Hemisensory Syndrome

Hemisensory syndrome refers to having an altered sensation on one side of the body. There is no weakness, homonymous hemianopia, aphasia, agnosia, or apraxia. A related concept is nondermatomal somatosensory deficits (NDSD) which refer to regional, hemibody, or quadratomal sensory changes.Egloff N, Sabbioni ME, Salathé C, Wiest R, Juengling FD. Nondermatomal somatosensory deficits in patients with chronic pain disorder: clinical findings and hypometabolic pattern in FDG-PET. Pain. 2009 Sep;145(1-2):252-8. doi: 10.1016/j.pain.2009.04.016. Epub 2009 Jun 4. PMID: 19500908. NDSDs are common in patients with widespread chronic pain.Mailis A, Papagapiou M, Umana M, Cohodarevic T, Nowak J, Nicholson K. Unexplainable nondermatomal somatosensory deficits in patients with chronic nonmalignant pain in the context of litigation/compensation: a role for involvement of central factors? J Rheumatol. 2001 Jun;28(6):1385-93. PMID: 11409135.
==Classification==
Complete hemisensory syndrome: affects the entire face, arm, and leg. The trunk may or may not be involved.
Incomplete hemisensory syndrome: includes variants such as cheiro-oral-cural syndrome, cheiro-oral syndrome, and isolated oral syndrome.
==Aetiology and Associations==
*Idiopathic (the most common)
*Migraine
*Depression and anxiety
*Nociplastic pain states such as CRPSRommel O, Gehling M, Dertwinkel R, Witscher K, Zenz M, Malin JP, Jänig W. Hemisensory impairment in patients with complex regional pain syndrome. Pain. 1999 Mar;80(1-2):95-101. doi: 10.1016/s0304-3959(98)00202-4. PMID: 10204721.Drummond PD, Finch PM, Birklein F, Stanton-Hicks M, Knudsen LF. Hemisensory disturbances in patients with complex regional pain syndrome. Pain. 2018 Sep;159(9):1824-1832. doi: 10.1097/j.pain.0000000000001280. PMID: 29787471.Drummond PD, Vo L, Finch PM. The Source of Hemisensory Disturbances in Complex Regional Pain Syndrome. Clin J Pain. 2021 Feb 1;37(2):79-85. doi: 10.1097/AJP.0000000000000893. PMID: 33136610., and Fibromyalgiada Silva LA, Kazyiama HH, Teixeira MJ, de Siqueira SR. Quantitative sensory testing in fibromyalgia and hemisensory syndrome: comparison with controls. Rheumatol Int. 2013 Aug;33(8):2009-17. doi: 10.1007/s00296-013-2675-6. Epub 2013 Feb 3. PMID: 23377531.. Can be increased sensitivity i.e. allodynia on the ipsilateral side rather than decreased.
*Myaesthenia gravis (case report)Marshall B, Sharma U, Benes-Lima L, Rossi FH. Hemisensory loss in myasthenia gravis. BMJ Case Rep. 2021 Mar 17;14(3):e237405. doi: 10.1136/bcr-2020-237405. PMID: 33731400; PMCID: PMC7978066
*Carpal tunnel syndrome (single case)
*Pure sensory strokes
**Thalamus: ventral posterior nucleus which interconnects with the primary somatosensory cortex. e.g. Dé​jerine-Roussy syndrome
**Internal capsule: posterior quarter of the posterior limb where the sensory tracts without motor fibres are found.
**Parietal lobe
**Corona radiata
**Pons: paramedian dorsolateral region
==Clinical Features==
Symptoms can be positive and/or negative. Positive symptoms are the presence of paraesthesias or dysaesthesias such as pins and needles, pricking, tightening, or burning. Negative symptoms are anaesthesia or hypoaesthesia.
In non-organic disease there is often an exact splitting at the midline. Organic disease can also have this pattern, however typically there is a paramedian distribution in this setting due to overlap of the intercostal nerves by 1-2cm. A classic sign of a non-organic aetiology is loss of vibration sense over one side of the sternum.
Strokes of the ventral posterior nucleus is associated with contralateral hemisensory deficit involve mechanical, temperature, and noxious sensations.
In patients with chronic pain-related NDSD there is subtle ipsilateral hyposensitivity to touch and temperature, mild to moderate depression, and a history of prolonged severe emotional distress. The symptoms are generally stable over time.
==Imaging==
The standard modality is MRI brain which should include diffusion weighted images. An attenuation of apparent diffusion coefficent is consistent with ischaemic stroke.
Stroke was the cause for 3% in one study,, and 22% in another study. In the later study, symptom onset of under 24 hours was the strongest predictor of ischaemic stroke (OR 31.4). A history of smoking (OR 7.3) and to a lesser extent older age (OR 1.14) was also more common in those with ischaemic stroke.
==References==
Category:Neurology