Ashis Pathak

Tuberculosis of the craniovertebral junction: is surgery necessary?

OBJECTIVE:Tuberculosis of the craniovertebral junction is an uncommon entity and its optimal management remains controversial. In this study, we present the evolution of management protocol of this disease in our institute in the past 3 decades. METHODS:A total of 51 patients with craniovertebral junction tuberculosis presenting as atlantoaxial dislocation from 1978 through 2004 were reviewed. The disease was rated from Stage I to Stage III, depending on the radiological findings. All patients received antitubercular treatment for 18 months. In the initial period of this study (1978–1986), all patients (n = 10) underwent surgery, usually a posterior fusion. In the second period (1987–1998), patients with less severe disease (Stages I and II, n = 14) were managed with external rigid immobilization, whereas patients with severe disease (Stage III, n = 11) underwent either a transoral decompression with or without posterior fusion or posterior fusion alone. More recently (1999–2004), all patients (n = 16) in all stages (Stages I–III) have been managed without surgery by a rigid external immobilization. RESULTS:Except for two patients who died (one because of miliary tuberculosis, the other because of acute hydrocephalus), clinical recovery occurred in all. Follow-up imaging demonstrated radiological healing as well, with regrowth of the destroyed bone. CONCLUSION:The mainstay of management of tuberculosis of the craniovertebral junction is prolonged antitubercular treatment with a rigid external immobilization. Surgery is not necessary, even in patients with advanced stages of disease. Complete clinical and radiological healing occurs in all patients with conservative treatment.

Neuroprotective effect of progesterone on acute phase changes induced by partial global cerebral ischaemia in mice

The possible neuroprotective effect of progesterone, a steroid hormone, on acute phase changes in a mouse model of cerebral ischaemia induced by bilateral common carotid artery occlusion (BCAO) was studied. A total of 72 male mice were included in the study. The BCAO model was used to induce partial global cerebral ischaemia. Morphological assessment included measurement of infarct size and brain oedema. Post‐ischaemic seizure susceptibility was assessed using a subconvulsive dose of pentylenetetrazole (30 mgkg−1 i.p.). Biochemical estimations included tumour necrosis factor α (TNF‐α) levels and enzyme parameters such as lipid peroxidation, superoxide dismutase, catalase and glutathione peroxidase, and protein estimation. BCAO induced a significant infarct size and oedema in the saline‐treated control group, along with an increase in oxidative stress, indicated by increased lipid peroxidation and decreased levels of antioxidants such as superoxide dismutase, catalase and glutathione peroxidase. Progesterone (15 mgkg−1 i.p.) administration showed a neuroprotective effect by significantly reducing the cerebral infarct size as compared with the control group. Post‐ischaemic seizure susceptibility was also reduced as the number of positive responders decreased. Brain oedema subsided, but not significantly. Progesterone significantly reduced TNF‐α levels compared with the ischaemia group. Progesterone improved levels of all the anti‐oxidants, indicating activity against oxidative stress induced by BCAO. The results demonstrate the neuroprotective effect of progesterone against ischaemic insult, suggesting a role for the steroid as a neuroprotective agent.

Tension pneumocephalus following evacuation of chronic subdural haematoma.

Five cases of a rare complication of tension pneumocephalus following evacuation of chronic subdural haematoma are described. This occurred in 8% of all cases of chronic subdural haematoma treated following installation of a CT scanner. The chronically compressed brain contributes to the ingress of this intracranial air. The increase in the brain bulk and gradual re-expansion of the brain, in the early postoperative period, competes with the trapped subdural air resulting in a rise in intracranial pressure leading to neurological deterioration. Twist drill craniostomy and aspiration, using a brain cannula with a three-way connector, has produced excellent results.

Relationship between severity of traumatic brain injury (TBI) and extent of auditory dysfunction

Objective: To find out the relationship between severity of traumatic brain injury (TBI) and extent of auditory dysfunction Background: Most of the studies have taken the subjects with TBI as one group without taking into account the extent of head injury viz. mild, moderate and severe. Combining all the three groups has resulted in presenting an incomplete picture of auditory deficits following TBI. Methods and procedures: The sample population consisted of 290 subjects with TBI (study group) and 50 otologically normal subjects as controls. The subjects in the study group were further sub-divided into mild (n = 150), moderate (n = 100) and severe (n = 40) TBI. The audiological assessment consisted of pure tone audiometry, speech audiometry, tympanometry, acoustic reflex testing, auditory brainstem response and middle latency response audiometry. Results and conclusions: An association was observed between the extent of auditory dysfunction and severity of TBI. This association was more pronounced for hearing status at high frequencies and ABR/MLR components. ABR Wave V absolute latency and I–V interpeak latency increased with severity of TBI. Amplitude of MLR wave Na and Pa decreased with increasing severity. It is suggested that subjects should be evaluated for hearing difficulties based on their severity of TBI.

Audiological deficits after closed head injury.

BACKGROUND Damage to the peripheral auditory structures has long been recognized as a common component of head injury. It is estimated that a majority of patients with skull trauma have resultant hearing impairment. Damage to the peripheral and/or central auditory pathways can occur as a primary or secondary injury. Considering the high incidence of hearing loss, it was considered worthwhile to conduct an in-depth investigation by administering a comprehensive audiological test battery on head-injured patients. METHOD The sample population consisted of 290 subjects with closed head injury (study group) and 50 subjects with otologically normal subjects (control group). The subjects in the study group were further divided into mild (n = 150), moderate (n = 100), and severe (n = 40) category on the basis of Glasgow Coma Scale score. The audiological assessment consisted of pure tone audiometry, speech audiometry, tympanometry, acoustic reflex testing, auditory brain stem response audiometry, and middle latency response audiometry. RESULTS AND CONCLUSIONS It is concluded that there is higher prevalence of hearing impairment in the study group compared with control group. Majority of the patients who incur hearing loss after closed head injury have mild degree of hearing impairment. A significant difference between the study and control group observed on majority of the auditory brain stem response and middle latency response parameters studied.

Infected Intraparenchymal Dermoids: An Underestimated Entity

Infection secondary to a dermal sinus most commonly occurs in the form of cutaneous, epidural, or subdural abscesses. Rarely, it can result in an intramedullary abscess as a result of a dermal sinus. This study presents a clinicoradiological profile of 19 cases harboring abscesses within the dermoids and highlights the importance of dermal sinus acting as a pathway for infections to enter the nervous system. Emergent exploration, pus drainage, and minimal abscess wall excision along with prolonged antibiotic administration remained the management of choice in all cases. Methicillin-sensitive Staphylococcus aureus was the commonest offending organism. In all, 7 patients recovered to normal neurological status, 5 showed no improvement, and 7 improved partially. Improvement in motor power was noted, albeit partially, but bladder functions failed to recover even at long-term follow-up. Even when such infective complications of dermal sinuses are rare, these are potentially serious and disabling.

Long-term outcome in surviving patients after clipping of intracranial aneurysms.

OBJECTIVE The quality of life and functional outcome may be significantly impaired in patients of aneurysmal subarachnoid hemorrhage. The purpose of the present study was to assess the status of patients undergoing surgical clipping of intracranial aneurysms in a long-term follow-up and to identify factors affecting outcome. METHODS 494 patients who underwent clipping of their intracranial aneurysms with a minimum follow-up of 1 year after their discharge were studied. Preoperative factors such as age, Hunt and Hess grade, Fisher grade, time interval between ictus and surgery, and site of aneurysm were recorded. The long-term status was assessed using Glasgow Outcome Scale (GOS), Modified Rankin Scale (MRS), Barthel index (BI), and Mini-Mental State Examination (MMSE). RESULTS Site of aneurysm and ictus-surgery interval did not have any effect on any parameter at long-term follow-up. Majority of patients who were discharged continued to improve as measured by GOS, Modified Rankin Scale, and Barthel index. However a significant proportion of patients had impaired MMSE at long-term follow-up. Multivariate analysis showed a significant effect of age on MMSE and also a positive correlation between number of aneurysms and GOS. CONCLUSIONS Most patients who survived and were discharged continued to improve in the postoperative period even though the immediate postoperative outcome was not favorable in many. However, a substantial subset had impaired cognitive function.

Dynamics of Hearing Status in Closed Head Injury

Hearing impairment can be one of the more subtle deficits seen after closed head injury (CHI), and it may not be diagnosed until late in the recovery phase if at all. Most studies have assessed patients immediately after CHI. Repeated assessments at regular intervals were not performed in the majority of studies done to assess whether any initial hearing loss regressed or progressed. Follow-up at later stages will shed more light on the audiological consequences of CHI. The aim of this study was to analyze the long-term audiological consequences of CHI. A total of 290 subjects with CHI were chosen and followed-up at 3, 6, and 12 months. The audiological test battery comprised pure tone audiometry (PTA), speech audiometry, tympanometry, auditory brainstem response (ABR), and middle latency response (MLR), and was administered to all subjects. The data from 96 subjects who completed all three follow-ups were analyzed for tympanometry, ABR, and MLR. However, for PTA and speech audiometry, data from only 76 subjects were analyzed, as unconscious and disoriented subjects could not undergo these tests at initial testing. The results revealed that hearing status after CHI varies, and that at follow-up significant changes in hearing were seen. Hearing of low frequencies improved, due primarily to improvements in middle ear function. Significant changes in ABR latencies and MLR amplitudes were also observed. This reflects the unequal rates of recovery observed in the different parts of the central auditory nervous system.

Ruptured posterior cerebral artery aneurysm in association with neurofibromatosis type 2--a case report.

Intracranial aneurysms have been described in patients with Neurofibromatosis (NF)- 1, but not with NF-2 apart from one instance of a middle meningeal artery aneurysm (Louis DN, Ramesh V, Gusella JF. Neuropathology and molecular genetics of neurofibromatosis 2 and related tumors.1 We report a case of NF-2 and ruptured posterior cerebral artery aneurysm.

Post head injury vertigo

Abstract Post Head Injury Vertigo (PHIV) is a common symptom after head trauma and is a part of post-concussion syndrome. The causes of vertigo can be varied. A study was aimed to: (a) Clinically classify pure PHIV into various groups depending on the severity of disability produced by the vertigo and, (b) To evolve a treatment protocol for PHIV. A new classification of PHIV was proposed, based on its severity, ranging from Grade I to Grade IV, Grade IA being of least severe manifestation. A total of 53 patients of mild head injury having PHIV were analysed, consisting of 32 males and 21 females with age ranging between 18 and 62. Eight patients of PHIV fell in Grade IA, 10 in Grade IB, 26 in Grade II, 8 in Grade III and 1 was in Grade IV. The mean number of hospital visits increased with the severity of vertigo with Grade IA having a mean of 1.5 visits and Grade IV having a mean of 24 visits. Though the dosage of medication and its duration was not always proportional to the grade of vertigo but Grade III and IV patients needed prolonged medications, sometimes with more than one drug. The higher grades of PHIV were supplemented with vestibular rehabilitation exercises. In conclusion, the present study is the first one of its kind attempting to classify PHIV into various grades depending on its severity. The grading system can help the clinician to plan the approximate duration of treatment and also prognosticate PHIV.