Migraine-like Episodic Pain Behavior in a Dog: Can Dogs Suffer from Migraines?

Clinical predictors of syringomyelia in Cavalier King Charles Spaniels with chiari-like malformation based on owners' observations

BACKGROUND

Syringomyelia (SM) is a prevalent inherited developmental condition in Cavalier King Charles Spaniels (CKCSs) with Chiari-like malformation (CM), accompanied by a variety of clinical manifestations, including signs of neuropathic pain. Magnetic resonance imaging (MRI) is the gold standard in SM diagnosis. However, it is desirable to establish clinical predictors that can identify CKCSs with a large clinical syrinx that needs treatment, as some owners cannot afford or lack access to MRI. The aims of the study were to investigate owner-reported clinical signs of SM and clinical predictors of a large clinical syrinx, using predictive values of significant signs, individually and in combinations. Eighty-nine CKCSs participated in this retrospective study. Based on MRI diagnosis, dogs were distributed into three groups: CM without syrinx or with a maximum transverse width < 2 mm (n = 13), CM with small syrinx 2.00-3.99 mm (n = 26) and CM with large syrinx ≥4 mm (n = 50). A structured investigator-owner interview using a standardized questionnaire was used to collect data regarding clinical signs of CM and SM. The statistical tests Pearson's chi-square, Fisher's Exact and Spearman's rank order were used to assess the difference in owner-reported signs between groups. For signs with significant differences, positive and negative predictive values (PPV and NPV) were calculated.

RESULTS

Following clinical signs were reported significantly more frequent in dogs with a large syrinx: phantom scratching, bilateral scratching of the neck or shoulder, aversion when that area is touched, or exacerbation of clinical signs when the dog is emotionally aroused. Each individual sign had a high PPV, indicative of a large clinical syrinx. The PPV increased further when the signs phantom scratching, aversion to touch to the head, neck or shoulder, and a preferred head posture during sleep were present in combination.

CONCLUSIONS

Specific clinical signs can be used individually and in combination as clinical predictors of a large clinical syrinx in CKCSs with CM and SM. General practitioners can utilize this information to identify CKCSs with a large syrinx to initiate necessary treatment. This is particularly useful in cases where access to or affordability of an MRI diagnosis is limited.

Hypertensive nonobstructive hydrocephalus as main magnetic resonance imaging feature in a dog with disseminated choroid plexus carcinomatosis

Obstructive or nonobstructive hypertensive hydrocephalus is reported in choroid plexus tumors. Choroid plexus tumors typically present as T2-weighted hyperintense intraventricular masses with occasional cerebrospinal fluid-drop metastasis. Acquired neoplastic nonobstructive hydrocephalus without visible mass lesion in magnetic resonance imaging is not reported in dogs. A 4.5-year-old Rhodesian Ridgeback presented with reduced mental status, unilaterally absent pupillary light reflex, and neck pain. Magnetic resonance imaging revealed a nonobstructive hydrocephalus and widened lumbar subarachnoid space with no evidence of a primary mass lesion. Postmortem examination confirmed a disseminated choroid plexus tumor affecting the ependyma and choroid plexi of all ventricles and the cerebral and lumbar subarachnoid space. Disseminated choroid plexus carcinomatosis should be considered as a possible cause of hypertensive hydrocephalus even in absence of a primary mass.

Cognition and Cognitive Impairment in Migraine

BACKGROUND

Migraine is a complex neurological disorder that affects a significant percentage of the human species, from all geographic areas and cultures. Cognitive symptoms and dysfunctions are interim and disabling components of this disorder and may be related to the brain processes underlying the pathophysiology. Yet they are often undervalued by clinicians. In this review, we present the different types of cognitive dysfunctions associated with migraine and the mechanisms that are potentially causing them.

FINDINGS

While reversible attack-related cognitive dysfunction seems extremely consistent and likely related to functional cortical and subcortical brain changes occurring during attacks, interictal cognitive dysfunction is less consistent and might become more relevant as attack frequency and disease complexity increase. Migraine traits do not seem a predisposition to long-term cognitive decline. Cognitive dysfunction is a frequent manifestation of migraine attacks and may be specific to this disorder; it is important to understand if it could be useful in migraine diagnosis. Attack-related cognitive dysfunction is clinically relevant and contributes to disability, so it should be perceived as a therapeutic target. While there is no evidence to support that migraine increases the risk of long-term or persistent cognitive dysfunction, the fact that it occurs during the attacks and may persist in subjects with frequent or complicated attacks should prompt the understanding of the mechanisms related to its pathophysiology for it may also clarify the processes underlying migraine.

Translational pain assessment: could natural animal models be the missing link?

Failure of analgesic drugs in clinical development is common. Along with the current "reproducibility crisis" in pain research, this has led some to question the use of animal models. Experimental models tend to comprise genetically homogeneous groups of young, male rodents in restricted and unvarying environments, and pain-producing assays that may not closely mimic the natural condition of interest. In addition, typical experimental outcome measures using thresholds or latencies for withdrawal may not adequately reflect clinical pain phenomena pertinent to human patients. It has been suggested that naturally occurring disease in veterinary patients may provide more valid models for the study of painful disease. Many painful conditions in animals resemble those in people. Like humans, veterinary patients are genetically diverse, often live to old age, and enjoy a complex environment, often the same as their owners. There is increasing interest in the development and validation of outcome measures for detecting pain in veterinary patients; these include objective (eg, locomotor activity monitoring, kinetic evaluation, quantitative sensory testing, and bioimaging) and subjective (eg, pain scales and quality of life scales) measures. Veterinary subject diversity, pathophysiological similarities to humans, and diverse outcome measures could yield better generalizability of findings and improved translation potential, potentially benefiting both humans and animals. The Comparative Oncology Trial Consortium in dogs has pawed the way for translational research, surmounting the challenges inherent in veterinary clinical trials. This review describes numerous conditions similarly applicable to pain research, with potential mutual benefits for human and veterinary clinicians, and their respective patients.

Spinal Arachnoid Diverticula: Outcome in 96 Medically or Surgically Treated Dogs

BACKGROUND

Little is reported about the role of medical management in the treatment of spinal arachnoid diverticula (SAD) in dogs.

OBJECTIVES

To describe the outcome of 96 dogs treated medically or surgically for SAD.

ANIMALS

Ninety-six dogs with SAD.

METHODS

Retrospective case series. Medical records were searched for spinal arachnoid diverticula and all dogs with information on treatment were included. Outcome was assessed with a standardized questionnaire.

RESULTS

Fifty dogs were managed medically and 46 dogs were treated surgically. Dogs that underwent surgery were significantly younger than dogs that received medical management. No other variables, related to clinical presentation, were significantly different between both groups of dogs. The median follow-up time was 16 months (1-90 months) in the medically treated and 23 months (1-94 months) in the surgically treated group. Of the 38 dogs treated surgically with available long-term follow-up, 82% (n = 31) improved, 3% (n = 1) remained stable and 16% (n = 6) deteriorated after surgery. Of the 37 dogs treated medically with available long-term follow-up, 30% (n = 11) improved, 30% (n = 11) remained stable, and 40% (n = 15) deteriorated. Surgical treatment was more often associated with clinical improvement compared to medical management (P = .0002).

CONCLUSIONS AND CLINICAL IMPORTANCE

The results of this study suggest that surgical treatment might be superior to medical treatment in the management of SAD in dogs. Further studies with standardized patient care are warranted.

Behavioural and Medical Differentials of Cognitive Decline and Dementia in Dogs and Cats

Cognitive dysfunction syndrome (CDS) is a diagnosis of exclusion given that there is no specific diagnostic test or tool and that medical disorders can cause the same set of signs. The veterinary surgeon must first identify that signs are present, collect a full history and then perform a full physical examination and relevant diagnostic tests to rule out medical causes for the signs including blood and urine analysis, radiographs and diagnostic imaging such as magnetic resonance imaging (MRI) where indicated.