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7.3.2 Physiology
Anterior pituitary secrets the hormones under
the inuence of the hypothalamus. The main
hormones are growth hormone (GH), adrenocorticotrophic hormone (ACTH), thyroid-stimulating hormone (TSH), prolactin (PRL),
gonadotropins (Luteinising hormone, LH and
Follicular- stimulating hormone, FSH). Posterior
pituitary secrets oxytocin and vasopressin
(Figs.7.18 and 7.19).
The list of pituitary tumours is long and differential diagnosis of sellar lesions is listed in
Table7.1.
(A) Pituitary Adenoma
It is the most common type of pituitary
lesion. The classication of adenoma is
based on the size of the tumour and immunohistochemical expression (Table 7.2)
[28]. The incidence of incidentalomas is
10% [29, 30].
1. Non-functional Pituitary Adenoma
No hormone is secreted and symptoms
are usually due to pressure effects. The
Fig. 7.18 Blood supply—Hypothalamic—Pituitary axis
(1) anterior pituitary, (2) posterior pituitary, (3) superior
hypophyseal artery, (4) inferior hypophyseal artery, (5)
third ventricle, (6) neuroendocrine nuclei, (7) hypothalamus, (8) long portal vessels, (9) short portal vessels and
(10) hormone release
common clinical features include headache, visual disturbance, features of
hypopituitarism and hydrocephalus.
Indication of surgery in these patients is
to relieve and to prevent the mass effect
of the tumour and pituitary apoplexy
[
31]. As far as treatment is concerned,
surgery remains the mainstay with radiotherapy in recurrent and invasive cases.
2. Functional Pituitary Adenoma
The types of pituitary function adenoma
are based on the hormone secreted by
adenoma.
(i) Prolactinoma
This is the most common type
(40%) of functional adenoma [28]
with clinical features depending
upon the gender. Females present as
secondary oligomenorrhoea and/or
galactorrhoea whereas males present with galactorrhoea, impotence,
headache and visual disturbance.
This tumour is unique because the
medical treatment is the mainstay in
more than 90% of the patients and
includes dopamine agonists like
bromocriptine and cabergoline.
Surgical management, although
rarely required, has specic indications like failure of medical treatment, patient preference, pituitary
apoplexy, CSF leak during medical
therapy [
32] and pregnancy-related
issues [33].
(ii) Acromegaly
These are the growth hormonesecreting tumours and about 10% of
these tumours occur before adulthood and lead to gigantism. Clinical
features include enlarged nose,
chin, hands and feet and endocrine
abnormalities include increased
GH, insulin-like growth factor (IGF
I) levels in serum. The morbidity
and mortality in this subset of
tumours is related to cardiovascular
complications. As far as the treatment is concerned, surgery remains
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ACTH
ADRENAL
CORTISOL
HYPOTHLAMUS
PITUTARY
TSH
THYROID
T3,T4
TESTOSTERONE
INHIBIN
CRH
LH FSH PRL
TESTES
TSH
OVARY BREAST
PROGESTERONE
ESTRADIOL
INHIBIN
GnRH
LACTATION
GHRH
SRIF
LIVER
IGF-1
DOPAMIN
ADH
KIDNEY
WATER
RESOPTION
OXYTOCIN
GH
OTHER
ORGANS
LINEAR
GROWTH
Fig. 7.19 Hypothalamic pituitary axis—regulation of hormone secretion
Table 7.1
Differential diagnosis of sellar lesions
Tumours Pituitary adenoma
Craniopharyngioma
Meningioma
Glioma
Chordoma
Lymphoma
Metastasis
Cyst Rathke’s cyst
Dermoid cyst
Inammatory
conditions
Bacterial Abscess
Tuberculosis
Table 7.2 Classication of pituitary adenoma
Based on size Based on character
Microadenoma
(<1cm)
• Enclosed
• Invasive
Macroadenoma
(>1cm)
• Enclosed
• Invasive
• Expanding
Sarcoidosis
Langerhans cell
histiocytosis
Hypophysitis
Others Pituitary apoplexy
Mesoadenoma
(1cm)
Hypothalamus hamartoma
ICA aneurysms
Non-functional
Clinically no function
(hypopituitarism due to pressure)
Functional
• Prolactinoma (Prolactin)
• Acromegaly (GH)
• Cushing disease (ACTH)
• Gonadotropin-producing
adenoma (LH, FSH)
• Thyrotropin-producing
adenoma (TSH)
• Mixed (GH with PRL)
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the mainstay with medical management aiming at correcting the hormonal abnormalities. The medical
agents include somatostatin analogue, dopamine agonist and GH
receptor antagonist. Radiotherapy is
reserved for invasive and recurrent
cases [34].
(iii) Cushing Disease
These tumours are usually ACTHsecreting microadenoma and have
pronounced clinical features usually
secondary to endocrine disturbances.
These include truncal obesity, hypertension, hirsutism, glycosuria, osteoporosis and psychosis. Surgery
remains the mainstay of treatment
with medical therapy aiming to correct the endocrine imbalances. In
rare cases, radiotherapy and bilateral
adrenalectomy have also been used
[35].
(iv) Gonadotropin-Secreting Adenoma
These are LH- and FSH-secreting
tumours and their symptoms are
usually due to mass effects; hence,
surgery is the main choice of
treatment.
(v) Thyrotropin-Secreting Tumours
These tumours secrete TSH and
patients usually present with central
hyperthyroidism features (palpitation, tremors, neck swelling, weight
loss, sweating, etc.). Treatment is
medical with somatostatin analogue
if compressive effects are not prominent; otherwise, surgical removal
of the tumour along with medical
therapy must be taken into
consideration.
(B) Pituitary Apoplexy
It is the sudden pituitary haemorrhage or
haemorrhage in adenomas and usually presents with dramatic clinical features like sudden visual loss, headache and vomiting.
Treatment is surgical removal of the tumour
with evacuation of haematoma in order to
relieve the pressure.
Preoperative Work-Up
Apart from relevant history, e.g. nasal surgery
and co-morbid conditions, one should look
for features of various endocrine conditions
like Cushing, acromegaly, hyperthyroidism
and hypopituitarism. Special examination
includes ophthalmological work-up (visual
acuity, visual eld and proptosis evaluation),
neurologic examination (e.g. cranial III, IV, V
and VI), endocrine assessment (hormonal
assessment and electrolyte evaluation), nasal
endoscopic examination—to look for abnormal anatomy and adequacy for nasal septal
ap. Imaging studies include delayed postcontrast MRI, which is the modality of
choice. MRI helps in determining the extent
of tumour, cavernous sinus involvement, ICA
involvement (signal void in T2 MRI), identication of normal pituitary gland (neurohypophysis shows increased signal intensity in
T1 non- contrast) and optic chiasm. CT paranasal sinus must also be done as it helps in
surgical planning, anatomical study (sinuses,
skull base, optic nerve, Onodi cell) and also
helps in differential diagnosis (calcication in
craniopharyngioma).
Aims and Principles of Pituitary Surgery
They include elimination of mass effect, restoration of pituitary function, prevention of
recurrence, complete histopathological
diagnosis, and if possible, normalization of
hormonal production.
Operative Procedure
(i) Anaesthesia
General anaesthesia with orotracheal
intubation is standard. The anaesthetist
is requested for hypotensive anaesthesia (Mean Arterial Pressure between 60
and 80mmHg, Heart rate less than 70)
in order to get a clean surgical eld and
minimize the blood loss.
The patient is placed in a supine
position with 30° head up (reverse
Trendelenburg position) and ceftriaxone 2 g I.V. or clindamycin 600mg IV/
vancomycin 1 g iv in cases of beta-lactam allergy, is injected before starting
the surgery.
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(ii) Instruments and Equipment
A three-chip or preferably HD camera
with a large LED monitor of 20 inches
or larger (easier on the eyes) is required
for visualizing the structures clearly. A
complete Functional Endoscopic Sinus
Surgery set with various sized straight
and angled up-cut and down-cut rongeurs along with high-speed drill is
essential. Among the optional instruments are microdebrider, plasma ablation and doppler for identication of
para-sellar carotid artery. Neuronavigation, if available, is recommended in cases of extensive tumour
with distorted anatomy or revision surgery to identify the landmarks.
(iii) Surgical Approaches
The surgical approaches can be either
transseptal, trans-ethmoidal or transnasal [36–38]. Endoscopic transnasal
trans-sphenoidal approach is usually
considered the standard approach for
pituitary surgery because of the following advantages: good panoramic view,
preservation of normal function,
reduced hospital stays and improved
patient outcome. The surgery can be
divided into the following steps:
• Position: The surgery is started with
the proper positioning of the patient.
We use a reverse Trendelenburg
position.
• Nasal phase: Nasal cavity is decongested with commercially available
sponges or by cotton pledgets
soaked in 1:10,000 Adrenaline. The
surgical corridor used is the space
between the middle turbinate and
nasal septum. Inferior turbinate is
out fractured to create space (not
always needed), the Middle turbinate is lateralized and the superior
turbinate is identied and gently lateralized to reveal the natural sphenoid ostia. Many times the sphenoid
ostia is oedematous and not clearly
visible, decongestion usually will
expose it. If a Hadad ap is planned,
then it has to be harvested before the
septectomy is done.
• Septal phase: Using the plasma
ablation, the mucosa around the
ostia and the nasal septum is ablated
away and steps are repeated on the
opposite side. Septectomy is performed and the sphenoidal phase of
surgery is started.
• Sphenoidal phase: Sphenoid ostias are
widened on both sides using a rongeur
and the keel of sphenoid drilled away
using a high-speed cutting burr. Any
bleeding from the bone is taken care of
with a diamond burr (Figs. 7.20 and
7.21). With the sphenoid sinus wide
open, the mucosa from the sinus is elevated and removed completely. After
this, the intersinus septum is drilled
away or cut with a through-cut. The
bone over the sella is drilled using a diamond burr; if the bone is thick, a cutting
burr is used. The thin bone is then taken
away with a rongeur and the dura is
exposed.
• Sellar phase: Using the coagulation
mode of the plasma ablator, the dura
Fig. 7.20 Sphenoid ostia identied and area being
plasma ablated
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is coagulated and at this point, it
becomes a four-hand technique with
the neurosurgeon joining the surgery.
• Neurosurgical removal of tumour:
An incision is made over the dura and
using saline, hydro- dissection is
done. If the tumour is soft and suckable, a major part of it just bulges out
with hydro- dissection. Biopsy is
taken and using curettes and suction,
the neurosurgeon clears the tumour.
Suprasellar and lateral extensions
require angled endoscopes (30° or
45°). After ensuring complete tumour
removal and examination of the sella,
the defect is repaired.
• Reconstruction of the defect: The
fat is wrapped in oxidized cellulose
polymer. We have found that this
makes it easier to manipulate the
fat. A fascia lata graft is used by
overlay, underlay or interlay fashion and brin glue is applied over
it. A small piece of gel foam is then
applied over the glue. No nasal
packs are used. Readers can access
the author’s surgical video via the
following link: https://youtu.
be/L- YEssDFGGQ
7.3.3 Postoperative Care
The choice of antibiotics and analgesics is
depending upon the institution’s preference. The
patient should spend his rst 24–48h in an ICU
with physicians experienced in monitoring
important signs like CSF leak, visual disturbance,
nasal bleed, etc. The ICU team should be able to
manage possible conditions like diabetes insipidus and meningitis. Routine advise includes bed
rest, head-end elevation and stool softener along
with copious saline drops to prevent crusting.
The patient should be advised strict follow-up to
prevent crusting.
7.3.4 Pearls ofPituitary Surgery
Superior turbinate, superior margin of choana are
key landmarks for sphenoidal ostium identication. Adequate removal of the anterior wall of
sphenoid is essential for good visualization of
sella. Recognition of medial and lateral opticocarotid recesses are important. The need for vascularized nasoseptal ap is to be considered prior to
sphenoidotomy. The drilling of tuberculum and
planum is considered in suprasellar extension. The
delineation of carotid in cavernous sinus extension
is important and attention to superior and inferior
inter-cavernous sinus is important.
Fig. 7.21 Owls eye appearance, the ostia have been widened and septectomy done
7.4 Part D: Open Techniques
forNose andParanasal
Sinuses
The surgical approaches for the nose and paranasal sinuses range from endoscopic to conventional open techniques. The contemporary
indications for endoscopic approaches to the
paranasal sinuses and skull base have been
expanded making conventional open techniques
less frequent [39]. Absolute indications necessitating either a transfacial or a transpalatal incision include skin and subcutaneous tissue
invasion, extensive involvement of the orbital fat,
extraocular muscles and eyelid skin and palatal
involvement. Traditionally, intracranial exten-
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sion, cavernous sinus involvement [40] and
extension beyond the mid-pupillary line were
considered to preclude endoscopic approaches.
With advancements in neuro-navigation and
endoscopic surgical armamentarium, properly
selected cases with the above-mentioned disease
extension can be dealt without resorting to conventional open approaches. Open approaches in
this chapter have been classied into bone and
soft tissue approaches. Soft tissue approaches
and incisions like the Moure’s incision with lateral rhinotomy also serve as a precursor for bony
approaches like the medial maxillectomy. Bony
approaches can further be classied into midline,
paramedian and lateral approaches based on the
trajectory to the skull base. Strictly midline
approaches include transpalatal, lateral rhinotomy, medial maxillectomy and Le Fort’s
Osteotomy approach. Paramedian approaches
additionally target the infratemporal fossa with
the maxillary swing being the best example.
Lateral approach to the paranasal sinus and the
skull base as in the case of a preauricular subtemporal approach provides excellent visualization
of the lateral part of the infratemporal fossa,
para-sellar, cavernous sinus and lesions located
lateral to the cavernous internal carotid artery.
Craniofacial resection pertains to a combination
of transfacial or transpalatal approach to the paranasal sinus and a bicoronal incision with frontal
craniotomy for the intracranial component.
Choosing the best approach requires detailed preoperative radiological assessment and an understanding of tumour biology.
7.4.1 Indications forOpen
Approaches
These vary for inammatory disease and for neoplastic disease. For inammatory disease, mere
drainage of sinus contents and partial removal of
polypoid mucosa is appropriate and the contraindications to endoscopic approaches are few.
Frontal sinus disease extending beyond the midpupillary line can however be a relative contraindication as it can be inaccessible even with the
modied Lothrop technique. The prime focus of
this chapter is on neoplastic disease (benign or
malignant), the indications for open approaches
may be listed as the following:
•
Lesion extending beyond mid-pupillary line
• Skin involvement
• Extensive involvement of orbital fat, extraocular muscles and skin of the eyelid
• Involvement of the bone of the hard palate or
paranasal sinuses
• Signicant intracranial extension
7.4.2 Relative Contraindications
forSurgical Resection
ofNose/Paranasal Sinus
Tumours
Surgical resection with open technique with or
without endoscopic guidance can be attempted
but resection may not offer oncological clearance
of the disease [41]:
• Orbital apex involvement
• Infratemporal fossa involvement
• Erosion of pterygoid plates
• Cavernous sinus involvement
• Intradural/brain parenchymal involvement
• Involvement of nasopharynx and sphenoid
sinus
• Cranial nerve involvement other than I, II and
infraorbital nerve
• Encasement of internal carotid artery
Tumour extension to the above-mentioned
sites are technically resectable. Resection can be
attempted in case of benign tumours like nasopharyngeal angiobroma and inverted papilloma,
and similarly, low-grade sinonasal malignancies
like olfactory neuroblastoma (Hyams grade 1 and
2), epithelial–myoepithelial carcinoma, bipheno-
typic sinonasal sarcoma and adenoid cystic carcinoma [42]. It is to be noted that although adenoid
cystic carcinoma is a high-grade malignancy, it
has a protracted course with disease recurrence
and metastasis occurring after as long as 10years,
justifying the radical resection. Moreover, many
of these tumours are relatively non-responsive to
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radiation or chemotherapy. Therefore, radical
surgical excision followed by adjuvant therapy
offers the best chance of cure [43, 44].
7.4.3 Preoperative Work-Up
Before embarking on the surgical aspects of
treating sinonasal tumours, detailed preoperative
evaluation is of paramount importance. This
broadly includes radiologically mapping the
tumour followed by biopsy from representative
areas and screening for distant metastasis in case
of malignant tumours:
• Contrast-enhanced computed tomography
(CECT) should preferably be high-resolution 1mm cuts in the axial, coronal and sagittal planes. This provides information with
regard to bony involvement, intraorbital
extension, skull base erosion, major vessel
encasement.
• MRI provides information complimentary to
that of CECT with better soft tissue delineation. Hyperintense signal in any of the paranasal sinuses on T2 will differentiate
accumulated secretions from tumour. Invasion
of periorbita can be identied on T1-weighted
contrast sequences. Fat suppression allows
one to establish orbital fat involvement. This
facilitates preoperative decision-making with
regard to management of the orbit. Perineural
invasion can be inferred from a widened or
destroyed of neural foramina on a CT scan.
This can be conrmed on fat-suppressed
contrast- enhanced T1-weighted sequences as
enhancement along the course of the nerve or
atrophy of the muscles seen as hyperintensity
on T2-weighted sequences. MRI provides
detailed information with regard to the extent
of intracranial invasion. Extensive intraparenchymal invasion with surrounding oedema
usually precludes curative-intent treatment.
• Histopathological information is obtained by
means of an endoscopic biopsy. Radiology
should precede biopsy as this helps to undertake a directed biopsy, and also the tissue
oedema consequent to a biopsy may lead to
overestimation of tumour extent if radiology
is undertaken after. Open biopsy or sublabial
biopsy should be avoided as this may lead to
tumour seeding in the biopsy tract.
• Preoperative digital subtraction angiography
with or without embolization can be considered for vascular lesions (angiobroma,
hemangiopericytoma and vasoformative
tumours). This is also indicated in cases where
radiology shows encasement, narrowing or
irregularity of the internal carotid artery.
Information gathered from DSA and cerebral
cross-circulation will guide the management
of carotid artery involvement.
7.4.4 Classication ofApproaches
toNose andPNS
1. Soft Tissue Approaches (Surgical Incisions
Pertaining to the Nose and PNS) (Fig. 7.22)
• Moure’s Lateral Rhinotomy Incision
• Modied Moure’s incision.
• Weber–Ferguson incision.
• Modied Weber–Ferguson incision.
• Lynch–Howarth extension to Moure’s
incision.
• Weber–Ferguson with subcilliary
Dieffenbach Extension.
• Midfacial degloving.
• *Classical Moure’s and Weber–Ferguson
incisions provide excellent exposure but a
facial scar. Modications were introduced
to incorporate the concept of nasal and
facial aesthetic subunits.
• *Lip-split in a Weber–Ferguson incision
can be avoided in case of small tumours of
the lateral wall of the nasal cavity.
2. Bony Approaches:
• Maxillary swing
• Le Fort I osteotomy
• Transpalatal Approach
• Denker’s Approach
• Facial Translocation
7.4.5 Soft Tissue Approaches
1. Moure’s Lateral Rhinotomy incision is use-
ful for excision of tumours located in the
nasal cavity, maxillary sinus, ethmoid sinus
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P. Mittal et al.
Fig. 7.22 Surgical incisions pertaining to the nose and
PNS. (a) Weber–Ferguson–Longmire incision, (b) lateral
rhinotomy, lateral rhinotomy with lip splitting incision,
and orbit. Lynch–Howarth extension is helpful to access the frontal sinus. Weber–
Ferguson with or without lip-split provides
access to the lateral extension of the tumour
to the pterygopalatine fossa or the infratemporal fossa. Soft tissue approaches can be
part of more extensive procedures like
medial maxillectomy, orbital exenteration
and craniofacial resection
Limitations
The lateral rhinotomy approach is best suited
for midline tumours with minimal paramedian extension. Therefore, exposure to the
contralateral side or infratemporal fossa
extension form an important limitation of this
approach.
Technique
After making the incision, the ap is elevated
in a subperiosteal plane. Close to the orbit, the
ap is elevated supercial to the orbicularis
oculi muscle. This is done to prevent ectropion. Lateral limit of dissection for Moure’s
Lateral Rhinotomy approach is the infraorbital foramen and the nerve. Modications
can be made to this step to include skin or
subcutaneous tissue if involved by the disease
modied lateral rhinotomy, Weber–Ferguson–Longmire
with subcilliary Dieffenbach Extension (Courtesy—Dr.
Harsha Yadav, JR, ENT, AIIMS, New Delhi, India)
process. Entry into the nasal cavity is facilitated by the use of a Kerrison rongeur to
remove the bone at the naso maxillary suture
line. Soft tissue connecting the nasal mucosa
to the vestibule can be divided at the pyriform
aperture to complete exposure.
Complications:
•
Bleeding and haematoma can occur from
the external carotid system, mainly the
internal maxillary artery. This complication
can be minimized by either preoperative
embolization or by identifying and ligating
the internal maxillary artery preemptively.
Suture line dehiscence can occur especially
•
if acute angulations are created while
designing the incision. One should always
place incisions on a bony framework especially near the medial canthus.
2. Midfacial Degloving (Figs. 7.14 and 7.23)
This approach provides excellent exposure
without the need for a facial incision. With
regard to the indications, it serves as an alternative to the lateral rhinotomy. Additionally,
tumours crossing the midline can also be
approached. This technique can only be
extended to lesions situated inferior to the infra-
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Fig. 7.23 Midfacial degloving (Courtesy—Dr. Harsha
Yadav (JR (ENT), AIIMS, New Delhi)
orbital foramen. Moreover, skin and orbital
invasion are not suitable for this technique.
Technique
Midfacial degloving entails elevation of the
midface in a subperiosteal plane. To accomplish this, a sublabial incision is made from
one maxillary tuberosity to the other. To
elevate the cartilaginous external nasal
framework off the pyriform aperture, a complete transxion incision and an intercartilaginous incision is made. Once the vestibule
is freed from the pyriform aperture, the ap
elevation is completed till the infraorbital
foramen.
Complications
A complication unique to this approach is
vestibular stenosis.
7.4.6 Bony Approaches
1. Maxillary Swing (Fig. 7.24, Fig. 6.16 (Chap. 6))
Displacing the maxilla anteriorly as an osteoplastic ap with the overlying skin and soft
tissue based on the greater palatine artery
exposes the skull base posterior to the posterior wall of the maxilla.
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Indications
Tumour extending to the following anatomical
sites can be accessed using maxillary swing:
Nasopharynx
•
• Infratemporal fossa
• Sphenoid sinus
• Pterygoid plates
• Cavernous sinus, clivus and foramen
magnum
Limitations
This approach is ideally suited for midline and
paramedian lesions. Therefore, one should not
consider maxillary swing in case of tumour
extension posterior to the carotid artery or
extension to the contralateral skull base.
Technique
The soft tissue approach can either be a
Weber–Ferguson or a midfacial degloving.
One should be careful in not elevating beyond
what is required to place the osteotomies to
prevent devascularization of the osteoplastic
ap. Preplating is performed at the following
sites of osteotomy:
•
Frontal process of maxilla extending from
the pyriform aperture to the inferior orbital
ssure
• Zygomatic process of the maxilla to the
inferior orbital ssure
Palatal incision is the modied Owen’s
incision placed close to the alveolar process.
Mucoperiosteal ap is elevated based on the
contralateral greater palatine artery. Midline
osteotomy is performed over the hard palate.
The last osteotomy is placed between the
maxillary tuberosity and the attachment of
the pterygoid plates using a curved osteotome. After completion of the osteotomies,
the entire maxilla with the overlying skin and
soft tissue can be swung laterally exposing
the pterygomaxillary ssure and the infratemporal fossa.
Complications
Palatal stula: This complication can be
•
minimized by avoiding the superimposition of the mucosal and the hard palatal
incision. One way to go about this is the
modied Owen’s incision and placement
of a palatal prosthesis to keep the muco-
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a
Fig. 7.24 Left maxillary swing. (a) Miniplates are xed
at the site of osteotomies (Courtesy—Dr. Kuldeep Thakur,
MCh student (Head and Neck cancer), AIIMS, New
b
Infra temporal fossa
contents
Maxilla left
side
Delhi, India), (b) Maxilla swung on left side which allows
exposure of infratemporal fossa contents (Courtesy—Dr.
Harsha Yadav (JR (ENT), AIIMS, New Delhi)
Fig. 7.25 Le Fort I Osteotomy (Courtesy—Dr. Harsha Yadav (JR (ENT), AIIMS, New Delhi)
periosteal ap in close proximity to the
bone.
• Dental malocclusion: Preplating prior to
osteotomy helps in maintaining postoperative occlusion.
2. Le Fort I Osteotomy (Fig. 7.25)
Following a sublabial incision, a transverse
facial osteotomy is created along the lines of
Le Fort I fracture displacing the palate
inferiorly.
Indications
This is a strictly midline approach for selected
cases of nasopharyngeal angiobroma, clival
chordoma and nasopharyngeal carcinoma. If
combined with medial maxillectomy, it can
provide some paramedian extension also.
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