Author Response.

How to cite this article: Vaithialingam B, Gopal S, Masapu D. Author Response. Indian J Crit Care Med 2024;28(1):87-88.

Correlation between choroid plexus carcinoma and Li-Fraumeni syndrome: implications of TP53 mutations and management strategies-a case-based narrative review.

BACKGROUND: Choroid plexus carcinomas (CPCs) are rare, aggressive grade 3 tumors of the central nervous system associated with Li-Fraumeni syndrome (LFS) in a notable percentage of cases due to TP53 germline mutations. Understanding the correlation between CPCs and LFS is crucial for tailored management strategies. However, distinguishing CPCs from benign choroid plexus papillomas (CPPs) remains challenging, relying largely on histologic features. This study aimed to explore the association between CPCs and LFS, emphasizing the impact of TP53 mutations on diagnosis, treatment, and clinical outcomes. MATERIALS AND METHODS: Scientific databases such as PubMed, Scopus, and Web of Science were systematically searched up to January 2024 using keywords related to CPCs, LFS, TP53 mutation, and central nervous system tumors. Selection criteria included studies investigating the link between CPCs and LFS, their management approaches, and genetic implications of TP53 mutations. Ten relevant studies were selected for analysis after screening titles, abstracts, and full-text articles. Data extraction focused on clinical, genetic, and management factors related to CPCs associated with LFS. RESULTS: The review highlighted the strong association (36%) between CPCs and LFS, primarily due to TP53 germline mutations. Studies emphasized the need for genetic testing in patients with CPCs, especially in pediatric cases, to identify LFS implications. Furthermore, the impact of TP53 mutations on treatment strategies was emphasized, recommending irradiation-sparing therapies due to inferior survival rates associated with radiotherapy in LFS patients with CPCs. Cases illustrated the challenges in diagnosing CPCs and the importance of immunohistochemistry and genetic testing for TP53 mutations. CONCLUSION: CPCs pose challenges in diagnosis and management, particularly in distinguishing them from benign tumors. The association with LFS, often due to TP53 germline mutations, underscores the importance of genetic testing for early detection and tailored treatment strategies. Irradiation-sparing therapies are recommended for LFS-associated CPCs to mitigate the risk of secondary malignancies. Comprehensive profiling of CPC patients, especially in pediatric cases, is crucial for early detection and management of potential secondary cancers associated with LFS.

Cases of Mixed Schwannoma-Meningioma With and Without Neurofibromatosis 2 with Emphasis on Tumorigenesis.

Concurrent occurrence of schwannoma and meningiomas are rare, and are found especially in association with neurofibromatosis type 2 (NF2). Occurrence of mixed tumor without the aforementioned conditions is extremely rare. We present three cases of mixed tumor in different locations, including two with NF2 and one without NF2. We analyse the relationship of mixed tumor with NF2 and its clinical implications. Presence of mixed schwannoma-meningioma should prompt screening for NF2. Thus aids in early diagnosis of unsuspected NF2 cases. We observed that irrespective of different locations, cases with NF2 showed frequent recurrence of schwannoma as compared to case who did not fit in the existing clinical criteria for NF2. Collision tumor and thereby NF2 mutations indicates the prognosis and recurrence of the tumor, thereby guides in deciding the management.

Spring-Assisted Cranial Expansion for Multisuture Craniosynostosis: First Case Report from the Indian Subcontinent.

We present a first use case report from the Indian subcontinent of a 5-month-old child with multisuture craniosynostosis with raised intracranial pressure managed by spring-assisted cranial expansion followed by traditional fronto-orbital advancement and cranial vault remodeling. We emphasize the advantages of spring-assisted cranial expansion in extremely young infants with raised intracranial pressure over posterior vault distraction osteogenesis and open posterior vault remodeling.

Anesthetic management of super-selective intra-arterial Melphalan injection in an infant with retinoblastoma.

Intra-arterial Melphalan injection is an emerging treatment for children with advanced retinoblastoma. The procedure, which is frequently performed under general endotracheal anesthesia, can be complicated by technical difficulty and cardiorespiratory instability, which the anesthesiologist should be aware of. We describe the anesthetic management and special concerns during super-selective intra-arterial Melphalan injection in an infant with advanced retinoblastoma.

"Locked-in State" Following Anterior Circulation Aneurysmal Subarachnoid Hemorrhage.

How to cite this article: Vaithialingam B, Gopal S, Masapu D. "Locked-in State" Following Anterior Circulation Aneurysmal Subarachnoid Hemorrhage. Indian J Crit Care Med 2023;27(8):601-602.

Catheter Embolization of an Orbital Arteriovenous Fistula in a Patient With Wyburn-Mason Syndrome.

A 24-year-old female presented to the emergency department with swelling of the forehead and oculus sinister. A soft, compressible glabellar swelling with proptosis of the oculus sinister was noted on clinical examination. Cerebral angiography revealed a left medial orbital wall arteriovenous fistula with feeders from the left internal maxillary artery, left superficial temporal artery, and left ophthalmic artery. During the cerebral angiography, a diffuse intracranial venous anomaly and left basal ganglia arteriovenous malformations were also noted. A diagnosis of Wyburn-Mason syndrome was made, and the patient underwent catheter embolization of the orbital arteriovenous fistula. After glue embolization of the left external carotid artery feeders, the patient experienced a 50% reduction in glabellar swelling in the immediate postoperative period. Glue embolization of the left ophthalmic artery feeder was planned after six months during the follow-up period.

Multidisciplinary Management of Primary Sacral Tumors: A Tertiary Care Center's Experience and Literature Review.

Sacral tumors are rare and can be benign or malignant. Their management is multifactorial and is based on the pathology, extent, and local and distant spread. Managing sacral tumors is challenging due to their proximity to visceral and neural structures. Surgical wide excision has been the standard of care for aggressive benign and malignant tumors. Our purpose was to evaluate the outcomes of a multimodal approach to managing primary sacral tumors in Sakra World Hospital, a tertiary spine care center in Bengaluru, India and perform a literature review to determine a workflow pathway. Our study was a retrospective review of patient records and included 15 patients with primary sacral tumors. Eleven surgically treated patients were evaluated clinically and radiologically and underwent biopsy before surgical excision by an all-posterior approach. A multidisciplinary approach that included intraoperative neural monitoring, plastic reconstruction, adjuvant chemotherapy, and radiotherapy was implemented whenever necessary. Sacral root preservation was attempted whenever feasible. Functional outcomes (based on the Visual Analog Scale [VAS] and Biagini scoring system) were analyzed along with disease control, with a minimum of 2 years of follow-up. The mean follow-up was 29±9.8 months. The mean VAS score significantly improved from 7.8±2.6 to 3.7±3.8 (p =0.026). Bowel function showed statistically significant improvement, from a mean score of 0.81±0.47 to 0.63±0.52 (p =0.026) at 2 years of follow-up. The mean pretreatment motor and bladder function scores were 0.53±0.31 and 0.74±0.44, respectively, improving to 0.48±0.33 and 0.68±0.56 at follow-up but without statistical significance. There was no significant loss of function, which is expected in radical sacral resections. In conclusion, primary sacral tumors require a multidisciplinary approach and management for optimal outcomes. A stand-alone posterior approach can be employed to treat most sacral lesions. En-bloc wide resection is the optimal treatment for primary malignant and aggressive benign tumors. Preservation of at least one functional S2 nerve root is imperative to preserve bowel and bladder function.

Customized and Cost-Effective 3D Printed Mold for Cranioplasty: India's First Single Center Experience.

CONTEXT: Autologous bone is the most commonly used flap in cranioplasty to repair the defect; however, synthetic materials are available. Poly methyl methacrylate (PMMA) is an effective polymer owing to its thermoplastic and radiolucent properties comparable to bone strength. Three-dimensional (3D) printing combined with computer-assisted design (CAD) is a simple, low-cost method to print molds that ensure surgical success. MATERIALS AND METHODS: A total of 114 patients underwent cranioplasty (July 2015-April 2018), and 25 of them using 3D printed template molds due to unavailability of autologous bone. The clinical features, patient demographics, and surgical parameters were analyzed. The visual analog score for cosmesis (VASC) and Odom's score was obtained pre and post-op. RESULTS: The mean age of the patients is 38.4 ± 14.6 years (Range, 9-66). The primary pathology for undergoing craniectomy is stroke (n = 13; 52%), traumatic brain injury (10; 40%) and tumor (2; 8%). The reason for nonavailability of flap was infection (n = 14;56%), flap resorption (4;16%), and trauma or tumor (7;28%). The mean time for manufacturing the 3D printed template is 13.2 ± 2.1 h. On follow-up, median Odom's score is excellent in 52% of cases, good in 40%, and fair in 8%. The mean VASC score on follow up is 8.2 ± 1.3. Three patients developed minor postoperative complications. CONCLUSION: This is the first study from a single tertiary care center in India to systematically evaluate the outcomes in 3D cranioplasty using CAD and 3D printing technology. This method would be optimal especially in developing countries since PMMA is cost effective and also gives an ideal cosmetic effect.

Unstable Hangman Fracture Complicated by Vertebral-Venous Fistula: Surgical Considerations and Review of Literature.

BACKGROUND: Hangman fracture or traumatic spondylolisthesis of the axis associated with a traumatic vertebral venous fistula (VVF) is a rare entity and sparsely reported in literature. Standard recommendations for management of such rare and complex scenarios are not available and hence the strategy has to be individualized on a case-by-case basis. METHODS: We report a 70-year-old man having an unstable hangman fracture with VVF. Both pathologies were simultaneously managed uniquely. The VVF was managed by endovascular occlusion. The fracture was managed by anterior fusion alone as posterior fusion was deemed riskier in the aftermath of a recently occluded VVF. The patient had good neck function and bony fusion at 1-year follow-up. CONCLUSION: This case report emphasizes the need for timely recognition and management of a VVF, which can rarely coexist with hangman fracture, and discusses the interesting surgical paradigms in the management. We also present a review of literature.

Multimodal Intraoperative Neurophysiological Monitoring in Spine Surgeries: The Experience at a Spine Centre through Years.

STUDY DESIGN: Retrospective observational study. PURPOSE: To share our experience of multimodal intraoperative neurophysiological monitoring (IONM) used in Sakra World Hospital, Bengaluru in various spine surgeries. OVERVIEW OF LITERATURE: The development of new onset postoperative neurological deficits can be completely avoided. In order to avoid these, IONM has become a standard of care in recent times for early detection and manipulation of the surgical procedure to prevent postoperative neurological deficits. METHODS: This retrospective study was performed on 408 patients who had undergone spine surgeries with IONM during April 2014 to March 2020 at a single center. The operative report, anesthesia record, and IONM were reviewed. All the patients were reassessed for postoperative neurological deficits in the postoperative period and followed up based on the intraoperative findings and neurological deficits for 4 weeks. Signal changes in IONM were reviewed, and the obtained results were further categorized into true positive, true negative, false positive, or false negative. If changes were observed during the IONM, the patients were managed as per the algorithm. RESULTS: Of the 408 patients being monitored continuously during the intraoperative period, 38 showed changes in recordings, 28 developed postoperative neurological deficits, and one developed neurological deficit without any change in the IONM. Nine patients had transient neurological deficits, and the other 20 had permanent neurological deficits. Overall, the multimodal IONM used in our study had a sensitivity of 96.6%, specificity of 97.4%, a positive predictive value of 73.7%, and a negative predictive value of 99.7%. CONCLUSIONS: Use of decision algorithm and multimodal neuromonitoring consisting of motor evoked potentials, somatosensory evoked potentials, and electromyography complement each other in the detection of neurological injury during the course the surgery, improve intraoperative care, and prevent further damage and morbidity in patients.

Is Transoral Surgery Still a Relevant Procedure in Atlantoaxial Instability?

BACKGROUND: The treatment of atlantoaxial instability (AAI) involves stable fixation and fusion with adequate decompression of spinal cord. After the advent of the Goel posterior joint manipulation technique, most of the once irreducible atlantoaxial dislocations (AAD) could be reduced and the need for transoral odontoidectomy became almost nil. Here we tried to iterate the indications of anterior transoral odontoid surgery for AAI in the current scenario. METHODS: A retrospective study compiling the clinical, radiological, and surgical characteristics of 6 cases (5 scenarios). These patients underwent anterior transoral surgery alone or in combination with a posterior approach. RESULTS: Two patients had a well-formed occipito-cervical fusion mass, with a displaced odontoid and unreduced C1-C2 joint causing cervical myelopathy. A middle-aged woman presented with unreduced AAD following failed C1-C2 joint distraction technique. A displaced dystopic os odontoideum ossicle was found in an adolescent boy, prohibiting the reduction of AAD. A young man had displacement of the fractured odontoid segment with intact transverse alar ligament and C1-C2 joint complex. One patient had a rare scenario of abnormal orientation of the C1-C2 joint. All 6 patients were successfully treated with adequate spinal cord decompression achieved by the anterior transoral route and stabilization by either the anterior approach itself or in combination with posterior surgery. All had significantly better postoperative outcomes except for 1 patient who expired due to poor respiratory reserve. CONCLUSION: We tried to emphasize the indications for using transoral anterior odontoid surgery over the posterior approach in the management of AAI. This will prevent the surgical technique of anterior odontoidectomy from becoming an obsolete procedure in the current practice.

Rosette-Forming Glioneuronal Tumor in Opticochiasmatic Region-Novel Entity in New Location.

BACKGROUND: Rosette-forming glioneuronal tumour [RGNT] is a relatively rare entity first identified as a separate entity in 2002. We are reporting the second case of RGNT in the opticochiasmatic region. CASE DESCRIPTION: We report a case report and literature review of RGNT with syndromic association. CONCLUSIONS: Although initial reports were predominantly in the fourth ventricle, many recent reports have identified the possibility of its occurrence outside fourth ventricle in pineal gland, spinal cord, septum pellucidum, lateral ventricle, and suprasellar region. To date, only 1 case of RGNT involving the opticochiasmatic region has been reported in a patient with neurofibromatosis type 1. Genetic analysis of this rare tumor identified 3 hotspots involving somatic mutations of FGFR-1 and PIK3CA and a germline mutation involving PTPN11, which can be targets for therapeutic intervention in cases where complete resection is not possible. To the best of our knowledge, we report the first case of RGNT involving the opticochiasmatic region without any syndromic association. Other cases of RGNT with syndromic associations provide us with insight into possible therapeutic interventions.

Preoperative Cytoreduction of Clival Giant Cell Tumor: An Effective Replication of the Systemic Modality in the Skull Base.

BACKGROUND: Giant cell tumors (GCTs) are benign tumors with a predilection for the epimetaphyseal region of the long bones. GCTs involving the skull base are rare, and only a few available cases have been reported. Surgical gross total resection is the recommended method of treatment for GCTs. In the case of skull base tumors, it is very difficult to achieve such a result by direct surgical resection alone without any morbidities. Denosumab is a fully humanized monoclonal anti-receptor activator of nuclear factor-κB ligand antibody that has been recently approved by the Food and Drug Administration for the treatment of GCTs that are surgically unresectable, metastatic, and have a high risk of progression and recurrence. Denosumab has been used in many cases involving the long bones. However, in cases of skull base GCTs, only a limited number of cases have been reported. In addition, in such cases, it was used as postoperative chemotherapy owing to subtotal resection. CASE DESCRIPTION: For the present patient, we adopted a unique approach in which denosumab was administered as neoadjuvant chemotherapy to reduce the size of the tumor to a resectable level. Subsequently, surgical resection was performed with good functional and histopathological outcomes. CONCLUSIONS: Our findings emphasize the use of denosumab as a neoadjuvant treatment routinely for all cases of skull base GCTs to achieve safe and complete excision of the tumor.

Lumbar pseudomeningocele presenting as decerebrate rigidity-A rare case entity.

INTRODUCTION: Spinal pseudomeningoceles are extradural collections of cerebrospinal fluid that result following a breach in the dural-arachnoid layer and is reported as one of the complications of lumbar disc surgery. Although they are often self subsiding and asymptomatic, they may occasionally cause low-back pain, headaches, and even nerve root entrapment. The purpose of this case report is to present an unreported presentation of pseudomeningocele PRESENTATION OF CASE: A 34 year obese male presented one month post lumbar discectomy with symptoms suggestive of raised intra cranial pressure presenting as repetitive decerebrate rigidity and altered sensorium lasting for few minutes when there is pressure on the pseudomeningocele sac and subsiding with change in position of the patient. He underwent surgical repair of the dural tear and was improved symptomatically with no recurrence of symptoms at five years follow up. DISCUSSION: Radiological investigation helped in ruling out the other causes of decerebrate rigidity and the possible mechanism of development of such symptom in pseudomeningocele is discussed. CONCLUSION: To the best of our knowledge, this is the first reported case of pseudomeningooele presenting as decerebrate rigidity. Spinal pseudomeningocele can present in varied ways and earliest detection is the key to avoid such complications.