Pavuls presentation bonemarrow aspiration techniques

Dr.Pavulraj.S

M.V.Sc., (Veterinary Pathologist)

Research fellow

National Research Centre of Equines, India

2/15/2015 Dr.Pavulraj. S., Veterinary Pathologist, Research

fellow, NRCE, India

Bone marrow samples may be obtained by aspiration through a bone marrow needle or by punch-type biopsy through a trephine instrument (core biopsy).


fellow, NRCE, India

I. Aspirate or core biopsy

Nonregenerative anemias

Suspected bone marrow disease: myeloid or erythroid suppression, neoplasia

Leukocytosis

Polycythaemia

Certain clotting disorders, especially involving platelets

Looking for organisms that cause systemic infection Histoplasma Leishmania

2/15/2015

Dr.Pavulraj. S., Veterinary Pathologist, Research fellow, NRCE, India

II. Core biopsy

To study the structural architecture of the bone marrow when aspiration biopsies have been unsuccessful

When searching for metastatic or occult neoplasia

Certain metabolic disorders of bone


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Severe coagulopathy

DIC

Anti-vitamin k rodenticide toxicity

Severe liver failure

Severe anemia

Severe thrombocytopenia


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Two procedures Bone marrow aspirates

Bone marrow core biopsy

Steps: 1. Preparing equipment

2. Patient preparation and sedation

3. Placement of the sampling needle

4. Procuring the sample

5. Preparing slides

6. Confirming adequate sampling

7. Submitting samples to the lab


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1.Proximal humerus

2. Proximal femur - Easier in the cat

3. Wing of the ilium 4. Rib 2/15/2015


Biopsy needle (12 g for large dogs, 14 g for small dogs and cats)

Surgical scrub

10ml syringe

Local anaesthetic

Scalpel handle and blade

Microscope slides

Quick Stain (e.g., DiffQuick)

Microscope

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Rosenthal needle

Jamshidi needle 13 to 8 gauge

For core biopsy or aspiration

Fine wire use to remove the core biopsy

End of the needle is tapered to retain the core

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I. Most biopsies may be performed using local anesthesia, with or without mild sedation.

II. The position of restraining is determined by the site to be biopsied.

A. Wing of ilium 1. Large dog: standing or sternal recumbency 2. Small dog or cat: sternal recumbency with hind legs

drawn up alongside the abdomen B. Proximal femur: lateral recumbency C. Rib: sternal or lateral recumbency D. Proximal humerus: lateral recumbency E. Other less commonly used sites: ischial tuberosity,

sternum


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Shave the hair over the biopsy site, which is then prepared aseptically and infiltrated with local anesthesia down to periosteum.

Make a small stab incision in the skin with a scalpel blade.


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A. Select a 16- or 18-gauge, 1.5-inch Rosenthal biopsy needle.

B. With the stylet in place, advance the needle through the soft tissues until it meets resistance at bone.

C. Push the needle through the bone by applying pressure with a simultaneous rotating motion.

D. Decreased resistance indicates that the needle has passed through the cortex into the marrow cavity.


fellow, NRCE, India

E. After advancing the needle into the marrow, remove the stylet, attach a 12-mL syringe, and exert negative pressure on the syringe.

Evidence of pain with aspiration usually indicates that the needle is located within the marrow cavity.

When marrow appears in the syringe, aspiration is halted and the syringe disconnected.

Over aspiration may lead to contamination of the sample with peripheral blood.


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Smears are quickly made on glass slides, and any clot is saved in formalin for histologic examination.

A sample may also be submitted for culture.

F. If adequate marrow is retrieved, withdraw the needle.

G. The skin incision may be sutured or left to heal by second intention.


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Bone marrow from the humerus is obtained by palpating the bony prominence of the greater tubercle lateral to the biceps tendon.

The needle is inserted at a spot perpendicular to the long axis of the bone.


fellow, NRCE, India


fellow, NRCE, India

To retrieve a sample from the marrow cavity of the proximal femur, a bone marrow needle is advanced through the trochanteric fossa caudal and medial to the greater trochanter and directed laterally in a line parallel to the shaft of the femur.


fellow, NRCE, India


fellow, NRCE, India

Insertion of bone marrow needle through the dorsal iliac spine into the marrow cavity of the wing of the ilium.

The medial and lateral aspects of the spine are localized with the thumb and forefinger of one hand. With the other hand, the needle is directed ventrally and slightly laterally into the central portion of the wing of the ilium.


fellow, NRCE, India


fellow, NRCE, India


fellow, NRCE, India

Bone marrow aspiration from a rib. Usually the 7th, 8th, or 9th rib is chosen.

The biopsy needle is inserted at a slightly ventral angle at a point midway from the neck of the rib to the costal cartilage.


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Using a core biopsy instrument (e.g., Jamshidi bone marrow needle), advance the needle, with the stylet in place. As soon as the needle is well seated through the cortex, remove the stylet, and replace the cap and handle Advance the needle 1-2 cm further, rotating in a single

direction Stir the needle to break loose the core Remove the needle rotating in a single direction Pass the wire or stylet backward to pop the core out the

top of the needle Core 0.75-1 cm long is sufficient

Cytologies can be made by rolling the core on slides, or scraping it

Place cores in formalin for histopathology

2/15/2015



fellow, NRCE, India


fellow, NRCE, India

Pipette flecks out of the petri dish and put on glass slides immediately

Elevate one end of the slide to let extra blood run off


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Prepare gentle horizontal smears as well as vertical pull apart

preps

Use a very light touch for the horizontal preps


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I. Complications are rare.

II. Damage to adjacent structures may occur.

A. Poor positioning of the needle in the trochanteric fossa may damage the sciatic nerve.

B. Accidental pneumothorax or laceration of intercostal vessels may accompany rib biopsies.

III. Infiltration of the trochanteric fossa with local anesthetic may result in transient paresis of the sciatic nerve.


fellow, NRCE, India


fellow, NRCE, India

Advantages of aspiration

Cellular morphology is more clear Better identification of cell lineages Characteristics of malignancy

Can calculate E:M ratios Estimate regenerative responses Interpret with respect to CBC and reticulocyte count Normal 3:1 to 5:1

Maturation sequence counts are easier More mature cell stages should be present in successively greater

numbers More younger cells means leukemia, maturation arrest or

immune mediated destruction of the next stage

2/15/2015


Advantages of core biopsy

If repeated attempts to aspirate produce no fluid (“packed marrow”)

– myelophthisic disease Myelofibrosis (artifact)

If repeated attempts to aspirate produce blood only with flecks of fat Aplastic anemia (hypocellular marrow)

Can evaluate marrow cellularity

Can evaluate tissue architecture Invasion by normal looking lymphocytes indicates lymphoma

Can detect myelofibrosis or myelonecrosis

2/15/2015


1. Hypo-, normo- or hypercellular 2. Are all three cell lines present?

Erythroid, myeloid, megakaryocytes

3. Is the normal maturation pyramid present in each cell line? Fewest blast Higher numbers in each stage of maturity

4. What is the M:E ratio? Count 100-200 erythroid and myeloid cells Divide # or M by # of E

5. Decreased, normal or increase iron stores 6. Are abnormal cells present?


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Abnormal Bone Marrow Cells

Atypical cells – characteristics of malignancy leukemia or myelodysplasia

Malignant cells in clusters – metastasis

Mast cell tumors Mast cells can be present in normal marrow

Clusters suggests neoplasia

Plasma and Mott cells – chronic antigenic stimulation Ehrlichiosis or immune mediated disease

Large numbers may indicate plasma cell myeloma

Osteoblasts and osteoclasts - rare

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fellow, NRCE, India

Science

Pavuls presentation bonemarrow aspiration techniques