Changes

==Introduction==

==Description==

Dacryocystitis is one of the most common conditions encountered in practice and can be one of the most difficult to treat due to the persistence of the organism involved and the tendency of the condition to recur. It is very important to examine the teeth and both nasolacrimal ducts of every rabbit irrespective of the reason for which the animal is presented for clinical examination.  

Dacryocystitis is one of the most common conditions encountered in practice and can be one of the most difficult to treat due to the persistence of the organism involved and the tendency of the condition to recur. It is very important to examine the teeth and both nasolacrimal ducts of every rabbit irrespective of the reason for which the animal is presented for clinical examination.  

==Aetiology==

==Aetiology==

The prime agent of aetiological significance is [[Cheek Teeth Malocclusion – Rabbit|dental malocclusion]]. The constant growth of the teeth combined with the low bone density of the rabbit skull results in the migration of the roots of the teeth leading to:

The prime agent of aetiological significance is [[Cheek Teeth Malocclusion – Rabbit|dental malocclusion]]. The constant growth of the teeth combined with the low bone density of the rabbit skull results in the migration of the roots of the teeth leading to:

#Invasion of the eye socket by the roots of the molars leading to retrobulbar infection, buphthalmos or simply ocular irritation and epiphora.

#Invasion of the eye socket by the roots of the molars leading to retrobulbar infection, buphthalmos or simply ocular irritation and epiphora.

   

  Microbiological investigation yields profuse growth of many organisms, usually ''Pasteurella multocida'' (Petersen-Jones and Carrington 1988), but ''Staphylococcus'' species and ''Streptococcus'' species, can also be frequently involved. Dacryocystitis can be due to an ascending infection from the nasal cavity via the nasolacrimal duct and is a constituent part of the syndrome of Pasteurella infection in rabbits (Whittaker 1989).

Microbiological investigation yields profuse growth of many organisms, usually ''Pasteurella multocida'' (Petersen-Jones and Carrington 1988), but ''Staphylococcus'' species and ''Streptococcus'' species, can also be frequently involved. Dacryocystitis can be due to an ascending infection from the nasal cavity via the nasolacrimal duct and is a constituent part of the syndrome of Pasteurella infection in rabbits (Whittaker 1989).

A survey conducted by Leo Laboratories in 1994 yielded:

A survey conducted by Leo Laboratories in 1994 yielded:

#''Staphyloccus'' spp. - non-haemolytic, 17 isolates; haemolytic coagulase -ve, 10 isolates; haemolytic coagulase +ve, 5 isolates.

#''Staphyloccus'' spp. - non-haemolytic, 17 isolates; haemolytic coagulase -ve, 10 isolates; haemolytic coagulase +ve, 5 isolates.

#''Streptococcus'' spp. - non-haemolytic, 4 isolates; alpha-haemolytic, 2 isolates  

#''Streptococcus'' spp. - non-haemolytic, 4 isolates; alpha-haemolytic, 2 isolates  

#''Pasteurella'' spp. - Pasteurella aerogenes 2 isolates, ''Pasteurella multocida'' 3 isolates, unidentified ''Pasteurella'' spp. 2 isolates,  

#''Pasteurella'' spp. - Pasteurella aerogenes 2 isolates, ''Pasteurella multocida'' 3 isolates, unidentified ''Pasteurella'' spp. 2 isolates,  

#''Bacillus'' spp. - 7 isolates,  

#''Bacillus'' spp. - 7 isolates,  

#''Corynebacterium'' spp. - 5 isolates,  

#''Corynebacterium'' spp. - 5 isolates,  

#''Enterobacter'' spp. - 3 isolates

#''Enterobacter'' spp. - 3 isolates

#''E coli'' - (non-haemolytic) 3 isolates  

#''E coli'' - (non-haemolytic) 3 isolates  

#''Pseudomonas'' spp. - ''Pseudomonas vesicularis'' 2 isolates, unidentified ''Pseudomonas'' spp. 1 isolate,  

#''Pseudomonas'' spp. - ''Pseudomonas vesicularis'' 2 isolates, unidentified ''Pseudomonas'' spp. 1 isolate,  

#''Branhamella'' spp. - one isolate

#''Branhamella'' spp. - one isolate

#''Proteus'' spp. - one isolate

#''Proteus'' spp. - one isolate

#''Acinetobacter junii'' - one isolate

#''Acinetobacter junii'' - one isolate

#No isolates were detected in 12 specimens.  

#No isolates were detected in 12 specimens.  

==Treatment==

==Treatment==

The condition is very difficult to treat as tooth roots are an important factor in the persistent eye infections of rabbits and the distal naso-lacrimal duct may become involved with periapical abscessation of the maxillary incisors (overlong incisor root with thinning or periosteal proliferation of the palatial bone). Dental conditions do not, generally speaking, resolve quickly in rabbits, if at all. Also the causative organism, particularly if it is the ubiquitous ''Pasteurella multocida'', seems to be well adapted to the conjunctival microclimate and local immunity appears to be suppressed. In addition, cannulation of the entire course of the lacrimal duct is impossible due to the tortuous course and varying diameter of the duct although flushing from the lacrimal punctum is possible (Burling et al 1991). Even if the condition is discovered only co-incidentally when the rabbit is presented for some other reason, the following approach should be undertaken:  

The condition is very difficult to treat as tooth roots are an important factor in the persistent eye infections of rabbits and the distal naso-lacrimal duct may become involved with periapical abscessation of the maxillary incisors (overlong incisor root with thinning or periosteal proliferation of the palatial bone). Dental conditions do not, generally speaking, resolve quickly in rabbits, if at all. Also the causative organism, particularly if it is the ubiquitous ''Pasteurella multocida'', seems to be well adapted to the conjunctival microclimate and local immunity appears to be suppressed. In addition, cannulation of the entire course of the lacrimal duct is impossible due to the tortuous course and varying diameter of the duct although flushing from the lacrimal punctum is possible (Burling et al 1991). Even if the condition is discovered only co-incidentally when the rabbit is presented for some other reason, the following approach should be undertaken:  

*Make sure that the dental disease is thoroughly addressed.

*Make sure that the dental disease is thoroughly addressed.

*Under local analgesia using proxymetacaine hydrochloride BP (Minims; Alcon), I canulate the lacrimal duct as described by Petersen-Jones and Carrington (1988) and flush the apparatus (irrigating canula reference AS85 from Arnolds Veterinary Products, or iv cannula) with sterile saline until the fluid runs clear from the the nares. The bevelled end of the Surflo intravenous canula makes it an easier instrument for this purpose. The apparatus is then irrigated diluted ophthalmic preparations of antibiotics, ideally following microbial cultures and sensitivity testing.  

*Under local analgesia using proxymetacaine hydrochloride BP (Minims; Alcon), I canulate the lacrimal duct as described by Petersen-Jones and Carrington (1988) and flush the apparatus (irrigating canula reference AS85 from Arnolds Veterinary Products, or iv cannula) with sterile saline until the fluid runs clear from the the nares. The bevelled end of the Surflo intravenous canula makes it an easier instrument for this purpose. The apparatus is then irrigated diluted ophthalmic preparations of antibiotics, ideally following microbial cultures and sensitivity testing.  

*In some cases it is impossible to effect drainage of the tenacious purulent material. I once had success with a solution of trypsin is infused into the duct and the procedure is reattempted after twenty-four to forty-eight hours.  

*In some cases it is impossible to effect drainage of the tenacious purulent material. I once had success with a solution of trypsin is infused into the duct and the procedure is reattempted after twenty-four to forty-eight hours.  

*Follow-up treatment comprises systemic and topical antibiosis, usually with oxytetracyline (Engemycin® 5%; Intervet) and tetracycline ophthalmic ointment (Fucithalmic®; Leo) or gentamicin (Tiacil®; Virbac) applied to the conjunctival fornix q 6-8 hrs, or antibiotics are select­ed after sensitivity testing. In the absence of antibiotic sensitivi­ties. I have noticed that topical applications of ophthalmic preparations containing neomycin are frequently not effective in the treatment of this condition.

*Follow-up treatment comprises systemic and topical antibiosis, usually with oxytetracyline (Engemycin® 5%; Intervet) and tetracycline ophthalmic ointment (Fucithalmic®; Leo) or gentamicin (Tiacil®; Virbac) applied to the conjunctival fornix q 6-8 hrs, or antibiotics are select­ed after sensitivity testing. In the absence of antibiotic sensitivi­ties. I have noticed that topical applications of ophthalmic preparations containing neomycin are frequently not effective in the treatment of this condition.

*Whittaker (1989)

*Whittaker (1989)

[[Category:Ophthalmological_Disorders_-_Rabbit]]

[[Category:Rabbit Opthalmology]]