MHz transducer was used to scan the eighth to 12th intercostal spaces and the cranial and caudal aspects of the flank on the right side. The position, size and dorsal and ventral margins of the abomasum were determined at each imaging position. In both groups of diseased cows, the ventral abomasum contained fluid ingesta, which appeared hypoechogenic with diffuse echogenic stippling. The abomasal folds could be seen clearly as echogenic sickle-shaped structures within the ingesta. The dorsal abomasal gas cap varied in size and was characterised by reverberation artefacts, which appeared as echogenic lines running parallel to the body surface. Compared with the healthy cows, the abomasum was larger and located significantly closer to the midline of the dorsum in both groups of cows. Compared with the cows with rda, the abomasum in the cows with abomasal volvulus was significantly smaller in the eighth intercostal space and significantly larger in the 11th intercostal space. It was not possible to differentiate between rda and abomasal volvulus on the basis of the ultrasonographic findings.     

Ultrasonographic characteristics of abdominal and thoracic abscesses in cattle and buffaloes

Six cows and five buffaloes with abdominal and thoracic abscesses were examined clinically and ultrasonographically. There was a wide range of clinical signs and at least 50% of the animals exhibited dull demeanour, anorexia, abdominal pain, recurrent tympany and/or weight loss. Three cases of abdominal abscesses were imaged in the left ventral abdomen between the rumen and abdominal wall, two cases were imaged at the xiphoid cartilage near the reticular wall and one case was imaged on the right ventral abdomen between the jejunum and right abdominal wall. Four cases of thoracic abscesses were imaged in the third intercostal space on the left side; however, one case of abscess was imaged in the fourth intercostal space, also on the left side. The content of the abscess was echogenic in eight animals and anechoic in three. In three animals, the content of the abscess was partitioned by echogenic septae. In two cows, the echogenic content of the abscess was surrounded by a narrow rim of anechoic fluid. The diameters of the abscesses were 5-10 cm in three cows, 11-15 cm in seven cows and >15 cm in one cow. In every case, the diagnosis was confirmed by centesis and aspiration of the abscess, which yielded purulent material. There were biochemical data of hypoalbuminaemia and hyperglobulinaemia and 90% of tested animals had neutrophilia. Five cows were examined at slaughter, where the ultrasonographic diagnosis was confirmed.     

Ultrasonographic examination of the spleen in 30 goats

The ultrasonographic appearance, location and size of the spleen in 30 healthy female Saanen goats are described. The intercostal spaces of the left thoracic wall were scanned with a 5.0 MHz linear transducer in standing goats. The appearance of the splenic parenchyma, the position of the ultrasonographically visible dorsal and ventral margins of the spleen and the distance between them, the thickness of the spleen and the diameter of the splenic vessels were determined. The spleen could be visualised in at least one examination position and it always lay between the rumen and abdominal wall. The spleen bordered the lung dorsally and was located adjacent to the left abdominal wall in the last intercostal space and area immediately caudal to the last rib. The spleen had an echogenic capsule, and its parenchyma showed a homogenous fine echotexture / echo pattern throughout the whole visible part of the spleen. The splenic vessels were seen within the parenchyma. The visible dorsal margin of the spleen ran from cranioventral to caudodorsal. The distance from the dorsal margin of the spleen to the midline of the back was greatest in the 8th intercostal space (19.7 ± 4.19 cm) and smallest in the region immediately caudal to the last rib (7.0 ± 1.07 cm). The size of the spleen was smallest in the 8th intercostal space (3.1 ± 1.24 cm) and greatest in the 11th intercostal space (8.7 ± 2.78 cm). The thickness of the spleen ranged from 2.2 ± 1.14 cm caudal to the last rib to 6.4 ± 1.78 cm in the 11th intercostal space.     

Transabdominal ultrasonographic appearance of the gastrointestinal viscera of healthy camels (Camelus dromedaries)

The purpose of this study was to describe the ultrasonographic picture of the gastrointestinal tract in healthy camels (Camelus dromedarius). For this purpose, 22 camels were examined. The rumen and its glandular sacs were filling most of the left side of the abdomen. The rumen wall was smooth and echogenic. The ventral part of the reticulum could be best imaged in 17 (77%) camels from the left and right paramedian region just behind to the sternal pad. The reticulum in these animals had a thick wall (1.17±0.27 cm) that appeared as a half-moon-shaped structure with a biphasic contraction. The omasum was best viewed through the right 8th to 6th intercostal spaces in 18 (82%) camels. In the remaining 4 (18%), it was visualized through four consecutive intercostal spaces (right 9th to 6th). It had a wall thickness of 1.1±0.7 cm and a transverse diameter of 8.74±3.4 cm. The abomasum could be best visualized from the right 9th and 8th intercostal spaces in 14 (64%) camels, while it was observed in the 9th intercostal space in 3 (14%) animals and in the 8th and 7th intercostal space in 5 (22%) camels. Small intestinal structures were best seen low in the right paralumbar fossa. It was thin-walled (0.43±0.14 cm) and had a diameter of 2.62±0.47 cm. The cecum was imaged chiefly in the caudal right flank. It was thin-walled (0.37±0.05 cm), had a diameter of 13.8±1.6 cm. The proximal loop of the large colon appeared as thick, echogenic, continuous and slightly curved lines. It was thin-walled (0.51±0.08 cm) and had a diameter of 3.5±0.8 cm. The spiral colon was confined in all camels to the caudal ventral half of the abdomen. It appeared as structures with thick echoic lateral walls with a number of echogenic arched lines next to each other. Free peritoneal fluid pockets were imaged in two locations in 19 (86%) camels. Ultrasound-guided abdominocentesis was successful in 15 (68%) of the examined camels. This study provides the ultrasonographic appearance of the normal gastrointestinal tract in healthy camels that could be used as a reference for the interpretation of suspected digestive abnormalities.     

Ultrasonography of the rumen in 30 Saanen goats

This study describes the results of ultrasonographic examination of the rumen in 30 healthy Saanen goats. A linear or convex transducer with a variable frequency of 5 to 13 MHz was used to scan standing, non-sedated goats. The location and size of the rumen, the distance between the wall of the rumen and abdominal wall and the appearance and size of the gas, fibre mat and fluid layers of the ruminal contents were assessed. The rumen was seen as a large organ medial to the left abdominal wall. The wall of the rumen appeared as a thick echogenic line. The longitudinal groove was seen as an echogenic notch, which divided the rumen into the dorsal and ventral sacs. The rumen could be visualized from the 9th to 12th intercostal space (ICS) and flank on the left side in all the goats. The rumen was largest in the 12th ICS at 41.6 ± 5.13 cm and smallest in the 8th ICS at 11.3 ± 4.29 cm. The dorsal sac of the rumen was largest in the left cranial flank (17.4 ± 4.43 cm) and the ventral sac was largest in the 12th ICS on the left (29.1 ± 6.03 cm). In the cranial left flank, the rumen was situated immediately adjacent to the abdominal wall in all the goats. The spleen was located between the rumen and abdominal wall in the 8th to 12 th ICS in many of the goats. The gas, fibre mat and fluid layers of the ruminal contents could be visualized in all the goats. The gas layer was 9.9 ± 3.05 cm, the fibre mat layer 16.0 ± 4.55 cm and the fluid layer 12.2 ± 5.57 cm.     

Sonographic examinations of the intestines in calves

The aim of this investigation was to describe the normal ultrasonic appearance of the intestinal loops of calves at different stages of their adolescence and at various intervals after suckling and to determine reliable reference values. Therefore the abdomen of 20 clinically healthy calves have been examined with a 5 MHz sector probe on the right and left flank of each animal and the exact position, the largest diameter, the thickness of the walls, the peristaltic activity and the appearance of the contents of each part of the intestines described. Most often, the pars cranialis duodeni could be seen ventral of the right costal arch as well as in the right flank, with younger calves it also showed in the left flank sometimes. The position could be changed considerably depending on the period elapsed since the last suckling time.The duodenum descendens and the duodenum ascendens could be traced in the right flank. The thickness of the wall was found to measure between 2 and 3 mm throughout the whole duodenum. The examination of the jejunum and the ileum was basically done in the right flank. In cases where the rumen was not yet fully developed visualization was also possible in the left flank. Most often these parts were seen in cross-section displaying permanent peristaltic activity. With the younger calves the large intestine could equally be traced in both flanks. In older animals it could be recognized as voluminous hollow organ filled with gas, or in case of the colon ascendens as garlandshape. In the jejunum and ileum as well as in the large intestine the thickness of the wall measured between 1 and 2 mm. Each part of the intestine showed an increase in diameter as the calves grew older. The peristaltic activity increased during two hours after suckling and during this time the echoing level of the contents was lower.     

Lateral abdominal hernia associated with thin abdominal musculature in a calf

This study aimed to evaluate the clinical utility of ultrasonography in the diagnosis of a newborn calf presenting with extended swelling within its right flank, in addition to its therapeutic planning. Ultrasonograms of the bilateral flanks identified thinning of the external and internal oblique abdominal muscles in whole areas of the abdominal walls. A right lateral abdominal hernia associated with thin abdominal muscular structures was diagnosed ultrasonographically. The right flank abdominal hernia was successfully reconstructed through a modified Mayo mattress suture. This allowed the overlapping of the two very thin structures of the abdominal walls, resulting in the creation of a thicker structure of the right lateral abdominal walls. Reconstruction of the abdominal walls using this method could prevent re-protrusion of the viscera during calf growth.     

Ultrasonography of the urinary tract in 29 female Saanen goats

The left and right kidneys, ureters, urinary bladder and urethra of 29 female clinically healthy Saanen goats were examined via transcutaneous and transrectal ultrasonography. In order to establish reference values the examinations were performed using a 5.0 MHz linear transducer to scan the right caudal costal part of the abdominal wall, right and left dorsal flanks and right and left inguinal regions of standing goats. A 5.0 MHz intracavity probe was used for transrectal ultrasonographic examination of the urinary bladder and urethra. The kidneys were examined in longitudinal and cross section and assessed subjectively. They could usually be seen from the 12th intercostal space on the right side and dorsal right flank. The right kidney was 8.0 ± 0.67 cm long and the left was 8.4 ± 0.64 cm long. The ureters could not be visualized in any of the goats. The length of the urinary bladder was 5.1 ± 1.38 cm, and its largest cross-sectional diameter was 2.6 ± 1.01 cm. The urethra was seen in 23 goats and appeared as echogenic lines with no visible lumen. The transition from the neck of the bladder to the internal urethral orifice extended beyond the brim of the pelvis in only one goat.     

Examination of the thoracic cavity and lung lobectomy by means of thoracoscopy in dogs.

The feasibility of thoracoscopy for viewing the chest cavity and performing pulmonary lobectomy was assessed in 8 mongrel dogs. Previously, selective intubation had been performed in another group of dogs (n = 8) in order to monitor respiratory physiology and assess its safety. Each hemithorax was intubated using a double-barrelled endotracheal tube with one barrel placed in the left main bronchus and the other in the bifurcation of the trachea. The thoracoscope was introduced through a cannula inserted through a 2-cm incision at the ventral third of the left 5th intercostal space. The cranial, dorsal, and caudal surfaces of the pleura, lobes of the left lung, and the mediastinum were examined. A 2nd cannula was located in the dorsal 3rd of the 5th intercostal space with a prior incision and used for the introduction of forceps to separate the viscera. To biopsy, a 3rd cannula was inserted at the dorsal third of the 8th intercostal space with a prior incision, through which a 12-mm diameter stapler was introduced. Should a lobectomy be necessary, a 4th cannula is located in the middle third of the 4th intercostal space. Excision of the left caudal pulmonary lobe was performed through the incision made for the 12-mm diameter cannula (8th intercostal space); a twisting movement facilitated removal. Thoracoscopy is a procedure that can be used in dogs and is particularly suitable for examination, collection of biopsy specimens, and even lung lobectomies.     

Renal carcinoma in a horse

A poorly performing nine-year-old thoroughbred mare was presented because of chronic weight loss. On rectal examination an abdominal mass was palpated and, on percussion of the right flank from the 11th to 13th intercostal space, a large area of dullness was delineated. Biopsies taken from the liver region and through the rectum revealed a malignant metastasising tumour of the urinary system. After euthanasia, the post mortem findings confirmed the presence of a papillary renal carcinoma with multiple metastases into the omentum and peritoneum.     

Gastrointestinal ultrasonography in normal adult ponies

The objective of this study was to determine the characteristics based on ultrasonographic examination of the stomach, duodenum, jejunum, cecum, and peritoneal fluid in normal adult ponies. Abdominal ultrasonographic examination was performed in nine unsedated standing ponies. The duodenum was examined at three sites and the jejunum in 12 regions. Wall thickness, contractility, distention, and luminal contents were recorded. Stomach wall thickness and location, cecal wall thickness, and peritoneal fluid location and character were recorded. Statistical analysis was performed. Wall thicknesses (in cm) were 0.431 +/- 0.069 for the stomach, 0.188 +/- 0.033 for the duodenum (at all sites), 0.195 +/- 0.031 for the jejunum (at all regions), and 0.179 +/- 0.031 for the cecum. Duodenal contractions per minute were 3.78 +/- 1.10. The stomach spanned 5.14 +/- 0.9 intercostal spaces, with the 8th intercostal space being the most cranial and the 15th intercostal space being the most caudal space through which the stomach was identified. It was possible to identify the jejunum in all ponies dorsal to the left dorsal colon and from the ventral abdominal wall. Peritoneal fluid was identified in six ponies. Peritoneal fluid was usually seen transiently and most commonly in the ventral aspect of the abdominal cavity or around the duodenum. Overall, the ponie's abdominal ultrasonographic examinations revealed wall thicknesses that were less than the published normal ranges for horses. It appears that ponies may have increased duodenal contractility than horses and that the conformation of ponies may change the locations for imaging the stomach.     

ULTRASONIC EXAMINATION OF THE PANCREAS IN HEALTHY COWS

The purpose of this study was to describe the ultrasonographic appearance of the normal bovine pancreas and to establish reference values for healthy cattle. Ultrasonographic examinations were performed on the right side of 20 healthy cows. Ultrasonographically the body and right limb of pancreas appeared as a triangle-shaped structure associated with the liver, portal vein, right kidney, and duodenum. In comparison to normal liver, the pancreas appeared isoechoic or slightly more echogenic. The right lobe of the pancreas was evaluated from the right flank to the eleventh intercostal space, and the body of the pancreas was visualized from the twelfth to the tenth intercostal space. The left lobe of the pancreas could not be seen because of its dorsomedial location. In 9 cows, the accessory pancreatic duct was located near the right lobe of the pancreas and appeared as two parallel echogenic lines with a hypoechogenic area between them. The diameter of the accessory pancreatic duct varied from 6 to 8 mm. The pancreaticoduodenal vein was seen in 5 cows. The diameter of the pancreaticoduodenal vein varied from 3 to 4 mm. The ultrasonographic characteristics determined in this study may serve as a reference in the evaluation of cows with suspected pancreatic disease.     

Ultrasonographic examination of the omasum in 30 healthy cows

A 3.5 MHz linear transducer was used to scan the intercostal spaces of 30 healthy cows from dorsal to ventral on the right side, and the appearance, dorsal and ventral limits and size of the omasum were determined in each intercostal space. The size of the omasum determined ultrasonographically was compared with that determined postmortem. The distance between the omasum and the peritoneum of the lateral body wall was also determined electronically in each intercostal space by means of the two cursors. In the sixth to 11th intercostal spaces, the omasum had a crescent shape, with only the wall closest to the transducer visible as a thick echogenic line. The dorsal limit of the omasum appeared from cranial to caudal as the upper part of a circle, whereas the ventral omasal limit appeared as the lower part of a circle. The mean (sd) size of the omasum varied with the intercostal spaces from 16.3 (1.5) cm to 56.9 (10.0) cm; it was greatest in the ninth intercostal space and decreased cranially and caudally. The omasum was closest to the right abdominal wall in the eighth and ninth intercostal spaces, and was immediately adjacent to these spaces in 22 and 20 cows, respectively. There were significant correlations between the size of the omasum determined ultrasonographically in the ninth intercostal space and the weight, volume and largest and smallest diameters of the omasum determined postmortem, with correlation coefficients (r) between 0.38 and 0.55.     

Arthroscopy of the Coxofemoral Joint of Foals

An arthroscopic procedure for examination of the coxofemoral joint was developed in nine foals (four cadavers, five anesthetized) to determine if access was sufficient for evaluation and surgical treatment of intra-articular lesions. The joint was distended and the arthroscope inserted through the notch (incisura trochanterica) between the cranial and caudal parts of the greater trochanter. This portal allowed examination of the cranial, lateral, and caudal aspects of the joint. Mechanical distraction of the joint through an instrument portal located 2 to 4 cm cranial and 1 to 2 cm ventral to the arthroscope portal allowed examination of the ligament of the head of the femur, the femoral head, and articular and nonarticular surfaces of the acetabulum. Adduction and rotation of the limb improved visualization of the craniomedial and caudomedial portions of the femoral head. Traction applied to the distal limb allowed visualization of the same structures that were observed when mechanical distraction was used. Traction also created space for placement of surgical instruments into the joint through the instrument portal. Access to most regions of the joint was adequate, but access to the caudal and medial aspects of the joint was limited. Three foals were killed while they were anesthetized, and their coxofemoral joints were dissected. Two foals were allowed to recover from anesthesia and were observed for 30 days after surgery. One foal was mildly lame for 2 days after surgery. The other foal was not lame after surgery. The incisions healed, and the coxofemoral joints were radiographically normal by postoperative day 30.     

Laparoscopic Anatomy of the Llama Abdomen

Paralumbar laparoscopy was performed, caudal to the last rib, in seven llamas. All animals were anesthetized, instrumented, and placed in sternal recumbency. Systematic exploration was performed in six donated llamas dividing the abdomen into right and left, cranial and caudal quadrants. The main structures of diagnostic significance that could be observed from the right side were the parietal and visceral surface of the liver, diaphragm, first compartment of the stomach (CI), caudal aspect of the third compartment of the stomach (C3), pancreas, kidney duodenum, jejunum, and ascending colon. From the left side CI, varying lengths of jejunum, ileum, ascending colon, and spiral colon were identified. From both approaches the bladder, and in females the uterus and ovaries could be observed. All animals were necropsied immediately following the procedure. Gross examination of the abdominal viscera in the did not yield any abnormalities that had been missed by laparoscopic evaluation. Using a left paralumbar approach, one clinical case presenting with signs of acute abdominal discomfort was evaluated. A diagnosis was made of diffuse enteritis that was confirmed at necropsy. Because of the distensible nature of the South American camelid (SAC) abdominal wall, the small size of the abdominal viscera, and the freely mobile nature of most portions of the gastrointestinal tract a thorough examination was possible in all animals.     

Diagnostic and prognostic indicators of omasal impaction in buffaloes (Bubalus bubalis)

Twelve of 46 female buffaloes with abdominal disorders were diagnosed with omasal impaction. They had been fed finely chopped machine-prepared straw. They were characterised by anorexia, an absence of defecation, abdominal distension, ruminal hypomotility or atony and a suspension of rumination. Omasal impaction was confirmed upon left flank laparorumenotomy on the basis of the size of the omasum and the consistency of its contents. After ruminal evacuation, a long flexible pipe was introduced through the reticulo-omasal orifice and the omasal contents were flushed back into the rumen with water under moderate pressure. Hyponatraemia, hypochloraemia, hypokalaemia and hypophosphataemia were consistent features in most cases. However, two buffaloes that later died had lower levels of plasma chloride, no reticulo-omasal orifice tone and were in an advanced stage of pregnancy. The level of total protein in peritoneal fluid was higher than normal, but the total white cell count was within the normal range. All the animals started passing faeces 36 to 48 hours after surgery. The presence of reticulo-omasal orifice tone and a plasma chloride level above 75 mmol/l were indicators of a good prognosis.