Rutucharya (ऋतुचर्या)
Ayurveda has put forward various guidelines and regimens encompassing components like diet and lifestyle to help people acclimatize to seasonal enforcement easily. This helps individuals to maintain homeostasis of internal environment of their body despite fluctuating external climatic conditions. These guidelines and seasonal regimens are known as ‘Rtucharya’ (Samskrit: ऋतुचर्या). Observance of such behavior, lifestyle and dietary modifications is immensely useful in preventing diseases which might develop due to seasonal variations and individual's poor immunity. Naturally, Rtucharya forms integral part of preventive healthcare described in Ayurveda and is one of the exclusive subjects in this traditional system of medicine. Main theme of this topic is to make people aware concerning the methods to live in accordance with the environment.
परिचयः ॥ Introduction
Rtucharya has been described in almost all the authoritative Ayurveda classics. Ayurveda believes that every change in the external environment and season affects the internal environment of the human body. This leads to imbalance of Doshas (दोषाः) which control entire mechanism of the union of body, mind & life energy known as Ayu (आयुः। life). This imbalance further leads to development of diseases. Therefore, it is important to understand the role of seasonal variations in diseases development as well as the measures to correct this imbalance and achieve right balance of bodily elements. Under the topic of Rtucharya, Ayurveda acharyas have provided such measures in the form of dietary and lifestyle modifications, to maintain the equilibrium of internal environment of body even in the presence of fluctuating external environment and climatic conditions. These measures have been put forward after keen observation of seasonal characteristics and their effect on the state of Doshas and Dhatus (धातवः) in the Purusha (पुरुषः। human being). In the clinical settings, observance of such regime has been found extremely useful especially in the cases where individuals who fall sick frequently because of seasonal variations owing to their poor immunity.
ऋतुसात्म्यस्य उपयोगित्वम् ॥ Practical utility of observing Rtucharya
Acharya Charaka has said that, diet and daily activities of an individual are responsible to maintain or disturb the internal balance of bodily elements. Thus, if one can modify diet and lifestyle or activities according to changes in external environment, one can achieve good health and wellness.
तस्याशिताद्यादाहाराद्बलं वर्णश्च वर्धते| यस्यर्तुसात्म्यं विदितं चेष्टाहारव्यपाश्रयम्|| (Char. Samh. 5.3)[1] tasyāśitādyādāhārādbalaṁ varṇaśca vardhate| yasyartusātmyaṁ viditaṁ ceṣṭāhāravyapāśrayam|| (Char. Samh. 5.3)
Meaning: A person who knows the ritusatmya (getting accustomed to suitable changes in diet and behavior according to seasons), and practices such habits accordingly, and whose diet consists of various types of food articles (with properties such as ashita, pitta lidha , and khadita), has his strength and luster enhanced, and he leads a healthy, long life.
व्युत्पत्तिः॥ Etymology
The word Rtu (ऋतुः।) means “to go.”[citation needed]
It is the form in which the nature expresses itself in a sequence in particular and specific in present forms in short, the seasons.
Charya (चर्या।) means regimen[citation needed]
Thus, Rtucharya (ऋतुचर्या) means the regimen to be adopted during the changing states of the nature or climate.
Bharatiya Kalamana and place of Rutus
Kala (Samskrit : कालः) means "time period" in a broad sense. The concept of time is explained systematically in vedanga jyotisha (astronomy). It is significant that time has been considered both at the microcosmic and the macrocosmic levels. Various Puranas also describe Kalapramana that existed previously. The measurement of time is known as Kalamana. Such time measurement has also been explained in Ayurveda texts like Charaka Samhita and Sushruta samhita, and it is in line with the measurement explained in the other bharatiya shastras. The placement of rutus in this measurement system is of importance in the context of Rutucharya in this topic.
Acharya Charaka and Sushruta, have divided year in to the 6 segments calling this as Shadangas of the year. And it is also stated that, this segmentation is for the purpose of of svasthavrutta (healthy regimen) in different seasons. As per them, A year (samvatsara) is divided into six parts by seasons. Among them, when the Sun is in northward position to the Earth, that part of the year is called adana kala and includes three ritu starting from shishira, vasanta and grishma. When the Sun is in a position of southwards of the Earth, the period is called visarga kala and includes three ritu starting from varsha, sharad and hemanta. [2]
Acharuya Sushruta gives even more detail segmentation of the time itself and provides position of the rutus in it. As per Sushruta, the smallest part of the time is akshinimesha, which refers to the time required to blink the eyelid whereas, the big part of the time is year known as Samvatsara which further makes Yuga known as the largest part in the time measurement. The same has been depicted in the adjacent picture. Till year the cyclical occurance of the time is easily perceptible to everyone therefore the segmentation of the year upto the year only has been given in the picture. However, the biggest part is the Yuga. [3]
ऋतुविभागाः॥ Classification of season
According to Ayurveda, the year is divided into two periods Ayana (अयनम्। solstice) depending on the direction of movement of sun. Each is formed of three Rtus (ऋतुः। season). Thus, A year consists of six seasons [4] as listed below,
| No. | Rutu | Corresponding season | Ayana | ||
|---|---|---|---|---|---|
| 1 | Shishira (शिशिरः) | Winter | Uttarayana (northern solstice)= | mid-January to mid-July | According to modern science, this can be compared with the gradual movement of earth around the sun to the position, in which the rays of the sun falls perpendicularly at 30 degree meridian of the North Pole on June 21st every year, called as summer solstice. The northward journey of the Sun from Tropic of Capricorn to Tropic of Cancer happens. |
| 2 | Vasanta (वसंतः) | Spring | |||
| 3 | Grishma (ग्रीष्मः) | Summer | |||
| 4 | Varsha (वर्षा) | Monsoon | Dakshinayana (southern solstice) | mid-July to mid-January | According to modern science, this can be compared with the gradual movement of the earth around the sun to the position, in which the rays of the sun fall over 30 degree meridian of the South Pole perpendicularly on December 21st every year, is called as winter solstice. The southward movement of the Sun occurs from Tropic of Cancer to Tropic of Capricorn. |
| 5 | Sharad (शरदः) | Autumn | |||
| 6 | Hemanta (हेमंतः) | late autumn |
As Ayurveda has its origin in India, the above seasonal changes are observed predominantly in Indian subcontinent.
उत्तरायणस्य दक्षिणायनस्य च परिणामाः ॥ Effect of Uttarayana and Dakshinayana
During Uttarayana (उत्तरायणम्) period, warmness and dryness in weather increases. It has an overall debilitating effect on surrounding environment, of which human being is also a part. As a result, it brings about dryness in the body and reduces the Bala (बलम्। strength) of the individual. [4]
At the time of Dakshinayana (दक्षिणायनम्) period, when cool sets, and due to which anabolic activity dominates over the catabolic activity in the environment, the strength of person enhances.[4]
Months of Hindu calendar 2 lists of seasons
As per Hindu calendar in Bharata, for every 2 months there is one season. Therefore for 12 months there are 6 seasons. However the seasons are listed with little variation in the names in 2 different cases. The list of season and months in Hindu calendar is given below,
| No. | Rtu list 1 | Hindu calendar months | Rtu list 2 | Hindu calendar months | Corresponding season |
|---|---|---|---|---|---|
| 1 | Shishira (शिशिरः) | Magha, Phalguna | --- | --- | Winter |
| 2 | Vasanta (वसंतः) | Chaitra, Vaishakha | Vasanta (वसंतः) | Falguna (फाल्गुन), Chaitra (चैत्रः) | Spring |
| 3 | Grishma (ग्रीष्मः) | Jyeshtha, Ashadha | Grishma (ग्रीष्मः) | Vaishakha (वैशाखः), Jyeshtha (ज्येष्ठः) | Summer |
| 4 | --- | --- | Pravrt / Pravrush (प्रावृट्/प्रावृष्) | Ashadha (आषाढः), Shravana (श्रावणः) | Early Monsoon |
| 5 | Varsha (वर्षा) | Shravana, Bhadrapada | Varsha (वर्षा) | Bhadrapada (भाद्रपदः), Ashvin (अश्विन्) | Monsoon |
| 6 | Sharad (शरदः) | Ashvin, Kartika | Sharad (शरदः) | Kartika (कार्तिक), Margashirsha (मार्गशीर्ष) | Autumn |
| 7 | Hemanta (हेमंतः) | Margashirsha, Pausha | Hemanta (हेमंतः) | Pausha (पौष), Magha (माघ) | Winter or late autumn |
Acharya Sushruta has explained the reason behind mention of 2 different lists of rutus in Ayurveda treatises. As per his opinion, when the association of the rutus with the strength of the living beings especially the human has to be understood along with its relation to the rasa dominant in the nature at that time of the year, then the first list of rutus that includes Shishira rutu is considered. Whereas, when the specific season to undergo Panchakarma procedure in order to get excess doshas eliminated from the body for healthy individual also, then the second list of rutus that includes Pravrut rutu is referred. [5]
As per the opinion of acharya Kashyapa, season counting and variations in it are dependent upon which part of the Bharata have they been counted. He says that on the south of the river ganga the rains stretch for a longer period during the year while in the northen part of river ganga, the winter extends for a longer period than rains. Therefore in south India the season are counted in a different way than seasons in the north India.
संज्ञाभेदं च देशभेदेनाह काश्यपः-"भूयो वर्षति पर्जन्यो गङ्गाया दक्षिणे तटे| अतः प्रावृट् च वर्षाश्च ऋतू तत्र प्रकल्पितौ|| तस्या एवोत्तरे देशे हिमवद्विन्ध्यसङ्कुले| भूयः शीतमतस्तत्र हेमन्तशिशिरावुभौ||" इति| दक्षिणदेशीयैर्वृष्टिसंबन्धिनोर्द्वयोः प्रावृड्वर्षाख्यत्वं कृत्वा, पारिशेष्याच्छीतसम्बन्धिनोर्द्वयोः शरद्धेमन्ताख्यत्वं कृतम्| उत्तरदेशीयैस्तु शीतसम्बन्धिनोर्द्वयोर्हेमन्तशिशिराख्यत्वं कृत्वा, पारिशेष्याद्वृष्टिसम्बन्धिनोर्द्वयोर्वर्षाशरत्संज्ञत्वं कृतमित्यर्थः| वृष्टिशीतबाहुल्योपन्यासस्तत्रान्वर्थसंज्ञार्थः , न च संज्ञासङ्करे लक्षणसङ्करः, दोषाणां दोषधातुमलसंज्ञावत्|
ऋतुसन्धिः ॥ Transition zone between 2 Rtus
When a new season starts and the previous ends, there is a period which shows transition in weather. Precisely, the last week of the previous season and the the first week of the next season is such a transition period and it is called as Rutusandhi in Ayurveda. This time is considered crucial since one is expected to systematically switch from the regimen of previous season to that of the coming season. If done systematically as described in Ayurveda, one can maintain health even if the season changes. This is the period when most of the people fall sick and thus following the regime given in Ayurveda is the key to maintain immunity, health and wellbeing even during the season change.
ऋत्वोरन्त्यादिसप्ताहावृतुसन्धिरिति स्मृतः|
तत्र पूर्वो विधिस्त्याज्यः सेवनीयोऽपरः क्रमात्||५८||
असात्म्यजा हि रोगाः स्युः सहसा त्यागशीलनात्| (Asht. Hrud. 3.58)[6]
Ayurveda acharyas clearly say that, if the regime of the past season is suddenly stopped and the new regime is immediately adopted it can cause asatmyaja rogas viz disease due to intolerance or unsuitability.
Yajnas in Rutusandhikala
Rutusandhi is the period between two adjacent rutus. Specifically last 7 days of the preceding rutu and the first 7 days of the upcoming rutu.
ऋत्वोरन्त्यादिसप्ताहावृतुसन्धिरिति स्मृतः| तत्र पूर्वो विधिस्त्याज्यः सेवनीयोऽपरः क्रमात्||५८|| असात्म्यजा हि रोगाः स्युः सहसा त्यागशीलनात्| (Asht. Hrud. 3.58--59)[7]
It is that period when the climatic conditions of the previous season start changing and the new season starts lying its foundation. Therefore the weather in this period is changing or fluctuating. Due to the changing unstable climate, inner equilibrium of doshas also is affected and hence a person become more vulnerable to develop different diseases. These are counted under the seasonal flu or allergies in western medicine. Ayurveda has advised to adopt to the regime of both the seasons moderately and switch from one to the other gradually in order to prevent the diseases developing out of sudden changes in diet and activities known as 'Asatmyaja rogas'. One can find various references in Brahmanas of Yajnas suggested in Rutusandhi period to maintain health. [8] In Gopatha Brahmana there is a sutra which states that, maximum diseases occur in the Rutusandhi period thus, maximum Yajnas are performed during the Rutusandhi period. [9]
यद् ऋत्वियाद् असृजत् तद् ऋतूनां ऋतुत्वम् । (जैमिनीय ब्राह्मण् ३/१)
In Rutugraha prakarana of Shatapatha Brahmana, different homas for different rtus have been suggested. [10]
ऋतुसन्धिषु व्याधयः जायन्ते ऋतुसन्धिषु यज्ञाः क्रियन्ते।
Greeshma, Varsha and Hemanta have been considered to be main 3 rtus.[11] In Shatpatha Brahmana, Vasanta, Greeshma and Varsha are said to be Deva Rtus whereas Sharada, Hemanta and Shishira have been said to be Pitru rtus. [12]
Rutushtoma Yajan has been said to have potential to revitalize and reset the Rtus to normal as per Jaminiy abrahmana. [13]
Shroutsutras suggest Yajanas in Vasanta, varsha and Sharada ruts as per the aggravating Doshas in that period as described below,[8]
- Vasanta - Vaishwadeva (Jyotishtoma, agnishtoma/Somayaga) (For Kapha related problems)
- Varsha - Varunapravas (For Vata related problems)
- Sharada - Sakamedha (For Pitta related problems)
Special emphasis has been given on performing YAjnas in Varsha rtu (Rainy season). [8]
Agni, soma, anila controlling creation and maintenance in nature and human body analogy
विसर्गोदानविक्षेपैः सोमसूर्यानिला यथा |
धारयन्ति जगद्देहं कफपित्तानिलास्तथा [१] ||८|| - Su. Su 21.8
Commentary- विसर्गादानविक्षेपैः कर्मभिर्यथासङ्ख्येन चन्द्रादित्यवाता यथा जगद्धारयन्ति, तथा कफादयस्त्रयो यथासङ्ख्येन विसर्गादिभिः कर्मभिर्देहं धारयन्तीति समुदायार्थः| विसर्गः सर्जनं ‘बलस्य’ इति शेषः; आदानं ग्रहणं बलस्यैव; विक्षेपः शीतोष्णादीनां विविधप्रकारेण प्रेरणम्||८||
Dosha and season relationship
Any individual is considered Svastha (Healthy when he has a certain state of Doshas, Agni, dhatus, malas, a certain state of Atman, indriyas and manas. The same has been explained by Acharya Sushruta as follows,
समदोषः समाग्निश्च समधातुमलक्रियः | प्रसन्नात्मेन्द्रियमनाः स्वस्थ इत्यभिधीयते ॥ (Sush. Samh. 15.41)[14] Meaning: Svastha (Healthy) person means, the one who has sama (balanced level of) doshas, sama agni (digestive fire), Sama metabolism generating balanced level of dhatus and malas as well as Prasanna (Happy state of ) atman (life energy / soul), Indriyas (Sensory and motor organs) and manas (mind).
Therefore, from the point of view of preventive healthcare, it is of utmost importance to maintain the balanced state of all these factors mentioned above which can also be called as the determinant of the health. Along with the other factors like diet, lifestyle, other habits etc kala (time) is one highly important factor that can cause diseases by disturbing the balanced state of doshas. The way in which this happens has been beautifully explained by Ayurveda acharyas in the topic of rutucharya. It was deeply studied and explained as to how the changing seasons, weather in a sequence bring about the changes in doshas, agni and strength. Particularly how seasons affect balanced state of individual doshas has been explained in texts and is depicted in the picture below.
Strength and season relationship
Association or effect of each season on overall strength known as Balam in Ayurveda has been clearly explained by all the Ayurveda Acharyas in their texts. How ayanas and seasons affect strength is explained.
During Uttarayana (उत्तरायणम्) period i.e. in Shishira, Vasanta and Grishma rutus, warmness and dryness in weather increases. It has an overall debilitating effect on surrounding environment, of which human being is also a part. As a result, it brings about dryness in the body and reduces the Bala (बलम्। strength) of the individual. [4]
At the time of Dakshinayana (दक्षिणायनम्) period i.e. in Varsha, Sharada and Hemanta rutu, when cool sets, and due to which anabolic activity dominates over the catabolic activity in the environment, the strength of person enhances.[4]
Understanding this association and impact of the seasons is very important to decide the diet, lifestyle, treatments and plan activities in seasons. The same is depicted in the table.
| Rutu | Balam
(Strength and overall Health) |
|
| Shishira | BEST | |
| Vasanta | Moderate | |
| Grishma | Poor | |
| Varsha/
Pravrut |
Poor | |
| Sharada | Moderate | |
| Hemanta | BEST |
ऋतुचर्या विधानम्॥ Seasonal Diet and Lifestyle Regimen
After keen observation of external climatic conditions in a particular Rtu (ऋतुः। season) and their reflections in the Purusha (पुरुषः), Ayurveda scholars found a close association between external environments and Body's internal environment. It is believed and experienced that, for every change in external conditions, Doshas (दोषाः) and other body elements like Agni (अग्निः), Dhatus (धातवः) get affected. Change in their normal state creates temporary imbalances which leave body vulnerable for attack by various diseases. Thus, if one wishes to maintain health in spite of any change in external environment, one must consciously understand the changing weather and practice specific diet and lifestyle interventions proposed by Ayurveda in order to nullify the effects reflected in body.
Ayurveda acharyas have proposed following diet and lifestyle guidelines for 6 Rtu (ऋतुः। seasons) to correct the imbalances of Doshas, Agni, strength and internal environment of body created by changes in weather due to seasonal rotations.[15]
| No. | Rutu | Corresponding season | Diet | Lifestyle | ||
|---|---|---|---|---|---|---|
| Do's | Dont's | Do's | Dont' | |||
| 1 | Shishira Rutucharya | Winter | Cereals and pulses, wheat/gram flour products, new rice, corn, and others, are advised. Ginger, garlic, Haritaki (fruits of Terminalia chebula), Pippali (fruits of Piper longum), sugarcane products, and milk and milk products are to be included in the diet. | Foods that can aggravate Vata dosha should be avoided in order to keep check on naturally aggravating Vata due to increasing cold. Thus, foods that are pungent, astringent and bitter in taste, cooling in nature and light on digestion should be avoided. | Various Panchakarma procedures like Abhyanga i.e. Massage with warm oil, scrubbing with herbal powder or pastes are considered to be beneficial if followed on daily basis in this season. Use of warm water for bathing, exposure to natural heat or sunlight, wearing warm clothes is also advisable. | Exposure to cold wind of this season, staying awake for late nights may further aggravate Vata dosha in this time. Thus its advisable to avoid these lifestyle factors. |
| 2 | Vasanta Rutcharya | Spring | One should take food made up of barley and wheat | One should avoid heavy, sour, unctuous and sweet food items | one should regularly resort to physical exercise, dry massage, medicated smoking, gargling, and collyrium. Bathing and cleaning of excretory orifices should be done with lukewarm water. | One should not sleep during the daytime. |
| 3 | Grishma Rutucharya | Summer | Foods and drinks having sweet, cold, liquid and unctuous qualities are considered beneficial | One should stop taking salty, sour, pungent and hot food | Enjoy the coolness of gardens, cold water and flowers whenever possible to negate the fatigue developing from excessively hot and dry climate. | Physical exercise and excess sexual intercourse should be avoided. |
| 4 | Varsha/Pravrut Rutucharya | Monsoon | one should predominantly take sour, salty and unctuous food to alleviate vata. Make use of honey in food and drinks. | Since the digestive strength is poor and Vata dosha is aggravated, one should avoid food items that are heavy on digestion and lead to flatulence. | Practice dry massage, reside at places with low humidity, use fragrances, garlands to keep the surroundings fresh and cheerful. This is also considered the ideal season for taking Basti which is one of the 5 types of Panchakarma treatments. | Daytime sleeping, contact with dew, river water, intense physical exercise, exposure to sun rays and excess sexual intercourse should be avoided. |
| 5 | Sharada Rutucharya | Autumn | Foods that are sweet or bitter in taste, cooling in nature and light on digestion should be consumed to remain fit. These foods can then pacify vitiated Pitta. Wheat, green gram, sugar candy, honey, , flesh of animals having habitat in dry land (Jangala Mamsa) can be consumed. | In order to keep a check on naturally aggravating Pitta dosha, it is advised to avoid hot and spicy food. Few food stuffs which are to be avoided - fat, oils, meat of aquatic animals, curds, etc. | Medical procedures, such as Virechana (purging), Rakta-Mokshana (blood letting) are ideally performed in this season. It is recommended to observe the natural urge for food and eat only after having the natural desire for food. Its best to avoid overeating. It is also recommended to take water purified by the rays of sun in day time and rays of moon at night time for drinking, bathing, etc. Use of fresh, cooling flowers in surrounding, use of cooling fragrances like Sandalwood can be made as scents and also for local application on body. It is said that moon rays in night are conducive for health. On this ground various rituals wherein staying awake late nights is expected are followed like Kojagiri pournima. | Exposure to sunlight, heat, Daytime sleep and excessive eating is to be avoided. |
| 6 | Hemanta Rutucharya | late autumn | One can have more of sweet, sour, and salty foods this season. This season also necessitates intake of food that is unctuous in nature. Naturally sweets, desserts and creamy foods can be enjoyed in this eason with little health risk. Cereals and pulses, new rice, flour preparations, green gram, Black gram, etc. should be used. Various meats, fats, milk and milk products, sugarcane products, Shidhu (fermented preparations), Tila (sesame), and so on, are also beneficial at this time. | Any type of diets which possess capacity to develop feeling of lightness, cold, and dryness in body should be avoided. | Vyayama (Exercise), abhyanga (body and head massage), use of warm water, sunbath, application of fragrant herbs having hot potency can be used, sufficient warm clothing, sexual indulgence with one partner, residing in warm places is recommended | Must avoid exposure to strong and cold wind. Better to avoid diwaswapa daytime sleep. |
Rtu Haritaki
This is one the specialty topic from Bhavapraksha samhita (भावप्रकाश संहिता) of Laghutrayee (लघुत्रयी). While describing the properties of Haritaki (Terminalia chebula) Acharya Bhavamishra has thrown light on utility of this single multipurpose herb in all seasons to gain Rasayana (रसायनम्) effect. This single herb when taken with various adjuvants suggested after considering the seasonal dosha dominance, can show rejuvenating effect. The adjuvant to be taken with Haritaki, as per the Rtu (seasons) is listed below,
| Season | Adjuvant for Haritaki |
|---|---|
| Varsha (वर्षा) | Saindhava (सैन्धवम्) |
| Sharad (शरदः) | Sharkara (शर्करा) |
| Hemant (हेमन्तः) | Shunthi (शुण्ठी) |
| Shishir (शिशिरः) | Pippali (पिप्पली) |
| Vasant (वसन्तः) | Madhu (मधु) |
| Grishma (ग्रीष्मः) | Guda (गुड) |
The dosage of haritaki, time of consumption and other individual specific administration details should be obtained from a qualified Vaidya after complete evaluation of Prakrti and Roga.
References
- ↑ Charaka Samhita (Sutrasthanam Adhyaya 5 Sootram 3)
- ↑ Charaka Samhita (Sutrasthanam Adhyaya 6 Sutra 4)
- ↑ Sushruta Samhita (Sutrasthanam Adhyaya 6 Sutra 5-6)
- ↑ 4.0 4.1 4.2 4.3 4.4 Sushruta Samhita (Sutrasthanam Adhyaya 6 Sootram 7)
- ↑ Dalhana's commentary on Sushruta Samhita (Sutrasthanam Adhyaya 6 Sutra 10)
- ↑ Ashtanga Hrudayam (Sutrasthanam Adhyaya 3 Sutra 58)
- ↑ Ashtanga Hrudayam (Sutrasthanam Adhyaya 3 Sutra 58-59)
- ↑ 8.0 8.1 8.2 Sharma Priyavrata. Ayurveda ka vaignanik itihas. Page (480-2)
- ↑ Gopatha Brahmana (3/1/19)
- ↑ Shatapatha Brahmana (4/2/5)
- ↑ Jaiminiya Brahmana (2/360)
- ↑ Shatapatha Brahmana (2/1/3)
- ↑ Jaiminiya Brahamana (2/211)
- ↑ Sushruta Samhita (Sutrasthanam Adhyaya 15 Sutra 41)
- ↑ Thakkar J, Chaudhari S, Sarkar PK. Ritucharya: Answer to the lifestyle disorders. Ayu. 2011;32(4):466–471. doi:10.4103/0974-8520.96117