-1 shows th he μ and vely.
racted one.
section is m ntation.
ntation
, the second and airway eatured algo proposed an oposed b on scheme [ both accept . proposed stration hav tead of larg is algorithm ecated and re what in ply from her
ection
he optimal t μ are the
manually ex
d stage is to for further orithms that n optimal se by Sluime [18]. Both o table for dir
has lower ve not been ge amount o m are introd
no need t n need in
re.
threshold. It e averaged
xtracted in
o segment r segmentatio t already w egmentation er et al.
of them are rect adaption
complexity taken used f decision r duced below
to apply, th this thesis.
t is an itera intensity o
order to foc
respiratory s on.
ell develope n using optim
. which excellent w n in this the , because m
[6, 37]. It is ules being a w. After all, hat eliminat
In this th
tive proced of the body
cus on the
system in th
ed. One of mal thresho performin works to seg
esis.
machine lea s so fast to applied.
the later p ting trachea hesis, casc
dure selectin y and
non-main
horax
these olding ng a
gment
arning apply
voxe withi
as –1 of bo
3.2.
lungs
It is assum els. Lungs in the body
The initial 1,000 HU. T oth body and
.2 Conne
There exis s. Three dim
ed that the and other those have threshold i The new th d non-body
ectivity a
t some sma mensional c
Figure 3.
T
image conta low density high densit is set to -1,0
reshold in t y voxels with
and Topo
all compon connected c
.3 Unwante
ains only tw y tissues c ty are classi 000 HU be the next ite hin the ches
ological
nents those component
d cavities.
wo types of classified as ified as bod
cause the in ration is the st.
Analysis
are not con labeling is
voxels, bod s non-body
y voxels.
ntensity of e average o
s
nnected to applied to i
dy and non-y voxels. V
air is prede of mean inte
the major identify the
(3-1)
-body Voxels
efined ensity
parts, e lung
regio regio elimi
consi surro
comp lungs comp
on. Compon on, with tin
inated.
Interior ca ist of wate ounding air.
This pheno pliments [22 s. Next, it ponent. The
Fig
nents with ny volume
avities in th er and bloo
These will omenon is sh
2]. At first, finds the e operation c
gure 3.4 Un
the two la and is no
he lungs ar d cell with be removed hown in fig
this algorit complimen can be simp
R ← con
nwanted cav
argest volum ot connecte
re unwante h high dens d during the gure 3.3, and thm, find th
nt region w plified as eq
nncomp R
vities remov
mes are the ed to the l
ed. Vessels sity, are rel e thresholdi
d can be eas he complime which is c quation 3-2
, 1
ved.
e left and r ungs, will
filling wit latively hig ng procedur sily recover ent region o connected w
and figure 3
right lungs be discard
th blood, w gh intensity ure.
red by findi of the segm with the la 3.4.
. The d and
which y than
ng its mented argest
(3-2)
3.3
Airway
Human air on growing
ific criterio applies a ru The detaile ons respecti
.1 Seed S
The seed p en. It is bec ay lumen. T se tissues ha It is trivia rior slice r hea has large
It is import point to the the lumen me affect. I wing proced similar inten bronchus su
lly leaks till
y Segm
rway segm with a seg on from a s
un time dete ed individu ively.
Selection
point is stro cause that th The airway w
ave significa l to find a rather than
er diameter tant to selec e lumen cen
wall, it wi It is highly dure. Voxels nsity retriev urrounded by
l processing
entation
mentation is gmented th
eed point w ermined thre ual procedu
n
ongly sugge he intensity wall has hig antly higher
circular an finding bro than bronch ct a seed poi
nter is, the ill have hig
risky result s belonging ved. The tra
y air or ves g to the bron
n
s implemen horax CT sc which is loc eshold inste ures of seg
ested to be y decreases
gh intensity r density tha nd low int onchi in th hus.
int near the lower the in gher intensi
ting in leak g to the wal achea is sur sel. It rarely nchi which
nted using can. It appl cated at the ead of a fixe mentation
selected fro from airwa y relative to
an air.
ensity area he remainin
center of ai ntensity ret ity than the king into lun
ll are easily rrounded by y leaks whi
are surroun
three-dim lies region e center of ed one.
are describ
om the cent ay wall to t the inside o
in trachea ng slices. It
irway lumen rieves. If a e center one
ng while pe y miss-class y body voxe ile processin nded by alve
mensional se growing w the trachea
bed in follo
ter of the ai the center o of airway lu
a locating a t is becaus
en. The clos seed is obt ne, due to p erforming r sified becau
els in contr ng the trach eolus. tained partial egion use of rast to hea. It
enco point a me by a point point
3.3.
with
While deal untered rela t with much edian filter i
single whi ts. Adding m ts. Seed poi