Treatment of congenital extrahepatic portosystemic shunts in dogs : a systematic review and meta‐analysis

Background Several options have been proposed for the treatment of congenital extrahepatic portosystemic shunts (cEHPSS) in dogs, but formal comparisons among different treatment options are currently unavailable. A previous evidence-based review (2012) found low quality of evidence for papers assessing the treatment of cEHPSS in dogs. Objectives To assess the quality of evidence available in the treatment of cEHPSS, summarize the current state of knowledge with respect to outcome after cEHPSS management, and compare different treatment techniques. Animals Not used. Methods A bibliographic search was performed without date or language restrictions. Studies were assessed for quality of evidence (study design, study group sizes, subject enrollment quality, and overall risk of bias) and outcome measures reported (perioperative outcome, clinical outcome, and surgical or interventional outcome), all reported with 95% confidence intervals. A network meta-analysis was performed. Results Forty-eight studies were included. Six retrospective studies (grade 4b) compared 2 techniques and 7 were abstracts (grade 5). The quality of evidence was low and risk of bias high. Regarding surgical outcome, statistically significant superiority of ameroid constrictor over thin film band was observed (P = .003). No other comparisons were statistically significant. Conclusions and Clinical Importance The evidence base of choice of treatment of cEHPSS in dogs remains weak despite recent publications on the subject. Ameroid is superior to thin film band in causing EHPSS closure. Blinded randomized studies comparing different treatment modalities, which routinely include postoperative imaging to assess cEHPSS closure and acquired portosystemic shunt development are essential

Multiple Growth Mechanisms of Jadeite in Cuban Metabasite

Samples of rocks reported in the literature to be jadeite jade from the subduction-zone complex of the Escambray Massif in\ud central Cuba have been studied by optical and transmission electron microscopy, electron microprobe and hot-cathode cathodoluminescence\ud (CL) microscopy. Although these rocks are indeed rich in jadeite, the bulk rock composition generally conforms to\ud MORB, with Na2O enriched by . 3 wt% and CaO depleted by .2 wt%. Al2O3 contents are unchanged. These changes are attributed\ud to early pre-subduction spilitization of the ocean-floor protolith. Relics of magmatic augite preserving an ophitic texture are common.\ud Disequilibrium textures are the rule. Extensively recrystallized rocks show fine, felty intergrowths of predominantly Al-rich\ud glaucophane and jadeite, the latter with rims and patches of omphacite. TEM observations indicate extensive replacement of\ud pyroxene by amphibole. Glaucophane developed rims of magnesiokatophorite and edenite. Chlorite and epidote are also present.\ud Late development of actinolite, chlorite, epidote and albite is observed. Quartz is present. Less recrystallized samples with numerous\ud large (.1.5 mm) grains of augite show several types of sodic and sodic-calcic clinopyroxene development: (1) Topotactic\ud replacement of magmatic pyroxene by jadeite and omphacite along a broad front encroaching upon the augite grain from the rock\ud matrix. Jadeite dominates where presumably plagioclase was formerly present. Omphacite dominates where augite is internally\ud replaced along cleavage and fractures. Late chlorite, taramite and ferropargasite replace these pseudomorphs. (2) Former plagioclase\ud laths of the ophitic fabric are replaced by jadeite together with lesser omphacite in epitactic relationship with the enclosing augite.\ud Former plagioclase-augite grain boundaries remain preserved. Late pumpellyite is associated with the omphacite. (3) Jadeite þ\ud omphacite þ pumpellyite þ chlorite with irregular grain boundaries dominate in the rock matrix between the augite relics, with\ud idiomorphic crystals of epidote scattered throughout and in chlorite–epidote clusters. Pumpellyite is interpreted to be a late retrograde\ud product. Quartz is present. (4) Jadeite þ omphacite þ chlorite assemblages, in which monomineralic sheaf-like jadeite aggregates are\ud common, fill very thin (500–1500 mm) fractures criss-crossing the sample, including ophitic augite remnants. Cathodoluminescence\ud microscopy shows that jadeite in the veins is distinctly different from CL in the other types of jadeite, showing features like oscillatory\ud growth zoning indicative of crystallization from a fluid. Generally omphacite develops irregularly along jadeite rims, but recrystallization\ud may lead to pairs with straight grain boundaries suggestive of phase equilibration. Comparison with published solvus\ud relationships suggests temperatures of 425–500 C. This unusual occurrence of different types of jadeite in a metabasic rock suggests\ud two contrasting sources. The first – in the rock matrix, as topotactic alteration of igneous pyroxene and as plagioclase replacement\ud epitactically growing on augite – can be explained as due to local domain equilibration in a rapidly subducted ‘‘spilitized’’ gabbroic\ud rock. The second, in very thin fracture fillings, conforms to an origin as a crystallization product from a pervasive fluid. Conceivably,\ud ‘‘pooling’’ of the fluids flowing through the fractures in larger cavities could lead to larger masses of jadeitite. These have not yet been\ud conclusively documented in the Escambray Massif

Cerebellar cortical degeneration with selective granule cell loss in Bavarian mountain dogs

Three Bavarian mountain dogs aged between 18 and 20 months, not related to each other, were presented with chronic signs of cerebellar dysfunction. On sagittal T2-weighted magnetic resonance imaging brain images, the tentative diagnosis of cerebellar hypoplasia was established based on an enlarged cerebrospinal fluid space around the cerebellum and an increased cerebrospinal fluid signal between the folia. Post-mortem examination was performed in one dog and did show an overall reduction of cerebellar size. On histopathologic examination, a selective loss of cerebellar granule cells with sparing of Purkinje cells was evident. Therefore, the Bavarian mountain dog is a breed where cerebellar cortical degeneration caused by the rather exceptional selective granule cell loss can be seen as cause of chronic, slowly progressive cerebellar dysfunction starting at an age of several months