Sensory Restoration Research Articles

Neurotization of nasal mucosa by end-to-side nerve graft: preliminary report of smell restoration

Nerve regeneration after an end-to-side neurorrhaphy had been well established in the literature. Both sensory and motor functions could be achieved using this technique. Autonomic and special sensory restoration (e.g., smell sensation) were not studied extensively before. Post-traumatic anosmia has an overall prevalence rate of 7%, with a variable rate of recovery. In this preliminary report, olfactory sensation was restored in a case with a long-standing anosmia using end-to-side nerve graft. The patient reported regaining of smell, which was confirmed by a smell identification test. This technique has the potential to be a promising method for smell restoration; however, it needs further workup and investigations. Level of Evidence: Level V, therapeutic study.

Sifting through the Evidence: A Comprehensive Review and Analysis of Neurotization in Breast Reconstruction.

An untoward outcome following breast reconstruction is diminished or complete loss of sensation. As the reconstructive paradigm continues to evolve, sensory restoration following reconstruction remains a research focus. Despite the multitude of published outcomes, there is marked heterogeneity across studies, thus confounding published outcomes. This study critically appraises the literature to summarize outcomes and establish a framework to guide clinical practice and future research. A literature review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines in an effort to perform a meta-analysis. The Ovid MEDLINE, PubMed, Embase, Scopus, Cochrane, and ClinicalTrials.gov online databases were queried to capture all publications between 1990 and 2017 that investigated postreconstruction breast sensation. The primary outcome of interest was breast sensation following both implant-based and autologous reconstruction with or without neurotization. Secondary outcomes of interest included time to sensory testing and patient-reported outcomes. Overall, 503 titles were screened, from which 37 articles were ultimately included for analysis, accounting for 1299 patients. There was major methodologic variability and inconsistent measurable outcomes across studies. It can be deduced that postoperative sensation returns spontaneously and unpredictably, neurotization enhances the magnitude and rapidity of sensory restoration when compared to nonneurotized reconstruction, and a sensate reconstruction improves patient-reported outcomes. Significant study design discrepancies exist, making it difficult to combine data and assess results. To effectively study breast sensation and the impact of neurotization, future investigation will depend on standardizing the way in which breast sensation is measured.

Palmar Ulnar Artery Perforator Free Flap for Fingertip Reconstruction: Anatomical and Clinical Study.

Background Fingertips are a common site for hand injuries. The ideal substitute for fingertip pulp is tissue that matches texturally with minimal donor site morbidity. We described anatomical findings from cadaveric studies and the reliability of the palmar ulnar artery perforator (PUAP) free flap techniques for the reconstruction of fingertips injuries. Methods The cadaveric study involving 8 hands was conducted to illuminate the anatomy of the hypothenar region. We investigated the emerging point of perforators, diameter of the artery at the origin, and the length of the pedicle. Forty-four patients with fingertip injuries underwent fingertip reconstruction using PUAP free flaps. Data on the baseline patient demographics, hospital courses, and flap sizes were obtained retrospectively. The 6-month postoperative sensory capacity was determined using a 2-point discrimination test. Results The cadaveric study found that the PUAP pedicles arose from the superficial palmar arch, the mean length of pedicles, and the diameter and location of perforators were also analyzed. The PUAP flap sizes varied from 2.0 × 2.3 cm to 2.5 × 3.5 cm, and the mean operative time was 124 min. In all cases, we performed neurorrhaphy for fingertip sensory restoration. All donor sites were closed primarily, and the 2-point discrimination test result was 5.7 ± 0.87 mm 6 months after surgery. Conclusions We confirmed the anatomical consistency of the PUAP. Among the numerous reconstruction options available for fingertip injuries, the PUAP free flap is a useful fingertip reconstruction option.

Recovery of taste organs and sensory function after severe loss from Hedgehog/Smoothened inhibition with cancer drug sonidegib

Striking taste disturbances are reported in cancer patients treated with Hedgehog (HH)-pathway inhibitor drugs, including sonidegib (LDE225), which block the HH pathway effector Smoothened (SMO). We tested the potential for molecular, cellular, and functional recovery in mice from the severe disruption of taste-organ biology and taste sensation that follows HH/SMO signaling inhibition. Sonidegib treatment led to rapid loss of taste buds (TB) in both fungiform and circumvallate papillae, including disruption of TB progenitor-cell proliferation and differentiation. Effects were selective, sparing nontaste papillae. To confirm that taste-organ effects of sonidegib treatment result from HH/SMO signaling inhibition, we studied mice with conditional global or epithelium-specific Smo deletions and observed similar effects. During sonidegib treatment, chorda tympani nerve responses to lingual chemical stimulation were maintained at 10 d but were eliminated after 16 d, associated with nearly complete TB loss. Notably, responses to tactile or cold stimulus modalities were retained. Further, innervation, which was maintained in the papilla core throughout treatment, was not sufficient to sustain TB during HH/SMO inhibition. Importantly, treatment cessation led to rapid and complete restoration of taste responses within 14 d associated with morphologic recovery in about 55% of TB. However, although taste nerve responses were sustained, TB were not restored in all fungiform papillae even with prolonged recovery for several months. This study establishes a physiologic, selective requirement for HH/SMO signaling in taste homeostasis that includes potential for sensory restoration and can explain the temporal recovery after taste dysgeusia in patients treated with HH/SMO inhibitors.

Sensory recovery of myomucosal flap oral cavity reconstructions.

Sensory restoration of the oral cavity is a primary aim of reconstructive surgery in posttraumatic or postablative defects. Sensitivity plays a key role in oral function, whose impairment strongly affects the patient's quality of life. Cheek myomucosal flaps provide a reliable and tissue-like reconstruction of these regions but their sensitive recovery, which we still know little about, deserves thorough assessment. In this retrospective study, the myomucosal cheek flaps were tested for different aspects of sensory recovery: touch; 2-point discrimination; pain; sharp/smooth discrimination; ability to feel hot/cold stimulus; stereognosis; and taste. Fifty-two myomucosal flap reconstructions were investigated. All sensitivity tests showed positive results. When comparison was possible, sensitivity seemed significantly close to the contralateral healthy side. Sensory recovery proved to be even better than that reported on reinnervated microvascular free flap reconstructions of the oral cavity. Myomucosal flap reconstruction demonstrated a high degree of sensory recovery.

Comparing the sensation of common donor site regions for autologous breast reconstruction to that of a healthy breast

Autologous breast reconstruction has become the standard care for breast cancer patients. Although excellent cosmetic results can be achieved, most reconstructed breasts fail to regain normal sensation. Nerve coaptation of the flap has been suggested to improve sensation; the effect of the donor flap native sensory threshold on the degree of sensory restoration is yet to be determined. The aim of this study is to evaluate the differences in sensation between various potential donor site regions in comparison to the sensation of the healthy breast. A cross-sectional study in healthy women was performed in the Maastricht University Medical Centre. Monofilaments were used to measure sensation in the breast and at different flap donor sites: deep inferior epigastric perforator (DIEP), lateral thigh perforator (LTP), profunda artery perforator (PAP), superior gluteal artery perforator (SGAP) and transverse musculocutaneous gracilis (TMG) flaps. The Wilcoxon signed rank test was used to analyse statistical significance in sensation. Fifty women with a mean age of 49 ± 2.72 years and mean BMI of 26.14 ± 0.89 kg/m2 were included in the study. The median monofilament value of the normal breasts was 2.97(2.56-3.55). The median monofilament value of each donor site and p value when compared to the healthy breast were as follows: DIEP flap, 2.62 (2.36-3.22) p < 0.01; LTP flap, 3.61 (2.83-4.08) p <0.01; PAP flap, 3.09 (2.67-3.5) p = 0.97; SGAP flap, 3.22 (2.64-3.87) p = 0.01; and TMG flap, 3.03 (2.6-3.47) p = 0.69. There is a significant difference in sensation between the various donor site regions for breast reconstruction and the healthy breast. This may be taken into consideration for donor site selection.

Increased cross-modal functional connectivity in cochlear implant users

Previous studies have reported increased cross-modal auditory and visual cortical activation in cochlear implant (CI) users, suggesting cross-modal reorganization of both visual and auditory cortices in CI users as a consequence of sensory deprivation and restoration. How these processes affect the functional connectivity of the auditory and visual system in CI users is however unknown. We here investigated task-induced intra-modal functional connectivity between hemispheres for both visual and auditory cortices and cross-modal functional connectivity between visual and auditory cortices using functional near infrared spectroscopy in post-lingually deaf CI users and age-matched normal hearing controls. Compared to controls, CI users exhibited decreased intra-modal functional connectivity between hemispheres and increased cross-modal functional connectivity between visual and left auditory cortices for both visual and auditory stimulus processing. Importantly, the difference between cross-modal functional connectivity for visual and for auditory stimuli correlated with speech recognition outcome in CI users. Higher cross-modal connectivity for auditory than for visual stimuli was associated with better speech recognition abilities, pointing to a new pattern of functional reorganization that is related to successful hearing restoration with a CI.

Total lower lip and chin reconstruction with radial forearm free flap: A novel approach

BackgroundThe management of large chin and lower lip defects is challenging due to this facial subunit's tremendous functional and aesthetic importance. Specific methods for total lower lip and mentum reconstruction are not well chronicled. Aesthetic and functional goals of this reconstruction include restoration of oral competence by maintaining lower lip height, vermilion reestablishment, color-matched skin introduction to the chin, sensation restoration, and ideally restoration of dynamic activity to the lower lip. MethodsLiterature review performed. ResultsPresentation of novel, two-stage technique for lower lip and chin reconstruction with a submental flap and a radial forearm free flap, suspension of the lower lip and chin with a tensor fascia lata graft, and vermilion reconstruction with a buccal mucosal flap. ConclusionsThis procedure meets all goals of total lower lip reconstruction with the exception of the introduction of dynamic tissue and represents a novel solution to a challenging reconstructive problem.

Key considerations in designing a somatosensory neuroprosthesis

In recent years, a consensus has emerged that somatosensory feedback needs to be provided for upper limb neuroprostheses to be useful. An increasingly promising approach to sensory restoration is to electrically stimulate neurons along the somatosensory neuraxis to convey information about the state of the prosthetic limb and about contact with objects. To date, efforts toward artificial sensory feedback have consisted mainly of demonstrating that some sensory information could be conveyed using a small number of stimulation patterns, generally delivered through single electrodes. However impressive these achievements are, results from different studies are hard to compare, as each research team implements different stimulation patterns and tests the elicited sensations differently. A critical question is whether different stimulation strategies will generalize from contrived laboratory settings to activities of daily living. Here, we lay out some key specifications that an artificial somatosensory channel should meet, discuss how different approaches should be evaluated, and caution about looming challenges that the field of sensory restoration will face.

Clinical application of dorsal metacarpal artery composite flap for coverage of tendon and skin defects of the fingers

Objective To discuss the surgical techniques and treatment outcomes of one-stage repair of complex soft tissue and extensor tendon defect of the fingers by transferring dorsal metacarpal artery flap that includes extensor indicis proprius (extensor digiti minimi proprius) tendon and dorsal cutaneous nerve. Methods From April 2013 to September 2015, 6 cases of middle finger dorsal complex tissue defect were managed with dorsal metacarpal artery composite flap transfer for skin coverage, extensor tendon repair and sensory restoration. The flap size that covered these defects ranged from 6.0 cm×2.0 cm to 7.0 cm×3.0 cm.The donor site was directly closed.Passive functional exercise was initiate done one week postoperatively and lasted for 4 to 6 weeks. Results All 6 flaps survived completely. All the patients were follow-up for 3 to 13 months with an average of 8.2 months. Sensation of the flaps recovered to S3 level. Two-point discrimination was 7 to 10 mm while the mean value was 8.6 mm. The color, texture and contour of the flaps were good. Mobility of the hand was satisfactory. Conclusion Dorsal metacarpal artery composite flap transfer is a reliable way to cover complex tissue defects on the dorsum of fingers. It has consistent vascular anatomy, affords extensor tendon and cutaneous nerve reconstruction along with skin coverage, shortens treatment time, and improves outcomes without added risks. Key words: Surgical flaps; Finger injuries; Metacarpal artery; Compound tissue flap

Expression of an Activated Integrin Promotes Long-Distance Sensory Axon Regeneration in the Spinal Cord.

After CNS injury, axon regeneration is blocked by an inhibitory environment consisting of the highly upregulated tenascin-C and chondroitin sulfate proteoglycans (CSPGs). Tenascin-C promotes growth of axons if they express a tenascin-binding integrin, particularly α9β1. Additionally, integrins can be inactivated by CSPGs, and this inhibition can be overcome by the presence of a β1-binding integrin activator, kindlin-1. We examined the synergistic effect of α9 integrin and kindlin-1 on sensory axon regeneration in adult rat spinal cord after dorsal root crush and adeno-associated virus transgene expression in dorsal root ganglia. After 12 weeks, axons from C6-C7 dorsal root ganglia regenerated through the tenascin-C-rich dorsal root entry zone into the dorsal column up to C1 level and above (>25 mm axon length) through a normal pathway. Animals also showed anatomical and electrophysiological evidence of reconnection to the dorsal horn and behavioral recovery in mechanical pressure, thermal pain, and ladder-walking tasks. Expression of α9 integrin or kindlin-1 alone promoted much less regeneration and recovery. The study demonstrates that long-distance sensory axon regeneration over a normal pathway and with sensory and sensory-motor recovery can be achieved. This was achieved by expressing an integrin that recognizes tenascin-C, one of the components of glial scar tissue, and an integrin activator. This enabled extensive long-distance (>25 mm) regeneration of both myelinated and unmyelinated sensory axons with topographically correct connections in the spinal cord. The extent of growth and recovery we have seen would probably be clinically significant. Restoration of sensation to hands, perineum, and genitalia would be a significant improvement for a spinal cord-injured patient.

A comparative study of anterolateral thigh perforator flap with and without sensory nerve graft for sensation reconstruction in head and neck region

Objective To compare the operation effects of sensation restoration after tumor resection in the head and neck defects reconstruction by anterolateral thigh flap with or without sensory nerve transplantation. Methods The application of 76 cases anterolateral thigh flaps in head and neck defects reconstruction after tumor resection from May, 2011 to May, 2015 were observed. 35 patients underwent simultaneous reconstruction with sensory nerve anastomosed perforator based anterolateral thigh flap and 41 patients underwent simultaneous reconstruction without sensory nerve graft based anterolateral thigh flap, which was named as group A and group B, respectively. The treatment effectiveness of the two groups was compared and graded into First, Second and Third rate. Results All the 76 flaps survived. Satisfying morphology for the maxillofacial region and stage-one healing for the donor site was available. During the 24-week follow-up, group A were 65.71% (First rate) , 28.57% (Second rate) , 5.72% (Third rate) respectively, and the condition of group B were 31.70%, 26.84%, 41.46%. The treatment effectiveness of group A was better than that of group B. Postoperative complications were less than group B (P < 0.05) . Conclusion Compared with the loss of nerve transplantation of anterolateral thigh perforator flap, sensory nerve anastomosed perforator based anterolateral thigh flap is of great value to reconstruct the defect after resection of tumor in head and neck region and restore the sensation of flap. Key words: Head and neck region; Reconstruction; Anterolateral thigh perforator flap; Sensation reconstruction

A Haptic Feedback System for Phase-Based Sensory Restoration in Above-Knee Prosthetic Leg Users.

Persons with amputations lack important senses from the amputated limb. With the absence of proprioception in the amputated leg, amputees have far more difficulty maintaining a natural gait with balance and stability. The biggest determinant of temporal limb behavior during locomotion is the phase in the gait cycle, which can be estimated using the center of pressure (COP) under the feet. We hypothesize that feedback from the COP of the prosthetic foot can help restore a more robust sense of phase in transfemoral (above-knee) amputees. This paper presents a device that provides vibrotactile feedback based on the COP from the prosthesis, providing proprioception and potentially an improved sense of phase to the user. Experiments showed that the haptic device significantly decreased variability of stride length, step width, and trunk sway in novice (able-bodied) users of a transfemoral prosthetic leg during treadmill locomotion (N=9), indicating improved gait stability.

Cross-Modal Plasticity in Higher-Order Auditory Cortex of Congenitally Deaf Cats Does Not Limit Auditory Responsiveness to Cochlear Implants.

Congenital sensory deprivation can lead to reorganization of the deprived cortical regions by another sensory system. Such cross-modal reorganization may either compete with or complement the "original" inputs to the deprived area after sensory restoration and can thus be either adverse or beneficial for sensory restoration. In congenital deafness, a previous inactivation study documented that supranormal visual behavior was mediated by higher-order auditory fields in congenitally deaf cats (CDCs). However, both the auditory responsiveness of "deaf" higher-order fields and interactions between the reorganized and the original sensory input remain unknown. Here, we studied a higher-order auditory field responsible for the supranormal visual function in CDCs, the auditory dorsal zone (DZ). Hearing cats and visual cortical areas served as a control. Using mapping with microelectrode arrays, we demonstrate spatially scattered visual (cross-modal) responsiveness in the DZ, but show that this did not interfere substantially with robust auditory responsiveness elicited through cochlear implants. Visually responsive and auditory-responsive neurons in the deaf auditory cortex formed two distinct populations that did not show bimodal interactions. Therefore, cross-modal plasticity in the deaf higher-order auditory cortex had limited effects on auditory inputs. The moderate number of scattered cross-modally responsive neurons could be the consequence of exuberant connections formed during development that were not pruned postnatally in deaf cats. Although juvenile brain circuits are modified extensively by experience, the main driving input to the cross-modally (visually) reorganized higher-order auditory cortex remained auditory in congenital deafness. In a common view, the "unused" auditory cortex of deaf individuals is reorganized to a compensatory sensory function during development. According to this view, cross-modal plasticity takes over the unused cortex and reassigns it to the remaining senses. Therefore, cross-modal plasticity might conflict with restoration of auditory function with cochlear implants. It is unclear whether the cross-modally reorganized auditory areas lose auditory responsiveness. We show that the presence of cross-modal plasticity in a higher-order auditory area does not reduce auditory responsiveness of that area. Visual reorganization was moderate, spatially scattered and there were no interactions between cross-modally reorganized visual and auditory inputs. These results indicate that cross-modal reorganization is less detrimental for neurosensory restoration than previously thought.

A modified digital nerve repair technique in replantation of rotational avulsed fingers

Objective To modify the conventional technique for repairing digital nerve in replantation of avulsed fingers, and to evaluate its clinical outcomes. Methods From August 2011 to June 2015, 12 cases of avulsed fingers were replanted. The avulsed digital nerve on one side was harvested as a graft for repair of the digital nerve on the other side. The distal donor digital nerve was then sutured to digital nerve of the recipient side in an end-to-side fashion. Results All 12 replanted fingers survived uneventfully with primary wound healing.All the patients were follow-up for 12 to 18 months. Perfusion, appearance and function of the replanted fingers were good. Pain sensation and temperature sensation returned. Two-point discrimination was 4 to 9 mm on the graft repair side of finger pulp, equivalent to S3+ to S4. Sensory recovery on the end-to-side neurorrhaphy side was S3 to S3+. According to the criteria for functional assessment of replanted fingers issued by the Hand Surgery Society of Chinese Medicine Association, the results were excellent in 7 cases and good in 5 cases. Conclusion In replantation of avulsed fingers, sensory restoration of the pulp can be achieved by using a segment of the digital nerve from one side to graft repair digital nerve of the other side while suturing the distal donor digital nerve to the graft repair digital nerve in an end-to-side fashion. Key words: Fringer injuries; Replantation; Nerve grafting

Intraneural stimulation elicits discrimination of textural features by artificial fingertip in intact and amputee humans.

Restoration of touch after hand amputation is a desirable feature of ideal prostheses. Here, we show that texture discrimination can be artificially provided in human subjects by implementing a neuromorphic real-time mechano-neuro-transduction (MNT), which emulates to some extent the firing dynamics of SA1 cutaneous afferents. The MNT process was used to modulate the temporal pattern of electrical spikes delivered to the human median nerve via percutaneous microstimulation in four intact subjects and via implanted intrafascicular stimulation in one transradial amputee. Both approaches allowed the subjects to reliably discriminate spatial coarseness of surfaces as confirmed also by a hybrid neural model of the median nerve. Moreover, MNT-evoked EEG activity showed physiologically plausible responses that were superimposable in time and topography to the ones elicited by a natural mechanical tactile stimulation. These findings can open up novel opportunities for sensory restoration in the next generation of neuro-prosthetic hands.

Surgical Optimization of Motor Recovery in Face Transplantation.

Face transplantation (FT) has emerged as a viable option for treating devastating facial injuries. Most reported outcomes have demonstrated satisfactory motor and sensory restoration despite differences in technique. The authors have developed an algorithm of facial nerve management in these challenging patients. Our principles of management are illustrated by 2 specific patients. A retrospective analysis of prospectively collected data on 2 full face transplants was performed. Both patients required nerve grafting during full FT. Patient 1 due to short donor facial nerve stumps and patient 2 due to intraoperative soft tissue swelling. Patient 2 required a nerve transfer 11 months after full FT due to impaired motor recovery opposite the side of nerve grafting. Follow-up examinations consisting of manual muscle testing and Sunnybrook Facial Grading System 6 to 42 months after full FT with selected video examinations were critically reviewed. Patient 1 had symmetrical motor recovery with gradual improvements noted throughout. At 6 months, Patient 2 had asymmetrically improving motor function. After nerve transfer, the patient showed gradual improvement in motor recovery, symmetry, and tone. Videos for each patient demonstrate the evolution of the patients' ability to smile from 6 to 42 months. The authors describe their assessment of motor recovery and management of facial nerve reconstruction as it pertains to FT. Finally, the authors illustrate the principles of nerve transfer are applicable to FT recipients.

Mechanical and Biological Interactions of Implants with the Brain and Their Impact on Implant Design.

Neural prostheses have already a long history and yet the cochlear implant remains the only success story about a longterm sensory function restoration. On the other hand, neural implants for deep brain stimulation are gaining acceptance for variety of disorders including Parkinsons disease and obsessive-compulsive disorder. It is anticipated that the progress in the field has been hampered by a combination of technological and biological factors, such as the limited understanding of the longterm behavior of implants, unreliability of devices, biocompatibility of the implants among others. While the field's understanding of the cell biology of interactions at the biotic-abiotic interface has improved, relatively little attention has been paid on the mechanical factors (stress, strain), and hence on the geometry that can modulate it. This focused review summarizes the recent progress in the understanding of the mechanisms of mechanical interaction between the implants and the brain. The review gives an overview of the factors by which the implants interact acutely and chronically with the tissue: blood-brain barrier (BBB) breach, vascular damage, micromotions, diffusion etc. We propose some design constraints to be considered in future studies. Aspects of the chronic cell-implant interaction will be discussed in view of the chronic local inflammation and the ways of modulating it.

Transfer of the radial branch of the superficial radial nerve to the sensory branch of the ulnar nerve for sensory restoration after C7-T1 brachial plexus injury

Previously, we have reconstructed the motor function of patients with C7-T1 brachial plexus palsies through combined nerve and tendon transfers. However, these patients lose not only the motor function of the hand but also the sensation on the ulnar side of the hand. Without sensory recovery, the injured hand may be further damaged, particularly by burns in this contact zone. Therefore, we described a technique to restore the sensation at the ulnar aspect of the hand by performing a transfer of the radial branch of the superficial radial nerve to the sensory branch of the ulnar nerve.

Restoration of Sensibility Following Intentional Infra-Orbital Nerve Transection in Unilateral Cleft Lip Repair

INTRODUCTION: Repair of the wide cleft lip in which presurgical orthopedics is not used can present challenges to achieving a tension-free reconstruction. In order to limit tension during wide cleft lip repair, we routinely sacrifice the infraorbital nerve during mobilization of the lateral lip elements. Prior studies in pediatric hand trauma demonstrate return of sensibility in the absence of nerve repair through the phenomenon of adjacent neurotization. Faivre et al demonstrated good return of light touch sensation in all patients with Semmes-Weinstein monofilaments in the 2.83 to 3.83 range.1 All patients in that study demonstrated return of discriminatory sensation and excellent functional results. The aim of this study is to evaluate the medium-term sensibility outcomes after infraorbital nerve transection during radical cheek dissection at the time of wide cleft lip repairs. MATERIALS AND METHODS: A 3-year single-surgeon retrospective review of patients undergoing unilateral cleft lip repair with radical cheek dissection was performed. Radical cheek dissection was defined as supraperiosteal dissection across the entire face of the maxilla as far superior as the infraorbital rim, transecting the infraorbital nerve. Recorded variables include age at the time of sensory exam, other diagnoses, and results of Semmes-Weinstein monofilament testing (4.31, 3.61, and 2.83 levels) on the side of surgery and the unoperated side.2 RESULTS: Fifty-seven patients underwent unilateral cleft lip repair during the study period and 9 patients met inclusion criteria (Table 1). The mean age at the time of sensory examination was 4.9 years (range 3.9 to 6.2 years). Nine patients had intact lip sensibility on the operated side when stimulated with the finest Semmes-Weinstein monofilament (2.83). None of the patients examined reported a subjective change in sensation across the upper lip. All patients reported an elicited sensory response on the operated side when stimulated with all tested filament levels. There were no patients that had a difference in sensibility compared to the control side (p = 1.00).Table 1: Patient Summary.CONCLUSIONS: Transection of the infraorbital nerve during primary cleft lip repair has no detrimental effect on upper lip sensibility. There should be limited concern for sacrifice of upper lip sensibility during lateral lip mobilization. Prospective, randomized analysis would be required to compare the potential benefit to outcomes that the described technique may offer.