Occipital encephalocele: a retrospective analysis and assessment of post-surgical neurodevelopmental outcome.

BACKGROUND: Encephalocele represent a group of disorders which is characterised by extracranial herniation of the leptomeninges, brain, and CSF through a structural defect in the cranium. They are usually associated with other intracranial anomalies which may impact the neurological development. AIM: This study aimed to assess the predictors of neurological development of patients undergone surgical excision of occipital encephalocele. METHODS: All patients with occipital encephaloceles operated over the last decade (2012-2022). The sac size, presence of hydrocephalous, and associated anomalies were noted. The biopsy of these patients were reviewed and categorised as those which contains mature neural tissue and those without. The neurological outcomes were assessed by social, language, cognitive, and motor milestone and has been stratified into no delay, mild (1 of 4), moderate (2 or 3 of 4), and severe development delay (4 of 4). RESULTS: Total of 35 patients were included with median age of 10 months (IQR = 5-20 months). Fifteen (42.9%) patients had sac size of ≥ 5 cm, and 23 (65.7%) patients had mature neural tissues on biopsy. The median follow-up period was 6.4 years (IQR = 4.38-10.65) years. Seventeen (49.6%) patients had moderate to severe developmental delay. The sac size of ≥ 5 cm (AOR = 33.5; 95%CI = 3.35-334.8) (p = 0.003) and presence of mature neural content in the sac (AOR = 13.32; 95%CI = 1.1-160.36) (p = 0.041) were associated with significant neurodevelopmental delay. CONCLUSION: The presence of a large sac of ≥ 5 cm and the presence of mature neural tissues on histopathological specimen of patients with encephalocele point towards the possibility of poor neurological development.

Outcomes following surgical clipping of re-ruptured previously untreated intracranial aneurysms.

Re-rupture of untreated intracranial aneurysm is a potentially life-threatening condition. Despite tremendous advances in the diagnosis and treatment of intracranial aneurysms, such events are not rare and continue to pose a management dilemma. In this study, we examined the clinical, radiological and treatment details of patients who underwent microsurgical clipping for re-rupture of previously untreated intracranial aneurysms. Re ruptures were categorized as early and late re ruptures (< or > 7 days of inter ictus interval respectively). Modified Rankin Score (mRS) was used for functional outcome assessment and logistic regression analysis was used to test the predictors of long-term outcome. Re-ruptured intracranial aneurysms comprised 5% (n = 32/637) of the aneurysm clippings done at our center in this time span. The mean mRS score at discharge and at last follow-up were 3 and 3.04 respectively. Twenty-four (75%) patients were alive at a mean follow-up of 36 months. Early re-ruptures were associated with worse mean mRS scores at discharge (3.9 vs 2.5, p = 0.03) including the perioperative deaths (n = 4, 12.5%). The functional status at discharge and a poor preoperative clinical grade predicted a poor long-term outcome. Therefore, the long-term outcomes are primarily dependent on the short-term outcomes and to a lesser extent, the clinical grade at presentation. Those presenting with poor preoperative clinical grade, especially in the setting of an early re rupture, have a very poor prognosis and do not benefit from surgery.

Under recognized yet a clinically relevant impact of aneurysm location in Distal Anterior Cerebral Artery (DACA) aneurysms: insights from a contemporary surgical experience.

Aneurysms of the distal anterior cerebral artery (DACA) are rare but surgically challenging. Despite a known therapeutic implication of the aneurysm location on the DACA territory, the literature is unclear about its clinical and prognostic significance. Our surgical experience over the last 5 years was reviewed to compare the clinical, operative, and outcome characteristics between aneurysms located below the mid portion of the genu of the corpus callosum (called proximal aneurysms) to those distal to this point (called distal aneurysms). A prognostic factor analysis was done using uni and multivariable analysis. A total of 34 patients were treated (M: F = 1:2.3). The distal group had a higher frequency of poor clinical grade at presentation (n = 9, 47.4%) in contrast to (n = 2, 13.3%) proximal aneurysms (p = 0.039). Despite an overall tendency for a delayed functional improvement in these patients, the results were mainly due to favorable outcomes in the proximal group (favourable functional outcomes at discharge and at last follow-up being 80% and 86.7% respectively). On the multivariable analysis, only WFNS grade (> 2) at presentation (OR = 13.75; 95CI = 1.2-157.7) (p = 0.035) and application of temporary clips (AOR = 34.32; 95CI = 2.59-454.1) (p = 0.007), both of which were more in the distal group, independently predicted a poor long term functional outcome. Thus, the aneurysm location impacts the preoperative clinical grade, the intraoperative aneurysm rupture risk rate as well as the temporary clipping requirement. A combination of these factors leads to worse short and long-term functional outcomes in the distal DACA aneurysms.

How I do it-Dolenc approach for clipping of ventral wall paraclinoid ICA aneurysm.

BACKGROUND: Ventral wall ICA aneurysms are a type of Paraclinoid aneurysms which arise from ventral surface of ICA opposite to the origin of the ophthalmic artery. These are technically challenging owing to its close proximity to the anterior clinoid process, difficulty in getting proximal control, difficulty in preserving ophthalmic artery and maintaining the patency of ICA. METHOD: A 38 year old patient with a Ventral wall ICA aneurysm by Dolenc approach. CONCLUSION: Tailored dural peeling and extradural anterior clinoidectomy exposes proximal part of Paraclinoid ICA allowing better proximal control and a wider exposure, which is crucial for clipping these aneurysms.

How I do it: Exoscope assisted microsurgical ligation of type 1 spinal dural arteriovenous fistula.

BACKGROUND: Type 1 Spinal dural arteriovenous fistula (dAVF) is a rare but curable vascular cause of myelopathy. Microneurosurgery is a very efficacious modality in treating them. METHOD: A 26 year old gentleman with progressive flaccid paraparesis (LMN type) and urinary incontinence underwent surgery using exoscope for a right side T9-10 dAVF. A dilated vein was seen accompanying the exiting nerve root intraoperatively, consistent with the preoperative angiographic findings. The vein was ligated and divided leading to restitution of spinal cord vasculature on table and excellent postoperative outcome. CONCLUSION: Surgical resection is a straightforward and highly effective treatment in spinal dAVF.

Anterior clinoidectomy in low lying internal carotid artery-posterior communicating artery aneurysm.

BACKGROUND: At times, a regulation internal carotid artery-posterior communicating artery junction (ICA-P-Comm) aneurysm becomes a surgical hurdle owing to its close proximity to the anterior clinoid process, an immovable ICA and a concealed dominant P-Comm artery arising from the aneurysm neck. METHOD: A 70 year old patient with a low lying ICA-P-Comm aneurysm underwent a "tailored" intradural clinoidectomy for aneurysm clipping. CONCLUSION: A tailored anterior clinoidectomy to expose "just enough" allows a proximal ICA control in a suitable area, mobility of an atherosclerotic ICA and exposes the P-Comm artery origin which are essential in safe clipping of these aneurysms.

Aspergillus infections of lateral skull base: a case series.

PURPOSE: While extensive research with accurate classification has been done in mycoses of the paranasal sinuses and anterior skull base, a similar understanding of lateral skull base fungal pathologies is lacking due to relative rarity and diagnostic difficulties. We introduce a series of eleven cases and two different invasive entities of Aspergillus temporal bone diseases-fungal skull base osteomyelitis (SBO)/malignant otitis externa (MOE) and chronic invasive granulomatous fungal disease (CIGFD). METHODOLOGY: A retrospective observational study was conducted at the neuro-otology unit of a tertiary care referral center between July 2017 and November 2022. Diagnosed cases of lateral skull base osteomyelitis with atypical symptoms and lack of response to culture-directed antibiotics were evaluated for fungal origin. Patient data, including history, laboratory findings, serum galactomannan assay, CT and MRI imaging findings, clinical examination findings, and co-morbidities, were analyzed. The treatment course and response were assessed. RESULTS: A total of 11 cases were included in the study. Of these, 9 were cases of Aspergillus-induced skull base osteomyelitis (SBO) and 2 of Aspergillus-induced chronic invasive granulomatous fungal disease (CIGFD). CIGFD presented with persistent ear discharge and slowly progressive post-aural swelling, while all patients of fungal SBO had lower cranial nerve palsies. CIGFD responded to excision and antifungals, while SBO responded well to conservative anti-fungal treatment. CONCLUSION: In cases of lateral SBO not responding to antibiotic therapy, the possibility of fungal etiology should be considered. Aspergillus spp. seems to be the major fungal pathogen.

Temporal profile of serum melatonin levels in paediatric pineal tumours subjected to surgery: newer insights.

INTRODUCTION: Pineal tumours (PTs) are rare and histologically variable. Serum melatonin is a well-known product of this gland, albeit with uncertain clinical implications vis-à-vis its utility as a potential tumour marker. In particular, the temporal profile of serum melatonin during the disease course remains unclear and infrequently studied. METHODS: Ten children with pineal tumours were prospectively studied over 2 years. Midnight serum melatonin levels were estimated before and after surgery (6-week postoperatively) and at the time of clinical-radiological progression. Different clinical, radiological, histological and treatment variables were correlated with the mean change in the pre- and postoperative serum melatonin levels using statistical methods. RESULTS: Histopathologically, 5 of these cases (50%) were pineal cell tumours, while the rest were tumours of non-pineal cell origin. The mean preoperative serum melatonin level was 94.9 pg/ml (range 20-397 pg/ml), while the mean postoperative level was 69.6 pg/ml (range 45-156 pg/ml; in one case, the levels became non-detectable). Tumour histology (p = 0.04) and gender (p = 0.03) correlated with high preoperative serum levels. While the change in overall mean value did not have any statistical significance (effect size 0.29, p value 0.340), postoperative serum melatonin elevation was significant in tumours of non-pineal cell origin (large effect size 0.93, p value 0.004). CONCLUSION: The serum melatonin may be affected by age, gender and symptom duration. However, the dynamic of serum melatonin in the perioperative period is largely dependent on the cell of origin of the PT.

Contralateral supraorbital eyebrow approach for tuberculum sellae meningioma.

BACKGROUND: The main challenge in tuberculum sellae meningioma (TSM) resection is the safe dissection of the optic nerves, which many a times are compressed and distorted by the tumor. While intuitive, an approach from the side of predominant tumor extension makes tumor dissection from the medial surface of the ipsilateral optic nerve rather blind. We describe here a contralateral supraorbital eyebrow approach (c-SEA) to address this "blind spot." METHOD: c-SEA was performed using a 2 × 2 cm craniotomy. The patient improved after surgery and postoperative imaging confirmed the totality of the tumor resection. CONCLUSION: c-SEA can be an excellent minimally invasive option for asymmetric TSM.

"Undercutting of the corresponding rib": a novel technique of increasing the length of donor in intercostal to musculocutaneous nerve transfer in brachial plexus injury.

Intercostal nerves (ICN) are often utilized as donors for various neurotization procedures in brachial plexus injuries. ICN to musculocutaneous nerve (MCN) transfer is usually a standard in pan brachial plexus injuries, in order to restore flexion at the elbow. A tensionless co-aptation of the donor-recipient nerves often necessitates either a distal dissection of the ICNs where the number of fascicles is rather low or a proximal dissection, often at the cost of dissection of the serratus anterior digitation with a risk of later fibrosis and adhesion. We report two cases of pan brachial plexus injuries where ICN-MCN transfer was performed to restore elbow function. These patients underwent clinical and electrodiagnostic evaluation before surgery. We used the standard technique of harvesting ICNs 3-5, with our technical modification of "undercutting of rib" for increasing the donor length. The procedure was applied in two patients with pan brachial plexus injury (mean age = 23). Mean duration since the injury to surgery was ten months. Both patients underwent tensionless anastomosis with a combination of suture and fibrin glue co-aptation. While one patient had some improvement in elbow flexion, another one was under active rehabilitation protocol during follow-up. We found that undercutting of the ribs near serratus digitations can allow mobilization of the ICN from its groove, which in turn lengthens the donor nerve length without violating the serratus anterior digitations and without too anterior dissection of the nerve. It can be a viable option when a tensionless co-aptation at the axilla is otherwise not feasible intraoperatively.

Insular glioblastoma: surgical challenges, survival outcomes and prognostic factors.

BACKGROUND: Insular gliomas are unique, challenging and evoke a lot of interest amongst neurosurgeons. Publications on insular glioma generally focus on the surgical intricacies and extent of resection pertaining to the low-grade gliomas. Insular glioblastomas (iGBM) have not been analysed separately before. METHODS: Histologically proven WHO grade IV gliomas involving the insula over a 9-year period were studied. Their clinical presentation, radiological features, surgical findings and survival outcomes were assessed. Statistical methods were used to determine the favourable predictors of survival. RESULTS: Out of 27 patients (M:F = 2.9:1), 18 (66%) patients had a tumour extension beyond the insula, 10 (37%) of whom had basal ganglia involvement. Total, near total and subtotal excisions were performed in 7 (26%), 9 (33%) and 11 (40.7%) patients, respectively. Twenty-three patients had glioblastoma, while four had gliosarcoma. IDH mutation was negative in six of the seven patients where it was done. Median overall survival was 5 months. Multivariate analysis showed that a female gender (p = 0.013), seizures in the preoperative period (p = 0.048) and completion of adjuvant therapy (p = 0.003) were associated with a longer survival. CONCLUSION: Insular glioblastomas have a poor prognosis. Insular location and certain tumour characteristics often limit the extent of resection of iGBMs. Moreover, postoperative complications sometimes negate the advantages of a radical resection. A female gender, presentation with seizures and completion of adjuvant chemoradiotherapy appear to be good prognostic factors.

Non-aneurysmal subarachnoid hemorrhage: Is the deep venous system the hidden culprit?

AIM: The exact cause of bleeding in non-aneurysmal sub-arachnoid hemorrhage (SAH) is yet to be established. The present study intends to evaluate the morphological variants of deep cerebral venous drainage, especially basal veins of Rosenthal (BVR), and to correlate if such a venous anomaly is associated with increased incidence of non-aneurysmal SAH. METHODS: A prospective analysis of all the patients of age more than 12 years with spontaneous non-aneurysmal SAH and undergone 4-vessel DSA for the diagnosis of the source of bleeding was included in the study (n = 59). The anatomy of the basal venous distribution was evaluated and was divided into 3 different types, namely normal (Type A), normal variant (Type B), and primitive (Type C), based on DSA findings. The follow-up of these cases was noted. The three groups were compared with one another. RESULTS: The median age of presentation was 51 years with slight male predominance (52%). Primitive venous drainage was associated with a poorer grade at presentation (p = 0.002), more severe bleed (p = 0.001), vasospasm (p = 0.045), and a poorer outcome at 6 months (p = 0.019). Hydrocephalous and vasospasm were seen in patients with primitive venous drainage. On multivariate regression analysis for poorer outcome, it was observed that a worse grade at presentation, extensive bleed, primitive venous drainage are independent predictors of an adverse outcome. CONCLUSION: The presence of primitive venous drainage has a linear relationship with the development of non-aneurysmal SAH with multi-cisternal hemorrhage, worse grade at presentation, and unfavorable outcome.

"Extra-cranial proximal pica aneurysm - a rare and surreptious cause of posterior fossa sah: case report and review of literature".

BACKGROUND: Extra-cranial posterior inferior cerebellar artery (PICA) aneurysms are rare with only 22 cases been reported so far. Intra-dural type of extra-cranial PICA aneurysm is even rarer with few case reports available. We report a previously unreported type of proximal PICA aneurysm in which the PICA aneurysm had intra-dural location at the C2 vertebral level. CASE DESCRIPTION: A 51 year old gentleman presented with sub-arachnoid haemorrhage and intra-ventricular haemorrhage, predominantly involving the fourth ventricle and had no focal neurological deficit. CT angiogram was negative however a dedicated four vessel angiogram demonstrated an abnormal extracranial origin of right PICA at C1-C2 level, with associated aneurysm in its proximal segment. A C1 posterior arch excision with partial C2 laminectomy and clipping of the aneurysm was done. CONCLUSION: Aneurysm associated with extracranial intra-dural PICA origin is a rare cause of SAH, and may not be detected with CT angiography. Such cases often require dedicated four vessel angiography, with careful study for any possibility of extra-cranial aneurysm. This variant has important surgical implication and requires preservation of the Lateral spinal artery (LSA-PICA communication), and that such aneurysm approached only with posterior cervical exposure without the need of a craniotomy. Such cases remind us the need to have an in-depth understanding of the variations of the posterior circulation.

Constipation in degenerative cervico-thoracic spine myelopathy: a simple co-existence or a complex inter-relationship?

PURPOSE: Identify factors affecting constipation and post surgical improvement in patients of myelopathy. METHODS: Sixty-four patients with myelopathy due to extradural spine pathologies (47 cervical; 17 thoracic spine, male:female-5.4:1 with mean age 46.16) underwent evaluation including Bristol stool scale (BSS), PFT and uroflowmetry. All cases were evaluated by gastroenterologist to rule out any intrinsic bowel disease. Chi-square test, Kruskal-Wallis/Mann-Whitney U test and Wilcoxon signed rank test were employed to ascertain statistical significance. RESULTS: The presence of constipation was associated with male sex (p = 0.01), degree of constipation with duration bladder symptoms (p = 0.008) and numbness (p = 0.04). The improvement in BSS after surgery (p = 0.006) was associated with local pain (p = 0.02), duration of weakness (p = 0.04) and overall symptoms (p = 0.01), also with pulmonary function tests (p = 0.002) and pre-operative Nurick's grade (p = 0.01). CONCLUSION: Constipation is a myelopathic symptom as it is relieved by cord decompression and the gender, PFT and the duration of symptoms play an important role in defining constipation and expected improvement in these patients.

Recurrent or symptomatic residual posterior fossa hemangioblastomas: how are they different from their primary counterparts?

BACKGROUND: Posterior fossa hemangioblastomas are WHO grade I benign lesions with a surprisingly high recurrence rate. This study determines the factors responsible for recurrence and the clinico-radiological and histopathological differences between primary (group A; n = 60) and recurrent/symptomatic residual (group B; n = 24) tumors. METHODS: Radiologically, tumors were differentiated into cystic, cystic with a mural nodule, solid-cystic/microcystic and solid. Surgery was undertaken via a midline or lateral suboccipital approach. Histopathology differentiated them into reticular, cellular or mixed subtypes. RESULTS: Truncal-appendicular ataxia in group A and von Hippel-Lindau (VHL) disease and raised intracranial pressure in group B were the predominant presentations. VHL patients in group B had a longer duration of symptoms (median 72 months) than those with non-VHL recurrences (median: 36 months). Multicentric mural nodules (n = 9/24, 37.50%, P = 0.0001) and bilateral cerebellar hemispheric involvement (n = 6/24, 25%, P = 0.0003) were exclusively seen in the preoperative radiology of group B tumors. Brainstem involvement was seen in the tumors of ten (16.67%) patients in group A and six (25.00%) patients in group B. One subset of patients required several resurgeries for repeated recurrences. Abnormal vascular proliferation and papillary projections into adjacent brain, and highly cellular stroma were unique histological features at recurrence. Total resection was achieved in 45 group A and 19 group B patients. The outcome based on the Karnofsky performance scale (KPS) was assessed at follow-up at 6 weeks (A: n = 60, B: n = 24): KPS0: A = 4, B = 1; KPS10-40 (dependent): A: 4, B = 5; KPS50-70 (independent for daily needs): A = 36, B = 16; KPS80-100 (fully independent): A = 16; B = 2. CONCLUSIONS: In recurrent/residual tumors, the radiological as well as histopathological features showed a distinctive change toward a more aggressive nature. Higher incidences of multiple mural nodules, bilateral spread, remote recurrence and VHL disease at preoperative radiology; as well as proliferative angioarchitecture, an irregular brain tumor interface and highly cellular stroma at histology were found in these patients compared to their primary counterparts.

Simultaneous odontoid excision with bilateral posterior C1-2 distraction and stabilization utilizing bilateral posterolateral corridors and a single posterior midline incision.

A simultaneous odontoid decompression and bilateral posterior atlanto-axial facetal distraction, C1-2 joint spacer/bone graft placement and stabilization may be performed utilizing the 'posterior-only' approach. This procedure may be performed utilizing a single posterior midline incision, a bilateral posterior approach to the C1-2 facet joints and a bilateral posterolateral approach to the odontoid process and C2 body. It may be carried out in situations where a C1-2 non-reduction/partial reduction using a 'posterior alone' procedure is anticipated due to the complex bony/soft tissue configuration anterior at the thecal sac existing at the cervicomedullary junction. In the four cases described in this report, the procedure led to a successful circumferential decompression at the level of foramen magnum along with posterior C1-2 facetal distraction and stabilization in various complex craniovertebral junction anomalies (atlantoaxial dislocation [AAD] and/or a high basilar invagination [BI] associated with a significantly retroverted dens, along with a rotatory component, due to grossly asymmetrical facet joints). This technique may also be utilized in those diseases that result in an anterior osteoligamentous mass at the CVJ associated with C1-2 instability.

Surgery for superior hypophyseal artery aneurysms: A new classification and surgical considerations.

BACKGROUND: Superior hypophyseal artery (SHA) aneurysms form a unique subgroup of paraclinoid aneurysms having a propensity to grow to a large size in the suprasellar region resulting in compression of the optic nerve, chiasma, and/or tract. AIM: A new classification of SHA aneurysms is proposed that helps in identifying the surgical issues encountered during surgical clipping of these medially directed aneurysms located at different segments of the medial surface of the internal carotid artery (ICA). SETTINGS AND DESIGN: This descriptive study was conducted at a tertiary care university hospital. MATERIAL AND METHODS: In 14 patients operated for a SHA (mean age: 49.43 ± 11.28 years; presenting either with subarachnoid hemorrhage (n = 11; 78.57%) or mass effect (n = 3; 21.42%), 4 parameters having a bearing on surgery [a. size: (small <1 cm n = 5, large 1-2.5 cm n = 7, giant >2.5 cm n = 2); b. origin of SHA aneurysmal neck and direction of its fundus; c. relationship of the aneurysm to important neurovascular structures; and, d. whether the aneurysms were saccular or fusiform] were used to divide SHA aneurysms into 7 categories a. Antero-supero-medial (n = 2); b. Antero-infero-medial (n = 1); c. Supero-medial (n = 3); d. Infero-medial (n = 3); e. Postero-medial (n = 2); f. Fusiform (n = 1); and, g. Giant (n = 2). Modified Rankin Scale (MRS) score was utilized to assess outcome [favorable: mRS 0-2; unfavorable: mRS 3-6] at discharge and follow up. RESULTS: Modified Hunt and Hess grade at admission was 0 = 3; I = 3; II = 3; III = 2; IV = 3 (favorable mRS: 10; 71.42%; unfavorable mRS: 4; 28.57%); and, Fisher grade was I = 3; II = 6; III = 2; IV = 3. Twelve patients required anterior clinoid process drilling/carotid collar opening to facilitate optic nerve mobilization, for proximal ICA control, and to assess the proximal part of the neck of aneurysm for aneurysmal clipping (n = 13) or wrapping (n = 1). Fenestrated clip was applied in 5 patients. In the supero-medial group (antero-supero-medial, supero-medial, and postero-supero-medial), the aneurysmal fundus was found directly below the ipsilateral optic apparatus, elevating it; in the postero-supero-medial group, the fundus often lay in close proximity to A1 artery, Heubner's recurrent artery, ICA bifurcation, or dorsum sellae. Optic pathway, hypothalamic, and medial lenticulostriate perforators also required careful separation. Antero-infero-medial SHA aneurysm was hidden from view, embedded in the anterior wall of sella below tuberculum sellae. At a median follow-up of 17.5 ± 26.78 months (range: 8-84 months), 9 (64.28%) patients had a favorable mRS and 5 (35.71%) an unfavorable one. CONCLUSION: Systematically classifying SHA aneurysms and anticipating the surgical risk based upon their anatomical variations helps in achieving a good surgical outcome.

Craniovertebral junction anomalies: When is resurgery required?

BACKGROUND: Craniovertebral junction (CVJ) abnormalities, such as atlantoaxial dislocation (AAD) with or without basilar invagination (BI), with or without associated Chiari malformation (CM), may cause a high cervical myelopathy. Occasionally, mechanical factors such as inadequate canal decompression, torticollis, and/or scoliosis may lead to lack of improvement following the primary surgery. Furthermore, implant-related factors, requiring implant revision/removal, or the presence of surgical site infections may cause the patient to undergo resurgery. AIMS: This study was aimed at highlighting the underlying etiopathogenesis of resurgery following the primary surgery undertaken in CVJ abnormalities. SETTING AND DESIGN: This was a retrospective study from a tertiary care referral institute focusing on 414 operated cases of CVJ anomalies. MATERIALS AND METHODS: The data of 55 patients who underwent resurgery included their clinicoradiological assessment and operative records. The inclusion criteria included failed primary procedure, repeat procedure for construct failure, infection at the surgical site, or wound dehiscence. Pure CM patients without bony anomalies were excluded from the study. RESULTS: A total of 137 procedures were performed in 55/414 (13%) patients. Causes of resurgery could be divided into ventral [redo or denovo transoral decompression (TOD) or wound-related complications, n = 33, 40.2%] and dorsal causes (implant-related factors/wound infections, n = 49, 59.8%). De novo TOD was done in persisting myelopathy following posterior fusion (PF) with C1-2 distraction (n = 15,18.3%,). Redo TOD was done for residual anterior bony compression [n = 8, 9.6%, OR 0.61; [CI = 0.20-1.86]. Causes for oral wound reexplorations (n = 10, 12.2%) included velopharyngeal insufficiency, wound resuturing, oral bleeding, and cerebrospinal fluid (CSF) leak. Dorsal causes included: (A) Implant factors (n = 27, 32.7%) and (B) neck wound reexplorations (n = 22, 26.8%). Presence of subaxial spine scoliosis, torticollis, and asymmetric joints increased the incidence of reexploration. Occipitocervical fusion rather than C1-2 fusion was more prone towards construct loosening. CONCLUSIONS: Patients undergoing distraction with PF may require transoral surgery due to persisting myelopathy, especially in the presence of torticollis, scoliosis, and symmetrical joints. Single stage TOD+PF increases the chances of implant infection due to tissue contamination, bacteremia, or transfacetal migration of microbes. Chronic/recurrent sinus is usually a harbinger of deeper infection and can be cured with implant removal.