The “Three on a Stick” Incision—A Curvilinear Solution for the Occipital and Suboccipital Region

BACKGROUND Different conditions of the posterior fossa such as Chiari malformations, tumors, and arachnoid cysts require surgery through a suboccipital approach, for which a typical midline vertical linear incision is used. Curvilinear incisions have been carried in all other scalp regions other than the sub region for better cosmetic outcomes; a vertical curvilinear incision in the occipital and suboccipital region has not been reported. OBJECTIVE To evaluate the cosmetic value and safety of the “3 on a stick” vertical suboccipital curvilinear incision. METHODS We compared curvilinear to linear incisions, considering the scar's width, color, how conspicuous, and how well the scar could be covered by hair naturally. RESULTS Between 2010 and 2016, 68 children with Chiari I malformation were surgically intervened. The curvilinear incision was performed in 56 (82.4%) while a linear incision in 12 (17.6%) children. There were only 2 (2.9%) wound related complications (superficial dehiscences) in the curvilinear group and 1 additional dehiscence in a linear incision case. There were no neural or vascular complications. Scars were very similar among the 2 groups; both were equally conspicuous but curvilinear ones seemed to get covered better by hair. CONCLUSION The “3 on a stick” curvilinear incision of the suboccipital region is safe and allows for better hair coverage of the scar. It can be used for multiple conditions requiring a midline suboccipital or even occipital approach, such as Chiari malformations, tumors, and cysts.

History, Variations, and Extensions of the Retrosigmoid Approach: Anatomical and Literature Review

The retrosigmoid approach is the workhorse for posterior fossa surgery. It gives a versatile corridor to tackle different types of lesions in and around the cerebellopontine angle. The term “extended” has been used interchangeably in the literature, sometimes creating confusion. Our aim was to present a thorough analysis of the approach, its history, and its potential extensions. Releasing cerebrospinal fluid from the subarachnoid spaces and meticulous microsurgical techniques allowed for the emergence of the retrosigmoid approach as a unilateral variation of the traditional suboccipital approach. Anatomical landmarks are helpful in localizing the venous sinuses and planning the craniotomy, and Rhoton's rule of three is the key to unlock difficult neurovascular relationships. Extensions of the approach include, among others, the transmastoid, supracerebellar, far-lateral, jugular foramen, and perimeatal approaches. The retrosigmoid approach applies to a broad range of pathologies and, with its extensions, can provide adequate exposure, obviating the need for extensive and complicated approaches.

Utility of indocyanine green in the detection of radiologically silent hemangioblastomas: case report

Hemangioblastomas (HBs) are rare, benign, hypervascularized tumors. Fluorescent imaging with indocyanine green (ICG) can visualize tumor angioarchitecture. The authors report a case of multiple HBs involving two radiologically silent lesions only detected intraoperatively by ICG fluorescence. A 26-year-old woman presented with a cystic cerebellar mass on the tentorial surface of the left cerebellar hemisphere on MRI. A left paramedian suboccipital approach was performed to remove the mural nodule with the aid of ICG injection. The first injection, applied just prior to removing the nodule, highlighted the tumor and vessels. After resection, two new lesions, invisible on the preoperative MRI, surprisingly enhanced on fluorescent imaging 35 minutes after the ICG bolus. Both silent lesions were removed. Histological analysis of all three lesions revealed they were positive for HB. The main goal of this report is to hypothesize possible explanations about the mechanism that led to the behavior of the two silent lesions. Intraoperative ICG videoangiography was useful to understand the 3D angioarchitecture and HB flow patterns to perform a safe and complete resection in this case. Understanding the HB ultrastructure and pathophysiological mechanisms, in conjunction with the properties of ICG, may expand potential applications for their diagnosis and future treatments.

Lateral Suboccipital Approach in Semisitting Position for Resection of Vagal Schwannoma: 2-Dimensional Operative Video

We present a case of a sizeable vagal schwannoma that was resected through a lateral suboccipital approach in semisitting position. An extra-axial lesion, occupying the left cerebellomedullary cistern and extending from the pontomedullary junction to the jugular foramen was incidentally discovered in a 40-year-old woman afflicted with secondary progressive multiple sclerosis during repeated magnetic resonance imaging (Fig. 1). On physical examination, a mild deviation of the uvula to the right and a diminished gag reflex were observed. The patient was referred to our department after considerable growth of the lesion was noted and a broad interdisciplinary consensus was reached to treat the lesion surgically.A gross total resection was achieved, histopathology confirmed a WHO I schwannoma with a low proliferation index. Postoperative dysphonia resolved completely within a few weeks, there was no collateral neurological deficit and especially no functional dysphagia. At 3-year follow-up, there was no indication of residual or recurrence.This 2-dimensional video demonstrates pre- and postoperative imaging, positioning and set-up of operating room, anatomical and surgical nuances of the skull base approach, and the operative technique for microdissection of the schwannoma from the critical neurovascular structures (Fig. 2).In summary, the lateral suboccipital approach in semisitting position is a powerful tool in the armamentarium for the microsurgical management of various pathologies residing in the posterior cranial fossa, especially large and vascularized schwannomas. Provided the necessary anesthesiological precautions and intraoperative procedures the semisitting position is safe and effective.The link to the video can be found at: https://youtu.be/-9o_qJGkQhg.

Trapping and Thrombectomy of Giant Thrombosed Vertebral Artery Aneurysm via Bilateral Subocciptal Approach – Technical Note

Background: Giant aneurysms arising from the vertebral artery (VA) are rare; they represent 4% to 6% of all intracranial giant aneurysm. The natural history of thrombosed aneurysms is extremely poor. Most such lesions progressively enlarge and result in irreversible progression of neurological deficits and fatal sequelae through resultant compression of the brainstem. We present the clinical experience of giant thrombosed vertebral artery aneurysm successfully treated via a bilateral suboccipital approach. A 62 –year-old woman presented with slight dysarthria and ataxia for one year. Neurological examination showed right lateral gaze nystagmus, bilateral absent corneal reflex, absent gag reflex, bilateral dysdiadochokinesia, poor right finger nose test, and slightly poor tandem gait. MRI showed a 27 mm giant thrombosed left VA aneurysm with brain stem compression. We performed trapping of the aneurysm and thrombectomy through a bilateral suboccipital approach. First, the distal portion was clipped from the left side. Next, the proximal portion was approached from the right side. Thrombectomy was performed and after shrinkage of the aneurysm, the clips were applied involving some part of the aneurysm just distal to PICA. Conclusion: The optimum treatment for aneurysm of this type is thought to be complete obliteration of the parent artery with trapping and thrombectomy to decompress the brainstem. Sometimes if PICA could not be preserved Occipital artery (OA)-PICA bypass should be considered.

Posterior Fossa Mid-Line Space Occupying Lesions Diagnosis and Surgical Outcome

Background posterior fossa tumors are more common in children that in adults. Between 54% and 70% of all childhood brain tumors originate in the posterior fossa. About 15-20% of brain tumors in adults occur in the posterior fossa. Certain types of poeterior fossa tumors, such as medulloblastoma, pineoblastoma, ependymomas, primitive neuroectodermal tumors, and astrocytomas of the cerebellum and brain stem, occur more frequently in children. Aim of the Work the aim of this study was to review the preoperative diagnostic modalities, surgical procedures and outcome for different midline posterior fossa space occupying lesions. Patients and Methods this is retrospective study has been conducted on 50 patients with posterior fossa midline space occupying lesions during the period March 2013 to October 2015, at Department of Neurosurgery, Ain Shams University. All Patients have been subjected to preoperative clinical assessment; thorough history taking, complete general and neurological examination according to Ain Shams University neurosurgical sheet. Results this study was conducted on 50 patients with midline posterior fossa space occupying lesions. All of them underwent a midline suboccipital approach. The pre and post-operative data were collected and analyzed. This study included 50 patient, 26 female (52%) and 24 male (48%) patients. The mean age ranges from 1 year to 60 years. Conclusion surgery is the treatment of choice for the cases of posterior fossa mid line lesions especially in children and adolescents to decreases the risk of disabilities and increases the survival.