Evaluation of the Cranial Rectus Abdominus Muscle Pedicle Flap as a Blood Supply for the Caudal Superficial Epigastric Skin Flap in Dogs

This study evaluates the cranial rectus abdominus muscle pedicle flap as the sole blood supply for the caudal superficial epigastric skin flap. This flap was composed of a cranially based rectus abdominus muscle pedicle flap that was attached to the caudal superficial epigastric island skin flap (including mammary glands 2 to 5) via the pudendoepigastric trunk. Selective angiography of the cranial epigastric artery in eight cadaver dogs proved that the arterial vasculature in the cranial rectus abdominus was contiguous with that in the caudal superficial epigastric skin flap. In the live dog study, three of six of the flaps failed because of venous insufficiency. Necrosis of mammary gland 2 occurred in two of six flaps. One of six flaps survived with the exception of the cranial most aspect of mammary gland 2. Angiography of the cranial epigastric artery proved that arterial blood supply to these flaps was intact. Histological evaluation of the failed flaps showed full-thickness necrosis of the skin and subcutaneous tissues, the presence of severe congestion, and venous thrombosis. Retrograde venous blood flow through the flap was inconsistent, and hence resulted in failure of this myocutaneous flap. Use of this flap for clinical wound reconstruction cannot be recommended.     

Direct cutaneous arterial supply to the tail in dogs.

Cutaneous arterial blood supply to the tail was evaluated in 12 dogs. Subtraction radiography of internal iliac artery and distal aorta angiography in 3 of these dogs was used to determine arterial blood supply to the tail from the median sacral and lateral caudal arteries. Dissection of the tail in 8 canine cadavers revealed bilateral subcutaneous location of lateral caudal arteries following tail amputation. An axial pattern flap based on the lateral caudal arteries contributed to the reconstruction of a large caudodorsal cutaneous defect in a dog. An axial pattern flap based on the lateral caudal arteries following tail amputation may be indicated to aid reconstruction of large caudodorsal cutaneous defects of the trunk in dogs.     

The arterial supply of the eye of the yak (Bos Grunniens)

The heads and necks of 10 yaks were dissected to study the arterial supply to the eye of the yak in the Qinghai-Tibetan Plateau. The supply came from the internal ophthalmic, external eight ophthalmic, superficial temporal and malar arteries. The internal ophthalmic was one of sources of the posterior long ciliary artery. The external ophthalmic artery gave rise to branches to supply the dorsal oblique muscle and otherwise, and to take part in the formation of the ophthalmic rete mirabile. The ophthalmic rete mirabile gave off many branches to supply the rectus muscles of the eye and otherwise. The malar artery was one of the branches derived from the infraorbital artery, and its branches supplied the inferior, superior and third eyelids and otherwise. The superficial temporal artery detached off some branches to supply the lateral angle of the eye and otherwise, and anastomosed with the lacrimal artery of the ophthalmic rete mirabile.     

The Anatomic Basis for a Trapezius Muscle Flap in Dogs

The anatomy of the cervical part of the trapezius muscle and its dominant vascular supply, the prescapular branch of the superficial cervical artery, was studied by dissection and selective angiography of 16 canine cadavers. The prescapular branch of the superficial cervical artery supplies blood to the skin of the caudal half of the neck and the cervical part of the trapezius muscle and is a minor contributor to other muscles of the neck. In these dogs, the mean length of the vascular pedicles was 4.4 cm and the mean diameter was 1.0 mm. With this information, it is possible to design a broad musculocutaneous flap suitable for reconstructive microsurgery in dogs. The potential for successful incorporation of the scapular spine in such a flap remains uncertain.     

Die Arterien der Articulatio coxae und des proximalen Femurabschnittes bei der Katze (Felis catus)*

The arterial blood supply of the hip joint and the proximal end of the femur was studied grossly and microscopically in 40 cats. The aim of the study was to provide clinicians with an overview of the arterial supply to the area. The findings were discussed and compared with those in dogs reported in the literature.     

Brow suspension for treatment of ptosis and entropion in dogs with redundant facial skin folds

Brow suspension surgery was performed on 7 dogs with redundant facial skin folds, associated ptosis, and entropion. The surgical technique involved subcutaneous placement of polyester mesh strips to suspend the upper eyelid from the dorsal frontalis muscle and the underlying periosteum of the skull. Visual impairment associated with ptosis was resolved in all dogs at the 2 week reevaluation period. Upper eyelid position was maintained in 4 of 7 dogs available for long-term follow-up. One dog developed persistent draining tracts in the region of the implant, and removal of part of the implanted mesh was eventually required. Upper eyelid height in this dog, however, was maintained following mesh removal, probably because of fibrosis around the implant. Brow suspension is an option for surgical management of upper eyelid ptosis and entropion in dogs with redundant skin folds and avoids the need for facial skin fold excision.     

Macroanatomic investigations of the blood supply of thoracic limb of Kangal dogs

In this study, the arterial supply of the thoracic limb was investigated in Kangal dogs. Twelve adult healthy Kangal dogs of either sex were used. Latex was injected into the common carotid artery, and then the axillary artery was dissected. The axillary artery is a continuation of the subclavian artery and supplies the thoracic limb in Kangal dogs. The axillary artery gave off a deltoid branch and external thoracic, lateral thoracic, and subscapular thoracic arteries in its course along the thoracic wall. The axillary artery continues distally as the brachial artery in the arm. The brachial artery gives rise to the cranial humeral circumflex, deep brachial, bicipital, ulnar collateral, superficial brachial, transverse cubital, and common interosseus arteries. It continues as the median artery after giving off the common interosseus artery. It was observed that the deep antebrachial artery arose from the median artery at the proximal third of the forearm. In the distal third of the forearm, the median artery divided into the palmar carpal and dorsal carpal branches. The deep palmar branch of the radial artery and deep branch of the palmar branch of the caudal interosseus artery form the deep palmar arch. The median artery joined the superficial branch of the palmar branch of the caudal interosseus artery to constitute the superficial palmar arch. The radial artery and cranial interosseus artery contributed to the dorsal carpal rete. The ulnar artery contributed to the formation of the deep and superficial palmar arches.     

Rapid Tissue Expansion for the Development of Rotational Skin Flaps in the Distal Portion of the Hindlimb of Dogs: An Experimental Study

In phase I, tissue expanders were implanted subcutaneously over the lateral crural region of four dogs. The expanders were inflated daily to maintain a constant intraluminal pressure for 7 days. All animals tolerated the pressurized expanders well. Some animal patient discomfort was associated with repeated injections into the subcutaneous filling port. One dog developed a limited area of tissue loss and exposure of the expander. Tissue response to the expanders included epidermal hyperplasia, dermal collagen compression with early fibroplasia, and subcutaneous granulation tissue formation adjacent to the expander pocket. In phase II, a second group of four dogs underwent rapid skin expansion over 7 days. The pressure applied to the expanding skin was determined daily and adjusted to approximate the value reported for capillary pressure in the dog. Tissue discoloration occurred in two dogs, suggestive of impaired circulation. Skin flaps were developed from expanded skin and rotated over the talocrural region. Wound dehiscence occurred along the distal flap margin in three phase II dogs. These wounds healed by second intention. Branches of the caudal saphenous artery were identified, using angiography, as the primary blood supply to the skin flaps.     

The Intraosseous Blood Supply of the Canine Radius: Implications for Healing of Distal Fractures in Small Dogs

The intraosseous vascular anatomy of the radius was studied in 12 pairs of canine cadaver limbs. Six pairs of specimens were obtained from small-breed dogs (less than 6 kg) and six pairs were obtained from large-breed dogs (18 to 30 kg). All specimens were studied after arterial injection with India ink. Samples were fixed, frozen, then sectioned and processed using a modified Spalteholz technique. In all specimens, the intraosseous blood supply arose from the nutrient artery with its associated branches and the metaphyseal arteries. In small-breed dogs, there was decreased vascular density at the distal diaphyseal-metaphyseal junction compared with large-breed dogs. The reduced vascularity corresponded to the region associated with a poor prognosis for fracture healing in small-breed dogs. This regional association suggests that a decreased vascular supply in the distal radius may contribute to a higher frequency of delayed union and nonunion in smaller dogs.     

Caudal Superficial Epigastric Arterial Pedicle Grafts in the Dog

A direct cutaneous arterial pedicle graft (axial pattern flap) was created from the mammary chain including glands 2 through 5 using the caudal superficial epigastric artery and vein in 4 male and 4 female dogs. All grafts survived immediate development and transfer to the recipient site which was either the flank, inner thigh, or lower limb region. A high per cent survivability rate can be expected if precautions are taken. This procedure has special application for reconstruction of extensive flank, inner thigh and inguinal skin losses.     

Axial Pattern Flap Based on the Superficial Temporal Artery in Cats: An Experimental Study

Objective — The purpose of this study was to determine the surgical guidelines for and the survivability of an axial pattern flap based on the superficial temporal artery in cats.
Study Design — The mean survival length and mean percentage area of survival of flaps after 7 days in control and experimental groups, are assessed and compared.
Animals — Ten mature, domestic shorthair cats.
Methods — The superficial temporal artery and vein were incorporated in the flaps of the experimental group (n = 5) and were ligated in the control group (n = 5). Seven days postoperatively, the length of tissue that remained viable in each flap was determined by measurement of the length of the grossly devitalized tissue and subtracting this from total flap length. Results — Mean width and length of all flaps was 2.0 ± 7.0 cm, respectively. Mean survival length (±SD) of experimental and control flaps was 6.9 (0.2) cm and 4.4 (2.2) cm, respectively. Necrosis occurred in all control flaps, resulting in a mean percentage area of survival of 62.8 (11.7)%, compared with 98.6 (3.2)% for experimental flaps. Results were significantly different (P <.05) between the experimental and control groups.
Conclusions — A flap based on the superficial temporal artery may be a source of skin for reconstructive procedures of the maxillofacial region in cats.
Clinical Relevance — Knowledge of the anatomic landmarks and survivability of an axial pattern flap are essential considerations when planning a reconstructive technique.     

Evaluation of the Doppler ultrasonic method of measuring systolic arterial blood pressure in cats.

The accuracy of the Doppler technique for indirect systolic blood pressure measurement was assessed in 16 anesthetized cats. Eight cats were anesthetized with isoflurane and 8 were anesthetized with halothane. Anesthetic depth and mode of ventilation were varied to obtain a wide range of arterial blood pressure. A Doppler transducer was placed on the palmer surface of the left forelimb over the common digital branch of the radial artery to detect blood flow, and a blood pressure monitoring cuff with a width 37% the limb circumference was placed half way between the elbow and the carpus. To enable direct arterial pressure measurements, the left femoral artery was catheterized and the blood pressure waveforms recorded simultaneously. Systolic blood pressure measured by use of the Doppler ultrasonic technique was significantly lower than that obtained from the femoral artery catheter. Using linear regression, we determined a clinically useful calibration adjustment for Doppler indirect blood pressure measurement in cats: femoral systolic pressure = Doppler systolic pressure + 14 mm of Hg.     

The Macroscopic Vascular Anatomy of the Equine Ethmoidal Area

The vascular anatomy of the ethmoidal area in six normal horses and two normal ponies was studied using vascularcorrosion casts. The major arterial supply to the ethmoidal area sterns from an intracranial source. The internal and external ethmoidal arteries anastomose on the rostral intracranial surface of the cribriform plate to form the arterial ethmoidal rete which arborizes and passes through the perforations of the cribriform plate to supply the ethmoid labyrinth. A minor arterial supply to the ventral portion of the ethmoid labyrinth sterns from a small caudal nasal branch of the sphenopalatine artery. Multiple parallel venules drain the ethmoid labyrinth rostrally to its apex then join the venous drainage from the surrounding sinuses.     

Caudal Sartorius Muscle Flap in the Dog

An anatomic study was performed on canine cadavers to define the blood supply to the caudal sartorius muscle. The vascular supply to this muscle was segmental with the saphenous artery and vein providing a distal vascular pedicle. Anastomotic channels existed between distal and proximal capillary beds within the muscle belly. This anatomic information was used to determine the feasibility of performing caudal sartorius muscle flaps in dogs. The caudal sartorius muscle was transposed to the medial tibial region in four dogs. The muscle flap was based on a singular vascular pedicle of the saphenous artery and vein. The muscle transpositions were all successful on day 14 as evidenced by gross appearance and results of histologic examination. Grossly, the muscles were well adhered to the recipient sites and were covered by connective tissue. Histologically, the specimens were characterized by viable skeletal muscle fibers, large amounts of granulation tissue, varying degrees of inflammatory response, and small foci of myocyte necrosis (2 cases). Seroma formation was a consistent postoperative complication.     

Evaluation of an oscillometric blood pressure monitor for use in anesthetized cats

OBJECTIVE: To determine accuracy of an oscillometric blood pressure monitor used over a wide range of pressures in anesthetized cats. DESIGN: Prospective study. ANIMALS: 6 healthy cats. PROCEDURE: 4 female cats and 2 male cats that weighed 2.7 to 4.5 kg (5.9 to 9.9 lb) and were 2 to 8 years old were anesthetized. Blood pressure was measured directly with an arterial catheter placed in the right femoral artery and indirectly from the left antebrachium by use of an oscillometric monitor. A series of diastolic arterial pressure (DAP), mean arterial pressure (MAP), and systolic arterial pressure (SAP) measurements were obtained during hypotension, normotension, and hypertension. Values obtained indirectly and directly were compared. RESULTS: The oscillometric monitor was accurate for DAP and MAP throughout the entire pressure range and met the standards of the Association for the Advancement of Medical Instrumentation (mean +/- SD difference from values obtained directly, < or = 5 +/- 8 mm Hg). The SAP was increasingly underestimated with increasing overall pressure; mean differences from direct measurements were -5.2, -12.1, and -17.7 mm Hg during hypo-, normo-, and hypertension, respectively. Standard deviations for SAP were all < or = 8 mm Hg. The monitor gave readings during all attempts. The direct blood pressure recording system appeared to perform well with neither under- nor overdamping. CONCLUSIONS AND CLINICAL RELEVANCE: Except for a minor underestimation of SAP during normo- and hypertension, the oscillometric monitor yielded reliable and easily obtainable blood pressure measurements in anesthetized cats.     

Correlation between fine-needle aspiration cytology and histopathology in the evaluation of cutaneous and subcutaneous masses from dogs and cats

BACKGROUND: Fine-needle aspiration cytology (FNAC) is commonly used as a diagnostic procedure to evaluate superficial and deep masses in animals. However, few studies have addressed the accuracy of FNAC in the evaluation of cutaneous and subcutaneous masses in a clinical setting. OBJECTIVE: The purpose of this study was to compare the accuracy of FNAC as compared with histopathology in the diagnosis of cutaneous and subcutaneous masses from dogs and cats. METHODS: Cytologic and histopathologic specimens obtained between 1999 and 2003 from 292 palpable cutaneous and subcutaneous masses obtained from 242 dogs and 50 cats were retrospectively evaluated. Cytologic samples were obtained by FNA and histopathologic samples were collected by surgical biopsy or at necropsy. Concordance was determined and the accuracy of FNAC for the diagnosis of neoplasia was determined using histopathology as the gold standard. RESULTS: Of 292 specimens, 49 (from 44 dogs and 5 cats) were excluded due to poor cellularity of the cytologic specimen (retrieval rate 83.2%, n = 243). A cytologic diagnosis of neoplasia was obtained in 176 cases (175 true positives and 1 false positive compared with histopathology). Sixty-seven cytology samples were classified as non-neoplastic (46 true negatives, 21 false negatives compared with histopathology). Overall, the cytologic diagnosis was in agreement with the histopathologic diagnosis in 90.9% (221/243) of cases. For diagnosing neoplasia, cytology had a sensitivity of 89.3%, a specificity of 97.9%, a positive predictive value of 99.4%, and a negative predictive value of 68.7%. CONCLUSIONS: The results of this study confirmed FNAC as a reliable and useful diagnostic procedure for the evaluation of palpable cutaneous and subcutaneous lesions in small animal practice.     

Evaluation of the utility and accuracy of body fluids containing red blood cells to determine canine and feline blood types

Objective

To examine the accuracy of using body fluids macroscopically suspected to contain erythrocytes to determine the blood type in dogs and cats by use of an immunochromatographic cartridge (ICC), compared to systemic blood as the reference standard.

Design

Prospective study.

Setting

University teaching hospital.

Animals

Thirty client-owned dogs and 8 cats.

Interventions

Dogs and cats with a sanguineous or serosanguineous body fluid (SBF) that also required a blood sample were eligible for inclusion. PCV and blood type were determined in all blood and fluid samples. For body fluids with a low PCV and discordant blood type results compared to systemic blood, sample concentration and repeat blood typing from the fluid was performed when enough sample was available.

Measurement and Main Results

Body fluid samples consisted of 16 pleural (11 dogs; 5 cats), 12 peritoneal (10 dogs; 2 cats), and 4 canine pericardial effusions, 3 urine samples, and 1 each of feces and epistaxis from dogs and a seroma sample from a cat. Median (range) manual PCV of blood and fluid samples was 34% (14%–66%) and 6% (0.5%–70%) for dogs and 28% (14%–48%) and 14% (0.5%–19%) for cats, respectively. Dogs were correctly classified as being DEA 1 negative, DEA 1 positive, and DEA 1 weak positive when using body fluid for blood typing 13 of 14, 4 of 9, and 5 of 7, respectively. All reference blood type to fluid blood type (FBT) discordant results had a body fluid PCV equal to or below 2%. Subsequently concentrated body fluid samples had a PCV above 8% and repeat FBT matched reference blood type (RBT). All cats were classified as type A by all RBTs and FBTs.

Conclusions

Body fluids containing erythrocytes may be utilized to blood type dogs if sufficiently concentrated and type A cats.     

Cranial Sartorius Muscle Flap in the Dog

An anatomic study was performed on canine cadavers to define the blood supply to the cranial sartorius muscle. The vascular supply to this muscle was found to be a single dominant pedicle branching from the femoral artery at the proximal portion of the muscle. This anatomic information was applied in designing a study to determine the feasibility of performing a cranial sartorius muscle flap in the dog. The cranial sartorius muscle was transposed to the caudal abdominal region in four dogs. The muscle flap was based on the singular vascular pedicle defined in the anatomic study. All muscle transpositions were successful on day 19 as evidenced by gross appearance and histologic examination. Grossly, the muscles were well adhered to the recipient sites and were covered by connective tissue. Histologically, the specimens were characterized by viable skeletal muscle fibers, proliferative and maturing granulation and fibrous connective tissue, and mild to moderate mononuclear inflammation. Seroma formation and infection were the two postoperative complications noted. The cranial sartorius muscle flap has potential clinical application for repair of traumatic caudal abdominal hernias and large inguinal hernias in the dog.     

Anatomic and radiologic observations of the clavicle of adult dogs

In an anatomic and radiologic study of the clavicle of 50 adult dogs of 10 breeds, the clavicle had ossified in 96% of the dogs. The clavicles studied had various shapes, and each clavicle was attached to the caudomedial part of the clavicular intersection of the brachiocephalic muscle, to the mastoid part of the cleidocephalic muscle, and to 4 radiating bands of connective tissue fasciculi. One band was attached to the caudal border of the scapula and fascia deep to the latissimus dorsi muscle, 1 was attached to the manubrium of the sternum, and 1 each was attached to the epimysia of the superficial pectoral and sternocephalic muscles. We concluded that, during movements of the thoracic limb, the clavicle and the 4 fasciculated connective tissue bands associated with it stabilize the position of the brachiocephalic muscle with relation to the crest of the greater tubercle of the humerus. Also, the fasciculated band attached to the caudal border of the scapula provides protection for nerves from the brachial plexus and axillary blood vessels that supply the thoracic limb.