A case report out of Italy published last month details the treatment of a patient using inhibitory rTMS of a high level visual processing center (the SPL). The report is paid access, so I've provided an AI summary.

Original Link

Case Overview & Patient Profile

An 18-year-old female presented with treatment-resistant Visual Snow Syndrome (VSS), alongside a history of migraine with aura and panic attacks. Standard diagnostics—including structural brain MRIs, optical coherence tomography (OCT), and visual evoked potentials (VEPs)—were entirely unremarkable.

Pharmacological trials with lamotrigine (25 mg BID) and topiramate (50 mg BID) failed to provide therapeutic relief and were stopped due to side effects (tremors and insomnia). FL-41 rose-tinted lenses successfully mitigated her photophobia (light sensitivity) but had zero impact on her visual static.

The rTMS Intervention Protocol

Because VSS is characterized by a hyper-excited visual network, clinicians used low-frequency repetitive Transcranial Magnetic Stimulation (rTMS) to induce local cortical inhibition.

The exact parameters utilized were:

• The Target: Bilateral Superior Parietal Lobule (SPL)—a high-level sensory integration hub. Real-time accuracy was ensured via an MRI/fMRI-guided neuronavigation system (Brainsight).
• Frequency & Intensity: 1-Hz (inhibitory) pulses set to 100% of the patient's Phosphene Threshold (PT)—the minimum magnetic energy required to trigger perceived flashes of light.
• Total Dosage: 10 consecutive daily sessions. Each session delivered 7,200 total pulses (3,600 per hemisphere).

Clinical and Neurophysiological Results

The treatment was well tolerated with no reported side effects. Following the 10-day protocol, data collected via patient self-reports, resting-state fMRI (rs-fMRI), and resting-state EEG (rs-EEG) revealed significant improvements:

1. Subjective Symptom Relief

Using standardized visual simulation software, the patient reported a 32% to 40% reduction in static dot density across all day and night testing environments. She also noted an increase in visual processing speed, though the physical grain size of the static remained unchanged.

2. Rising Phosphene Threshold (PT)

The patient’s PT rose steadily from 10% of maximum stimulator output on Day 1 to 15% on Day 10. This change confirmed that the magnetic pulses successfully lowered the overall baseline excitability of her visual system.

3. Rewired Brain Connectivity (fMRI)

Post-treatment rs-fMRI showed a marked decrease in functional connectivity between the treated SPL and the lingual gyrus (LG)—the deep occipital region known to be chronically hyperactive in VSS patients.

4. Quieted Brain Waves (EEG)

Spectral analysis of her rs-EEG showed a clear decrease in both low-gamma (30–48 Hz) and high-gamma (55–68 Hz) power across the parieto-occipital regions during both eyes-open and eyes-closed states. This confirmed a reduction in local, pathological brain wave synchronization.

Study Limitations: As a single case report lacking a sham (placebo) control or long-term follow-up data, further clinical trials are necessary to determine the long-term stability and durability of targeting the SPL hub.