Texture-Specific Pharyngeal Dystonia Identified in Rare Case Reports

For two months, a 28-year-old woman experienced dysphagia triggered exclusively by tomato sauce. Whether consumed alone or incorporated into other dishes, the sauce caused swallowing difficulty, yet chopped tomatoes and all other foods passed without issue. Extensive neurological, allergic, endoscopic, and imaging evaluations yielded normal results.

Italian researchers, led by neurologist Domenico A. Restivo, documented this case alongside a second patient presenting the inverse phenotype in Movement Disorders Clinical Practice (May 2025). They designated the condition food-consistency/texture-specific pharyngeal dystonia, classifying it as a novel form of focal task-specific dystonia. The defining characteristic is that the trigger appears to be the physical texture of the bolus, not the food substance itself.

Videofluoroscopy Reveals Texture-Dependent Motor Failure

Videofluoroscopic swallowing studies (VFSS) using various consistencies—thin liquid, semi-solid, solid, and chopped tomato—showed normal physiology. However, when the patient swallowed tomato sauce mixed with barium contrast, the study revealed pharyngeal residue and incomplete opening of the upper esophageal sphincter (UES). The oral preparatory phase remained intact.

On the Penetration-Aspiration Scale, the tomato sauce swallow scored 5 (material entering the airway after the swallow), whereas all other consistencies, including chopped tomato, scored 1 (normal). This distinction carries clinical significance, as airway invasion elevates the risk of aspiration pneumonia and choking, warranting comprehensive investigation even for a single-food complaint.

High-resolution manometry and electromyography corroborated the imaging findings. With chopped tomato, the inferior pharyngeal constrictor and cricopharyngeus muscles activated in normal sequence. With tomato sauce, coordination between these muscles disintegrated; the cricopharyngeus exhibited delayed and incomplete relaxation.

Mirror-Image Presentation in a Second Patient

A 23-year-old woman presented with a six-month history of dysphagia triggered solely by chopped pineapple, whether eaten alone or mixed. Pineapple juice and all other foods were tolerated normally. Her diagnostic workup mirrored the first case: normal VFSS and muscle recordings with pineapple juice, but discoordination of the same pharyngeal muscle pair and a Penetration-Aspiration Scale score of 4 with chopped pineapple. She also lacked any neurological or psychiatric history.

Juxtaposed, the cases demonstrate opposing texture sensitivities: one patient failed with a smooth puree but succeeded with solid chunks of the same fruit; the other failed with solid chunks but succeeded with the liquid form. The authors report this as the first documentation of pharyngeal dystonia driven by food consistency or texture rather than by a specific food item.

Targeted Botulinum Toxin Injection Restores Function

Pharyngeal dystonia causing dysphagia is exceedingly rare, distinct from the swallowing dysfunction commonly seen in Parkinson’s disease. Task-specific dystonias (e.g., writer’s cramp, musician’s dystonia) are thought to involve aberrant sensorimotor integration during highly practiced skilled movements. In these patients, the trigger was a sensory property—texture—rather than a motor skill.

Both women received 10 units of incobotulinumtoxinA injected into the cricopharyngeal muscle at a single site under electromyographic guidance, an off-label application. Dr. Restivo has utilized this technique since a 2002 report in the New England Journal of Medicine on cricopharyngeal injections for Parkinsonian dysphagia, and a 2017 multi-disorder cohort study co-authored by him demonstrated sustained benefit.

Within seven days, both patients swallowed their respective trigger foods safely. Repeat VFSS and EMG confirmed normalization of swallowing physiology. Clinical benefit persisted for approximately four months before symptom recurrence; subsequent reinjections restored normal function.

Clinical Implications and Outstanding Questions

As case reports, these findings leave fundamental questions unanswered: the neurobiological mechanism linking texture perception to pharyngeal motor patterning, the etiology in young adults without neurological comorbidities, and the specificity to a single food item. The authors hypothesize a malfunction in central circuits that modulate swallowing kinematics based on bolus rheology, but emphasize the mechanism remains unknown.

Critically, this condition is distinct from common food aversions, picky eating, or sensory processing sensitivities, which do not involve objective, measurable failure of pharyngeal muscle coordination.

The primary clinical takeaway is the necessity of testing the specific trigger food. In both patients, standard swallowing assessments using generic consistencies were normal; only the challenge with the specific texture elicited the pathophysiology. Clinicians should maintain a high index of suspicion for task-specific dystonia when patients report highly selective dysphagia, even if initial workups are unrevealing.

Persistent coughing or choking during meals, globus sensation, unexplained weight loss, or recurrent pulmonary infections warrant referral to a speech-language pathologist or otolaryngologist. Acute airway obstruction requires immediate emergency intervention.

Key Questions Answered

What occurred in the first case?

A 28-year-old woman developed dysphagia exclusively with tomato sauce; chopped tomatoes and all other foods were swallowed normally.

What did diagnostic testing reveal?

Pharyngeal manometry and VFSS demonstrated discoordination of the inferior pharyngeal constrictor and cricopharyngeus with incomplete UES relaxation, but only during tomato sauce swallows.

What characterized the second case?

A 23-year-old woman exhibited dysphagia solely with chopped pineapple; pineapple juice was tolerated. Objective testing was abnormal only with the solid fruit consistency.

What is pharyngeal dystonia?

An involuntary, poorly coordinated contraction of pharyngeal musculature during swallowing. The authors describe a novel subtype triggered by food texture.

How were the patients treated?

With a single-site, EMG-guided injection of 10 units of incobotulinumtoxinA into the cricopharyngeus. Both patients achieved safe swallowing of trigger foods within one week; effect duration was approximately four months.

Does a food texture aversion indicate this condition?

No. Food aversions and sensory sensitivities are common and distinct from the measurable neuromuscular discoordination documented here.

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