MLT GlobeHisto & Cyto Techniques: Cytology – page 3
80 Histo & Cyto Techniques MCQs on Cytology with answers and explanations.
Which device, rotated fully several times at the os, is designed to sample the whole transformation zone?
The broom's long central bristles enter the canal while outer bristles cover the ectocervix, collecting the entire junction. Fornix and vaginal samples miss it.
If a CSF sample for cytology cannot be processed promptly, it should be:
CSF is protein-poor, so cells degrade quickly. Refrigeration with 50% ethanol pre-fixative slows this; freezing ruptures cells.
If transport of a sputum specimen for cytology is delayed, it is commonly preserved in:
70% ethanol pre-fixes cells while limiting excessive hardening of mucus. Saline gives no fixation, and formalin is unsuitable for Pap staining.
Inflammatory cells are normally most plentiful in smears taken from the:
Polymorphs are common in endocervical and posterior fornix material, so they alone do not indicate infection. Lateral wall smears are relatively clean.
Which needle is designed for closed pleural biopsy?
The Abrams needle cuts pleural tissue with a notched inner cannula. Jamshidi and Islam needles are for bone marrow trephine, and Menghini for liver.
Endometrial cells in a postmenopausal woman's cervical smear most importantly raise concern for:
Endometrial cells after menopause are abnormal and warrant evaluation for endometrial hyperplasia or carcinoma. Polyps and fibroids may also shed them.
Endometrial cells are a normal finding in a vaginal smear in each situation EXCEPT:
Endometrial shedding occurs with menstruation and after pregnancy ends. In late pregnancy the endometrium (decidua) is not shed, so its cells are unexpected.
During FNA of a palpable lymph node, what should be done just before the needle is pulled out of the lesion?
Suction is released inside the lesion so the sample stays in the needle rather than being sucked into the syringe barrel and mixed with blood.
Transthoracic fine-needle aspiration is most useful for which type of lung lesion?
Percutaneous aspiration targets peripheral masses that bronchoscopy cannot reach and that do not exfoliate into the airways for sputum or washings.
Which imaging method is most widely used today to guide needle aspiration of a small peripheral lung nodule?
CT gives precise needle localisation for small lung nodules; fluoroscopy or ultrasound are alternatives only for suitable lesions.
Before transthoracic lung aspiration, local anaesthetic is infiltrated from the skin down to which depth?
The parietal pleura is pain-sensitive, so anaesthesia is carried down to it; the lung parenchyma has no somatic pain supply.
Which needle size range is typical for transthoracic fine-needle aspiration of lung lesions?
Thin 22–25 G needles give enough cells while limiting pneumothorax and bleeding; 12–16 G are core/drainage sizes.
Why is the needle kept in a lung lesion for only a few seconds during transthoracic aspiration?
Minimising needle dwell time and passes limits pleural injury and bleeding; prolonged suction mostly adds blood, not diagnostic cells.
Why must Pap smears pass through absolute ethanol, not only 95% ethanol, before xylene?
Xylene is immiscible with water; carried-over water causes cloudy, poorly cleared smears, so complete dehydration is needed.
Percutaneous fine-needle aspiration of the liver is usually performed with a long needle of about which gauge?
A thin 22 G (about 0.7 mm) needle, often 15 cm long, samples liver lesions with low bleeding risk; wide-bore needles are for core biopsy.
A patient has an enlarged liver with a palpable tumour mass. Which aspiration approach is usually preferred?
A palpable mass below the costal margin can be aspirated directly subcostally, targeting the tumour and avoiding the pleura.
In the Papanicolaou stain, which counterstain is polychrome and colours cytoplasm green or pink?
EA contains eosin and light green, giving differential cytoplasmic colours; OG-6 is a single orange dye for keratin.
Which is a recognised limitation of fine-needle aspiration compared with core or excision biopsy?
FNA yields dispersed cells, so architecture and invasion are not assessable; it is quick, cheap, repeatable and needs no general anaesthesia.
Which tumour feature most often causes a false-negative FNA due to a poor cell yield?
Fibrotic tumours hold cells tightly, so aspirates are scant; highly cellular soft tumours aspirate easily. Necrosis can also cause misses.
A key limitation of breast ultrasound in diagnosing masses is that:
Ultrasound readily separates cysts from solid lesions and guides needles, but many solid lesions look similar, so cytology or biopsy is required.