Direct Midline Research Articles

Revisiting anterior longitudinal ligament release: Are we ready for an endoscopic approach?

Anterior longitudinal ligament release is a proven method for restoring spinopelvic parameters. This technique is mostly described using either lateral or anterior approaches with paucity regarding a posterior method. This paper is the first to provide descriptive analysis of the neurovascular anatomy in the context of planning for a posterior endoscopic ALL release. A retrospective chart review was performed on patients underwent any lumbar surgery by a single surgeon. Anatomical data was obtained from pre-operative CT to describe the location of key neurovascular structures in relation to the ALL with focus on posterior approach. A total of 20 patients were included in data analysis. A posterior approach with endoscopic assistance would be feasible at L4/5 and L5/S1, where the bifurcation of the abdominal aorta has occurred with a vessel window that ranges from 18.85 mm to 33.45 mm with at least 2 mm space between the vessels and the corresponding disc spaces in the anterior-posterior dimension with slight predilection of the left side at the L5/S1 level to avoid any neurovascular structures. Our study confirmed the findings of previous studies examining the vascular anatomy associated with the lumbar spine. Interestingly, we found that direct midline would likely not be the best location for a posterior annulotomy, and that both the window between the iliac vessels as well as the distance in AP dimension between the spine and vessels increases as you descend the lumbar spine. This information will help guide future efforts to fully develop a safe and reproducible posterior endoscopic ALL release.

Endoscopic resection of enthesopathy via a direct midline transtendinous approach with associated reattachment of the Achilles tendon (endo-REDMTART): a cadaveric feasibility study.

The aim of our study was to determine the feasibility of an all-posterior endoscopic resection of enthesopathy via direct midline transtendinous approach with detachment and reattachment of the Achilles tendon (endo-REDMTART). Endo-REDMTART was performed in 10 ankles by two foot and ankle surgeons. Posterolateral and posteromedial portals were utilized. Three accessory, more distal portals were utilized (one posterolateral, one posteromedial, and one midline transtendinous). We measured the quality of the resection of the calcaneal spur and the length of tendon that was able to be reattached to the calcaneus. The procedure was successful in all 10 cases. The mean minimum thickness of resected calcaneal spur was 7mm (5-9mm) thick, and the mean anteroposterior distance was 23mm (20-25mm). In all 10 cases, the maximum distance between the distal Achilles tendon and calcaneus was 1mm (0-1mm), with good tendon-bone contact. The data here suggest that endo-REDMTART is feasible. This procedure provides all of the advantages of endoscopic technique without compromising the efficacy of Haglund deformity resection. No Clinical Trials Registration or IRB is required. Anatomy study; cadaveric dissection.

Combined strategy of maximal endoscopic endonasal resection and early radiation therapy for complex cystic and solid craniopharyngioma: operative video.

Craniopharyngioma is a rare and benign intracranial tumor of the sellar and suprasellar region. Historically, these tumors were mostly accessed through transcranial corridors and resected with microsurgical techniques. Endoscopic endonasal surgery has recently gained popularity in the treatment of these tumors and has shown at least comparable results to transcranial approaches. The endoscopic endonasal approach provides direct midline access through a transplanum transtuberculum corridor and gives excellent visualization of the undersurface of the optic chiasm to allow safe bimanual sharp dissection of the tumor from the hypothalamus. In this operative video, we demonstrate the case of a 56-year-old female who had a complex craniopharyngioma with solid and cystic components extending superolaterally into the right frontal lobe. This lesion was invasive and partially encased the right optic nerve, optic chiasm, and anterior communicating artery complex. Although a traditional transcranial approach could have been utilized, we elected for an endoscopic endonasal approach for a maximal safe near-total resection, preserving the neurovascular structures. The patient underwent radiation therapy with favorable regression of the residual tumor on subsequent imaging studies. This case illustrates the feasibility of a combined strategy of maximal safe endoscopic endonasal resection followed by early radiation therapy for a complex, invasive cystic and solid craniopharyngioma. The technical nuances of safe bimanual microsurgical dissection of tumor adhesions off of critical neurovascular structures are demonstrated.The video can be found here: https://youtu.be/z0AINLpRZGs.

Prepless Direct Midline Diastema Closure in a Single Visit: 18 months Follow-up Report

Maxillary midline (major) diastemas are common aesthetic problems for the patients. Recently, it is easier to get rid of those unwilling spaces aesthetically with the help of newly developed restorative materials. Major diastema may frequently occur due to high frenulum junctions thus causing unaesthetic outlook for some patients. In this case report a maxillary major diastema due to high frenulum was closed non-invasively with direct, prepless composite resin restorations. In this case frenectomy, office bleaching and direct prepless restorations was respectively planned. Six weeks were waited for periodontal tissue healing after frenectomy operation and then bleaching procedure was done using 40% hydrogen peroxide gel ( Opalescence Xtra Boost, Ultradent, USA ). Following vital bleaching; after 2 weeks, universal adhesive agent (Universal bond, Kuraray Noritake, Japan) was applied to the etched enamel surfaces (36% phosphoric acid etching with DeTrey Conditioner 36, Dentsply, Germany). Direct composite resin restorations was done using “A1B” and “NE” shades ( Estelite Asteria, Tokuyama Dental, Japan ). Polishing discs (SofLex, 3M ESPE, USA), interdental strips (Epitex, GC, Japan) and two spiral polishing twists (Twist Dia, Kuraray, Japan) was used during the finishing and polishing stages. The success of the final restorations were assessed in 3 month, 9 month and 18 month follow ups.

A Modified Direct Posterior Midline Approach for the Treatment of Posterior Column Tibial Plateau Fractures.

The purpose of this study was to introduce a modified surgical approach for the treatment of posterior column tibial plateau fractures. Fifteen patients with posterior column fractures with or without other column fractures were included and treated with this approach between July 2015 and June 2016. The patients were followed up for 18 to 24 months (20.9 ± 1.8 months). Outcomes included neural or vascular injuries, wound complications, nonunion, plate loosening or breakage, and Hospital for Special Surgery (HSS) scores. Bone union was observed in all cases, and the average time for bone union was 13.5 ± 1.4 weeks (11-16 weeks). No neurovascular injuries, malunion, nonunions, or plate loosening or breakages were observed. The average HSS score was 94.7 ± 4.1 (range: 84-100). The modified direct posterior midline approach can provide excellent exposure and facilitate reduction and internal fixation of posterior column fractures of the tibial plateau, including split and depressed fractures. We expect that this approach can be used as a new effective method for managing complex posterior tibial fractures.

Brain Stem Cavernous Malformations: Operative Nuances of a Less-Invasive Resection Technique.

Different operative techniques are reported for the resection of brainstem cavernous malformations (BSCMs). The senior author has previously reported on a less-invasive technique of entering the brain stem with piecemeal removal of BSCMs, especially the deep-seated ones. To present a larger series of these lesions, emphasizing the approach to the brain stem via case selection. We discuss the nuances of the less-invasive operative technique through case illustrations and intraoperative videos. A retrospective review of 46 consecutive cases of BSCMs, with their clinical and radiographic data, was performed. Nine cases were selected to illustrate 7 different operative approaches, and discuss surgical nuances of the less-invasive technique unique to each. Postoperative morbidity, defined as an increase in modified Rankin Scale, was observed in 5 patients (10.9%). A residual BSCM was present in 2 patients (4.3%); both underwent reoperation to remove the remainder. At follow-up of 31.1 ± 27.8 mo, 3 patients experienced recurrence (6.5%). Overall, 65% of our patients improved, 20% stayed the same, and 11% worsened postsurgery. Two patients died, yielding a mortality of 4.3%. Using the less-invasive resection technique for piecemeal BSCM removal, in appropriately selected patients, has yielded comparable to improved patient outcomes over existing large series. In our experience, lateral, anterolateral, and posterolateral approaches are favorable over direct midline (dorsal or ventral) approaches. A thorough understanding of brain-stem safe-entry zones, in conjunction with appropriate approach selection, is key to a good outcome in challenging cases.

Brain Stem Cavernous Malformations: Operative Nuances of a Less Invasive Resection Technique

Background Different operative techniques are reported for the resection of brainstem cavernous malformations (BSCMs). The senior author has previously reported on a less-invasive technique of entering the brain stem with piecemeal removal of BSCMs, especially the deep-seated ones. Objective To present a larger series of these lesions, emphasizing the approach to the brain stem via case selection. We discuss the nuances of the less-invasive operative technique through case illustrations and intraoperative videos. Methods A retrospective review of 46 consecutive cases of BSCMs, with their clinical and radiographic data, was performed. Nine cases were selected to illustrate 7 different operative approaches, and discuss surgical nuances of the less-invasive technique unique to each. Results Postoperative morbidity, defined as an increase in modified Rankin Scale, was observed in 5 patients (10.9%). A residual BSCM was present in 2 patients (4.3%); both underwent reoperation to remove the remainder. At follow-up of 31.1 ± 27.8 mo, 3 patients experienced recurrence (6.5%). Overall, 65% of our patients improved, 20% stayed the same, and 11% worsened postsurgery. Two patients died, yielding a mortality of 4.3%. Conclusion Using the less-invasive resection technique for piecemeal BSCM removal, in appropriately selected patients, has yielded comparable to improved patient outcomes over existing large series. In our experience, lateral, anterolateral, and posterolateral approaches are favorable over direct midline (dorsal or ventral) approaches. A thorough understanding of brain-stem safe-entry zones, in conjunction with appropriate approach selection, is key to a good outcome in challenging cases.

Optimal Initial Trocar Placement for Morbidly Obese Patients.

Background and Objectives:Rates of morbid obesity are skyrocketing worldwide. Not only bariatric surgeons, but also general surgeons are often operating on morbidly obese patients. Many general surgeons still use the same anatomic landmarks for patients with body mass index (BMI) over 35 mg/kg2 as they do for patients of normal weight and can therefore find accessing the morbidly obese abdominal organs difficult. This paper will describe a technique that is easily reproducible and applicable in a wide range of laparoscopic cases.Method:The xiphoid process is the only landmark referenced. From the xiphoid process, the surgeon puts 2 fists together and places the first trocar inferiorly 2 cm lateral to the midline in either direction. The umbilicus is not used as a landmark. This placement is 15–18 cm inferior to the xiphoid process, but allows adequate visualization for any foregut case. An optical trocar is used.Results:In over 1400 bariatric cases, the initial trocar was safely placed with this technique. Most of these cases were performed with the method, but some had one modification: the first trocar was placed in the midclavicular line in the subcostal area if there were previous midline scars. In no cases was an extra-long, or bariatric, trocar used.Conclusions:Laparoscopic access in morbidly obese patients does not have to be difficult. Using an optical trocar off the midline 15–18 cm below the xiphoid process will provide reliable, safe access in the morbidly obese patient, with excellent visualization of the target anatomy.

Post-acute delivery of memantine promotes post-ischemic neurological recovery, peri-infarct tissue remodeling, and contralesional brain plasticity

The NMDA antagonist memantine preferentially inhibits extrasynaptic NMDA receptors, which are overactivated upon stroke and thought to disturb neuroplasticity. We hypothesized that memantine enhances post-ischemic neurological recovery, brain remodeling, and plasticity. C57BL6/j mice were exposed to intraluminal middle cerebral artery occlusion. Starting 72 hours post-stroke, vehicle or memantine (4 or 20 mg/kg/day) were subcutaneously delivered over 28 days. Neurological recovery, perilesional tissue remodeling and contralesional pyramidal tract plasticity were evaluated over 49 days. Memantine, delivered at 20 but not 4 mg/kg/day, persistently improved motor-coordination and spatial memory. Secondary striatal atrophy was reduced by memantine. This delayed neuroprotection was associated with reduced astrogliosis and increased capillary formation around the infarct rim. Concentrations of BDNF, GDNF, and VEGF were bilaterally elevated by memantine in striatum and cortex. Anterograde tract tracing studies revealed that memantine increased contralesional corticorubral sprouting across the midline in direction to the ipsilesional red nucleus. In the contralesional motor cortex, the NMDA receptor subunit GluN2B, which is predominantly expressed in extrasynaptic NMDA receptors, was transiently reduced by memantine after 14 days, whereas GluN2A and PSD-95, which preferentially co-localize with synaptic NMDA receptors, were increased after 28 days. Our data suggest the utility of memantine for enhancing post-acute stroke recovery.

Direct Midline Diastema Closure with Composite Layering Technique: A One-Year Follow-Up.

Objective. Maxillary anterior spacing is a common aesthetic complaint of patients. Midline diastema has a multifactorial etiology such as labial frenulum, microdontia, mesiodens, peg-shaped lateral incisors, agenesis, cysts, habits such as finger sucking, tongue thrusting, or lip sucking, dental malformations, genetics, proclinations, dental-skeletal discrepancies, and imperfect coalescence of interdental septum. Appropriate technique and material for effective treatment are based on time, physical, psychological, and economical limitations. Direct composite resins in diastema cases allow dentist and patient complete control of these limitations and formation of natural smile. Clinical Considerations. In this case report a maxillary midline diastema was closed with direct composite resin restorations in one appointment without any preparation. One bottle total etch adhesive was used and translucent/opaque composite resin shades were layered on mesial surfaces of the teeth that were isolated with rubber dam and Teflon bands. Finishing and polishing procedures were achieved by using polishing discs. Patient was informed for recalls for every 6 months. Conclusions. At one-year recall no sensitivities, discolorations, or fractures were detected on teeth and restorations. Direct composite resins seemed to be highly aesthetic and durable restorations that can satisfy patients as under the conditions of case presented.

Endoscopic endonasal transplanum transtuberculum approach for retrochiasmatic craniopharyngiomas: Operative nuances.

The surgical treatment of craniopharyngiomas is challenging. An optimal surgical approach is extremely important to achieve complete removal of the tumor, which is often the goal of treatment. Conventionally, the endoscopic transsphenoidal approach is used for resection of craniopharyngiomas that are essentially confined to the sellar cavity, or have smaller suprasellar extension. However, the tumors located in the retrochiasmatic space are difficult to remove surgically due to a poor access. Traditionally, various transcranial microsurgical routes have been employed with limited success for resection of retrochiasmatic craniopharyngiomas. The transcranial approaches generally do not provide adequate exposure of the tumors originating in the space under the optic chiasm and nerves. Recently, the extended endonasal endoscopic surgical route, obtained by removal of the tuberculum sellae and planum sphenoidale, has been used with great success in the surgical management of tumors lying ventral to the optic chiasm, including craniopharyngiomas. It offers a direct midline access to the retrochiasmatic space and provides excellent visualization of the undersurface of the optic chiasm. It also allows extracapsular dissection using binostril-bimanual technique and facilitates complete removal of these formidable tumors. In this report, we describe step-by-step, the technical details of the endonasal endoscopic transplanum transtuberculum approach with emphasis on the operative nuances for removal of retrochiasmatic craniopharyngiomas.

Extended endoscopic endonasal transsphenoidal approach for retrochiasmatic craniopharyngioma: Surgical technique and results.

Objective:Surgical treatment of retrochiasmatic craniopharyngioma still remains a challenge. While complete removal of the tumor with preservation of the vital neurovascular structures is often the goal of the treatment, there is no optimal surgical approach available to achieve this goal. Transcranial and transsphenoidal microsurgical approaches, commonly used in the past, have considerable technical limitations. The extended endonasal endoscopic surgical route, obtained by removal of tuberculum sellae and planum sphenoidale, offers direct midline access to the retrochiasmatic space and provides excellent visualization of the undersurface of the optic chiasm. In this report, we describe the technical details of the extended endoscopic approach, and review our results using this approach in the surgical management of retrochiasmatic craniopharyngiomas.Methods:Fifteen children, including 9 girls and 6 boys, aged 8 to 15 years underwent surgery using extended endoscopic transsphenoidal approach between 2008 and 2014. Nine patients had a surgical procedure done previously and presented with recurrence of symptoms and regrowth of their residual tumors.Results:A gross total or near total excision was achieved in 10 (66.7%) patients, subtotal resection in 4 (26.7%), and partial removal in 1 (6.7%) patient. Postoperatively, headache improved in 93.3%, vision recovered in 77.3%, and the hormonal levels stabilised in 66.6%. Three patients (20%) developed postoperative CSF leaks which were managed conservatively. Three (20%) patients with diabetes insipidus and 2 (13.3%) with panhypopituitarism required long-term hormonal replacement therapy.Conclusions:Our early experience suggests that the extended endonasal endoscopic approach is a reasonable option for removal of the retrochiasmal craniopharyngiomas. Compared to other surgical approaches, it provides better opportunities for greater tumor removal and visual improvement without any increase in risks.

Pilonidal sinus disease

Pilonidal disease is a frequent suppurative condition that occurs twice as often in men as in women, usually between the ages of 15 and 30. Pilonidal disease is located beneath the skin of the sacro-coccygeal region. It presents acutely as an abscess under tension while the chronic form gives rise to intermittent discharge from pilonidal sinus(es). Diagnosis is clinical and usually straightforward. In the large majority of cases, treatment is surgical but there is no consensus as to the 'ideal' technique. Acute abscess must be evacuated and an off-midline incision seems preferable. Excision is the standard definitive treatment but the choice of wide versus limited excision depends on the school of thought. The widespread practice in France is to leave the wound open, relying on postoperative healing by secondary intention. This technique has a low rate of recurrence but has the disadvantages of requiring local nursing care; the healing process is prolonged, usually associated with a temporary but prolonged cessation of activity. Primary wound closure techniques are less restrictive but their recurrence rate is probably higher. A direct midline suture is best after a small excision, but for a more extended wound, plastic reconstruction techniques are preferred; data in the literature favor asymmetric closure techniques such as those described by Karydakis and Bascom.

Rerum magistra experientia est: The Evolution of Modern Endoscopic Endonasal Skull Base Surgery and Reconstruction Techniques

istorically, surgical management of suprasellar lesions has been done by different transcranial approaches H including the subfrontal, frontolateral, and pterional routes. Nevertheless, in the past decades, the evolution of the transsphenoidal technique and the technological progress has favored the introduction and diffusion of the extended transsphenoidal approaches to the skull base. This was first described by Weiss (19), creating a paradigm in transsphenoidal surgery, with opening a new corridor to the suprasellar space. The transtuberculum-transplanum approach provides a direct route to the sellar suprasellar area, ensuring unrivalled visualization of the undersurface of the optic chiasm, third ventricle, pituitary stalk, and hypothalamus. The close visualization of the infrachiasmatic perforators from the carotid, the basilar, the posterior cerebral, and the posterior communicating arteries ensure a direct bimanual tumor dissection of critical neurovascular structures. Finally, the transtuberculum-transplanum pathway provides a direct midline and minimally invasive approach to the suprasellar region, without any brain retraction.

Interhemispheric transcallosal approach for resection of intraventricular central neurocytoma

The interhemispheric transcallosal approach is a versatile approach to access intraventricular tumors of the lateral and third ventricles. The advantages of using a transcallosal approach over a classical transcortical approach include a direct midline orientation with symmetrical access to both lateral ventricles and both walls of the third ventricle. In addition, violation of the cerebral cortex and the risk of postoperative seizures can be avoided. Central neurocytomas are rare benign tumors that represent approximately 0.1 to 0.5% of all primary brain tumors. They are typically located in the lateral ventricles and tend to present clinically with hydrocephalus. Currently, surgical removal with a gross-total resection is the treatment of choice. In this operative video manuscript, the author demonstrates an illustrative step-by-step technique for microsurgical resection of a large central neurocytoma involving both lateral ventricles in a patient with hydrocephalus using the interhemispheric transcallosal approach. A complete removal was performed without the need for permanent shunting. The operative technique and surgical nuances, including the surgical approach, intraventricular tumor removal, and closure are illustrated in this video atlas. The video can be found here: http://youtu.be/KzC8QYsTKeg. (http://thejns.org/doi/abs/10.3171/2013.V1.FOCUS12353)

Considerations of a Midline Posterior Approach to the Ankle and Subtalar Joints

The standard incisional approaches for ankle and subtalar joint surgery include the medial, lateral, or anterior. However, in patients with a history of traumatic injuries or previous surgery, in which the soft tissues of the foot and ankle have been compromised, a direct midline posterior approach might be preferable. The approach offers unparalleled exposure, provides excellent frontal plane visualization, and reduces the risk of vascular compromise by preserving the surrounding angiosomes. We report on 2 separate cases in which a midline posterior approach to the ankle and subtalar joints was used successfully for fusion procedures of the tibiocalcaneal and subtalar joints.

Surgical nuances for removal of tuberculum sellae meningiomas with optic canal involvement using the endoscopic endonasal extended transsphenoidal transplanum transtuberculum approach

Tuberculum sellae meningiomas frequently extend into the optic canals. Radical tumor resection including the involved dural attachment, underlying hyperostotic bone, and intracanalicular tumor in the optic canal offers the best chance of a Simpson Grade I resection to minimize recurrence. Decompression of the optic canal with removal of the intracanalicular tumor also improves visual outcome since this portion of the tumor is usually the cause of asymmetrical visual loss. The purely endoscopic endonasal extended transsphenoidal approach offers a direct midline trajectory and immediate access to tuberculum sellae meningiomas without brain retraction and manipulation of neurovascular structures. Although the endoscopic approach has been previously criticized for its inability to remove tumor within the optic canals, complete Simpson Grade I tumor removal including intracanalicular tumor, dural attachment, and involved hyperostotic bone can be achieved in properly selected patients. Excellent visualization of the suprasellar region and the inferomedial aspects of both optic canals allows for extracapsular, extraarachnoid dissection of the tumor from the critical structures using bimanual microsurgical dissection. In this report, the authors describe the operative nuances for removal of tuberculum sellae meningiomas with optic canal involvement using a purely endoscopic endonasal extended transsphenoidal (transplanum transtuberculum) approach. They specifically highlight the technique for endonasal bilateral optic nerve decompression and removal of intracanalicular tumor to improve postoperative visual function, as demonstrated in 2 illustrative cases. Special attention is also given to cranial base reconstruction to prevent CSF leakage using the vascularized pedicled nasoseptal flap.

Surgical nuances for removal of retrochiasmatic craniopharyngioma via the endoscopic endonasal extended transsphenoidal transplanum transtuberculum approach

Retrochiasmatic craniopharyngiomas are challenging tumors to remove given their deep location and proximity to critical neurovascular structures. Complete surgical removal offers the best chance of cure and prevention of recurrence. The endoscopic endonasal extended transsphenoidal approach offers direct midline access to the retrochiasmatic space through a transplanum transtuberculum corridor. Excellent visualization of the undersurface of the optic chiasm and hypothalamus can be obtained to facilitate bimanual extracapsular dissection to permit complete removal of these formidable tumors. In this report the authors review the endoscopic endonasal extended transsphenoidal approach, with specific emphasis on technical operative nuances in removing retrochiasmatic craniopharyngiomas. An illustrative intraoperative video demonstrating the technique is also presented.

Drosophila hedgehog signaling and engrailed - runt mutual repression direct midline glia to alternative ensheathing and non-ensheathing fates

Drosophila hedgehog signaling and engrailed - runt mutual repression direct midline glia to alternative ensheathing and non-ensheathing fates

Surgical nuances for removal of retrochiasmatic craniopharyngiomas via the transbasal subfrontal translamina terminalis approach

Giant craniopharyngiomas in the retrochiasmatic space are challenging tumors, given the location and surrounding vital structures. Surgical removal remains the first line of therapy and offers the best chance of cure. For tumors with extension into the retrochiasmatic space, the authors use the translamina terminalis corridor via the transbasal subfrontal approach. Although the lamina terminalis can be accessed via anterolateral approaches (pterional or orbitozygomatic), the surgical view of the optic chiasm is oblique and prevents adequate visualization of the ipsilateral wall of the third ventricle. The transbasal subfrontal approach, on the other hand, offers the major advantage of direct midline orientation and access to the third ventricle through the lamina terminalis. This provides the significant advantage of visualization of both walls of the third ventricle and hypothalamus as well as inferior midline access to the interpeduncular cistern to permit safe neurovascular dissection and total tumor removal. In this report, the authors describe the transbasal subfrontal translamina terminalis approach, with specific emphasis on technical surgical nuances in removing retrochiasmatic craniopharyngiomas. An illustrative video demonstrating the technique is also presented.