Patient who underwent microvascular decompression for trigeminal neuralgia

CHRONIC PAIN

NON CARDIAC CHEST PAIN

                                            

          Non-cardiac chest pain (NCCP) is a term used to describe chest pain that resembles heart pain (also called angina) in patients who do not have heart disease. The pain typically is felt behind the breast bone (sternum) and is described as oppressive, squeezing or pressure-like or pricking type. It may radiate to the neck, left arm or the back (the spine). It may be precipitated by food intake. It lasts variable periods of time and it is not unusual for it to last hours. Because the pain is similar to heart pain (called angina), patients and physicians frequently attribute this pain to the heart. In fact, many patients present to emergency rooms concerned about a heart attack and commonly undergo cardiac studies (such as EKGs, laboratory tests, stress test and even coronary angiography – where dye is injected into the heart vessels). After these cardiac tests fail to show evidence of heart disease, the patients receive the diagnosis of NCCP, leading the physician to examine other causes for this chest pain.

The main causes of NCCP are:

Gastrooesophageal reflux
Tietze Syndrome  (Costochondritis)
Chest infection
Lung tumour
Referred pain from thoracic spine
Biliary Pain
Psychological causes

The most common causes of chest pain seen in the GP surgery are non-cardiac. This is especially so with the young women. They are usually differentiated by careful history taking. Gs Gastro-oesophageal reflux disease (GERD) is very common. It presents with epigastric or mid chest burning pain, acid reflux, and relief with antacids. Patients may also complain of associated reflux symptoms such as heartburn (a burning feeling behind the breast bone) or fluid regurgitation (a sensation of stomach juices coming back toward the chest and even to the mouth frequently with a bitter or sour taste).

Pleural pain may be caused by infection, pulmonary embolism or tumour. The character of the pain is important with elucidation of pulmonary symptoms. Musculoskeletal pain, such as with Tietz syndrome, is suggested by a pleuritic character and local tenderness. Referred pain from the thoracic spine can be suggested by previous history, trauma and local tenderness. Biliary pain with epigastric or right hypochondrial discomfort, is worse with fatty foods and associated with nausea.

Psychological causes include anxiety, panic attacks, and depression. Somatic symptoms of psychological disorders are very common; however, it is also important to remember that the onset of angina itself may induce significant anxiety.

Costochondritis (Tietze's syndrome) is an inflammation of the cartilage that connects the inner end of each rib with the breastbone (sternum), otherwise known as the costochondral joint. It can occur in any age group and is most common in young adults’ especially young women. In the US, costochondritis has been shown to account for 10 per cent of chest pain episodes in the community and 30 per cent of people with chest pain presenting as an emergency to hospital.

The risk of developing costochondritis increases with any physical activity that causes trauma or strain to the ribcage. It's a benign condition, usually of short duration that resolves completely. Sometimes though, it can recur or become persistent. The predominant symptom is a sharp pain in the affected area – most commonly involving the second or third ribs that are often very tender to touch. The pain is usually related to movement, coughing and sneezing and can occur in more than one place simultaneously. Pain can also radiate into the arm and can be associated with a feeling of tightness in the chest. On examination there will be swelling and tenderness in the affected areas. The person's medical history and results of examination are usually sufficient. But if the pattern of pain suggests that it could be heart pain, it needs to be thoroughly investigated.

Treatment of costochondritis is by rest, anti-inflammatory drugs, physical therapy, and in very resistant cases, corticosteroid injections have been used as therapy for the inflamed, painful cartilage of both costochondritis and Tietze's syndrome. Ice packs applied to local swelling can sometimes help to reduce pain and inflammation. Local applications like lignocaine or anti-inflammatory creams are very helpful in most cases. Costochondritis can be aggravated by any activity that involves stressing the structures in the front of the chest and so it is better to minimise these activities until the inflammation has subsided.

Surgery for Intractable epilepsy

         Epilepsy is a condition characterized by the occurrence of seizures which are transient alterations in consciousness resulting from abnormal electrical activity in the brain. The main treatment of epilepsy is always medical but in patients who are unresponsive to or intolerant of medical therapy or have a surgical cause (eg mesial temporal sclerosis), surgery becomes an option. It is very important to determine that all medical options have been exhausted prior to surgery. Usual surgical procedures include - resective (removing portions) surgery like lesionectomy, temporal lobectomy, corpus callosotomy,hemispherectomy. Another recent advance is vagal nerve stimulation.
       Temporal lobectomy is the most common surgery for epilepsy. Complex partial seizures of temporal lobe origin constitute 25% of all epilepsy and among this a third is refractory to medical management. Indications include intractability to medical management and concordance of clinical, radiology, electrophysiological and neuropsychological data. Structures removed include anterior lateral temporal neocortex (4cm), anterior 3 cm of parahippocampal gyrus, hippocampus and amygdala. The results are usually good with upto 70% patients becoming seizure free and upto 20% having improvement in seizure controll.
       Hemispherectomy is indicated in partial seizures with contralateral hemiplegia interfering with neurodevelopmental milestones and a resectable epilepticogenic focus. Eg. Sturge Weber syndrome, Ramussens encephalitis, Infantile hemiplegic epilepsy etc. Structures removed include the frontal, parietal, occipital and lateral temporal lobes. With complete hemispherectomy, upto 85% achieve seizure free status. Postoperatively CSF pathway obstruction can occur necessitating  shunt.
        Multiple subpial resection is indicated when the seizure focus is at or extending into eloquent cortex. The principle of tis procedure is that vertical transection of eloquent cortex does not produce any deficits. The main indications include: focus in eloquent cortex, Landau-Kleffner syndrome (epileptic aphasia), Epilepsia partialis continua and failed hemisperectomy in Rasmussens disease.
Multiple resections are done using the subpial transection hook. The results are usually good and 75% of patients with intractable seizures have upto 90% improvement.
       Corpus callosotomy involves division of the corpus callosum to prevent spread of seizure discharge. This will help in  preventing secondary generalization (spread) of the seizures. The main indications include poorly controlled generalised seizures but no primary focus can be demonstrated eg: Lennox-Gastaut syndrome, multi centric CPS with secondary generalization. Complete sectioning of corpus callosum is essential for good results; 80% 0f patients reported more than 50% reduction in seizure frequency. Sequele include reduced spontaneity of speech, non dominant limb apraxia which are transient and interhemispheric sensory dissociation.
      Vagal nerve stimulation is a new method being used because not all patients with medically refractory epilepsy are candidates for resective surgery. Resective surgery is not always an option for medically refractory seizures. Vagus nerve stimulation (VNS) is an adjunctive treatment for certain types of intractable epilepsy and major depression. Vagus nerve stimulation (VNS) is designed to prevent seizures by sending regular, mild pulses of electrical energy to the brain via the vagus nerve. Indications include patients who have failed surgery before, patients who require extratemporal surgery in eloquent area or corpus callosotomy or the patients’ choice.

PARKINSONISM AND OTHER MOVEMENT DISORDERS

        

                Movement disorders are neurological conditions that affect the speed, fluency, quality, and ease of movement. Abnormal fluency or speed of movement (dyskinesia) may involve excessive or involuntary movement (hyperkinesia) or slowed or absent voluntary movement (hypokinesia). The commonest movement disorder is Parkinson’s disease which manifests with tremors, rigidity, slow movement (bradykinesia), poor balance, and difficulty in walking. It affects 1 – 2% of people above 60 yrs but in India it is seen in younger people also (upto 15%). Treatment of movement disorders like Parkinsonism is predominantly by drugs and drugs are very effective in most cases. But a good number of patients either come out of good control in the long term or develop side effects of drugs. Such patients are surgical candidates. Previously ablative (destructive) surgeries like pallidotomy were used for this problem but presently the treatment of choice is subthalamic nucleus deep brain stimulation (DBS). Ablative surgeries are permanent and non reversible and the side effects are much more and so ablative surgeries are not much practiced.

Indications for DBS in Parkinsonism:

             1. Advanced Parkinson’s disease with disabling motor fluctuations and dyskinesias refractory to drug changes.
              2. Levodopa induced dyskinesias.
              3. Medication refractory symptoms with significant disability and interference with daily activities including writing, feeding, dressing, etc.
              4. No significant cognitive impairment and no major psychological problems.
              5. 10 years after diagnosis.
              6. Patients understand and accept therapy. 

Parkinson”s Disease (PD) can be said to be having three stages. 

Stage 1 is early PD where most of the people can be managed with medical treatment; however 20% of the patients (especially with tremors) who do not respond to conservative treatment can be offered surgery. 

Stage 2 of PD is where medical treatment starts loosing its efficacy, is associated with side effects like hallucinations and dyskinesias and causes wide fluctuations of off and dyskinetic state. Surgery is very useful at this stage. This stage occurs after 5 or more years of disease. Besides dyskinesias and motor fluctuations, other indications include severe pain and hallucinations.

Stage 3 of PD is the most advanced stage when the patient is virtually bed bound and barely responds to medical treatment, and has significant side effects. Surgery may or may not be possible in this case.
      

                 Deep brain stimulation (DBS) for Parkinsonism involves stimulating the subthalamic nucleus (STN) with specially made electrodes. The surgery is done under local anaesthesia. Surgery for Parkinsonism usually resolves tremor, dyskinesias, pain and hallucinations and symptoms which are improved by drug therapy are maximally improved with surgery. Tremor improves by 80%-100%, slowness (Bradykinesia) by 50%-60%, stiffness (Rigidity) by 50%-70%, gait, freezing, and balance 50%, dyskinesias & dystonia  (drug induced) 80%- 90% and motor fluctuations are virtually eliminated. Independence and quality of life are substantially improved. Complications include haemorrhage (2-3%), Infection (1 -3%), mechanical breakage (1-5%) and cognitive decline (2%).

                 DBS is also done in other movement disorders like Dystonia (including cervical dystonia) and in cases of chronic pain.

                 Recently deep brain stimulation of the nucleus accumbens is being done in cases of intractable alcoholism.

PAIN IS UNAVOIDABLE BUT DO WE NEED TO SUFFER IN THIS 21st CENTURY

Chronic Pain: The silent epidemic
       Chronic pain is pain persisting or recurring even after treatment for more than 6 months. Chronic pain includes persistent headache, neck and shoulder pain, non cardiac chest pain, low backache, pain in the hands and legs, pain in the joints etc. Three groups of people need special mention: people with pain due to cancer or chemotherapy (cancer pains), people with severe pain in the legs due to diabetes (diabetic neuropathy), and people who had had surgery for back pain before but has no relief of pain (Failed Back surgery syndrome).
       Anything from a bad mattress to bad posture to major problems like tumours (including cancers) or degenerative diseases can cause chronic pain. Unfortunately chronic pain carries with it a psychological component which can lead to anxiety/ depression and further problems. So treatment needs to be individualised and specialised.  Chronic pain interferes with every aspect of life, including work, sleep, relationships etc. Studies in students have shown a strong relationship between chronic pain and academic performance. Many studies have shown the direct negative relationship between career growth and chronic pain. There are also studies which have shown chronic pain in the young could cause infertility. Thus chronic pain affects our day to day quality of life and also causes financial and other family problems.
          Treatment of chronic pain is highly specialised and involves drug therapy, psychotherapy, physical therapy etc. Many countries have specialised pain centres and university departments. Infact the American Congress had declared the ten-year period that began January 1, 2001, as the Decade of Pain Control and Research. Unfortunately in our country chronic pain is not considered a big issue because of lack of awareness of its consequences; patients go from doctor to doctor seeking relief but never get the cure.
         Majority of patients with chronic pain can be treated by medical and physical means. This is done in a series of steps. Initially oral medications including adjuvants are tried along with physiotherapy, rehabilitation and psychological therapy as necessary. If there is no relief, then oral opioids may be considered especially in cancer pain. Simultaneously therapeutic nerve blocks may be recommended in selected cases. If these are not effective or the side effects are severe, then advanced therapies are indicated. These include:
1. intrathecal drug delivery
2. neurostimulation,
        Intrathecal drug delivery systems can deliver drugs like morphine directly into the cerebrospinal fluid or CSF (the fluid around the brain and spinal cord) . The advantage is that the drug acts directly on receptors in spinal cord. So the dose of drug required is much less (about 1/200^th of oral dose with morphine). As a result side effects like constipation/drowsiness do not occur. Also there is no systemic absorption so no problem with tolerance and addiction liability. There are many studies that have shown that intrathecal morphine pumps are effective in reducing pain in more than 80% of patients. Also many studies have shown the very good safety profile of this treatment. Intrathecal morphine is indicated in diffuse cancer pain, failed back surgery syndrome, osteoporotic pain etc. Intrathecal baclofen is indicated in spasticity due to cerebral palsy, spinal cord injury, multiple sclerosis, brain hypoxic injury, severe head injury, and metabolic diseases. Several articles have shown that intrathecal baclofen has significant functional benefits and worthwhile acceptable cost / benefit ratio. We have a good number of patients who were unable to walk due to weakness / stiffness of legs but have improved well after baclofen pump insertion.
           Spinal cord stimulation is Indicated in conditions like failed back surgery syndrome, intractable diabetic neuropathy pain, complex regional pain syndromes (CRPS) , pain in brachial plexus injuries, pain due to peripheral vascular disease, refractory angina (where bypass or angioplasty is not possible and drugs are not effective). It is also useful in pain in the arm, phantom limb pain (after amputation), neuralgias like trigeminal neuropathies etc. The method is to introduce stimulating electrodes in the dorsal extradural space which stimulate the dorsal column. The results show that this is very effective in 60 – 80% of patients especially in failed back surgery syndrome, diabetic neuropathy, refractory angina etc.

FUNCTIONAL NEUROSURGERY

WHAT IS FUNCTIONAL NEUROSURGERY  ?

General neurosurgery deals with brain and spinal cord tumours, head injuries, problems in children like hydrocephalus, surgery for spinal problems like disc prolapsed, spinal canal stenosis etc. Functional neurosurgery includes surgery for intractable chronic pain (including cancer pains), surgery for movement disorders like Parkinsonism, surgery for severe spasticity of various causes, surgery for epilepsy, surgery for psychiatric problems like depression, OCD etc. The latest innovations in functional neurosurgery are treatment of addiction and treatment of people in coma for some time (called persistent vegetative state).