[카테고리:] Clinical cases

Why I Measure Twice: The Importance of Precision in Ultrasound

In ultrasound, a few millimeters can change everything.

A measurement of 9.8 mm and 10.2 mm may look nearly identical on the screen.

But in clinical context, that small difference can shift counseling, follow-up plans, and parental anxiety.

Over the years, I have learned one thing clearly:

I measure twice.

When a Borderline Number Changes the Conversation

Consider mild ventriculomegaly.

At 9.8 mm, the ventricle is technically within normal range.

At 10.2 mm, it crosses into the “mild” category.

The baby has not changed in those seconds.

Only the caliper position has.

Yet that small number may change how parents hear the news.

That is why precision matters.

Fetal Position Matters More Than We Admit

An oblique plane.

A slightly compressed head.

A fetus facing downward.

Each of these can subtly alter measurements.

In borderline cases, I do not rush.

Sometimes I wait.

Sometimes I rescan.

Sometimes I ask the mother to change position.

Because clarity is worth patience.

The Weight of a Caliper

To the outside observer, placing calipers seems mechanical.

But in reality, it carries responsibility.

A few millimeters may influence:

  • Follow-up intervals
  • Additional imaging
  • Parental stress
  • Clinical decisions

Precision is not about perfection —

it is about respect for the consequences.

Slowing Down Is Not Weakness

Early in my career, I felt pressure to be fast.

Now I understand that slowing down is strength.

When a finding is borderline, I look again.

Not because I doubt myself —

but because I understand the weight of the number.

Final Thoughts

Ultrasound is not just imaging.

It is interpretation, responsibility, and communication.

Sometimes the most important part of the scan

is the decision to measure twice.

🦶 Isolated 4th Curly Toe at 22 Weeks

Normal Variant or Something to Worry About?

Case Summary

  • Gestational age: 22 weeks 3 days
  • Examination: Detailed second-trimester ultrasound
  • Finding: Flexed appearance of the right 4th toe

Ultrasound Findings

  • Flexion of the right 4th toe
  • Other toes aligned normally
  • Normal foot length and shape
  • No rocker-bottom configuration
  • No syndactyly
  • Long bones within normal range
  • No additional structural abnormalities

👉 Isolated finding

What Is a Curly Toe?

A curly toe refers to a flexed or slightly underlapping toe appearance.

In fetal ultrasound, this can be seen due to:

  • Intrauterine positioning
  • Transient muscular tone
  • Normal anatomical variation

The 4th toe, in particular, may appear flexed because of its anatomical alignment and scanning angle.

Is It a Soft Marker?

Isolated curly toe is not considered a strong soft marker for chromosomal abnormalities.

However, further evaluation is important when:

  • Multiple anomalies are present
  • Persistent overlapping toes are observed
  • Fixed deformity is suspected
  • Associated skeletal abnormalities exist

In this case, no additional abnormalities were identified.

What Should Be Checked?

When a curved toe is seen, the examiner should assess:

✔ Overall toe alignment

✔ Foot contour

✔ Long bone measurements

✔ Presence of other structural anomalies

✔ Fetal growth pattern

Context is everything.

Counseling Perspective

When isolated and not associated with other findings, a curly toe is most often:

  • Positional
  • Benign
  • Likely to resolve or remain clinically insignificant

Follow-up imaging can help confirm stability.

🔎 Clinical Takeaway

Not every unusual image represents pathology.

Ultrasound interpretation requires pattern recognition and context.

An isolated 4th curly toe at mid-gestation is usually a normal variant.

22주 정밀초음파에서 보인 4th Curly Toe — 정상 변이일까?

1️⃣ 기본 정보

  • 임신 주수: 22주 3일
  • 검사: 정밀 초음파
  • 관찰 소견: 우측 4번째 발가락 굴곡 소견

2️⃣ 초음파 소견

  • 우측 발에서 4번째 발가락이 굴곡된 모습 관찰
  • 다른 발가락 배열은 비교적 정상 정렬
  • 발 길이 및 발바닥 형태 정상
  • Long bone 길이 정상 범위
  • 명확한 overlapping toes 소견은 아님
  • 고정된 변형인지 여부는 추적 필요

👉 단독 isolated finding

3️⃣ Curly Toe란?

Curly toe는 발가락이 굴곡(flexion)되어 보이는 상태로,

태아기 초음파에서 비교적 흔하게 관찰될 수 있습니다.

대부분은:

  • 자궁 내 자세 영향
  • 일시적인 위치 변화
  • 출생 후 자연 교정

으로 이어집니다.

특히 4번째 발가락은

구조적으로 굴곡이 잘 보일 수 있는 위치입니다.

4️⃣ 우리가 반드시 확인해야 할 것

발가락 굴곡이 보일 때는 다음을 함께 평가합니다:

✔ 다른 발가락 정렬

✔ 발바닥 아치 형태

✔ Rocker-bottom foot 여부

✔ Syndactyly 여부

✔ 장골 길이

✔ 다른 구조적 이상 동반 여부

이 케이스에서는

동반 기형은 관찰되지 않았습니다.

5️⃣ Soft Marker일까?

일반적으로 isolated curly toe는

염색체 이상과의 직접적인 연관성은 낮습니다.

하지만

  • 여러 소견이 함께 있을 경우
  • 지속적이고 고정된 overlapping toe일 경우

→ 추가 평가가 필요합니다.

현재 케이스는 단독 소견이며

임상적으로 의미가 크지 않을 가능성이 높습니다.

6️⃣ 환자 설명 관점

“현재 보이는 발가락 굴곡은 대부분 태아 자세에 따른 일시적인 모습일 가능성이 높습니다. 다른 이상 소견은 보이지 않으며, 추적 관찰을 통해 변화 여부를 확인하겠습니다.”

7️⃣ 교육적 포인트

  • 작은 변이를 과잉 해석하지 않는다.
  • 단독 소견인지 반드시 확인한다.
  • ‘구조’와 ‘패턴’을 함께 본다.
  • follow-up의 중요성.

📌 Take Home Message

Isolated 4th curly toe는

대부분 정상 변이에 가깝습니다.

초음파는 “이상 찾기”가 아니라

“맥락을 읽는 검사”입니다.

🧠 Case Review

Small CSP + Suspected Horseshoe Kidney + Borderline Oligohydramnios at 22+5 Weeks

1️⃣ Background

  • Gestational age: 22 weeks 5 days
  • Indication: Detailed second-trimester anatomy scan
  • No known prior abnormalities

2️⃣ Key Ultrasound Findings

🧠 Central Nervous System

  • Cavum Septi Pellucidi (CSP) appears small
  • No ventriculomegaly
  • Posterior fossa structures grossly normal
  • Corpus callosum not fully assessed in mid-sagittal plane

🔎 Recommendation: Dedicated mid-sagittal view for corpus callosum evaluation

🩺 Renal Findings

  • Both kidneys appear low-lying
  • Suspicious midline fusion anterior to the aorta
  • Renal isthmus suspected on transverse view

➡ Suspicion: Horseshoe kidney

💧 Amniotic Fluid

  • AFI: 6.7 cm
  • Borderline oligohydramnios

🔎 Fetal bladder visualized

🔎 Follow-up fluid trend recommended

3️⃣ Clinical Significance

This is not a single-marker case.

The combination of:

  • Small CSP
  • Possible horseshoe kidney
  • Borderline AFI

Raises the question of:

  • Isolated incidental findings
    vs
  • Underlying midline developmental issue
    vs
  • Chromosomal or syndromic association

4️⃣ Differential Considerations

① Isolated Horseshoe Kidney

  • Often good prognosis
  • May be incidental

② Midline Developmental Spectrum

  • Small CSP may warrant corpus callosum assessment
  • Evaluate septal integrity and callosal length

③ Chromosomal Association

  • Horseshoe kidney reported in Trisomy 18
  • Consider soft markers review
  • Genetic counseling if additional findings emerge

④ Renal Function & Fluid Correlation

  • Borderline AFI may reflect:
    • Measurement variability
    • Early placental insufficiency
    • Subtle renal functional issue

Trend is more important than single measurement.

5️⃣ What Should Be Rechecked?

✔ Detailed mid-sagittal brain view

✔ Corpus callosum morphology

✔ Outflow tracts & aortic arch

✔ Renal isthmus confirmation with color Doppler

✔ Serial AFI

6️⃣ Educational Take-Home Points

  • Small CSP alone does not equal pathology.
  • Horseshoe kidney is frequently benign when isolated.
  • Borderline AFI should be interpreted in context.
  • Multisystem minor findings require structured thinking.
  • Follow-up imaging may be more valuable than immediate labeling.

7️⃣ Final Thought

Ultrasound is not about detecting abnormalities.

It is about understanding patterns.

Sometimes, the question is not

“Is this abnormal?”

But

“Is this connected?”

Small CSP + Horseshoe Kidney 의심 + 경계성 양수 감소

1️⃣ 기본 정보

  • 임신 주수: 22주 5일
  • 검사 목적: 정밀 초음파
  • 특이 병력: 없음

2️⃣ 주요 초음파 소견

📍 중추신경계 (CNS)

  • CSP (Cavum Septi Pellucidi) 크기 작게 보임
  • 측뇌실 확장은 없음
  • 후두와 구조는 명확한 이상 소견 없음

👉 Mid-sagittal view 재확인 필요

📍 신장 (Renal)

  • 양측 신장이 하방에 위치하며
    중앙부 연결 구조 의심
  • Transverse view에서 대동맥 전방에 연결 부위 관찰 의심

👉 Horseshoe kidney (융합신장) 가능성

📍 양수

  • AFI 약 6.7cm
  • 경계성 oligohydramnios

👉 Bladder filling 확인 필요

👉 양수 추적 관찰 권고

3️⃣ 핵심 고민 포인트

이 케이스는 단일 소견이 아닙니다.

✔ Small CSP

✔ Horseshoe kidney 의심

✔ Borderline AFI

→ 다장기(multi-system) 경미 이상 가능성

4️⃣ 감별 접근

① Isolated horseshoe kidney?

  • 단독 융합신장은 비교적 예후 양호

② Midline developmental issue?

  • Small CSP와 midline anomaly 연관성 여부

③ 염색체 이상 가능성?

  • Horseshoe kidney는 trisomy 18과 연관 보고 있음
  • 추가 소프트마커 여부 확인 필요

④ Renal function 문제로 인한 AFI 감소?

  • Bladder filling cycle 확인
  • Doppler 평가 고려

5️⃣ 재확인해야 할 구조

✔ Mid-sagittal brain view (corpus callosum 포함)

✔ Aortic arch

✔ Detailed cardiac outflow

✔ Renal isthmus confirmation

✔ AFI trend follow-up

6️⃣ 환자 설명 관점

“현재 보이는 소견은 즉각적인 결론보다는 추적 관찰이 중요한 단계입니다. 구조가 명확히 확인되는지, 변화가 있는지를 보는 것이 더 중요합니다.”

7️⃣ 교육적 포인트

미묘한 다장기 소견이 함께 보일 때는 구조적 사고가 필요하다.

작은 CSP는 단독일 경우 임상적 의미가 없을 수도 있다.

Horseshoe kidney는 단독이면 예후가 좋은 경우가 많다.

양수는 단일 측정보다 추세가 중요하다.

When the Four-Chamber View Looks Abnormal:

A Case of Prenatal Left Congenital Diaphragmatic Hernia (19+6 Weeks)

During a routine mid-trimester anatomy scan at 19 weeks and 6 days, an abnormal finding was first suspected in the four-chamber view of the fetal heart.

Initial Impression: Possible Cardiac Abnormality

The four-chamber view demonstrated:

  • Rightward displacement of the heart
  • Apparent cardiac compression
  • Mild mediastinal shift

At this stage, congenital heart disease (CHD) was initially considered.

However, ventricular size appeared relatively symmetric, and no obvious structural intracardiac defect was identified on the available views.

Re-Evaluation of Thoracic Anatomy

Further assessment of the thoracic cavity revealed a crucial finding:

  • A round anechoic structure within the left thorax
  • Absence of the stomach in its normal abdominal position
  • Persistent mediastinal shift

The anechoic structure was consistent with the fetal stomach, now located within the thoracic cavity.

This shifted the diagnostic consideration away from primary cardiac pathology and toward a diaphragmatic defect.

Suspicion of Left Congenital Diaphragmatic Hernia

Although the diaphragmatic defect itself was not sharply visualized on static images, the presence of the stomach in the thorax strongly supports the diagnosis of:

Left congenital diaphragmatic hernia (CDH).

On the current images, definite liver herniation (“liver up”) could not be confirmed. The thoracic contents appeared predominantly cystic, suggesting stomach herniation as the primary component.

Clinical Insight

This case illustrates an important diagnostic principle:

An abnormal four-chamber view does not always indicate a primary cardiac defect.

Cardiac displacement and compression may be secondary to extracardiac pathology, particularly congenital diaphragmatic hernia.

Systematic reassessment of abdominal organ position is essential whenever mediastinal shift is observed.

Recommended Next Steps

Referral to a tertiary center is advised for:

  • Detailed fetal echocardiography
  • Confirmation of the diaphragmatic defect
  • Assessment of lung development
  • Multidisciplinary counseling
Great Vessel Measurements within Expected Range
Transverse view demonstrating the main pulmonary artery (MPA) and ascending aorta(AO).
Measured diameters appear within expected range for gestational age, with no obvious discrepancy in vessel size.
Color Doppler View Demonstrating Mediastinal Shift
Color Doppler view of the upper mediastinum showing displacement of the great vessels secondary to intrathoracic herniation.
The stomach is visualized within the thoracic cavity, contributing to cardiac compression and rightward mediastinal shift.
Cardiac Displacement by Intrathoracic Stomach
Sagittal/ oblique thoracic view demonstrating the fetal heart displaced by an intrathoracic stomach.
The abnormal position of the stomach within the chest results in mediastinal shift and secondary cardiac compression, cosistent with suspected left congenital diaphragmatic hernia(CHD).
four- chamber view
4ch view at 19+6wks demonstrating right ward displacement of the heart with mild mediastinal shift.
No obvious intracardiac structural defect is identified on this image.
Outflow Tract Assessment in Suspected Cardiac Abnormality
Despite initial concern for CD based on mediastinal shift, LVOT and RVOT appear identifiable, suggesting that cardiac displacement is likely secondary rather than due to primary structure heart disease.
Great Vessel Measurements within Expected Range
Transverse view demonstrating the main pulmonary artery (MPA) and ascending aorta(AO).
Measured diameters appear within expected range for gestational age, with no obvious discrepancy in vessel size.

Fetal Ventricular Atrium Measurement at 22 Weeks | Normal Lateral Ventricle Case (5.5 mm / 6.4 mm)

🧠 Title

Fetal Ventricular Atrium Measurement at 22 Weeks | Normal Lateral Ventricle Case (5.5 mm / 6.4 mm)

📌 Meta Description

Ultrasound case of fetal lateral ventricular atrium measurement at 22+2 weeks. Both ventricles measured within normal range (Va 5.5 mm, Vp 6.4 mm). Inner-to-inner technique demonstrated.

Introduction

Accurate measurement of the fetal lateral ventricular atrium is essential during the mid-trimester anatomy scan. Ventriculomegaly is typically defined when the atrial width measures ≥10 mm.

This case demonstrates normal ventricular measurements at 22+2 weeks of gestation.

Case Information

  • Gestational Age: 22+2 weeks
  • Measurement Technique: Inner-to-inner caliper placement
  • Va (Left ventricle): 5.5 mm
  • Vp (Right ventricle): 6.4 mm

Both measurements are within normal limits (<10 mm).

Ultrasound Findings

The axial plane of the fetal head was obtained at the level of the thalami.

The atrium of the lateral ventricle was measured perpendicular to the long axis of the ventricle, ensuring proper visualization of:

  • Cavum septi pellucidi
  • Thalami
  • Symmetrical hemispheres

No evidence of ventriculomegaly was observed.

Clinical Significance

Normal atrial width ranges between 5–10 mm during the second trimester.

Routine measurement is important for early detection of:

  • Mild ventriculomegaly (10–12 mm)
  • Moderate ventriculomegaly (13–15 mm)
  • Severe ventriculomegaly (>15 mm)

This case represents normal physiologic findings.

Key Learning Points

✔ Always measure inner-to-inner

✔ Obtain a true axial transventricular plane

✔ Avoid oblique measurement

✔ Confirm symmetry between both ventricles

🔎

  • fetal ventricle measurement
  • lateral ventricular atrium
  • ventriculomegaly ultrasound
  • 22 week anatomy scan
  • normal fetal ventricle size