Acromegaly progresses slowly, and the initial symptoms and signs are diverse, nonspecific, and easily neglected. Proper diagnosis may take years. Abnormal changes in facial appearance and extremities are the most common symptoms prompting a patient to seek help.5
Acromegaly diagnosis is established according to clinical signs, laboratory data, and radiographic examination. Serologic examination primarily reveals elevated circulating GH and IGF-1 levels.4
MRI is the best diagnostic imaging tool, and helps to identify the extent of sella turcica enlargement.5
However, two-dimensional morphological changes of the hypophyseal fossa of the sella turcica can also be observed on serial lateral cephalometry; thus, orthodontists may play a role in early detection of acromegaly.
The sella turcica is the intracranial aspect of the sphenoid bone. The saddle-shape fossa is encircled from the top by the anterior and posterior clinoid processes. The anterior wall develops in a straight cranial-caudal direction.5
Nagaraj et al. studied the size of the sella turcica in an Indian population by measuring it on lateral cephalometric radiographs of relatively healthy patients aged 8 to 30 years.6
Their results showed a mean anteroposterior dimension of 11.83 mm (range 8–16 mm) and a mean depth of 8.21 mm (range 5–13 mm). In our patient, the pre-surgical MRI revealed a sella turcica of 16 mm in anteroposterior dimension and 14 mm in depth. With respect to normal growth of the cranial base, the anterior sella turcica stops growing at approximately 7 years of age, while posterior part continues growing until 16 or 17 years of age.7
Therefore, abnormal increase in the dimension or a change in the direction of growth of the anterior wall warrants evaluation for the presence of pituitary gland abnormality.
Our patient developed irregular menses after orthodontic treatment. According to Kaltsas et al. (1999), menstrual irregularity is common in 50–75% of female patients with acromegaly.8
On the basis of this clinical symptom, along with exaggerated growth of facial soft tissue and extremities, abnormal enlargement and changes of sella turcica morphology, gradually protruding lower jaw, and thorough serology examinations, the patient was diagnosed with acromegaly.
The goal of acromegaly management is to remove the origin of abnormal GH secretion or suppress its secretion, thus alleviating the clinical symptoms and maintaining the pituitary gland function;4
this is accomplished with surgery, irradiation, and pharmacotherapy. Recent information indicates that GH should be 2.5 ng/ml or less after surgery, and the circulating IGF-1 level should be within the normal range.9,10
The vast majority of these tumors are a localized mass seated in the sella turcica; therefore, surgical debulking and decompressing under endoscopy remains the gold standard. For patients in whom surgery is contraindicated or failed, radiotherapy including X-irradiation or proton beam therapy is indicated. Drug therapy is another adjunctive treatment when either surgery or radiotherapy is unsuccessful, or when surgery is contraindicated. In those cases, dopaminergic analogs (bromocriptine) and somatostatin analogs (octreotide) are the two most commonly used agents to inhibit the secretion of GH.11
Mandibular body length was dramatically shortened in the present patient after the bilateral sagittal split osteotomy (Figure 12)
. However, due to excessive secretion of GH caused by the PA, the mandibular length increased by 1.64 mm over the next four years. After the trans-sphenoidal adenomectomy, the rate of increase of mandibular length and ramus height dropped significantly from +0.33 to 0 mm/ and +3.57 to +0.32 mm/year, respectively (Table 1)
The upper anterior facial height increased 1 mm as a result of the orthognathic surgery (Figure 12)
. However, the upper anterior facial height increased a further 3.03 mm within 5 years (0.61 mm/year) as the acromegaly progressed. After the brain surgery, there was only a slight increase in anterior facial height at a rate of 0.17 mm/year. The same phenomenon was observed in the lower anterior facial height (Table 1, Figure 12)
Herrmann et al. observed that acromegalyassociated craniofacial morphological changes in the maxilla are different from those in the mandible.12 Their study demonstrated that the midface bony structure will increase in vertical dimension instead of anterior-posterior dimension. This finding is consistent with the increase in upper anterior facial height as the disease progressed in our patient. However, Herrmann et al. further indicated that apart from the mandible height, the mandibular length is the most affected by the disease, which is in contrast to the findings in our patient. In our case, the morphological change in mandibular length was less than that in the vertical direction (Table 1)
Cosmetic changes associated with acromegaly are usually of great concern to the patients. However, after the disease is cleared medically, plastic surgery and orthognathic surgery may be performed. In our case, if the disease is under control, a second orthodontic combined orthognathic surgery treatment could be considered. However, at present, our patient does not intend to undergo another orthognathic treatment or plastic surgery.
The linear change of mandible length, ramus height and anterior facial height after debonding, brain surgery (5 years after orthodontic treatment) and 7 years after the brain surgery. # Upper Anterior Facial Height (UAFH) ## Lower anterior facial height (LAFH) *Rate of increase from debonding to post-treatment 5-year follow-up **Rate of increase from post-treatment 5 year to 12-year follow-up View Hi-Res Image
The change of mandible body length (Gn-Go), mandible ramus height (Co-Go), upper anterior facial height (UAFH, N-ANS), and lower anterior facial height (LAFH, ANS-Me) from pretreatment to post treatment 12-year follow-up (timeline shown in years). View Hi-Res Image