Adjunctive Effect of Photobiomodulation Therapy with Nd:YAG Laser in the Treatment of Inferior Alveolar Nerve Paresthesia

Background: Disruption of peripheral branches of the trigeminal nerve in the field of maxillofacial surgery is a known risk due to the close connection of these branches with the bony structures of the maxilla and mandible. As a result, injuries of the lingual nerve and inferior alveolar nerve take place within routine maxillofacial surgery procedures, including local anesthetic injection, wisdom tooth surgery, and dental implant placement, resulting in paresthesia and dysesthesia. During the last three decades, low-level lasers (LLL) have been frequently used in various medical fields. Lately, this application has increased in several sectors. Methods and materials: This experiment was designed to explore the effect of low-level laser therapy (LLLT) with Nd:YAG on the paresthesia and dysesthesia of the lower lip. This ethics committee of Tbzmed, Tabriz, Iran, proved the present experiment with ethical code: IR.TBZMED.REC.1401.839. Results: After completing 10 sessions of laser therapy for the case group consisting of 25 patients with lower lip anesthesia, the visual analog scale index results revealed that following six sessions of laser therapy, a significant difference appeared in contrast to the control group. Also, according to the two-point tests, significant difference among the experimental and the control group appeared after ninth session of the laser therapy. Conclusions: Altogether, these data suggested LLLT with Nd:YAG as an effective treatment option for decreasing the anesthesia of the lower lip.

Spongy Scalp Swelling in a Middle-Aged Female: A Case Report of Lipedematous Scalp

Lipedematous scalp is a rare cutaneous disorder, characterized by subtle but conspicuous scalp swelling, usually associated with dysesthesia. The chronic recalcitrant nature of this condition can be extremely debilitating for the patient. We report a case of boggy scalp swelling and dysesthesia in a 37‑year‑old female present for five years. Magnetic resonance imaging (MRI) brain showed thickening of subcutaneous tissue of the scalp. Histopathological examination revealed thickened and edematous subcutaneous tissue, reaching up to the upper dermis. A diagnosis of lipedematous scalp was made. The patient was reassured about the benign nature of the disease and given symptomatic treatment for dysesthesia. Herein we discuss the approach to a case of boggy dysesthetic scalp swelling and the available treatment options.

Stroke-Induced Central Pain: Overview of the Mechanisms, Management, and Emerging Targets of Central Post-Stroke Pain

The incidence of stroke plays the foremost role in the genesis of central neuropathic pain. Central post-stroke pain (CPSP) is a central pain arising from a vascular lesion in the central nervous system that elicits somatosensory deficits, often contralateral to stroke lesions. It is expressed as continuous or intermittent pain accompanied by sensory abnormalities like dysesthesia and allodynia. CPSP remains de-emphasized due to the variation in onset and diversity in symptoms, besides the difficulty of distinguishing it from other post-stroke pains, often referred to as a diagnosis of exclusion. Spinothalamic dysfunction, disinhibition of the medial thalamus, and neuronal hyperexcitability combined with deafferentation in thalamocortical regions are the mechanisms underlying central pain, which play a significant role in the pathogenesis of CPSP. The treatment regimen for CPSP seems to be perplexed in nature; however, based on available studies, amitriptyline and lamotrigine are denoted as first-line medications and non-pharmacological choices may be accounted for cases intractable to pharmacotherapy. This review attempts to provide an overview of the mechanisms, existing management approaches, and emerging targets of CPSP. A profound understanding of CPSP aids in optimizing the quality of life among stroke sufferers and facilitates further research to develop newer therapeutic agents for managing CPSP.

Evaluation and Management of the Dysesthetic Patient

Dysesthesia is symptomatology that includes, but is not limited to, sensations of pain, burning, crawling, biting, numbness, piercing, pulling, cold, shock-like, pulling, wetness, and heat. These sensations can cause significant emotional distress and functional impairment in affected individuals. While some cases of dysesthesias are secondary to organic etiologies, most cases exist without an identifiable infectious, inflammatory, autoimmune, metabolic, or neoplastic process. Ongoing vigilance is required for concurrent or evolving processes, including paraneoplastic presentations. Elusive etiologies, unclear treatment regimens, and stigmata leave patients and clinicians with a difficult path forward marked by "doctor shopping," lack of treatment, and significant psychosocial distress. We addresses this symptomatology and the psychosocial burden that often comes with it. Although notoriously labeled as "difficult to treat," dysesthesia patients can be effectively managed, making life-changing relief possible for patients.

Treatment of unexplained facial numbness with stellate ganglion blockade: A case report

To date, there is no established treatment for facial numbness or dysesthesia of unspecified causes. Herein, we report a case of unexplained facial numbness and confirmed hypesthesia that achieved clinical response to stellate ganglion blockade (SGB). SGB might be an effective treatment of psychological stress-related facial numbness of unknown origin.

Trichoscopic Diagnosis and Management of a Case of Scalp Dysesthesia with Lichen Simplex Chronicus

Scalp dysesthesia (SD), a variant of cutaneous dysesthesia syndrome is an underrecognized cause of scalp pruritus. It usually presents with itch, pain, burning, or stinging sensation over localized or diffuse area of the scalp without any objective findings. Trichoscopy, a rapid and in-office procedure, could aid in the early clinical diagnosis of this condition and initiate management. We report a case of SD in an elderly male diagnosed with the aid of trichoscope, evaluated and treated successfully.

Punctate Administration of Ficin as a Human and Animal Model of Non-Histaminergic Itch

BACKGROUND

Ficin, a cysteine protease derived from fig-tree latex, has been reported to elicit itch and nociceptive sensations, though quantitative sensory studies are lacking. Cowhage containing the pruritic cysteine Mucunain, on the other hand, has been widely studied as activating polymodal nociceptors and eliciting a histamine-independent itch.

OBJECTIVES

We tested whether ficin in heat-inactivated cowhage spicules would elicit itch and nociceptive sensations in humans, and analogous behaviors in mice, that are similar to those evoked by native cowhage and, whether these behaviors in mice were dose-dependent when ficin was injected intradermally.

METHODS

Human volunteers rated the magnitude of itch and nociceptive sensations evoked by either native cowhage spicules or heat-inactivated spicules soaked in 1, 10 or 100 mg/ml ficin (0.03, 0.3, and 3 ng of ficin in spicule tip), applied to forearm. In mice, itch-like scratching and nociceptive-like wiping were recorded in response to either native cowhage, to heat-inactivated spicules that were either inactive or contained 100 mg/ml ficin, or to intradermal injections of 1.25, 2.5, or 5 μg/ 5 μl, each treatment applied to the cheek.

RESULTS

The dose of 100 mg/ml ficin in spicules evoked comparable magnitudes of itch, nociceptive sensations and areas of cutaneous dysesthesia as native cowhage in humans and comparable itch-like scratching and pain-like wiping behaviors in mice. But to elicit similar behaviors when injected intradermally in mice a greater amount of ficin (1.25 μg) was required.

CONCLUSION

Spicule-delivery or intradermal injection of ficin elicits behaviors in mice that model itch and nociceptive sensations in humans, suggesting that ficin may be useful in translating mechanistic research on the neural mechanisms of pruritic and nociceptive effects of cysteine proteases between the two species.

Scalp dysesthesia: a neuropathic phenomenon

Scalp dysesthesia is an abnormal sensation of the scalp in the absence of cutaneous disease. It is characterized by a burning and/or itching sensation and can be related to a variety of neurogenic or psychogenic causes. This condition is extremely bothersome and is also common- especially amongst the geriatric population, in women, in patients with diabetes mellitus and patients with psychiatric history. However, despite its prevalence in many populations, there is limited data about its causes and characteristics. Given its limited cutaneous manifestations it is also easily misdiagnosed and an underrecognized cause of scalp pruritus in the dermatological community. Therefore, education on scalp dysesthesia is paramount to helping physicians identify and provide appropriate treatment for these patients. This review focuses predominately on the neurogenic causes (with a brief review of psychogenic itch) of scalp dysesthesia and the therapeutics that have been found to be effective for this condition. Neurogenic causes of scalp dysesthesia occur with damage to the central or peripheral pathways of itch sensation, resulting in modification and heightened sensitivity of nerves that result in abnormal sensations in the absence of or out of proportion to external stimuli. A comprehensive review of etiologies is provided here, ranging from lesions to the central nervous system caused by cervical spine disease, trigeminal trophic syndrome, tumor, stroke, and multiple sclerosis, to small fiber neuropathies caused by diabetes, brow lifts, keloid and burn scarring. Recently, there have also been reports of scalp dysesthesias associated with post-infectious COVID-19. Treatment options tailored towards disease severity and different causes of disease will also be discussed. By elucidating the different mechanisms and therapeutic treatments of scalp dysesthesia, we hope to provide clinicians with the tools to identify and treat this condition as well as encourage further research into its etiologies and therapeutics.

Outcomes of bleb revision with ologen following filtering glaucoma surgery

PURPOSE

This study reports long-term outcomes of bleb revision with ologen™ Collagen Matrix (Aeon Astron Europe BV, the Netherlands) for the surgical management of various bleb-related issues including persistent bleb leaks with or without associated hypotony, bleb dysesthesia, overhanging blebs, or hypotony after filtering glaucoma surgery.

MATERIALS AND METHODS

A retrospective chart review was performed for patients who underwent ologen bleb revision from 2012 to 2019 at Glaucoma Associates of Texas.

RESULTS

The study included 23 eyes of 22 patients undergoing bleb revision with the ologen implant. Mean age was 74.0 ± 11.3 years, 16 (69.6%) were female, and 13 (56.5%) were White. Indications for bleb revision included bleb leak (78.3%), dysesthesia (13.0%), and hypotony from an overfiltering bleb (8.7%). Mean preoperative intraocular pressure was 6.8 ± 4.1 mmHg and the number of medications was 0.3 ± 0.9. Median follow-up was 24 months (range: 12-84 months); all patients had at least 12 months of follow-up. At 1 year, mean intraocular pressure was 10.9 ± 4.6 mmHg on 0.2 ± 0.5 medications, and at last follow-up, mean intraocular pressure was 10.4 ± 3.6 mmHg on 0.3 ± 0.7 medications. Bleb morphology remained low, diffuse, and posterior. One patient developed kissing choroidal effusions requiring surgical drainage with subsequent stabilization of intraocular pressure and bleb function, and three patients required additional surgery due to persistent leaks or bleb failure; there were no other vision-threatening complications.

CONCLUSIONS

Use of the ologen implant during surgical bleb revision is a useful surgical technique that confers long-term improvements in bleb morphology and stability of function.

The Novel Technique of Uniportal Endoscopic Interlaminar Contralateral Approach for Coexisting L5-S1 Lateral Recess, Foraminal, and Extraforaminal Stenosis and Its Clinical Outcomes

BACKGROUND

Multifocal intra-and-extraspinal lumbar stenotic lesions could be decompressed with one endoscopic surgical approach, which has the advantages of functional structure preservation, technical efficacy, and safety.

METHODS

A retrospective study was performed on 48 patients who underwent uniportal endoscopic contralateral approach due to coexisting lateral recess, foraminal, and extraforaminal stenosis at the L5-S1 level. Foraminal stenosis grade and postoperative dysesthesia (POD) were analyzed. Visual analog scale (VAS) pain scores, modified Oswestry Disability Index (ODI) scores, and MacNab criteria for evaluating pain disability and response were analyzed.

RESULTS

The foraminal stenosis grade of the treated spinal levels was grade 1 (n = 16, 33%), grade 2 (n = 20, 42%), and grade 3 (n = 12, 25%). The rate of occurrence of POD grade 2 and above, which may be related to intraoperative dorsal root ganglion (DRG) retraction injury, was revealed to be 4.2% (two with grade 2, none with grade 3). The patients showed favorable clinical outcomes.

CONCLUSIONS

Uniportal endoscopic interlaminar contralateral approach is an effective procedure to resolve combined stenosis (lateral recess, foraminal, and extraforaminal region) with one surgical approach at the L5-S1 level. It may be a minimal DRG retracting and facet joint preserving procedure in foraminal and extraforaminal decompression.

Neuropathic Itch: Routes to Clinical Diagnosis

Neuropathic itch occurs due to damage of neurons of the peripheral or central nervous system. Several entities, including metabolic, neurodegenerative, orthopedic, infectious, autoimmune, malignant, and iatrogenic conditions, may affect the somatosensory system and induce neuropathic itch. Due to the complex nature of neuropathic itch, particularly concerning its clinical presentation and possible etiological factors, diagnostic work-up of this condition is challenging. A detailed medical history, especially in regard to the itch, and a comprehensive physical examination are relevant to detect characteristic signs and symptoms of neuropathic itch and to rule out other possible causes for chronic itch. Complementary diagnostic exams, especially laboratory tests, determination of the intraepidermal nerve fiber density via a skin biopsy and radiological examinations may be indicated to confirm the diagnosis of neuropathic itch and to identify underlying etiological factors. Functional assessments such as quantitative sensory testing, nerve conduction studies, evoked potentials, or microneurography may be considered in particular cases. This review article provides a comprehensive overview of the diagnostic work-up recommended for patients with neuropathic itch.

A Novel Modification of the Sagittal Split Osteotomy as an Access Osteotomy

Pathologies present in the central zone of the mandible are difficult to access, primarily because of the presence of the inferior alveolar nerve (IAN) and the need to remove a large corticocancellous component to reach the area of interest. Many times, this bony window is replaced as a free graft and there is complete resorption in the long term or even rejection of the graft causing a bony defect which can weaken the mandible. Furthermore, the damage to the IAN is profound. To try and avoid these comorbidities the traditional sagittal split osteotomy was modified to access a central osteoma impinging on the IAN and the successful removal of the same without any comorbidities such as paraesthesia or loss of bone structure. We believe that this modification can be used for other scenarios such as benign cysts and difficult presentations of impacted teeth.

Paroxysmal Symptoms in Multiple Sclerosis-A Review of the Literature

Paroxysmal symptoms are well-recognized manifestations of multiple sclerosis (MS). These are characterized by multiple, brief, sudden onset, and stereotyped episodes. They manifest as motor, sensory, visual, brainstem, and autonomic symptoms. When occurring in the setting of an established MS, the diagnosis is relatively straightforward. Conversely, the diagnosis is significantly more challenging when they occur as the initial manifestation of MS. The aim of this review is to summarize the various forms of paroxysmal symptoms reported in MS, with emphasis on the clinical features, radiological findings and treatment options.

[Roles of TRPA1 in Painful Dysesthesia]

Dysesthesia is an unpleasant abnormal sensation, often accompanied by pain, paresthesia (abnormal sensation), and numbness (decrease or loss of sensation). Dysesthesia has been associated with various conditions, although its underlying mechanisms are largely unknown. This study assessed the roles of transient receptor potential ankyrin 1 (TRPA1) in dysesthesia by utilizing three animal models of dysesthesia characterized by reductions in blood flow to the skin: a transient hindlimb ischemia/reperfusion model, characterized by spontaneous licking and tactile hypoesthesia of the ischemic hindpaw; a streptozotocin-induced diabetic neuropathy model in mice, characterized by cold hypersensitivity, which is likely parallel to the reduced skin blood flow of the hindpaw; and a hindlimb ischemia model. TRPA1 inhibition or deficiency blocked spontaneous licking in the transient hindlimb ischemia/reperfusion model and cold hypersensitivity in the diabetic mouse model mice. Consistent with these results, the nocifensive behaviors induced by intraplantar injection of a TRPA1 agonist were enhanced in the diabetic neuropathy and hindlimb ischemia models. Hypoxia enhanced H₂O₂-induced TRPA1 responses in human TRPA1-expressing cells and cultured mouse dorsal root ganglion neurons, with this hypoxia-induced TRPA1 sensitization to H₂O₂ being associated with hypoxia-induced inhibition of the hydroxylation of prolyl hydroxylases. These results suggest that dysesthesia following blood flow reduction is caused by the activation of TRPA1 sensitized by hypoxia and that hypoxia-induced TRPA1 sensitization plays a pivotal role in painful dysesthesia induced by peripheral blood flow reduction.

Preoperative imaging findings as predictors of postoperative inferior alveolar nerve injury following mandibular cyst surgery

The purpose of the present study was to predict inferior alveolar nerve (IAN) exposure and associated neurosensory deficits after mandibular cyst surgery based on imaging findings. The study includes 193 sites in 184 consecutive patients who underwent enucleation of cystic lesions around a mandibular third molar (MM3) and extraction of the associated MM3. Absence/presence of white lines on panoramic radiographs (PR) and absence/presence of cortication surrounding the mandibular canal on computed tomography (CT) are evaluated as predictor variables. Outcome variables are operative IAN exposure and postoperative lower lip and/or chin dysesthesia. There is a significant correlation between interruption of white lines and loss of cortication. The predictor variables are statistically associated with IAN exposure and dysesthesia. Positive predictive values of CT findings (loss of cortication) for each outcome variable are slightly higher than those of PR findings (interruption of white lines). When considering the variables, type IV, with interruption of white lines and loss of cortication, shows a statistically significant difference compared to the other groups. White lines on PR images and cortication status of the mandibular canal on CT images predict operative IAN exposure and postoperative dysesthesia in mandibular cyst surgery.

Dysesthesia symptoms produced by sensorimotor incongruence in healthy volunteers: an electroencephalogram study

Objectives

Pathological pain such as phantom limb pain is caused by sensorimotor incongruence. Several studies with healthy participants have clearly indicated that dysesthesia, which is similar to pathological pain, is caused by incongruence between proprioception and/or motor intention and visual feedback. It is not clear to what extent dysesthesia may be caused by incongruence between motor intention and visual feedback or by incongruence between proprioception and visual feedback. The aim of this study was to clarify the neurophysiology of these factors by analyzing electroencephalograms (EEGs).

Methods

In total, 18 healthy participants were recruited for this study. Participants were asked to perform repetitive flexion/extension exercises with their elbows in a congruent/incongruent position while viewing the activity in a mirror. EEGs were performed to determine cortical activation during sensorimotor congruence and incongruence.

Results

In the high-frequency alpha band (10–12 Hz), numeric rating scale scores of a feeling of peculiarity were significantly correlated with event-related desynchronization/synchronization under the incongruence and proprioception conditions associated with motor intention and visual feedback (right inferior parietal region; r=−0.63, P<0.01) and between proprioception and visual feedback (right temporoparietal region; r=−0.49 and r=−0.50, P<0.05). In these brain regions, there was a region in which incongruence between proprioception and visual feedback and between motor intention and visual feedback caused an increase in activity.

Conclusion

The present findings suggest that neural mechanisms of dysesthesia are caused by incongruence between proprioception associated with motor intention and visual feedback and, in particular, are a result of incongruence between proprioception only and visual feedback.

[The impairment of A-delta fibers in median nerve compression at the wrist, using the cutaneous silent period]

Carpal tunnel síndrome (CTS) is an entrapment neuropathy of the median nerve at the wrist, that leads to pain, paresthesia and painful dysesthesia. The electrophysiological diagnosis is based upon nerve conduction studies which evaluate thick nerve fibers. Our hypothesis is that there is an additional dysfunction of small fibers in CTS, which correlates with the degree of severity of the neuropathy. A retrospective study of 69 hands that belonged to 47 patients of both sexes (mean age 53.8, years, range 22-87) was performed, and, as a control group, 21 hands which corresponded to the asymptomatic side of those patients were evaluated. Motor and sensory conduction studies, as well as F-waves were performed to classify the neuropathy according to the degree of severity. Cutaneous silent period (CSP) was elicited in all hands. Mean onset latencies and durations of CSP were evaluated. Mean onset latencies were significantly prolonged in neuropathic hands (84.3 ± 16.3 msec) compared to asymptomatic hands (74.8 ± 11.6 msec) (p < 0.05). Mean latencies of the CSP were even prolonged (p < 0.05) in hands affected by a more severe neuropathy. In the 3 hands with most severe neuropathy, a CSP could not be elicited. In CTS an impairment of A-delta fibers was recorded through the CSP. The more severe the neuropathy is, the more impairment of A-delta fibers can be found. CSP may be assessed as a complement of motor and sensory nerve conduction studies in this neuropathy.

Dural Arteriovenous Fistula of the Transverse and Sigmoid Sinus Manifesting Ascending Dysesthesia: Case Report and Literature Review

Cases involving intracranial dural arteriovenous fistulas (AVFs) with spinal perimedullary venous drainage exhibit variable presentations, which results in delayed diagnoses. We describe a case of a 66-year-old female with a transverse-sigmoid sinus dural AVF with spinal perimedullary venous drainage who developed dysesthesia and hypalgesia that ascended from the peripheral lower extremities. Sixty cases of intracranial dural AVFs resulting in myelopathy have been reported, and an absence of brainstem signs significantly correlated with a delay in diagnosis (positive group: 3.4 months vs. negative group: 9.6 months, P < 0.05). Intracranial dural AVFs with brainstem signs should be diagnosed without delay because the myelopathy and bulbar symptoms could progress aggressively without alternative drainage routes besides the perimedullary veins. We emphasize that intracranial dural AVFs should be considered as a differential diagnosis in case presenting with symptoms, such as atypical dysesthesia and hypalgesia ascending from the toes, without brainstem signs. Moreover, we should perform cerebral angiography as early as possible because dural AVFs with slow-flow venous drainage can produce false negatives on magnetic resonance angiography.

Photoletter to the editor: A neurocutaneous rarity: phacomatosis pigmentokeratotica

Phacomatosis pigmentokeratotica is characterized by the coexistence of nevus sebaceus, papular nevus spilus and associated neurologic abnormalities. We report a case of phacomatosis pigmentokeratotica in a 28-year-old male who presented with palmar-plantar dysesthesia and ipsilateral brain hemiatrophy. As a characteristic neuroimaging finding of the disorder, we found multiple hypointense lesions involving the ipsilateral hemisphere.

Neurotropic T-cell lymphocytosis: a cutaneous expression of CLIPPERS

Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is an inflammatory disease of the central nervous system that predominantly involves the pons and cerebellum and that improves with immunosuppressive treatment. Only recently described, the etiology is unknown, diagnosis is difficult and long-term neurological sequelae may occur without aggressive treatment. Herein, we describe a 59-year-old woman who presented with subcutaneous nodules affecting her face, trunk, limbs and an indurated annular erythematous lesion on her forearm. This was associated with marked dysesthesia of her skin, refractory to treatment. There was a 4-year history of dysequilibrium, vertigo, truncal and gait ataxia with progressive neurological symptoms. Skin biopsy of the annular nodular lesion showed a lymphohistiocytic infiltrate in dermis and subcutis with a striking lymphocyte-dominant infiltrate that was perineural and formed a nodular collection extending along a prominent subcutaneous nerve. Immunophenotyping indicated a marked predominance of T cells that were CD3 positive with a 2 : 1 CD4 : CD8 ratio. Scattered histiocytes were present but no well-formed granulomas or vasculitis. Magnetic resonance imaging studies showed changes in the pontine, brain stem and cerebellar region, which subsequently were defined as characteristic for CLIPPERS, but no brain biopsy was pursued. The marked neural skin symptoms and the cutaneous histopathological findings indicate that the skin may be an additional target organ in CLIPPERS, and the immune response may be directed against a common neural antigen. In radiologically typical CLIPPERS, identification of clinical skin lesions particularly subcutaneous nodules and biopsy may potentially form a basis for tissue diagnosis in this syndrome.

Genome-wide association study of sensory disturbances in the inferior alveolar nerve after bilateral sagittal split ramus osteotomy

BACKGROUND

Bilateral sagittal split ramus osteotomy (BSSRO) is a common orthognatic surgical procedure. Sensory disturbances in the inferior alveolar nerve, including hypoesthesia and dysesthesia, are frequently observed after BSSRO, even without distinct nerve injury. The mechanisms that underlie individual differences in the vulnerability to sensory disturbances have not yet been elucidated.

METHODS

The present study investigated the relationships between genetic polymorphisms and the vulnerability to sensory disturbances after BSSRO in a genome-wide association study (GWAS). A total of 304 and 303 patients who underwent BSSRO were included in the analyses of hypoesthesia and dysesthesia, respectively. Hypoesthesia was evaluated using the tactile test 1 week after surgery. Dysesthesia was evaluated by interview 4 weeks after surgery. Whole-genome genotyping was conducted using Illumina BeadChips including approximately 300,000 polymorphism markers.

RESULTS

Hypoesthesia and dysesthesia occurred in 51 (16.8%) and 149 (49.2%) subjects, respectively. Significant associations were not observed between the clinical data (i.e., age, sex, body weight, body height, loss of blood volume, migration length of bone fragments, nerve exposure, duration of anesthesia, and duration of surgery) and the frequencies of hypoesthesia and dysesthesia. Significant associations were found between hypoesthesia and the rs502281 polymorphism (recessive model: combined χ² = 24.72, nominal P = 6.633 × 10⁻⁷), between hypoesthesia and the rs2063640 polymorphism (recessive model: combined χ² = 23.07, nominal P = 1.563 × 10⁻⁶), and between dysesthesia and the nonsynonymous rs2677879 polymorphism (trend model: combined χ² = 16.56, nominal P = 4.722 × 10⁻⁵; dominant model: combined χ² = 16.31, nominal P = 5.369 × 10⁻⁵). The rs502281 and rs2063640 polymorphisms were located in the flanking region of the ARID1B and ZPLD1 genes on chromosomes 6 and 3, whose official names are "AT rich interactive domain 1B (SWI1-like)" and "zona pellucida-like domain containing 1", respectively. The rs2677879 polymorphism is located in the METTL4 gene on chromosome 18, whose official name is "methyltransferase like 4".

CONCLUSIONS

The GWAS of sensory disturbances after BSSRO revealed associations between genetic polymorphisms located in the flanking region of the ARID1B and ZPLD1 genes and hypoesthesia and between a nonsynonymous genetic polymorphism in the METTL4 gene and dysesthesia.