Page 10 - Clinical Connections - Autumn 2023

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Page 10 - Clinical Connections - Autumn 2023
P. 10

RVC RESEARCH    STUDY    VETERINARY SERVICES       RVC.AC.UK
         Ophthalmology

        SNOWFLAKE THE RED-EYED REINDEER

        Maria-Christine Fischer, Lecturer in Ophthalmology, Sara Lawrence-Mills, Senior Clinical Training
        Fellow in Anaesthesia, and Carolina Palacios Jimenez, Lecturer in Anaesthesia
        N     ine-year-old  reindeer  Snowflake   nonpigmented and displayed a not well   canthal pocket syndrome (resulting in
                                              The margin of her left third eyelid was
                                 from
                                       the
                       treatment
                                                                                accumulation of mucoid ocular discharge
              received
                            Service
              Ophthalmology
        neoplastic lesion of the third eyelid.   for  a  defined  mass-like  lesion,  with  an  irregular   in the conjunctival sac), reduced tear
                                            surface on the leading edge, appearing
                                                                                production and prolapse of orbital fat.
          The Ophthalmology Service is primarily   consistent with a squamous cell carcinoma.   Snowflake  in surgery
        based at RVC Small  Animal Referrals,   The remainder of the ocular structures
        but the clinicians also collaborate with the   presented without abnormalities.
        equine, farm animal and exotics teams to   The examination of the back of the eye,
        support patients with eye problems.   the  fundus,  was  a  highlight.  It  revealed
          Snowflake  previously  had  a  squamous   a yellow-green tapetum with prominent
        cell carcinoma mass of the right lower   vasculature and dark optic nerve heads.
        eyelid,  which  was  completely  removed  in   The tapetum is the reflective part of the back
        2018.  Her  owner  brought  her  back  in  this   of the eye that creates the ‘eye shine’ which
        year because they noticed an irregular third   changes colour depending on the season.
        eyelid margin in the left eye.        The ophthalmology team and observing
          Snowflake  lives  in  a  herd  of  about  20   students  found  it  fascinating  to  see
        reindeer and is kept outdoors on grass.   Snowflake’s  tapetum  colour  in  transition
        As she is only very lightly pigmented, she   from winter to summer.  The new fundus
        requires  protection  from  UV  light  in  body   camera, purchased thanks to support from
        area with no or little hair growth. To protect   the  Holliday  Foundation  and  funds  raised   Standing  sedation  was  performed
        her  eyes  she  wears  a  fly  mask  in  the   by the RVC  Animal Care  Trust, enabled   using medetomidine and butorphanol via
        summer.  Her  food  is  supplemented  with   everyone to become part of this unique   intramuscular injection prior to catheter
        moss and lichen, imported from Finland.   experience.                   placement.  Snowflake  was  maintained
                                                                                with variable rate infusion of medetomidine.
        Examination                                                             Positioning Snowflake with her head upright
        On presentation Snowflake was bright and                                helped to prevent any aspiration of saliva.
        in good body condition, weighing 71kg. Both                             Monitoring  included assessment  of  the
        eyes were open and appeared comfortable                                 heart rate, respiratory rate and non-invasive
        and visual. Ocular reflexes and responses                               blood  pressure  as  well  as  capnography
        were present and as expected.                                           (carbon dioxide level) and pulse oximetry
          There  was  no  evidence  of  recurrence                              (oxygen saturation).
        of  the  squamous  cell  carcinoma  on  the                              Supraorbital,     auriculopalpebral,
        lower right eyelid on clinical examination.                             infratrochlear blocks and local infiltration of
        Snowflake  was  diagnosed  with  mild                                   the base of the third eyelid were performed
        cataracts in her right eye, deemed unlikely                             using mepivacaine.  The patient was
        to interfere with her vision.                                           reversed with intramuscular atipamezole to
                                                                                antagonise the medetomidine.
                                                                                 There are few publications detailing
                                                                                anaesthesia in reindeer and this protocol
                                                                                was a novel approach to maintaining a safe
                                                                                level of sedation in a well domesticated
                                             A fundus camera used to examine Snowflake    animal.  The use of these nerve blocks to
                                                                                facilitate ophthalmic surgery have not been
                                            Treatment and anaesthesia           reported before and are in the process of
                                            The third eyelid was removed under sedation   being published.
                                            and after the application of local anaesthetic   Snowflake  made  a  good  recovery  from
                                            blocks and topical tetracaine eye drops.   the surgical procedure and both of her eyes
                                            Cryotherapy was applied to the wound edge   appear to be comfortable. On discharge
                                            as an adjunctive therapy.  The third eyelid   Snowflake  was  prescribed  meloxicam
                                            was  submitted  for  histopathology,  which   (alternate days), gentamycin and bromfenac
                                            confirmed  the  diagnosis  of  squamous  cell   eye drops to prevent infection and reduce
                                            carcinoma. The tumour had been removed   the inflammatory response.
                                            completely.
                                              Risks and complications associated with     For small animal referrals, please call:
                                            the surgery in other species are medial   01707 666399
                                                                                      Email:
         Snowflake and her daugher with the team                                     qmhreception@rvc.ac.uk

        10   Autumn 2023
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