ABSTRACT

CORRESPONDING AUTHOR:
Dr. Ramachandra Rama Mohan Naik,
Assistant Professor,
Department of Neuro Surgery,
Osmania Hospital, Afjalgunj,
Hyderabad – 500024, Telangana.
E-mail: rammohan_naik@yahoo.co.in

ABSTRACT: BACKGROUND: Cerebral abscess is a serious life threatening complication of several diseases like CSOM congenital heart disease and trauma. Aspirations of abscess cavity verses excision of capsute are still in debate for the capsulated large abscess. Repeated aspirations is a good alternative for the patient who are not fit for surgical excision and deep seated abscess which are located in eloquent areas. The objective of this study is to look for the clinical presentation etiological factors and outcome of patients with repeated aspiration is brain abscess. METHODS: The prospective study was conducted in department of Neurosurgery, Osmania General Hospital, Hyderabad from June 2009 to June 2012, 24 patients; age ranges from 2 to 70 years. After through clinical examinations and work up patients were subjected to operate procedure. The procedure includes aspiration of brain abscess with single burr hole, followed repeat CT scan then repeated aspiration if required, under anti-biotic cover. Data regarding age and sex distribution, site of abscess, clinical presentation, outcome of patients after threatened with repeated aspiration were analyzed. RESULTS: First and second decade is commonly affected age consist of 50% of cases, males are commonly affected 83% and 16.6% were females cerebellum is the commonly affected 29.2% (7) less common is occipital lobe 4%,⁽¹⁾ CSOM is commonest predisposing factor 10 patients (41.6%) followed by congenital heart diseases 5 (20%). Fever and headache is commonest presentation 54.2% and 45.8%. CONCLUSION: Brain abscess resulting from CSOM is the common cause, Males are most commonly affected, commonest site of brain abscess is cerebellar followed by parietal lobe, Plain CT scan brain with contrast is the main investigation of choice in diagnosis of brain abscess. Repeated aspirations is safe and with less mobility and mortality. when the size of abscess remains same after repeat aspiration may need excision.

KEYWORDS: Brain abscess. Repeated aspitations.

INTRODUCTION: Pyogenic brain abscess is one of the common neurological emergencies. Brain abscess is an intra-parenchymal collection of pus. In India Brain abscess accounts for about 8% of intracranial mass lesions. Where as in west it is only 1-2%,^1-3 Incidence depends on geographical locations and living standard of people. Brain abscess usually results due to direct spread from contagious. Infective focus from para nasal sinuses, or middle ear, or due to trauma, and hematogenous spread through cerebral circulations and by direct introduction into brain after trauma surgery.^{(4, 5)} Hematogenous abscess occurs in the distribution of middle cerebral artery. The formation of brain abscess progress through several well defined stages from early cerebritis to late capsule formation.

The basic principle of treatment are

1. Control of infection by appropriate systemic antibiotics.

2. Surgical management of brain abscess by aspiration or excision

3. Eradication of primary focus and

4. Treatment of sequelae seizures, weakness, or hydrocephalus

                Treatment options may vary from only antibiotics to surgical excision of abscess, currently abscess more than 2.5 cm are being treated with surgical aspirations with antibiotics for 6-8 weeks.

                The present study is carried out to study the age incident clinical presentation and outcome of repeated aspiration with monitoring of abscess with C.T scan brain.

MATERIALS AND METHODS: This prospective study on 24 brain abscess patients conducted in Department of Neurosurgery Osmania general hospital, Hyderabad, India. Study period extend from June 2009 to June 2012.

                This is a detailed study regarding the age of presentation, clinical signs and symptoms. Through clinical examination of the patients were performed to evaluate the source of infection. The diagnosis was conformed with C.T scan brain plain and contrast after necessary hematological evaluation. The patients were subjected to the operative procedure after taking contrast about the procedure and the data for research.

                The procedure include the single burr hole aspiration for the supra tentorial as well as infra tentorial abscess. The results of surgery were evaluated with repeat C.T scan of brain plain with contrast after 24 hours. The procedure is repeated for the residual abscess. The antibiotics were given according to culture and sensitivity report for 2 weeks intravenously and orally for next 4 weeks.

Anti-convulsions were given prophylactics for the all the patients and continue for 3 months.

RESULTS: Among 23 patients 83% were males and 16.6% were females, 2^nd decade is most commonly affected consist of 50% of cases. The predisposing factors found were, CSOM in 10 (41.6%). Congenital heart diseases 5 (4.2%) post traumatic -4 (16.6%) and post-operative 1 (4.2%).

Fever was the predominant presenting complaint in 13 (54.2%) followed by headache 11 (45.8%) altered sensorium 9 (37.5%) hemiparesis 8 (33.3%), nystagmus in 4 (16.6%). On C.T scan cerebellum is the common site involved 7(29.2%) followed by parietal 6 (25%) frontal (12.5%) and temporal 3 (12.5%).

Staphyloccus is the common organisms in aspirated pus on culture, 4 (16.5%) no organisms seen in 13 (54%). May be due to usage of pre-operative antibiotics.

All the patients were initially managed with burr hole aspiration, 58.3% cases required repeated aspiration, 41.7% cases were responds single aspiration, 16.6% cases which were not cured by aspiration, craniotomy and excision of abscess was done.

                First and second decade is most commonly affected by brain abscess consists of about 50% of cases. Youngest patient in our series is 1 ½ years and eldest is 70 years. 83% were males and 16.6% were females.

SITE OF ABSCESS:

                Cerebellum is the commonest site affected followed by parietal lobe. Occipital lobe is less commonly affected.

ETIOLOGY:

CLINICAL PRESENTATION:

                Fever, headache and mental status changes are the most common presenting symptoms with brain abscess.

ORGNISMS CULTURED FROM ASPIRATED PUS

                Brain abscess was diagnosed by CT scan brain on admission. CT scan brain showed ring enhancing lesions with peripheral edema.

                In cerebellar abscess certain showed hydrocephalus due to compression on the fourth ventricle.

                In case of doubtful diagnosis magnetic resonance image with spectroscopy is needed to certain the diagnosis.

                Blood investigations like total count, differential count and ESR were performed for all the cases. It does not help much in diagnosing the brain abscess.

                Repeat CT scans were performed almost weekly or more frequently if the new symptom develops or if there is no improvement of the patient after the aspiration to assess the size of the abscess.

DISCUSSION: AGE & SEX DISTRIBUTION: Most common age group affected is:

1 – 20 years i.e; about 50% of cases in our series.

81.8% in U.S. Srinivasan and Joseph et al series.

36.5% in Yamamoto et al series.

Males are most commonly affected in all the series.

                Most of the patients in our series were treated by aspiration (20, 83%) and had a favorable outcome. Most patients were treated with antibiotics, cefotaxime, gentamycin & metronidazole while awaiting the bacteriological results and the regimens were promptly changed accordingly to the results of culture and resulting testing. In most of the cases the culture is sterile in out series probably due to use of antibiotics prior to coming to the hospital.

                Bacterial brain abscess often require repeated aspirations before the abscess finally resolves. Most series found that two or three aspiration procedures were generally sufficient. In our series about 14 patients require more than one aspiration. The criteria for repeat aspiration are when the size of and main effect of the abscess were not decreased on repeated CT scan after the first operation.

The repeated CT scan was done after one week of the initial surgical aspiration or before one 1 week when the patient consciousness level deteriorates or new symptoms develops.

The size of the abscess is an important factor when planning initial therapy. Large abscess may be refractory to antibiotic treatment alone. Medical treatment has been successful with abscess smaller than 2.5 cms in diameter.

However, there are no strict guidelines for treatment by aspiration is unclear. The abscess should be repeatedly aspirated when the size is not changed or has enlarged from the initial postoperative CT scan.

In our series abscess could be successfully treated by antibiotics alone without for further aspiration after the diameter was reduced less than 2.5 cms.

                If the size of the abscess is not coming down after the 2 to 3 aspirations we advocate excision of the abscess. Important criteria for excision after 2 aspirations are if the size of abscess remains same after the 2 aspirations.

CONCLUSIONS: Brain abscess is life threatening neurological emergency, which requires aggressive treatment. CT scan brain plain with contrast is the investigation of choice in diagnosing the brain abscess and to exclude the other etiology. Rarely MRI brain with MR spectroscopy needed to differentiate from other causes.

                Tetralogy of Fallot’s is the commonest congenital heart disease leads to solitary cerebral abscess. Majority of the abscess can be managed with repeated aspiration with less mortality and morbidity.

                The size of the abscess is an important factor when planning the initial treatment and the size of the abscess should be closely monitored after the aspiration with C.T scan.

                When the size of the abscess remains same with thick capsule it needs excision.

BRAIN ABSCESS MRI

LEFT FRONTAL ABSCESS ON CT

MULTIPLE BRAIN ABSCESS IN A CHILD

BIBLIOGRAPHY:
1.    Srinivasan U.S, Gajendran. R., Joseph M.J. Pyogenic brain abscess managed by repeated elective aspiration-, Neurology India 1999;47:202.
2.    Bhatia R, Tandon PN, Benerji AK: Brain abscess- an analysis of 55 cases. Int surg 1973; 58: 565 – 568.
3.    Current concepts in the management of Pyogenic brain abscess, B.S.Sharma, Gupta S.K, Khosla V.K, Neurology India 2000; 48: 105.
4.    Management of brain abscess – current concepts – SR Dharker, VR Sardana and D Purohit. Progress in clinical neuroscineces –XVII: 98 – 105.
5.    Dharker Sr, Shndangi Viashya ND, Arora V.K, - Pyogenic brain abscess – experience with 87 cases, neurology India 26:126-130, 1978.
6.    Treatment of bacterial brain abscess by repeated aspiration – follow up of serial CT scan-M.Yamamoto, Takeo, Fukushima – Neurology. Med. Chir (Tokyo) 40, 98 – 105; 2000.
7.    Experience with 88 conservative cases of brain abscess – Morgan MD, Mathew W, Wood MD, Journal of neurosurgery Vol. 38, June 1973, 699:703.
8.    Moorthy RK, Rajashekar V. Mangaement of of brain abscess an overview. Neurosurg Focus 2008; 28(6):E3.