Correlative imaging findings in seven dogs and one cat with spinal arachnoid cysts

Information regarding 7 dogs and 1 cat with a spinal arachnoid cyst is presented. All patients were evaluated with survey radiographs and myelography. Computed tomography (CT) following myelography, magnetic resonance (MR) imaging, and sonography, were used in some of the patients. These imaging techniques were evaluated to determine their efficacy in diagnosing arachnoid cysts, ascertaining the extent and internal cyst architecture and detecting associated spinal cord abnormalities. Survey radiographs were nondiagnostic in all patients. Myelographically, the arachnoid cyst was visible in all patients, with partial blockage to flow of contrast medium. CT provided additional information on localization and lateralization of the cyst, and allowed measurement of the degree of spinal cord compression. MR imaging enabled identification of an associated syringomyelia. Sonography was useful for defining the cyst wall and characterizing the internal architecture of the cyst cavity and adjacent spinal cord. Measurements of the degree of spinal cord compression could be made and were similar to measurements made from CT. Additionally, sonography was considered a useful technique for orientating the surgeon to the location and extent of the cyst. In the absence of the availability of CT or MR imaging for evaluating patients with an arachnoid cyst, sonography is considered a valuable technique for directly assessing the spinal cord for associated disease. Decompressive surgery was performed on 4 dogs and 1 cat, all with successful outcomes

Computed Tomography-guided fine-needle aspiration and tissue-core biopsy of bone lesions in small animals

Nell'uomo, la biopsia TC-guidata a mano libera è un metodo accurato per ottenere dei campioni di tessuto. Ci sono pochi lavori di questa tecnica in medicina veterinaria. Nel presente studio, 21 cani e 2 gatti sono stati sottoposti a biopsia TC-guidata (17 animali) o ago aspirato fine TC-guidato (6 animali) di lesioni ossee. Due delle 17 biospie sono state anche sottoposta ad esame colturale. Tutte le 17 biospie erano diagnostiche (accuratezza 100%). Cinque dei sei aghi aspirati fini erano diagnostici (accuratezza 83.3%). L'accuratezza totale era 95.7%. In un aspirato, la qualità citologica è stata considerata insufficiente in quanto conteneva solo sangue. Non si sono evidenziate complicazioni maggiori. Sono state diagnosticate 14 lesioni neoplastiche, 2 infezioni, e 6 lesioni benigne. L'esame TC dopo somministrazione di mezzo di cotnrasto endovenoso ha aggiunto informazioni utili per evitare grossi vasi e per biopsare tessuto vitale. La bipsia e l'ago aspirato fine TC-guidati a mano libera sembra essere una tecnica sicura e molto accurata per la diagnosi di patologie ossee nei piccoli animaliIn humans, free-hand computed tomography (CT)-guided biopsy is an accurate method to obtain a tissue sample. There are only a few reports of this technique in veterinary medicine. In the present study, 21 dogs and two cats underwent a free-hand CT-guided tissue-core biopsy (17 animals) or fine-needle aspiration (six animals) of a bone lesion. Two out of 17 tissue-core samples were also cultured. All 17 tissue-core biopsy samples were diagnostic (accuracy of 100%). Five out of six aspirates were diagnostic (accuracy of 83.3%). The overall accuracy was 95.7%. In one aspirate, cytologic quality was insufficient containing only blood. No major complications were encountered. Fourteen neoplastic, two infectious and six benign lesions were diagnosed. CT examination after intravenous contrast medium added useful information to avoid large vessels and to biopsy-viable tissue. Free-hand CT-guided tissue-core biopsy and aspiration appears to be a safe and very accurate procedure for use in the diagnosis of bone-associated diseases in small animal