Minimally Invasive RadioGuided Parathyroidectomy

1

• Minimally Invasive Radio-Guided Parathyroidectomy

(MIRP)
E.A. Wieman
2
(No Transcript)
3
Anatomy

• Location of superior gland
• 4th branchial arch
• Undersurface of the thyroid lobe
• Superior to the inferior thyroid artery (ITA)
  and lateral to plane of recurrent laryngeal nerve
  (RLN).
• Related to
• cricothyroid muscle
• pharyngeal constrictors
• superior laryngeal nerve
• Location of inferior gland
• 3rd branchial arch
• Migrate with Thymus-5/52
• Caudal to the (ITA),
• Medial and anterior to the (RLN).

4
Ectopic Locations

• Superior parathyroid
• Can be located inferior to inferior glands
• Between aortopulmonary window and base of skull
• Inferior parathyroid
• As low as the aortic notch
• 2X likely to have an adenoma than superior
• Common ectopic site is thymus

5
(No Transcript)
6
Patient Hx

• P/C
• 48 YO white female presents for suspected
  hyperparathyroid on GP referral after blood test
  reveals
• Elevated Ca levels
• Normal Ca levels (2.1-2.62 mmol/L)
• Elevated (gt3.0mmol/L) require treatment of
  underlying cause

7
Initial Management

• Initial Invx
• Indication for procedure
• Contraindications for Surgery
• Patient Outcome Discussion
• Desired outcome
• Probability of achieving desired outcome
• Potential Complications
• Short Term Injury
• Long term Injury
• Questions from patient
• Pre-op Instructions
• Rx/lifestyle/nutritional needs or changes
• Psychological management
• Financial issues
• Legal issues

8
Hx P/C

• Presented to GP
• Constipation 6/12
• Evacuates rectum daily, digitally
• Intermittent diarrhoea 6/12 with intermittent
  bright red tensemus
• Abdominal Pain (Groans )
• Gradual, generalized, non radiating, intermittent
  abdominal pain 6/12
• Pain rated 5/10
• No aggravating/relieving factors
• Nil (Stones, Bones, Psychic Moans)
• N/V
• Renal stones
• Bone pain
• Thirst
• CNS ?s
• MSS ?s

9
Current Rx

• PO
• Venlafaxine (Efexor) OD
• Raises BP
• Thyroxine OD
• Raises BP
• Alter blood glucose levels
• Flurazepam (Dalmane) nocte
• Longest acting of all benzos T ½ -40-250 hours
• Bromazepam (Lexotan) b.d.
• T ½ 10-20 hours
• P450 metabolism
• Gliclazide mane
• Sulfa allergy
• Disulfuram reaction
• Rosiglitazone (Avandia) mane
• Check LFTs every 2-3 months
• Fluid retention

• IM
• B12 Injxn1/52
• NKDA

10
PMHx-via Rx

• Constipation
• Hypothyroidism
• Hemithyroidectomy 10 yrs previous
• DM II
• Bipolar Affective Disorder
• ERCP 3 yrs ago
• Appendectomy 8 yrs previous
• Hysterectomy 10 yrs previous

• Bisacodyl
• Thyroxine
• Gliclazide
• Rosiglitazone
• Venlafaxine
• Flurazepam
• Bromazepam
• B12

11

• SoHx

ROS

• Nil
• Kids
• ETOH
• Cigs
• Retired Shopkeeper
• Lives at home in with her husband

• GIT-per P/C
• RS-Nil
• CVS
• Orthopnoea but nil PND
• CNS
• fell out of bed 2/52, otherwise fine
• MSS-Nil

12

• Examination-Relevant Findings

• General Appearance
• Increased BMI (35-40)
• Unkempt
• Neck
• No palp nodules
• No L/A
• CVS
• Bipedal oedema
• RS
• Bilateral creps at lung bases

• GIT
• Fatty apron
• 2 scars
• Right oblique
• Pfannistiel
• CNS
• Tardive dyskinesia
• Resting tremor
• MSS-Nil

13
Initial Investigations
?

• PTH ( )
• Serum Calcium ( )
• Serum Calcium is the standard calcium that is
  most easily measured.
• Most hyper-PTH patients has overtly elevated
  PTH/Ca
• Ionized Calcium
• Ionized calcium is the calcium in blood that is
  floating free of proteins
• Expensive
• Variable due to pH
• Used in borderline elevation of PTH and calcium

?
14
Differential-Hypercalcemia
Urea v. Urea Norm

• ?
• Albumin raised Albumin normal/low
• ?

?
Phosphate /norm v. Phosphate /norm
?
Urea Norm ? Primary/Tertiary
Hyperparathyroidism

? Cuffed Specimen
?
?
?
?
? Dehydration
?Alk Phos v. ? Alk Phos
Myeloma (? plasma protein)Vita D ExcessMilk
Alkali Syndrome
Bone metsSarcoidosisThyrotoxicosis
15
Primary/Secondary/Tertiary Hyperparathyroidism

• Primary ? PTH, normal or ? Ca 2
• Adenoma 90
• Hyperplasia 10
• Carcinoma lt 0.1
• Secondary ? PTH appropriate to low Ca 2
• Chronic Renal Failure
• Vitamin D Deficiency
• Pseudohypoparathyroidism
• Tertiary
• Continued excess PTH secretion following
  prolonged secondary hyperparathyroidism. (M
  C)

16
Points to Remember

• 95 of people with hyperparathyroidism will have
  high calcium and high PTH levels
• 4 of parathyroid patients have high calcium but
  normal PTH
• Would normally expect low PTH with ? calcium
• 3 suppressed glands/ 1 overactive gland
  maintaining PTH level
• only about 25 of endocrinologists will make the
  correct diagnosis
• 1 of parathyroid patients will have normal
  calcium levels and high PTH levels.
• Difficult Dx- 2 common features
• high ionized calcium levels
• kidney stones. 

17
Hereditary Factors

• MEN1 - Multiple endocrine neoplasia type 1
  (previously Wermer syndrome) tumors of
  parathyroid, pituitary, and pancreas
• MEN2A - Multiple endocrine neoplasia type 2A
  (previously Sipple syndrome) medullary carcinoma
  of the thyroid, adrenal pheochromocytoma, and
  parathyroid tumors
• HPT-JT - Hyperparathyroidism, jaw tumor syndrome
• FIHPT - Familial isolated hyperparathyroidism
• ADMH - Autosomal dominant mild hyperparathyroidism
  or familial hypercalcemia with hypercalcuria
• FHH - Familial hypocalciuric hypercalcemia
• NSHPT - Neonatal severe hyperparathyroidism

18
Investigation Plan

• PTH
• Calcium
• UE
• FBC
• (Urine)
• CXR
• ECG
• Technetium (Tc 99) MIBI Scan

19
Sestamibi Tc-99 (Cardiolite)

• Introduced in 1984 for cardiac stress tests
• Described in 1989 - Coakley et al, Nucl Med
  Commun 1989
• 99Tcm Sestamibi--A New Agent for Parathyroid
  Imaging.
• Radionucleotide concentrated in areas of
  increased metabolism
• Molecule passes cells membranes passively the
  driving force is the negative membrane potential
• Once intracellular it further accumulates in the
  mitochondria where the membrane potential is even
  lower
• Tissues rich in mitochondria
• Heart
• Salivary glands
• Thyroid
• Parathyroids

20
Sestamibi Tc-99Planar scan

• Injected IV
• Time lapse
• XR
• Metabolized by liver

21
Diagnostic Clues

• DDX-Man?-Horrible woman?

Hans Schaefer
Riley Senft
All Man
?
?
?
?
?
22
?
?
?
?
23
Sestamibi Scan

• Advantages
• Fast
• Safe
• Reliable
• IDs 90 solitary adenomas (sensitivity)
• 98 of these are the offending gland
  (specificity)
• Reveals eptopic glands

• Disadvantages
• Misses some 2o adenomas (17)
• Misses hyperplastic glands
• Provides little value in cases of 4 gland
  hyperplasia

24
SPECT Scan

• Single photon emissions CT
• Fusion of SestamibiCT scan
• 2D/3D imaging
• Highly valuable in locating ectopic parathyroids
• Krauz, et al. World J Surg. 2006
• Cost effectiveness vs. BNEUS is questionable
• Ruda J, et al Arch Otolarngol Head and Neck
  Surg.2006

25
Indications for Surgery

• Symptomatic hyperparathyroidism
• Bone pain
• Depression
• Gastric symptoms
• Serum calcium levels greater than 11.4 mg/dL
• Creatinine clearance reduced by 30
• A 24-hour urinary calcium excretion of more than
  400 mg
• Bone mass of more than 2 standard deviations less
  than expected ie decreased cortical bone density

26
Surgical Contraindications

• Anatomical anomalies
• Bleeding Disorders
• Immunosuppresion
• Rx issues
• Anesthetic issues (GA)
• Current Rx

27
PARATHYROIDECTOMY INFORMED CONSENTMinimally-Invas
ive Radioguided Parathyroidectomy (MIRP)

• Parathyroidectomy is an operation in which one or
  more parathyroid glands are removed.
• This operation is performed to control
  hyperparathyroidism caused by
• Parathyroid adenoma
• Parathyroid hyperplasia
• In rare instances, surgery is performed on the
  parathyroid glands in order to remove a
  parathyroid cancer.
• Hyperparathyroidism is associated with bone pain,
  abdominal pain, constipation, musculoskeletal,
  and neurological changes
• Any operation has general risks including
  reactions to the anesthetic, chest infections,
  blood clots, heart and circulation problems, and
  wound infection.

28
Specific Risks Associated with Parathyroid Surgery

• Post-Op Bleed
• Pre-tracheal hematoma-airway obstruction
• Sub-platysmal hematoma-Aspiration
• Hoarseness of the Voice
• Permanent in up to 1-2 of cases
• Recurrent laryngeal damage
• Superior laryngeal damage (voice weakness)
• Post-Op Hypocalcemia-(6-12/12)
• Hungry Bone syndrome -aches/pain, seizure,
  arrhythmia, prolonged Q-T, numbness tetany,
  paraesthesias, Chvosteks sign, Trousseaus sign
• Pre-op Vita D
• Post-Op Vita D, Oral Calcium

29
Specific Risks Associated with Parathyroid Surgery

• Scarring
• Keloid formation- Silicone gel tapes, steroids
• Persistent hyperparathyroidism
• 5 of parathyroid tumors cannot be found at
  operation and the blood calcium will remain
  elevated
• Recurrent hyperparathyroidism
• Remaining glands overeact causing hypocalcemia

30
Management Prior to Surgery, When Surgery is
Indicated

• Initial Invx- HP,PTH, Calcium, UE, FBC,
  Technetium (Tc 99) MIBI Scan, CXR, ECG
• Indication for procedure-Symptomatic
  hyperparathyroidism, Single Adenoma
• Contraindications for Surgery-Nil
• Patient Outcome Discussion
• Desired outcome- Decrease blood
  PTH/Ca2,Constipation, Abdominal Pain relief
• Probability of achieving desired outcome- High
  (success rate gt95)
• Potential Complications
• Short Term Injury- Bleed, Hungry Bone
  Syndrome/Hypocalcaemia
• Long term Injury- Hoarseness, Scar, Recurrent
  HyperCa, Persistent HyperCa
• Questions from patient
• Pre-op Instructions
• Rx/lifestyle/nutritional needs or
  changes-Constipation/Pain Management, Manage DM
• Psychological management-via Rx
• Financial issues-medical card
• Legal issues-next of kin etc

31
Pre-Op Plan

• Surgery Indicated (symptomatic/INVX)
• Admit Consent
• Vitals
• H/P
• Changes in symptoms
• Changes in Rx
• Lab review
• PTH
• Ca2
• UE
• FBC
• ECG
• Rx
• C/I-nil
• NKDA
• Anesthetic-GA, no allergy

32
Pre-Op-contd.

• Imaging Review
• Sestamibi
• CXR
• Pre-Op nutrition
• Midnight previous no food
• Water only
• Pre-Op Rx
• Abx-nil
• Vita D
• Pre-Op Tx
• Sestamibi injection (morning of or previous
  evening)
• Pre-Op Theatre Requisites
• Fluid
• Hartmans
• Blood-nil
• Equipment
• Surgical Instrument (preference lists)
• Intra-operative instruments (gamma probe, iPTH)
• Patient Positioning

33
Operative Requirements

• Equipment
• Surgical Instrument (preference lists)
• Intra-operative instruments (gamma probe, iPTH)
• Patient Positioning
• Accessory equipment
• Procedure Overview
• Objectives
• Excisional
• Procedure
• Opening
• Landmarks
• Risky aspects
• Localisation, Identification, Excision, ID2X
• Wound Closure
• Deep
• Superficial
• Drainage
• Dressing

34
What Things Look Like

• Debakey Atraumatic Forceps

• Metzenbaum
• Dissecting
• Scissors

• Fine Non-Toothed
• Dissecting Forceps

• Joll Thyroid Retractor

?
?
?
?

• Lahey Angle/Spencer Wells Forceps

• Rutherford
• Morrison
• Forceps

• Curved Mayo
• Scissors

?
?
?
?
?

• Plain Dressing
• Forceps

• Mixture Right Angle Forceps

• Skin Hook Retractor

?
?

• Rake Retractor

?
?
?

• Rampleys Sponge
• Holding Forceps

• Babcock
• Forceps

• Langenbeck Retractor

35
Intra-operative GuidanceGamma Probe
36
iPTH
(MC)
37
Patient Positioning
?
?
38
Opening
(MC)
39
Opening
(MC)
40
Localisation

• The thyroid lobe
• Elevated-off the common carotid artery
• Retracted-medially.
• The inferior thyroid artery
• Identified-blunt and sharp dissection of the
  areolar tissue anteriorly and medially to the
  common carotid artery and posteromedially to the
  thyroid lobe
• The recurrent laryngeal nerve
• The intersection of the inferior thyroid artery
  and the recurrent laryngeal nerve is an important
  landmark
• The superior parathyroid glands
• Located
• Dorsal to the upper 2/3 of the thyroid lobe
• Posterior to the recurrent laryngeal nerve.
• The inferior glands-Less consistent in location
• Located
• Inferior to the inferior thyroid artery
• Ventral to the recurrent laryngeal nerve.
• Usually within 1 cm of the inferior lobe of the
  thyroid gland.

41
Localisation
42
Localisation
43
Identification-Part 1-Vis/RadioGuided
?
(MC)
44
Excision
45
Identification-Part2-Radioguided

• Adenomatous appearance
• Radiation is 20 of background on removal (ex
  vivo)
• Excised gland is compared to remaining background
  to confirm that all affected glands are excised

46
Algorithm for MIRP
Identification-Part 3-iPTH
PTH / Calcium
Sestemibi scan
Solitary adenoma
Negative or MGD
Unilateral exploration
Bilateral exploration
gt50 iPTH
lt50 iPTH
(MC)
47
Closure

• Deep
• Vicryl 2-0
• Superficial
• Dexon 4-0
• Steri-Strips
• Large plaster
• Both
• Absorbable
• Synthetic
• Multi-filament

48
Post-Operative Requirements

• Discussion with Family Members
• Operation
• Prognosis
• Documentation
• Dictation to Primary care physician
• Chart documentatation
• Wound Management
• Inspect for infection
• Change Dressing
• Stitches removed by GP
• Rx
• Pain-Paracetemol
• Abx-Nil
• Symptoms
• Nutrition
• Discharge

• Follow up
• 6/52
• Symptoms, Scar, PTH, Ca

49
Advantages of MIRP

• Smaller incision
• 25 minutes
• Pain
• Cost
• Local Anaesthesia
• Haematoma
• Recurrent laryngeal nerve injury
• Tissue planes undisturbed
• Contralateral structures preserved
• Less post-op hypocalcaemia

(MC)
50
Questions

• ERCP 3years ago-Indication?
• (Endoscopic Retrograde Cholangiopancreatography)
• HyperCa?
• Obstrxn?
• MEN?
• Hemithyroidectomy 10 years ago
• MEN1 - Multiple endocrine neoplasia type 1
  (previously Wermer syndrome) tumors of
  parathyroid, pituitary, and pancreas
• MEN2A - Multiple endocrine neoplasia type 2A
  (previously Sipple syndrome) medullary carcinoma
  of the thyroid, adrenal pheochromocytoma, and
  parathyroid

51
Referrences

• Krauz, et al. World J Surg. 2006
• Ruda J, et al Arch Otolarngol Head and Neck
  Surg.2006
• Basic Surgical Skills Manual-Iain Skinner
• Hyperparathyroidism, La Bagnara J,emedicine.com
• www.parathyroid.com

52
(No Transcript)