1 Background
Carotid artery aneurysms are rare (Painter et al., 1985), and there are very few case reports. Internal carotid artery aneurysms (ICAAs) are usually clinically asymptomatic, but giant ICAAs sometimes manifest as progressive dysphagia (Kubis et al., 2000; Vasileiadis et al., 2010), a pulsating mass (Kubis et al., 2000), airway obstruction (Kubis et al., 2000), odynophagia, or tonsil asymmetry (Altin et al., 2012). Dysphagia resulting from a giant ICAA may cause compression of the posterior pharyngeal wall (Waespe et al., 1988; Sergi et al., 2006), vagus nerve (cranial nerve [CN] X) (Waespe et al., 1988), glossopharyngeal nerve (CN IX) (Decrinis et al., 1996; Waespe et al., 1988), or hypoglossal nerve (CN XII) (Waespe et al., 1988; Lieschke et al., 1988).

In the present study, we report the clinical outcome of swallowing training (ST) combined with neuromuscular electric stimulation (NMES) of the swallowing muscles in the management of a patient with postoperative persistent dysphagia resulting from a left ICAA.

2 Results
The patient regained swallowing function after a total of 17 treatment sessions. She was able to maintain a soft-food diet and drink water. Swallowing ability improved, as assessed by bedside swallowing evaluation (BSE), and she passed the 100-mL water test (Table 1). The nasogastric tube was removed successfully. She ultimately achieved level 5 on the functional oral intake scale (FOIS). The patient showed no signs of respiratory complication on regular follow-ups, and she was able to continue her previous daily activities.

Table 1 Clinical assessment of swallowing ability using a thick liquid and puree

3 Discussion
Giant ICAAs are clinically rare, and have hardly been noted in the past 10 years (Painter et al., 1985; Vasileiadis et al., 2010). Complications of giant ICAAs include thromboembolic or neurologic complications (Painter et al., 1985), airway compression with dyspnea (Altin et al., 2012), compression of CNs IX–XII resulting in hoarseness (Waespe et al., 1988; Altin et al., 2012), and/or dysphagia (Kubis et al., 2000; Sergi et al., 2006; Vasileiadis et al., 2010; Altin et al., 2012).

Previous studies have described the spontaneous relief of neurologic complications within a few days to 1 month after surgical intervention (de Donato et al., 2006; Biasi et al., 2008; Hanabusa et al., 2010). To date, no study has provided recommendations for therapeutic strategies effective in the management of persistent dysphagia resulting from a giant ICAA after surgical intervention. Our case provided a few clues as to how the disease had manifested. Although there was no definite major CN injury sustained during surgery, the case was complicated by weakness of the left vocal cord, resulting in hoarseness. This symptom may have been caused by postoperative inflammation, which is quickly relieved, according to previous studies (Waespe et al., 1988; de Donato et al., 2006). The severe persistent oropharyngeal dysphagia noted in our patient may have been related to prolonged left CN IX compression, discovered during the surgical procedure. The finding of tongue deviation is also suggestive of CN XII involvement. CN IX, part of CN X, CN XI, and CN XII, as well as the jugular vein and carotid artery, meet in the retrostyloid space (Waespe et al., 1988). We assumed that the growing aneurysm may have compressed, stretched, or induced ischemia in the nerves in this area, resulting in dysfunction.

Our patient did not initially respond to ST; thus, NMES and ST combination therapy was employed. Burnett et al. (2003) reported that NMES may lower the hyolaryngeal complex and provide resistance to hyolaryngeal elevation; as such, it can be used for muscle strengthening. Oh et al. (2007) demonstrated in a prospective case study that NMES has positive effects on cortical activation, cortical excitability, and neural activation. In our case, electrodes were applied on the right side of the neck, lateral to the midline, to increase strength and awareness in her right (sound) side. This was combined with posture regulation, involving turning her head toward the left (affected) side to close the weak pharynx and prevent choking, as well as training to modify posture during swallowing.

Evaluation of the patient’s swallowing ability was performed using BSE, FOIS, and the 100-mL water test. We elected to not perform videofluoroscopic swallowing assessment before treatment due to the old age of the patient and because her severe dysphagia caused her to choke when she consumed food of any consistency. While recovery of our patient after combination NMES and ST was remarkable, this case raises a few questions that can only be resolved with further study. For example, we performed NMES and ST twice every week, and whether more intensive treatment would have reduced the treatment course is unknown and worth investigating. Further, it is important to note that the decision to apply combination therapy was made 6 weeks after surgical intervention, when the patient showed no signs of recovering from dysphagia. It is possible, however, that resolution of the nerve palsies would have spontaneously occurred later. As such, the specific contribution of the therapeutic strategy employed remains to be determined.

In conclusion, the findings of this case demonstrate the efficacy of combination NMES and ST in the treatment of dysphagia that developed in a patient diagnosed with a giant left ICAA. As such, this therapeutic approach may have a positive clinical rehabilitative effect, but further studies will be required to assess its long-term effects.

4 Materials and Methods
A 99-year-old woman was referred to our rehabilitation department for dysphagia evaluation and therapy. She had managed hypertension for many years with regular medication. She had been diagnosed with cervical cancer 4 years before admission, and also had a left femoral neck fracture due to an accidental fall 1 year before admission. Besides this, she denied a history of other systemic disorders, head and neck trauma, or stroke.

The patient first visited our otolaryngologic outpatient clinic for assistance with a mass on the left side of her neck that had been gradually growing for approximately 1 year. She also had developed progressive dysphagia over several months to the point that she could only swallow a small amount of water. Initial nasopharyn- goscopic examination revealed posterior pulsatile masses on both sides of the oropharynx. The nasal cavity, nasopharynx, oral cavity, hypopharynx, and larynx were otherwise unremarkable. Head and neck computed tomography was performed under the impression of the aberrant carotid artery, which revealed a giant left proximal ICAA (4.7 × 3.4 cm) near the carotid bifurcation (Figure 1). She was transferred to the cardiovascular surgery department for surgical assessment.

Figure 1 Computed tomographic images of the head and neck, showing a giant left proximal internal carotid artery aneurysm (4.7 × 3.4 cm) near the carotid bifurcation

On admission, the patient had no signs of fever, chest tightness, nausea, vomiting, abdominal pain, dysuria, heartburn, muscle weakness, or neck bruits. Head and neck magnetic resonance imaging and magnetic resonance angiography confirmed a 4.5 × 3.5 × 3.5-cm giant ICAA in the left parapharyngeal space (Figure 2). Findings also demonstrated an unsaturated flow signal in the left internal carotid artery (ICA) distal to the aneurysm on the neck, an infundibular dilatation in the right posterior communicating artery with a very small aneurysm, and changes in the brain due to small vessel disease with age. Based on the patient’s clinical history and imaging findings, left extracranial ICAA was diagnosed.

Figure 2 Magnetic resonance angiographic images, revealing a giant internal carotid artery aneurysm (4.5 × 3.5 × 3.5 cm) in the left parapharyngeal space

The patient underwent surgery 2 days after admission. Endarterectomy of the left common carotid artery (CCA) and external carotid artery (ECA) and aneurysmectomy of the ICA were performed. Since the glossopharyngeal nerve was adhered to the wall of the aneurysm, the aneurysm surrounding the nerve was cut and reconstructed with a Gore-Tex graft. Left CCA-to-ICA/ECA bypass grafting also was performed successfully. The patient’s dysphagia failed to alleviate, and she developed aspiration pneumonia on the third day after surgery. A nasogastric tube was inserted for nutrition supply, and follow-up nasopharyngoscopic examination, performed 10 days after surgery, revealed salivary stasis in both pyriform sinuses, especially on the left side, but no focal lesion (Figure 3). Under suspicion of dysphagia due to CN dysfunction, she was referred to the rehabilitation department for ST, and was discharged from the hospital.

Figure 3 Nasopharyngoscopic image, showing salivary stasis in both pyriform sinuses, especially on the left side

General physical examination of the patient’s face conducted in our outpatient clinic showed normal results. A surgical suture line on the left side of her neck was found. Comprehension was normal. CN examination revealed mild dysarthria and dysphonia, dysphagia resulting in nasal regurgitation and cough after the patient swallowed, weakness of the left pharyngeal wall with mild deviation toward the right, the tongue slightly deviated toward the left during protrusion, and suspected paralysis of CNs IX, X, and XII. Clinical BSE demonstrated oropharyngeal dysphagia (Table 1). She could not pass the 100-mL water test and was at level 1 of the FOIS.

Traditional ST methods were used, including oral exercise, position adjustment (by turning the head to the left) in order to close the weak pharynx, swallowing maneuvers, and diet modification. Since no improvements were noted after 2 weeks (4 sessions), we decided to add NMES to traditional ST.

The Intelect VitalStim NMES machine (Chattanooga Group) was used (current model, discharge current; current intensity, 0-25 mA; pulse period, 100-300 μs; pulse rate, 80 pps). Two electrodes were placed in a vertical line on the right side of the neck, lateral to the midline, with channels 1 and 2 just above and below the thyroid nodes, respectively. The current intensity was such that the patient felt a “grabbing sensation,” indicating that the correct level of motor contraction had been reached. The stimulator was left at this level, and then ST was initiated. The patient had two 1-h training sessions each week.

Author’s contributions
The roles of the authors in this case report are as follows: FCL – first author, manuscript writing; F.Y.L. – The patient’s surgeon, providing the patient’s source and data; X.R.D. – The patient’s speech therapist, providing the swallowing training to the patient; C.P.L. – corresponding author, management of the study. All authors read and approved the final manuscript.

Acknowledgements
We would like to thank Department of Physical Medicine and Rehabilitation of Kaohsiung Chang Gung Memorial Hospital for their assistance with treatment place and materials.

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