Cavity Of Dogs Research Articles

Outcome of accelerated radiotherapy alone or accelerated radiotherapy followed by exenteration of the nasal cavity in dogs with intranasal neoplasia: 53 cases (1990–2002)

To compare long-term results of radiotherapy alone versus radiotherapy followed by exenteration of the nasal cavity in dogs with malignant intranasal neoplasia. Retrospective study. 53 dogs with malignant intranasal neoplasia. All dogs underwent radiotherapy consisting of administration of 10 fractions of 4.2 Gy each on consecutive weekdays. For dogs in the surgery group (n=13), follow-up computed tomography was performed, and dogs were scheduled for surgery if persistent or recurrent tumor was seen. Perioperative complications for dogs that underwent surgery included hemorrhage requiring transfusion (2 dogs) and subcutaneous emphysema (8). Rhinitis and osteomyelitis-osteonecrosis occurred significantly more frequently in dogs in the radiotherapy and surgery group (9 and 4 dogs, respectively) than in dogs in the radiotherapy-only group (4 and 3 dogs, respectively). Two- and 3-year survival rates were 44% and 24%, respectively, for dogs in the radiotherapy group and 69% and 58%, respectively, for dogs in the surgery group. Overall median survival time for dogs in the radiotherapy and surgery group (477 months) was significantly longer than time for dogs in the radiotherapy-only group (19.7 months). Results suggest that exenteration of the nasal cavity significantly prolongs survival time in dogs with intranasal neoplasia that have undergone radiotherapy. Exenteration after radiotherapy may increase the risk of chronic complications.

Lipossarcoma em cão: relato de dois casos

This work aims to describe the clinical and anatomopathological findings of two cases of liposarcoma diagnosed in the subcutaneous and abdominal cavity of dogs. In both cases, the tumoral masses were surgically removed and samples were submitted for histopathological analyses. Microscopic examination of each case revealed a highly cellular, pleomorphic neoplasm with round or polygonal fat cells. The nuclei was elongate or splindle-shape (subcutaneous liposarcoma) and round or ovoid (abdominal liposarcoma), contained margined chromatin, and prominent nucleolus. Cytoplasmic vacuoles that stained positively with Sudan IV varied highly in size.

Efficacy of cobalt-60 radiation therapy for the treatment of nasal cavity nonkeratinizing squamous cell carcinoma in the dog.

The purposes of this study were to evaluate the efficacy of cobalt-60 radiotherapy in the treatment of nonkeratinizing squamous cell carcinoma of the nasal cavity in dogs and to compare this treatment group to historical controls. Six dogs with histopathologically confirmed nasal cavity nonkeratinizing squamous cell carcinoma were treated with cobalt-60 radiotherapy to a total dose of either 63 Gy or 54 Gy. Overall survival times ranged from 30 days to 330 days, with a median survival time of 165 days. Nasal cavity nonkeratinizing squamous cell carcinoma in the dog is an aggressive tumor that responds poorly to radiotherapy.

Preclinical evaluation of a novel device for delivering brachytherapy to the margins of resected brain tumor cavities.

The objectives of this study were to evaluate the safety and performance of a new brachytherapy applicator in the treatment of resected brain tumors in a canine model. The brachytherapy applicator is an inflatable balloon catheter that is implanted in the resection cavity remaining after a brain tumor has been debulked. After implantation the balloon is inflated with Iotrex, a sterile solution containing organically bound iodine-125. The low-energy photons emitted by the iodine-125 deposit a therapeutic radiation dose across short distances from the surface of the balloon. After delivery of a prescribed radiation dose to the targeted volume, the radioactive fluid is retrieved and the catheter removed. Small resections of the right frontal lobe were performed in large dogs. Magnetic resonance (MR) images were obtained and used to assess tissue response and to measure the conformance between the resection cavity wall and the balloon surface. In four animals a dose ranging from 36 to 59 Gy was delivered. Neurological status and histological characteristics of the brain were assessed in all dogs. Implantation and explantation as well as inflation and deflation of the device were easily accomplished and well tolerated. The device was easily visualized on MR images, which demonstrated the expected postsurgical changes. The resection cavity and the balloon were highly conformal (range 93-100%). Histological changes to the cavity margin were consistent with those associated with surgical trauma. Additionally, radiation-related changes were observed at the margins of the resection cavity in dogs in which the brain was irradiated. This balloon catheter and 125I radiotherapy solution system can safely and reliably deliver radiation to the margins of brain cavities created by tumor resection. Results of this study showed that intracranial pressure changes due to balloon inflation and deflation were unremarkable and characteristic of the imaging properties and radiation safety profile of the device prior to its clinical evaluation. Clinically relevant brachytherapy (adequate target volume and total dose) was accomplished in all four animals subjected to treatment.

Endoscopic Diagnostics of Chronic Diseases of the Nasal Cavity in Dogs

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Histological Investigation after Filling of Baked Dental Root Tips in the Cavity of Dog's Mandibular Bone

Histological Investigation after Filling of Baked Dental Root Tips in the Cavity of Dog's Mandibular Bone

Complications of Abdominal Vagotomy in the Dog

In the course of a study of Roux-Y drainage after hemigastrectomy and vagotomy in a canine model, unexpected complications were encountered. In our erst 25 specimens there occurred 3 symptomatic hiatal defects with herniated liver into the left pleural space. Respiratory compromise was the primary symptom of the herniation.The changes in oursurgical technique of vagotomy described belowsolved the problem. A literature search has revealed no speciec technique for vagotomy in the dog. The subdiaphragmatic hiatal anatomy of a dog is different than that of a human. A subdiaphragmatic vagotomy in humans is accomplished through an avascular plane in the hiatus, which is widely separated from the pleurae. We have found that the pleural cavity in dogs extends to the avascular plane of esophageal dissection. The anterior vagus is also different in the dogin that it consists of multiple branches lying between the peritoneum and esophagus, compared to a more discrete nerve trunk in humans. The hepatic anatomy in the dog is characterized by 4 lobes, 4 sublobes, and 2 processes, which are more mobile than the bilobate human liver.These smaller,mobile hepatic lobes in the dogs contributed to their tendency to herniate. We solved the problem and facilitated the dissection by deliberately entering the pleural spaces, easily dissecting the vagi, and repairing the pleurae by approximating the diaphragmatic muscles behind the esophagus. After exposing the esophageal hiatus, an incision is made in the peritoneum between the esophagus and each crus of the diaphragm. Blunt and sharp dissection is used at this point to mobilize the esophagus. It is at this point that the pleural spaces are entered. Pleural defects approximately 3 cm. in length are created. The esophagus is elevated and held using a Penrose drain. Once the pleural space has been entered the posterior vagus is easily identieed as a single trunk 4 mm. in diameter (Fig. 1). The posterior vagus is then doubly clamped and tied after excising a segment. Attention is next turned to the anterior vagal ebers. At this level, the anterior vagus exists as multiple branches (Fig. 2) in the peritoneum and areolar tissue (about 1.5 cm. to 2.0 cm. in width) anterior to the esophagus. This tissue is isolated. Again a segment is excised with each free edge being tied. At this point the esophagus is inspected for any remaining vagal ebers which are removed if identieed.

Intramarrow cytokine gene transfer by adenoviral vectors in dogs.

Daily systemic administration of hematopoietic growth factors can be associated with dose-limiting systemic side effects. To overcome this, we have investigated hematopoietic cytokine gene transfer to the marrow cavity of dogs by direct intramarrow injection of adenoviral vectors. In marrow culture, replication-deficient (E1-deleted) adenoviral vectors were able to transduce marrow stromal cells, demonstrating 30-fold greater expression than from other marrow cell types. High-level (ng/ml) cytokine production from transduced stromal cells persisted for 14 days in culture. Because adenovectors could efficiently transduce marrow stromal cells in culture, we investigated if stromal cells could also be transduced in vivo following direct intramarrow vector injection. Adenovectors with genes for interleukin 6 (IL-6) and Lac Z (beta-galactosidase) were injected directly into the marrow cavity of dogs resulting in protein expression localized to within the treated marrow. To evaluate this approach further in dogs, we constructed a vector expressing biologically active canine granulocyte-macrophage colony stimulating factor (GM-CSF). 293 cells infected with ADGM-CSF demonstrated prevalent GM-CSF mRNA by Northern blot and 135 +/- 30 ng/ml of protein as measured by enzyme-linked immunosorbent assay (ELISA). In vitro bioactivity of protein expressed was confirmed by canine GM colony-forming assay (CFU-GM). In vivo high-level protein production was noted in supernatants of marrow aspirates 72 hr following direct intramarrow administration of ADGM-CSF (baseline mean +/- SEM, 27 +/- 22 ng/ml, 72-hr sample 921 +/- 461 ng/ml). A localized myeloid expansion of marrow and significant peripheral leukocytosis (neutrophilia) were noted in all ADGM-CSF-treated dogs. Peripheral blood changes lasted for up to 3 weeks in dogs following single intramarrow injection. Thus, adenoviral cytokine expression from the marrow of a single large bone (ilium) led to compartmentalized expression of growth factor and an increase of hematopoiesis sufficient to cause peripheral blood changes in a large animal model.

Mechanism of enhanced gastric contractions in response to stimulation of the sympathetic trunk

Stimulation of the sympathetic trunk in the thoracic cavity of dogs was found to result, as a rule, in increased gastric contractions. The stimulatory effect was better defined in the presence of the drug Ornid but could be greatly decreased or completely eliminated by Promedol. It is suggested that the sympathetic trunk contains preganglionic serotoninergic nerve fibers which enhance gastric contractions.

Rate of formation of tertiary dentin in dogs' teeth in response to lining materials

The rate of tertiary dentin produced in response to four lining materials placed in standardized cavities in dogs' teeth was measured over a period of 119 days. Sterile denatured dentin ash was used as a control material in an attempt to quantify tertiary dentin formation in response to cavity preparation. In all periods the amounts of tertiary dentin formed beneath the control material were significantly smaller than those formed beneath any of the four lining materials. In the first 98 days the rate of formation of tertiary dentin beneath calcium hydroxide (Calxyl) was significantly greater than that beneath the material containing corticosteroid (Ledermix cement). In the last 21 days there was no difference in daily rates of tertiary dentin production beneath all of the lining materials. With all the lining materials there was a highly significant difference between the daily amounts of tertiary dentin formed in the first 6 weeks and those in the last 11 weeks.

Haematology and serum biochemistry in the racing greyhound following intraperitoneal povidone-iodine.

Povidone-iodine caused peritonitis with neutrophilic leukocytosis and a minimal left shift at the dosage rate of 3.5 ml/kg body weight. A dosage rate of 2 ml/kg only caused slight neutrophilic leukocytosis. There was a significant increase in the levels of creatinine (p = 0.049) and BUN (p = 0.020) in dogs that received the higher dose rate. Two dogs died from povidone-iodine toxicity with a marked increase in ALT, AP, SDH and conjugated bilirubin. It is concluded that povidone-iodine is unsafe for use in the peritoneal cavity of dogs.

Tertiary dentine formation in dogs' teeth in response to lining materials

The daily amounts of tertiary dentine produced in response to four lining materials, placed in standard cavities in dogs' teeth, were measured over a period of 119 d. In the first 98 d the daily amounts of tertiary dentine formed beneath Calxyl were significantly greater than beneath Ledermix cement. In the last 21 d there were no differences between the daily rates of tertiary dentine production beneath any of the lining materials. With all the lining materials investigated the daily amounts of tertiary dentine formed in the first 6 weeks were significantly greater than those in the last 11 weeks.

Regional protein absorption rates from the pleural cavity in dogs

In five supine spontaneously breathing anesthetized dogs we injected into the pleural space 0.5-1 ml of saline solution containing 2 mg/ml albumin labeled with technetium-99m. By use of a gamma camera placed horizontally over the chest, we followed, up to 120 min, the activity over the whole lung and over the preferential accumulation areas of the label (regions of interest, ROI) that corresponded to the apical, mediastinal, and laterodiaphragmatic regions. Activities were corrected for the decay rate of the isotope used. On the average, the activity over the whole lung decreased by 27% up to 120 min. The overall activity over the ROI amounted to 44.3% after the injection and decreased to 24% of total at 120 min, thus accounting for 75% of the total decrease in activity. At 10 min, the activity per unit surface of the gamma camera image (As) was from 2.2- to 5.7-fold higher over the ROI than for the rest of the lung image. The decrease of As at 120 min was 18-, 13-, and 5-fold greater for mediastinal, diaphragmatic, and apical regions, respectively, compared with the rest of the lung image. The time course of the changes in As are discussed in terms of regional albumin egress rate based on the functional interaction between the Starling and the lymphatic mechanisms.

Identification of blood in the pericardial cavity in dogs by two-dimensional echocardiography

The echocardiographic characteristics of hemopericardium with and without thrombus formation were investigated in 10 dogs and compared with that of saline solution injected into the pericardial cavity. Injection of 80 to 120 ml of saline solution produced an echolucent space between both pericardial layers and was considered as the control image in each dog for comparison with hemopericardium. Injection of heparinized blood filled the pericardial cavity with irregular echoes of variable acoustical impedence. High-density echoes of irregular distribution were observed in 3 dogs, in 5 dogs the echoes were of low acoustical density and in 2 dogs blood echoes were present but scarcely visible. Injection of clotted blood in 9 dogs (adding 20 mg of protamin sulphate and 8 mg of aminocaproic acid) produced echoes of high acoustical density easily identified in the 2-dimensional echocardiographic images. In 4 dogs attenuation and damping controls were increased to the point where myocardial echoes disappeared, while intrapericardial echoes were still visible. Thus, hemopericardium with or without thrombus formation may be identified by 2-dimensional echocardiography and differentiated from other types of pericardial effusion of lower acoustical density. Echogenicity of fluid blood in the pericardial cavity may be related to blood stasis.

Temporary Bilateral Carotid Artery Occlusion During Surgical Exploration of the Nasal Cavity of the Dog

Surgical exploration of the nasal cavity and paranasal sinuses of dogs is often necessary to diagnose or treat conditions causing complete or partial nasal obstruction. Hemorrhage may obscure exploration and be detrimental to the patient. Temporary occlusion of both common carotid arteries reduces blood loss and enhances visualization during rhinotomy. Temporary bilateral common carotid artery occlusion was performed on 15 dogs subjected to nasal exploration. No obvious detrimental effects were noted.

Retrograde catheterization of left heart cavities in dogs by means of an orientable directional Doppler catheter-tip flowmeter: a preliminary report.

A new directional Doppler velocimeter catheter is described bearing a single crystal and mounted on an orientable catheter controller. Retrograde arterial catheterization was performed in six anaesthetized and artificially ventilated dogs through the femoral artery and blood flow velocities were recorded at different sites in the aorta, the left ventricular outflow tract, the left ventricular inflow tract, the left atrium near the mitral annulus, and posteriorly near the venous orifices, and finally in the pulmonary veins. The different recorded patterns are analysed. It is suggested that this procedure might provide a new approach to the study of left heart haemodynamics.

放射線照射下顎骨の即時再移植に関する研究 : 第 2 編 実験的研究

According to Hirakawa and his associates, the healthy bone chips obtaind from areas surrounding osseous lesion of the mandible and alveolar bone were used to fill defects following enucleation of bone lesions. But they didn't applied to malignant tumors because to be in danger of transportation and survival of tumorous cells. Author supposed to this unsolved problem that the transportation and survival of tumorous cells were suppressed by X-ray irradiation and tried follwing experimental research. Bone block and bone chips after 5000R single irradiation were immediately transplanted into the artificial bony cavity in dog's mandible. Author reported the roentogenologic and histopathological observation which revealed the process of the healing. The results were summarized as follows ; 1. From 7-10days to 20-30days after operation, resorption of implants was observed both in bone block group and bone chips group. Further atrophy and disappearance of osteocytes of the implant was more seen in irradiated case than control case. 2. Immature bone formation in bone chips group appeared at about 20days after operation and it was seen early in comparison with bone block group. Moreover vigorous neogenesis of bone fused and surrounded gradually the implants and led to the restoration of the bony defect. The bony healing carried out almost in 60days and accomplished perfectly in 120days after operation, but the healing process in irradiated case was late for time each steps compare with control case. 3. The healing process of the dog's retransplanted mandibular pieces after 5000R single irradiation showed to be similar to the findings of control case with slight delay for time. Author recognized that the irradiated mandibular pieces played the part of implant material finally.

Intestinal and Peritoneal Absorption of Radioiodinated Cholografin and Renografin as an Experimental Test of Gastrointestinal Perforation

During radiographic gastrointestinal examinations with water-soluble diatrizoate compounds (1–5), several investigators (1–3) have observed radiopaque substances in the urinary tract when gastrointestinal perforation was demonstrated. Since it is known that the water-soluble compounds are rapidly eliminated from the blood stream by renal excretion (6), these observations were interpreted as indicating that in the presence of intestinal perforation, significant absorption into the blood stream via the peritoneum occurs. The normal adult intestinal tract rarely absorbs significant amounts of diatrizoates (2, 7). From the previous studies, it seemed that a clinical test for intestinal perforation could be devised from these findings. The authors therefore performed a series of experiments to test the validity of the clinical evaluations and, further, to determine the absorption and distribution of radioisotope-tagged diatrizoate methyl glucarnine (Renografin I125) and iodipamide sodium (Cholografin I131) from the gastrointestinal tract and pertioneal cavity in dogs. In addition, the absorption of Renografin I125 from the gastrointestinal tract in normal man was determined. The use of the radioisotope-labeled compounds suggested an additional means of diagnosis of intestinal perforation which could be rapidly and simply performed at the bedside. Method A. Laboratory Animals: Nine experiments were performed in 7 adult mongrel dogs, 6 female and 1 male, weighing between 11 and 17 kg. Pentobarbital sodium (30 mg/kg, intravenous) was used for anesthesia. The different experiments performed are listed in Table I. Unilateral femoral artery polyethylene cannulas were employed to monitor the blood pressure and to obtain arterial blood samples. In 2 animals hypotension was induced by hemorrhage. Mean aortic blood pressure in these dogs was maintained in the range of 45 to 75 mm mercury. The hypotensive animals were intubated and respirations sustained with a Harvard respirator; in all other dogs only indwelling tracheal intubation was performed. Jugular vein catheters were introduced in 2 dogs and advanced to the level of the right atrium. Urine samples were obtained from the females by in-dwelling soft rubber urethral catheters. In the male, bilateral polyethylene ureteral catheters were inserted through a lateral abdominal extraperitoneal exposure. The test agents were introduced orally by means of rubber gastric tubes. Intra peritoneal injection was accomplished by direct needle puncture of the abdominal wall with a 21 gauge needle. A 1 to 2 ml volume of the test agent was introduced with a 2 cc tuberculin syringe. In dogs receiving the agents orally, an additional 5 ml of isotonic saline was used to express residual test material from the gastric tube into the stomach. The position of the tip of gastric tubes in the stomach was confirmed by auscultation and a test injection of air.

Effects of pure carbon monoxide gas injection into the peritoneal cavity of dogs.

Relatively large quantities of pure carbon monoxide (500 ml) were injected into the peritoneal cavity of normal dogs, CO-acclimatized dogs and altitude-acclimatized dogs. Withdrawal and analysis of the gas at timed intervals revealed a rise in oxygen tension from zero to values which were 2frac12 times the PaOO2. The PiOO2 (intraperitoneal O2 tension) in the acclimatized dogs attained values significantly higher than for the normal dogs. The PiCOCO2 (intraperitoneal CO2 tension) in all dogs approximated the value in normal animals. At no time after the injection did the COHb exceed a 40–50% concentration level. The physiologic mechanism of the observed phenomena is discussed. Submitted on September 22, 1958

Effect of cortisone on the positive potentials induced by glucosamine and amino purines in the synovial cavities of dogs.

Effect of cortisone on the positive potentials induced by glucosamine and amino purines in the synovial cavities of dogs.