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Featured researches published by Tandon Pn.


Acta Neurochirurgica | 1987

Cranio-cerebral erosion (growing fracture of the skull in children). Part II. Clinical and radiological observations.

Tandon Pn; Aleena Banerji; R. Bhatia; R. K. Goulatia

SummaryThis paper is based on a study of sixty cases of cranio-cerebral erosion treated in the Department of Neurosurgery. All India Institute of Medical Sciences, New Delhi during the last 20 years. This constitutes the largest series, so far reported from anywhere. It has provided a unique opportunity to get a comprehensive picture of the clinical and radiological features of this lesion, as also their evolution. These have been correlated with the findings at surgery and histopathological observations. The study highlights the incidence, pattern and severity of the brain damage associated with this lesion. Evidence has been provided for the progressive nature of the brain damage, not adequately emphasized in the existing literature. Pathogenesis of this brain damage has been discussed. The role of surgery in the management of this lesion has been outlined. Emphasis on the osseous changes or the “leptomeningeal cyst” (not really a consistent or important feature) in most publications on this subject has tended to minimize the significance of the brain damage in this condition. The authors suggest that the latter is far more important and therefore, recommend the use of nomenclature which takes this into account.


Acta Neurochirurgica | 1987

Cranio-cerebral erosion (growing fracture of the skull in children)

Soumyajit Roy; Chitra Sarkar; Tandon Pn; Aleena Banerji

SummarySeventeen cases of cranio-cerebral erosion were subjected to detailed histopathological study in order to get a better insight into the pathogenesis of this lesion. It was found that the bone and brain at the site and edge of the defect show not only evidence of damage at the time of initial injury, but also of “active” progressive damage months and years later. The possible causes for continuing damage to the brain and bone are discussed.


Cancer | 1988

Oligodendroglial tumors: an immunohistochemical and electron microscopic study

Chitra Sarkar; Subimal Roy; Tandon Pn

Fifty‐five cases of oligodendrogliomas and mixed oligoastrocytomas were evaluated using immunohistochemical (IH) study for glial fibrillary acidic protein (GFAP) and electron microscopic (EM) study. Most of the tumors in both of these groups showed many neoplastic oligodendroglial cells with GFAP‐positive staining in their cytoplasm by IH study. By EM study too, many tumor cells showing features of oligodendroglial cells contained intermediate filaments. Our observations suggested the presence of a transitional form of cells in these tumors. The current study supports the contention that both oligodendrogliomas and oligoastrocytomas arise from a common progenitor cell capable of differentiation into both oligodendrocyte and astrocyte. The nature and degree of differentiation depends probably on gene expression and/or some microenvironmental factors.


Acta Neuropathologica | 1972

Chondrosarcoma of the meninges

Subimal Roy; P. K. Chopra; Brahm Prakash; Tandon Pn

SummaryA case of chondrosarcoma of the meninges in a 32 year old male is reported.


Pathology & Oncology Research | 2000

A comparative survival evaluation and assessment of interclassification concordance in adult supratentorial astrocytic tumors

Asis Kumar Karak; Rajvir Singh; Tandon Pn; Chitra Sarkar

Classification and grading of astrocytic tumors has been the subject of several controversies and no universally accepted classification system is yet available. Nevertheless, acceptance of a common system is important for assessing prognosis as well as easy comparative evaluation and interpretation of the results of multi-center therapeutic trials. We report the results of a single center study on comparative survival evaluation along with assessment of interclassification concordance in 102 cases of supratentorial astrocytic tumors in adults (≥ 16 years of age). Hematoxylin and eosin (H&E) stained slides of these 102 cases were reviewed independently by two pathologists and each case classified or graded according to four different classification systems viz. Kernohan, Daumas-Duport (SAM-A), TESTAST-268 and WHO. The histological grading was then correlated with the survival curves as estimated by the Kaplan-Meier method. The most important observation was that similar survival curves were obtained for any one grade of tumor by all the four classification systems. Fifty three of the 102 cases (51.9%) showed absolute grading concordance using all 4 classifications with maximum concordant cases belonging to grades 2 and 4. Intra-classification grade-wise survival analysis revealed a statistically significant difference between grade 2 and grades 3 or 4, but no difference between grades 3 and 4 in any of the classification systems. It is apparent from the results of this study that if specified criteria related to any of the classification systems is rigorously adhered to, it will produce comparable results. Hence, preferential adoption of any one classification system in practice will be guided by the relative ease of histologic feature value evaluation with maximum possible objectivity and reproducibility. We recommend the Daumas-Duport (SAM-A) system since it appears to be the simplest, most objectivized for practical application and highly reproducible with relative ease.


Acta Neurochirurgica | 1978

Temporal lobe lesions in head injury

Tandon Pn; B. Prakash; Aleena Banerji

SummaryIn cases of closed head injury temporal lobe lesionse.g. contusion, laceration, pulping, or intracerebral haematoma frequently result in an expanding process. These are frequently associated with an overlying subdural haematoma. Eighty five cases of such lesions from a consecutive series of 1,000 cases of head injury have been analyzed. The lesions are caused by severe injury resulting in loss of concsiousness and skull fracture. Most of them are contre-coup lesions. Clinically they manifest themselves like any other acute or subacute intracranial hematoma. The majority of the patients have contralateral hemiparesis and pupillary abnormalities. Carotid angiography is valuable for diagnosis. These lesions are likely to be missed when exploratory burr holes are made or, are erroneously diagnosed as acute subdural haematoma or brain oedema. Smaller lesions, not showing progressive deterioration, may respond to conservative treatment. However, surgical decompression is essential in most cases. A fronto-temporal osteoplastic craniotomy or a large Scoville trephine hole is essential to deal with these lesions adequately.


Neurology India | 2009

Transplantation and stem cell research in neurosciences: Where does India stand?

Tandon Pn

The nearly absent ability of the neurons to regenerate or multiply has prompted neuroscientists to search for the mean to replace damaged or dead cells. The failed attempts using adult tissue, initiated nearly a century ago, ultimately brought rays of hope when developing fetal neurons were used for transplantation in 1970s. The initial excitement was tempered by limited success and ethical issues. But these efforts unequivocally established the feasibility of successful neural transplantation provided appropriate tissue was available. The ability to derive embryonic stem cells with their totipotent potential by Thomson in 1998 rekindled the interest in their use for replacement therapy for damaged brain tissue. The present review surveys the current status of this promising field of stem cell research especially in respect to their therapeutic potentials for purposes of neural transplantation. A brief account is provided of the ongoing Indian efforts in this direction.


Acta Neurochirurgica | 1987

Brainstem auditory evoked response and vestibulo-ocular reflex in severe head injury patients A prospective study of 60 cases

Ashok Kumar Mahapatra; Tandon Pn

SummaryBrainstem auditory evoked response (BAER) performed in 60 serious head injury patients, over the last two year period at All India Institute of Medical Sciences, New Delhi have been analysed, to correlate the findings with ultimate outcome. All patients included in this study were unconscious, not following any command at the time of initial evaluation, mostly within 48 hours of injury. Repeat studies were performed in surviving patients. Computerized cranial tomography was performed to establish the nature of the intracranial pathology. The clinical status and cold caloric responses were recorded in all. The patients were followed up for 1 to 24 months. Three patients had extradural haematoma, 2 patients had subdural haematoma and 30 patients had intracerebral contusion/haematoma. Brain oedema was recorded in 14 cases. BAER was normal in 32 patients and 26 of them had good recovery (81%). Three patients with normal BAER died. Abnormal BAER was recorded in 21 patients and only 50% of them had good recovery and 25% of them died. In 7 patients BAER was absent and only 2 (29%) had a good recovery. Thus 48 out of 60 patients (66%) had a good recovery and 11 (18%) died. When compared to cold caloric response, 87% patients with normal caloric response had a good recovery and 5 out of 6 patients with absent caloric response died and remaining 1 left in a vegetative state. Thus the caloric response is at least as good a prognostic factor as BAER.


Surgical Neurology | 1985

Bilateral decerebration in head-injury patients: An analysis of sixty-two cases

Ashok Kumar Mahapatra; Tandon Pn; R. Bhatia; Aleena Banerji

The factors that contributed to recovery were reviewed in 62 head-injured patients with bilateral decerebration. The most important prognostic variables were age, mode of accident, time interval since injury, results of initial neurological evaluations, and the type of intracranial mass lesion. A higher survival rate was recorded in patients less than 20 years of age, those involved in nonvehicular accidents, those admitted within 6 hours of the accident, and where the vestibuloocular reflexes were preserved. Patients with extradural hematomas and those with nonsurgical intracerebral mass lesions also had a relatively better prognosis. In no patient was elective ventilation, steroid, or megadose barbiturate therapy utilized. Twenty patients (32%) of the 62 survived, and 11 patients had a good functional recovery.


Archive | 1986

‘Radical’ surgical decompression of supratentorial gliomas. Do the results justify the operation?

Tandon Pn; Satya Pal Agarwal; Ashok Kumar Mahapatra; Subimal Roy

The utility and extent of surgery for supratentorial hemispherical gliomas, remain controversial issues one hundred year after Godlee’s first operation for such lesions. The results of an unselected consecutive series of 500 patients submitted to ‘radical’ surgical decompression are presented. Number of cases affecting the dominant or the non-dominant hemisphere were nearly equal. Extent of preoperative neurological deficit or the involvement of midline or the basal ganglia was not considered a contraindication for surgery in this series. The overall mortality for the whole series, which included many advanced cases was 13.8 percent. There was no significant difference in the mortality for tumors of either hemisphere. Pre-existing dysphasia improved in 50 percent cases, while significant increase in deficit was observed in only 11.3 percent cases. Tumors crossing the midline or involving the basal ganglia had a lower survival rate but this did not preclude, satisfactory results amongst the survivors. ‘Radical’ surgical decompression as described here, is therefore recommended as a safe method of reducing the tumor burden, establishing a definitive histological diagnosis and ameliorating the devastating effects of raised intracranial pressure without significantly adding to the morbidity of these patients. As a matter of fact gratifying regression in pre-existing neurological deficit in sizeable number of cases, improved the quality of survival.

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R. Bhatia

All India Institute of Medical Sciences

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Subimal Roy

All India Institute of Medical Sciences

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Chitra Sarkar

All India Institute of Medical Sciences

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Ashok Kumar Mahapatra

All India Institute of Medical Sciences

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Brahm Prakash

All India Institute of Medical Sciences

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Narayana Kochupillai

All India Institute of Medical Sciences

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Soumyajit Roy

All India Institute of Medical Sciences

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A.K. Mahapatra

All India Institute of Medical Sciences

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Amit K. Dinda

All India Institute of Medical Sciences

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