Severe vascular complications after derotational osteotomy of the tibia salvaged with free functional latissimus dorsi muscle transfer. A case report.

We present a case study of a 26-year-old male who sustained severe vascular and neurogenic injury during derotational osteotomy of the tibia. Directly postoperatively he complained of a drop foot, but 3 days later presented with an ischemic compartment syndrome of the anterior and lateral compartments. After debridement the osteotomy and metalware were exposed and the patient had a drop foot. Here we report how we salvaged his lower limb with a free functional latissimus dorsi muscle transfer that reconstructed soft tissues and restored ankle dorsiflexion.

Advances in Microsurgical Treatment Options to Optimize Autologous Free Flap Breast Reconstruction.

Introduction: Reconstructive plastic surgeons have made great strides in the field of breast reconstruction to achieve the best results for patients undergoing treatment for breast cancer. As microsurgical techniques have evolved, these patients can benefit from additional treatment modalities to optimize the results of the reconstruction. Free tissue transfer from alternative donor sites for breast reconstruction is routinely performed, which was not possible in the past. Neurotization is now possible to address the numbness and lack of sensation to the reconstructed breast. For those patients who develop lymphedema of the upper extremity as a result of their breast cancer care, supermicrosurgical options are now available to treat and even to prevent the development of lymphedema. This study presents a narrative review regarding the latest microsurgical advancements in autologous free flap breast reconstruction. Methods: A literature review was performed on PubMed with the key words "autologous free flap breast reconstruction", "deep inferior epigastric perforator flap", "transverse upper gracilis flap", "profunda artery perforator flap", "superior gluteal artery perforator flap", "inferior gluteal artery perforator flap", "lumbar artery perforator flap", "breast neurotization", "lymphovenous bypass and anastomosis", and "vascularized lymph node transfer". Articles that specifically focused on free flap breast reconstruction, breast neurotization, and lymphedema surgery in the setting of breast cancer were evaluated and included in this literature review. Results: The literature search yielded a total of 4948 articles which were screened. After the initial screening, 413 articles were reviewed to assess the relevance and applicability to the current study. Conclusions: Breast reconstruction has evolved tremendously in recent years to provide the most natural and cosmetically pleasing results for those patients undergoing treatment for breast cancer. As technology and surgical techniques have progressed, breast cancer patients now have many more options, particularly if they are interested in autologous reconstruction. These advancements also provide the possibility of restoring sensibility to the reconstructed breast as well as treating the sequela of lymphedema due to their cancer treatment.

Sensory restoration following breast reconstruction with operative reinnervation: A systematic review and meta-analysis.

BACKGROUND: There is currently no consensus on the efficacy of operative reinnervation at the time of post-mastectomy reconstruction. This review compares postoperative sensation between innervated and non-innervated flaps in breast reconstruction through systematic review and meta-analysis. METHODS: EMBASE, Ovid, and CENTRAL were searched from inception to December 6, 2023. The primary outcome was level of sensation postoperatively. Secondary outcomes included presence of sensation, breast-related complications, operative time, and quality of life. Meta-analysis was conducted using mean difference (MD) or standardized mean difference (SMD) for continuous outcomes and odds radio (OR) for dichotomous outcomes. Quality of evidence was appraised using RoB-2/ROBINS-I. Certainty of evidence was assessed with Grading of Recommendations, Assessment, Development and Evaluations. RESULTS: Twenty-eight studies were included; studies were observational studies except one randomized controlled trial. Common flaps were deep inferior epigastric perforator (11/28, 39.3%) and transversus rectus abdominis muscle (9/28, 32.1%). Innervated flaps were significantly associated with improved level of postoperative sensation (SMD: -0.94, 95% CI: [-1.35; -0.53], I2: 78%, p < 0.01), presence of postoperative sensation (OR: 11.4, 95% CI: [5.09; 24.5], I2: 0%, p < 0.01), and improved postoperative BREAST-Q scores (MD: 8.11, 95% CI: [4.33; 11.89], I2: 27%, p < 0.01). However, certainty of evidence was low/very low for all outcomes. Most studies had moderate risk of bias (56.5%). There were no statistically significant differences in breast-related complications or operative time. CONCLUSIONS: Operative reinnervation in breast reconstruction is significantly associated with improved level and presence of postoperative sensation and BREAST-Q scores without significant increase in breast-related complications/operative time. More high-quality studies are required to improve the certainty of outcomes.

Long-Term Evaluation of Patients with Neurotrophic Keratopathy Undergoing Staged Keratoplasty After Corneal Neurotization.

PURPOSE: Corneal neurotization (CN) is a novel, potentially curative surgical procedure for the treatment of neurothophic keratopathy (NK). Patients with severe NK can present with corneal opacification requiring optical keratoplasty, which would likely fail without a proper trophic support of corneal nerves in the recipient cornea. METHODS: This is a pilot study on 4 patients undergoing keratoplasty after CN. Pre- and postoperative data at 12, 24 months and at the last follow-up were collected for the examination of (i) best corrected visual acuity (BCVA), (ii) slit lamp examination and photograph acquisition with and without fluorescein staining, (iii) corneal aesthesiometry, (iv) in vivo confocal microscopy of the central cornea. Neurophysiological study of the corneal reflex before corneal graft and at last follow up was performed. RESULTS: Four female patients (47.25 ± 5.06 y.o.) underwent keratoplasty after CN (3 penetrating keratoplasty, 1 deep anterior lamellar keratoplasty). The mean interval between CN and keratoplasty was 22 (± 12) months. The mean graft survival time was 42 (± 25) months. Graft follow-up ranged from 72 to 132 months. At the final follow-up, BCVA was improved in 2 out of 4 patients. The mean corneal sensitivity was 11.9 ± 8.3 mm at last follow-up. In vivo confocal microscopy confirmed the presence of functioning nerves at the last follow-up in all patients. NK-related complications occurred in 3 eyes (2 persistent epithelial defect, 1 corneal melting). The former complication was successfully treated by autologous serum eye drops while the latter required repeated keratoplasty. CONCLUSIONS: Keratoplasty is a viable strategy to improve visual acuity in patients with corneal opacity who underwent CN for the treatment of NK. Even in the presence of functioning corneal nerves before keratoplasty, surgeons should be aware of the increased rate of NK-related complications that could require the need for repeated procedure.

Direct muscle neurotization: Previous advancements in animal models.

Peripheral nerve repair is daily activity for several microsurgeons. Numerous nerve repair techniques are applied, including neurorrhaphy, nerve grafting and nerve transfer, depending on the nature and extent of the injury. However, these techniques become unfeasible when the distal nerve end is not preserved during the peripheral nerve injury or a segment of the muscle is transferred without the nerve supplying it. However, direct muscle neurotization (DMN) achieves muscle reinnervation by suturing the nerve directly into the muscle tissue, without requiring a distal nerve end for coaptation. Despite promising results in the literature, DMN is not widely adopted in clinical practice. Animal models may help in advancing novel therapeutic approaches, due to their anatomic and physiologic similarities to humans. This review highlights the current scientific understanding and recent advancements in DMN as well as the animal models and target muscle that have been used in the past to investigate the basic principles behind this surgical technique. The presented information should aid in establishing the clinical importance of DMN in peripheral nerve injury.

Feasibility of a less invasive supercharged end-to-side anterior interosseous nerve to ulnar motor nerve transfer.

The object of this study was to perform an anatomical dissection of Thiel-embalmed specimens in a step-by-step procedure, to establish a 'safe zone' in which to perform a less invasive supercharged end-to-side (SETS) anterior interosseous nerve to ulnar motor nerve transfer without tension and to demonstrate its feasibility. The sample size was calculated with a 5 mm error to reach a 95% confidence interval. Dissection was performed in 15 specimens and the 'safe zone' was established between 40 and 90 mm proximal to the pisiform. Several surgical tips are recommended to help complete the procedure. A reproducible 'safe zone' was found for performing a SETS anterior interosseous to ulnar motor nerve transfer with 95% certainty, reducing soft tissue damage and enhancing the original surgical technique.

The effect of increasing motor end-plate innervation on smile activation in acute and early facial palsy.

While it has been over half a century since primary cross-facial nerve grafting was first described for facial reanimation, the outcome of this procedure, remains inconsistent and provide lesser smile excursion when compared to the likes of the masseteric nerve. However, the latter itself has limitations in terms of the lack of spontaneity and resting tone. While combinations have been attempted more proximally, we ask the question as to whether more distal nerve transfers with vascularized nerve grafts are a better option. In a retrospective review of clinical practice at our institute, 16 consecutive patients had single, double, and finally triple distal nerve transfers, close to the target facial muscle to reinnervate the motor endplates directly, over a 6-year period (2018-23). All patients had the onset of facial palsy within 18 months. Statistical analysis of the comparison between three sub-cohorts was performed using student's t-test and one-way ANOVA, respectively. Qualitatively, masseteric neurotization of a single facial nerve branch translated into smile improvement in 50% of cases, as opposed to all cases of double- and triple-neurotization of the smile muscles. In terms of upper lip elevation, single neurotization showed improvement in 25% of cases, double-neurotization in 40% of cases and triple-neurotization in 100% of cases. Upper lip elevation was also significantly better in those who had a vascularized cross-facial nerve graft (Student's t-test <0.05). In summary, increasing neural input to the motor endplates of smile muscles can significantly improve smile activation, in acute flaccid facial palsies.

Restoring Sensation through Abdominal Flap Neurotization in Breast Reconstruction.

Breast sensation plays a significant role in the safety and quality of life of women who undergo mastectomy and reconstruction. In 1992, Slezak et al. introduced the concept of abdominal flap neurotization to improve sensation of the reconstructed breast. Over the next 30 years, numerous studies iterated on Slezak's technique, suggesting technical modifications and new methodologies for assessing sensory recovery. Despite evidence that reinnervation increases patient satisfaction following autologous breast reconstruction, abdominal flap neurotization remains a rarely performed procedure. In this article, we review the evolution of flap neurotization in breast reconstruction and describe our approach to facilitating sensory recovery of the breast while limiting donor site morbidity.

Insights on the Choice and Preparation of the Donor Nerve in Corneal Neurotization for Neurotrophic Keratopathy: A Narrative Review.

The article introduces neurotrophic keratopathy (NK), a condition resulting from corneal denervation due to various causes of trigeminal nerve dysfunctions. Surgical techniques for corneal neurotization (CN) have evolved, aiming to restore corneal sensitivity. Initially proposed in 1972, modern approaches offer less invasive options. CN can be performed through a direct approach (DCN) directly suturing a sensitive nerve to the affected cornea or indirectly (ICN) through a nerve auto/allograft. Surgical success relies on meticulous donor nerve selection and preparation, often involving multidisciplinary teams. A PubMed research and review of the relevant literature was conducted regarding the surgical approach, emphasizing surgical techniques and the choice of the donor nerve. The latter considers factors like sensory integrity and proximity to the cornea. The most used are the contralateral or ipsilateral supratrochlear (STN), and the supraorbital (SON) and great auricular (GAN) nerves. Regarding the choice of grafts, the most used in the literature are the sural (SN), the lateral antebrachial cutaneous nerve (LABCN), and the GAN nerves. Another promising option is represented by allografts (acellularized nerves from cadavers). The significance of sensory recovery and factors influencing surgical outcomes, including nerve caliber matching and axonal regeneration, are discussed. Future directions emphasize less invasive techniques and the potential of acellular nerve allografts. In conclusion, CN represents a promising avenue in the treatment of NK, offering tailored approaches based on patient history and surgical expertise, with new emerging techniques warranting further exploration through basic science refinements and clinical trials.

Herpes simplex keratitis: A brief clinical overview.

The aim of our minireview is to provide a brief overview of the diagnosis, clinical aspects, treatment options, management, and current literature available regarding herpes simplex keratitis (HSK). This type of corneal viral infection is caused by the herpes simplex virus (HSV), which can affect several tissues, including the cornea. One significant aspect of HSK is its potential to cause recurrent episodes of inflammation and damage to the cornea. After the initial infection, the HSV can establish a latent infection in the trigeminal ganglion, a nerve cluster near the eye. The virus may remain dormant for extended periods. Periodic reactivation of the virus can occur, leading to recurrent episodes of HSK. Factors triggering reactivation include stress, illness, immunosuppression, or trauma. Recurrent episodes can manifest in different clinical patterns, ranging from mild epithelial involvement to more severe stromal or endothelial disease. The severity and frequency of recurrences vary among individuals. Severe cases of HSK, especially those involving the stroma and leading to scarring, can result in vision impairment or even blindness in extreme cases. The cornea's clarity is crucial for good vision, and scarring can compromise this, potentially leading to visual impairment. The management of HSK involves not only treating acute episodes but also implementing long-term strategies to prevent recurrences and attempt repairs of corneal nerve endings via neurotization. Antiviral medications, such as oral Acyclovir or topical Ganciclovir, may be prescribed for prophylaxis. The immune response to the virus can contribute to corneal damage. Inflammation, caused by the body's attempt to control the infection, may inadvertently harm the corneal tissues. Clinicians should be informed about triggers and advised on measures to minimize the risk of reactivation. In summary, the recurrent nature of HSK underscores the importance of both acute and long-term management strategies to preserve corneal health and maintain optimal visual function.

Sensory and pain outcomes of neurotized skin-grafted free gracilis muscle flaps for lower extremity reconstruction.

BACKGROUND: Skin-grafted free gracilis muscle flaps are commonly used for lower extremity reconstruction. However, the loss of sensory function may lead to increased patient morbidity. This study prospectively analyzed the sensory and neuropathic pain outcomes of neurotized skin-grafted free gracilis muscle flaps used for the reconstruction of lower extremity defects. METHODS: Patients undergoing lower extremity reconstructions between 2020 and 2022 with neurotized skin-grafted free gracilis muscle flaps were prospectively enrolled. Sensation was assessed at 3, 6 and 12 months postoperatively using monofilaments, two-point discrimination, a vibration device, and cold and warm metal rods. Sensations were tested in the center and periphery of the flaps, as well as in the surrounding skin. The contralateral side served as the control. Patients completed the McGill pain questionnaire to evaluate patient-reported neuropathic pain. RESULTS: Ten patients were included. At 12 months postoperatively, monofilament values improved by 44.5% compared to that of the control site, two-point discrimination, cold detection, warmth detection, and vibration detection improved by 36.2%, 48%, 50%, and 88.2%, respectively, at the reconstructed site compared to those at the control site. All sensory tests were significantly better than 3 and 6 months values (p < 0.05), but remained significantly poorer than the control site (p < 0.05). Sensation in the central flap areas were similar to peripheral flap areas throughout the follow-up period (p > 0.05). The surrounding skin reached values similar to the control site at 12 months (p > 0.05). Moreover, 50% of patients reported neuropathic pain at 3 months postoperatively, 40% at 6 months, and 0% at 12 months (p < 0.05). CONCLUSION: Mechanical detection, vibration detection, temperature detection, and two-point discrimination significantly improved over time but without reaching normal sensory function at 12 months postoperatively. Neuropathic pain resolved at 12 months.

Neurotrophic keratopathy: General features and new therapies.

Neurotrophic keratopathy is an uncommon degenerative corneal disorder characterized by compromised corneal sensory innervation resulting in the formation of epithelial defects and nonhealing corneal ulcers. Various treatment modalities are available to stabilize disease progression, improve patient well-being, and prevent vision loss. For eligible patients, medical and surgical reinnervation have emerged as pioneering therapies, holding promise for better management. We present a comprehensive review of the disorder, providing an update relevant to ophthalmologists on pathogenesis, diagnosis, treatment options, and novel therapies targeting pathophysiological pathways.

Perineural differentiation in neurotized nevi.

BACKGROUND: Perineuriomatous melanocytic nevi are rare and this may indicate the similar embryological source of melanocytes and peripheral nerves in the neural crest. Neurotized melanocytic nevi may resemble nerve sheath tumors histologically, and show schwannian differentiation. However, literature on whether neurotized nevi differentiate into perineural cells is controversial. We examined our cases of neurotized nevi for evidence of perineural differentiation. MATERIALS AND METHODS: A total of 100 benign nevi with large neurotized component (microscopically involved a low power field 4.2 mm in diameter) were prospectively evaluated in excisional biopsy samples. Immunohistochemical stainings for EMA, Claudin1, Glut1 and neurofilament were performed. RESULTS: Perineural differentiation was immunohistochemically detected in the neurotized component of the nevi in 61% of the cases with EMA and in all the cases with Glut1 and Claudin1. Axonal differentiation was not detected with neurofilament. The expression pattern, especially with Glut1, was usually in form of partial or complete staining surrounding the Meissner's corpuscle-like structure (MCLS). Also, a linear/curvilinear staining pattern was observed particularly with Claudin1. A diffuse staining pattern with EMA, Glut1 and Claudin1 was detected in a case with a microscopically distinct whorl structure, and in which spindle cells are separated from the superficial epithelioid melanocytes with an abrupt transition histologically. These findings of the case are compatible with previous reports of perineuromatous nevus. CONCLUSION: Perineural differentiation is not uncommon and immunohistochemically observed in all nevi with a relatively large component of neurotization. To prevent misdiagnosing desmoplastic melanoma and overtreating patients, it is crucial to be aware of perineuromatous nevi.

[Femoral nerve repair with autografts for proximal retroperitoneal damage (case report and literature review)]. / Autoplastika bedrennogo nerva pri ego proksimal'nom zabryushinnom povrezhdenii (klinicheskoe nablyudenie i obzor literatury).

Femoral nerve damage, especially in proximal retroperitoneal space, is rare. Therefore, surgical strategy is still unclear for these patients. Various specialists discuss repair with autografts or neurotization by the obturator nerve or its muscular branch. OBJECTIVE: To demonstrate the diagnostic algorithm for proximal femoral nerve injury and favorable outcomes after repair with long autografts. MATERIAL AND METHODS: We assessed movements and sensitivity using a five-point scale, as well as ultrasound, magnetic resonance imaging and electroneuromyography data in a patient with extended iatrogenic femoral nerve damage before and after repair with long autografts (10.5 cm). RESULTS AND DISCUSSION: The patient had complete femoral nerve interruption in proximal retroperitoneal space with 10-cm defect that required repair with five autografts from two sural nerves. Postoperative ultrasound and magnetic resonance imaging revealed signs of graft survival and no neuroma within the nerve suture lines. The first signs of motor recovery occurred after 10 months. After 14 months, strength of quadriceps femoris muscle comprised 4 points, and electroneuromyography confirmed re-innervation. CONCLUSION: Femoral nerve repair with autografts for complete proximal anatomical interruption can provide sufficient restoration of movements and sensitivity. Therefore, this surgical option should be preferred instead of neurotization. Ultrasound, MRI and ENMG are valuable to clarify the diagnosis and state of the autografts.

Viral Keratitis, Surgical Intervention in Viral Keratitis, Challenges in Diagnosis and Treatment of Viral Keratitis, HSV, HZV.

Viral keratitis is a significant cause of ocular morbidity and visual impairment worldwide. In recent years, there has been a growing understanding of the pathogenesis, clinical manifestations, and diagnostic modalities for viral keratitis. The most common viral pathogens associated with this condition are adenovirus, herpes simplex (HSV), and varicella-zoster virus (VZV). However, emerging viruses such as cytomegalovirus (CMV), Epstein-Barr virus (EBV), and Vaccinia virus can also cause keratitis. Non-surgical interventions are the mainstay of treatment for viral keratitis. Antiviral agents such as Acyclovir, Ganciclovir, and trifluridine have effectively reduced viral replication and improved clinical outcomes. Additionally, adjunctive measures such as lubrication, corticosteroids, and immunomodulatory agents have alleviated symptoms by reducing inflammation and facilitating tissue repair. Despite these conservative approaches, some cases of viral keratitis may progress to severe forms, leading to corneal scarring, thinning, or perforation. In such instances, surgical intervention becomes necessary to restore corneal integrity and visual function. This review article aims to provide an overview of the current perspectives and surgical interventions in managing viral keratitis. The choice of surgical technique depends on the extent and severity of corneal involvement. As highlighted in this article, on-going research and advancements in surgical interventions hold promise for further improving outcomes in patients with viral keratitis.

Porcine Acellular Nerve-Derived Hydrogel Improves Outcomes of Direct Muscle Neurotization in Rats.

Background: The ability to reinnervate a muscle in the absence of a viable nerve stump is a challenging clinical scenario. Direct muscle neurotization (DMN) is an approach to overcome this obstacle; however, success depends on the formation of new muscle endplates, a process, which is often limited due to lack of appropriate axonal pathfinding cues. Objective: This study explored the use of a porcine nerve extracellular matrix hydrogel as a neuroinductive interface between nerve and muscle in a rat DMN model. The goal of the study was to establish whether such hydrogel can be used to improve neuromuscular function in this model. Materials and Methods: A common peroneal nerve-to-gastrocnemius model of DMN was developed. Animals were survived for 2 or 8 weeks following DMN with or without the addition of the hydrogel at the site of neurotization. Longitudinal postural thrust, terminal electrophysiology, and muscle weight assessments were performed to qualify and quantify neuromuscular function. Histological assessments were made to qualify the host response at the DMN site, and to quantify neuromuscular junctions (NMJs) and muscle fiber diameter. Results: The hydrogel-treated group showed a 132% increase in postural thrust at 8 weeks compared with that of the DMN alone group. This was accompanied by an 80% increase in the number of NMJs at 2 weeks, and 26% increase in mean muscle fiber diameter at 8 weeks. Conclusions: These results suggest that a nerve-derived hydrogel may improve the neuromuscular outcome following DNM.

Surgical reconstructions for adult brachial plexus injuries. Part II: Treatments for total arm type.

Brachial plexus injuries (BPI) contribute not only to physical dysfunction but also to socioeconomic aspects and psychological disability. Patients with total arm-type BPI will lose not only the shoulder and elbow function but also the hand function, making reconstruction particularly challenging. Reconstructive procedures commonly include nerve repair, grafting, neurotization (nerve transfer), tendon transfer and free functional muscle transfer (FFMT). Although it is difficult to achieve prehensile hand function, most of patients with total arm-type BPI can be treated with satisfied outcomes. In addition to surgical techniques, comprehensive rehabilitation is another important factor for successful outcomes, and efficient communication can help to boost patient morale and eliminate uncertainty.

Neurotrophic keratopathy: Clinical presentation and outcomes in 354 eyes in a community-based population.

PURPOSE: To describe the frequency, clinical presentation, and outcomes of neurotrophic keratopathy (NK). METHODS: Retrospective cohort study of Kaiser Permanente Northern California patients diagnosed with NK using ICD-10 code H16.23X from October 1, 2016 through May 31, 2021 was conducted. The electronic medical record was used to obtain demographic information, systemic and ocular comorbidities, corrected distance visual acuity (CDVA), Mackie stage, laterality, etiology, complications, interventions, and medications. The data were analyzed using cross-tabulations. RESULTS: 354 eyes in 322 patients presented with an initial or recurrent episode of NK. 9.9% had bilateral NK, 40% were 75 years and older, and 55% were women. Baseline vision was worse than 20/100 in 47.5%. Mackie staging was stage 1 in 37.3%, stage 2 in 32.5%, and stage 3 in 30.2%. Herpetic causes comprised 34.9%, followed by diabetes (12.4%), ocular surgery (10.4%), and central nervous system etiologies (9.0%). Topical antibiotics (74.5%), steroids (54.0%), autologous serum tears (46.0%), and oral antivirals (43.8%) were the most used treatments. There were 8 eyes with perforation, 4 endophthalmitis, and 3 evisceration/enucleations. An increased difference of approximately 0.1 logMAR in CDVA in the affected eye compared with the unaffected eye over one year was not statistically significant. Clinic utilization for stage 2 (average visits per month, 3.2) and stage 3 (5.0) NK gradually decreased over 6 months. CONCLUSIONS: Summary of the current management, outcomes, and healthcare utilization of NK provides valuable benchmarks in assessing the disease burden in the community and for further development of novel therapies.

How to Enhance the Success of Selective Neurectomy for Facial Synkinesis by Considering the Patient's Preferences: Lesson Learned from a Retrospective Analysis of 122 Cases.

BACKGROUND: Facial synkinesis can result in facial tightness, smile dysfunction, and eyelid aperture narrowing due to overactive and uncoordinated muscle activity. We hypothesized that the outcome of a selective neurectomy could rely on the patient's chief complaints. METHODS: We retrospectively reviewed 122 patients who underwent selective neurectomy at our hospital. Preoperatively, the patients were asked nine questionnaires to identify their two major chief complaints (treatment priorities). Postoperatively, facial tightness, limited mouth movement, and eyelid aperture narrowing were measured. RESULTS: The most common chief complaints in our series were facial tightness (n=38), eyelid narrowing (n=32), and limited mouth movement (n=28); the second most common chief complaints (second priority) were limited mouth movement (n=47), facial tightness (n=21), and eyelid narrowing (n=20). The mean score for facial tightness significantly improved from 4.3 to 1.1 in the first priority group. Among the 28 patients whose corners of the mouth constituted the top priority of surgical correction, the vertical inclination on the affected side significantly improved from 74.1 ± 7.6° to 55.5 ± 6.0°, and the horizontal angles were changed from 4.2 ± 2.7° to 2.0 ± 1.3° after selective neurectomy without statistically significant. Among the 32 patients for whom eyelid narrowing constituted the top priority, the mean eyelid narrowing score improved from 4.5 ± 1.1 to 1.5 ± 1.2. CONCLUSIONS: Selective neurectomy can provide a significantly satisfactory outcome regarding facial tightness and eyelid aperture narrowing. The vertical inclination of the mouth corner can be significantly improved, while the improvement of horizontal angles can be suboptimal. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

The Role of Sensory Innervation in Homeostatic and Injury-Induced Corneal Epithelial Renewal.

The cornea is the window through which we see the world. Corneal clarity is required for vision, and blindness occurs when the cornea becomes opaque. The cornea is covered by unique transparent epithelial cells that serve as an outermost cellular barrier bordering between the cornea and the external environment. Corneal sensory nerves protect the cornea from injury by triggering tearing and blink reflexes, and are also thought to regulate corneal epithelial renewal via unknown mechanism(s). When protective corneal sensory innervation is absent due to infection, trauma, intracranial tumors, surgery, or congenital causes, permanent blindness results from repetitive epithelial microtraumas and failure to heal. The condition is termed neurotrophic keratopathy (NK), with an incidence of 5:10,000 people worldwide. In this report, we review the currently available therapeutic solutions for NK and discuss the progress in our understanding of how the sensory nerves induce corneal epithelial renewal.