Proximal suspensory desmopathy in hindlimbs: Magnetic resonance imaging, gross post-mortem and histological study.

BACKGROUND: There have been no previous studies correlating high-field magnetic resonance imaging (MRI) findings with gross and histological post-mortem examination in horses with hindlimb proximal suspensory desmopathy (PSD). OBJECTIVES: To determine if adhesions between the suspensory ligament (SL) and adjacent tissues could be detected using high-field MRI and if collagen, adipose tissue and muscle pathology could be differentiated. STUDY DESIGN: Retrospective study. METHODS: Nineteen horses with hindlimb PSD were humanely destroyed; 12 limbs of 11 horses with PSD underwent high-field MRI. All lame limbs were examined grossly and all SLs were examined histologically. The MR and histological images were graded blindly. Statistical analysis used a numerical Bayesian approach to simultaneously determine a pathology rating and the contribution of each MRI, gross post-mortem and histological observation to this measure. RESULTS: Signal intensity (SI) in the collagenous tissue was abnormal in 2/12 limbs. Abnormalities of SI in the adipose tissue and muscle were identified in 6 and 11 limbs, respectively. Adhesions between the SL and adjacent tissues were suspected in eight limbs, but only confirmed in six limbs. Histopathological observations of abnormal muscle tissue were associated most closely with the measure of disease used in the study and were abnormal in every limb. Gross adhesions were also a sensitive indicator, along with changes to nerves which were observed in 10 limbs. Assessments of adipose tissue signal intensity and muscle tissue signal homogeneity in both lobes of the suspensory ligament were the MRI indicators most closely associated with the measure of disease. MAIN LIMITATIONS: Small sample size. Model assumption that all abnormalities reflected degrees of a single disease. CONCLUSIONS: Adhesion formation between the SL and adjacent structures was detected by high-field MRI with reasonable accuracy. Muscle and adipose tissue pathology was identified either alone or in association with collagenous tissue pathology.

Histological Features of the Distal Third Metacarpal Bone in Thoroughbred Racehorses, With and Without Lateral Condylar Fractures.

A detailed histopathological study of the distal third metacarpal bone of Thoroughbred racehorses was undertaken to characterize lesions observed previously on magnetic resonance imaging (MRI). The bones were selected and grouped on the basis of MRI features. Representative sections in different planes were processed for histopathology. All lesions observed in the articular cartilage (AC) and subchondral bone (SCB) were recorded and graded with a scoring system, based partially on the Osteoarthritis Research Society International grading system. The scoring system included the severity of the lesion. Descriptive statistics and linear mixed effects models were performed. A positive correlation was observed between the severity of histopathological changes in the superficial and deeper osteochondral tissues, and between the number of race starts and AC score. Age was not correlated with AC or SCB score. A moderate variation in AC and SCB scores was observed between the groups; however, there were differences within individual bones. Bones with focal palmar necrosis (FPN) showed significant differences in the histological scoring of the AC compared with bones without FPN. Bones with incomplete fractures or larger areas of bone remodelling showed significant differences in SCB pathology when compared with bones with FPN. Haematoidin was detected in areas with excessive SCB and cancellous bone sclerosis and/or irregular bone density. This finding is suggestive of poor blood perfusion in these areas.

Proximal suspensory desmopathy in hindlimbs: A correlative clinical, ultrasonographic, gross post mortem and histological study.

REASONS FOR PERFORMING STUDY: It has been suggested that ultrasonography is unreliable for the detection of hindlimb proximal suspensory desmopathy (PSD) based on comparisons between ultrasonographic and magnetic resonance images. OBJECTIVES: To compare ultrasonography with gross and histopathological post mortem examination in horses with PSD diagnosed based on ultrasonography and control horses. STUDY DESIGN: Retrospective descriptive study. METHODS: Part 1: 19 horses with hindlimb PSD and 10 control horses were humanely destroyed. Twenty control limbs and 37 lame limbs were examined grossly and 40 suspensory ligaments (SLs) were examined histologically and graded blindly. Part 2: 3 horses with recurrent lameness after surgical management of PSD and 4 with PSD were assessed ultrasonographically and by gross post mortem examination. RESULTS: Part 1: ultrasonographic lesions were graded moderate in 31/38 (81.6%) and severe in 7/38 (18.4%) lame limbs; in 4/37 (10.8%) limbs adhesion formation between the proximal aspect of the SL and the accessory ligament of the deep digital flexor tendon was predicted. Gross post mortem and histological examinations of control limbs revealed no abnormalities. Gross post mortem examination revealed substantial adhesions between the proximal aspect of the SL and adjacent soft tissues in 10/37 (27.0%) lame limbs; in 10/37 (27.0%) limbs there were adhesions between the body of the SL and the mid plantar aspect of the third metatarsal bone, extending distally in 6 (16.2%) limbs. Histology revealed abnormalities (grades 1-3) of the collagenous tissue in 25/36 (69.4%) limbs; muscle was abnormal (grades 1-3) in 35/36 (97.2%) limbs and adipose tissue (grades 1-3) in 16/36 (44.4%) limbs. Part 2: adhesions between the SL and adjacent soft tissues were predicted ultrasonographically and confirmed post mortem. CONCLUSIONS: Ultrasonography was reliable for the detection of SL pathology based on histology as the gold standard. Adhesions may be a reason for recurrent lameness after surgery.

Serum bile acid concentrations, histopathological features, and short-, and long-term survival in horses with hepatic disease.

BACKGROUND: Serum bile acid concentrations (SBA) and a histopathological biopsy score [Equine Vet J 35 (2003) 534] are used prognostically in equine hepatic disease. HYPOTHESIS: Histopathologic features and scores, but not SBA, differ between survivors and nonsurvivors and correlate with histopathologic evidence of hepatic inflammation and fibrosis. ANIMALS: Retrospective study. Records (1999-2011) of horses with hepatic disease diagnosed by biopsy and with concurrent measurements of SBA. METHODS: Retrospective cohort study. Biopsies were examined for inflammatory cell infiltration including type and distribution, fibrosis, irreversible cytopathology affecting hepatocytes, hemosiderin, or other pigment deposition and bile duct proliferation. SBA, histopathological findings and a histological score [Equine Vet J 35 (2003) 534] were compared between short- (survival to discharge) and long-term (>6 months) survivors and correlations between SBA and histopathological findings investigated. RESULTS: Of 81 cases 90% survived short-term and 83% long-term. Short-term and long-term nonsurvival were associated with SBA (P = .009; P = .006), overall (P = .001; P = .002) and parenchymal (short-term only; P = .01) inflammation, portal and bridging fibrosis (all P < .001), apoptosis or single cell necrosis (P < .001; P = .008), hemosiderin deposition in hepatocytes (P = .011; P = .028), biliary (both P < .001), vascular (P = .003; P = .045) and endothelial (P < .001; P = .02) hyperplasia, nucleic changes (P = .004; P < .001) and the histopathological score (both P < .001). SBA were significantly and positively correlated with overall (P = .001), parenchymal (P < .001) and portal (P = .004) inflammation and portal (P = .036) and bridging (P = .002) fibrosis. CONCLUSIONS AND CLINICAL IMPORTANCE: SBA, histopathological findings and scores differ between survivors and nonsurvivors. SBA concentrations are associated with inflammation and fibrosis suggesting interference with hepatic function. A histopathological score >2 and, less so, SBA >20 µmol/L are specific but not sensitive indicators of nonsurvival.

Intra-abdominal blockage of a ventriculoperitoneal shunt by a suspected mesenteric pseudocyst in a dog.

BACKGROUND: There are few reports of abdominal complications following ventriculoperitoneal (VP) shunt placement for the treatment of hydrocephalus in dogs. CASE REPORT: A 3-year-old dog underwent successful VP shunting for the treatment of hydrocephalus, but re-presented 10 months later with progressive central vestibular syndrome. Magnetic resonance imaging of the brain suggested VP catheter obstruction. The dog was euthanased and on postmortem examination the abdominal tip of the VP catheter was ensheathed and blocked by fibrous mesentery, possibly a pseudocyst. CONCLUSIONS: Abdominal complications are common in humans, with pseudocysts reported in up to 4.5% of cases. This diagnosis should be considered for dogs re-presenting following VP shunt surgery.

Determination of Clobazam, Clorazepate, Flurazepam and Flunitrazepam in pharmaceutical preparations.

The separation of four benzodiazepines (Flurazepam, Flunitrazepam, Clobazam and Clorazepate) in pharmaceutical products by micellar electrokinetic chromatography (MEKC) is described. It was carried out at 25 degrees C and 25 kV by using a 57 cm (50 cm to the detector)x75 mum i.d. fused silica capillary and a 15 mM borate buffer (pH 9.2), 35 mM sodium dodecylsulfate (SDS) and 35 mM sodium deoxycholate water solution. Under these conditions, the analysis was performed in 8 min with acceptable limits of quantification (between 3 and 5 mg l(-1)). The method has been applied for quantifying these benzodiazepines in serum and different commercial formulations with recoveries near 100%.

Micellar electrokinetic capillary chromatography as an alternative method for the determination of ethinylestradiol and levo-norgestrel.

A method for quantifying of ethinylestradiol (ETE) and levo-norgestrel (LEV) in pharmaceutical products by micellar electrokinetic chromatography (MEKC) is described. The separation was carried out at 25 degrees C and 25 kV, using a 20 mM borate buffer (pH 9.2), 15 mM sodium dodecylsulfate (SDS) in 30% acetonitrile/water (v/v). Under these conditions the analysis takes about 7 min. The method has been applied for quantifying both compounds in six different commercial contraceptives and the proposed method gave good results when compared with a reference liquid chromatographic (LC) method.