Hypertrophic Olivary Degeneration and Holmes Tremor: Case Report and Review of the Literature

[A case of Holmes tremor in which 123I-IMP SPECT and MRI findings suggest damage to the cerebellothalamic tract and the dentato-rubro-olivary pathway]

A 75-year-old woman was referred to our department in October 2022 with ataxia and involuntary movements of the right upper and lower limbs. She had experienced a left pontine hemorrhage in March 2021, which was managed conservatively. However, she had residual right-sided hemiplegia. In addition, she had cerebellar ataxia and a 2 ‍Hz resting tremor of the right upper and lower limbs, which was enhanced while maintaining posture and contemplation. Based on her history, and the findings of MRI and nuclear medicine imaging, we diagnosed the patient with Holmes tremor due to pontine hemorrhage. Holmes tremor is a rare movement disorder secondary to brainstem and thalamic lesions, characterized by a unilateral low-frequency tremor. In this case, 123I-IMP SPECT and MRI shows damage to the cerebellothalamic tract and dentaro-rubro-olivary pathway.

Cerebellar cognitive affective syndrome with psychotic features in a patient with hypertrophic olivary degeneration

Objective: Hypertrophic Olivary Degeneration is a rare condition causing transneuronal degeneration of the inferior olivary nucleus. Symptoms manifest as progressively worsening palatal tremor, ataxia, and eye movement disturbances that plateau after several months. Though rarely documented in the literature of this specific condition, disconnection of the inferior olivary nucleus from the cerebellum, and cerebellar atrophy represent a pathway to developing subsequent cerebellar cognitive affective syndrome. The presented case documents the neuropsychological sequelae of a 39-year-old female with a history of hypertrophic olivary degeneration and symptoms of palatal tremor, opsoclonus myoclonus, ataxia, and delusions. Method: Review of the patient's medical records, interviews with the patient and her father, and a neuropsychological assessment battery were used to collect data. Review of currently published literature lent to case conceptualization. Results: Neuropsychological testing revealed deficits in executive functioning, attention, and language. An anomalous, fixed persecutory delusion was revealed. Conclusion: Hypertrophic olivary degeneration creates disconnection syndromes between the inferior olivary nucleus, red nucleus, and cerebellum. Late stages of the disorder cause atrophy of the inferior olivary nucleus and adjacent structures. While the motor sequela is well documented, the neuropsychological and psychiatric impact is infrequently discussed in existing literature. We present the first case to detail the neuropsychological sequelae of hypertrophic olivary degeneration and propose a mechanism for the development of cognitive impairment and psychotic features within this condition.

Bilateral Hypertrophic Olivary Degeneration after Pontine Hemorrhage: A Case Report

BACKGROUND

Hemorrhage lesions may lead to bilateral hypertrophic olivary degeneration (HOD) through interruption of the dentato-rubral-olivary pathway. The pathological features of HOD are unusual neuronal trans-synaptic degenerative changes.

CASE SUMMARY

A 56-year-old female was admitted to our hospital because her lower extremities and left upper ones were unable to move for 3 mo, and the swelling of her right lower extremities became worse 3 days ago. She had a hypertension history. Her characteristic clinical manifestations are palatal myoclonus and nystagmus. The patient’s magnetic resonance imaging (MRI) results showed that she had bilateral HOD after an acute pontine hemorrhage. She was given symptomatic and supportive treatment. The gabapentin, the memantine and the trihexyphenidyl were taken twice a day each. The rehabilitation and psychotherapy were implemented. After 3 months of treatment, her eye symptoms improved.

CONCLUSION

Bilateral HOD is a rare phenomenon after pontine hemorrhage. The key to diagnosis lies in the clinical manifestations and MRI results.