Painful Tic Convulsif Syndrome (PTCS) is a rare syndrome in which trigeminal neuralgia (TN) and ipsilateral hemifacial spasm (HS) coexist. It is considered a debilitating disease that significantly reduces patients’ quality of life.
History: The term “painful tic convulsif” was coined by Cushing in 1920. The association between TN and HS was identified by Campbell & Keedy in 1947. In recent years, Liu et al. published a retrospective study of 40 cases in 2020, and Yin et al. published the first individual patient data meta-analysis accumulating 192 cases in 2021, clarifying epidemiological characteristics and relative frequencies of etiologies.
Epidemiology: It predominantly occurs in women aged 40–60 years and is more common on the left side. The frequency of trigeminal neuralgia itself is 4–5 per 100,000 people, more common in elderly women, while hemifacial spasm is more common in middle-aged and elderly individuals and follows a chronic progressive course. According to Liu et al., PTCS often presents initially as HS, and aging correlates with recurrence rates.
It is an extremely rare disease, with only 192 cases accumulated in the meta-analysis by Yin et al. in 2021. Most reports are case reports or small case series, and large-scale epidemiological data are limited.
In PTCS, symptoms of trigeminal neuralgia and hemifacial spasm coexist in the same patient.
Symptoms of Trigeminal Neuralgia (TN):
Symptoms of hemifacial spasm (HS):
Characteristics of PTCS: According to Liu et al., HS occurs more frequently than TN as the initial symptom. The essential feature of PTCS is that both symptoms appear on the same side.
Ocular Findings (May appear but are not specific to PTCS):
HS-related findings:
Eye symptoms are not essential for the diagnosis of PTCS. The essence of diagnosis is the coexistence of TN and HS on the same side. However, an ophthalmologist may detect corneal hypoesthesia or involuntary eyelid contractions, which can trigger the diagnosis.
Vascular Compression (85%)
Main responsible vessels: Vertebral artery, basilar artery, anterior inferior cerebellar artery (AICA), posterior inferior cerebellar artery (PICA).
Example of unified pathology: Dilation of PICA may compress both the trigeminal and facial nerves simultaneously.
Tumors (8%)
Types: Meningioma, schwannoma, arachnoid cyst, skull bone abnormalities.
This is a rare cause, and data on treatment outcomes are limited.
Vascular diseases (5–6%)
Types: Aneurysm, venous malformation.
Treatment data for PTCS due to vascular disease are also limited, and further investigation is needed.
Risk factors for HS: arteriosclerosis, family history, facial nerve damage (Bell’s palsy, compression, trauma), facial trauma.
Risk factors for TN: arteriosclerosis, hypertension, trigeminal nerve damage (compression, trauma, infection), family history, aging, stress.
When the myelin-deficient area of the trigeminal nerve at its exit from the brainstem is compressed by blood vessels or tumors, hypersensitivity occurs, causing electric shock-like pain. HS occurs when the facial nerve or pons is compressed by blood vessels in the posterior cranial fossa.
The diagnosis of PTCS is confirmed by the simultaneous presence of TN and HS on the same side.
Diagnostic criteria for TN (3 criteria):
Diagnostic criteria for HS:
Major differential diagnoses are shown in the table below.
| Symptoms | Common misdiagnoses |
|---|---|
| Trigeminal neuralgia | Dental disease, sinusitis, migraine, cluster headache |
| Hemifacial spasm | Tic, psychogenic, blepharospasm (essential) |
Differentiation from other involuntary movements such as myokymia and fasciculations is also necessary. HS may go undiagnosed.
TN is often misdiagnosed as dental disease, sinusitis, or migraine, and HS as tics or psychogenic disorders. Furthermore, because the coexistence of both is not easily recognized, diagnosis as PTCS is often delayed. It is important to examine with the possibility that TN and HS coexist on the same side.
Treatment of trigeminal neuralgia:
Treatment of hemifacial spasm:
Microvascular decompression (MVD) is the standard surgical treatment for PTCS caused by vascular compression.
Other treatments: tumor/cyst resection, radiofrequency coagulation, thermocoagulation, gamma knife radiosurgery.
When vascular compression is the single cause, MVD can relieve compression of both the trigeminal and facial nerves at once. The cure rate is over 80%, and particularly good results are obtained when the AICA or PICA is the responsible vessel.
PTCS includes a “unified pathology” where a single lesion compresses both nerves simultaneously, and an “independent pathology” where separate lesions affect each nerve.
The transitional zone where the trigeminal nerve enters the pons (the transition from peripheral to central myelin) is vulnerable to demyelination.
The facial nerve root exit zone is covered only by arachnoid membrane and lacks an epineurium. It is a transition zone from central to peripheral myelin and lacks connective tissue septa, making it vulnerable to compression.
Example of unified pathology: Dilation of the PICA compresses both the trigeminal and facial nerves simultaneously.
Example of independent pathology: The AICA compresses the trigeminal nerve, and the facial nerve is damaged during brain surgery.
Liu et al. (2020) showed in a retrospective study of 40 cases that PTCS more often presents as HS than TN.
Yin et al. (2021) published the first individual patient data meta-analysis of 192 cases, systematically elucidating the epidemiological characteristics, relative frequency of etiologies, and risk factors of PTCS.
Data on treatment efficacy for rare causes (tumors, cysts, vascular diseases, trauma) are currently limited, and further research is needed. The possibility of underdiagnosis of PTCS has been pointed out, and education and awareness for accurate diagnosis of TN and HS are required.
Cushing H. The major trigeminal neuralgias and their surgical treatment. Am J Med Sci. 1920.
Campbell FG, Keedy C. Hemifacial spasm: a review of the etiologic factors, with emphasis on those originating from the central nervous system. Can Med Assoc J. 1947.
Liu C, et al. Hemifacial spasm combined with ipsilateral trigeminal neuralgia (painful tic convulsif): clinical and neuroimaging characteristics in 40 patients. Neurosurgery. 2020.
Yin LX, et al. Hemifacial spasm combined with ipsilateral trigeminal neuralgia: systematic review and individual patient data meta-analysis of 192 cases. J Neurosurg. 2021.
