This document contains 34 figures showing various ultrasound images of female pelvic structures and pathologies. The images depict normal anatomy as well as common gynecological conditions including uterine fibroids, endometrial polyps, ovarian cysts, and more. Brief captions accompany each image to describe the clinical findings and significant features.
3. • Fig. 34.1 Sagittal transabdominal scan (IAS)
showing measurement of uterine size (white
crosses) and a moderately thick luteal phase
endometrium (arrowheads). Arrows indicate
vaginal walls.
4. • Fig. 34.2 Sagittal TAS. Deformity of the
bladder base and acoustic shadowing due to
a vaginal tampon (arrows).
5. • Fig. 34.3 Endovaginal scan (EVS). Measurement of the
endometrium (black arrows). Note there are five layers
included in the measurement but the deeper
hypoechoic layer (white arrows) is not included. The
central echogenic line (black arrowhead) is due to the
interface of the two layers of endometrium.
6. • Fig. 34.4 EVS. Small flecks of calcification
(arrows) at the myometrial endometrial
interface representing tiny insignificant
fragments of retained placenta following
pregnancy.
7. • Fig. 34.5 EVS. Normal quiescent ovary lying
on the iliac vessels.
9. • Fig. 34.7 EVS. Power Doppler showing uterine
artery (arrows) running alongside the uterine
body.
10. • Fig. 34.8 EVS. Dominant follicle (arrows)
developing in a normal ovary.
11. • Fig. 34.9 EVS. Clot retraction within a normal
corpus luteum (arrows). The angular margins
and lack of blood flow within the solid
triangular area confirm this is clot rather than
a solid nodule.
12. • Fig. 34.10 (A) EVS. Irregularly shaped echogenic
cyst (arrowheads) due to a collapsing corpus
luteum. (B) Colour Doppler. Flow around the
corpus luteum (arrows) due to neo
vascularisation.
13. • Fig. 34.11 Corpus luteum. Spectral Doppler
shows low impedance flow with RI of 0.57.
14. • Fig. 34.12 EVS. Polycystic ovary with
peripheral cysts.
15. • Fig. 34.13 TAS. Polycystic ovary. Central and
peripheral cysts.
16. • Fig. 34.14 TAS. Multifollicular ovary (arrows)
in a patient with amenorrhoea due to
anorexia nervosa.
17. • Fig. 34.15 TAS. Thickened irregular
endometrium (arrows) due to tamoxifen.
Note the small cysts (arrowheads) at the
myometrial endometrial interface.
18. • Fig. 34.16 TAS. IUCD (arrow) in the cervical
canal.
19. • Fig. 34.17 TAS. IUCD embedded in the
myometrium (arrow), well outside the cavity
(arrowheads).
20. • Fig. 34.18 16-year-old girl with cyclical abdominal pain found to have a
didelphys uterus with a complete vaginal septum and imperforate
hymen on the left. (A) Longitudinal scan demonstrates a large
heterogeneous mass (arrows) due to blood-filled distended vagina. A small
uterus and cervix (arrowheads) can be seen at the upper margin of the
mass. (B) Longitudinal scan to the right of (A) shows a further uterus
(arrowheads mark the position of the endometrium). The normal right
vagina is compressed and hence not visible. (C) Transverse scan confirming
two uterine bodies. (D) Intravenous urogram. Solitary but duplex kidney
on the left.
21. • Fig. 34.18 16-year-old girl with cyclical abdominal pain found to have a
didelphys uterus with a complete vaginal septum and imperforate
hymen on the left. (A) Longitudinal scan demonstrates a large
heterogeneous mass (arrows) due to blood-filled distended vagina. A small
uterus and cervix (arrowheads) can be seen at the upper margin of the
mass. (B) Longitudinal scan to the right of (A) shows a further uterus
(arrowheads mark the position of the endometrium). The normal right
vagina is compressed and hence not visible. (C) Transverse scan confirming
two uterine bodies. (D) Intravenous urogram. Solitary but duplex kidney
on the left.
22. • Fig. 34.19 TAS. Two separate uterine horns
indicative of bicornuate uterus. Arrowheads
indicate position of endometrium.
23. • Fig. 34.20 EVS. Two endometrial echoes
(arrows) within the uterus, suggestive of a
uterine septum.
24. • Fig. 34.21 (A) TAS. Fibroid polyp (arrows) within
the cervical canal. The stalk of the polyp
(arrowheads) can be seen in the uterine cavity.
(B) TAS. Same patient 6 months earlier. The
fibroid polyp (arrows) is now seen within the
uterine cavity.
25. • Fig. 34.22 TAS. Typical mural fibroids (arrows)
abutting but not displacing the cavity
(arrowheads). The larger fibroid shows typical
recurrent shadowing.
26. • Fig. 34.23 TAS. Two subserosal fibroids
(arrows). Arrowheads indicate position of
uterine cavity.
28. • Fig. 34.25 TAS. Irregular area of increased
reflectivity in the centre of a fibroid due to
degeneration.
29. • Fig. 34.26 EVS. Adenomyosis. Coarse
myometrial texture with small cysts due to
blood lakes.
30. • Fig. 34.27 EVS. Multiple endometrial polyps.
Note the midline echoes due to the endometrial
interface (arrows) are displaced by the polyps.
This is a useful feature when trying to
differentiate hyperplasia from polyps.
31. • Fig. 34.28 EVS. Endometrial thickening. This
looks like hyperplasia but subsequent saline
hysterography demonstrated it to be a polyp.
33. • Fig. 34.30 EVS. Poorly defined intrauterine
mass due to endometrial carcinoma.
34. • Fig. 34.31 TAS. Obstructed uterus. The cavity
(arrows) is distended by blood with a
polypoid mass just above the internal os due
to endometrial carcinoma.
35. • Fig. 34.32 TAS. Carcinoma of cervix. Large
irregular cervix (arrowheads) with a small
tongue of tumour (arrow) extending towards
the bladder.
36. • Fig. 34.33 TAS. Cervical carcinoma invading
bladder base (arrows) and causing an
obstructed uterus (arrowheads).
37. • Fig. 34.34 EVS. Fimbrial cyst adjacent to
ovary.
38. • Fig. 34.35 EVS. Hydrosalpinx (arrows)
adjacent to the ovary (arrowheads).
40. • Fig. 34.37 TAS. Bilateral endometriomas.
Note the fluid level on the left and the
irregularly thickened wall.
41. • Fig. 34.38 TAS. Endometriosis. Complex
ovarian mass with internal septations and
echoes of varying density. Differential
diagnosis must include a malignant tumour.
42. • Fig. 34.39 Huge pleural effusion in a young
girl. Aspiration revealed heavily blood-stained
fluid with multiple macrophages typical of
pleural endometriosis.
43. • Fig. 34.40 TAS. Endometriosis in the bladder
(cursors). Arrowheads mark position of the
uterus.
44. • Fig. 34.41 TAS. Acute pelvic infection with a
thick-walled tuboovarian abscess (arrow) and
free pus in the pouch of Douglas (arrowhead).
45. • Fig. 34.42 EVS. Large thin-walled chronic
hydrosalpinx.
46. • Fig. 34.43 TAS. Complex pelvic mass behind
the uterus (arrowheads) due to peritoneal
mesothelioma. Note multiple internal
septations and how the mass conforms to the
shape of the pelvis.
47. • Fig. 34.44 TAS. Adnexal cyst with one solid area
and some fine internal echoes suggestive of a
serous cystadenocarcinoma. Histology confirmed
a borderline malignant tumour.
48. • Fig. 34.45 TAS. Malignant adnexa, ) st with
internal echoes and irregularly thickened wall
(arrowhead).
49. • Fig. 34.46 TAS. Solid tumour mass (white
arrowheads) surrounding the posterior aspect
of the uterus (black arrows).
50. • Fig. 34.47 TAS. Benign mucinous
cystadenoma showing the typical
multiloculated appearance—impossible to
differentiate from a malignant tumour.
51. • Fig. 34.48 TAS. Solid ovarian mass with a
thickened endometrium (arrowheads) in a
postmenopausal patient. Histology revealed a
benign functioning thecoma.
52. • Fig. 34.49 EVS. Ovarian fibroma.
Homogeneous solid mass (arrows) arising
from the ovary (arrowheads).
53. • Fig. 34.50 TAS. Typical dermoid with a
floating echogenic area with acoustic
shadowing due to fat, with or without
calcification.
54. • Fig. 34.51 TAS. Dermoid cyst in a pregnant
patient. Note the echogenic nodule (arrows)
and dense acoustic shadowing (arrowheads).
55. • Fig. 34.52 EVS. Solid-appearing dermoid cyst.
Note the thick septum and two nodules
(arrows and arrowheads) casting shadows.
56. • Fig. 34.53 EVS. Echogenic dermoid cyst (arrows).
Note how the mass mimics a loop of bowel. The
remainder of the ovary (arrowheads) is seen.
57. • Fig. 34.54 TAS. Bilateral adnexal masses due
to ovarian metastases. Note predominantly
cystic mass on the right and partly solid mass
on the left.
59. • Fig. 34.56 TAS. Metastatic ovarian carcinoma
showing serosal tumour (arrowheads) around
a loop of bowel (arrow).
60. • Fig. 34.57 TAS. Large malignant germ cell
tumour in a 25-year-old. Doppler shows
typical low impedance flow with RI of 0.5.
61. • Fig. 34.58 EVS. Ovarian cyst with nodule in a 65-
year-old. Doppler shows low impedance flow (RI
0.50) suggestive of a malignant tumour. Histology
revealed a benign cystadenofibroma with a
Brenner tumour. No evidence of malignancy.
62. • Fig. 34.59 HyCoSy. Contrast (Echovist) is seen
outlining the cavity and entering the fallopian
tube (arrows).
63. • Fig. 34.60 HyCoSy. Echovist outlines a fibroid
polyp (arrows) in the uterine cavity.
64. • Fig. 34.61 Dermoid cyst. Note calcification
and teeth with a fat—fluid level (arrow).
65. • Fig. 34.62 Barium enemas. (A) Serosal
metastases from ovarian carcinoma. (B) Short
smooth stricture due to endometriosis
(arrowheads). Note the puckering of the
serosal due to adhesion (arrow).
66. • Fig. 34.63 HSG. Normal cavity. Both tubes visible
with regular mucosal folds and free peritoneal
spill. Note how the contrast flows around loops of
bowel (arrows).
67. • Fig. 34.64 HSG. Venous intravasation. The
myometrial plexus is shown with drainage
into the ovarian veins (arrowheads).
Peritoneal spill is also seen.
68. • Fig. 34.65 Important congenital abnormalities
of the uterus.
69. • Fig. 34.65 Important congenital abnormalities
of the uterus.
70. • Fig. 34.66 HSG. Uterus bicornis bicollis. Note
the completely separate cervical canals and
uterine horns, both of which have patent
tubes.
71. • Fig. 34.67 HSG. Bifid uterine cavity.
Impossible to be sure if this is bicornuate or
septate.
72. • Fig. 34.68 HSG. Unicornuate uterus. No
evidence of a rudimentary horn.
73. • Fig. 34.69 HSG. Filling defect due to
submucous fibroid.
74. • Fig. 34.70 HSG. Cavity and right fallopian tube
being distorted by large mural fibroid. Note
small calcified fibroid on the left (arrows).
76. • Fig. 34.72 HSG. Polypoid endometrium
causing multiple filling defects (arrows) only
seen on the early filling film.
77. • Fig. 34.73 HSG. Linear filling defects in the
uterine cavity due to adhesions.
78. • Fig. 34.74 HSG. Severe Asherman's syndrome
with complete obliteration of the uterine
cavity.
79. • Fig. 34.75 HSG. Tuberculous endometritis
leading to an irregular T shaped uterine
cavity.
80. • Fig. 34.76 HSG. Enlarged uterus with multiple
diverticular-like projections of contrast into
the myometrium typical of adenomyosis.
81. • Fig. 34.77 HSG. Normal right tube but a large
left hydrosalpinx. Note the mucosal folds on
the left have been obliterated and there is no
distal spill.
82. • Fig. 34.78 HSG. Salpingitis isthmica nodosa
(arrows). The right tube is patent but the left
tube is very irregular and beaded and
terminates in a hydrosalpinx (arrowhead).
84. • Fig. 34.80 Selective salpingography. 5F
catheter and wire manipulated into the right
uterine cornua. Subsequent injection of
contrast shows tubal patency with free
peritoneal spill.
85. • Fig. 34.81 CT. Bulky uterus with low-density
areas due to fibroids. One small fleck of
calcification.
86. • Fig. 34.82 CT. Bulky mildly heterogeneous
uterus with posterior displacement of the
cavity due to adenomyosis rather than
fibroids.
87. • Fig. 34.83 CT. Small adnexal cyst (arrow) in
postmenopausal patient. EVS confirmed a
small simple cyst.
88. • Fig. 34.84 CT. Complex mass in the pelvis typical of a
dermoid cyst (arrows). The mass is of mixed
attenuation but contains a large amount of fat. It has a
calcified rim and a dense area of calcification
(arrowheads) inferolaterally due to a tooth.
89. • Fig. 34.85 CT. Bilateral cystic adnexal masses.
Note the tiny gas bubble (arrow) seen in one
of the masses. Laparoscopy confirmed
bilateral hydrosalpinges with chronic infection.
91. • Fig. 34.87 Patient with a history of recurrent
very heavy vaginal bleeding. Selective internal
iliac artery injection shows an abnormal stellate
collection of vessels on the right. Embolisation
was performed, with good symptomatic relief.
92. • Fig. 34.88 Normal uterus on a sagittal T 2 -
weighted spin-echo (TSE 3500/100) image with
normal zonal anatomy of central high-signal
endometrium (e), the junctional zone (j) and the
outer myometrium (m). b = urine-filled bladder.
93. • Fig. 34.89 Normal zonal anatomy of the cervix
on a transverse T2 -weighted spin-echo (TSE
3500/100) image. b = bladder; s = cervical
stroma; straight arrow = cervical mucus and
epithelium.
94. • Fig. 34.90 Nabothian cysts (curved arrow)
within the cervix on a fat suppressed
transverse T2 -weighted spin-echo (FSE
3500/100) image.
95. • Fig. 34.91 An IUCD (arrow) within the uterus
(u) on a transverse fat suppressed T2-
weighted spin-echo (FSE 3500/100) image. f =
free fluid in the sacral cul de sac.
96. • Fig. 34.92 (A,B) Uterine didelphys showing two
separate uteri and cervices (arrows) are
demonstrated on transverse T2-weighted spin-
echo (FSE 3500/100) images. Note the normal left
ovary (o).
97. • Fig. 34.93 Multiple leiomyomas (I) on (A) sagittal and
(B) T2-weighted spin-echo (FSE 3500/100) images with
a large cervical intramural leiomyoma (c) and smaller
intramural tumours (e). There is a degenerating serosal
leiomyoma (d) and a smaller serosal leiomyoma (s)
adjacent to a loculated cystic collection due to an
associated hydrosalpinx (h). b = bladder.
98. • Fig. 34.94 Endometrioma deposit (arrow) within the
bladder wall on (A) coronal T i -weighted (SE 650/25)
and (B) corona! T 2 -weighted spin-echo (TSE
3500/100) images. Note the areas of high signal within
the superficial margin of the deposit due to
haemorrhage in (A), and the low signal on the T2 -
weighted in (B). b = bladder; u = uterus.
99. • Fig. 34.95 Endometriosis on a transverse T2-weighted
spin-echo (TSE 3500/100) image showing multiple
fluid–fluid levels from haemorrhagic contents within
multiloculated cysts filling the pelvis. There is dilatation
of the right ureter (arrow).
100. • Fig. 34.96 Focal adenomyosis (arrow) on (A)
coronal and (B) sagittal T2- weighted spin-echo
(TSE 3500/100) images showing focal low-signal
thickening of the junctional zone in (A)
undergoing haemorrhage (arrowed in (B) a year
later. b = bladder; e = intramural leiomyoma.
101. • Fig. 34.97 Diffuse adenomyosis on sagittal T2-
weighted spin-echo (TSE 3500/100) image
showing diffuse irregular low-signal thickening
of the junctional zone. b = bladder.
102. • Fig. 34.98 Carcinoma of the cervix (stage IB2)
showing exophytic tumour (arrows) within the
vaginal canal on sagittal T 2 -weighted spin-echo
(TSE 3500/100) image. Note the intact low-signal
vaginal wall. b = bladder.
103. • Fig. 34.99 Large cervical carcinoma (arrow) infiltrating into
the bladder (b) with a separate tumour nodule in the
posterior fornix (arrowhead) on a sagittal T2 -weighted
spin-echo (FSE 3000/100) image. Note the endometrial
obstruction (e). (Courtesy of Dr J. M. Hawnaur, Department
of Diagnostic Radiology, University of Manchester.)
104. • Fig. 34.100 Bulky exophytic cervical carcinoma confined
within the cervix on a sagittal T 2 -weighted spin-echo (TSE
5041/132) image. The low signal vaginal wall remains intact
apart from an area of tumour infiltration posteriorly
(arrow). Within the tumour in the anterior fornix there is an
area of necrosis. b = bladder. (Courtesy of Dr R. J. Johnson,
Christie Hospital.)
105. • Fig. 34.101 Carcinoma of the cervix (stage IIB)
showing tumour (t) within the parametrium (arrows)
on transverse T 2 -weighted spin-echo (FSE 3500/100)
image. Note the loss of the normal low signal from the
cervical stroma. b = bladder.
106. • Fig. 34.102 Bulky carcinoma of the cervix extending
into the body of the uterus, lower third of the vagina
(small arrows) and bladder (open arrow) on a sagittal T
2 -weighted spin-echo (TSE 5041/132) image. (Courtesy
of Dr R. J. Johnson, Christie Hospital.)
107. • Fig. 34.103 Tumour (t) infiltrating the
parametrium and left iliacus muscle (i), with left-
sided involved lymph nodes (n) and a right
ovarian metastasis (o) on a transverse T 2 -
weighted spin-echo (TSE 3500/100) image. b =
bladder.
108. • Fig. 34.104 Cervical carcinoma (t) extending into the
parametrium producing left hydronephrosis (straight
arrow) and extending posteriorly through the perirectal
fascia into the rectal mucosa (curved arrow) on a transverse
T2 -weighted spin-echo (TSE 5041 /1 32) image. b = bladder
(Courtesy of Dr R.J. Johnson, Christie Hospital.)
109. • Fig. 34.105 Recurrent carcinoma of the cervix (t)
infiltrating into the parametrium and right
levator ani on a transverse T 2 -weighted spin-
echo (TSE 5041/132) image. Note the low-signal
vaginal wall (arrow). b = bladder, r = rectum.
(Courtesy of Dr R. J. Johnson, Christie Hospital.)
110. • Fig. 34.106 Carcinoma of the cervix (t)
infiltrating through the bladder wall (arrow)
on a transverse T 2 -weighted spin-echo (TSE
3500/100) image. b = bladder.
111. • Fig. 34.107 Extensive recurrent cervical carcinoma (t) following a hysterectomy on (A) selected transverse T 2
-weighted spin-echo (TSE 3500/100) images, and (B) coronal T 2 -weighted spin-echo (TSE 3500/100) fat-
suppressed image. There is a large tumour recurrence infiltrating through the lower two-thirds of the vagina
into the pelvic floor and in the bladder wall (open arrow), with separate tumour nodules in the right ischial
rectal fossa (straight arrow) and left parametrium. There is bilateral inguinal lymphadenopathy (small arrows).
Note the mass of higher signal than tumour in the left adnexa from the native ovary. b = bladder.
112. • Fig. 34.107 Extensive recurrent cervical carcinoma (t) following a hysterectomy
on (A) selected transverse T 2 -weighted spin-echo (TSE 3500/100) images, and
(B) coronal T 2 -weighted spin-echo (TSE 3500/100) fat-suppressed image. There is
a large tumour recurrence infiltrating through the lower two-thirds of the vagina
into the pelvic floor and in the bladder wall (open arrow), with separate tumour
nodules in the right ischial rectal fossa (straight arrow) and left parametrium.
There is bilateral inguinal lymphadenopathy (small arrows). Note the mass of
higher signal than tumour in the left adnexa from the native ovary. b = bladder.
113. • Fig. 34.108 Carcinoma of the cervix (straight arrows) on sagittal T
2 -weighted spin echo (SE 1500/80) (A) before treatment, (B) 6
weeks, and (C) 6 months after radiotherapy. Note the rapid
reduction in size of the tumour between (A) and (B). The small area
of high signal in the cervix in (C) is due to either residual tumour or
post-treatment change. Note the low-signal area in the uterus due
to a non-degenerating leiomyoma (curved arrow), and the high
mucosal signal in the posterior wall of the bladder (b) from
radiotherapy change in (B) and (C).
114. • Fig. 34.108 Carcinoma of the cervix (straight arrows) on sagittal T
2 -weighted spin echo (SE 1500/80) (A) before treatment, (B) 6
weeks, and (C) 6 months after radiotherapy. Note the rapid
reduction in size of the tumour between (A) and (B). The small area
of high signal in the cervix in (C) is due to either residual tumour or
post-treatment change. Note the low-signal area in the uterus due
to a non-degenerating leiomyoma (curved arrow), and the high
mucosal signal in the posterior wall of the bladder (b) from
radiotherapy change in (B) and (C).
115. • Fig. 34.109 Extensive radiation change involving the bladder, vagina,
rectum and bowel loops on (A) sagittal T2-weighted (SE 1 500/80) and (B)
transverse T 1 -weighted (SE 800/40) images. In (A) the bladder (b) has a
thickened wall with a high-signal-intensity mucosa around the posterior
wall. The uterus (u) is enlarged and the vagina (arrows), rectosigmoid (r),
and adjacent small bowel loops (I) show thickened walls with high signal.
No evidence of recurrence of cervical carcinoma, which was confirmed on
histological review. The high signal from the sacrum and L5 vertebra is due
to radiation-induced fatty infiltration of the marrow spaces. The area of
signal void within the vagina in (A) is due to a tampon in situ.
116. • Fig. 34.110 Stage IC endometrial carcinoma
(e) on a sagittal T2 3500/100) image. b =
bladder. -weighted spin-echo (TSE
117. • Fig. 34.111 Endometrial carcinoma (e) on a
sagittal T 2 -weighted spinecho (TSE
3500/100) image with associated lymph node
involvement (demonstrated on other sections)
making this a stage IIIC tumour. b = bladder.
118. • Fig. 34.112 Bilateral cystic ovaries (o) in a 25-year-old on a
coronal fat saturation T2 -weighted spin-echo (TSE
3500/100) image showing a low signal haemorrhagic right
ovarian cyst (large arrow—probably a corpus luteum cyst)
with some surrounding free intraperitoneal fluid (small
arrows). r = rectum; u = uterus.
119. • Fig. 34.113 Multiloculated thin-walled
haemorrhagic benign ovarian cysts (c)
showing fluid–fluid levels on a transverse T 2 -
weighted spin-echo (SE 2000/120) image.
There is a coincidental uterine leiomyoma (I).
120. • Fig. 34.114 Large left adnexal mass (d) due to an ovarian dermoid
displacing the uterus which contains a coincident subserosal
leiomyoma (I) on (A) coronal T 1 -weighted (SE 720/25) and (B)
transverse T 2 -weighted spin echo (TSE 2000/80) images. The
dermoid cyst has solid and cystic components with some areas of
intermediate–high signal noted in (A).
121. • Fig. 34.115 Dermoid cyst (arrows) showing a
unilocular mass with a nodule within high-signal fat on
(A) coronal T 1 -weighted spin-echo (TSE 700/12) image
and (B) sagittal T2 -weighted spin-echo (TSE 3500/100)
image. A fat-suppressed sequence (not shown) was
also performed to confirm the fat contents of the cyst.
b = bladder.
122. • Fig. 34.116 Complex large left adnexal mass with solid and cystic
components (arrows) compressing and displacing the uterus on
transverse T2 - weighted spin-echo (TSE 51 36/1 32) image. Note
that there is distension of the endometrial cavity with intermediate
to high signal due to a coexisting endometrial tumour (e).
Endometrioid carcinoma of the ovary is associated in approximately
a third of cases with endometrioid carcinoma of the uterus.
(Courtesy of Dr R. J. Johnson, Christie Hospital.)
123. • Fig. 34.117 (A) Mutinous cystadenocarcinoma of the ovary producing a
large mass, with mixed contents, filling the pelvis on a transverse T2-
weighted (FSE 3000/100) image. The area of signal void within the tumour
is due to either blood products or mucin. (Courtesy of Dr J. M. Hawnaur,
Department of Diagnostic Radiology, University of Manchester.) (B) Large
right ovarian inflammatory mass, proven actinomycosis (t) producing an
obstructive uropathy with dilatation of the right ureter (u) on a transverse
T 2-weighted spin echo (TSE 3500/100) image. Note the position of the
ureter to the adnexal mass, and the normal left ovary (o).