Hi again,



I'm not sure what type of dogs you are breeding or whether these hydrocephalic pups were clinical i.e. showing signs of the disease. There are breeds such as the Chihuahuas and the Toy Poodles which are still considered "normal" by breeders when they have open fontanelles and subclinical hydrocephalus. To complicate matters more, there hasn't been a lot of research done in the area of hydrocephalus genetics. To most doctors, we consider it a condition passed down from parents to offspring.



Based on the information which you presented to me, my advice would be to not breed these parents again. If the affected pups have lived, then you don't want to breed those dogs either. If the bitch or the stud are valuable, then you may want to consider breeding to another line where there are no signs of hydrocephalus.



I hope this helps,

drphilvegasvet

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Replying to:

Thank you I think I understand the gist of the article, but being a lay person it is quite difficult. However, do you know if there is anyway to find out if the mother of these pups could be a carrier or if this is genetic where it might have come from in my line. This is the first time I have ever seen this in any of my puppies and we had such high hopes for the mother of these puppies to produce something really wonderful. Now I'm not sure if I should spay her and removed her from my breeding program? Quite a dilema for us.



Thanks

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Replying to:

Here is an article which I copied directly from a vet forum. Let me know if you need any more information or would like clarification.

drphilvegasvet





Congenital Hydrocephalus1-7

Synonyms:

Water on the brain

Disease description:

Hydrocephalus is increased accumulation of cerebrospinal fluid (CSF) within the ventricles of the brain. It may occur because of increased production, decreased CSF absorption, and obstructed CSF flow. Increased intracranial pressure due to hydrocephalus may cause disruption of the septum pellucidum, atrophy of the subcortical white matter, optic radiation, internal capsule, and auditory radiation. The ventricles may increase tremendously in size reducing cortical thickness markedly. Portions of the cerebellum and medulla may herniate through the foramen magnum. Hydrocephalus may result in marked neurological impairment and seizures or surprisingly no impairment at all. Hydrocephalus can be divided into two etiological categories: congenital and acquired.

Congenital hydrocephalus is associated in dogs with domed-shaped heads (chihuahuas, terriers, brachiocephalic breeds) and is suspected to be caused by genetic components. However, congenital hydrocephalus can also be caused by periventricular encephalitis or ventriculitis. 5

With congenital hydrocephalus, an open fontanelle(s) (soft open spot in cranium) on the dorsal skull surface is often palpable. And the eyes may be deviated ventro-laterally due to orbital malformation (setting sun sign). Clinical signs may or not be present. Signs may include a spastic gait, seizures, dementia, circling, and learning disabilities (housetraining may be difficult). Although one would assume that signs might be related to size of the ventricles and how much adjacent cerebral and brain stem matter are compromised, one study found a poor correlation between ventricular size and clinical signs. 3 If a fontanelle is present, ultrasound can be done through the fontanelle to image the dilated lateral and third ventricles. Brain scans also demonstrate the dilated ventricles.

Congenital hydrocephalus may occur as the only congenital malformation or defect or can occur in conjunction with other defects. The Dandy-Walker syndrome is a congenital malformation of the cerebellum associated with cysts arising from the 4th ventricle, dysgenesis of the cerebellar vermis, and hydrocephalus of the 3rd and lateral ventricles. Ultrasonography may reveal the dilated ventricles but brain scanning is the best means of diagnosing the cerebellar abnormalities. 8-9

Acquired hydrocephalus ***ATTACH LINK HERE***occurs when the flow of CSF is blocked by a mass or infection. It often results in dilation of one lateral ventricle or dilation of third or fourth ventricles, depending on where the obstruction is located. These cases do not have a palpable fontanelle since the skull was formed properly at birth. Thus there is no way to diagnose acquired hydrocephalus without brain CAT or MRI scanning. It is difficult to know which clinical signs are due to the acquired hydrocephalus and which are due to the cause of the obstruction.

Etiology:

Congenital

Genetic, hereditary

Breed predilection:

Boston terrier

Chihuahua

English bulldog

Manchester terrier

Pekingese

Toy French poodle

Yorkshire terrier

Age predilection:

Juvenile

Newborn

Clinical findings:

ATAXIA, INCOORDINATION

BEHAVIOR CHANGE

BLINDNESS

Calvarium enlarged, fontanel open

CENTRAL NERVOUS SYSTEM (CNS) SIGNS

Coma, unconsciousness

CONVULSIONS

Crying, vocalization

Deafness

Depression

Dysmetria

GAIT ABNORMAL

Hyperexcitability

Hypermetria

Malaise

Mydriasis

Setting sun sign

Sleep inappropriate

Strabismus ventrolateral

STRABISMUS, EYE DEVIATION

Stupor

Diagnostic procedures: Diagnostic results:

Radiography of skull Cranial sutures open

Gyral pattern decreased



Ultrasonography Dilated ventricles



*Magnetic resonance imaging or CAT scan Cerebral ventricles dilated

HydrocephalusDilated ventricles



Electroencephalography (EEG) High voltage, slow wave activity



Necropsy HydrocephalusDilated ventricles

Treatment/Management/Prevention:

SPECIFIC

1) Acute signs of hydrocephalus should be treated with:

a) Dexamethasone: 0.2 mg/kg IV q24-48h for 1-4 days:

b) Prednisone: 1-2 mg/kg PO daily until signs subside:

c) Furosemide: 5 mg/kg PO, IM, SC q12h: Can use alone or in combination with prednisone if case does not respond to prednisone.

d) Phenobarbital See Note) 2.5 mg/kg IV, IM q8-12h: Used in cases where quick control of seizures is needed. Then begin oral phenobarbital.

e) Phenobarbital: 2.0 mg/kg PO q12h indefinitely: To prevent seizures in cases that have repeated seizures (epilepsy). Dogs receiving phenobarbital may have significant artificial lowering of total thyroxine and increase in thyroid stimulating hormone. When measuring serum phenobarbital levels do not use serum separator tubes because they give decreased levels of the drug.

f) Surgical intervention with ventriculo-venous shunts may relieve intraventricular pressure.

SUPPORTIVE

a) Avoid head trauma; don't palpate fontanelle aggressively.

b) Avoid avoid seizure inducing conditions: hypoxia, acidosis, phenothiazine tranquilizers.

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Replying to:

I'm looking for information on hydrocephalus in small puppies (2 weeks). I would like some genetic, hereditary information if there is any out there.