Download Nasolacrimal Drainage System Anatomy and Histology of Reported

Nasolacrimal Drainage System Anatomy and Histology of Reported Animal Models
Article
Burling
Research
Animal
Rabbit
# of
Specimens
16 [9 New
Zealand
White (NZW)
+ 7 lop mixed
breed]
Freeman
Kern
Rabbit
Rabbit
6 NZW
Maeda
Rabbit
19 Japanese
White
Marini
Rabbit
15 NZW
Wilhelm
Rabbit
8 NZW
Paulsen 2002
Rabbit
(histology described
applies to nasolacrimal
duct)
Ape
Pig
Cat
Key Anatomic Findings
Key Histologic Findings
 Single punctum on inner lid surface 3mm from medial
canthus with short canaliculus (2mm) that opens into
lacrimal sac.
 Sac was slightly dilated, funnel shaped portion of duct
 Average duct length 58.8 mm with variable diameter.
 Duct exits within nasal vestibule several mm posterior to
mucocutaneous junction at the alar fold

 Single, large, inferior nasolacrimal punctum opens to a
tortuous nasolacrimal duct of variable diameter

 Sac and duct lined with stratified or
pseudostratified columnar epithelium with
numerous goblet cells.
 Submucosa composed of loose connective tissue
with abundant capillaries and lymphatics.
 Opening of duct into nasal vestibule transitions
from columnar to stratified squamous cells.
 Duct lined with stratified squamous epithelium.

 Single inferior punctum 3mm from inferior palpebral
margin empties into sac.
 Sac marks caudal and dorsal extremities of NLD
apparatus
 Duct courses rostroventromediad through nasolacrimal
canal and exits just caudally to the mucocutaneous
junction of the nares.
 Cavernous body surrounds lacrimal sac and duct
 Duct drains into inferior meatus of nasal cavity

 Sac epithelium had a two-layered columnar
appearance.
 No goblet cells seen.
 Sac and duct lined by single, stratified to
pseudostratified columnar epithelium.
 Numerous mucus-containing cells.
 Proximal duct epithelium had villous folds.
 Submucosa had abundant capillaries, lymphatics,
and other components of loose connective tissues.

 Same histology as ape.
 Epithelial cells covered with microvilli (200-400
nm in length, 60-70 nm in diameter) shown by
scanning electron microscopy.
 Double-layered epithelium with mucin-secreting
epithelial cells organized in cell groups lacking
goblet cells, intraepithelial mucous glands (IMG)
or subepithelial seromucous glands (SSMG).
 Surrounding cavernous body (SCB) present.
 Double-layered epithelium with mucin-secreting
epithelial cells, SCB and SSMG, but lacking
goblet cells or IMG.
 Double-layered epithelium with many goblet cells
but lacking IMG, SSMG or SCB.
Deer
Rat
 Duct exits below the posterior part of the inferior
turbinate into the nose
Paulsen 2000
Rat
Gelatt
Cat
2 short haired
domestic
Dog
14 different
breeds
Yakely
Dog
3 different
breeds
Conlon
Sheep
7
Gilanpour
Sheep
14
Sinha
Sheep
Goat
20
4
 Upper and lower canaliculi roughly equal in length (6-10
mm) and diameter (0.7-1.0 mm).
 Sac roughly triangular, 5mm long, proximal diameter
3mm and distal diameter of 1mm
 Duct 2.5-4cm long, diameter 0.7-1.5mm, proximal 1/3
smaller than distal 2/3.
 Upper and lower canaliculi that consolidate into poorly
developed sac
 Duct has 2 distal openings, with reduced diameter in
proximal third.
 Dimensions of drainage system vary considerably
between species
 No distinct sac; just conjoining of superior and inferior
canaliculi.
 Duct opens 2 cm posterior to external nares on lateral
floor of nasal cavity.

 2 parts; orbit and nasal cavity portions.
 Orbital part: two lacrimal puncta, two canaliculi (7mm
long), and lacrimal sac.
 Distinct sac (6mm long by 5 mm wide): more expanded
than duct but smaller than human sac.
 Nasal cavity: formed by duct leaving the sac in the orbit
and entering osseous lacrimal canal where it exits on
lateral wall of the nostril.
 Total duct length 105-113 mm
 Similar to goat.
 Upper and lower puncta, with corresponding canaliculi
that converge toward medial commissure
 Sac receives both canaliculi laterally and empties into
duct which passes through the osseous lacrimal canal,
parallels the middle meatus, and exits through the
terminal fold of the ventral turbinate and opens on the
nasal mucous membrane above the nostril.
 Double-layered epithelium with SCB but no
goblet cells, IMG or SSMG.
 Multilayered epithelium with goblet cells and
IMG lacking SSMG and SCB.
 Ducts lined with multilayered epithelium
consisting of larger squamous cells above and
cuboidal cells below.


 Canaliculi lined by continuous layer of
nonkeratinized squamous epithelium.

 Similar to goat.
 Punctal margin lined with stratified squamous
epithelium on eyelid border, and typical
conjunctival epithelium adjacent.
 Lacrimal passage epithelium: (1) stratified
squamous in proximal portion of canaliculi, (2)
stratified cuboidal to columnar in middle and
distal regions of canaliculi, (3) stratified and
pseudostratified columnar with goblet cells in
lacrimal sac, and nasolacrimal duct.
Abdalla
Camel
34 dromedary
Latimer
Horse
7
Sapienza
Llama
2
 No puncta
 Funnel shaped sac with 1 or 2 one cm canaliculi ending
blindly 0.5 cm from the medial canthus
1 mm from
upper or lower lids.
 Sac continuous with duct, 3-4 mm wide and 20 cm long,
opens with discrete oval orifice on anterior aspect of
nasal mucous membrane.
 Upper and lower puncta 8-9 mm from medial canthus
with corresponding canaliculi
 Sac identifiable only as a slight dilation at the
convergence of canaliculi before continuing as duct
 Duct narrows before its exit from the bony maxilla in the
lateral wall of middle nasal meatus and continues gentle
spiraling course until emptying onto floor of the nasal
vestibule at the mucocutaneous junction
 Duct length 24-29 cm with 2-11 mm variable diameter
 Ventral and dorsal puncta 4-6 mm from medial canthus,
with paired canaliculi 2-4 mm in length that converge
into rudimentary sac.
 Duct length 11-15 cm with 2-4 mm uniform diameter that
opens on floor of nasal cavity.
 Few seromucous glands surrounding lower third
of nasolacrimal duct.
 Lamina propria of lacrimal sac and nasolacrimal
duct contained abundant venous plexus
resembling erectile tissue.
 Sac lined by several layers of stratified columnar
epithelium with goblet cells.
 Duct lined by stratified columnar epithelium with
basal layer rich in melanin granules and goblet
cells present in middle portion increasing in
number through terminal portion.

