Download Pituitary Apoplexy

Pituitary Apoplexy
Jirasak P.
R2 MD
Historical Aspects
• 1898 Bailey –first description
• 1938 Sheehan – pituitary infarction and
panhypopituitarism after obstetrical hemorrhage
• 1950 Brougham – described 5 cases, recognized
and named clinical syndrome
Pituitary Apoplexy is defined clinically
– An acute clinical syndrome with the sudden
onset of:
•
•
•
•
•
Headache
Vomiting
Visual disturbances
Ophthalmoplegia
Alterations in the state of consciousness
– Occurs primarily in patients with pre-existing
pituitary adenomas, though also in nontumorous pituitaries
– Caused by extensive pituitary hemorrhage and
infarction
Subacute pituitary apoplexy
– Asymptomatic pituitary hemorrhage (and
infarction) with/without a pituitary tumor
Prevalence
• True prevalence uncertain – difficulty in
recognizing and diagnosing syndrome
• Surgical series: 10-15% adenomas show
hemorrhage-most silent
• Clinical syndrome estimated at 0.6-10% of
adenomas, based on symptoms and sudden
decrease or loss of pituitary function
• Non-adenomatous pituitaries: no data
Prevalence (2)
• Mean age: 47+15 years (range: 6-88)
• Males : females - 1.5 : 1
• About 2/3 of patients unaware of tumor at
time of apoplectic event
• Relationship to tumor type: no predilection
for cell type of adenoma; rare in
craniopharyngioma and hamartoma
Pathophysiology - theories
• Ischemic necrosis – Most tumors are not that big
• Ischemia and infarction 2o compression of stalk
and superior hypophyseal artery. Most vessels
from inferior hypophyseal artery
• Intrinsic vasculopathy of tumors. Pit. tumors >5x
more likely to bleed than other intracranial tumors
• Is primary event hemorrhagic or ischemic?
Hemorrhage seen in 100%, ischemic necrosis in
60%
Pathophysiology
• The anterior
pituitary gland is
perfused by its
portal venous system
• contributes to
frequency of
pituitary apoplexy
causing ischemia
and subsequent
necrosis
Signs and Symptoms
Variable, depending on which features of apoplexy
predominate
• Tumor expansion
- Upward
Visual fields and acuity
Hypothalamic dysfunction: temp, BP,
cardio-resp dysfunc., altered consciousness,
other neurol sx.
- Lateral
Ophthalmoplegia, V nerve dysfunction,
internal carotid artery compression
- Downward
Asymptomatic or epistaxis
Signs and Symptoms
• Subarachnoid bleeding
- Meningeal irritation and photophobia
- Aseptic meningitis
• Endocrine disturbances
Presenting Signs and Symptoms
(9 series over 30 year period; n = 272)
Headache
Visual field or acuity reduction
Ocular palsies
Nausea and vomiting
Meningismus
Decreased level of consciousness
Photophobia
Fever
Percent
85
63
49
42
17
16
10
7
- Evolution: few hours to 2 days
- Symptom severity proportional to tumor size
- Headaches generally precede ocular manifestations
Roleh et al,1993; Bills et al, 1993; Bonicki et al,1993; Randeva et al,1999
headache
• sudden and postulated to result from
stretching and irritation of the dura
mater
• irritation of the trigeminal nerve from
the expanding mass
• retro-orbital in location and may be
unilateral at onset, then becomes
generalized
Ocular involvement
• Visual acuity defects (52%) and visual field
defects (64%)
• upward expansion of the tumor, which
compresses the optic chiasm, optic tracts, or
optic nerve
• The classic visual field defect is a
bitemporal superior quadrantic defect
Ocular involvement
• Ocular paresis (78%)
• results from compression of the cavernous
sinus
• the oculomotor nerve (cranial nerve III) is
involved most commonly
• a unilateral dilated pupil, ptosis, and a globe
that is deviated inferiorly and laterally
• The sixth cranial nerve is least commonly
involved
Pituitary apoplexy can occur in
ectopic sites
• Hori examined normal adult brains at autopsy
and found ectopic pituitary cells in the leptomeninges of the peri-infundibular region in 75%.
• Ectopic pituitary adenomas commonly present
late because they displace rather than invade
vital nervous structures.
• They may be discovered only after the patient
has pituitary apoplexy.
• Only one case of an ectopic pituitary adenoma
that underwent apoplexy has been reported.
Endocrine Disturbances
• Sudden onset – features of adrenal insufficiency predominate
• Other abnormalities reflect underlying tumor: hormone
hypersecretion (GH, Prl, ACTH, TSH) and hypopituitarism
GH deficiency
Gonadal deficiency
Male
88%
Female
Adrenal insufficiency
Hypothyroidism
Hyperprolactinemia
52%
71%
46%
12%
Diabetes insipidus
2-3%
86%
- and - resolution of hypersecretory syndromes
Data from Veldhuis & Hammond, 1980 and Randeva et al, 1999
Precipitating Events
In half of cases (from series), no precipitating event
recorded
Publications in past 15 years (300)
• Irradiation – no evidence
• Sudden changes in BP or ICP, often associated with
procedures
- Angiography, LP, PEG, repetitive coughing, surgical
procedures - primarily cardiac (15)
• Head trauma (4)
• Anticoagulation and clotting disorders (5)
• Releasing hormones – for dx (31) and rx (6)
• Bromocriptine (8)
Sheehan syndrome
• pituitary apoplexy of a nontumorous gland
• presumably due to postpartum arterial
spasm of arterioles supplying the anterior
pituitary and its stalk.
• In 1937, Sheehan reported 11 cases of
women who died in the puerperium
• all of whom had necrosis of the anterior
pituitary gland (adenohypophysis).
• Nine of the 11 cases had severe hemorrhage
at delivery. The other 2 cases had no
hemorrhage but were gravely ill prior to
delivery
Sheehan syndrome
• Normally, the pituitary gland hypertrophies
in pregnancy from diffuse nodular
hyperplasia of prolactin secreting cells
• Usually, at least 1-2 liters of blood loss and
hypovolemic shock
• 1-2% of women suffering significant
postpartum hemorrhage
• inability to lactate after delivery due to
prolactin deficiency occurs and amenorrhea
due to gonadotrophin deficiency classically
develops
Sheehan syndrome
• after delivery, shaved pubic hair or axillary
pubic hair fails to regrow, and waxy skin
depigmentation develops
• Signs of hypothyroidism and
hypoadrenalism may develop
• posterior pituitary (neurohypophysis)
involvement with diabetes insipidus may
occur
• clinical presentation of acute pituitary
apoplexy has only been reported case
CT Findings in Pituitary Apoplexy
• Non-contrast CT is hyperdense in acute
stage and may be more specific than MRI
which is often isodense
• Ring sign, if present is diagnostic
• Useful to exclude subarachnoid hemorrhage
acutely
• However, no pathognomonic findings
Time of diagnosis
5 days
3 weeks later
6 months later
MacCagnan P et al, JCEM 80:2190, 1995
MRI Findings in Pituitary Apoplexy
Stage
Days
Intensity: T1
Intensity: T2
Acute
0-7
Isointense
Very hypointense
(similar to blood)
Subacute
7-21
Moderately
hyperintense
(variable)
Moderately
hyperintense
(variable)
Chronic
21 - years
Very
hyperintense
Very
hyperintense
11-18-03 T1 plain
11-18-03 T1 post gad.
4-10-04 T1 plain
4-10-04 T1 plain
Therapy
• Medical – Acute
– Glucocorticoids in doses to cover acute stress at time
dx made or suspected: hydrocortisone, 300mg/d
– Use of larger doses in presence of severe neurologic
deficits, i.e., decreased states of consciousness;
rationale anecdotal
– Fluid and electrolyte replacement as needed
• Medical – Chronic
– Replacement therapy for hypopituitarism, as
appropriate upon testing
Therapy
•
Surgical
–
Considerable controversy in literature
–
In early reports, recommended for all patients
–
Subsequent reports suggested many patients can
be managed medically
–
Two major endpoints to consider:
Recovery of visual acuity, visual fields, and
oculomotor fx.
Preservation / recovery of pituitary function
Visual Outcome and Timing of Surgery
100
Complete recovery
Partial recovery
No improvement
Percent
80
60
40
20
0
<8 days
>8 days
Visual Acuity
<8 days
>8 days
Visual Fields
<8 days
>8 days
Ocular Paresis
Randeva et al, 1999
Hormone Replacement and Timing of Surgery
Percent requiring replacement
100
Glucocorticoids
Thyroxine
Testosterone
Vasopressin/DDAVP
80
60
40
20
0
2.2
Arafah et al, 90
n=8
6.0
Randeva et al, 99
n=35
Mean Days to Surgery
7.7
Bills et al, 93
n=37
Summary
•
Classical pituitary apoplexy is an acute clinical
syndrome that has life-threatening consequences,
requiring immediate medical and frequently
surgical therapy.
•
Although hemorrhage into a pituitary
macroadenoma is the typical setting, it may be
the first manifestation of the tumor.
•
In more than half of the cases clinical
manifestations are milder or nonexistent.
Summary (2)
•
Immediate institution of glucocorticoid
therapy is essential when the diagnosis is
suspected because of the high frequency of
adrenal insufficiency.
•
Controversy exists concerning the need for
surgical therapy in all cases. However, in
patients with oculoparesis and visual field
impairment, early surgical intervention results
in better functional recovery.
Summary (3)
• Early surgical intervention also appears
to improve the retention and/or recovery
of pituitary function.
• Re-bleeding commonly occurs
irrespective of previous therapy and
careful follow-up is important.