MANAGEMENT OF OSTEOID OSTEOMA

MEDICAL MANAGEMENT:

As discussed earlier, there may be delay between onset of symptoms and initiation of diagnosis of osteoid osteoma. Initial therapy of choice in most cases is medical. Salicylic acid is often helpful to give sypmptomic and lasting relief from night pain. It has been suggested that prostaglandins play important role in the pathogenesis of osteoid osteoma as large amount of prostaglandins were found in the histologic specimen of excised lesions. This is the reason behind immediate pain relief from prostaglandin synthesis inhibitors like aspirin. If there is no relief with medical therapies, then others treatment options should be sought.

SURGICAL MANAGEMENT:

Definitive cure can only be achieved with surgical excision of the lesion. But there are hurdles in complete removal of lesion and exact localization is one of the most important hurdles. Preoperative localization can be achieved with x-rays or computerized tomography. If there is still any problem in the localization, then there are many intraoperative options available for precisely localizing the tumor.

One of such options is use of x-ray during surgery. Another method is use of scintillating needles which are easy to use and are considered the best method to localize the lesion. Precise localization means less bone excision, excellent cure with less chances of recurrence and complete removal of nidus in the excised specimen. The excised sample is then sent to the laboratory for histological examination to look for presence of nidus. If nidus is not found, second attempt is made to remove it properly.

Sometimes it is difficult to completely remove intra-articular lesions in which case, other treatment options are adopted.

RADIOFREQUENCY ABLATION:

In this method, computerized tomographic guidance is taken to insert a needle which will ablate the tumor with the help of radiofrequency waves. This method has excellent results but needs expertise of the part of surgeon.

OTHERS MANAGEMENT OPTIONS:

Computerized tomography percutaneous removal can be attempted in some cases. Sometimes deroofing and curettage is contemplated.

A new technique in this context is the introduction of magnetic resonance guided focused ultrasonography for the excision of tumor with some promising results.

OSTEIOD OSTEOMA

A commonly occurring benign bone forming tumour can occur in any age group with increased male preponderance. It was first described in 1930 and later identified as a separate disease in mid of 1930s. osteoid osteoma can involve any bone but is more commonly found in long bones and that too in tibia, femur and humurus. Involvement of spine, hand and feet is also documented.

Almost two third of all cases of osteoid osteoma occur in the long bones involving shaft, epiphyses of diaphysial region. When spine is the site, involvement is mor.e commonly seen in posterior components like spinous processes, lamina or pedicles. Facet joint involvement can also occur.

Patient presents with onset of pain in the region of affected bone. Pain is sharp and agonizing and starts more often at night. It is relieved by taking medications like disprin. Pain usually does not occur in the morning of day time. Sometimes patient may present with swelling at the site of lesion.

On examination, there may be element of tenderness at the site of tumor. There may be obvious swelling. Sometimes, although not common, there may be warmth and redness suggesting inflammatory process.

Laboratory findings are usually normal and the diagnosis is often delayed for quite some time. There have been evidences that a 3 year delay was documented from the onset of symptoms. This delay is contributed by many factors including equivocal imaging findings, complete pain relief by salicylates and sometimes complete resolution with time.

DIAGNOSING OSTEOID OSTEOMA:

X-RAY:

Imaging has evolved greatly and routine use of radiography is still considered to the first modality of choice in the diagnosis of osteoid osteoma. On x-ray, there is a lucent line in the region of tumor with surrounding rim of increased bone density or sclerosis. There is thickening of cortex. The central lucent area is called nidus and consists of highly vascular soft tissue component of the tumor. Sometimes the lesion is in the subperiosteal region and lucent line may not be appreciated. It is quite possible that only sclerotic rim is visible and no lucent nidus appreciated. If the lesion is intra-articular, then it may be possible to only appreciate minimal sclerosis around the central lucency.

Tumor usually does not extend beyond 2 cm size. If spine is involved, there are much more chances of scoliosis with concave side towards the tumor. Any young who complains of neck or back pain should be suspected of having this tumor and be investigated accordingly. Most common age of this tumor is about twenty five years.

CT SCAN IN THE DIAGNOSIS OF OSTEOID OSTEOMA:

Computational tomography is now considered best modality of choice for those lesions which are not picked on routine x-ray examination. CT helps to better localize and define the lesion. A nidus can be found easily in this modality. It also confirms the presence of surrounding sclerosis and thickening of cortex. This modality is considered best for detecting intra-articular lesions specially hip joints. With the advent of multiplaner reconstruction, it is easier to localize the tumor.

BONE SCANNING IN THE DIAGNOSIS OF OSTEOID OSTEOMA:

This modality has a hundred percent sensitivity in the diagnosis of osteoid osteoma. It can detect lesions which were missed on x-ray. It can also differentiate it from other lesions like spondylolysis by performing immediate and delayed scanning. In case of osteoma, there is tracer uptake immediately after injection, a feature which is not seen in case of spondylolysis.

MAGNETIC RESONANCE IMAGING IN THE DIAGNOSIS OF OSTEOID OSTEOMA:

MRI is not considered better option because it can miss the lesion and also there is sometimes confusion in interpretation of lesion. Features may suggest malignancy when it is not there. Nevertheless, MRI will show hypointense signals in the lesion on T1W imaging with post-contrast enhancement which may be uniform of ring like.

CLICK HERE FOR MANAGEMENT OF OSTEOID OSTEOMA:

TUBERCULOSIS

TUBERCULOSIS

Tuberculosis is a chronic granulomatous inflammatory process caused by anerobic acid fast bacilli mycobacteria. Ninety five percent of tuberculosis is caused by mycobacterium tuberculosis and rest of the five percent are due to atypical mycobacteria mainly mycobacterium kansasii and mycobacterium avium intracellulare complex.

Tuberculosis can involve any organ of human body but most common site is pulmonary parenchyma. This article focuses on pulmonary tuberculosis.

MODE OF TRANSMISSION OF TUBERCULOSIS:

Tuberculosis spreads by direct contact with the affected person by inhaling droplets emitted by coughing of diseased person. Children are more prone to catch infection due to relatively poor immunity. Overcrowding, homelessness and immigration are the main predisposing factors in the spread of disease. Isolation is the best measure to prevent the spread of tuberculosis.

SITE OF INFECTION:

There are two well known types of pulmonary tuberculosis, primary and post primary.

PRIMARY TUBERCULOSIS:

Primary tuberculosis occurs in those who are not sensitized to the organism previously. It mainly occurs in childhood and most cases are subclinical. Disease occurs in lower lobes of lungs with subpleural predisposition. This is the reason why pleural effusions are common in primary tuberculosis.

FEATURES OF PRIMARY TUBERCULOSIS:

There is initial patch of consolidation at the site of infection which appears as radiopaque density on plain chest x-ray. Then there is spread through lymphatics which cause regional lymph node enlargement mainly hilar lympnadenopathy. The primary lesion is called Ghon’s focus and the combined to Ghon’s focus plus lymph node is ‘primary complex’.

                PRIMARY TUBERCULOSIS WITH RIGHT HILAR LYMPHADENOPATHY

     SEVERE MEDIASTINAL AND RIGHT HILAR LYMPHADENOPATHY IN PRIMARY T.B

OUT COME OF PRIMARY COMPLEX:

Ninety percent primary infections are destined to heal with remaining ten percent leading either to latency or progression to post primary tuberculosis. Calcification may or may not occur in the process of healing.

Complications are rare in primary form but can occur at times.

POST PRIMARY TUBERCULOSIS:

It is also called reactivation tuberculosis, re-infection tuberculosis or secondary tuberculosis. It is thought now that it is mainly due to reactivation of primary lesion.

SITE OF INFECTION OF REACTIVATION TUBERCULOSIS:

Mainly effects apical or posterior segments or upper lobes or apical segments of lower lobes. These anatomical sites are well aerated leading to enhanced growth of bacteria. Lesions may cavitate due to central caseous necrosis. Unless the patient is immunocompromised, lymph node enlargement is not seen in post primary tuberculosis. There may be bronchgenic spread of disease leading to widespread bronchopneumonis.

                          POST PRIMARY TUBERCULOSIS WITH CAVITY FORMATION

Empyema formation is more common in post primary tuberculosis.

Sarcoidosis

Sarcoidosis is an inflammatory disease