STRATEGIES FOR BETTER SURGERY
| SURGERY FOR BENIGN THYROID DISEASE —Lisa A. Orloff, MD, Professor, Department of Otolaryngology/Head
and Neck Surgery, University of California, San Francisco, School of Medicine
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| Epidemiology: palpable nodules occur in up to 10% of population; >50% of population has nodules on ultrasonography;
majority of people die with nodules (autopsy data), but not necessarily nodules of clinical significance; surgery
indicated for malignancy, compressive symptoms (airway and digestive tract compression), certain endocrine symptoms,
and for diagnosis
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| Benign thyroid nodules: multinodular goiters (consider each nodule individually; typically, colloid adenomas); follicular
adenomas (solitary); adenomatoid nodules (not well encapsulated); Hashimoto’s thyroiditis (potentially associated
with nodularity); benign cysts; diffuse enlargements of thyroid gland; fine needle aspiration (FNA) biopsy—potentially
highly accurate; false-positive rate low; false negative rate exists; up to 28% of FNA biopsies nondiagnostic (repetition of
biopsy required); with 2 nondiagnostic FNA biopsies, consider surgery; molecular investigation—various markers of
tumorgenesis; gene analysis performed on tissue samples; markers and mutations currently investigational and not available
in majority of clinical settings include RET proto-oncogene mutations, tyrosine kinase rearrangements, BRAF mutation
for papillary thyroid carcinoma, ras mutations, epidermal growth factor (EGF) receptor overexpression;
combination of FNA and ultrasonography—further characterizes nodules; leans interpretation to benign rather than
malignant disease; examination of neck beyond thyroid helps in characterization; ultrasonography—useful for follow-
up of nodules when surgery not performed and for screening of families with history of thyroid cancer (CA)
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| Indications for surgery for benign masses: suspect malignancy, even when FNA gives benign diagnosis (sampling
error); obstructive symptoms; recent growth of nodule; follicular lesion on FNA; Graves’ disease and thyrotoxicosis;
cold nodules in patient with history of irradiation; calcification on imaging; elevated serum calcitonin; surgery for nontoxic
goiter—expect goiter to grow or descend over time, and consider surgery while patient healthy or less symptomatic;
if patient with hypothyroidism already receiving thyroid supplementation, no argument for leaving thyroid; history
of airway obstructive symptoms poor indicator of actual obstruction; pulmonary function testing helpful in determining
actual degree of tracheal compression; have low threshold for cross-sectional imaging for substernal or mediastinal goiter
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| Toxic nodules: excision (typically lobectomy) indicated for autonomous hyperfunctioning nodules causing hyperthyroidism
or thyrotoxicosis; risks minimal; residual thyroid function should return to normal; examine tissue for malignancy
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| Graves’ disease: trend in United States to nonsurgical therapy; medical therapy takes minimum of 6 to 12 mo to cause
remission, and relapse rate high in studies (up to 43% in first year), so long-term follow-up necessary; patients with
higher rate of relapse include those with large goiters, higher triiodothyronine (T3) levels at time of diagnosis, those who
smoke, and those with high thyroid-stimulating immunoglobulin (TSI); radioactive iodine (131 I) therapy—takes longest
to achieve euthyroidism, may require repeat doses of 131 I, and carries risk for acute exacerbation of ophthalmopathy;
surgery—rapid, permanent, safe, and successful treatment of hyperthyroidism; tissue available for pathologic evaluation;
best chance of rapidly controlling progression of ophthalmopathy; consider in pregnant patients, those with large
goiters, noncompliant patients, and those who smoke
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| Amount of surgery for benign disease: goiter—total unilateral lobectomy (include isthmus) or total thyroidectomy;
tailor surgery to individual; complications—low risk for complications to parathyroid glands and superior laryngeal
nerve because of modern approaches to identification of these structures
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| Surgical options for Graves’ disease: subtotal thyroidectomy (bilateral subtotal lobectomy); total lobectomy on one
side and subtotal lobectomy on other side; total thyroidectomy; poor correlation between size and endocrine function of
remnant (>50% of patients with remnant develop recurrent hyperthyroidism)
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| Preoperative preparation: vocal fold dysfunction may be asymptomatic, and impairment may indicate underlying malignancy;
determine status of nerve function; thyroid function testing (thyroid-stimulating hormone [TSH] levels) and
calcium levels important (for possible coexistent hyperparathyroidism and management of potential postoperative hypocalcemia);
no conclusive data on value of routine calcitonin testing; Chvostek’s sign testing on every patient to provide
baseline for postoperative difference; arrange for possible assistance from vascular or thoracic surgeons if
substernal or mediastinal extension of disease anticipated
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 | Patient with thyrotoxicosis: screen for atrial fibrillation (AF; found in ≤15% of patients with thyrotoxicosis or cardiac arrhythmia;
resolves when patient becomes euthyroid); medical therapy—consider using (eg, methimazole, propylthiouracil,
carbimazole [not approved in United States]) for 4 to 6 wk to bring patient to euthyroid state before surgery; β-
blockers—consider for symptomatic relief and to minimize cardiac stress and fluctuations in heart rate and blood
pressure; continue until 1 wk after surgery; iodine—can saturate gland, decrease release of hormone, and decrease
vascularity of gland; other options—include lithium, radiologic iodinated contrast agents, plasmapheresis, and peritoneal
dialysis for thyroid storm
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| Avoiding complications: eg, vocal fold paralysis, injury to recurrent laryngeal nerve (RLN); attempt to identify RLN;
watch for external branch of superior laryngeal nerve; identify and preserve parathyroids with blood supply; autotransplant
devascularized parathyroids; if problems known with first side of dissection, consider less extensive procedure for
other side; RLN—anatomy variable; nerve frequently branches outside larynx; if considering nerve monitoring (eg, direct
stimulation, palpation of twitch), have anesthesiologist avoid neuromuscular relaxation; parathyroids—identify inferior
thyroid artery and trace to glands; postoperative hypocalcemia may follow manipulation of glands; routine in many
centers to empirically prescribe calcium supplementation; alternatively, monitor serum calcium while observing for
symptoms, then replace calcium orally and intravenously; consider diuretics (eg, hydrochlorothiazide) to retain calcium;
monitor and replace magnesium as needed to retain proper balance
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| Long-term management: transplanted devascularized parathyroid glands have high rate (80%-90%) of regaining
function (monitor for months); strategies for detecting patients more likely to become hypocalcemic
postoperatively—evidence that patients whose parathyroid hormone dropped to <15 pg/mL in recovery room had
higher likelihood of developing hypocalcemia; study from Korea looked at cutoff value of 15 pg/mL and preoperative
parathyroid hormone (PH) levels and concluded that patients with >70% decline in PH from preoperative to immediate
postoperative period had high incidence of hypocalcemia; <70% decline reliably identified patients who would remain
normocalcemic
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| Preoperative considerations: general vs local anesthesia (most prefer general for thyroidectomy, but local anesthesia
used for parathyroidectomy and minimally invasive thyroidectomy); neuromuscular paralysis and influence on nerve
monitoring; patient positioning, taking care not to overextend neck (recognition of cervical spine disease important); incision
planning helpful in upright awake patient (plan in preop area and modify accordingly)
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| Adjuvant therapy: thyroid hormone replacement and calcium supplementation (monitor for need); management of
ophthalmopathy; management of vocal fold dysfunction when it occurs; monitor remaining thyroid if any
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| Follow-up: thyroid function tests; calcium levels; postoperative laryngoscopy; ultrasonography of residual thyroid
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| Evidence-based guidelines (American Thyroid Association): fair evidence for ultrasonography in all patients
with ≥1 suspected nodules; inconclusive evidence for routine calcitonin testing; evidence against routine preoperative
thyroglobulin testing; evidence for close observation or surgical intervention for nodules that have had >1 nondiagnostic
FNA biopsy; adjuncts to imaging and FNA biopsy include radioiodine scan for indeterminate cytology (patients with hot
nodules have >98% chance of nodule being benign; cold nodules in this setting warrant surgery)
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| ORBITAL DECOMPRESSION FOR GRAVES’ DISEASE —Andrew N. Goldberg, MD, Professor and Director, Division
of Rhinology and Sinus Surgery, Department of Otolaryngology/Head and Neck Surgery, University of California, San
Francisco, School of Medicine
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| Multidisciplinary approach: essential; endocrinologist manages preoperatively; ophthalmologist determines level of
neuropathy and measures visual field deficits if present; endocrine surgeon helpful in managing thyroid; otolaryngologist
needed for decompression
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| Indications for surgery: optic neuropathy; increased intraocular pressure (IOP); proptosis, especially with keratitis;
retro-orbital ache
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| Before surgery: determine whether eye disease in active phase (not optimal to operate); stop tobacco use; document visual
status; active disease—injection and edema of conjunctiva and lids; skin and caruncle show evidence of active disease;
first treat medically with steroids, radiation therapy, or other methods; smoking—higher prevalence of TED in
smokers; disease more severe and longer in duration; visual status—visual field examination; visual acuity; color vision
(one of first areas of deficit); obtain photo documentation; laboratory tests—TSH; TSI (high TSI sign of active disease)
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| Decompression: orbit contains fat with lymphocytic infiltration; eye muscles also enlarged; procedure geared toward
enlarging orbit to accommodate increased volume of contents; at present, decompressions involve medial wall and part of
floor of orbit; balanced decompression
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| Procedures: endoscopic decompression—speaker performs medial and inferior endoscopic decompression, involving
medial wall of orbit and medial part of floor (inferior orbit), medial to infraorbital nerve; decompression 3 to 5 mm; lateral
decompression adds few more millimeters; balanced decompression—take down small part of floor of orbit as
well; speaker conservative with this because patients get esotropic with removal of too much of this area, particularly if
not balanced with lateral decompression
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| Technique: maxillary antrostomy; ethmoidectomy; mucosa removed from lamina papyracea; microdebrider used to remove
mucosa from floor of orbit (before periorbita exposed); puncture bone (in thinnest part of orbit), but stay out of periorbita
(leave intact); speaker leaves posterior strut between medial and inferior walls to support cone of orbit; careful
not to remove too much bone superiorly, so frontal sinus does not get closed off; periorbita incised from posterior to anterior
and orbital fat prolapses; remove slips of periorbita that create sling, and apply gentle pressure on globe to allow
more prolapse of fat; take care not to damage medial rectus muscle (found below periorbita and posteriorly); no packing
needed; lateral decompression after endoscopic decompression
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| Balanced decompression: balanced technique popular since 1990s; controversies—whether to do each eye at separate
times, medial on both at one time, and then lateral on both at another time; balanced decompression provides symmetric
repositioning of globe and eye muscles; diplopia—less common (≈20%) with modern surgical techniques;
removal of medial floor potentially unnecessary; removal of entire floor predisposes to diplopia; orbital sling technique
possibility
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| Adjuncts: dexamethasone (Decadron); antibiotics; oxidized cellulose (Surgicel; used in lateral part of decompression);
depo- steroid; lone stars (retractors); image guidance system used for endoscopic portion of decompression
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| Tips: informed consent—tell patient about possibility of diplopia, potential need for another surgery, potential need for
eyelid surgery for coverage of cornea; muscle hypertrophy—decompression more difficult (muscle more difficult to decompress
than fat; important to keep in mind when discussing consequences with patients; less decompression with stiff
globe preoperatively; postoperative concerns—optic nerve; improved visual acuity; return of color vision; presence of
double vision; eyelids
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| SPARING THE EYE WHEN TREATING SINONASAL MALIGNANCIES —Paul A. Levine, MD, Robert W. Cantrell
Professor and Chairman, Director, Department of Head and Neck Surgical Oncology, University of Virginia Health System,
Charlottesville
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| Orbital exenteration: once believed that after preoperative radiation therapy, orbital exenteration necessary even if no
tumor present at time of surgery; in 1974, physician noted that in patients with maxillary sinus cancers, orbital exenteration
did not significantly help cure rate
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| Eye-sparing protocol: 1996 study—follow-up of initial paper from 1988; looked at 74 patients with preoperative radiation
therapy ± chemotherapy (depending on tumor type and stage of disease); 41 patients had either bony erosion or direct
periorbital invasion; operation consisted of dissecting globe away from eroded area, frozen section analysis, and
resection of involved periorbita to negative margins (replaced with fascia or split thickness skin graft if necessary); results
of first series in 1988—5 patients had orbital exenterations; of remaining 36 patients, 4 had recurrent disease in orbit,
none at primary site; half of patients had no orbital complications; 1998 article—showed presence of periorbital
fascia holding periauricular fat in place, deep and separate from periorbita; this permits periorbital resection with eye
preservation; not seen on imaging because of thinness, and difficult to see during surgery; dissection of periorbita (resistant
to tumor invasion) possible, with maintenance of integrity of eye; cannot save eye in everyone
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Educational Objectives
| The goal of this program is to provide the listener with information on surgery for benign thyroid nodules, orbital decompression
for Graves’ disease, and eye-sparing techniques for treating sinonasal malignancies. After hearing and assimilating
this program, the clinician will be better able to:
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| 1. Discuss indications for surgery for benign thyroid nodules.
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| 2. Explain how to avoid complications of surgery for benign thyroid nodules.
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| 3. Describe the technique for endoscopic orbital decompression for thyroid eye disease.
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| 4. Define balanced orbital decompression surgery.
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| 5. Describe eye-sparing techniques for treating sinonasal malignancies.
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Suggested Reading
Baldeschi L, et al: Early versus late orbital decompression in Graves’ orbitopathy: a retrospective study in 125 patients.
Ophthalmology 113:874, 2006; Batra PS, Lanza DC: Endoscopic power-assisted orbital exenteration. Am J Rhinol
19:297, 2005; Cansiz H, et al: Three-wall orbital decompression superiority to 2-wall orbital decompression in thyroid-
associated ophthalmopathy. J Oral Maxillofac Surg 64:763, 2006; Cappelli C, et al: The predictive value of ultrasound
findings in the management of thyroid nodules. QJM 100:29, 2007; Chandrasekaran S, et al: Refractive change in
thyroid disease (a neglected clinical sign). Br J Ophthalmol 90:307, 2006; Erodogan, et al: Natureal course of benign
thyroid nodules in moderately iodine-deficient area. Clin Endocrinol (Oxf) 65:767, 2006; Filetti, et al: Nonsurgical approaches
to the management f thyroid nodules. Nat Clin Pract Endocrinol Metab 2:384, 2006; Liao SL, et al: Transforniceal
lateral deep bone decompression—a modified technique to prevent postoperative diplopia in patients with disfiguring
exophthalmos due to dysthyroid orbitopathy. J Formos Med Assoc 105:611, 2006; Metson R, Pletcher SD: Endoscopic
orbital and optic nerve decompression. Otolaryngol Clin North Am 39:551, 2006; Perry JD: Transcaruncular orbital
decompression: an alternate procedure Graves ophthalmopathy with compressive optic neuropathy. Am J Ophthalmol
142:889, 2006; Pletcher SD, et al: Endoscopic orbital and optic nerve decompression. Otolaryngol Clin North Am
39:943, 2006; Robert PY, et al: Decrease o intraocular pressure after fat-removal orbital decompression in Graves disease.
Ophthal Plast Reconstr Surg 22:92, 2006; Rosen JE, Stone MD: Contemporary diagnostic approach to the thyroid
nodule. J Surg Oncol 94:649, 2006; Sakorafas GH, et al: Thyroid nodules: does the suspicion for malignancy
really justify the increased thyroidectomy rates? Surg Oncol 15:43, 2006; Wang N, et al: Association of sonographically
detected calcification with thyroid carcinoma. Head Neck 28:1077, 2006.
Faculty Disclosure
In adherence to ACCME guidelines, the Audio-Digest Foundation requests all lecturers to disclose any significant financial
relationship with the manufacturer or provider of any commercial product or service discussed. For this issue the faculty reports
nothing to disclose.
Drs. Orloff and Goldberg were recorded at Head and Neck Endocrine Surgery, held October 27-28, 2006, in San
Francisco, CA, and sponsored by the University of California, San Francisco, School of Medicine. Dr. Levine was recorded
at the 26th Annual James A. Harrill Lecture, held April 21-22, 2006, in Winston-Salem, NC, and sponsored
by Wake Forest University School of Medicine, in partnership with Northwest Area Health Education Center. The
Audio-Digest Foundation thanks the speakers and the sponsors for their cooperation in the production of this program.
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