Dr Vesela Elenkova – master scintific in veterinary ophthalmology and surgery, veterinary clinic “Eskovet”– Bulgaria, Sofia
Case presentation :
A nine month female rabbit presented for a right eye lesion of two weeks duration. There was cataract on the same eye from birth. The referring veterinarian had prescribed a course of topical and systemic antibiotics but it continued to deteriorate. The eye was become very painful. The lesion appeared as a whitish-yellow mass into the hyperemic iris, slightly protruding into the anterior chamber. There was a mature cataract formation and the pupil was mydriatic with no response to light. The intraocular pressure (IOP) of the affected eye was 40. On the other was 11and it was not clamped. Fluorescein staining was negative for corneal lesions on both eyes. On the ultrasound examination there was no changes into the posterior segment of the affected eye.
The right eye of the rabbit with E.culiculi-assosiated lens-induced uveitis. Note the mature cataract, the large mass into the hyperemic iris and the midriatic pupil not responding to light. IOP is 40.
There was only seen the hyperechogenic lens and the lesion in the iris. The rabbit was in pain when touched and didn’t want to eat well.
Ultrasound image of the eye. Note the hyperehogenic lens and the 7mm lesion behind the iris. The posterior chamber is not affected.
The patient history and appearance of the lesion were compatible with Encephalitozoon cuniculi-induced phacoclastic uveitis, and a tentative diagnosis was made. Other diagnostic defferentials included granuloma caused by Pasteurella or other bacterial infections, but they were unlikely considering cataract formation. Diagnostic included complete blood count, biochemical profile and serology testing.
The complete blood count and serum biochemical profile were within normal limits. The serum IgG-antibodies were not so high, but the IgM-antibodies indicate active infection in most cases. They bought are not indicative for utero infection.
We opted medical management. Except of the antibiotic therapy (with enrofloxacin PO and ciprofloxacin eye drops), the treatment was continued with fenbendazole at 20 mg/kg PO q24h for 28 days. Prednisolone acetate ophthalmic drops were prescribed to treat the uveitis and dorzolamide hydrochloride and timolol maleate drops for the eye pressure.
The left eye of the rabbit appeared unaffected
After one week recheck. The iris is not so hyperemic and IOP is 6.
After 1-week recheck, the lesion had not changed, hyperemia was decreased, the IOP had become low – 6. There was no pain in the eye and the rabbit was doing well. The pupil still does not respond to light. After 2 weeks more, there was no change. The rabbit was in very good condition, but the vision in the right eye was compromised. Surgery might be necessary in the future depending on progression of the lesion, discomfort, and long term effects on the eye.
Encephalitozoon cuniculi (E. cuniculi) is a protozoal parasite. The parasite primarily affects rabbits, but cases have been reported in sheep, goats, dogs, cats, monkeys, guinea pigs, foxes, pigs and humans. It is a recognized zoonosis, but the zoonotic risk seems to be minimal to healthy individuals observing basic hygiene and to date there have been no reported cases of direct transmission from a rabbit to a human. However, those individuals who are immunosuppressed should implement strict hygiene and if possible avoid animals suspected or confirmed of being infected with E. cuniculi. Spores are shed in infected animals’ urine and transmission is usually by ingestion of contaminated food or water, or less commonly by inhalation of spores. Transmission from mother to young (transplacental) also occurs so that offspring are born infected. Most of the time, these organisms do not cause any obvious clinical disease. When E. cuniculi reach nerve tissue, rabbits can experience neurologic impairment, characterized by partial or complete paralysis, loss of coordination, seizures and head tilting.
E.cuniculi-assosiated phacoclastic uveitis is recognized in rabbits. There is no sex predisposition and the condition is often seen in younger rabbits. The mechanism by which the protozoan causes cataract is unclear in detail, but its lifecycle gives clues as to aetiopathogenesis of cataract. Passage of parasite between adult and young happen in utero with the parasite circulating in the fetus and sometimes ending up residing in the developing lens. The parasite migrates through the anterior lens capsule causing liberation of lens protein into the iris and anterior chamber and subsequent development of lens-induced uveitis, however, the posterior chamber usually remains unaffected. Normally this uveitis presents as a white-yellow mass in or near the pupil, sometimes with neovascularisation rendering it red or pink.
Serum ELISA antibody titers are helpful in making a diagnosis, however, serology only indicates past exposure and is not diagnostic of or necessarily correlated with clinical disease and infection. Immunofluorescence assay and polymerase chain reaction (PCR) testing of tissue, urine and feces samples, as well as cerebrospinal fluid and removed lens material. These test looks for antigens, unlike serology, which test for antibodies. Simultaneous testing of IgG and IgM-specific antibodies can give an indication of infection status because IgM antibodies indicate active infection. If transmission is transplacental, bought IgG and IgM antibodies may be low.
In this cases treatment options include antiprotozoal medication, topical corticosteroids for the uveitis, surgery to remove the affected lens and granuloma if it is possible. The other option is enucleation, but it is not common if the eye is functional, because it is unlikely to eradicate the infection. In other cases the eye may atrophy without surgery (phthisis bulbi).
E.cuniculi-assosiated phacoclastic uveitis should be always suspected for rabbits presenting with ocular lesions and uveitis and oral antiprotozoal medications are always recommended, as affected rabbits may develop infection in the brain and encephalitis, that can lead to death.
Dr. Tsvetan Ivanov, “Dobro hrumvane!” veterinary clinics, Sofia, Bulgaria
The most common cause of rear limb lameness in the dog is rupture of the cranial (anterior) cruciate ligament. This derangement results in degenerative changes (osteoarthritis) in the stifle (knee) joint, including cartilage damage, osteophyte (bone spur) production, and meniscal injury. The Tibial Plateau Leveling Osteotomy (TPLO) has proven effective in returning these deranged stifles to full function.
Developed by Dr. Barclay Slocum, TPLO was a radical procedure for addressing canine ACL injuries. Now in existence for over 20 years, the surgery has proven itself, time and time again, to be an extremely effective long term solution for addressing cruciate ligament injury in dogs.
Part of the positive indications for TPLO are:
TPLO is most frequently performed in medium to giant breeds. Greater bodyweight is a positive indicator for selection of TPLO as a treatment option. The procedure can be performed and on small dogs and even cats, but then should be make exact discretion the potential benefits and complications.
Cruciate ligament degeneration is seen increasingly in young large breeds, in some cases within their first year.
Minimising osteoarthritis in the long term is a priority for these young dogs. Many surgeons believe that this leads to the TPLO being the technique of choice, although long term comparative studies continue to investigate this. These cases frequently show bilateral degeneration, and partial cruciate ruptures are common.
The procedure is good option for dogs over 6 months of age, with progression of ossification of proximal tibial growth plates.
Partial ligament rupture.
Cases of partial ligament rupture show a very rapid iprovement following TPLO. Importantly, they typically do not progress to complete ligament failure as TPLO acts to neutralise the forces on the cranial cruciate ligament.
TPLO is widely accepted to give the best functional outcome, in the short to medium term, and has enabled working/performance animals to return to high functional standards.
Excessively sloping tibial plateau:
Average plateau angles range from 22°-26°, but angles from 15° are still remain a TPLO candidate with good post-operative outcome. However, in cases with an increased tibial plateau angle, TPLO has proved particularly beneficial.
Case studies have advocated TPLO as the technique of choice for even small breeds with excessive tibial plateau slopes. In some of those cases the amount of angular correction required leads to a Wedge resection technique being favoured over the Slocum(curved-cut) TPLO.
Cranially translocated tibial crest.
Occasionally the stifle will rest with the tibia cranially translocated following cruciate rupture the tibial crest is palpated cranially, the patella tendon is less distinct, and the first movement during cranial drawer is backwards, often associated with a dramatic degree of movement. In some authors experience these cases may return to cranial translocation with significant recurrence of lameness weeks after extracapsular lateral fabella suture placement. In those cases, in a limited number of procedures, TPLO have shown better outcomes.
Overall, the good TPLO candidate is medium to large breed dog, from 6 months and plus, active, with need of full functional restoration of the limb.
This is the case of Hades. He is oversized cane corso, 6 years old, bodyweight is 78 kg and he suffers from hip arthrosis of the right hip in result of hip dysplasia and chondroma of right carpal bones. He came with lameness on the right rear limb from few weeks, which is worsening. He had and positive “sit and drawer tests.
This is video of his walk:
The diagnosis was cranial cruciate ligament rupture.My favorite procedure is TPLO, but definitely no one can be sure that, the standard procedure can give good outcome with this size dog. Furthermore, the dog have and two other problems on the right side. We were afraid from implant failure so we decided to make insurance. Instead only the TPLO plate we placed and second DCP 3.5 mm plate. The original idea was to use 3.5 screws for the 2-nd plate, but because of the risk from caudal cortex fracture the most distal three screws was 2.7 mm
Those are intraoperative pictures and the immediately post-op pictures:
Video 14 day after the surgery:
X-ray pictures 45 days after the surgery:
45 days post op – LL
45 days post operator
And this is the final result – 6 months after the surgery:
240 days post op
The TPLO remains one of the best surgically ways to manage CrCrLR even in oversized dogs, even with concomitant diseases of the locomotor system.
The most important thing is every surgeon to make optimal assessment of the patient’s status and to remember that every case is specific.