Wednesday, June 30, 2010

Inverted papilloma of nose and its management

Introduction: Inverted papilloma is a benign lesion occuring in the nasal cavity and paranasal sinuses. Eventhough these tumors are classified as benign they are known to cause local destruction, known to recur and also can under go malignant transformation to squamous cell carcinoma.

History: Ward in 1854 described the macroscopic features of papilloma of nose. He used the term papillomatous neoplasm to describe this lesion. Billroth in 1855 used the term villous carcinoma to describe inverted papilloma because of its propensity to destroy local tissues and recurrence after surgery. Hopmann in 1883 used the terms hard and soft papilloma to ascertain the stoma : epithelium ratio. This classification ofcourse was not useful because the number of epithelial layers varied within the various areas of the same specimen.
Ringertz in 1938 coined the term inverted papilloma after recognizing the characteristic endophytic growth pattern demonstrated by this type of papilloma. Kramer and Som in 1935 used the term genuine papilloma of the nasal cavity. Berendes in 1966 after taking congnizance of the destructive properties of this lesion used the term Malignant papilloma to indicate this mass. Hyams in 1971 classified nasal papillomas as inverted papilloma (to indicate papillomas with endophytic growth) and fungiform papilloma. He also included a third group cylinderical papilloma to accomodate the variantions seen in these papillomas. Batsakis in 1987 used the term inverted Schneiderian papilloma indicating its origin from the Schneiderian membrane (nasal mucosa). Michaels in 1996 regarded the three types of nasal papilloma as three completely distinct entities whereas Eggers in 2005 considered these three types of nasal papillomas as hybrid lesions.

Synonyms: As indicated above various synonyms have been used to indicate inverted papilloma of nose. They include:

1.Schneiderian papilloma
2.Inverted papilloma
3.Benign papilloma of nose
4.Cylindroma
5.Malignant papilloma of nose




Definition: The mucosal lining of nose and paranasal sinuses is known as Schneiderian membrane in memory of Victor conrod Schnider who described its histology. Papillomas arising from this membrane is very unique in that they are found to be growing inwards and hence the term inverted papilloma. These papillomas are unique in their history, biology and location. Papillomas involving the vestibule is not included in this group because histologically, biologically and behavior wise it is different.



You can download the e book by clicking at the image below.

 

Friday, June 25, 2010

Rhinosporidiosis still an enigma


Introduction:
Rhinosporidiosis has been defined as a chronic granulomatous disease characterized by production of polyps and other manifestations of hyperplasia of nasal mucosa. The etiological agent is Rhinosporidium seeberi.

Theories of mode of spread:
  1. Demellow's theory of direct transmission
  2. Autoinoculation theory of Karunarathnae (responsible for satellite lesions)
  3. Haematogenous spread - to distant sites
  4. Lymphatic spread - causing lymphadenitis (rarity)





    Reasons for endemicity of Rhinosporidiosis:
    It has to be explained why this disease is endemic in certain parts of South India and in the dry zone of Srilanka. If stagnant water could be the reason then the chemical and physical characteristics of the water needs to be defined. In addition other aquatic organisms may also be playing an important synergistic reaction. This aspect need to be elucidated. Text book of microbilogy is repleate with examples of such synergism i.e. lactobacillus with trichomonas, and Wolbachia with filarial nematodes.




    These studies prompted Prof Ahluwallia et al to conclude that:


    1. Chronic inflammation almost always precedes rhinosporidiosis
    2. During this period if the patient consumes dry / fried tapioca and is malnourished it invariably leads to granulomatous polyp in the nose.
    3. Dirty pond water in which the patient takes bath causes inflammation of the nasal mucosa

      The following are the reasons making the study of this disease rather difficult:

      1. Till date no pure extract containing rhinosporidial trophozoite / spores / sporangium is available
      2. Attempts made to culture these organsim have not been successful
      3. The role of electron dense bodies in disease propagation is yet to be studied. Studies have shown that these electron dense bodies stain positively to Feulgen staining indicating that it contains nucleic acids
      4. The absence of good animal model for studying this disease is one major drawback.



       

     

     

 

Wednesday, June 23, 2010

OSCE Notes in otolaryngology


What exactly is OSCE: Objective structured clinical & Practical examination.

This system of examination consists of 15 - 20 stations. A student appearing for the exam is expected to spend 4 - 5 minutes inside a station. These stations can be simultaneously run and hence about 15 - 20 students could be examined within 1 hour. The students are expected to complete the task within the station and fill it up in the response sheet provided.
These stations should be carefully planned so that the clinical acumen of the student can be comprehensively tested. All these stations should have observers armed with check lists to assess the student's performance. Some stations are called procedure stations where in the student is expected to perform an examination technique on the patient. These procedure stations should be so designed to test the examination skill of the student.

Testing protocol for procedure stations:

1. Does the student greet the patient on entering the cubicle ?
2. Does the student explain to the patient what he is going to do in simple terms ?
3. Does the student seek permission of the patient before examining him / her ?
4. Does the student provide a screen to maintain privacy of examination ?
This system of examination consists of 15 - 20 stations. A student appearing for the exam is expected to spend 4 - 5 minutes inside a station. These stations can be simultaneously run and hence about 15 - 20 students could be examined within 1 hour. The students are expected to complete the task within the station and fill it up in the response sheet provided.
These stations should be carefully planned so that the clinical acumen of the student can be comprehensively tested. All these stations should have observers armed with check lists to assess the student's performance. Some stations are called procedure stations where in the student is expected to perform an examination technique on the patient. These procedure stations should be so designed to test the examination skill of the student.

Testing protocol for procedure stations:

1. Does the student greet the patient on entering the cubicle ?
2. Does the student explain to the patient what he is going to do in simple terms ?
3. Does the student seek permission of the patient before examining him / her ?
4. Does the student provide a screen to maintain privacy of examination ?


I have released an e book titled "OSCE notes in Otolaryngology" to cater to the needs of students who need to be trained in this particular facet of clinical examination.  You can download it by clicking at the picture below.

Thursday, June 17, 2010

Preauricular sinus and its management

Introduction:
This condition was first described by Van Heusinger in 1864. He also rightly postulated it to be congenital in nature. Most of these patients are symptomatic. Common symptoms include infections, cellulitis, and abscess formation infront of the pinna. Some of these patients may have recurrent infections leading on to embarassing discharge from the sinus. In most patients this condition is identified during routine examination involving ear, nose and throat.

You can view the e book from here.

Tuesday, June 15, 2010

Thyroid nodules Management dilemma

Introduction:
Thyroid nodule is a common occurrence. Majority of these nodules may be present without clinical evidence of thyroid disease. Statistics reveal that the incidence of palpable thyroid nodule is about 5%. Ultrasound neck is very sensitive in picking up thyroid nodules. Ultrasound can diagnose thyroid nodules even as small as ½ cm. Studies have shown that only 3-5% of thyroid nodules show malignant transformation.

Causes of thyroid nodules include:

Benign causes:

1.Goitre
2.Hashimoto's thyroiditis
3.Simple / hemorrhagic cysts
4.Follicular adenoma
5.Subacute thyroiditis

Malignant causes:

1.Papillary carcinoma
2.Follicular carcinoma
3.Hurthle cell carcinoma
4.Medullary carcinoma
5.Anaplastic carcinoma
6.Primary thyroid lymphoma
7.Metastatic malignant lesion

Tools of diagnosis as far as these thyroid nodules include:

1.Ultrasound neck
2.FNAC
3.Molecular / genetic marker analysis of fine needle aspiration biopsies





Image showing ultrasound of a benign looking thyroid nodule





You can download the full  e book from here.

Saturday, June 05, 2010

Odiosoft rhino


Introduction:

Odiosoft rhino is an equipment used to measure the sound produced by nasal airflow. Measurement of nasal airflow sounds helps us to indirectly assess the presence / absence of nasal block as well as accurately identifying the site of the block. Normal nasal airflow in humans is neither laminar nor turbulent, but a mixture of both. Hence the term transitional is used to describe nasal airflow. Simple mathematical formulae cannot be used to study nasal air flow dynamics. At higer velocities of nasal airflow turbulence also increases. This turbulence creates sound which can be recorded by recording devices such as odisoft rhino.

Airflow within the nasal cavity is regulated by 4 valves:

  1. External nasal valve
  2. Internal nasal valve
  3. Nasal turbiantes
  4. Nasal septum

Role of Fourier analysis in the study of nasal airflow:

According to Fourier the French scientist any complicated wave form can be expressed as a series of two or more simple sine waves and cosine waves.

Sound generated by air passing through nasal cavity can be recorded by placing probes containing microphone in the anterior nasal cavity. These recorded sounds are subjected to fast fourier transformation using the software called Odisoft rhino.

The recorded frequency spectrum could be classified into:

  1. Low frequency (500 – 1000Hz)
  2. Medium frequency (1-2KHz)
  3. High frequency (3-6 Khz)



Procedure:
Before emarking on recording nasal sounds, the following things should be ensured:
  1. The patient should be completely relaxed
  2. Crusts and mucous secretions from the nasal cavity should be removed
  3. While testing the right nasal cavity the probe is held in the right hand and parallel to the right nasal cavity, while the left hand is used to close the left nasal cavity.
  4. The probe should not be inserted into the nasal cavity and atleast 1 cm space should be there between the probe and the nares.
  5. Recording usually starts during non forced expiration.
  6. Recording should ideally be performed in quiet environment and acoustic artifacts like noise caused by rubbing of wires should be avoided.



Nasal sound analysis:



The frequency and amplitude of the recorded sounds should be taken into consideration. Nasal sound frequency and amplitude increases as the turbulence inside the nasal cavity increases. Nasal sound recordings in patients with deviated nasal septum have shown that the intensity of sound in lower and mid frequencies are not raised that much while the intensity of sound in high frequency was significanty elevated.
Obstruction in nasal valve area can be assessed by performing the Cottles Maneuver. Before cottle's maneuver the intensitey of sound in high frequency is elevated, while recordings performed during cottle's maneuver shows a reduction in the intensity of sound at high frequencies as the nasal air flow assumes a laminar pattern.



This whole system can also be used as a web based diagnostic service, where a patient can be asked to use the probe and the recorded sound is transmitted through internet to the diagnostic server where these sounds can be analysed and diagnosis can be made.